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• 1. [Article] Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs

  This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18.

  Citation × Citation Citation Abstract Copy Title: Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs Author: Ye, T. Z., Jayawickrama, K. J. S. This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18. Title: Early Selection for Improving Volume Growth in Coastal Douglas-fir Breeding Programs Author: Ye, T. Z., Jayawickrama, K. J. S. This is the publisher’s final pdf. The published article is copyrighted by J. D. Sauerländer's Verlag and can be found at: http://www.sauerlaender-verlag.com/index.php?id=18. Close

• 2. [Article] Effect of age-based and environment-based cues on reproductive investment in Gambusia affinis

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/jo...

  Citation × Citation Citation Abstract Copy Title: Effect of age-based and environment-based cues on reproductive investment in Gambusia affinis Author: Belk, Mark C., Billman, Eric J. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758. Title: Effect of age-based and environment-based cues on reproductive investment in Gambusia affinis Author: Belk, Mark C., Billman, Eric J. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758. Close

• 3. [Article] Radiometric ages for basement rocks from the Emperor Seamounts, ODP Leg 197

  The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province ...

  Citation × Citation Citation Abstract Copy Title: Radiometric ages for basement rocks from the Emperor Seamounts, ODP Leg 197 Author: Keller, Randall A., Duncan, Robert A. The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province is based largely on radiometric ages determined several decades ago. Improvements in instrumentation, sample preparation methods, and new material obtained by recent drilling warrant a reexamination of the age relations among the older Hawaiian volcanoes. We report new age determinations (40Ar-39Ar incremental heating method) on whole rocks and feldspar separates from Detroit (Sites 1203 and 1204), Nintoku (Site 1205), and Koko (Site 1206) Seamounts (Ocean Drilling Program (ODP) Leg 197) and Meiji Seamount (Deep Sea Drilling Project (DSDP) Leg 19, Site 192). Plateaus in incremental heating age spectra for Site 1203 lava flows give a mean age of 75.8 ± 0.6 (2s) Ma, which is consistent with the normal magnetic polarity directions observed and biostratigraphic age assignments. Site 1204 lavas produced discordant spectra, indicating Ar loss by reheating and K mobilization. Six plateau ages from lava flows at Site 1205 give a mean age of 55.6 ± 0.2 Ma, corresponding to Chron 24r. Drilling at Site 1206 intersected a N-R-N magnetic polarity sequence of lava flows, from which six plateau ages give a mean age of 49.1 ± 0.2 Ma, corresponding to the Chron 21n-22r-22n sequence. Plateau ages from two feldspar separates and one lava from DSDP Site 192 range from 34 to 41 Ma, significantly younger than the Cretaceous age of overlying sediments, which we relate to postcrystallization K mobilization. Combined with new dating results from Suiko Seamount (DSDP Site 433) and volcanoes near the prominent bend in the lineament [Sharp and Clague, 2002], the overall trend is increasing volcano age from south to north along the Emperor Seamounts, consistent with the hot spot model. However, there appear to be important departures from the earlier modeled simple linear age progression, which we relate to changes in Pacific plate motion and the rate of southward motion of the Hawaiian hot spot. Title: Radiometric ages for basement rocks from the Emperor Seamounts, ODP Leg 197 Author: Keller, Randall A., Duncan, Robert A. The Hawaiian-Emperor seamount chain is the ‘‘type’’ example of an age-progressive, hot spotgenerated intraplate volcanic lineament. However, our current knowledge of the age distribution within this province is based largely on radiometric ages determined several decades ago. Improvements in instrumentation, sample preparation methods, and new material obtained by recent drilling warrant a reexamination of the age relations among the older Hawaiian volcanoes. We report new age determinations (40Ar-39Ar incremental heating method) on whole rocks and feldspar separates from Detroit (Sites 1203 and 1204), Nintoku (Site 1205), and Koko (Site 1206) Seamounts (Ocean Drilling Program (ODP) Leg 197) and Meiji Seamount (Deep Sea Drilling Project (DSDP) Leg 19, Site 192). Plateaus in incremental heating age spectra for Site 1203 lava flows give a mean age of 75.8 ± 0.6 (2s) Ma, which is consistent with the normal magnetic polarity directions observed and biostratigraphic age assignments. Site 1204 lavas produced discordant spectra, indicating Ar loss by reheating and K mobilization. Six plateau ages from lava flows at Site 1205 give a mean age of 55.6 ± 0.2 Ma, corresponding to Chron 24r. Drilling at Site 1206 intersected a N-R-N magnetic polarity sequence of lava flows, from which six plateau ages give a mean age of 49.1 ± 0.2 Ma, corresponding to the Chron 21n-22r-22n sequence. Plateau ages from two feldspar separates and one lava from DSDP Site 192 range from 34 to 41 Ma, significantly younger than the Cretaceous age of overlying sediments, which we relate to postcrystallization K mobilization. Combined with new dating results from Suiko Seamount (DSDP Site 433) and volcanoes near the prominent bend in the lineament [Sharp and Clague, 2002], the overall trend is increasing volcano age from south to north along the Emperor Seamounts, consistent with the hot spot model. However, there appear to be important departures from the earlier modeled simple linear age progression, which we relate to changes in Pacific plate motion and the rate of southward motion of the Hawaiian hot spot. Close

• 4. [Article] Use of extractable lipofuscin as an age biomarker to determine age structure of ghost shrimp (Neotrypaea californiensis) populations in west coast estuaries

  Determining age in crustaceans is inherently imprecise because they molt periodically and do not retain hard structures throughout their lifespan. Morphological measurements, such as carapace length, are ...

  Citation × Citation Citation Abstract Copy Title: Use of extractable lipofuscin as an age biomarker to determine age structure of ghost shrimp (Neotrypaea californiensis) populations in west coast estuaries Author: Cassidy, Katelyn M. Determining age in crustaceans is inherently imprecise because they molt periodically and do not retain hard structures throughout their lifespan. Morphological measurements, such as carapace length, are often used to estimate age because methods for direct ageing do not exist. However, variability in individual growth rate and molt frequency can result in a wide distribution of sizes in a single age class, making length a poor predictor of true age. Research examining the autofluorescent age pigment, lipofuscin, suggests that concentration of the pigment in neural tissues is directly related to actual age. Analysis of lipofuscin concentration has already proven to be a more effective method for determining true age in several species of crustaceans than traditional, length-based methods. The ghost shrimp, Neotrypaea californiensis, negatively impacts oyster aquaculture in Pacific Northwest estuaries. Current efforts to develop an integrated pest management plan for this species would benefit from better information on the age and growth of these animals. This study assessed the potential of using extractable lipofuscin as a method for determining age in N. californiensis. A growth study was conducted to validate the lipofuscin aging technique and develop a practical method of age determination for this species. Lipofuscin-based aging was used to determine age structures for three populations of N. californiensis and these were compared to age structures determined using traditional length-based methods. Age structures determined with analysis of lipofuscin concentration revealed several more age classes than assessments based on carapace length measurements in all sampled populations. Comparison of mean size-at- age among populations in Oregon and Washington estuaries showed growth rate varied spatially. Site-specific environmental factors like food availability, population density and tidal elevation may affect individual and population growth patterns. In this study, analysis of extractable lipofuscin proved to be a more accurate method of age determination than body-length measurements. The data presented here show that biochemical-based aging can now be widely used to assess age in N. californiensis, facilitating more in-depth investigations of basic biological and ecological processes for this species. Title: Use of extractable lipofuscin as an age biomarker to determine age structure of ghost shrimp (Neotrypaea californiensis) populations in west coast estuaries Author: Cassidy, Katelyn M. Determining age in crustaceans is inherently imprecise because they molt periodically and do not retain hard structures throughout their lifespan. Morphological measurements, such as carapace length, are often used to estimate age because methods for direct ageing do not exist. However, variability in individual growth rate and molt frequency can result in a wide distribution of sizes in a single age class, making length a poor predictor of true age. Research examining the autofluorescent age pigment, lipofuscin, suggests that concentration of the pigment in neural tissues is directly related to actual age. Analysis of lipofuscin concentration has already proven to be a more effective method for determining true age in several species of crustaceans than traditional, length-based methods. The ghost shrimp, Neotrypaea californiensis, negatively impacts oyster aquaculture in Pacific Northwest estuaries. Current efforts to develop an integrated pest management plan for this species would benefit from better information on the age and growth of these animals. This study assessed the potential of using extractable lipofuscin as a method for determining age in N. californiensis. A growth study was conducted to validate the lipofuscin aging technique and develop a practical method of age determination for this species. Lipofuscin-based aging was used to determine age structures for three populations of N. californiensis and these were compared to age structures determined using traditional length-based methods. Age structures determined with analysis of lipofuscin concentration revealed several more age classes than assessments based on carapace length measurements in all sampled populations. Comparison of mean size-at- age among populations in Oregon and Washington estuaries showed growth rate varied spatially. Site-specific environmental factors like food availability, population density and tidal elevation may affect individual and population growth patterns. In this study, analysis of extractable lipofuscin proved to be a more accurate method of age determination than body-length measurements. The data presented here show that biochemical-based aging can now be widely used to assess age in N. californiensis, facilitating more in-depth investigations of basic biological and ecological processes for this species. Close

• 5. [Article] The effects of age and neuroticism on stress reactivity and cortisol diurnal rhythms : findings from the Normative Aging Study

  We examined the effect of daily stress, age, and emotional stability/neuroticism on stress reactivity, using cortisol diurnal rhythms. We used data from the Normative Aging Study (Spiro & Bosse, 2001). ...

  Citation × Citation Citation Abstract Copy Title: The effects of age and neuroticism on stress reactivity and cortisol diurnal rhythms : findings from the Normative Aging Study Author: Proulx, Jeffrey A. We examined the effect of daily stress, age, and emotional stability/neuroticism on stress reactivity, using cortisol diurnal rhythms. We used data from the Normative Aging Study (Spiro & Bosse, 2001). The 72 men in this study ranged from 67-93 (M =79.29, SD =4.88). Multilevel modeling showed that higher daily stress predicted flatter cortisol diurnal rhythms, B = .09, p < .001, as did age, B = .01, p < .001, while those higher in neuroticism on the emotional stability/neuroticism measure showed steeper slopes for cortisol diurnal rhythms, B = -.04, p < .001. These results indicate that age and emotional stability/neuroticism levels explain some of the variance in individual differences in stress reactivity and provide a basis for future research focused on the effects of psychosocial variables on physiological outcomes. Title: The effects of age and neuroticism on stress reactivity and cortisol diurnal rhythms : findings from the Normative Aging Study Author: Proulx, Jeffrey A. We examined the effect of daily stress, age, and emotional stability/neuroticism on stress reactivity, using cortisol diurnal rhythms. We used data from the Normative Aging Study (Spiro & Bosse, 2001). The 72 men in this study ranged from 67-93 (M =79.29, SD =4.88). Multilevel modeling showed that higher daily stress predicted flatter cortisol diurnal rhythms, B = .09, p < .001, as did age, B = .01, p < .001, while those higher in neuroticism on the emotional stability/neuroticism measure showed steeper slopes for cortisol diurnal rhythms, B = -.04, p < .001. These results indicate that age and emotional stability/neuroticism levels explain some of the variance in individual differences in stress reactivity and provide a basis for future research focused on the effects of psychosocial variables on physiological outcomes. Close

• 6. [Article] Laboratory evaluation of aging for asphalt-aggregate mixtures

  This research was conducted as part of the Strategic Highway Research Program (SHRP) A-003A contract at Oregon State University to validate the findings of SHRP contracts A-002A and A-003B with regard ...

  Citation × Citation Citation Abstract Copy Title: Laboratory evaluation of aging for asphalt-aggregate mixtures Author: Sosnovske, Dan This research was conducted as part of the Strategic Highway Research Program (SHRP) A-003A contract at Oregon State University to validate the findings of SHRP contracts A-002A and A-003B with regard to aging of asphalt-aggregate mixtures. One short-term and four long-term aging methods were used to simulate aging of asphalt-aggregate mixes in the field. Four aggregates and eight asphalts for a total of 32 different material combinations were tested using different aging methods. Results of the aging studies are compared with the A-002A and A-003B studies of asphalt binder or asphalt mixed with fine aggregate. This research concludes that aging of asphalt mixes cannot be predicted by tests on asphalt binder alone since results show that aggregates have considerable influence on aging. Title: Laboratory evaluation of aging for asphalt-aggregate mixtures Author: Sosnovske, Dan This research was conducted as part of the Strategic Highway Research Program (SHRP) A-003A contract at Oregon State University to validate the findings of SHRP contracts A-002A and A-003B with regard to aging of asphalt-aggregate mixtures. One short-term and four long-term aging methods were used to simulate aging of asphalt-aggregate mixes in the field. Four aggregates and eight asphalts for a total of 32 different material combinations were tested using different aging methods. Results of the aging studies are compared with the A-002A and A-003B studies of asphalt binder or asphalt mixed with fine aggregate. This research concludes that aging of asphalt mixes cannot be predicted by tests on asphalt binder alone since results show that aggregates have considerable influence on aging. Close

• 7. [Article] Increased inflammatory response in aged mice is associated with age-related zinc deficiency and zinc transporter dysregulation

  This is the authors' peer-reviewed accepted manuscript. Version of record is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/the-journal-of-nutritional-biochemistry/

  Citation × Citation Citation Abstract Copy Title: Increased inflammatory response in aged mice is associated with age-related zinc deficiency and zinc transporter dysregulation Author: Ho, Emily, Wong, Carmen P., Mangusson, Kathy R. This is the authors' peer-reviewed accepted manuscript. Version of record is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/the-journal-of-nutritional-biochemistry/ Title: Increased inflammatory response in aged mice is associated with age-related zinc deficiency and zinc transporter dysregulation Author: Ho, Emily, Wong, Carmen P., Mangusson, Kathy R. This is the authors' peer-reviewed accepted manuscript. Version of record is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/the-journal-of-nutritional-biochemistry/ Close

• 8. [Article] Investigation of Age-Related Incidence Patterns in Adult Cancers

  One of the most commonly diagnosed illnesses in the elderly population is cancer. Despite research to explain the consistent increase in incidence rates with age, the mechanisms are largely unknown. In ...

  Citation × Citation Citation Abstract Copy Title: Investigation of Age-Related Incidence Patterns in Adult Cancers Author: Fulton, Stephanie E. One of the most commonly diagnosed illnesses in the elderly population is cancer. Despite research to explain the consistent increase in incidence rates with age, the mechanisms are largely unknown. In order to explore the patterns in age-specific cancer incidence through visualization, tables and graphs were generated via SEER*stat of incidence statistics for each reported type of cancer, including all subtypes. More specifically, data from the Surveillance, Epidemiology, and End Results (SEER) program was used to calculate age-specific rates by sex and race/ethnicity. Patterns were compared to a general trend line of the total cancer incidence from the years 1975-2013, with a focus on incidence in the age group 85+. Results varied substantially by cancer type. We defined four patterns within the cancers: an increasing trend with increasing age; a decreasing trend in older ages, a mixed pattern (some increasing, while others decrease within the same cancer type), and a bimodal curve which included peaks in childhood/adolescence and in older age. Trends varied greatly depending on the type of cancer, the age at which the cancers were diagnosed, the sex of the individual, and the race/ethnicity of the individual. Age-specific patterns in African-American populations were particularly noteworthy and are presented separately. Title: Investigation of Age-Related Incidence Patterns in Adult Cancers Author: Fulton, Stephanie E. One of the most commonly diagnosed illnesses in the elderly population is cancer. Despite research to explain the consistent increase in incidence rates with age, the mechanisms are largely unknown. In order to explore the patterns in age-specific cancer incidence through visualization, tables and graphs were generated via SEER*stat of incidence statistics for each reported type of cancer, including all subtypes. More specifically, data from the Surveillance, Epidemiology, and End Results (SEER) program was used to calculate age-specific rates by sex and race/ethnicity. Patterns were compared to a general trend line of the total cancer incidence from the years 1975-2013, with a focus on incidence in the age group 85+. Results varied substantially by cancer type. We defined four patterns within the cancers: an increasing trend with increasing age; a decreasing trend in older ages, a mixed pattern (some increasing, while others decrease within the same cancer type), and a bimodal curve which included peaks in childhood/adolescence and in older age. Trends varied greatly depending on the type of cancer, the age at which the cancers were diagnosed, the sex of the individual, and the race/ethnicity of the individual. Age-specific patterns in African-American populations were particularly noteworthy and are presented separately. Close

• 9. [Article] Awareness of Aging in Taiwan and the United States : An Examination of Ageism among College Students using Stereotypes and Future Self-views

  Ageism in the context of global population aging could lead to increasing human and economic costs. Age stereotypes tend to be negative (Hummert, 1990) and ubiquitous (Nelson, 2002) there are a variety ...

  Citation × Citation Citation Abstract Copy Title: Awareness of Aging in Taiwan and the United States : An Examination of Ageism among College Students using Stereotypes and Future Self-views Author: Allen, Pamela M. Ageism in the context of global population aging could lead to increasing human and economic costs. Age stereotypes tend to be negative (Hummert, 1990) and ubiquitous (Nelson, 2002) there are a variety of well documented detrimental consequences of negative age stereotypes on older adults' physical, cognitive and psychological outcomes (Hummert, 2011; Levy, 2009; Hess et al., 2003). This contributes to a toxic social environment for older people. The issue is of growing importance especially in Asia, where most of today's older people reside (United Nations, 2012) and where ageism appears to be on the rise despite traditional predictions that cultural collectivism and filial piety should protect against negative stereotypes (North & Fiske, 2015). Ageism is proposed by stereotype embodiment theory (Levy, 2009) to be driven by a lifespan process by which beliefs about aging are internalized from the sociocultural context of the individual beginning in childhood. In addition, age stereotypes and self-views related to aging assimilate such that age stereotypes also become internalized into one's self-view. Together, age stereotypes and self-views are components of one's overall subjective awareness of aging (AoA), an "integral psychological process or condition of the aging self" representing one's sense of having grown older (Diehl et al., 2014, p. 2). Depending on whether AoA is positive or negative it functions to enhance or constrict developmental opportunity throughout adult development, respectively. In early adulthood, a period characterized by identity consolidation (Côté, 2009; Erikson, 1968) and a developing future time orientation (Nurmi, 1991), age stereotypes stand to be internalized into one’s future oriented self-concept. Internalization of negative age stereotypes into young adults' future self-views (of one's self in old age) matters because it could give rise to negative AoA early in adulthood and developmental trajectories constraining healthy aging later in life. The cross-cultural ageism research in Western and Eastern societies has assessed stereotypes only and there has been little attention to future self-views (Markus & Nurius, 1986), developmental influences such as experiences with older people (Hagestad & Uhlenberg, 2005), or processes such as internalization by which negative stereotypes can become self-relevant (Levy, 2009). Conversely, the extant work examining internalization of age stereotypes into future self-views as of yet offers little insight into cultural or developmental factors for the processes of internalization (e.g., Kornadt & Rothermund, 2012). Therefore in this dissertation I draw on stereotype embodiment theory (Levy, 2009) and the Awareness of Aging model (Diehl et al., 2014), to examine the positivity of age stereotypes and future self-views among young adults in the U.S. and Taiwan. Data from the Cross-Cultural Perceptions of Aging Study were used to quantitatively measure experiential variables as well as the degree of positivity of age stereotypes and future self-views among 942 American and 659 Taiwanese college students using the Taiwanese developed Older Person Scale (OPS; Lu & Kao, 2009). The dissertation adapted the OPS for first time use in English before using it to examine how cultural context, personal experiences with older adults related to age segregation, and gender impact the positivity of age stereotypes and future self-views cross-culturally. Multiple group confirmatory factor analysis established partial scalar cross-cultural measurement invariance of 15-item and 17-item versions of the scale for measuring age stereotypes and future self-views, respectively. Results showed a four factor structure of the scale reflecting the domains of 1) physical abilities and appearance, 2) psychological and cognitive abilities, 3) interpersonal relationships and social engagement, and 4) employment and financial security. Content analyses of open ended descriptors of age stereotypes and future self-views among American college students provided a check on the assumption that the OPS captures content of these constructs in the population of American college students. Due to the superior psychometric properties of the OPS for measurement of the social domain, and relevance of this domain for experiences of intergenerational contact, the primary research questions were addressed with respect to the social domain. Results of moderated mediation modeling showed that, as hypothesized (hypothesis 1), Taiwanese participants exhibited less positivity in stereotypes and self-views in the psychological and social domains but not the physical or employment domains. Contrary to the expectation, Taiwanese age stereotypes were better characterized as slightly positive or ambivalent rather than negative. As predicted by hypothesis 2, females and those reporting regular experience of contact with older adults expressed more positivity in age stereotypes and future self-views in the social domain across cultural contexts. In support of hypothesis 3, age stereotypes mediated the association of 1) cultural context, and 2) contact frequency to the positivity of future self-views in the social domain. Exploratory results indicated that the strength of indirect effects did not vary significantly across cultural contexts or gender. Based on culture- and gender-based differences in interdependence of self-construals (Cross & Madson, 1997; Markus & Nurius, 1986), I hypothesize that Taiwanese students and American women would exhibit stronger association of age stereotypes to future self-views (i.e., internalization) than American men (hypothesis 4). Taiwanese and American women were found to have among the strongest internalization, but, unexpectedly, American men exhibited equal internalization and Taiwanese men exhibited the weakest internalization. A fifth hypothesis predicting that age integration (i.e., contact with both kin and non-kin older people) moderates the association of contact frequency with age stereotypes was unable to be tested due to an unbalanced response distribution on the relevant variable. Results of this dissertation reinforce the relevance of age stereotypes for future self-views among young adults and speak to the appropriateness of tailoring ageism-focused programs, policies, trainings or educational efforts to the individual or the cultural context. Title: Awareness of Aging in Taiwan and the United States : An Examination of Ageism among College Students using Stereotypes and Future Self-views Author: Allen, Pamela M. Ageism in the context of global population aging could lead to increasing human and economic costs. Age stereotypes tend to be negative (Hummert, 1990) and ubiquitous (Nelson, 2002) there are a variety of well documented detrimental consequences of negative age stereotypes on older adults' physical, cognitive and psychological outcomes (Hummert, 2011; Levy, 2009; Hess et al., 2003). This contributes to a toxic social environment for older people. The issue is of growing importance especially in Asia, where most of today's older people reside (United Nations, 2012) and where ageism appears to be on the rise despite traditional predictions that cultural collectivism and filial piety should protect against negative stereotypes (North & Fiske, 2015). Ageism is proposed by stereotype embodiment theory (Levy, 2009) to be driven by a lifespan process by which beliefs about aging are internalized from the sociocultural context of the individual beginning in childhood. In addition, age stereotypes and self-views related to aging assimilate such that age stereotypes also become internalized into one's self-view. Together, age stereotypes and self-views are components of one's overall subjective awareness of aging (AoA), an "integral psychological process or condition of the aging self" representing one's sense of having grown older (Diehl et al., 2014, p. 2). Depending on whether AoA is positive or negative it functions to enhance or constrict developmental opportunity throughout adult development, respectively. In early adulthood, a period characterized by identity consolidation (Côté, 2009; Erikson, 1968) and a developing future time orientation (Nurmi, 1991), age stereotypes stand to be internalized into one’s future oriented self-concept. Internalization of negative age stereotypes into young adults' future self-views (of one's self in old age) matters because it could give rise to negative AoA early in adulthood and developmental trajectories constraining healthy aging later in life. The cross-cultural ageism research in Western and Eastern societies has assessed stereotypes only and there has been little attention to future self-views (Markus & Nurius, 1986), developmental influences such as experiences with older people (Hagestad & Uhlenberg, 2005), or processes such as internalization by which negative stereotypes can become self-relevant (Levy, 2009). Conversely, the extant work examining internalization of age stereotypes into future self-views as of yet offers little insight into cultural or developmental factors for the processes of internalization (e.g., Kornadt & Rothermund, 2012). Therefore in this dissertation I draw on stereotype embodiment theory (Levy, 2009) and the Awareness of Aging model (Diehl et al., 2014), to examine the positivity of age stereotypes and future self-views among young adults in the U.S. and Taiwan. Data from the Cross-Cultural Perceptions of Aging Study were used to quantitatively measure experiential variables as well as the degree of positivity of age stereotypes and future self-views among 942 American and 659 Taiwanese college students using the Taiwanese developed Older Person Scale (OPS; Lu & Kao, 2009). The dissertation adapted the OPS for first time use in English before using it to examine how cultural context, personal experiences with older adults related to age segregation, and gender impact the positivity of age stereotypes and future self-views cross-culturally. Multiple group confirmatory factor analysis established partial scalar cross-cultural measurement invariance of 15-item and 17-item versions of the scale for measuring age stereotypes and future self-views, respectively. Results showed a four factor structure of the scale reflecting the domains of 1) physical abilities and appearance, 2) psychological and cognitive abilities, 3) interpersonal relationships and social engagement, and 4) employment and financial security. Content analyses of open ended descriptors of age stereotypes and future self-views among American college students provided a check on the assumption that the OPS captures content of these constructs in the population of American college students. Due to the superior psychometric properties of the OPS for measurement of the social domain, and relevance of this domain for experiences of intergenerational contact, the primary research questions were addressed with respect to the social domain. Results of moderated mediation modeling showed that, as hypothesized (hypothesis 1), Taiwanese participants exhibited less positivity in stereotypes and self-views in the psychological and social domains but not the physical or employment domains. Contrary to the expectation, Taiwanese age stereotypes were better characterized as slightly positive or ambivalent rather than negative. As predicted by hypothesis 2, females and those reporting regular experience of contact with older adults expressed more positivity in age stereotypes and future self-views in the social domain across cultural contexts. In support of hypothesis 3, age stereotypes mediated the association of 1) cultural context, and 2) contact frequency to the positivity of future self-views in the social domain. Exploratory results indicated that the strength of indirect effects did not vary significantly across cultural contexts or gender. Based on culture- and gender-based differences in interdependence of self-construals (Cross & Madson, 1997; Markus & Nurius, 1986), I hypothesize that Taiwanese students and American women would exhibit stronger association of age stereotypes to future self-views (i.e., internalization) than American men (hypothesis 4). Taiwanese and American women were found to have among the strongest internalization, but, unexpectedly, American men exhibited equal internalization and Taiwanese men exhibited the weakest internalization. A fifth hypothesis predicting that age integration (i.e., contact with both kin and non-kin older people) moderates the association of contact frequency with age stereotypes was unable to be tested due to an unbalanced response distribution on the relevant variable. Results of this dissertation reinforce the relevance of age stereotypes for future self-views among young adults and speak to the appropriateness of tailoring ageism-focused programs, policies, trainings or educational efforts to the individual or the cultural context. Close

• 10. [Article] The influence of age stratification on motives for and outcomes of caregiving in mothers and daughters

  The importance of developmental stages as well as cohort experiences has not been considered in family caregiving literature although both caregiving daughters and care-receiving mothers represent different ...

  Citation × Citation Citation Abstract Copy Title: The influence of age stratification on motives for and outcomes of caregiving in mothers and daughters Author: Shin, Hwa-Yong The importance of developmental stages as well as cohort experiences has not been considered in family caregiving literature although both caregiving daughters and care-receiving mothers represent different age groups. The conceptual bases of the age stratification model and the life course perspective suggest that mothers in different age groups, as well as daughters in different age groups, might perceive the experience of care-receiving and caregiving differently. The current study compared caregiving motives, caregiving outcomes, and the association between caregiving motives and its outcomes between 85 middle-aged (age range 35-54) and 73 young-old (age range 55-74) daughters. Further, care-receiving mothers' perceptions of their daughters' caregiving motives, their own care-receiving outcomes, and the association between mothers' perceptions of daughters' caregiving motives and care-receiving outcomes were compared between 37 young-old (age range 55-74) and 121 old-old (age range 75 or older) mothers. The results indicated that middle-aged daughters reported lower obligatory motives than did young-old daughters while young-old mothers perceived higher discretionary motives than did old-old mothers. No significant differences were found between middle-aged and young-old daughters or between young-old and old-old mothers in their perceived costs and benefits of caregiving. No significant differences were found between middle-aged and young-old daughters or between young-old and old-old mothers, in the association of caregiving motives and outcomes. This study supported the possible shift in caregiving motives from obligation to discretion. Also, this study showed that caregiving leads to rewards as well as to costs. Title: The influence of age stratification on motives for and outcomes of caregiving in mothers and daughters Author: Shin, Hwa-Yong The importance of developmental stages as well as cohort experiences has not been considered in family caregiving literature although both caregiving daughters and care-receiving mothers represent different age groups. The conceptual bases of the age stratification model and the life course perspective suggest that mothers in different age groups, as well as daughters in different age groups, might perceive the experience of care-receiving and caregiving differently. The current study compared caregiving motives, caregiving outcomes, and the association between caregiving motives and its outcomes between 85 middle-aged (age range 35-54) and 73 young-old (age range 55-74) daughters. Further, care-receiving mothers' perceptions of their daughters' caregiving motives, their own care-receiving outcomes, and the association between mothers' perceptions of daughters' caregiving motives and care-receiving outcomes were compared between 37 young-old (age range 55-74) and 121 old-old (age range 75 or older) mothers. The results indicated that middle-aged daughters reported lower obligatory motives than did young-old daughters while young-old mothers perceived higher discretionary motives than did old-old mothers. No significant differences were found between middle-aged and young-old daughters or between young-old and old-old mothers in their perceived costs and benefits of caregiving. No significant differences were found between middle-aged and young-old daughters or between young-old and old-old mothers, in the association of caregiving motives and outcomes. This study supported the possible shift in caregiving motives from obligation to discretion. Also, this study showed that caregiving leads to rewards as well as to costs. Close

• 11. [Article] Theorizing age and gender in the pursuit of love in late life

  In this dissertation, I explore how women and men in later life experience the world of dating and the pursuit of new intimate relationships. Although the mortality gap between women and men at older ages ...

  Citation × Citation Citation Abstract Copy Title: Theorizing age and gender in the pursuit of love in late life Author: Levaro, Elizabeth Bayler In this dissertation, I explore how women and men in later life experience the world of dating and the pursuit of new intimate relationships. Although the mortality gap between women and men at older ages is narrowing, as they enter their 70s, 80s, and 90s, there are still at least two unmarried women for every unmarried man. This gender imbalance is due to women's greater longevity and cultural norms based in gender relations that underlie men's preference for younger partners at all ages--and, throughout most of their lives, women's preference for older partners. Viewing the pursuit of new intimate relationships as embedded within intersecting systems of age and gender inequality, my goal was to explore how unmarried heterosexual women and men negotiate the world of dating in late life and how they view themselves and each other as aging men and women. This research focuses on White heterosexual women and men 70 years of age and older who were actively pursuing new dating relationships through personal newspaper ads and Internet dating and matching sites. Positioning the search for new intimate partners within the intersection of age relations and gender relations, I addressed two research questions. First, I sought to understand how unmarried—widowed, divorced, or always single—heterosexual women and men age 70 and older who are actively pursuing new intimate relationships view and describe their experience of the world of late-life dating, their place in it as aging men and women, and the dating partners they encounter. Second, I examined how, as men and women in aging bodies in a culture that devalues both old age and old people, they maintain, negotiate, or construct their sense of manhood and masculinity or womanhood and femininity in the context of dating, romance, and sexual intimacy. This dissertation consists of two studies, both grounded in a constructivist/interpretive paradigm and the thematic analysis of in-depth, semistructured interviews with 24 informants (11 women and 13 men) between the ages of 70 and 92. In the first study, using an intersectional framework of age relations and gender relations, I examined how internalized negative stereotypes of aging in general and one's own aging, in particular, shape the ways in which old men and women position themselves for finding romantic partners and how they manage identity to make themselves attractive romantic partners in an ageist society. Through their personal ads, Internet profiles, posted pictures, and within the interviews themselves, I found that informants both maintained and subverted age and gender expectations. They consistently resisted a self-identity as old by invoking claims and affirmations of neither looking nor acting their chronological age. Simultaneously, they communicated admonitions to potential dating partners that they should not look or act old. Both the men and the women were seeking new romantic partners younger than themselves, with the men's mean lower age 21 years younger and the women's, 10 years younger. In the second study, also grounded in considerations of age relations and gender relations, I examined informants' orientations to sexual activity and the importance of sex in their dating lives. Findings showed that, contrary to ageist stereotypes depicting old people as asexual and earlier research findings that older adults might settle for alternate intimate activities, the majority of the women and men in this study expressed interest in an intimate relationship that includes sex, and most interpreted this to mean penetrative intercourse. Nearly all of the men were sexually active with younger partners, with over half either using or holding samples of drugs for the treatment of erectile dysfunction (ED). A far smaller percentage of the women were currently dating or sexually active, and none had experience with partners who required the functional assistance of ED drugs. In conclusion, the informants present a picture of late-life dating in which individuals both consciously and unconsciously submit to, resist, and sometimes defy the structural constraints presented by societal ageism, age relations, and gender relations. The intersecting systems of inequality and oppression that impact these women and men as they pursue new love may seem only to privilege old men, offering them, for instance, advantage in terms of more lenience in showing their age and a broader age range in which to pursue dating partners. As a group, however, the women expressed more satisfaction with their lives and were less driven by the desire for an intimate partner, relishing the independence and autonomy their unattached status allowed them. Title: Theorizing age and gender in the pursuit of love in late life Author: Levaro, Elizabeth Bayler In this dissertation, I explore how women and men in later life experience the world of dating and the pursuit of new intimate relationships. Although the mortality gap between women and men at older ages is narrowing, as they enter their 70s, 80s, and 90s, there are still at least two unmarried women for every unmarried man. This gender imbalance is due to women's greater longevity and cultural norms based in gender relations that underlie men's preference for younger partners at all ages--and, throughout most of their lives, women's preference for older partners. Viewing the pursuit of new intimate relationships as embedded within intersecting systems of age and gender inequality, my goal was to explore how unmarried heterosexual women and men negotiate the world of dating in late life and how they view themselves and each other as aging men and women. This research focuses on White heterosexual women and men 70 years of age and older who were actively pursuing new dating relationships through personal newspaper ads and Internet dating and matching sites. Positioning the search for new intimate partners within the intersection of age relations and gender relations, I addressed two research questions. First, I sought to understand how unmarried—widowed, divorced, or always single—heterosexual women and men age 70 and older who are actively pursuing new intimate relationships view and describe their experience of the world of late-life dating, their place in it as aging men and women, and the dating partners they encounter. Second, I examined how, as men and women in aging bodies in a culture that devalues both old age and old people, they maintain, negotiate, or construct their sense of manhood and masculinity or womanhood and femininity in the context of dating, romance, and sexual intimacy. This dissertation consists of two studies, both grounded in a constructivist/interpretive paradigm and the thematic analysis of in-depth, semistructured interviews with 24 informants (11 women and 13 men) between the ages of 70 and 92. In the first study, using an intersectional framework of age relations and gender relations, I examined how internalized negative stereotypes of aging in general and one's own aging, in particular, shape the ways in which old men and women position themselves for finding romantic partners and how they manage identity to make themselves attractive romantic partners in an ageist society. Through their personal ads, Internet profiles, posted pictures, and within the interviews themselves, I found that informants both maintained and subverted age and gender expectations. They consistently resisted a self-identity as old by invoking claims and affirmations of neither looking nor acting their chronological age. Simultaneously, they communicated admonitions to potential dating partners that they should not look or act old. Both the men and the women were seeking new romantic partners younger than themselves, with the men's mean lower age 21 years younger and the women's, 10 years younger. In the second study, also grounded in considerations of age relations and gender relations, I examined informants' orientations to sexual activity and the importance of sex in their dating lives. Findings showed that, contrary to ageist stereotypes depicting old people as asexual and earlier research findings that older adults might settle for alternate intimate activities, the majority of the women and men in this study expressed interest in an intimate relationship that includes sex, and most interpreted this to mean penetrative intercourse. Nearly all of the men were sexually active with younger partners, with over half either using or holding samples of drugs for the treatment of erectile dysfunction (ED). A far smaller percentage of the women were currently dating or sexually active, and none had experience with partners who required the functional assistance of ED drugs. In conclusion, the informants present a picture of late-life dating in which individuals both consciously and unconsciously submit to, resist, and sometimes defy the structural constraints presented by societal ageism, age relations, and gender relations. The intersecting systems of inequality and oppression that impact these women and men as they pursue new love may seem only to privilege old men, offering them, for instance, advantage in terms of more lenience in showing their age and a broader age range in which to pursue dating partners. As a group, however, the women expressed more satisfaction with their lives and were less driven by the desire for an intimate partner, relishing the independence and autonomy their unattached status allowed them. Close

• 12. [Article] The effects of enhanced expression of the GluN2B (NR2B) subunit of the N-methyl-D-aspartate (NMDA) receptor on memory in aged animals

  As the aging population continues to grow worldwide, age-related complications are becoming more apparent within the aging population. One of the first age-related complications to become apparent is age-associated ...

  Citation × Citation Citation Abstract Copy Title: The effects of enhanced expression of the GluN2B (NR2B) subunit of the N-methyl-D-aspartate (NMDA) receptor on memory in aged animals Author: Brim, Brenna L. As the aging population continues to grow worldwide, age-related complications are becoming more apparent within the aging population. One of the first age-related complications to become apparent is age-associated memory impairment and it can make the elderly more dependent on caregivers early on. The N-methyl-D-aspartate (NMDA) receptor is important to learning and memory and appears to be especially vulnerable to the process of aging. The density of NMDA receptors declines with age more than any other ionotropic glutamate receptor. Both the density of NMDA receptors and the mRNA and protein expression of its subunits decline with age. In particular, the GluN2B subunit of the NMDA receptor shows the greatest age-related declines in expression across multiple brain regions, including the frontal lobe (including the prefrontal and frontal cortices), caudate nucleus and hippocampus. These declines are strongly correlated to age-related declines in spatial memory. Specifically, age-related decreases in the protein expression of the GluN2B subunit within crude synaptosomes of the frontal cortex of C57BL/6 mice show a relationship to the declines in performance in a long-term spatial memory task across age groups. However, within the population of aged mice, there was a subpopulation of aged mice in which higher expression of the GluN2B subunit within the synaptic membrane of the hippocampus was associated with poorer performance in the same task. Moreover, transgenic mice designed to express higher levels of the GluN2B subunit from birth also possess superior memory, including spatial memory, across adulthood to middle-age. Taken together, these data led to the hypothesis that increasing the expression of the GluN2B subunit within the aged brain could potentially alleviate age-related declines in memory. However, increasing its expression regionally was first examined since higher expression of the GluN2B subunit within the hippocampus has been associated with poorer memory in aged animals. Since age-related decreases in the protein expression of the GluN2B subunit within the frontal cortex show a relationship to impaired memory function, the first study was designed to determine if increasing GluN2B subunit expression in the frontal lobe would improve memory in aged mice. Mice received bilateral injections of either an adenoviral vector, containing cDNA specific for the GluN2B subunit and enhanced Green Fluorescent Protein (eGFP) (GluN2B vector); an adenoviral vector containing only the cDNA for eGFP (control vector); or vehicle into their frontal lobe. Spatial memory, cognitive flexibility and associative memory were assessed using the Morris water maze. Aged mice, with increased GluN2B subunit expression in the frontal lobe, exhibited improved long-term spatial memory, comparable to young mice, in the second day of training. Moreover, a higher concentration of the specific GluN2B antagonist, Ro 25-6981, was required to impair long-term spatial memory in aged mice with enhanced GluN2B subunit expression, as compared to aged controls. The requirement for greater antagonism in aged mice to block memory performance suggests that the number of GluN2B-containing receptors in their frontal lobe was enhanced and contributed to the improved memory. This study provides suggestive evidence that therapies that enhance GluN2B subunit expression within the aged brain could have the potential to ameliorate age-related memory loss. Since higher expression of the GluN2B subunit within the hippocampus of aged mice is associated with poorer memory, the second study was designed to determine if increasing GluN2B subunit expression in the hippocampus would improve or further impair memory in aged mice. This would help to determine if a therapy aimed at enhancing the GluN2B subunit expression or function of GluN2B-containing receptors throughout the aged brain could help ameliorate age-associated memory loss. Mice were injected bilaterally with either the GluN2B vector, a control vector or vehicle into the hippocampus. Spatial memory, cognitive flexibility and associative memory were assessed using the Morris water maze. Aged mice, with increased GluN2B subunit expression in the hippocampus, exhibited improved long-term spatial memory, comparable to young mice, early in training. However, there was a trend for impaired memory later in the long-term spatial memory trials. Still, these data suggest that enhancing GluN2B subunit expression in the aged hippocampus could be more beneficial to memory than harmful. In addition, the results of this study suggest that enhancing GluN2B subunit expression in different brain regions may improve memory at different phases of learning. Therefore, therapies that enhance GluN2B subunit expression throughout the aged brain could help ameliorate age-related memory loss. The first two studies demonstrated that enhancing the expression of the GluN2B subunit within either the frontal lobe or hippocampus of the aged brain has the potential to reduce age-related memory declines. However, the increase was not global nor specific to the synapse. Therefore, a third study was developed with the intent of garnering a more global increase in GluN2B subunit expression that was localized to the synapse. Cyclin dependent kinase 5 (Cdk5) enhances endocytosis of the GluN2B subunit-containing NMDA receptors from the synapse. Previous research has shown that inhibiting Cdk5 increases the number of GluN2B subunits at the synapse and within the whole cell and improves memory in young mice. This study was designed to determine if using antisense phosphorodiamidate morpholino oligomers (Morpholinos) to decrease the expression of Cdk5 protein within the brain would improve memory in aged mice. Morpholinos were conjugated to a cell penetrating peptide, which enhances cellular uptake, and delivered bilaterally to the lateral ventricles of both young and aged mice via acute stereotaxic injection. Treatments consisted of equivalent volumes and concentrations of either vehicle, control Morpholino or a Morpholino targeting the mRNA of Cdk5 (Cdk5 Morpholino). Memory was evaluated in the Morris water maze and using a novel object recognition task. Aged mice treated with the Cdk5 Morpholino exhibited improved early acquisition and spatial bias in the long-term spatial memory trials, as well as improved performance overall, compared to control Morpholino-treated aged animals. However, aged mice treated with the Cdk5 Morpholino performed similarly to vehicle-treated aged animals. The presence of the peptide-conjugated Morpholinos within the brain may have worsened performance in the Morris water maze task since control Morpholino-treated animals performed significantly worse than vehicle-treated animals. In concurrence, there was significantly greater gliosis in peptide-conjugated Morpholino-treated animals over vehicle-treated brains, suggesting it was neurotoxic. In contrast, young mice treated with the Cdk5 Morpholino showed impaired early acquisition and spatial bias but a trend for improved later learning in the long-term spatial memory task compared to control Morpholino-treated animals. Treatment with the Cdk5 Morpholino had no significant effect on cognitive flexibility, associative memory or novel object recognition for young or aged animals. Immunohistochemistry revealed increased GluN2B subunit expression within cells with characteristics of neurons and astroglia in regions of the frontal lobe, caudate nucleus and hippocampus of aged mice who received the Cdk5 Morpholino compared to control treatments. However, the increased GluN2B subunit expression appeared to be greater within the hippocampus. These results suggest that inhibiting the translation of Cdk5 using Morpholinos increased GluN2B subunit expression in both young and aged mice and may have contributed to the improved long-term spatial memory observed in aged mice, despite the Morpholino being administered at a presumably toxic concentration. An additional group of mice was used to determine a non-neurotoxic dosage of the peptide conjugated Morpholino. However, future studies are needed to determine the efficacy of the Cdk5 Morpholino at this dosage. Taken together, the studies presented here suggest that increasing expression of the GluN2B subunit within the aged brain does improve age-associated memory declines. In addition, cell penetrating peptide- conjugated Morpholinos show promise as tools for genetic manipulation within the brain and Cdk5 could prove to be a novel target for enhancing GluN2B subunit expression within the aged brain. Though future studies are needed, the studies presented here do suggest that therapies that enhance GluN2B subunit expression within the aged brain have the potential to help ameliorate memory loss. However, since enhanced GluN2B subunit expression itself can increase the potential for excitotoxicity, an optimal dose of such a therapeutic would need to be determined. Title: The effects of enhanced expression of the GluN2B (NR2B) subunit of the N-methyl-D-aspartate (NMDA) receptor on memory in aged animals Author: Brim, Brenna L. As the aging population continues to grow worldwide, age-related complications are becoming more apparent within the aging population. One of the first age-related complications to become apparent is age-associated memory impairment and it can make the elderly more dependent on caregivers early on. The N-methyl-D-aspartate (NMDA) receptor is important to learning and memory and appears to be especially vulnerable to the process of aging. The density of NMDA receptors declines with age more than any other ionotropic glutamate receptor. Both the density of NMDA receptors and the mRNA and protein expression of its subunits decline with age. In particular, the GluN2B subunit of the NMDA receptor shows the greatest age-related declines in expression across multiple brain regions, including the frontal lobe (including the prefrontal and frontal cortices), caudate nucleus and hippocampus. These declines are strongly correlated to age-related declines in spatial memory. Specifically, age-related decreases in the protein expression of the GluN2B subunit within crude synaptosomes of the frontal cortex of C57BL/6 mice show a relationship to the declines in performance in a long-term spatial memory task across age groups. However, within the population of aged mice, there was a subpopulation of aged mice in which higher expression of the GluN2B subunit within the synaptic membrane of the hippocampus was associated with poorer performance in the same task. Moreover, transgenic mice designed to express higher levels of the GluN2B subunit from birth also possess superior memory, including spatial memory, across adulthood to middle-age. Taken together, these data led to the hypothesis that increasing the expression of the GluN2B subunit within the aged brain could potentially alleviate age-related declines in memory. However, increasing its expression regionally was first examined since higher expression of the GluN2B subunit within the hippocampus has been associated with poorer memory in aged animals. Since age-related decreases in the protein expression of the GluN2B subunit within the frontal cortex show a relationship to impaired memory function, the first study was designed to determine if increasing GluN2B subunit expression in the frontal lobe would improve memory in aged mice. Mice received bilateral injections of either an adenoviral vector, containing cDNA specific for the GluN2B subunit and enhanced Green Fluorescent Protein (eGFP) (GluN2B vector); an adenoviral vector containing only the cDNA for eGFP (control vector); or vehicle into their frontal lobe. Spatial memory, cognitive flexibility and associative memory were assessed using the Morris water maze. Aged mice, with increased GluN2B subunit expression in the frontal lobe, exhibited improved long-term spatial memory, comparable to young mice, in the second day of training. Moreover, a higher concentration of the specific GluN2B antagonist, Ro 25-6981, was required to impair long-term spatial memory in aged mice with enhanced GluN2B subunit expression, as compared to aged controls. The requirement for greater antagonism in aged mice to block memory performance suggests that the number of GluN2B-containing receptors in their frontal lobe was enhanced and contributed to the improved memory. This study provides suggestive evidence that therapies that enhance GluN2B subunit expression within the aged brain could have the potential to ameliorate age-related memory loss. Since higher expression of the GluN2B subunit within the hippocampus of aged mice is associated with poorer memory, the second study was designed to determine if increasing GluN2B subunit expression in the hippocampus would improve or further impair memory in aged mice. This would help to determine if a therapy aimed at enhancing the GluN2B subunit expression or function of GluN2B-containing receptors throughout the aged brain could help ameliorate age-associated memory loss. Mice were injected bilaterally with either the GluN2B vector, a control vector or vehicle into the hippocampus. Spatial memory, cognitive flexibility and associative memory were assessed using the Morris water maze. Aged mice, with increased GluN2B subunit expression in the hippocampus, exhibited improved long-term spatial memory, comparable to young mice, early in training. However, there was a trend for impaired memory later in the long-term spatial memory trials. Still, these data suggest that enhancing GluN2B subunit expression in the aged hippocampus could be more beneficial to memory than harmful. In addition, the results of this study suggest that enhancing GluN2B subunit expression in different brain regions may improve memory at different phases of learning. Therefore, therapies that enhance GluN2B subunit expression throughout the aged brain could help ameliorate age-related memory loss. The first two studies demonstrated that enhancing the expression of the GluN2B subunit within either the frontal lobe or hippocampus of the aged brain has the potential to reduce age-related memory declines. However, the increase was not global nor specific to the synapse. Therefore, a third study was developed with the intent of garnering a more global increase in GluN2B subunit expression that was localized to the synapse. Cyclin dependent kinase 5 (Cdk5) enhances endocytosis of the GluN2B subunit-containing NMDA receptors from the synapse. Previous research has shown that inhibiting Cdk5 increases the number of GluN2B subunits at the synapse and within the whole cell and improves memory in young mice. This study was designed to determine if using antisense phosphorodiamidate morpholino oligomers (Morpholinos) to decrease the expression of Cdk5 protein within the brain would improve memory in aged mice. Morpholinos were conjugated to a cell penetrating peptide, which enhances cellular uptake, and delivered bilaterally to the lateral ventricles of both young and aged mice via acute stereotaxic injection. Treatments consisted of equivalent volumes and concentrations of either vehicle, control Morpholino or a Morpholino targeting the mRNA of Cdk5 (Cdk5 Morpholino). Memory was evaluated in the Morris water maze and using a novel object recognition task. Aged mice treated with the Cdk5 Morpholino exhibited improved early acquisition and spatial bias in the long-term spatial memory trials, as well as improved performance overall, compared to control Morpholino-treated aged animals. However, aged mice treated with the Cdk5 Morpholino performed similarly to vehicle-treated aged animals. The presence of the peptide-conjugated Morpholinos within the brain may have worsened performance in the Morris water maze task since control Morpholino-treated animals performed significantly worse than vehicle-treated animals. In concurrence, there was significantly greater gliosis in peptide-conjugated Morpholino-treated animals over vehicle-treated brains, suggesting it was neurotoxic. In contrast, young mice treated with the Cdk5 Morpholino showed impaired early acquisition and spatial bias but a trend for improved later learning in the long-term spatial memory task compared to control Morpholino-treated animals. Treatment with the Cdk5 Morpholino had no significant effect on cognitive flexibility, associative memory or novel object recognition for young or aged animals. Immunohistochemistry revealed increased GluN2B subunit expression within cells with characteristics of neurons and astroglia in regions of the frontal lobe, caudate nucleus and hippocampus of aged mice who received the Cdk5 Morpholino compared to control treatments. However, the increased GluN2B subunit expression appeared to be greater within the hippocampus. These results suggest that inhibiting the translation of Cdk5 using Morpholinos increased GluN2B subunit expression in both young and aged mice and may have contributed to the improved long-term spatial memory observed in aged mice, despite the Morpholino being administered at a presumably toxic concentration. An additional group of mice was used to determine a non-neurotoxic dosage of the peptide conjugated Morpholino. However, future studies are needed to determine the efficacy of the Cdk5 Morpholino at this dosage. Taken together, the studies presented here suggest that increasing expression of the GluN2B subunit within the aged brain does improve age-associated memory declines. In addition, cell penetrating peptide- conjugated Morpholinos show promise as tools for genetic manipulation within the brain and Cdk5 could prove to be a novel target for enhancing GluN2B subunit expression within the aged brain. Though future studies are needed, the studies presented here do suggest that therapies that enhance GluN2B subunit expression within the aged brain have the potential to help ameliorate memory loss. However, since enhanced GluN2B subunit expression itself can increase the potential for excitotoxicity, an optimal dose of such a therapeutic would need to be determined. Close

• 13. [Article] Effect of consumers' and salespersons' age on perceptions of salespeople

  Physical appearance is one of the most important cues that an individual uses in forming an impression of another person. Researchers have found that perceptions of age are negatively related to perceptions ...

  Citation × Citation Citation Abstract Copy Title: Effect of consumers' and salespersons' age on perceptions of salespeople Author: Cho, Shi Jean Physical appearance is one of the most important cues that an individual uses in forming an impression of another person. Researchers have found that perceptions of age are negatively related to perceptions of physical attractiveness. Because salespeople are influential in affecting a store's sales, especially for nondurable goods (Undell, 1972), consumers' perceptions of salespeople may influence the store's image and sales outcomes. The purpose of the present study was to investigate consumers' perceptions of salespeople of different ages and to determine if differences in these perceptions were related to consumers' age and salespersons' age. Two groups of subjects were investigated - younger adults (between 18 and 28 years of age) and older adults (55 years of age and older) . Younger adult subjects were recruited from university classrooms (n = 41). Older adult subjects were the recipients of Oregon Horne Economics Extension Newsletter (n = 46). The total sample size was 87. A questionnaire was used in the present study to investigate a consumer's perceptions. The questionnaire included three parts questions on the respondent's shopping patterns, a consumer shopping scenario which included the salesperson's age manipulation, and questions asking demographic information. Three dependent variables were measured in the questionnaire: perceptions of the salesperson's fashionability, product knowledge, and job performance. The data were analyzed using the chi-square statistic and content analysis. Results indicated that consumers' perceptions of a salesperson's fashionability was related to the age of the salesperson. Perceptions of a salesperson's fashionability was also related to the age of consumer and the age of the salesperson. Perceptions of the salesperson's product knowledge and performance were not related to the age of salesperson nor to the age of the consumers. Title: Effect of consumers' and salespersons' age on perceptions of salespeople Author: Cho, Shi Jean Physical appearance is one of the most important cues that an individual uses in forming an impression of another person. Researchers have found that perceptions of age are negatively related to perceptions of physical attractiveness. Because salespeople are influential in affecting a store's sales, especially for nondurable goods (Undell, 1972), consumers' perceptions of salespeople may influence the store's image and sales outcomes. The purpose of the present study was to investigate consumers' perceptions of salespeople of different ages and to determine if differences in these perceptions were related to consumers' age and salespersons' age. Two groups of subjects were investigated - younger adults (between 18 and 28 years of age) and older adults (55 years of age and older) . Younger adult subjects were recruited from university classrooms (n = 41). Older adult subjects were the recipients of Oregon Horne Economics Extension Newsletter (n = 46). The total sample size was 87. A questionnaire was used in the present study to investigate a consumer's perceptions. The questionnaire included three parts questions on the respondent's shopping patterns, a consumer shopping scenario which included the salesperson's age manipulation, and questions asking demographic information. Three dependent variables were measured in the questionnaire: perceptions of the salesperson's fashionability, product knowledge, and job performance. The data were analyzed using the chi-square statistic and content analysis. Results indicated that consumers' perceptions of a salesperson's fashionability was related to the age of the salesperson. Perceptions of a salesperson's fashionability was also related to the age of consumer and the age of the salesperson. Perceptions of the salesperson's product knowledge and performance were not related to the age of salesperson nor to the age of the consumers. Close

• 14. [Article] A model of fall chinook salmon (Onchorhynchus tshawytscha) life history

  The research involved development of two ecological simulation models to explain the complex dimensionality of chinook salmon (Oncorhynchus tshawytscha) life history structure (represented by the age composition ...

  Citation × Citation Citation Abstract Copy Title: A model of fall chinook salmon (Onchorhynchus tshawytscha) life history Author: Hirai, Takayuki The research involved development of two ecological simulation models to explain the complex dimensionality of chinook salmon (Oncorhynchus tshawytscha) life history structure (represented by the age composition of the spawning stock) and management difficulties entailed in the complexity. Since different sizes of chinook salmon are thought to adapt differently to heterogeneous habitats, age composition of the spawning stock is determined by characteristics of the habitats of the substocks. Numerical properties of substocks result from the incorporation of individual spawners in different age classes and each substock performs differently because their age compositions are distinctive. A stock or population consists of substocks whose age compositions are concordant with their habitats. The productive capacity of a population will result from the incorporation of substocks. If habitat structures of streams are different, the age and size compositions and productive capacity of the populations may differ. Selective harvesting affects spawners in different ways, so that age compositions must be deformed differently by fishing pressure. Once the age composition deviates from the natural age composition, the productivity of the population will decrease. Population dynamics are strongly correlated with substock structure which is determined by habitat structure in a stream system. Hierarchical population structure make fisheries management difficult and requires not only quantitative but also qualitative analysis on the populations in relation to habitat classification. Title: A model of fall chinook salmon (Onchorhynchus tshawytscha) life history Author: Hirai, Takayuki The research involved development of two ecological simulation models to explain the complex dimensionality of chinook salmon (Oncorhynchus tshawytscha) life history structure (represented by the age composition of the spawning stock) and management difficulties entailed in the complexity. Since different sizes of chinook salmon are thought to adapt differently to heterogeneous habitats, age composition of the spawning stock is determined by characteristics of the habitats of the substocks. Numerical properties of substocks result from the incorporation of individual spawners in different age classes and each substock performs differently because their age compositions are distinctive. A stock or population consists of substocks whose age compositions are concordant with their habitats. The productive capacity of a population will result from the incorporation of substocks. If habitat structures of streams are different, the age and size compositions and productive capacity of the populations may differ. Selective harvesting affects spawners in different ways, so that age compositions must be deformed differently by fishing pressure. Once the age composition deviates from the natural age composition, the productivity of the population will decrease. Population dynamics are strongly correlated with substock structure which is determined by habitat structure in a stream system. Hierarchical population structure make fisheries management difficult and requires not only quantitative but also qualitative analysis on the populations in relation to habitat classification. Close

• 15. [Article] Correction of deposit ages for inherited ages of charcoal: implications for sediment dynamics inferred from random sampling of deposits on headwater valley floors

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.sciencedirect.com/science/journal/0277...

  Citation × Citation Citation Abstract Copy Title: Correction of deposit ages for inherited ages of charcoal: implications for sediment dynamics inferred from random sampling of deposits on headwater valley floors Author: Frueh, W. Terry, Lancaster, Stephen T. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.sciencedirect.com/science/journal/02773791. Title: Correction of deposit ages for inherited ages of charcoal: implications for sediment dynamics inferred from random sampling of deposits on headwater valley floors Author: Frueh, W. Terry, Lancaster, Stephen T. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.sciencedirect.com/science/journal/02773791. Close

• 16. [Article] Mitochondrial decay in the aging rat heart : changes in fatty acid-supported bioenergetics and macromolecular organization of the electron transport system

  Decline in cardiac pump function is a hallmark of aging where mitochondrial decay is an important underlying cause. Although certainly multifactorial in nature, both dysfunction of the machinery involved ...

  Citation × Citation Citation Abstract Copy Title: Mitochondrial decay in the aging rat heart : changes in fatty acid-supported bioenergetics and macromolecular organization of the electron transport system Author: Gomez Ramirez, Luis A. (Luis Alejandro) Decline in cardiac pump function is a hallmark of aging where mitochondrial decay is an important underlying cause. Although certainly multifactorial in nature, both dysfunction of the machinery involved in the chemiosmotic process of energy transduction and lower capacity to maintain fatty acid-driven respiration are identified as intrinsic factors of mitochondrial decay in the aged myocardium. Age-associated destabilization of electron transport supercomplexes as a potential factor of mitochondrial decay in the rat heart. Defective operation of the electron transport chain (ETC) constitutes a key mechanism involved in the age-associated loss of mitochondrial energy metabolism. Nevertheless, the molecular events underlying inefficient electron flux that ultimately leads to higher superoxide appearance and impaired respiration are not fully known. As recent biophysical evidence shows that the ETC may form large macromolecular assemblies (i.e. supercomplexes) that disintegrate in certain pathologies (e.g. heart failure or Barth syndrome) reminiscent of aging, we investigated the hypothesis that alterations in supercomplexes are partly responsible for the age-related loss of cardiac ETC function. In this dissertation, age-associated changes in supercomplex organization and stability were investigated in subsarcolemmal (SSM) and interfibrillary (IFM) mitochondria isolated from cardiac tissue from young (3-5 months) and old (24-28 months) male Fischer 344 rats. Blue native-PAGE (BN-PAGE) analysis of digitonin-solubilized mitochondrial membranes coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to investigate supercomplex organization. Results show that both SSM and IFM display supercomplexes comprised of various stoichiometries of complexes I, III and IV (never complex II), which typically organize as high mass (1500-2300 kDa) assemblies containing up to four copies of complex IV (i.e. I₁III₂IV[subscript N]-type supercomplexes). Interestingly, analysis of IFM proteins showed that, in general, supercomplex levels declined by up to 15 % (p < 0.05) with age; however, different degrees of supercomplex deterioration were observed, depending on the particular supercomplex investigated. Supercomplexes of the highest molecular weights (i.e. 1900-2300 kDa), which were also composed of the most complex stoichiometries (i.e. I1III2IVN, N ≥ 2), were primarily lost with age. In particular, I₁III₂IV₂, I₁III₂IV₃ and I₁III₂IV₄ supercomplexes were found to decline by 13% (p < 0.05), 30% (p < 0.05) and 45% (p < 0.05), respectively, on an age basis. Therefore, the age-associated loss of supercomplexes in IFM stems from destabilization of the assemblies that comprise several copies of complex IV, which could partially limit proper electron transfer to O₂ for its reduction, affecting mitochondrial respiratory capacity. In contrast to IFM, the aging defects of SSM supercomplexes appeared to be confined to the assembly comprised of only one copy of complex IV (I₁III₂IV₁, 1700 kDa) (37% loss; p = 0.06), while the higher molecular weight supercomplex sub-types that were most affected in IFM (i.e. I₁III₂IV[subscript N], N ≥ 2) were not significantly altered with age. Thus, the results from this dissertation indicate that mitochondria from different subcellular locations in the myocyte show different degrees of supercomplex destabilization in the aging rat heart. The more robust supercomplex deficits noted for IFM fit well with previous observations that electron transport characteristics of this subpopulation are more adversely affected with age than SSM. Although the underlying factor(s) of supercomplex deterioration are not fully known, the hypothesis that age-related alterations of certain constituents of the IMM (e.g. cardiolipin) may be important factors of supercomplex destabilization in cardiac mitochondria was investigated in this dissertation. To this end, LC-MS/MS characterization of supercomplex proteins and HPLC analysis of cardiolipin were used as approaches to elucidate potential factor(s) of supercomplex destabilization in the aging rat heart. Age-related alterations of cardiolipin levels and its acyl-chain content showed a strong parallel to the age-associated destabilization of supercomplexes. Specifically, cardiolipin levels declined by 10% (p < 0.05) in IFM, the mitochondrial subpopulation displaying the highest degree of supercomplex deterioration. In addition, the content of (18:2)₄-cardiolipin, the predominant species in the heart, was found to decline by 50% (p < 0.05) on average in both populations of cardiac mitochondria. Therefore, the data presented in this dissertation indicate that changes in cardiolipin may be at least one of the factors involved in supercomplex destabilization in the aging heart. Age-related decline in carnitine palmitoyltransferase I (CPT1) activity as a mitochondrial lesion that limits fatty acid catabolism in the rat heart. Loss of fatty acid utilization, another intrinsic factor of mitochondrial decay in the aged myocardium, has been associated with age-related alterations in the activity of carnitine palmitoyltransferase 1 (CPT1), the rate-controlling enzyme for overall fatty acid β-oxidation. Nevertheless, the exact molecular mechanism involved in the age-related loss of fatty acid-driven bioenergetics is not fully understood. In this dissertation, it was also investigated whether the aging lesion for fatty oxidation lies in a particular mitochondrial subpopulation or more generally results from cardiac decrements in L-carnitine levels. In order to clarify the role of each one of these factors, the effect of long-term dietary supplementation with the L-carnitine analogue, acetyl-L-carnitine (ALCAR), was also investigated. Results show that aging selectively decreases CPT1 activity in IFM by reducing enzyme catalytic efficiency for palmitoyl-CoA. IFM displayed a 28% (p < 0.05) loss of CPT1 activity, which correlated with a decline (41%, p < 0.05) in palmitoyl-CoA-driven state 3 respiration. Interestingly, SSM had preserved enzyme function and efficiently utilized palmitate. Analysis of IFM CPT1 kinetics showed both diminished V[subscript max] and K[subscript m] (60% and 49% respectively, p < 0.05) when palmitoyl-CoA was the substrate. However, no age-related changes in enzyme kinetics were evident with respect to L-carnitine. ALCAR supplementation restored CPT1 activity in heart IFM, but not apparently through remediation of L-carnitine levels. Rather, ALCAR influenced enzyme activity over time, potentially by modulating conditions in the aging heart that ultimately affect palmitoyl-CoA binding and CPT1 kinetics. In conclusion, this dissertation presents a characterization of age-associated alterations in the macromolecular organization of the IMM components that could partly explain the loss of mitochondrial oxidative capacity that affects the aging heart. In addition, the characterization of an age-related lesion of the controlling enzyme for β-oxidation is presented as another important factor that limits mitochondrial function and energy metabolism in cardiac mitochondria. Title: Mitochondrial decay in the aging rat heart : changes in fatty acid-supported bioenergetics and macromolecular organization of the electron transport system Author: Gomez Ramirez, Luis A. (Luis Alejandro) Decline in cardiac pump function is a hallmark of aging where mitochondrial decay is an important underlying cause. Although certainly multifactorial in nature, both dysfunction of the machinery involved in the chemiosmotic process of energy transduction and lower capacity to maintain fatty acid-driven respiration are identified as intrinsic factors of mitochondrial decay in the aged myocardium. Age-associated destabilization of electron transport supercomplexes as a potential factor of mitochondrial decay in the rat heart. Defective operation of the electron transport chain (ETC) constitutes a key mechanism involved in the age-associated loss of mitochondrial energy metabolism. Nevertheless, the molecular events underlying inefficient electron flux that ultimately leads to higher superoxide appearance and impaired respiration are not fully known. As recent biophysical evidence shows that the ETC may form large macromolecular assemblies (i.e. supercomplexes) that disintegrate in certain pathologies (e.g. heart failure or Barth syndrome) reminiscent of aging, we investigated the hypothesis that alterations in supercomplexes are partly responsible for the age-related loss of cardiac ETC function. In this dissertation, age-associated changes in supercomplex organization and stability were investigated in subsarcolemmal (SSM) and interfibrillary (IFM) mitochondria isolated from cardiac tissue from young (3-5 months) and old (24-28 months) male Fischer 344 rats. Blue native-PAGE (BN-PAGE) analysis of digitonin-solubilized mitochondrial membranes coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to investigate supercomplex organization. Results show that both SSM and IFM display supercomplexes comprised of various stoichiometries of complexes I, III and IV (never complex II), which typically organize as high mass (1500-2300 kDa) assemblies containing up to four copies of complex IV (i.e. I₁III₂IV[subscript N]-type supercomplexes). Interestingly, analysis of IFM proteins showed that, in general, supercomplex levels declined by up to 15 % (p < 0.05) with age; however, different degrees of supercomplex deterioration were observed, depending on the particular supercomplex investigated. Supercomplexes of the highest molecular weights (i.e. 1900-2300 kDa), which were also composed of the most complex stoichiometries (i.e. I1III2IVN, N ≥ 2), were primarily lost with age. In particular, I₁III₂IV₂, I₁III₂IV₃ and I₁III₂IV₄ supercomplexes were found to decline by 13% (p < 0.05), 30% (p < 0.05) and 45% (p < 0.05), respectively, on an age basis. Therefore, the age-associated loss of supercomplexes in IFM stems from destabilization of the assemblies that comprise several copies of complex IV, which could partially limit proper electron transfer to O₂ for its reduction, affecting mitochondrial respiratory capacity. In contrast to IFM, the aging defects of SSM supercomplexes appeared to be confined to the assembly comprised of only one copy of complex IV (I₁III₂IV₁, 1700 kDa) (37% loss; p = 0.06), while the higher molecular weight supercomplex sub-types that were most affected in IFM (i.e. I₁III₂IV[subscript N], N ≥ 2) were not significantly altered with age. Thus, the results from this dissertation indicate that mitochondria from different subcellular locations in the myocyte show different degrees of supercomplex destabilization in the aging rat heart. The more robust supercomplex deficits noted for IFM fit well with previous observations that electron transport characteristics of this subpopulation are more adversely affected with age than SSM. Although the underlying factor(s) of supercomplex deterioration are not fully known, the hypothesis that age-related alterations of certain constituents of the IMM (e.g. cardiolipin) may be important factors of supercomplex destabilization in cardiac mitochondria was investigated in this dissertation. To this end, LC-MS/MS characterization of supercomplex proteins and HPLC analysis of cardiolipin were used as approaches to elucidate potential factor(s) of supercomplex destabilization in the aging rat heart. Age-related alterations of cardiolipin levels and its acyl-chain content showed a strong parallel to the age-associated destabilization of supercomplexes. Specifically, cardiolipin levels declined by 10% (p < 0.05) in IFM, the mitochondrial subpopulation displaying the highest degree of supercomplex deterioration. In addition, the content of (18:2)₄-cardiolipin, the predominant species in the heart, was found to decline by 50% (p < 0.05) on average in both populations of cardiac mitochondria. Therefore, the data presented in this dissertation indicate that changes in cardiolipin may be at least one of the factors involved in supercomplex destabilization in the aging heart. Age-related decline in carnitine palmitoyltransferase I (CPT1) activity as a mitochondrial lesion that limits fatty acid catabolism in the rat heart. Loss of fatty acid utilization, another intrinsic factor of mitochondrial decay in the aged myocardium, has been associated with age-related alterations in the activity of carnitine palmitoyltransferase 1 (CPT1), the rate-controlling enzyme for overall fatty acid β-oxidation. Nevertheless, the exact molecular mechanism involved in the age-related loss of fatty acid-driven bioenergetics is not fully understood. In this dissertation, it was also investigated whether the aging lesion for fatty oxidation lies in a particular mitochondrial subpopulation or more generally results from cardiac decrements in L-carnitine levels. In order to clarify the role of each one of these factors, the effect of long-term dietary supplementation with the L-carnitine analogue, acetyl-L-carnitine (ALCAR), was also investigated. Results show that aging selectively decreases CPT1 activity in IFM by reducing enzyme catalytic efficiency for palmitoyl-CoA. IFM displayed a 28% (p < 0.05) loss of CPT1 activity, which correlated with a decline (41%, p < 0.05) in palmitoyl-CoA-driven state 3 respiration. Interestingly, SSM had preserved enzyme function and efficiently utilized palmitate. Analysis of IFM CPT1 kinetics showed both diminished V[subscript max] and K[subscript m] (60% and 49% respectively, p < 0.05) when palmitoyl-CoA was the substrate. However, no age-related changes in enzyme kinetics were evident with respect to L-carnitine. ALCAR supplementation restored CPT1 activity in heart IFM, but not apparently through remediation of L-carnitine levels. Rather, ALCAR influenced enzyme activity over time, potentially by modulating conditions in the aging heart that ultimately affect palmitoyl-CoA binding and CPT1 kinetics. In conclusion, this dissertation presents a characterization of age-associated alterations in the macromolecular organization of the IMM components that could partly explain the loss of mitochondrial oxidative capacity that affects the aging heart. In addition, the characterization of an age-related lesion of the controlling enzyme for β-oxidation is presented as another important factor that limits mitochondrial function and energy metabolism in cardiac mitochondria. Close

• 17. [Article] Influences of an Anti-inflammatory Drug, Ibuprofen, on Spatial Memory and NMDA Receptor Subunit Expression During Aging

  One of the first cognitive dysfunctions to arise with aging is memory loss, affecting an estimated 85% of elderly in the U.S. over the age of 80 with Age Associated Memory Impairment. A common feature ...

  Citation × Citation Citation Abstract Copy Title: Influences of an Anti-inflammatory Drug, Ibuprofen, on Spatial Memory and NMDA Receptor Subunit Expression During Aging Author: Marquez Loza, Alejandra One of the first cognitive dysfunctions to arise with aging is memory loss, affecting an estimated 85% of elderly in the U.S. over the age of 80 with Age Associated Memory Impairment. A common feature in humans and animals experiencing memory loss with aging is the decline in N-methyl-D-aspartate (NMDA) receptorbinding densities in the brain. Variability in the effects of aging on the GluN1 subunit suggests that inflammation may play a role in NMDA receptor aging. The purpose of the present study was to determine the effects of an anti-inflammatory drug, ibuprofen, on spatial long-term & short-term memory and cognitive flexibility in male C57BL/6 mice from four different age groups (5, 14, 20, and 26 months of age at the end of testing). Mice were fed either Ibuprofen (375 ppm) in NIH31 diet or NIH31 diet alone for 6 weeks prior to testing. This dose had been shown to reduce pathology in an Alzheimer’s disease mouse model. Behavioral testing using the Morris Water Maze showed a significant effect of age on acquisition of spatial reference memory, the formation of spatial memory bias in probe trials, cognitive flexibility in reversal trials, and working memory, with 20 and 26 month old mice performing significantly worse than 5 month old mice. Ibuprofen enhanced overall performance in the working memory task when data was collapsed across naïve and test trials and ages. The oldest mice receiving ibuprofen showed significantly better delayed working memory, but near significantly (p=0.08) worse spatial reference memory, as compared to age-matched controls. In situ hybridization assays showed significant decreases over all ages in the mRNA densities for the GluN2B subunit, all GluN1 splice variants, and the GluN1-1 splice forms in the frontal lobes of mice consuming ibuprofen. The GluN1-3 splice form mRNA was significantly increased across ages in the frontal lobes of the ibuprofen-treated mice. There was no effect of ibuprofen on IL-1beta expression in the brains or spleens of these mice. These findings suggest that inflammation may play a role in working memory declines in aged animals, but the reducing effects of ibuprofen across ages on several factors, without reducing age-related increases in cytokine expression suggests that ibuprofen has effects on mRNA for the NMDA receptor that are unrelated to aging or inflammation. Title: Influences of an Anti-inflammatory Drug, Ibuprofen, on Spatial Memory and NMDA Receptor Subunit Expression During Aging Author: Marquez Loza, Alejandra One of the first cognitive dysfunctions to arise with aging is memory loss, affecting an estimated 85% of elderly in the U.S. over the age of 80 with Age Associated Memory Impairment. A common feature in humans and animals experiencing memory loss with aging is the decline in N-methyl-D-aspartate (NMDA) receptorbinding densities in the brain. Variability in the effects of aging on the GluN1 subunit suggests that inflammation may play a role in NMDA receptor aging. The purpose of the present study was to determine the effects of an anti-inflammatory drug, ibuprofen, on spatial long-term & short-term memory and cognitive flexibility in male C57BL/6 mice from four different age groups (5, 14, 20, and 26 months of age at the end of testing). Mice were fed either Ibuprofen (375 ppm) in NIH31 diet or NIH31 diet alone for 6 weeks prior to testing. This dose had been shown to reduce pathology in an Alzheimer’s disease mouse model. Behavioral testing using the Morris Water Maze showed a significant effect of age on acquisition of spatial reference memory, the formation of spatial memory bias in probe trials, cognitive flexibility in reversal trials, and working memory, with 20 and 26 month old mice performing significantly worse than 5 month old mice. Ibuprofen enhanced overall performance in the working memory task when data was collapsed across naïve and test trials and ages. The oldest mice receiving ibuprofen showed significantly better delayed working memory, but near significantly (p=0.08) worse spatial reference memory, as compared to age-matched controls. In situ hybridization assays showed significant decreases over all ages in the mRNA densities for the GluN2B subunit, all GluN1 splice variants, and the GluN1-1 splice forms in the frontal lobes of mice consuming ibuprofen. The GluN1-3 splice form mRNA was significantly increased across ages in the frontal lobes of the ibuprofen-treated mice. There was no effect of ibuprofen on IL-1beta expression in the brains or spleens of these mice. These findings suggest that inflammation may play a role in working memory declines in aged animals, but the reducing effects of ibuprofen across ages on several factors, without reducing age-related increases in cytokine expression suggests that ibuprofen has effects on mRNA for the NMDA receptor that are unrelated to aging or inflammation. Close

• 18. [Article] Age at disability onset and self-reported health status

  This is the publisher’s final pdf. The published article is copyrighted by BioMed Central Ltd. and can be found at: http://www.biomedcentral.com/bmcpublichealth/.

  Citation × Citation Citation Abstract Copy Title: Age at disability onset and self-reported health status Author: Drum, Charles, Beatty, Phillip, Nosek, Margaret A., Hall, Trevor, Campbell, Vincent A., Jamoom, Eric W., Andresen, Elena M., Suzuki, Rie, Krahn, Gloria, Fujiura, Glenn, Horner-Johnson, Willi, Cardinal, Brad This is the publisher’s final pdf. The published article is copyrighted by BioMed Central Ltd. and can be found at: http://www.biomedcentral.com/bmcpublichealth/. Title: Age at disability onset and self-reported health status Author: Drum, Charles, Beatty, Phillip, Nosek, Margaret A., Hall, Trevor, Campbell, Vincent A., Jamoom, Eric W., Andresen, Elena M., Suzuki, Rie, Krahn, Gloria, Fujiura, Glenn, Horner-Johnson, Willi, Cardinal, Brad This is the publisher’s final pdf. The published article is copyrighted by BioMed Central Ltd. and can be found at: http://www.biomedcentral.com/bmcpublichealth/. Close

• 19. [Article] Persistence and age-age genetic correlations of stem defects in Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco)

  Stem defects, including sinuosity, large branches, and the occurrence of steep-angled branches (e.g., forks and ramicorns) can occur with high frequency in young plantations of Coastal Douglas-fir (Pseudotsuga ...

  Citation × Citation Citation Abstract Copy Title: Persistence and age-age genetic correlations of stem defects in Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) Author: Temel, Fatih Stem defects, including sinuosity, large branches, and the occurrence of steep-angled branches (e.g., forks and ramicorns) can occur with high frequency in young plantations of Coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco). The importance of including these stem defects as criteria in early selection depends, in great part, on their persistence over time, and the efficiency of early selection for these traits. In this study, 90 open-pollinated families of Douglas-fir growing on three test sites in the Oregon Coast Range, and originally measured in 1984 at age 12, were remeasured in 1996, at age 24 (approximate mid-rotation age for managed plantations in this region). While the majority (62%) of trees scored as having ramicoms at age 12 still had them at age 24, most forks (53%) had become ramicorns by the second measurement. Thus, there does not seem to be a need to score forks and ramicorns separately. Although branch size was highly correlated between the two measurement dates, sinuosity scores were poorly correlated. Estimated heritabilities and genetic correlations between stem defect traits, and between stem defect traits and bole diameter at breast height (DBH), were similar at the two ages. Due to low heritabilities, estimated genetic gains for DBH and individual stem defect traits were low but consistent with earlier studies. Both branch size and the number of whorls with steep-angled branches had positive genetic correlations with DBH, indicating that selection for stem size alone will indirectly increase stem defects. Thus, it may be prudent to include these traits along with DBH as selection criteria. Sinuosity was nearly uncorrelated with DBH. With the exception of sinuosity, genetic correlations between comparable traits at the two ages were very high (>0.75), and predicted correlated responses in these traits at age 24, from selection at age 12, were nearly as great as those expected if selection was delayed until age 24. Title: Persistence and age-age genetic correlations of stem defects in Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco) Author: Temel, Fatih Stem defects, including sinuosity, large branches, and the occurrence of steep-angled branches (e.g., forks and ramicorns) can occur with high frequency in young plantations of Coastal Douglas-fir (Pseudotsuga menziesii var. menziesii (Mirb.) Franco). The importance of including these stem defects as criteria in early selection depends, in great part, on their persistence over time, and the efficiency of early selection for these traits. In this study, 90 open-pollinated families of Douglas-fir growing on three test sites in the Oregon Coast Range, and originally measured in 1984 at age 12, were remeasured in 1996, at age 24 (approximate mid-rotation age for managed plantations in this region). While the majority (62%) of trees scored as having ramicoms at age 12 still had them at age 24, most forks (53%) had become ramicorns by the second measurement. Thus, there does not seem to be a need to score forks and ramicorns separately. Although branch size was highly correlated between the two measurement dates, sinuosity scores were poorly correlated. Estimated heritabilities and genetic correlations between stem defect traits, and between stem defect traits and bole diameter at breast height (DBH), were similar at the two ages. Due to low heritabilities, estimated genetic gains for DBH and individual stem defect traits were low but consistent with earlier studies. Both branch size and the number of whorls with steep-angled branches had positive genetic correlations with DBH, indicating that selection for stem size alone will indirectly increase stem defects. Thus, it may be prudent to include these traits along with DBH as selection criteria. Sinuosity was nearly uncorrelated with DBH. With the exception of sinuosity, genetic correlations between comparable traits at the two ages were very high (>0.75), and predicted correlated responses in these traits at age 24, from selection at age 12, were nearly as great as those expected if selection was delayed until age 24. Close

• 20. [Article] Age determination of corvina reina (Cynoscion albus) in the Gulf of Nicoya, based on otolith surface readings and microincrement analysis

  The corvina reina (Cynoscion albus) is an important part of the artisanal fishery in the Gulf of Nicoya, Costa Rica. Stock assessment on this sciaenid species has been restricted to the use of length-based ...

  Citation × Citation Citation Abstract Copy Title: Age determination of corvina reina (Cynoscion albus) in the Gulf of Nicoya, based on otolith surface readings and microincrement analysis Author: Mug-Villanueva, Moises The corvina reina (Cynoscion albus) is an important part of the artisanal fishery in the Gulf of Nicoya, Costa Rica. Stock assessment on this sciaenid species has been restricted to the use of length-based methods because of the lack of age data. Direct age determination methodologies for tropical species often encounter serious difficulties such as poorly defined hyaline and opaque zones and lack of adequate techniques of ageing. This thesis presents the results of an age-determination study of Cynoscion albus based on otolith surface readings and microincrement analysis. Age estimates were obtained from counts of hyaline zones from surface readings using the light microscope and from microincrement readings from cross sections of the otolith using the scanning electron microscope. Validation of age estimates from surface readings was based on a linear regression of the age estimates from surface readings on age estimates from integrated daily increment readings. Growth of the otolith was studied using linear and multivariate regression methods and the results were used to construct multivariate models for prediction of age. Consistent estimates of age and fish growth parameters were obtained from surface and microincrement analysis. This study showed that Cynoscion albus is a slow-growing fish (K = 0.121) and reaches a large size (L∞ = 127.5 cm) and therefore is likely to suffer overfishing in the Gulf of Nicoya fishery. Title: Age determination of corvina reina (Cynoscion albus) in the Gulf of Nicoya, based on otolith surface readings and microincrement analysis Author: Mug-Villanueva, Moises The corvina reina (Cynoscion albus) is an important part of the artisanal fishery in the Gulf of Nicoya, Costa Rica. Stock assessment on this sciaenid species has been restricted to the use of length-based methods because of the lack of age data. Direct age determination methodologies for tropical species often encounter serious difficulties such as poorly defined hyaline and opaque zones and lack of adequate techniques of ageing. This thesis presents the results of an age-determination study of Cynoscion albus based on otolith surface readings and microincrement analysis. Age estimates were obtained from counts of hyaline zones from surface readings using the light microscope and from microincrement readings from cross sections of the otolith using the scanning electron microscope. Validation of age estimates from surface readings was based on a linear regression of the age estimates from surface readings on age estimates from integrated daily increment readings. Growth of the otolith was studied using linear and multivariate regression methods and the results were used to construct multivariate models for prediction of age. Consistent estimates of age and fish growth parameters were obtained from surface and microincrement analysis. This study showed that Cynoscion albus is a slow-growing fish (K = 0.121) and reaches a large size (L∞ = 127.5 cm) and therefore is likely to suffer overfishing in the Gulf of Nicoya fishery. Close

• 21. [Article] The effects of different otolith ageing techniques on estimates of growth and mortality for two species of rockfishes, Sebastes pinniger and Sebastes diploproa

  The use of some age determination methods may result in the incorrect age structure of fish populations. This in turn may lead to incorporation of inappropriate data into models used for stock management. ...

  Citation × Citation Citation Abstract Copy Title: The effects of different otolith ageing techniques on estimates of growth and mortality for two species of rockfishes, Sebastes pinniger and Sebastes diploproa Author: Wilson, Christopher D. The use of some age determination methods may result in the incorrect age structure of fish populations. This in turn may lead to incorporation of inappropriate data into models used for stock management. Otoliths are commonly used for determining the age of fishes, and ages based on the whole otoliths (surface ages) are often lower than those based on otolith sections of long-lived, slow-growing fishes such as rockfishes (Sebastes spp.). Therefore, significant overestimates in growth and mortality may occur when surface ages are used for these species. This study provides estimates of growth and total instantaneous mortality for Sebastes diploproa and S. pinniger based on ages determined from the otolith surface versus those determined from otolith sections. For both species, estimates of mortality were reduced by more than half when section rather than surface ages were used. Estimates of growth based on surface rather than section ages were nearly identical for S. diploproa but appeared higher for S. pinniger. The inclusion of posterior otolith projections in the surface counts of S. diploproa and not S. pinniger are suspected of producing these differences. Because of these revised estimates of mortality and growth the life history features and response to exploitation of these species must be re-evaluated. Maximum sustainable yields of S. ninniger and S. diploproa based on surface ages are 2 to 5 times greater for either species than yields based on section ages. Mistaken estimates such as these can lead to management errors resulting in overexploitation and may thus explain the depletion of some stocks of Sebastes spp.. Title: The effects of different otolith ageing techniques on estimates of growth and mortality for two species of rockfishes, Sebastes pinniger and Sebastes diploproa Author: Wilson, Christopher D. The use of some age determination methods may result in the incorrect age structure of fish populations. This in turn may lead to incorporation of inappropriate data into models used for stock management. Otoliths are commonly used for determining the age of fishes, and ages based on the whole otoliths (surface ages) are often lower than those based on otolith sections of long-lived, slow-growing fishes such as rockfishes (Sebastes spp.). Therefore, significant overestimates in growth and mortality may occur when surface ages are used for these species. This study provides estimates of growth and total instantaneous mortality for Sebastes diploproa and S. pinniger based on ages determined from the otolith surface versus those determined from otolith sections. For both species, estimates of mortality were reduced by more than half when section rather than surface ages were used. Estimates of growth based on surface rather than section ages were nearly identical for S. diploproa but appeared higher for S. pinniger. The inclusion of posterior otolith projections in the surface counts of S. diploproa and not S. pinniger are suspected of producing these differences. Because of these revised estimates of mortality and growth the life history features and response to exploitation of these species must be re-evaluated. Maximum sustainable yields of S. ninniger and S. diploproa based on surface ages are 2 to 5 times greater for either species than yields based on section ages. Mistaken estimates such as these can lead to management errors resulting in overexploitation and may thus explain the depletion of some stocks of Sebastes spp.. Close

• 22. [Article] Exploring functional links between circadian clocks, neurodegeneration, and aging in Drosophila melanogaster

  Circadian clocks are endogenous molecular mechanisms that coordinate daily rhythms in gene expression, cellular activities, and physiological functions with external day/night cycles. Breakdown of circadian ...

  Citation × Citation Citation Abstract Copy Title: Exploring functional links between circadian clocks, neurodegeneration, and aging in Drosophila melanogaster Author: Rakshit, Kuntol Circadian clocks are endogenous molecular mechanisms that coordinate daily rhythms in gene expression, cellular activities, and physiological functions with external day/night cycles. Breakdown of circadian rhythms such as sleep/wake cycles is associated with the onset of several neurological diseases; however, it is not clear whether disruption of rhythms is a symptom or cause of neurodegeneration, or both. To address this important question, circadian rhythms were disrupted by both genetic and environmental manipulations in Drosophila mutants prone to neurodegeneration. This led to shortening of lifespan, premature accumulation of oxidative and nervous damage during aging, and overall decline in healthspan, suggesting that circadian clocks may be causally involved in neuroprotective pathways in aging Drosophila. Recent evidence suggests bidirectional relationships between circadian rhythms and aging. While disruption of the clock mechanism accelerates aging and age-related pathologies in mammals, output rhythms of sleep and hormonal fluctuations tend to deteriorate during aging in humans, rodents, and fruit flies. To understand whether this decay is caused by defects in the core transcriptional clock, or weakening of the clock output pathways, a comprehensive study on age-related changes in the behavioral and molecular circadian rhythms was conducted using the fruit fly as a model organism. Aging caused disruption of rest/activity patterns and lengthening of the free-running period of the circadian locomotor activity rhythm. Transcriptional oscillations of four genes involved in the clock mechanism, period, timeless, Par domain protein 1ε, and vrille, were significantly reduced in heads, but not in bodies of aging flies. It was further determined that reduced transcription of these genes is not caused by the deficient expression of their activators, encoded by Clock and cycle genes. Moreover, transcriptional activation by CLOCK-CYCLE complexes is impaired despite reduced levels of the PERIOD repressor protein in old flies. These data suggest that aging alters the properties of the core transcriptional clock in flies such that both the positive and the negative limbs of the clock are attenuated. In fruit flies, the protein CRYPTOCHROME (CRY) acts in a cell-autonomous manner to synchronize circadian oscillations with light-dark cycles. The oscillatory amplitude of CRY is significantly dampened in heads of old flies at both mRNA and protein levels. Rescue of CRY using the binary GAL4/UAS system in old flies significantly enhanced the dampened molecular oscillations of several clock genes, and also strengthened the locomotor activity rhythms. There was a remarkable extension of healthspan in flies with elevated CRY. Conversely, CRY deficient mutants accumulated greater oxidative damage and showed accelerated functional decline. Interestingly, rescue of CRY in central clock neurons alone was not sufficient to restore rest/activity rhythms or extend healthspan. These data suggest novel anti-aging functions of CRY and indicate that peripheral clocks play an active role in delaying behavioral and physiological aging. Taken together, research conducted for this dissertation is a first attempt to elucidate functional links between circadian clocks, neurodegeneration, and aging. While previous evidence linking these processes was of correlative nature, functional studies conducted in this dissertation demonstrate that disruption of circadian clocks causes neurodegeneration and aging. While aging disrupts circadian rhythms at the molecular and behavioral levels, restoration of these rhythms can delay aging and improve healthspan in Drosophila. Owing to the conserved nature of clocks, novel insights obtained from this research can illuminate future translational research aimed to extend human healthspan. Title: Exploring functional links between circadian clocks, neurodegeneration, and aging in Drosophila melanogaster Author: Rakshit, Kuntol Circadian clocks are endogenous molecular mechanisms that coordinate daily rhythms in gene expression, cellular activities, and physiological functions with external day/night cycles. Breakdown of circadian rhythms such as sleep/wake cycles is associated with the onset of several neurological diseases; however, it is not clear whether disruption of rhythms is a symptom or cause of neurodegeneration, or both. To address this important question, circadian rhythms were disrupted by both genetic and environmental manipulations in Drosophila mutants prone to neurodegeneration. This led to shortening of lifespan, premature accumulation of oxidative and nervous damage during aging, and overall decline in healthspan, suggesting that circadian clocks may be causally involved in neuroprotective pathways in aging Drosophila. Recent evidence suggests bidirectional relationships between circadian rhythms and aging. While disruption of the clock mechanism accelerates aging and age-related pathologies in mammals, output rhythms of sleep and hormonal fluctuations tend to deteriorate during aging in humans, rodents, and fruit flies. To understand whether this decay is caused by defects in the core transcriptional clock, or weakening of the clock output pathways, a comprehensive study on age-related changes in the behavioral and molecular circadian rhythms was conducted using the fruit fly as a model organism. Aging caused disruption of rest/activity patterns and lengthening of the free-running period of the circadian locomotor activity rhythm. Transcriptional oscillations of four genes involved in the clock mechanism, period, timeless, Par domain protein 1ε, and vrille, were significantly reduced in heads, but not in bodies of aging flies. It was further determined that reduced transcription of these genes is not caused by the deficient expression of their activators, encoded by Clock and cycle genes. Moreover, transcriptional activation by CLOCK-CYCLE complexes is impaired despite reduced levels of the PERIOD repressor protein in old flies. These data suggest that aging alters the properties of the core transcriptional clock in flies such that both the positive and the negative limbs of the clock are attenuated. In fruit flies, the protein CRYPTOCHROME (CRY) acts in a cell-autonomous manner to synchronize circadian oscillations with light-dark cycles. The oscillatory amplitude of CRY is significantly dampened in heads of old flies at both mRNA and protein levels. Rescue of CRY using the binary GAL4/UAS system in old flies significantly enhanced the dampened molecular oscillations of several clock genes, and also strengthened the locomotor activity rhythms. There was a remarkable extension of healthspan in flies with elevated CRY. Conversely, CRY deficient mutants accumulated greater oxidative damage and showed accelerated functional decline. Interestingly, rescue of CRY in central clock neurons alone was not sufficient to restore rest/activity rhythms or extend healthspan. These data suggest novel anti-aging functions of CRY and indicate that peripheral clocks play an active role in delaying behavioral and physiological aging. Taken together, research conducted for this dissertation is a first attempt to elucidate functional links between circadian clocks, neurodegeneration, and aging. While previous evidence linking these processes was of correlative nature, functional studies conducted in this dissertation demonstrate that disruption of circadian clocks causes neurodegeneration and aging. While aging disrupts circadian rhythms at the molecular and behavioral levels, restoration of these rhythms can delay aging and improve healthspan in Drosophila. Owing to the conserved nature of clocks, novel insights obtained from this research can illuminate future translational research aimed to extend human healthspan. Close

• 23. [Article] Does temperature preference change in aging flies?

  We set out to see if a biomarker of aging in could be found in temperance preference since it was found previously to be a predictable circadian rhythm in young flies. Since flies live 70 days it can be ...

  Citation × Citation Citation Abstract Copy Title: Does temperature preference change in aging flies? Author: Giebultowicz, T., Chow, E., Chase, Teresa We set out to see if a biomarker of aging in could be found in temperance preference since it was found previously to be a predictable circadian rhythm in young flies. Since flies live 70 days it can be said that a day in the life of a fly is like a year in the life of a human. This is important because in our lab we use flies as a model organism for studying aging as to then apply to our understanding of human health and longevity. Currently most labs use over all lifespan as their biomarker of aging, but we need something that can be seen throughout the lifespan, not just at the end of it. We are always on the lookout for ways to see how aging effects the different conditions and genetic mutations we use. First we chose both wild types and genetic mutations to test for variation in results. We aged these flies at different intervals so as to have different ages to compare together. We further put these flies in alternating light-dark conditions to test together at different time points along the circadian 24 hour clock. The flies were tested in an apparatus that had a hot and cold side, with room temperature estimated in the middle along a temperature gradient that was established. There were 4 channels that separated the different groups of 50 individuals which labeled by their time of time, age, gender and genotype. After 30 minutes, a picture was taken to determine each of their temperature preference. No fly was retested and instead many bio repeats were used to establish a trend. Each fly was given a xy coordinate which a formula and computer program assigned a temperature to each. This data was averaged using statistical test and used to plot graphs of how the rhythm of temperature preference changed from young and old, and compared to the previously reported data. Title: Does temperature preference change in aging flies? Author: Giebultowicz, T., Chow, E., Chase, Teresa We set out to see if a biomarker of aging in could be found in temperance preference since it was found previously to be a predictable circadian rhythm in young flies. Since flies live 70 days it can be said that a day in the life of a fly is like a year in the life of a human. This is important because in our lab we use flies as a model organism for studying aging as to then apply to our understanding of human health and longevity. Currently most labs use over all lifespan as their biomarker of aging, but we need something that can be seen throughout the lifespan, not just at the end of it. We are always on the lookout for ways to see how aging effects the different conditions and genetic mutations we use. First we chose both wild types and genetic mutations to test for variation in results. We aged these flies at different intervals so as to have different ages to compare together. We further put these flies in alternating light-dark conditions to test together at different time points along the circadian 24 hour clock. The flies were tested in an apparatus that had a hot and cold side, with room temperature estimated in the middle along a temperature gradient that was established. There were 4 channels that separated the different groups of 50 individuals which labeled by their time of time, age, gender and genotype. After 30 minutes, a picture was taken to determine each of their temperature preference. No fly was retested and instead many bio repeats were used to establish a trend. Each fly was given a xy coordinate which a formula and computer program assigned a temperature to each. This data was averaged using statistical test and used to plot graphs of how the rhythm of temperature preference changed from young and old, and compared to the previously reported data. Close

• 24. [Article] Exploring reproductive signaling using nonconventional aquatic models: aging and reproductive function in killifish and sea anemones

  Aquatic animals possess surprising similarities to humans in reproductive signaling that are simplified or elaborated for life underwater, making them useful for studying reproductive control. In this ...

  Citation × Citation Citation Abstract Copy Title: Exploring reproductive signaling using nonconventional aquatic models: aging and reproductive function in killifish and sea anemones Author: Ferguson, Lindsey G. Aquatic animals possess surprising similarities to humans in reproductive signaling that are simplified or elaborated for life underwater, making them useful for studying reproductive control. In this thesis, killifish and sea anemones are used as models for reproductive function and aging. The aging model Nothobranchius (killifish) was used to investigate circadian rhythms and clock gene expression in reproductive tissues, and effects of the anti-aging compound resveratrol (RSV) were examined to elucidate the role of clock genes in fertility. Weak connections were found between gonadal clock gene expression and age, and RSV altered expression over time and shifted rhythmic patterns in old fish, suggesting that it may modulate circadian rhythms with age. Additionally, to understand the physiological mechanisms behind coral spawning for conservation and elucidate hormonal evolution, functions of the cnidarian leucine-rich repeat-containing G protein-coupled receptor LGRA2 were investigated in the model sea anemone Aiptasia pallida. LGRA2 was expressed near gonadal regions of sexually developed sea anemones, activated by gonadotropins, and modulated by estrogen, indicating that it is involved in regulating reproduction similarly to its mammalian homologs luteinizing hormone receptor and follicle stimulating hormone receptor. These projects together provide a One Health view of reproductive signaling and aging. Title: Exploring reproductive signaling using nonconventional aquatic models: aging and reproductive function in killifish and sea anemones Author: Ferguson, Lindsey G. Aquatic animals possess surprising similarities to humans in reproductive signaling that are simplified or elaborated for life underwater, making them useful for studying reproductive control. In this thesis, killifish and sea anemones are used as models for reproductive function and aging. The aging model Nothobranchius (killifish) was used to investigate circadian rhythms and clock gene expression in reproductive tissues, and effects of the anti-aging compound resveratrol (RSV) were examined to elucidate the role of clock genes in fertility. Weak connections were found between gonadal clock gene expression and age, and RSV altered expression over time and shifted rhythmic patterns in old fish, suggesting that it may modulate circadian rhythms with age. Additionally, to understand the physiological mechanisms behind coral spawning for conservation and elucidate hormonal evolution, functions of the cnidarian leucine-rich repeat-containing G protein-coupled receptor LGRA2 were investigated in the model sea anemone Aiptasia pallida. LGRA2 was expressed near gonadal regions of sexually developed sea anemones, activated by gonadotropins, and modulated by estrogen, indicating that it is involved in regulating reproduction similarly to its mammalian homologs luteinizing hormone receptor and follicle stimulating hormone receptor. These projects together provide a One Health view of reproductive signaling and aging. Close

• 25. [Article] The effects of population age on trade

  This paper empirically examines the effects of population aging on international trade using a cross-country panel data set for a select group of 22 OECD countries. Other recent studies have examined the ...

  Citation × Citation Citation Abstract Copy Title: The effects of population age on trade Author: Peterson, Zack T. This paper empirically examines the effects of population aging on international trade using a cross-country panel data set for a select group of 22 OECD countries. Other recent studies have examined the effects of population age on other economic variables such as growth, savings, and investment but none till now have considered age related effects on international trade. I use a simple linear empirical model to capture any age related effects on trade along with two different model specifications in this paper; one is a simple OLS and the other is a fixed effects linear trend adjusted OLS specification. The estimated results are then adjusted for heteroskedasticity and autocorrelation via the use of the Newey-West HAC estimator to account for problems common to cross-county panel data sets. I conclude that there is indeed, a positive and statistically significant (though not very robust relationship) between a country's population age and its export to GDP ratio. There are no statistically significant effects on other total trade, trade balance or import variables. Title: The effects of population age on trade Author: Peterson, Zack T. This paper empirically examines the effects of population aging on international trade using a cross-country panel data set for a select group of 22 OECD countries. Other recent studies have examined the effects of population age on other economic variables such as growth, savings, and investment but none till now have considered age related effects on international trade. I use a simple linear empirical model to capture any age related effects on trade along with two different model specifications in this paper; one is a simple OLS and the other is a fixed effects linear trend adjusted OLS specification. The estimated results are then adjusted for heteroskedasticity and autocorrelation via the use of the Newey-West HAC estimator to account for problems common to cross-county panel data sets. I conclude that there is indeed, a positive and statistically significant (though not very robust relationship) between a country's population age and its export to GDP ratio. There are no statistically significant effects on other total trade, trade balance or import variables. Close

• 26. [Article] Do Older Parents have More Self-Regulated Children?

  Strong self-regulation in early childhood is a key predictor of academic and social success from elementary school through college (McClelland et al., 2012). This study analyzed the influence of the age ...

  Citation × Citation Citation Abstract Copy Title: Do Older Parents have More Self-Regulated Children? Author: McClelland, Megan M., Harper, Kevin G. Strong self-regulation in early childhood is a key predictor of academic and social success from elementary school through college (McClelland et al., 2012). This study analyzed the influence of the age of the child’s parent on the child’s self-regulation as measured by the HTKS (Head-Toes-Knees-Shoulders) measure. Relations between children’s self-regulation scores and their parent’s age were initially examined and then were tested again after controlling for family income and child age. Higher child self-regulation was significantly related to having older parents. However, this correlation lost significance after family income (Head Start status) and child age were controlled. These results suggest that although parent age and child self-regulation are significantly related, family income and child age are stronger predictors of children’s self-regulation. Title: Do Older Parents have More Self-Regulated Children? Author: McClelland, Megan M., Harper, Kevin G. Strong self-regulation in early childhood is a key predictor of academic and social success from elementary school through college (McClelland et al., 2012). This study analyzed the influence of the age of the child’s parent on the child’s self-regulation as measured by the HTKS (Head-Toes-Knees-Shoulders) measure. Relations between children’s self-regulation scores and their parent’s age were initially examined and then were tested again after controlling for family income and child age. Higher child self-regulation was significantly related to having older parents. However, this correlation lost significance after family income (Head Start status) and child age were controlled. These results suggest that although parent age and child self-regulation are significantly related, family income and child age are stronger predictors of children’s self-regulation. Close

• 27. [Article] Time use for household tasks performed by school-age children in two-parent, two-child Oregon families

  The purpose of this study was to investigate the household tasks that school-age children perform and the average amount of time spent performing those tasks. The sample included 219 children in 135 families taken ...

  Citation × Citation Citation Abstract Copy Title: Time use for household tasks performed by school-age children in two-parent, two-child Oregon families Author: Kennedy, Louise Claudia The purpose of this study was to investigate the household tasks that school-age children perform and the average amount of time spent performing those tasks. The sample included 219 children in 135 families taken from the Oregon sample of 210 families interviewed for the Northeast Regional Research Project 113: "An Interstate Urban/Rural Comparison of Families' Time Use." Families included in this study were limited to those composed of two parents and at least one school-age child, since time data were not gathered for children under six years of age. Eighty-four families had two school-age children and 51 families had one school-age child and one younger child under six years of age. There were 116 boys and 103 girls in the 66 rural and 69 urban families. A questionnaire had been used to collect information on demographic characteristics and household data. A time chart had been used to record the precategorized activities of the homemaker, spouse, and children over six years of age for two separate 24-hour periods. The demographic variables used in the data analysis included age-group of the child, sex of the child, age of the sibling, place of residence, whether the homemaker was gainfully employed or a fulltime homemaker, occupation of homemaker, occupation of spouse, educational level of homemaker, educational level of spouse, and family income level. The chi square test of independence was used to determine whether there were relationships between the tasks school-age children performed and the demographic variables. Children's contributions to household work were concentrated in food preparation, dishwashing, shopping, housecleaning, and maintenance of home, yard, car, and pets. Fewer than 28 percent of the children contributed to care and construction of clothing and household linens, physical and nonphysical care of family members, or management. Overall, the types of tasks children performed were dependent upon the age of the child and the age of his/her sibling. Children age twelve through seventeen and those with younger siblings over six were more likely to perform household tasks than other children. Of the 219 children included in the study, 206 children (94.1 percent) contributed to household work. The number of tasks performed by a child ranged from zero to seven for one day and from zero to ten for a two-day period. One-way analysis of variance was used to test for differences in the average amount of time spent on all tasks when respondents were grouped by selected independent variables. Two null hypotheses were rejected indicating that there was a significant difference in the average amount of time spent on household tasks by school-age children according to the age-group and the sex of the child. Children ages 15 through 17 spent significantly more time performing household tasks than children in other age groups, and girls spent significantly more time performing household tasks than boys. The amount of time children contributed to household work ranged from five minutes per day to over fourteen hours per day. The average time contributed to household tasks by children was slightly over 81 minutes per day. Title: Time use for household tasks performed by school-age children in two-parent, two-child Oregon families Author: Kennedy, Louise Claudia The purpose of this study was to investigate the household tasks that school-age children perform and the average amount of time spent performing those tasks. The sample included 219 children in 135 families taken from the Oregon sample of 210 families interviewed for the Northeast Regional Research Project 113: "An Interstate Urban/Rural Comparison of Families' Time Use." Families included in this study were limited to those composed of two parents and at least one school-age child, since time data were not gathered for children under six years of age. Eighty-four families had two school-age children and 51 families had one school-age child and one younger child under six years of age. There were 116 boys and 103 girls in the 66 rural and 69 urban families. A questionnaire had been used to collect information on demographic characteristics and household data. A time chart had been used to record the precategorized activities of the homemaker, spouse, and children over six years of age for two separate 24-hour periods. The demographic variables used in the data analysis included age-group of the child, sex of the child, age of the sibling, place of residence, whether the homemaker was gainfully employed or a fulltime homemaker, occupation of homemaker, occupation of spouse, educational level of homemaker, educational level of spouse, and family income level. The chi square test of independence was used to determine whether there were relationships between the tasks school-age children performed and the demographic variables. Children's contributions to household work were concentrated in food preparation, dishwashing, shopping, housecleaning, and maintenance of home, yard, car, and pets. Fewer than 28 percent of the children contributed to care and construction of clothing and household linens, physical and nonphysical care of family members, or management. Overall, the types of tasks children performed were dependent upon the age of the child and the age of his/her sibling. Children age twelve through seventeen and those with younger siblings over six were more likely to perform household tasks than other children. Of the 219 children included in the study, 206 children (94.1 percent) contributed to household work. The number of tasks performed by a child ranged from zero to seven for one day and from zero to ten for a two-day period. One-way analysis of variance was used to test for differences in the average amount of time spent on all tasks when respondents were grouped by selected independent variables. Two null hypotheses were rejected indicating that there was a significant difference in the average amount of time spent on household tasks by school-age children according to the age-group and the sex of the child. Children ages 15 through 17 spent significantly more time performing household tasks than children in other age groups, and girls spent significantly more time performing household tasks than boys. The amount of time children contributed to household work ranged from five minutes per day to over fourteen hours per day. The average time contributed to household tasks by children was slightly over 81 minutes per day. Close

• 28. [Article] Age-specific and lifetime reproductive success of known age Northern Spotted Owls on four study areas in Oregon and Washington

  Northern Spotted Owls (Strix occidentalis caurina) are a long-lived forest owl and range-wide declines in their numbers have resulted in the species being listed as threatened under the endangered species ...

  Citation × Citation Citation Abstract Copy Title: Age-specific and lifetime reproductive success of known age Northern Spotted Owls on four study areas in Oregon and Washington Author: Loschl, Peter J. Northern Spotted Owls (Strix occidentalis caurina) are a long-lived forest owl and range-wide declines in their numbers have resulted in the species being listed as threatened under the endangered species act. While many studies have been focused on population trends and reproductive performance of Spotted Owls from different age-classes, none have examined age related performance or lifetime reproductive success of individual owls. Using data from known age Spotted Owls on four long-term demography studies in Oregon and Washington, I conducted separate analyses to examine the functional relationship of age and reproductive success, measured as the number of young fledged (NYF), and to examine lifetime reproductive success. In my age-specific analysis, I used a mixed models approach to account for repeated measures on individual owls. I found that the standard 3-level age-class approach (1-year-old, 2-year-old, adult) often used in Spotted Owl research was a poor fit relative to curvilinear and threshold models that allowed for age-dependent variation beyond age 3. A quadratic age effect was more often supported for males, whereas a threshold effect indicating a linear increase in NYF from ages 1 to 4 was most supported in the analyses of female data. Females tended to achieve a maximum in reproductive performance at earlier ages than males, and there appeared to be a negative relationship between the age when a maximum in mean NYF was reached and overall fecundity, as reported in earlier studies. Temporal variability in numbers of young fledged at each age was best modeled with a categorical year variable as opposed to a cyclic biennial ("even-odd") year effect. Lifetime reproductive success of Spotted Owls, measured as the total numbers of fledglings and recruits produced by individuals, varied widely. For owls with relatively complete data, the number of lifetime fledglings ranged from 0 to 20 and the number of lifetime offspring that were observed as recruits within study areas ranged from 0 to 7. There was a significant positive relationship between the number of lifetime young fledged and the number that later recruited locally. Seventy five percent of females and 67% of males bred at least once. Whereas 17% of females and 16% of males produced 50% of the offspring fledged by each sex, only 9% of females and 7% of males produced 50% of the banded young that were later observed as recruits. Thirty nine percent of females and 30% of males produced no fledglings and 64% of females and 69% of males produced no local recruits. Thus while most owls fledged at least 1 offspring, most did not produce any fledglings that recruited locally during the study. Cumulative proportions of individual owls that first bred at different ages indicated that females tended to initiate their breeding at earlier ages than males. Whereas 36% of females bred first at ages 1 or 2, only 19% of males bred first before age 3. Of the owls that bred, 98% of females and 91% of males bred at least once by age 6. Compared to owls on the three Oregon study areas, owls on the Cle Elum Study Area in the eastern Cascades of Washington bred early (>50% by age 2), had higher mean numbers of fledglings (>1) at most ages, and had short mean lifespans (6 years). On the Oregon study areas, owls first bred at later ages (>50% at age ≥3), had lower mean numbers of fledglings (0.4–0.7) at most ages, and had longer mean lifespans (7–9 years). These patterns appear consistent with a compensatory relationship between reproduction and survival that was suggested in at least one previous study. Life history theory is also consistent with the idea that where lower and more variable non-juvenile survival occurs (as has been documented on Cle Elum), selection pressure for earlier breeding and greater offspring production at each attempt are to be expected. Nevertheless, it is unclear if local conditions such as prey abundance, harsh winter conditions, or predation pressure act proximately to influence reproduction and survival of Spotted Owls in these studies, or if the variability in patterns of age-specific reproductive success and components of lifetime reproduction on these study areas reflect adaptive life history responses among populations of Spotted Owls. It is likely that both plasticity and life history adaptations underlie the differences and patterns that were revealed, but tests of these hypotheses were beyond the scope of my study. Title: Age-specific and lifetime reproductive success of known age Northern Spotted Owls on four study areas in Oregon and Washington Author: Loschl, Peter J. Northern Spotted Owls (Strix occidentalis caurina) are a long-lived forest owl and range-wide declines in their numbers have resulted in the species being listed as threatened under the endangered species act. While many studies have been focused on population trends and reproductive performance of Spotted Owls from different age-classes, none have examined age related performance or lifetime reproductive success of individual owls. Using data from known age Spotted Owls on four long-term demography studies in Oregon and Washington, I conducted separate analyses to examine the functional relationship of age and reproductive success, measured as the number of young fledged (NYF), and to examine lifetime reproductive success. In my age-specific analysis, I used a mixed models approach to account for repeated measures on individual owls. I found that the standard 3-level age-class approach (1-year-old, 2-year-old, adult) often used in Spotted Owl research was a poor fit relative to curvilinear and threshold models that allowed for age-dependent variation beyond age 3. A quadratic age effect was more often supported for males, whereas a threshold effect indicating a linear increase in NYF from ages 1 to 4 was most supported in the analyses of female data. Females tended to achieve a maximum in reproductive performance at earlier ages than males, and there appeared to be a negative relationship between the age when a maximum in mean NYF was reached and overall fecundity, as reported in earlier studies. Temporal variability in numbers of young fledged at each age was best modeled with a categorical year variable as opposed to a cyclic biennial ("even-odd") year effect. Lifetime reproductive success of Spotted Owls, measured as the total numbers of fledglings and recruits produced by individuals, varied widely. For owls with relatively complete data, the number of lifetime fledglings ranged from 0 to 20 and the number of lifetime offspring that were observed as recruits within study areas ranged from 0 to 7. There was a significant positive relationship between the number of lifetime young fledged and the number that later recruited locally. Seventy five percent of females and 67% of males bred at least once. Whereas 17% of females and 16% of males produced 50% of the offspring fledged by each sex, only 9% of females and 7% of males produced 50% of the banded young that were later observed as recruits. Thirty nine percent of females and 30% of males produced no fledglings and 64% of females and 69% of males produced no local recruits. Thus while most owls fledged at least 1 offspring, most did not produce any fledglings that recruited locally during the study. Cumulative proportions of individual owls that first bred at different ages indicated that females tended to initiate their breeding at earlier ages than males. Whereas 36% of females bred first at ages 1 or 2, only 19% of males bred first before age 3. Of the owls that bred, 98% of females and 91% of males bred at least once by age 6. Compared to owls on the three Oregon study areas, owls on the Cle Elum Study Area in the eastern Cascades of Washington bred early (>50% by age 2), had higher mean numbers of fledglings (>1) at most ages, and had short mean lifespans (6 years). On the Oregon study areas, owls first bred at later ages (>50% at age ≥3), had lower mean numbers of fledglings (0.4–0.7) at most ages, and had longer mean lifespans (7–9 years). These patterns appear consistent with a compensatory relationship between reproduction and survival that was suggested in at least one previous study. Life history theory is also consistent with the idea that where lower and more variable non-juvenile survival occurs (as has been documented on Cle Elum), selection pressure for earlier breeding and greater offspring production at each attempt are to be expected. Nevertheless, it is unclear if local conditions such as prey abundance, harsh winter conditions, or predation pressure act proximately to influence reproduction and survival of Spotted Owls in these studies, or if the variability in patterns of age-specific reproductive success and components of lifetime reproduction on these study areas reflect adaptive life history responses among populations of Spotted Owls. It is likely that both plasticity and life history adaptations underlie the differences and patterns that were revealed, but tests of these hypotheses were beyond the scope of my study. Close

• 29. [Article] The circadian clock gene period extends healthspan in aging Drosophila melanogaster

  There is increasing evidence that aging is affected by biological (circadian) clocks – the internal mechanisms that coordinate daily changes in gene expression, physiological functions and behavior with ...

  Citation × Citation Citation Abstract Copy Title: The circadian clock gene period extends healthspan in aging Drosophila melanogaster Author: Giebultowicz, Jadwiga M., Chow, Eileen, Rakshit, Kuntol, Kretzchmar, Doris, Krishnan, Natraj There is increasing evidence that aging is affected by biological (circadian) clocks – the internal mechanisms that coordinate daily changes in gene expression, physiological functions and behavior with external day/night cycles. Recent data suggest that disruption of the mammalian circadian clock results in accelerated aging and increased age‐related pathologies such as cancer; however, the links between loss of daily rhythms and aging are not understood. We sought to determine whether disruption of the circadian clock affects lifespan and healthspan in the model organism Drosophila melanogaster. We examined effects of a null mutation in the circadian clock gene period (per01) on the fly healthspan by challenging aging flies with short‐term oxidative stress (24h hyperoxia) and investigating their response in terms of mortality hazard, levels of oxidative damage, and functional senescence. Exposure to 24hhyperoxia during middle age significantly shortened the life expectancy in per01 but not in control flies. This homeostatic challenge also led to significantly higher accumulation of oxidative damage in per01 flies compared to controls. In addition, aging per01 flies showed accelerated functional decline, such as lower climbing ability and increased neuronal degeneration compared to age‐matched controls. Together, these data suggest that impaired stress defense pathways may contribute to accelerated aging in the per mutant. In addition, we show that the expression of per gene declines in old wild type flies, suggesting that the circadian regulatory network becomes impaired with age. Title: The circadian clock gene period extends healthspan in aging Drosophila melanogaster Author: Giebultowicz, Jadwiga M., Chow, Eileen, Rakshit, Kuntol, Kretzchmar, Doris, Krishnan, Natraj There is increasing evidence that aging is affected by biological (circadian) clocks – the internal mechanisms that coordinate daily changes in gene expression, physiological functions and behavior with external day/night cycles. Recent data suggest that disruption of the mammalian circadian clock results in accelerated aging and increased age‐related pathologies such as cancer; however, the links between loss of daily rhythms and aging are not understood. We sought to determine whether disruption of the circadian clock affects lifespan and healthspan in the model organism Drosophila melanogaster. We examined effects of a null mutation in the circadian clock gene period (per01) on the fly healthspan by challenging aging flies with short‐term oxidative stress (24h hyperoxia) and investigating their response in terms of mortality hazard, levels of oxidative damage, and functional senescence. Exposure to 24hhyperoxia during middle age significantly shortened the life expectancy in per01 but not in control flies. This homeostatic challenge also led to significantly higher accumulation of oxidative damage in per01 flies compared to controls. In addition, aging per01 flies showed accelerated functional decline, such as lower climbing ability and increased neuronal degeneration compared to age‐matched controls. Together, these data suggest that impaired stress defense pathways may contribute to accelerated aging in the per mutant. In addition, we show that the expression of per gene declines in old wild type flies, suggesting that the circadian regulatory network becomes impaired with age. Close

• 30. [Article] Development and morphology of juvenile western juniper (Juniperus occidentalis Hook.)

  Whole tree excavation of 41 western juniper (Juniperus occidentalis Hook.), ranging in age from 2 to 34 years old, was used to assess the development and structure of root systems, to determine biomass ...

  Citation × Citation Citation Abstract Copy Title: Development and morphology of juvenile western juniper (Juniperus occidentalis Hook.) Author: Kramer, Susanne Whole tree excavation of 41 western juniper (Juniperus occidentalis Hook.), ranging in age from 2 to 34 years old, was used to assess the development and structure of root systems, to determine biomass allocation patterns, and to develop mathematical relationships for estimating biomass and root system dimensions in seedling and young western juniper. Both aboveground and belowground developmental patterns, including structural components and vertical and horizontal root spread, were described relative to plant age. Tree age and height were evaluated as predictors of biomass, root length, and root system dimensions of juvenile western juniper. Seedling root systems consisted of a relatively short tap root and a few weak laterals. With advancing age, root systems expanded in depth and lateral spread. Maximum observed rooting depth and horizontal extension were 1.20 m and 5.70 m, respectively. Root biomass and length allocation shifted from tap to lateral roots with increasing plant age. Lateral root growth dominated in trees older than 10 years. The majority of lateral roots emerged from the tap root between 5 and 20 cm from the soil surface. The relative proportions of accumulated weight in shoot components changed with progressing age. Foliage biomass accounted for the largest fraction of total standing weight throughout the developmental period examined. Adult foliage was first initiated at 17 years of age. Structural tissue increased and dead biomass decreased in relative proportion as the trees grew. Western juniper root/shoot biomass ratios ranged from 0.50 to 1.75 and showed little correlation with age. Fine root/foliage ratios varied between 0.85 and 4.38, and exhibited a significant decline with age. Tree age and height were consistently strong predictors for biomass of root and shoot components, root system length, and extension. Coefficients of determination from regressions on log-log transformed data ranged from 0.70 to 0.92 for tree age and from 0.84 to 0.96 for tree height. Title: Development and morphology of juvenile western juniper (Juniperus occidentalis Hook.) Author: Kramer, Susanne Whole tree excavation of 41 western juniper (Juniperus occidentalis Hook.), ranging in age from 2 to 34 years old, was used to assess the development and structure of root systems, to determine biomass allocation patterns, and to develop mathematical relationships for estimating biomass and root system dimensions in seedling and young western juniper. Both aboveground and belowground developmental patterns, including structural components and vertical and horizontal root spread, were described relative to plant age. Tree age and height were evaluated as predictors of biomass, root length, and root system dimensions of juvenile western juniper. Seedling root systems consisted of a relatively short tap root and a few weak laterals. With advancing age, root systems expanded in depth and lateral spread. Maximum observed rooting depth and horizontal extension were 1.20 m and 5.70 m, respectively. Root biomass and length allocation shifted from tap to lateral roots with increasing plant age. Lateral root growth dominated in trees older than 10 years. The majority of lateral roots emerged from the tap root between 5 and 20 cm from the soil surface. The relative proportions of accumulated weight in shoot components changed with progressing age. Foliage biomass accounted for the largest fraction of total standing weight throughout the developmental period examined. Adult foliage was first initiated at 17 years of age. Structural tissue increased and dead biomass decreased in relative proportion as the trees grew. Western juniper root/shoot biomass ratios ranged from 0.50 to 1.75 and showed little correlation with age. Fine root/foliage ratios varied between 0.85 and 4.38, and exhibited a significant decline with age. Tree age and height were consistently strong predictors for biomass of root and shoot components, root system length, and extension. Coefficients of determination from regressions on log-log transformed data ranged from 0.70 to 0.92 for tree age and from 0.84 to 0.96 for tree height. Close

• 31. [Article] A critical examination of the ageing method for sablefish (Anoplopoma fimbria) from the U.S. west coast using edge analysis and oxytetracycline

  This thesis evaluates the current break-and-burn ageing method for the southern stock (U.S. west coast) of sablefish (Anoplopoma fimbria). Differences in growth rates between the northern (north of Vancouver ...

  Citation × Citation Citation Abstract Copy Title: A critical examination of the ageing method for sablefish (Anoplopoma fimbria) from the U.S. west coast using edge analysis and oxytetracycline Author: O'Malley, Joseph M. This thesis evaluates the current break-and-burn ageing method for the southern stock (U.S. west coast) of sablefish (Anoplopoma fimbria). Differences in growth rates between the northern (north of Vancouver Island, BC) and southern stocks (south of Vancouver Island, BC) and results from a radiometric study conducted on fish from the southern stock suggest that the ageing method, developed from fish from the northern stock, may not be appropriate for fish in the southern stock. An edge analysis, using fish landed in Oregon, confirmed the formation of one hyaline zone annually. The timing of the deposition of the hyaline zone, May through September, is unique for fish from temperate waters. Sablefish tagged and injected with oxytetracycline (OTC) did not indicate ageing error significant enough to warrant the development of a new ageing method but some amendments to the current ageing method are recommended: do not excessively split marks in the transition zone (the area on the otolith that corresponds to the change from early fast growth to older slow growth); if multiple marks originate from the same spot on the ventral edge of the otolith, concentrate on the narrowing opaque zones when determining which marks to count as annuli; and assign age ranges or discard otoliths that display odd growth patterns. These amendments may increase the accuracy and precision of sablefish age estimates. Neither final age nor any of the auxiliary catch data (sex, size, depth, and latitude at recapture) contributed significantly to the ageing error. It is also recommended that the thin section method of preparing otoliths be used in future sablefish OTC studies. Title: A critical examination of the ageing method for sablefish (Anoplopoma fimbria) from the U.S. west coast using edge analysis and oxytetracycline Author: O'Malley, Joseph M. This thesis evaluates the current break-and-burn ageing method for the southern stock (U.S. west coast) of sablefish (Anoplopoma fimbria). Differences in growth rates between the northern (north of Vancouver Island, BC) and southern stocks (south of Vancouver Island, BC) and results from a radiometric study conducted on fish from the southern stock suggest that the ageing method, developed from fish from the northern stock, may not be appropriate for fish in the southern stock. An edge analysis, using fish landed in Oregon, confirmed the formation of one hyaline zone annually. The timing of the deposition of the hyaline zone, May through September, is unique for fish from temperate waters. Sablefish tagged and injected with oxytetracycline (OTC) did not indicate ageing error significant enough to warrant the development of a new ageing method but some amendments to the current ageing method are recommended: do not excessively split marks in the transition zone (the area on the otolith that corresponds to the change from early fast growth to older slow growth); if multiple marks originate from the same spot on the ventral edge of the otolith, concentrate on the narrowing opaque zones when determining which marks to count as annuli; and assign age ranges or discard otoliths that display odd growth patterns. These amendments may increase the accuracy and precision of sablefish age estimates. Neither final age nor any of the auxiliary catch data (sex, size, depth, and latitude at recapture) contributed significantly to the ageing error. It is also recommended that the thin section method of preparing otoliths be used in future sablefish OTC studies. Close

• 32. [Article] Relations between Preschool Attention Span-Persistence and Age 25 Educational Outcomes

  Acknowledgements: We are very grateful to Robin Corley for assistance with data management.

  Citation × Citation Citation Abstract Copy Title: Relations between Preschool Attention Span-Persistence and Age 25 Educational Outcomes Author: Stallings, Michael C., McClelland, Megan M., Piccinin, Andrea, Rhea, Sally Ann, Acock, Alan C. Acknowledgements: We are very grateful to Robin Corley for assistance with data management. Title: Relations between Preschool Attention Span-Persistence and Age 25 Educational Outcomes Author: Stallings, Michael C., McClelland, Megan M., Piccinin, Andrea, Rhea, Sally Ann, Acock, Alan C. Acknowledgements: We are very grateful to Robin Corley for assistance with data management. Close

• 33. [Article] Some socio-economic factors associated with clothing purchasing habits of a selected group of women 60 years of age and over

  The purpose of this study was to identity clothing purchasing habits of women 60 years of age and over. Data for this study were obtained from a questionnaire administered to 94 women, 60 years of age ...

  Citation × Citation Citation Abstract Copy Title: Some socio-economic factors associated with clothing purchasing habits of a selected group of women 60 years of age and over Author: Burnett, Marialyce The purpose of this study was to identity clothing purchasing habits of women 60 years of age and over. Data for this study were obtained from a questionnaire administered to 94 women, 60 years of age and over, living in Portland, Corvallis, and Eugene, Oregon. The sample was analyzed on the basis of two age groups (60 to 69 and 70 and over), three income groups (less than $999, $1000 to $1999, and $2000 and over), and three education groups (less than high school, high school, and more than high school). The chi square test was used to determine if there were relationships between clothing purchasing habits and the factors of age, income, and education of this age group. Age, income, and education were related to certain aspects of the purchasing habits of women 60 years of age and over. There was a significant relationship between the factors of age and income and whether the women enjoyed shopping for dresses. Age and education had significant relationships when analyzed with the frequency of looking at magazines, catalogues, newspapers, pattern books, or displays. There was a significant relationship between income and education and the frequency of buying a dress after first seeing it pictured in a a catalogue, a newspaper, or a window display. Age and income were important factors in whether the women wished stores carried a wider selection from which to choose. Older women have an interest in clothing. Comfort and fit were found to be the most important factors to consider in the selection of a dress. The majority of the women shopped for dresses in department stores which were located in their home towns. Most of the women shopped by themselves and preferred to do so. The majority of the women wanted their dresses to be of the current fashion trends, and many of the women were able to find styles that they liked to wear. Title: Some socio-economic factors associated with clothing purchasing habits of a selected group of women 60 years of age and over Author: Burnett, Marialyce The purpose of this study was to identity clothing purchasing habits of women 60 years of age and over. Data for this study were obtained from a questionnaire administered to 94 women, 60 years of age and over, living in Portland, Corvallis, and Eugene, Oregon. The sample was analyzed on the basis of two age groups (60 to 69 and 70 and over), three income groups (less than $999, $1000 to $1999, and $2000 and over), and three education groups (less than high school, high school, and more than high school). The chi square test was used to determine if there were relationships between clothing purchasing habits and the factors of age, income, and education of this age group. Age, income, and education were related to certain aspects of the purchasing habits of women 60 years of age and over. There was a significant relationship between the factors of age and income and whether the women enjoyed shopping for dresses. Age and education had significant relationships when analyzed with the frequency of looking at magazines, catalogues, newspapers, pattern books, or displays. There was a significant relationship between income and education and the frequency of buying a dress after first seeing it pictured in a a catalogue, a newspaper, or a window display. Age and income were important factors in whether the women wished stores carried a wider selection from which to choose. Older women have an interest in clothing. Comfort and fit were found to be the most important factors to consider in the selection of a dress. The majority of the women shopped for dresses in department stores which were located in their home towns. Most of the women shopped by themselves and preferred to do so. The majority of the women wanted their dresses to be of the current fashion trends, and many of the women were able to find styles that they liked to wear. Close

• 34. [Article] Are There Gender Differences in Stress Response in Older Adults? Findings from the Normative Aging Study

  In this study, we explored the relationships among gender, age, daily stressors, positive and negative affect, and neuroticism on cortisol outcomes in older men and women. We were particularly interested ...

  Citation × Citation Citation Abstract Copy Title: Are There Gender Differences in Stress Response in Older Adults? Findings from the Normative Aging Study Author: Proulx, Jeffrey A. In this study, we explored the relationships among gender, age, daily stressors, positive and negative affect, and neuroticism on cortisol outcomes in older men and women. We were particularly interested in whether variation in positive affect would have an effect on variation in negative affect and if this relationship would mediate the stress process. Further, we were interested in whether women would have lower cortisol outcomes as a result of this process. The participants in this study included 96 men (mean age = 79) and 65 of their wives (mean age = 75) who took part in an at-home 8- day daily diary study as part of the Normative Aging Study (NAS). This study uses data collected on four of those days in which participants provided 4 measures of salivary cortisol that we matched with a NAS version of the Daily Inventory of Stressful Events (DISE; Almeida, Wethington, & Kessler, 2002), PANAS (Watson, Clark, & Tellegen, 1988), and a 2007 assessment of neuroticism (Goldberg, 1992). Bivariate, regression, and three-level MLM-mediated-moderated analyses indicated that age had a significant effect on negative affect reports, but only for women, such that women had a downward slope in negative affect as age became higher. The rest of the analyses indicated that men and women were more alike than different in later life, although neuroticism, age, and stress had some notable main effects on affect and cortisol outcomes. These results enhance our understanding of the complex relationship between psychosocial effects and physiological stress responses in an age range rarely studied in the stress and resilience literature. Title: Are There Gender Differences in Stress Response in Older Adults? Findings from the Normative Aging Study Author: Proulx, Jeffrey A. In this study, we explored the relationships among gender, age, daily stressors, positive and negative affect, and neuroticism on cortisol outcomes in older men and women. We were particularly interested in whether variation in positive affect would have an effect on variation in negative affect and if this relationship would mediate the stress process. Further, we were interested in whether women would have lower cortisol outcomes as a result of this process. The participants in this study included 96 men (mean age = 79) and 65 of their wives (mean age = 75) who took part in an at-home 8- day daily diary study as part of the Normative Aging Study (NAS). This study uses data collected on four of those days in which participants provided 4 measures of salivary cortisol that we matched with a NAS version of the Daily Inventory of Stressful Events (DISE; Almeida, Wethington, & Kessler, 2002), PANAS (Watson, Clark, & Tellegen, 1988), and a 2007 assessment of neuroticism (Goldberg, 1992). Bivariate, regression, and three-level MLM-mediated-moderated analyses indicated that age had a significant effect on negative affect reports, but only for women, such that women had a downward slope in negative affect as age became higher. The rest of the analyses indicated that men and women were more alike than different in later life, although neuroticism, age, and stress had some notable main effects on affect and cortisol outcomes. These results enhance our understanding of the complex relationship between psychosocial effects and physiological stress responses in an age range rarely studied in the stress and resilience literature. Close

• 35. [Article] The aging endoplasmic reticulum

  Hallmarks of aging include the accumulation of aberrant proteins and a lower resistance to stresses. Because the endoplasmic reticulum (ER) functions to fold proteins and possesses unique stress sensing ...

  Citation × Citation Citation Abstract Copy Title: The aging endoplasmic reticulum Author: Dixon, Brian M. Hallmarks of aging include the accumulation of aberrant proteins and a lower resistance to stresses. Because the endoplasmic reticulum (ER) functions to fold proteins and possesses unique stress sensing pathways, the central hypothesis of this dissertation is that the ER is a target of cellular aging and significantly underlies these age-related phenotypes. This hypothesis was tested using isolated microsomes from young (3-6 mo) and old (24-26 mo) rats and a novel primary hepatocyte cell culture model that maintains the aging phenotype. The ER luminal oxidation/reduction (redox) environment, exemplified by the glutathione redox ratio (GSH:GSSG), is vital for both ER stress signaling and the regulation of ER oxidoreductase activity. Therefore, the hepatic microsomal GSH:GSSG ratio from young and old rats was determined. Our results showed that the GSH:GSSG ratio in young rats was 3.8:1 and that, in contrast to the age-related loss of GSH redox in whole liver, microsomal GSH:GSSG increased to 6.4:1 in old rats. This increase is sufficient to convert ER oxidoreductases from folding proteins to enzymes involved in protein unfolding. These results show that the ER is under an increased stress with age, yet no activation of ER stress response pathways was detected. Using the aging cell culture model noted above to examine the loss of ER stress response with age, we show that following induction of an ER stress by tunicamycin, ER-mediated "pro-apoptotic" pathways were in intact with age, but induction of "pro-survival" genes were significantly delayed. Taken together, these show that aging leads to: 1) a reductive shift in ER thiol redox, and 2) an attenuation of ER stress response. Lastly, previous work showed that (R)-alpha-lipoic acid (R-LA) restores GSH levels and redox status in aged rat livers. To determine whether R-LA also reversed the age-related changes in ER GSH redox status, young and old rats were supplemented with R-LA. Results showed that R-LA reversed both the age-related increase in the ER GSH redox state and induced protective ER stress response pathways in a manner similar to young animals. Thus, R-LA may be an effective therapeutic to maintain ER homeostatic mechanisms with age. Title: The aging endoplasmic reticulum Author: Dixon, Brian M. Hallmarks of aging include the accumulation of aberrant proteins and a lower resistance to stresses. Because the endoplasmic reticulum (ER) functions to fold proteins and possesses unique stress sensing pathways, the central hypothesis of this dissertation is that the ER is a target of cellular aging and significantly underlies these age-related phenotypes. This hypothesis was tested using isolated microsomes from young (3-6 mo) and old (24-26 mo) rats and a novel primary hepatocyte cell culture model that maintains the aging phenotype. The ER luminal oxidation/reduction (redox) environment, exemplified by the glutathione redox ratio (GSH:GSSG), is vital for both ER stress signaling and the regulation of ER oxidoreductase activity. Therefore, the hepatic microsomal GSH:GSSG ratio from young and old rats was determined. Our results showed that the GSH:GSSG ratio in young rats was 3.8:1 and that, in contrast to the age-related loss of GSH redox in whole liver, microsomal GSH:GSSG increased to 6.4:1 in old rats. This increase is sufficient to convert ER oxidoreductases from folding proteins to enzymes involved in protein unfolding. These results show that the ER is under an increased stress with age, yet no activation of ER stress response pathways was detected. Using the aging cell culture model noted above to examine the loss of ER stress response with age, we show that following induction of an ER stress by tunicamycin, ER-mediated "pro-apoptotic" pathways were in intact with age, but induction of "pro-survival" genes were significantly delayed. Taken together, these show that aging leads to: 1) a reductive shift in ER thiol redox, and 2) an attenuation of ER stress response. Lastly, previous work showed that (R)-alpha-lipoic acid (R-LA) restores GSH levels and redox status in aged rat livers. To determine whether R-LA also reversed the age-related changes in ER GSH redox status, young and old rats were supplemented with R-LA. Results showed that R-LA reversed both the age-related increase in the ER GSH redox state and induced protective ER stress response pathways in a manner similar to young animals. Thus, R-LA may be an effective therapeutic to maintain ER homeostatic mechanisms with age. Close

• 36. [Article] Aging and serum MCP-1 are associated with gut microbiome composition in a murine model

  The following information was supplied regarding data availability: BioProject ID PRJNA311095, accessions SRX1581953, SRX1581958-RX1581960, and SRX1571787-RX1571792 http://files.cgrb.oregonstate.edu/Sh...

  Citation × Citation Citation Abstract Copy Title: Aging and serum MCP-1 are associated with gut microbiome composition in a murine model Author: Conley, Melissa N., Ho, Emily, Duyck, Kyle M., Hord, Norman, Wong, Carmen P., Sharpton, Thomas J. The following information was supplied regarding data availability: BioProject ID PRJNA311095, accessions SRX1581953, SRX1581958-RX1581960, and SRX1571787-RX1571792 http://files.cgrb.oregonstate.edu/Sharpton_Lab/Papers/Conley_PeerJ_2015/ Title: Aging and serum MCP-1 are associated with gut microbiome composition in a murine model Author: Conley, Melissa N., Ho, Emily, Duyck, Kyle M., Hord, Norman, Wong, Carmen P., Sharpton, Thomas J. The following information was supplied regarding data availability: BioProject ID PRJNA311095, accessions SRX1581953, SRX1581958-RX1581960, and SRX1571787-RX1571792 http://files.cgrb.oregonstate.edu/Sharpton_Lab/Papers/Conley_PeerJ_2015/ Close

• 37. [Article] Influence of landscape-scale variables on the age and growth of coastal cutthroat trout Oncorhynchus clarkii clarkii in headwater streams

  This thesis provides the first general description of the natural variation in age structure, growth rates, and survival in headwater populations of coastal cutthroat trout Oncorhynchus clarkii clarkii ...

  Citation × Citation Citation Abstract Copy Title: Influence of landscape-scale variables on the age and growth of coastal cutthroat trout Oncorhynchus clarkii clarkii in headwater streams Author: Rehe, William G. This thesis provides the first general description of the natural variation in age structure, growth rates, and survival in headwater populations of coastal cutthroat trout Oncorhynchus clarkii clarkii from western Oregon, and a subsequent synthesis of these life-history characteristics across the range of the subspecies. Age, growth, and survival were estimated by analyzing scales from 4,250 fish collected from 37 headwater watersheds in western Oregon from 1999 to 2001. Age was validated for 234 marked and recaptured coastal cutthroat trout from two watersheds, and >94% of the scales exhibited the expected number of annuli between capture dates. Variation among readings was low (< 9%), and there was only a slight bias between readings for older fish (primarily age-5 fish). Missing first-year annuli, often observed in cutthroat trout subspecies, were not observed for these populations. Mean relative growth rates decreased with age and size. In three populations maximum age was 3 years, but in the majority, maximum age was 4 (24 populations) or 5 years (8 populations). Annual survival rates of age-3 coastal cutthroat trout (i.e., between age-2 and age-3) ranged from 23% to 65%. Akaike's Information Criterion (AIC) was used to select multiple regression models that "best" described biological response (i.e., length at age-1, mean length, and survival) to physical habitat variables. The model with January water temperature and calcium ions as predictor variables was the "best approximating model" for predicting mean length at age 1. The model with maximum pool depth and stream channel connectivity was most useful for predicting mean fish length in a watershed, and mean survival was best predicted by a model with mean July water temperature and maximum pool depth as predictor variables. Summary of range-wide life-history data for coastal cutthroat trout suggests that patterns in growth, age, and length do not follow a generalized geographic trend from north to south, and at least some differences appear to be related to life-history type. Title: Influence of landscape-scale variables on the age and growth of coastal cutthroat trout Oncorhynchus clarkii clarkii in headwater streams Author: Rehe, William G. This thesis provides the first general description of the natural variation in age structure, growth rates, and survival in headwater populations of coastal cutthroat trout Oncorhynchus clarkii clarkii from western Oregon, and a subsequent synthesis of these life-history characteristics across the range of the subspecies. Age, growth, and survival were estimated by analyzing scales from 4,250 fish collected from 37 headwater watersheds in western Oregon from 1999 to 2001. Age was validated for 234 marked and recaptured coastal cutthroat trout from two watersheds, and >94% of the scales exhibited the expected number of annuli between capture dates. Variation among readings was low (< 9%), and there was only a slight bias between readings for older fish (primarily age-5 fish). Missing first-year annuli, often observed in cutthroat trout subspecies, were not observed for these populations. Mean relative growth rates decreased with age and size. In three populations maximum age was 3 years, but in the majority, maximum age was 4 (24 populations) or 5 years (8 populations). Annual survival rates of age-3 coastal cutthroat trout (i.e., between age-2 and age-3) ranged from 23% to 65%. Akaike's Information Criterion (AIC) was used to select multiple regression models that "best" described biological response (i.e., length at age-1, mean length, and survival) to physical habitat variables. The model with January water temperature and calcium ions as predictor variables was the "best approximating model" for predicting mean length at age 1. The model with maximum pool depth and stream channel connectivity was most useful for predicting mean fish length in a watershed, and mean survival was best predicted by a model with mean July water temperature and maximum pool depth as predictor variables. Summary of range-wide life-history data for coastal cutthroat trout suggests that patterns in growth, age, and length do not follow a generalized geographic trend from north to south, and at least some differences appear to be related to life-history type. Close

• 38. [Article] An Accumulation of Senescent Cells May Contribute to Chronic Inflammation of the Mammalian Liver

  The aging process is a biological phenomenon in mammals that heavily contributes to the onset of chronic diseases. While there are many theories that attempt to explain the biological onset of aging, one ...

  Citation × Citation Citation Abstract Copy Title: An Accumulation of Senescent Cells May Contribute to Chronic Inflammation of the Mammalian Liver Author: Sugiyama, Aaron The aging process is a biological phenomenon in mammals that heavily contributes to the onset of chronic diseases. While there are many theories that attempt to explain the biological onset of aging, one emerging theory involves chronic inflammation. Chronic inflammation has been previously linked to several age-related diseases and is a known driver of chronic inflammation. To examine chronic inflammation and cellular senescence in the context of aging, we examined hepatocytes harvested from rat livers as a model. We found that rat hepatocytes not only undergo cellular senescence, but that senescent cells accumulate with age. This accumulation of senescent cells with age was also accompanied by a large increase in miR-146a and miR-155 (a seven fold and a forty-five fold change respectively) in the old rat exosomes, which indicate chronic inflammatory insult. These findings corroborate with our findings regarding an accumulation of senescent cells in the liver, and suggests that the liver undergoes an inflammatory stress. We then examined a possible treatment for cellular senescence: the drug known as dasatinib. Title: An Accumulation of Senescent Cells May Contribute to Chronic Inflammation of the Mammalian Liver Author: Sugiyama, Aaron The aging process is a biological phenomenon in mammals that heavily contributes to the onset of chronic diseases. While there are many theories that attempt to explain the biological onset of aging, one emerging theory involves chronic inflammation. Chronic inflammation has been previously linked to several age-related diseases and is a known driver of chronic inflammation. To examine chronic inflammation and cellular senescence in the context of aging, we examined hepatocytes harvested from rat livers as a model. We found that rat hepatocytes not only undergo cellular senescence, but that senescent cells accumulate with age. This accumulation of senescent cells with age was also accompanied by a large increase in miR-146a and miR-155 (a seven fold and a forty-five fold change respectively) in the old rat exosomes, which indicate chronic inflammatory insult. These findings corroborate with our findings regarding an accumulation of senescent cells in the liver, and suggests that the liver undergoes an inflammatory stress. We then examined a possible treatment for cellular senescence: the drug known as dasatinib. Close

• 39. [Article] Women's alcohol consumption : personal, familial, and geopolitical dimensions

  A sample of 1,003 women, age 22 in 1983-84 and age 27 in 1988-89, were selected from the National Longitudinal Survey of Youth. Personal, familial, and geopolitical predictors of alcohol consumption were ...

  Citation × Citation Citation Abstract Copy Title: Women's alcohol consumption : personal, familial, and geopolitical dimensions Author: Goetz, Kathryn W. A sample of 1,003 women, age 22 in 1983-84 and age 27 in 1988-89, were selected from the National Longitudinal Survey of Youth. Personal, familial, and geopolitical predictors of alcohol consumption were evaluated at each time period and longitudinally. The study integrated macro- and micro-level influences to determine their influence on individual alcohol consumption. Personal and familial were most influential. Availability of alcohol and political economy had little effect on consumption. Mother's history of alcohol abuse was more important than father's. At age 22 education, being married, and having children reduced consumption, as did a prior affiliation with a religion that proscribed the use of alcohol reduced consumption. At age 27 education, being married, and children decreased consumption, but religious affiliation and parent's consumption were not significant. While marital status at age 22 reduced drinking at that age, it lead to greater consumption at age 27. Title: Women's alcohol consumption : personal, familial, and geopolitical dimensions Author: Goetz, Kathryn W. A sample of 1,003 women, age 22 in 1983-84 and age 27 in 1988-89, were selected from the National Longitudinal Survey of Youth. Personal, familial, and geopolitical predictors of alcohol consumption were evaluated at each time period and longitudinally. The study integrated macro- and micro-level influences to determine their influence on individual alcohol consumption. Personal and familial were most influential. Availability of alcohol and political economy had little effect on consumption. Mother's history of alcohol abuse was more important than father's. At age 22 education, being married, and having children reduced consumption, as did a prior affiliation with a religion that proscribed the use of alcohol reduced consumption. At age 27 education, being married, and children decreased consumption, but religious affiliation and parent's consumption were not significant. While marital status at age 22 reduced drinking at that age, it lead to greater consumption at age 27. Close

• 40. [Article] Impact of asset usage preferences on parallel replacement decisions

  Data from a state department of transportation fleet shows that the usage of a typical asset decreases as it ages. One possible explanation for decreasing asset usage with age is operator preference for ...

  Citation × Citation Citation Abstract Copy Title: Impact of asset usage preferences on parallel replacement decisions Author: Wagner, Tristan John Data from a state department of transportation fleet shows that the usage of a typical asset decreases as it ages. One possible explanation for decreasing asset usage with age is operator preference for using the newest available asset. In this research the long-term cost and replacement implications of such a "newest first" usage practice are investigated for a fleet of similar assets with a fixed replacement age (age standard). Capital constraints on replacement are not considered. Comparisons are made to a "random" usage practice that results in constant expected usage as an asset ages. For most major cost categories, the newest first usage practice results in greater or equal costs. It is also shown that asset usage and fixed replacement age are interdependent under the newest first usage practice. The implications of this are that simple approaches found in the literature to address decreasing usage with age give incorrect results. Title: Impact of asset usage preferences on parallel replacement decisions Author: Wagner, Tristan John Data from a state department of transportation fleet shows that the usage of a typical asset decreases as it ages. One possible explanation for decreasing asset usage with age is operator preference for using the newest available asset. In this research the long-term cost and replacement implications of such a "newest first" usage practice are investigated for a fleet of similar assets with a fixed replacement age (age standard). Capital constraints on replacement are not considered. Comparisons are made to a "random" usage practice that results in constant expected usage as an asset ages. For most major cost categories, the newest first usage practice results in greater or equal costs. It is also shown that asset usage and fixed replacement age are interdependent under the newest first usage practice. The implications of this are that simple approaches found in the literature to address decreasing usage with age give incorrect results. Close

• 41. [Article] Post-K/PB younger ⁴⁰Ar–³⁹Ar ages of the Mandla lavas: Implications for the duration of the Deccan volcanism

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/lithos/

  Citation × Citation Citation Abstract Copy Title: Post-K/PB younger ⁴⁰Ar–³⁹Ar ages of the Mandla lavas: Implications for the duration of the Deccan volcanism Author: Shrivastava, J. P., Duncan, Robert A., Kashyap, Mamta This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/lithos/ Title: Post-K/PB younger ⁴⁰Ar–³⁹Ar ages of the Mandla lavas: Implications for the duration of the Deccan volcanism Author: Shrivastava, J. P., Duncan, Robert A., Kashyap, Mamta This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/lithos/ Close

• 42. [Article] Age progressive volcanism in the New England seamounts and the opening of the Central Atlantic Ocean

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Age progressive volcanism in the New England seamounts and the opening of the Central Atlantic Ocean Author: Duncan, Robert A. copyrighted by American Geophysical Union Title: Age progressive volcanism in the New England seamounts and the opening of the Central Atlantic Ocean Author: Duncan, Robert A. copyrighted by American Geophysical Union Close

• 43. [Article] Long-term patterns of diameter and basal area growth of old-growth Douglas-fir trees in western Oregon

  Diameter growth and age data collected from stumps of 505 recently cut old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees at 28 sample locations in western Oregon (U.S.A.) indicated that ...

  Citation × Citation Citation Abstract Copy Title: Long-term patterns of diameter and basal area growth of old-growth Douglas-fir trees in western Oregon Author: Poage, Nathan Jeremy, Tappeiner, John C., II Diameter growth and age data collected from stumps of 505 recently cut old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees at 28 sample locations in western Oregon (U.S.A.) indicated that rapid early and sustained growth of old Douglas-fir trees were extremely important in terms of attaining large diameters at ages 100–300 years. The diameters of the trees at ages 100–300 years (D100–D300) were strongly, positively, and linearly related to their diameters and basal area growth rates at age 50 years. Average periodic basal area increments (PAIBA) of all trees increased for the first 30–40 years and then plateaued, remaining relatively high and constant from age 50 to 300 years. Average PAIBA of the largest trees at ages 100–300 years were significantly greater by age 20 years than were those of smaller trees at ages 100–300 years. The site factors province, site class, slope, aspect, elevation, and establishment year accounted for little of the variation observed in basal area growth at age 50 years and D100–D300. The mean age range for old-growth Douglas-fir at the sample locations was wide (174 years). The hypothesis that large-diameter old-growth Douglas-fir developed at low stand densities was supported by these observations. Title: Long-term patterns of diameter and basal area growth of old-growth Douglas-fir trees in western Oregon Author: Poage, Nathan Jeremy, Tappeiner, John C., II Diameter growth and age data collected from stumps of 505 recently cut old-growth Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) trees at 28 sample locations in western Oregon (U.S.A.) indicated that rapid early and sustained growth of old Douglas-fir trees were extremely important in terms of attaining large diameters at ages 100–300 years. The diameters of the trees at ages 100–300 years (D100–D300) were strongly, positively, and linearly related to their diameters and basal area growth rates at age 50 years. Average periodic basal area increments (PAIBA) of all trees increased for the first 30–40 years and then plateaued, remaining relatively high and constant from age 50 to 300 years. Average PAIBA of the largest trees at ages 100–300 years were significantly greater by age 20 years than were those of smaller trees at ages 100–300 years. The site factors province, site class, slope, aspect, elevation, and establishment year accounted for little of the variation observed in basal area growth at age 50 years and D100–D300. The mean age range for old-growth Douglas-fir at the sample locations was wide (174 years). The hypothesis that large-diameter old-growth Douglas-fir developed at low stand densities was supported by these observations. Close

• 44. [Article] Wood density of young-growth western hemlock: relation to ring age, radial growth, stand density, and site quality

  Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. ...

  Citation × Citation Citation Abstract Copy Title: Wood density of young-growth western hemlock: relation to ring age, radial growth, stand density, and site quality Author: Marshall, D. D., Gartner, B. L., Singleton, R., DeBell, D. S. Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. Growth and wood density traits of individual rings were measured via X-ray densitometry, and relationships of ring density and its components to age and growth rate were analyzed. Ring density was highest (0.49 g/cm3) near the pith, declined to 0.40 g/cm3 at age 10, remained stable to about age 25, and then increased gradually and remained between 0.43 and 0.44 g/cm3 from age 38 to 45 and beyond. A negative influence of rapid growth on whole ring density was greatest at young ages and diminished with time, becoming nonsignificant beyond age 30. Earlywood density, latewood density, and latewood proportion were all negatively related to ring width at young ages, but by age 21–25, latewood proportion was the only component of ring density that remained significantly diminished by increased growth rate. Residual differences in wood density (after age and growth rate were considered) did not appear to be related to either stand density or site class. Overall, young-growth hemlock trees are relatively uniform in wood density and likely to be more so if grown in intensively managed stands. Title: Wood density of young-growth western hemlock: relation to ring age, radial growth, stand density, and site quality Author: Marshall, D. D., Gartner, B. L., Singleton, R., DeBell, D. S. Breast-high stem sections were sampled from 56 western hemlock (Tsuga heterophylla (Raf.) Sarg.) trees growing in 15 plots representing a wide range of tree and site conditions in northwestern Oregon. Growth and wood density traits of individual rings were measured via X-ray densitometry, and relationships of ring density and its components to age and growth rate were analyzed. Ring density was highest (0.49 g/cm3) near the pith, declined to 0.40 g/cm3 at age 10, remained stable to about age 25, and then increased gradually and remained between 0.43 and 0.44 g/cm3 from age 38 to 45 and beyond. A negative influence of rapid growth on whole ring density was greatest at young ages and diminished with time, becoming nonsignificant beyond age 30. Earlywood density, latewood density, and latewood proportion were all negatively related to ring width at young ages, but by age 21–25, latewood proportion was the only component of ring density that remained significantly diminished by increased growth rate. Residual differences in wood density (after age and growth rate were considered) did not appear to be related to either stand density or site class. Overall, young-growth hemlock trees are relatively uniform in wood density and likely to be more so if grown in intensively managed stands. Close

• 45. [Article] A comparison of body composition, body cathexis, and attitude toward obesity in women with different levels of physical activity

  The purpose of this study was to identify significant differences in body composition, body cathexis, and attitudes toward obesity of women in various age groups involved in different levels of physical exercise. A ...

  Citation × Citation Citation Abstract Copy Title: A comparison of body composition, body cathexis, and attitude toward obesity in women with different levels of physical activity Author: Lai, Shu-mei The purpose of this study was to identify significant differences in body composition, body cathexis, and attitudes toward obesity of women in various age groups involved in different levels of physical exercise. A total of 216 women, ranging in age from 17 to 64, took part in this study. They were classified into three age groups: col legeage, beyond college-age, and middle-aged, then further divided into three exercise categories: very active, moderately active, and relatively inactive. All subjects completed the Physical Activity and Body Cathexis Survey. Then the subjects submitted themselves to a series of skinfold fat measurement. In determining the subjects' feelings toward their bodies, the Secord and Jourard's Body Cathexis Scale (1953) was utilized to collect the data. Bray's Obesity Attitude Scale (1973) was employed to investigate the subjects' attitudes toward obesity. The prediction equation developed by Jackson et al. (1980) was used to determine the subjects' body density. The measurements were taken at triceps,thigh, and suprailium skinfolds. The percentage of body fat was derived from the formula of Siri's (1961). The results indicated that the middle-aged women had a higher percentage of body fat and lower amount of lean body mass than the beyond college-age women. There was, however, no significant difference between the body composition of the col lege-age and the beyond college-age women. Different levels of physical activity performed by women had significant effects on their body fat percentage and their body cathexis. Subjects in the very active level of physical exercise showed the lowest percentage of body fat and the most positive attitudes toward their bodies. Attitudes toward obesity between women, young or old, exercising or not exercising, were not significantly different. Women's obesity attitudes were not affected by either age or levels of physical activity. Title: A comparison of body composition, body cathexis, and attitude toward obesity in women with different levels of physical activity Author: Lai, Shu-mei The purpose of this study was to identify significant differences in body composition, body cathexis, and attitudes toward obesity of women in various age groups involved in different levels of physical exercise. A total of 216 women, ranging in age from 17 to 64, took part in this study. They were classified into three age groups: col legeage, beyond college-age, and middle-aged, then further divided into three exercise categories: very active, moderately active, and relatively inactive. All subjects completed the Physical Activity and Body Cathexis Survey. Then the subjects submitted themselves to a series of skinfold fat measurement. In determining the subjects' feelings toward their bodies, the Secord and Jourard's Body Cathexis Scale (1953) was utilized to collect the data. Bray's Obesity Attitude Scale (1973) was employed to investigate the subjects' attitudes toward obesity. The prediction equation developed by Jackson et al. (1980) was used to determine the subjects' body density. The measurements were taken at triceps,thigh, and suprailium skinfolds. The percentage of body fat was derived from the formula of Siri's (1961). The results indicated that the middle-aged women had a higher percentage of body fat and lower amount of lean body mass than the beyond college-age women. There was, however, no significant difference between the body composition of the col lege-age and the beyond college-age women. Different levels of physical activity performed by women had significant effects on their body fat percentage and their body cathexis. Subjects in the very active level of physical exercise showed the lowest percentage of body fat and the most positive attitudes toward their bodies. Attitudes toward obesity between women, young or old, exercising or not exercising, were not significantly different. Women's obesity attitudes were not affected by either age or levels of physical activity. Close

• 46. [Article] Sensitivity of the stock synthesis assessment model : a simulation approach

  Stock assessments for many U.S. Pacific coast groundfish stocks are developed using the catch-at-age method known as Stock Synthesis. In this work a simulation package was developed and used to evaluate ...

  Citation × Citation Citation Abstract Copy Title: Sensitivity of the stock synthesis assessment model : a simulation approach Author: Yin, Yanshui Stock assessments for many U.S. Pacific coast groundfish stocks are developed using the catch-at-age method known as Stock Synthesis. In this work a simulation package was developed and used to evaluate the sensitivity of the Stock Synthesis program. More specifically, the evaluation focused on the impacts of input data errors and stock characteristics on the accuracy and precision of Synthesis estimates. Factors examined included the length of the time series of data, the rate of natural mortality, the shape of the fishery and survey selectivity curves, the trend in the rate of fishing mortality, the recruitment pattern, and errors in the observed data for annual catch, fishing effort, fishery and survey age composition, and survey biomass indices. First, the study evaluated the sensitivity of the Stock Synthesis program applied to populations with simple multinomial age compositions. The length of the data series and sample size were the two most influential factors. Second, the study focused on populations with compound multinomial age composition, in which the age composition data were over-dispersed relative to simple multinomial samples. When the fishery age composition actually followed a compound multinomial distribution, the estimates produced by the Stock Synthesis program, which assumed simple multinomial distributions with maximum sample sizes of 400 fish, were moderately more biased and more variable. When applying Synthesis to populations whose age compositions follow compound multinomial distributions, the results from the experiments indicated that a common configuration, in which age sample sizes in the likelihood specification are limited to 400 fish per sample, probably gives age composition data too much emphasis. The experiments indicated that using 200 as the upper limit provided more accurate results than using 400. Third, the actual stock assessment of yellowfin sole (Limanda Aspera) was taken as a case study and it was found that more accurate assessment results could be achieved from a better balance in the amount of sampling effort allocated to age composition data versus survey biomass estimates. Title: Sensitivity of the stock synthesis assessment model : a simulation approach Author: Yin, Yanshui Stock assessments for many U.S. Pacific coast groundfish stocks are developed using the catch-at-age method known as Stock Synthesis. In this work a simulation package was developed and used to evaluate the sensitivity of the Stock Synthesis program. More specifically, the evaluation focused on the impacts of input data errors and stock characteristics on the accuracy and precision of Synthesis estimates. Factors examined included the length of the time series of data, the rate of natural mortality, the shape of the fishery and survey selectivity curves, the trend in the rate of fishing mortality, the recruitment pattern, and errors in the observed data for annual catch, fishing effort, fishery and survey age composition, and survey biomass indices. First, the study evaluated the sensitivity of the Stock Synthesis program applied to populations with simple multinomial age compositions. The length of the data series and sample size were the two most influential factors. Second, the study focused on populations with compound multinomial age composition, in which the age composition data were over-dispersed relative to simple multinomial samples. When the fishery age composition actually followed a compound multinomial distribution, the estimates produced by the Stock Synthesis program, which assumed simple multinomial distributions with maximum sample sizes of 400 fish, were moderately more biased and more variable. When applying Synthesis to populations whose age compositions follow compound multinomial distributions, the results from the experiments indicated that a common configuration, in which age sample sizes in the likelihood specification are limited to 400 fish per sample, probably gives age composition data too much emphasis. The experiments indicated that using 200 as the upper limit provided more accurate results than using 400. Third, the actual stock assessment of yellowfin sole (Limanda Aspera) was taken as a case study and it was found that more accurate assessment results could be achieved from a better balance in the amount of sampling effort allocated to age composition data versus survey biomass estimates. Close

• 47. [Article] Optimal harvesting of continuous age structured populations

  We investigate the optimal harvesting strategies for McKendrick type population models. Models of this type endow the population with a continuous age structure. They consist of a partial differential ...

  Citation × Citation Citation Abstract Copy Title: Optimal harvesting of continuous age structured populations Author: Smith, Steven J. We investigate the optimal harvesting strategies for McKendrick type population models. Models of this type endow the population with a continuous age structure. They consist of a partial differential equation with a boundary condition which involves an integral of the solution. We study two problems, the first concerns the yield on an infinite time interval of a linear model. It is shown that an optimal policy exists, and that it consists of harvesting at no more than three specific ages. The optimal harvesting ages are dependent on the birth and death rates, and the economic parameters of the problem. The goal of the second problem is to find the harvesting policy that maximizes the sustainable yield of a nonlinear model. It is shown that a maximal sustainable yield exists, and is accomplished by harvesting at only two ages. Title: Optimal harvesting of continuous age structured populations Author: Smith, Steven J. We investigate the optimal harvesting strategies for McKendrick type population models. Models of this type endow the population with a continuous age structure. They consist of a partial differential equation with a boundary condition which involves an integral of the solution. We study two problems, the first concerns the yield on an infinite time interval of a linear model. It is shown that an optimal policy exists, and that it consists of harvesting at no more than three specific ages. The optimal harvesting ages are dependent on the birth and death rates, and the economic parameters of the problem. The goal of the second problem is to find the harvesting policy that maximizes the sustainable yield of a nonlinear model. It is shown that a maximal sustainable yield exists, and is accomplished by harvesting at only two ages. Close

• 48. [Article] Mechanisms that influence the posttranslational modification of the GluN2B subunit in the aged brain

  Memory is essential to everyday life. As we age, deficits in memory become apparent. The toll of age-related cognitive impairment can be devastating to families and costly to society. The NMDA receptor ...

  Citation × Citation Citation Abstract Copy Title: Mechanisms that influence the posttranslational modification of the GluN2B subunit in the aged brain Author: Zamzow, Daniel R. Memory is essential to everyday life. As we age, deficits in memory become apparent. The toll of age-related cognitive impairment can be devastating to families and costly to society. The NMDA receptor is a molecule in the brain that is instrumental in the formation of memories. The receptor is particularly vulnerable to the effects of aging. Of the fourteen known subunits, the GluN2B subunit has the greatest effect on memory. The subunit also suffers from the greatest loss of expression due to aging. The present study examines the interactions of GluN2B with other proteins and quantifies the changes in posttranslational modification with age. Co-immunoprecipitation was used to measure the interaction of GluN2B with the scaffolding molecules PSD-95 and GIPC in synaptosomes from the frontal cortex of behaviorally characterized mice of three ages. The interaction between GluN2A and GluN2B was also measured. There were more PSD-95 and GluN2A molecules per GluN2B with age. The increased PSD-95/GluN2B relationship in old mice was associated with poorer memory. The GIPC/GluN2B relationship also correlated with spatial reference memory. The GluN2B/GluN2A relationship indicated an increase in triheteromeric receptors in the aged mouse, but it did not correlate with memory declines during aging. These results suggest that an age-related increase in PSD-95/GluN2B is detrimental to memory. Young and old mice were behaviorally characterized and homogenates from the frontal cortex and hippocampus were separated by differential centrifugation followed by lysis in Triton X-100. Western blots containing proteins from each cellular fraction were probed with antibodies for several proteins in the NMDA receptor complex. There was an age-related increase in p1472 in the synaptic fraction from the frontal cortex and an increase in the 115 kDa calpain-mediated cleavage product of GluN2B in the extrasynaptic fraction of old mice with good reference memory. Fyn was increased and p1336 was decreased in the synaptic membranes of poor learners. The percentage of GluN2B, GluN2A, Fyn, and PSD-95 molecules that were palmitoylated increased in an age-dependent manner in the frontal cortex, but not the hippocampus. The thioesterase, APT1, also had an age-related increase in palmitoylation in the frontal cortex. These results suggest that the palmitoylation cycle may be perturbed in the frontal cortex of aged brains and this may influence further processing of the GluN2B subunit. In the last study we attempted to lower levels of protein palmitoylation in aged mice by lowering systemic levels of palmitate. Xanthohumol is a flavonoid from hops that increases beta-oxidation in the liver thereby decreasing systemic levels of fatty acids. Mice were fed a diet supplemented with xanthohumol and behaviorally characterized in the Morris water maze. There was a small treatment effect on cognitive flexibility in the young mice, but this appeared to be a recovery from the negative effects of a phytoestrogen-deficient diet. Treatment with xanthohumol significantly lowered levels of palmitate in the plasma of old mice, but palmitoyl-CoA and protein palmitoylation was unaffected. These results suggest that there may be some promise in using xanthohumol for the treatment of metabolic syndrome, but it may not be suitable for lowering levels of protein palmitoylation in the brain. These results presented in this thesis suggest that an age-related increase in palmitoylation of GluN2B and NMDA receptor effector proteins in the brain may affect the function of neurons in the frontal cortex in two ways. First, increased p1472 enhances clustering of GluN2B-containing NMDA receptors on the synaptic membrane, thereby preserving memory in some old mice. Second, an age-related increase in the calpain-mediated cleavage of GluN2B may eventually lead to increased cell death. Interventions that reduce systemic levels of palmitate may not be effective in treating memory deficits. What is needed is a greater understanding of the mechanisms that govern the palmitoylation cycle in brain in order to design more targeted interventions in the future. Title: Mechanisms that influence the posttranslational modification of the GluN2B subunit in the aged brain Author: Zamzow, Daniel R. Memory is essential to everyday life. As we age, deficits in memory become apparent. The toll of age-related cognitive impairment can be devastating to families and costly to society. The NMDA receptor is a molecule in the brain that is instrumental in the formation of memories. The receptor is particularly vulnerable to the effects of aging. Of the fourteen known subunits, the GluN2B subunit has the greatest effect on memory. The subunit also suffers from the greatest loss of expression due to aging. The present study examines the interactions of GluN2B with other proteins and quantifies the changes in posttranslational modification with age. Co-immunoprecipitation was used to measure the interaction of GluN2B with the scaffolding molecules PSD-95 and GIPC in synaptosomes from the frontal cortex of behaviorally characterized mice of three ages. The interaction between GluN2A and GluN2B was also measured. There were more PSD-95 and GluN2A molecules per GluN2B with age. The increased PSD-95/GluN2B relationship in old mice was associated with poorer memory. The GIPC/GluN2B relationship also correlated with spatial reference memory. The GluN2B/GluN2A relationship indicated an increase in triheteromeric receptors in the aged mouse, but it did not correlate with memory declines during aging. These results suggest that an age-related increase in PSD-95/GluN2B is detrimental to memory. Young and old mice were behaviorally characterized and homogenates from the frontal cortex and hippocampus were separated by differential centrifugation followed by lysis in Triton X-100. Western blots containing proteins from each cellular fraction were probed with antibodies for several proteins in the NMDA receptor complex. There was an age-related increase in p1472 in the synaptic fraction from the frontal cortex and an increase in the 115 kDa calpain-mediated cleavage product of GluN2B in the extrasynaptic fraction of old mice with good reference memory. Fyn was increased and p1336 was decreased in the synaptic membranes of poor learners. The percentage of GluN2B, GluN2A, Fyn, and PSD-95 molecules that were palmitoylated increased in an age-dependent manner in the frontal cortex, but not the hippocampus. The thioesterase, APT1, also had an age-related increase in palmitoylation in the frontal cortex. These results suggest that the palmitoylation cycle may be perturbed in the frontal cortex of aged brains and this may influence further processing of the GluN2B subunit. In the last study we attempted to lower levels of protein palmitoylation in aged mice by lowering systemic levels of palmitate. Xanthohumol is a flavonoid from hops that increases beta-oxidation in the liver thereby decreasing systemic levels of fatty acids. Mice were fed a diet supplemented with xanthohumol and behaviorally characterized in the Morris water maze. There was a small treatment effect on cognitive flexibility in the young mice, but this appeared to be a recovery from the negative effects of a phytoestrogen-deficient diet. Treatment with xanthohumol significantly lowered levels of palmitate in the plasma of old mice, but palmitoyl-CoA and protein palmitoylation was unaffected. These results suggest that there may be some promise in using xanthohumol for the treatment of metabolic syndrome, but it may not be suitable for lowering levels of protein palmitoylation in the brain. These results presented in this thesis suggest that an age-related increase in palmitoylation of GluN2B and NMDA receptor effector proteins in the brain may affect the function of neurons in the frontal cortex in two ways. First, increased p1472 enhances clustering of GluN2B-containing NMDA receptors on the synaptic membrane, thereby preserving memory in some old mice. Second, an age-related increase in the calpain-mediated cleavage of GluN2B may eventually lead to increased cell death. Interventions that reduce systemic levels of palmitate may not be effective in treating memory deficits. What is needed is a greater understanding of the mechanisms that govern the palmitoylation cycle in brain in order to design more targeted interventions in the future. Close

• 49. [Article] Aging in place : a contemporary social phenomenon

  Most aging individuals prefer to remain in a self-determined home environment, and generally aging adults want to remain in the same home or same community. The benefits of remaining in a self-determined ...

  Citation × Citation Citation Abstract Copy Title: Aging in place : a contemporary social phenomenon Author: Lee, Megan (Megan Elizabeth) Most aging individuals prefer to remain in a self-determined home environment, and generally aging adults want to remain in the same home or same community. The benefits of remaining in a self-determined private home environment while aging have been established. Because individuals present a diversity of needs, it takes interdisciplinary and multifaceted approaches with options to keep older adults in their communities. Aging in place (AIP) represents an interdisciplinary approach to creating options that facilitate remaining in a self-determine environment. The purpose of this research was to examine the current state of the interdisciplinary concept aging in place (AIP). The need to understand AIP is more globally relevant as the U.S. becomes an aging society facing rapid change due to technology, globalization, and mobility. Guided by the tenants of theory development, and the ecological model of housing choice, two manuscripts were developed focusing on the current state of AIP. The first research study titled, An Evolutionary Concept Analysis: Aging in Place, used the content analysis method to examine the concept across diverse disciplines. A derived definition was developed that includes research, practice, policy, and those individuals involved in the aging process. The definition reflects the contemporary state of AIP and can be used for theory development and to unify all users of the AIP concept. The second research study titled, The Current State of Older Women Aging in Place in Oregon, used qualitative case study methods to examine seven cases of aging in place. The aim of the project was to examine seven women’s current and past experiences, and the dynamic process of aging in place in a self-determined private home environment. Two common themes were identified (1) The AIP reflects the woman’s process of self-preserving actions that maintain current AIP independence, and (2) AIP situational independence suggests that the participants’ pathways to their current AIP began after they each experienced an individualized trigger event. The findings have theoretical and practice implications that provide a comprehensive and interdisciplinary approach to identifying the current status of AIP and the development of options that facilitate the AIP process. Title: Aging in place : a contemporary social phenomenon Author: Lee, Megan (Megan Elizabeth) Most aging individuals prefer to remain in a self-determined home environment, and generally aging adults want to remain in the same home or same community. The benefits of remaining in a self-determined private home environment while aging have been established. Because individuals present a diversity of needs, it takes interdisciplinary and multifaceted approaches with options to keep older adults in their communities. Aging in place (AIP) represents an interdisciplinary approach to creating options that facilitate remaining in a self-determine environment. The purpose of this research was to examine the current state of the interdisciplinary concept aging in place (AIP). The need to understand AIP is more globally relevant as the U.S. becomes an aging society facing rapid change due to technology, globalization, and mobility. Guided by the tenants of theory development, and the ecological model of housing choice, two manuscripts were developed focusing on the current state of AIP. The first research study titled, An Evolutionary Concept Analysis: Aging in Place, used the content analysis method to examine the concept across diverse disciplines. A derived definition was developed that includes research, practice, policy, and those individuals involved in the aging process. The definition reflects the contemporary state of AIP and can be used for theory development and to unify all users of the AIP concept. The second research study titled, The Current State of Older Women Aging in Place in Oregon, used qualitative case study methods to examine seven cases of aging in place. The aim of the project was to examine seven women’s current and past experiences, and the dynamic process of aging in place in a self-determined private home environment. Two common themes were identified (1) The AIP reflects the woman’s process of self-preserving actions that maintain current AIP independence, and (2) AIP situational independence suggests that the participants’ pathways to their current AIP began after they each experienced an individualized trigger event. The findings have theoretical and practice implications that provide a comprehensive and interdisciplinary approach to identifying the current status of AIP and the development of options that facilitate the AIP process. Close

• 50. [Article] A heuristic causal model of factors affecting age integrated/age segregated neighborhood preference during retirement

  The purpose of this research was to determine a causal model of factors affecting age integrated/age segregated neighborhood preference during retirement. Data were anaLzed for 1299 preretirers in four ...

  Citation × Citation Citation Abstract Copy Title: A heuristic causal model of factors affecting age integrated/age segregated neighborhood preference during retirement Author: Malroutu, Yamini Lakshmi The purpose of this research was to determine a causal model of factors affecting age integrated/age segregated neighborhood preference during retirement. Data were anaLzed for 1299 preretirers in four states: Idaho, Michigan, Oregon, and Utah, collected in a mail survey in 1990 by the Western Regional Agricultural Experiment Station Committee (W-176). Preference for age integrated/age segregated neighborhoods during the first ten years of retirement was directly influenced by tenure preference (p=.00, B=.210). Those who preferred homeownership during retirement chose age integrated neighborhoods during their first ten years of retirement. Preference for age integrated/age segregated neighborhoods after ten years of retirement was significantly influenced by family income (P=.03, B=.096), suitability of home size (p=.02, B=.094), and tenure preference (p=.00, B=.155). Those who were economically well off indicated a predisposition for age integrated neighborhoods as did those who preferred homeownership and those who felt they had the right size homes for retirement. Indirect effects were also observed among the exogenous and intervening variables and age integrated/age segregated neighborhood preference during the first ten years and after ten years of retirement. Older preretirees preferred to retire in the community (p=.00, B= .125) and this preference for the present community influenced the choice of preferred homeownership during retirement (p=.00, B=.205). Those who favored homeownership indicated a preference for age integrated neighborhoods both during the first ten years (p=.00, B=.210) and after ten years of retirement (p=.00, B=.155). These interrelationships lead to the assumption that older respondents prefer to age in place as they showed a preference to retire in the present community and for homeownership. The findings of this research will be beneficial and of interest to retirees who are trying to create a suitable and affordable environment for themselves and communities will be enriched by their participation in economic and service functions. Community developers who are striving to boost their local economies can attract retirees by providing to the needs of the elderly consumers. Title: A heuristic causal model of factors affecting age integrated/age segregated neighborhood preference during retirement Author: Malroutu, Yamini Lakshmi The purpose of this research was to determine a causal model of factors affecting age integrated/age segregated neighborhood preference during retirement. Data were anaLzed for 1299 preretirers in four states: Idaho, Michigan, Oregon, and Utah, collected in a mail survey in 1990 by the Western Regional Agricultural Experiment Station Committee (W-176). Preference for age integrated/age segregated neighborhoods during the first ten years of retirement was directly influenced by tenure preference (p=.00, B=.210). Those who preferred homeownership during retirement chose age integrated neighborhoods during their first ten years of retirement. Preference for age integrated/age segregated neighborhoods after ten years of retirement was significantly influenced by family income (P=.03, B=.096), suitability of home size (p=.02, B=.094), and tenure preference (p=.00, B=.155). Those who were economically well off indicated a predisposition for age integrated neighborhoods as did those who preferred homeownership and those who felt they had the right size homes for retirement. Indirect effects were also observed among the exogenous and intervening variables and age integrated/age segregated neighborhood preference during the first ten years and after ten years of retirement. Older preretirees preferred to retire in the community (p=.00, B= .125) and this preference for the present community influenced the choice of preferred homeownership during retirement (p=.00, B=.205). Those who favored homeownership indicated a preference for age integrated neighborhoods both during the first ten years (p=.00, B=.210) and after ten years of retirement (p=.00, B=.155). These interrelationships lead to the assumption that older respondents prefer to age in place as they showed a preference to retire in the present community and for homeownership. The findings of this research will be beneficial and of interest to retirees who are trying to create a suitable and affordable environment for themselves and communities will be enriched by their participation in economic and service functions. Community developers who are striving to boost their local economies can attract retirees by providing to the needs of the elderly consumers. Close

• 51. [Article] Influence of aging and behavioral experience on expression of GluN1 splice variants of the NMDA receptor in prefrontal cortex of mice brain

  As the aging population continues to grow the world over, age related complications become more and more apparent among the elderly population. One such complication is age associated memory impairment, ...

  Citation × Citation Citation Abstract Copy Title: Influence of aging and behavioral experience on expression of GluN1 splice variants of the NMDA receptor in prefrontal cortex of mice brain Author: Das, Siba Ranjan As the aging population continues to grow the world over, age related complications become more and more apparent among the elderly population. One such complication is age associated memory impairment, which makes the elderly more dependent on caregivers early on. NMDA receptors in the brain are important for memory formation, consolidation and retrieval. Expression of NMDA receptors declines with age, which is associated with declines in memory observed during aging. Age-related changes in the protein and mRNA expression of some of the splice forms of the GluN1 (GluN1, NR1) subunit of the NMDA receptor have been seen in mice and rats. The present study was designed to determine whether individual splice forms of the GluN1 subunit of the NMDA receptor within prefrontal / frontal cortical regions contribute to memory deficits during aging and whether experience in learning tasks can influence the expression of the splice forms. mRNA expression of 4 splice forms GluN1[subscript X11], GluN1[subscript X10], GluN1[subscript 0XX] and GluN1[subscript 1XX] (GluN1-1, GluN1-3, GluN1-a and GluN1-b, respectively) and mRNA for all known splice forms (GluN1-pan) were examined by in situ hybridization. mRNA for the C-terminal splice forms, GluN1[subscript X11] (GluN1-1; +C1 and +C2 cassettes) and GluN1[subscript X10] (GluN1-3; +C1 and +C2'), showed significant declines during aging in several brain regions even though overall GluN1-pan mRNA expression was not significantly affected by aging. This work provides evidence that these splice forms are more influenced by aging than the subunit as a whole. There was an increase in the expression of GluN1[subscript 0XX] (GluN1-a; -N1 cassette) splice form in the behaviorally-experienced old mice relative to the younger groups. Old mice with the highest levels of mRNA expression for the GluN1[subscript 0XX] (GluN1-a) splice form in orbital cortex showed the best performances in spatial working and reference memory tasks, but the poorest performances in a cued, associative learning task. These results suggest that the GluN1[subscript 0XX] subunit splice variant may be important for spatial memory performance in the old animals. Protein expression of GluN1 subunits containing C-terminal cassettes C2 or C2' were observed to decline with increasing age, regardless of experience. In middle-age animals, higher expressions of the GluN1 subunit and C2' cassette proteins were associated with good reference memory on initial search. In the aged animals, higher protein expression of GluN1 subunits containing C1 cassettes and the whole population of GluN1 subunits were found to be associated with better performance in the final phase of probe trials but this appeared to be due to perseveration or delays in applying an accurate search. These results provide support for the theory that there is heterogeneity in the effect of aging on the expression of the GluN1 subunits containing different splice cassettes. It also suggests that the GluN1 subunit might be most important for good reference memory during middle age. The next study was undertaken to determine if the GluN1[subscript 0XX] splice form is required for good performance in reference memory tasks in young mice. Mice were injected with 5µl of either siRNA specific to GluN1[subscript 0XX], control siRNA or vehicle alone into ventro-lateral orbital regions of both sides of the brain using a stereotaxic apparatus. A fourth group of mice did not receive any injections. Five days post-injection, mice were tested for their performance in a spatial reference memory task for 4 days using the Morris water maze. There was a 10 -19% reduction in GluN1[subscript 0XX] splice variant expression for mice after siRNA treatment in ventro-lateral orbital regions of the brain. Decline in performance in the first half of reference memory were observed in the mice receiving siRNA specific for GluN1[subscript 0XX] splice form, as compared to the mice injected with control siRNA and/or vehicle. These results suggest an important role of the GluN1[subscript 0XX] splice variant in orbital regions for spatial reference memory acquisition and/or consolidation in the early stages of memory training. These results suggest that there is a complex interaction between GluN1 splice form expression and performance of memory tasks during aging. Future studies designed to differentiate between involvement of splice variants in particular stages of memory formation would be helpful. Title: Influence of aging and behavioral experience on expression of GluN1 splice variants of the NMDA receptor in prefrontal cortex of mice brain Author: Das, Siba Ranjan As the aging population continues to grow the world over, age related complications become more and more apparent among the elderly population. One such complication is age associated memory impairment, which makes the elderly more dependent on caregivers early on. NMDA receptors in the brain are important for memory formation, consolidation and retrieval. Expression of NMDA receptors declines with age, which is associated with declines in memory observed during aging. Age-related changes in the protein and mRNA expression of some of the splice forms of the GluN1 (GluN1, NR1) subunit of the NMDA receptor have been seen in mice and rats. The present study was designed to determine whether individual splice forms of the GluN1 subunit of the NMDA receptor within prefrontal / frontal cortical regions contribute to memory deficits during aging and whether experience in learning tasks can influence the expression of the splice forms. mRNA expression of 4 splice forms GluN1[subscript X11], GluN1[subscript X10], GluN1[subscript 0XX] and GluN1[subscript 1XX] (GluN1-1, GluN1-3, GluN1-a and GluN1-b, respectively) and mRNA for all known splice forms (GluN1-pan) were examined by in situ hybridization. mRNA for the C-terminal splice forms, GluN1[subscript X11] (GluN1-1; +C1 and +C2 cassettes) and GluN1[subscript X10] (GluN1-3; +C1 and +C2'), showed significant declines during aging in several brain regions even though overall GluN1-pan mRNA expression was not significantly affected by aging. This work provides evidence that these splice forms are more influenced by aging than the subunit as a whole. There was an increase in the expression of GluN1[subscript 0XX] (GluN1-a; -N1 cassette) splice form in the behaviorally-experienced old mice relative to the younger groups. Old mice with the highest levels of mRNA expression for the GluN1[subscript 0XX] (GluN1-a) splice form in orbital cortex showed the best performances in spatial working and reference memory tasks, but the poorest performances in a cued, associative learning task. These results suggest that the GluN1[subscript 0XX] subunit splice variant may be important for spatial memory performance in the old animals. Protein expression of GluN1 subunits containing C-terminal cassettes C2 or C2' were observed to decline with increasing age, regardless of experience. In middle-age animals, higher expressions of the GluN1 subunit and C2' cassette proteins were associated with good reference memory on initial search. In the aged animals, higher protein expression of GluN1 subunits containing C1 cassettes and the whole population of GluN1 subunits were found to be associated with better performance in the final phase of probe trials but this appeared to be due to perseveration or delays in applying an accurate search. These results provide support for the theory that there is heterogeneity in the effect of aging on the expression of the GluN1 subunits containing different splice cassettes. It also suggests that the GluN1 subunit might be most important for good reference memory during middle age. The next study was undertaken to determine if the GluN1[subscript 0XX] splice form is required for good performance in reference memory tasks in young mice. Mice were injected with 5µl of either siRNA specific to GluN1[subscript 0XX], control siRNA or vehicle alone into ventro-lateral orbital regions of both sides of the brain using a stereotaxic apparatus. A fourth group of mice did not receive any injections. Five days post-injection, mice were tested for their performance in a spatial reference memory task for 4 days using the Morris water maze. There was a 10 -19% reduction in GluN1[subscript 0XX] splice variant expression for mice after siRNA treatment in ventro-lateral orbital regions of the brain. Decline in performance in the first half of reference memory were observed in the mice receiving siRNA specific for GluN1[subscript 0XX] splice form, as compared to the mice injected with control siRNA and/or vehicle. These results suggest an important role of the GluN1[subscript 0XX] splice variant in orbital regions for spatial reference memory acquisition and/or consolidation in the early stages of memory training. These results suggest that there is a complex interaction between GluN1 splice form expression and performance of memory tasks during aging. Future studies designed to differentiate between involvement of splice variants in particular stages of memory formation would be helpful. Close

• 52. [Article] Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain

  This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291525-2027.

  Citation × Citation Citation Abstract Copy Title: Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain Author: Jokat, Wilfried, O'Connor, John M., Haase, Karsten M., Stoffers, Peter, Steinberger, Bernhard, Garbe-Schönberg, Dieter, Wijbrans, Jan R., Regelous, Marcel, Koppers, Anthony A. P. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291525-2027. Title: Constraints on past plate and mantle motion from new ages for the Hawaiian-Emperor Seamount Chain Author: Jokat, Wilfried, O'Connor, John M., Haase, Karsten M., Stoffers, Peter, Steinberger, Bernhard, Garbe-Schönberg, Dieter, Wijbrans, Jan R., Regelous, Marcel, Koppers, Anthony A. P. This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291525-2027. Close

• 53. [Article] Personality, Self-Perceptions, and Daily Variability in Perceived Usefulness Among Older Adults

  This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.

  Citation × Citation Citation Abstract Copy Title: Personality, Self-Perceptions, and Daily Variability in Perceived Usefulness Among Older Adults Author: Mejía, Shannon T., Allen, Pamela M., Hooker, Karen This article may not exactly replicate the final version published in the APA journal. It is not the copy of record. Title: Personality, Self-Perceptions, and Daily Variability in Perceived Usefulness Among Older Adults Author: Mejía, Shannon T., Allen, Pamela M., Hooker, Karen This article may not exactly replicate the final version published in the APA journal. It is not the copy of record. Close

• 54. [Article] Evaluation of Three Aging Techniques and Back-calculated Growth for Introduced Blue Catfish from Lake Oconee, Georgia

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Eagle Hill ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of Three Aging Techniques and Back-calculated Growth for Introduced Blue Catfish from Lake Oconee, Georgia Author: Jennings, Cecil A., Homer, Michael D. Jr, Peterson, James T. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Eagle Hill Institute and can be found at: http://www.eaglehill.us/programs/journals/sena/southeastern-naturalist.shtml Title: Evaluation of Three Aging Techniques and Back-calculated Growth for Introduced Blue Catfish from Lake Oconee, Georgia Author: Jennings, Cecil A., Homer, Michael D. Jr, Peterson, James T. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Eagle Hill Institute and can be found at: http://www.eaglehill.us/programs/journals/sena/southeastern-naturalist.shtml Close

• 55. [Article] Determining the cost of old-growth set-asides on the OSU college forest

  The objectives for the use of the Oregon State University college forest include providing both facilities for research and teaching, and providing funding through timber harvest. The older age-classes ...

  Citation × Citation Citation Abstract Copy Title: Determining the cost of old-growth set-asides on the OSU college forest Author: Birch, Kevin R. The objectives for the use of the Oregon State University college forest include providing both facilities for research and teaching, and providing funding through timber harvest. The older age-classes of the forest are valuable for attaining both objectives. The opportunities and costs of removing acreage in the older age classes from the timber harvest base were examined. Harvest schedules were developed using a model II linear programming formulation with the OSU Forestry Model. The harvest schedules used the current management policies of the forest managers and different levels of set-asides with a non-declining even flow of volume constraining the harvest level. The current rotation age of 90 years was found to be constraining the harvest level in the first four decades, therefore a set of harvest scheduling runs using a 60 year rotation age were done. Using the existing management policies and a rotation age of 90 years, the managers of the college forest can set-aside the oldest 686 acres of the forest without reducing the current harvest level. The cost of the set-sides (calculated as the difference between present net values of 100 year harvest schedules with and without the acreage removed) was between $5500 and $4500 per acre depending on the amount of acreage removed. The change in rotation age produced only slight changes in the cost of set-asides. The current harvest level could be increased immediately to a level near long-term sustained yield by using a rotation age of 60 years. This would increase the present net value of the harvest schedule by about $5 million. By using a rotation age of 90, more age classes can be represented on the forest over time. After four decades the harvest volume can be increased to the long-term sustained yield level. At that time the harvest would be obtained from fewer acres than if the forest was on a 60 year rotation. Title: Determining the cost of old-growth set-asides on the OSU college forest Author: Birch, Kevin R. The objectives for the use of the Oregon State University college forest include providing both facilities for research and teaching, and providing funding through timber harvest. The older age-classes of the forest are valuable for attaining both objectives. The opportunities and costs of removing acreage in the older age classes from the timber harvest base were examined. Harvest schedules were developed using a model II linear programming formulation with the OSU Forestry Model. The harvest schedules used the current management policies of the forest managers and different levels of set-asides with a non-declining even flow of volume constraining the harvest level. The current rotation age of 90 years was found to be constraining the harvest level in the first four decades, therefore a set of harvest scheduling runs using a 60 year rotation age were done. Using the existing management policies and a rotation age of 90 years, the managers of the college forest can set-aside the oldest 686 acres of the forest without reducing the current harvest level. The cost of the set-sides (calculated as the difference between present net values of 100 year harvest schedules with and without the acreage removed) was between $5500 and $4500 per acre depending on the amount of acreage removed. The change in rotation age produced only slight changes in the cost of set-asides. The current harvest level could be increased immediately to a level near long-term sustained yield by using a rotation age of 60 years. This would increase the present net value of the harvest schedule by about $5 million. By using a rotation age of 90, more age classes can be represented on the forest over time. After four decades the harvest volume can be increased to the long-term sustained yield level. At that time the harvest would be obtained from fewer acres than if the forest was on a 60 year rotation. Close

• 56. [Article] Effects of maternal age on reproductive success in black rockfish, Sebastes melanops

  From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black ...

  Citation × Citation Citation Abstract Copy Title: Effects of maternal age on reproductive success in black rockfish, Sebastes melanops Author: Bobko, Stephen J. From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black rockfish extruded larvae earlier in the season, followed by progressively younger fish. Each year, beginning in May, I collected young-of-the-year (YOY) benthic juveniles that settled out in nearshore waters and determined their birthdates from counts of daily rings of lapillar otoliths. I compared the birthdate distribution of juvenile survivors to the age-specific temporal distribution of larval production to estimate the contribution of each adult female age group, ages 6-8, 9-11, 12-14, and 15+ to juvenile recruitment. The results from 1996 show a disproportionately greater contribution to benthic YOY recruitment by older fish. 1997 results show a relatively even contribution among maternal age groups. In 1998 most of the YOY recruits came from younger fish extruding larvae late in the season. I then examined larvae per recruit (LPR) models to evaluate the effects of fishing mortality on spawning potential of black rockfish, incorporating my estimates of age-specific maternal reproductive success. When it is evident that certain age groups are more successful at reproducing, as observed in black rockfish, changes in that population's age composition must be considered beyond simply reducing the estimate of total larval production. Title: Effects of maternal age on reproductive success in black rockfish, Sebastes melanops Author: Bobko, Stephen J. From 1996 through 1998 I collected mature female black rockfish off Oregon and examined ovaries and otoliths to estimate weekly, age-specific larval production. In all reproductive seasons, older black rockfish extruded larvae earlier in the season, followed by progressively younger fish. Each year, beginning in May, I collected young-of-the-year (YOY) benthic juveniles that settled out in nearshore waters and determined their birthdates from counts of daily rings of lapillar otoliths. I compared the birthdate distribution of juvenile survivors to the age-specific temporal distribution of larval production to estimate the contribution of each adult female age group, ages 6-8, 9-11, 12-14, and 15+ to juvenile recruitment. The results from 1996 show a disproportionately greater contribution to benthic YOY recruitment by older fish. 1997 results show a relatively even contribution among maternal age groups. In 1998 most of the YOY recruits came from younger fish extruding larvae late in the season. I then examined larvae per recruit (LPR) models to evaluate the effects of fishing mortality on spawning potential of black rockfish, incorporating my estimates of age-specific maternal reproductive success. When it is evident that certain age groups are more successful at reproducing, as observed in black rockfish, changes in that population's age composition must be considered beyond simply reducing the estimate of total larval production. Close

• 57. [Article] An analysis of the attitudes of traditional-aged and non-traditional-aged females about computers in word processing classes at Oregon's community colleges

  Today's office worker is being expected to operate computers in order to increase office productivity. While learning the new technology is a positive challenge for most people, some students experience ...

  Citation × Citation Citation Abstract Copy Title: An analysis of the attitudes of traditional-aged and non-traditional-aged females about computers in word processing classes at Oregon's community colleges Author: Fletcher, Judith Ann Today's office worker is being expected to operate computers in order to increase office productivity. While learning the new technology is a positive challenge for most people, some students experience a negative computer attitude when faced with computer training. This study sought to determine if there were significant differences about computer attitudes among females enrolled in introductory computer word processing classes in Oregon's community colleges. A sample of 125 traditional-aged females and 125 non-traditional-aged females was surveyed using the Computer Attitude Scale (CAS) developed by Brenda Loyd and Clarice Gressard. A t-test was used to compare groups on the CAS total scale and four subscales. No significant difference at the .05 level was found between the two groups on the total scores in the CAS. No significant differences were found on the two subscales: Computer Confidence and Computer Usefulness. However, on the Computer Anxiety Subscale, the non-traditional-aged group scored significantly lower than the traditional-aged group. There was also a significant difference on the Computer Liking subscale with the traditional-aged group scoring lower than the non-traditional-aged group. The implications of the study resulted in the recommendations that the instructors be alert to students' attitudes about computers as they are exposed to new office technology and that those instructors who gather, design, and scientifically test successful strategies in relieving negative attitudes share their methods with other teachers. It was also recommended that a correlation study between computer attitudes and word processing performance be made. Further recommendations for scientific studies included students' attitudes about technology other than word processing, the affect of age difference on students' attitudes, the affect of the amount of time of previous employment of students' attitudes, and the affect of previous computer experience on students' attitudes. Title: An analysis of the attitudes of traditional-aged and non-traditional-aged females about computers in word processing classes at Oregon's community colleges Author: Fletcher, Judith Ann Today's office worker is being expected to operate computers in order to increase office productivity. While learning the new technology is a positive challenge for most people, some students experience a negative computer attitude when faced with computer training. This study sought to determine if there were significant differences about computer attitudes among females enrolled in introductory computer word processing classes in Oregon's community colleges. A sample of 125 traditional-aged females and 125 non-traditional-aged females was surveyed using the Computer Attitude Scale (CAS) developed by Brenda Loyd and Clarice Gressard. A t-test was used to compare groups on the CAS total scale and four subscales. No significant difference at the .05 level was found between the two groups on the total scores in the CAS. No significant differences were found on the two subscales: Computer Confidence and Computer Usefulness. However, on the Computer Anxiety Subscale, the non-traditional-aged group scored significantly lower than the traditional-aged group. There was also a significant difference on the Computer Liking subscale with the traditional-aged group scoring lower than the non-traditional-aged group. The implications of the study resulted in the recommendations that the instructors be alert to students' attitudes about computers as they are exposed to new office technology and that those instructors who gather, design, and scientifically test successful strategies in relieving negative attitudes share their methods with other teachers. It was also recommended that a correlation study between computer attitudes and word processing performance be made. Further recommendations for scientific studies included students' attitudes about technology other than word processing, the affect of age difference on students' attitudes, the affect of the amount of time of previous employment of students' attitudes, and the affect of previous computer experience on students' attitudes. Close

• 58. [Article] Histologic and Morphometric Evaluation of Testes of Feral Tom Kittens and Cats

  Background: Even with numerous successful Trap-Neuter-Release programs, feral cat populations continue to grow. Our laboratory is interested in determining if an underlying biological cause exists for ...

  Citation × Citation Citation Abstract Copy Title: Histologic and Morphometric Evaluation of Testes of Feral Tom Kittens and Cats Author: Bohrer, Ellie R., Mihalyo, Anna Background: Even with numerous successful Trap-Neuter-Release programs, feral cat populations continue to grow. Our laboratory is interested in determining if an underlying biological cause exists for the exuberant reproductive success in this once domestic subspecies. An earlier age for developing reproductive capacity (onset of spermatogenesis in males) may be one factor. For domestic toms, puberty is reported to occur around 8 months of age. Previous work by our laboratory has shown that normal morphologic sperm are present in vas deferens secretions of feral toms before 6 months of age. Therefore, our hypothesis was that in feral toms the onset of spermatogenesis occurred before 6 months of age. The study objective was to histologically evaluate testes from weanling (2 months of age) through adulthood (24 months of age) to determine when the onset of spermatogenesis occurs in feral toms. Methods: Feral toms were presented for castration at a local Humane Society during August-October 2014. Age was determined by records provided from feral cat colony managers and confirmed with dental eruption patterns. The age groups were: 2-2.5 months (weanling; n=6), 3-4 months (juvenile; n=6), 5-6 months (pubertal; n=6), and 12-24 months (adult; n=6). General anesthesia was induced and a routine open castration was performed. Both testicles from each cat were hemi-sectioned, formalin-fixed, paraffin-embedded, cut into sections (6 µm), and stained with hematoxylin and eosin. The slides were evaluated by a single observer (EB) blinded to age group using bright field microscopy (200X). Evidence of spermatogenesis was determined on the basis of presence of spermatozoa in the seminiferous tubule lumen. In addition, perpendicular diameters measured from 5 tubules for each testis were averaged and mean ± SD was determined for each age group. Tubular diameter was compared using a Student’s t test where p < 0.05 was defined as significant. The presence of spermatozoa in the lumen was compared using a Chi-square test. Results: Evidence of spermatogenesis in weanling, juvenile, pubertal, and adult toms was 0%, 17%, 67%, and 100%, respectively (p < 0.05 between successive age groups). The seminiferous tubular diameter was significantly larger in each successive age group (weanlings 88.10 ± 10.88 µm; juveniles 109.8 ± 8.89 µm; pubertal 142.2 ± 16.89 µm; adult 237.90 ± 52.45 µm). Discussion: Juvenile feral toms in the current study had significantly wider tubular diameter than previously reported for domestic toms under 5 months of age (86 µm), which supports our hypothesis that spermatogenesis is occurring at an earlier age in ferals. However, the time of year the previous measurements in domestics was not reported. If these measurements were made outside of the breeding season, this may explain why the tubular diameters were smaller. Future studies are planned to determine if folliculogenesis occurs earlier in queens as well. Title: Histologic and Morphometric Evaluation of Testes of Feral Tom Kittens and Cats Author: Bohrer, Ellie R., Mihalyo, Anna Background: Even with numerous successful Trap-Neuter-Release programs, feral cat populations continue to grow. Our laboratory is interested in determining if an underlying biological cause exists for the exuberant reproductive success in this once domestic subspecies. An earlier age for developing reproductive capacity (onset of spermatogenesis in males) may be one factor. For domestic toms, puberty is reported to occur around 8 months of age. Previous work by our laboratory has shown that normal morphologic sperm are present in vas deferens secretions of feral toms before 6 months of age. Therefore, our hypothesis was that in feral toms the onset of spermatogenesis occurred before 6 months of age. The study objective was to histologically evaluate testes from weanling (2 months of age) through adulthood (24 months of age) to determine when the onset of spermatogenesis occurs in feral toms. Methods: Feral toms were presented for castration at a local Humane Society during August-October 2014. Age was determined by records provided from feral cat colony managers and confirmed with dental eruption patterns. The age groups were: 2-2.5 months (weanling; n=6), 3-4 months (juvenile; n=6), 5-6 months (pubertal; n=6), and 12-24 months (adult; n=6). General anesthesia was induced and a routine open castration was performed. Both testicles from each cat were hemi-sectioned, formalin-fixed, paraffin-embedded, cut into sections (6 µm), and stained with hematoxylin and eosin. The slides were evaluated by a single observer (EB) blinded to age group using bright field microscopy (200X). Evidence of spermatogenesis was determined on the basis of presence of spermatozoa in the seminiferous tubule lumen. In addition, perpendicular diameters measured from 5 tubules for each testis were averaged and mean ± SD was determined for each age group. Tubular diameter was compared using a Student’s t test where p < 0.05 was defined as significant. The presence of spermatozoa in the lumen was compared using a Chi-square test. Results: Evidence of spermatogenesis in weanling, juvenile, pubertal, and adult toms was 0%, 17%, 67%, and 100%, respectively (p < 0.05 between successive age groups). The seminiferous tubular diameter was significantly larger in each successive age group (weanlings 88.10 ± 10.88 µm; juveniles 109.8 ± 8.89 µm; pubertal 142.2 ± 16.89 µm; adult 237.90 ± 52.45 µm). Discussion: Juvenile feral toms in the current study had significantly wider tubular diameter than previously reported for domestic toms under 5 months of age (86 µm), which supports our hypothesis that spermatogenesis is occurring at an earlier age in ferals. However, the time of year the previous measurements in domestics was not reported. If these measurements were made outside of the breeding season, this may explain why the tubular diameters were smaller. Future studies are planned to determine if folliculogenesis occurs earlier in queens as well. Close

• 59. [Article] Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices

  Alternating-current thin-film electroluminescent (ACTFEL) devices are metal-insulator-semiconductorinsulator- metal (MISIM) structures which emit light under high field, pulsed excitation. One aspect of ...

  Citation × Citation Citation Abstract Copy Title: Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices Author: Davidson, James D. (James Douglas), 1960- Alternating-current thin-film electroluminescent (ACTFEL) devices are metal-insulator-semiconductorinsulator- metal (MISIM) structures which emit light under high field, pulsed excitation. One aspect of ACTFEL operation that is not well understood is the aging of such devices with operating time. One of the primary goals of this thesis is to characterize the kinetics of ACTFEL aging and to determine the associated activation energy which is then used as an aid in identifying the physical mechanism responsible for aging. Toward this end a new method, the capacitance-voltage (C-V) technique, for electrical characterization of ACTFEL devices is developed and refined. The threshold voltage ,Vth, total capacitance Ctot, and the insulator capacitance, Cthg, as well as some information about the relative interface state density are available from C-V analysis. SPICE simulation and a discrete ACTFEL model are used to verify and refine the C-V technique. The heart of the SPICE model is the standard ACTFEL circuit model which consists of three capacitors representing the phosphor and two insulator layers and a pair of back-to-back Zener diodes which account for conduction in the phosphor above threshold. Model enhancements are the inclusion of five resistances which account for 1) the resistance of the transparent conducting layer, Rito, 2)and 3) the bulk insulator resistances, R1 and R2, 4) the phosphor layer bulk resistance, R, and 5) a diode resistance, Rd, which is in series with the back-to-back Zener diodes and is termed a hot electron resistor since it is associated with the emission of electrons from interface trap states. The refined SPICE equivalent circuit is found to give good agreement with experimental C-V curves and with C-V curves generated using a discrete ACTFEL model which is built using discrete capacitors and Zener diodes. Aging experiments are conducted using the C-V technique to monitor the threshold voltage as a function of aging time over a temperature range of -50 °C to 80 °C. An incubation period, in which the threshold voltage is constant, occurs for temperatures below 20 °C but no incubation period is observed for temperatures above 20 °C. After the incubation period, if any exists, the threshold voltage increases logarithmically with time to a saturated value which is temperature-dependent; logarithmic and saturated aging are collectively referred to as constituting short-term aging. Short-term aging is characterized by Ctot, C8, and phosphor threshold voltage which are independent of aging time, rigid shifts in the C-V transition to higher threshold voltages with aging time, and decreases in the conduction and polarization charges with aging time. A kinetic analysis of the variable-temperature ACTFEL aging characteristics results in an activation energy of 0.2 eV. Such experimental observations lead to a model for ACTFEL aging in which conduction electrons are trapped in deep level, fixed charge states which arise from atomic rearrangement at the interface. This trapped charge reduces the polarization charge with a corresponding increase in the threshold voltage. Title: Capacitance-voltage analysis, SPICE modeling, and aging studies of AC thin-film electroluminescent devices Author: Davidson, James D. (James Douglas), 1960- Alternating-current thin-film electroluminescent (ACTFEL) devices are metal-insulator-semiconductorinsulator- metal (MISIM) structures which emit light under high field, pulsed excitation. One aspect of ACTFEL operation that is not well understood is the aging of such devices with operating time. One of the primary goals of this thesis is to characterize the kinetics of ACTFEL aging and to determine the associated activation energy which is then used as an aid in identifying the physical mechanism responsible for aging. Toward this end a new method, the capacitance-voltage (C-V) technique, for electrical characterization of ACTFEL devices is developed and refined. The threshold voltage ,Vth, total capacitance Ctot, and the insulator capacitance, Cthg, as well as some information about the relative interface state density are available from C-V analysis. SPICE simulation and a discrete ACTFEL model are used to verify and refine the C-V technique. The heart of the SPICE model is the standard ACTFEL circuit model which consists of three capacitors representing the phosphor and two insulator layers and a pair of back-to-back Zener diodes which account for conduction in the phosphor above threshold. Model enhancements are the inclusion of five resistances which account for 1) the resistance of the transparent conducting layer, Rito, 2)and 3) the bulk insulator resistances, R1 and R2, 4) the phosphor layer bulk resistance, R, and 5) a diode resistance, Rd, which is in series with the back-to-back Zener diodes and is termed a hot electron resistor since it is associated with the emission of electrons from interface trap states. The refined SPICE equivalent circuit is found to give good agreement with experimental C-V curves and with C-V curves generated using a discrete ACTFEL model which is built using discrete capacitors and Zener diodes. Aging experiments are conducted using the C-V technique to monitor the threshold voltage as a function of aging time over a temperature range of -50 °C to 80 °C. An incubation period, in which the threshold voltage is constant, occurs for temperatures below 20 °C but no incubation period is observed for temperatures above 20 °C. After the incubation period, if any exists, the threshold voltage increases logarithmically with time to a saturated value which is temperature-dependent; logarithmic and saturated aging are collectively referred to as constituting short-term aging. Short-term aging is characterized by Ctot, C8, and phosphor threshold voltage which are independent of aging time, rigid shifts in the C-V transition to higher threshold voltages with aging time, and decreases in the conduction and polarization charges with aging time. A kinetic analysis of the variable-temperature ACTFEL aging characteristics results in an activation energy of 0.2 eV. Such experimental observations lead to a model for ACTFEL aging in which conduction electrons are trapped in deep level, fixed charge states which arise from atomic rearrangement at the interface. This trapped charge reduces the polarization charge with a corresponding increase in the threshold voltage. Close

• 60. [Article] Age-fecundity relationships in the striped seaperch Embiotoca lateralis from Yaquina Bay, Oregon

  A study was conducted at Yaquina Bay, Oregon, to determine the age-fecundity relationships in the striped seaperch Embiotoca lateralis. A questionnaire was sent to California, Oregon, and Washington to ...

  Citation × Citation Citation Abstract Copy Title: Age-fecundity relationships in the striped seaperch Embiotoca lateralis from Yaquina Bay, Oregon Author: Swedberg, Stephen Ernferd A study was conducted at Yaquina Bay, Oregon, to determine the age-fecundity relationships in the striped seaperch Embiotoca lateralis. A questionnaire was sent to California, Oregon, and Washington to ascertain what regulations were in effect, and the value of the family Embiotocidae with regard to the sport and commercial harvest. The questionnaire revealed that no state maintained a systematic account of each species landed, and further life history data appeared desirable for sport and commercial species. Fish were collected from March 20 to August 21, 1960, with 140 females and 26 males being collected for analysis by hook and line or 125-foot experimental gill net. Scales were imprinted on cellulose acetate cards or mounted between glass slides, The catch was measured in centimeters of standard length and weighed in grams. From 123 females, 2, 654 embryos were obtained, and a maximum of 22 embryos per female was measured in millimeters of standard length. The estimated time of annulus formation in most scales was from March 15 to June 12. Second and third annuli were primarily laid down in March and April, with the probable peak of annulus formation for females of ages IV, V and VI in May. Length-frequencies were presented by age-class and sex. Eighty-one females of age-class III dominated the sample. Females of age-classes II and III attained greater average lengths than males. In age-class II, average weights for females were slightly greater than those for males. Both sexes generally mature for the first time in their third year of life. Length-weight, and length-number of embryos per female, for females of age-classes III-IV, were expressed by the regression equation Y[subscript c] = a+ b (X). High correlations for length-weight were ob- tained. Additional females were needed to evaluate that age when weights would digress. Females of age-class V produced the most embryos per unit increase in length; this rate declined in age-class VI. The largest number of embryos produced by an age class was 1, 431, in age-class III. The average number (in parentheses) of embryos produced per female of each age class, was: II ( 17); III (18); IV (21); V (30); VI (31) and VII (32). The most prolific female was seven years old and contained 45 embryos. Sixteen diminutive embryos were collected in 10 out of 128 mature females. Most older females were thought to have ovulated earlier than younger females, for their embryos were generally larger than embryos of younger females. However, embryos from younger females could reach the approximate mean size of embryos of older females, but at a later date. Birth of embryos began about June 12 and ended in late July. Embryos averaged about 50 mm in standard length at birth. Suggestions are given for management of the striped seaperch. Title: Age-fecundity relationships in the striped seaperch Embiotoca lateralis from Yaquina Bay, Oregon Author: Swedberg, Stephen Ernferd A study was conducted at Yaquina Bay, Oregon, to determine the age-fecundity relationships in the striped seaperch Embiotoca lateralis. A questionnaire was sent to California, Oregon, and Washington to ascertain what regulations were in effect, and the value of the family Embiotocidae with regard to the sport and commercial harvest. The questionnaire revealed that no state maintained a systematic account of each species landed, and further life history data appeared desirable for sport and commercial species. Fish were collected from March 20 to August 21, 1960, with 140 females and 26 males being collected for analysis by hook and line or 125-foot experimental gill net. Scales were imprinted on cellulose acetate cards or mounted between glass slides, The catch was measured in centimeters of standard length and weighed in grams. From 123 females, 2, 654 embryos were obtained, and a maximum of 22 embryos per female was measured in millimeters of standard length. The estimated time of annulus formation in most scales was from March 15 to June 12. Second and third annuli were primarily laid down in March and April, with the probable peak of annulus formation for females of ages IV, V and VI in May. Length-frequencies were presented by age-class and sex. Eighty-one females of age-class III dominated the sample. Females of age-classes II and III attained greater average lengths than males. In age-class II, average weights for females were slightly greater than those for males. Both sexes generally mature for the first time in their third year of life. Length-weight, and length-number of embryos per female, for females of age-classes III-IV, were expressed by the regression equation Y[subscript c] = a+ b (X). High correlations for length-weight were ob- tained. Additional females were needed to evaluate that age when weights would digress. Females of age-class V produced the most embryos per unit increase in length; this rate declined in age-class VI. The largest number of embryos produced by an age class was 1, 431, in age-class III. The average number (in parentheses) of embryos produced per female of each age class, was: II ( 17); III (18); IV (21); V (30); VI (31) and VII (32). The most prolific female was seven years old and contained 45 embryos. Sixteen diminutive embryos were collected in 10 out of 128 mature females. Most older females were thought to have ovulated earlier than younger females, for their embryos were generally larger than embryos of younger females. However, embryos from younger females could reach the approximate mean size of embryos of older females, but at a later date. Birth of embryos began about June 12 and ended in late July. Embryos averaged about 50 mm in standard length at birth. Suggestions are given for management of the striped seaperch. Close

• 61. [Article] Interactive video communication technology and successful aging in place : applying the selective optimization with compensation model

  This study utilized the theoretical framework of selective optimization with compensation (SOC) (Baltes, 1987; Baltes & Baltes, 1990) to interpret older adults' definitions about successful aging in place. ...

  Citation × Citation Citation Abstract Copy Title: Interactive video communication technology and successful aging in place : applying the selective optimization with compensation model Author: Yamamoto, Toshiko This study utilized the theoretical framework of selective optimization with compensation (SOC) (Baltes, 1987; Baltes & Baltes, 1990) to interpret older adults' definitions about successful aging in place. Factors contributing to successful aging in place, including the importance of social interaction and perceptions of the usefulness of interactive video communication technology (IVC) for achieving optimal levels of social interaction and successful aging in place, were also determined. Data were collected using a questionnaire, home-observation checklist, seven-day social interaction diary, and in-depth interviews. The sample consisted of 14 women and four men who were over 75 years of age and living in their own homes. The participants were predominantly white, educated, mobile, and in good health. All participants declared that they would like to continue living in their own homes as long as possible. More than two-thirds had lived for over 30 years in their homes. Three major themes emerged from this study: successful aging in place, social interaction, and usefulness of IVC for aging in place. Participants' definitions of successful aging in place included factors related to health, mobility, independence, control, solitude, affordability, comfort, and social interactions. Social interactions represented, in the respondents' opinions, a major factor for successful aging in place. The participants had an active social life, employing a variety of social communication means, from face-to-face interactions and telephone to computers. Their social activities included club memberships, church activities, informal interactions with family members and friends, and formal interactions, especially with health care providers. The participants in this study did not perceive the IVC technology as important for their aging in place in their current situations. However, the participants admitted that the IVC could be a useful tool for people with limited health and mobility to allow them to maintain social interactions and successfully age in place. The interpretation of the findings is as follows: at their actual level of activity and mobility, the participants selected particular ways of communication and optimized these means. The IVC was perceived as a compensation mechanism to be used when other communication means fail due to health and mobility problems. Title: Interactive video communication technology and successful aging in place : applying the selective optimization with compensation model Author: Yamamoto, Toshiko This study utilized the theoretical framework of selective optimization with compensation (SOC) (Baltes, 1987; Baltes & Baltes, 1990) to interpret older adults' definitions about successful aging in place. Factors contributing to successful aging in place, including the importance of social interaction and perceptions of the usefulness of interactive video communication technology (IVC) for achieving optimal levels of social interaction and successful aging in place, were also determined. Data were collected using a questionnaire, home-observation checklist, seven-day social interaction diary, and in-depth interviews. The sample consisted of 14 women and four men who were over 75 years of age and living in their own homes. The participants were predominantly white, educated, mobile, and in good health. All participants declared that they would like to continue living in their own homes as long as possible. More than two-thirds had lived for over 30 years in their homes. Three major themes emerged from this study: successful aging in place, social interaction, and usefulness of IVC for aging in place. Participants' definitions of successful aging in place included factors related to health, mobility, independence, control, solitude, affordability, comfort, and social interactions. Social interactions represented, in the respondents' opinions, a major factor for successful aging in place. The participants had an active social life, employing a variety of social communication means, from face-to-face interactions and telephone to computers. Their social activities included club memberships, church activities, informal interactions with family members and friends, and formal interactions, especially with health care providers. The participants in this study did not perceive the IVC technology as important for their aging in place in their current situations. However, the participants admitted that the IVC could be a useful tool for people with limited health and mobility to allow them to maintain social interactions and successfully age in place. The interpretation of the findings is as follows: at their actual level of activity and mobility, the participants selected particular ways of communication and optimized these means. The IVC was perceived as a compensation mechanism to be used when other communication means fail due to health and mobility problems. Close

• 62. [Article] Endocrinology of sex-linked-recessive dwarf White Leghorn chickens, Gallus Domesticus, with special reference to the thyroid

  A comparison of the various endocrine glands, in addition to other anatomical measurements, was made on 19 normal and 21 dwarf 2-3-month-old females and 20 normal and 20 dwarf 7-13-month-old females of ...

  Citation × Citation Citation Abstract Copy Title: Endocrinology of sex-linked-recessive dwarf White Leghorn chickens, Gallus Domesticus, with special reference to the thyroid Author: Mirosh, Larry Wayne A comparison of the various endocrine glands, in addition to other anatomical measurements, was made on 19 normal and 21 dwarf 2-3-month-old females and 20 normal and 20 dwarf 7-13-month-old females of the White Leghorn breed. At both ages, dwarfs weighed significantly less and had significantly shorter shanks than normals. Comb weight and comb area (L X H) were significantly larger in normals than in dwarfs 7-13 months of age, but no significant difference was found in the 2-3 month age group. Ovaries in the 2-3 month age group were heavier in normals than in dwarfs, due to greater gonadotropin secretion in relation to body size. The divergent results in weight of the hypophyses on an absolute and a relative-to-body-weight basis may be attributed to the algebraic sum of synthesis storage and liberation of hormones by this gland. Also, absolute and relative weights of the adrenals did not always coincide in both age groups, which may be attributed to environmental factors influencing the release of ACTH from the hypophysis. The normals had significantly heavier thyroids than dwarfs. on an absolute and on a relative weight basis at both ages, which does not necessarily indicate a hyper- or hypothyroid condition in the latter group of birds. Normals secreted significantly more thyroxine than dwarfs at 7-13 months of age; whereas, no significant difference was found between these two types of chickens at 2-3 months of age, as determined by epithelial cell height. The significantly smaller colloid and follicle diameter found in thyroids of dwarfs than of normals may be attributed to the lower gland weights in the former group. Bioassay of the hypophyses from these chickens was conducted in immature, hypophysectomized, female rats. Dwarfs did not differ significantly from normals in STH activity, according to the tibia test, body weight gain and tail length. Greater epiphyseal plate responses were obtained from hypophyses of growing chickens. Thymus weight varied with dosage, which is attributed to several hormones acting on this gland. The normals had a significantly higher hypophyseal ACTH content than dwarfs 2-3 months of age, which is believed to be due to the hormone content of the hypophyses at the time of removal, rather than to dwarfism. Also, the younger birds were observed to have a higher ACTH content than older birds, which may be due to storage of this hormone in the hypophysis during the growing period. Dwarfs did not differ significantly from normals in gonadotropic activity at both ages, as evaluated by ovary, oviduct and uterus weight response in the assay rats. However, the older birds were observed to have higher gonadotropic activity than younger birds, as determined by ovary, oviduct and uterine weight and vaginal openings in the rats. No significant difference in FSH content of the hypophyses of dwarfs and normals of both ages was found, using ovarian follicle diameter. Observation of the interstitial cells in the rat ovaries revealed no difference between dwarfs and normals at both age classifications in ICSH content. No significant difference in TSH activity between dwarfs and normals within each age group was found, based on thyroid weight in the rats. Also, dwarfs did not appear to differ from normals of both ages in measurements on epithelial cell height and colloid and follicle diameter. Lack of appreciable differences between the treated rats and the controls in these measurements on the thyroids would indicate that rats did not respond to avian TSH. Title: Endocrinology of sex-linked-recessive dwarf White Leghorn chickens, Gallus Domesticus, with special reference to the thyroid Author: Mirosh, Larry Wayne A comparison of the various endocrine glands, in addition to other anatomical measurements, was made on 19 normal and 21 dwarf 2-3-month-old females and 20 normal and 20 dwarf 7-13-month-old females of the White Leghorn breed. At both ages, dwarfs weighed significantly less and had significantly shorter shanks than normals. Comb weight and comb area (L X H) were significantly larger in normals than in dwarfs 7-13 months of age, but no significant difference was found in the 2-3 month age group. Ovaries in the 2-3 month age group were heavier in normals than in dwarfs, due to greater gonadotropin secretion in relation to body size. The divergent results in weight of the hypophyses on an absolute and a relative-to-body-weight basis may be attributed to the algebraic sum of synthesis storage and liberation of hormones by this gland. Also, absolute and relative weights of the adrenals did not always coincide in both age groups, which may be attributed to environmental factors influencing the release of ACTH from the hypophysis. The normals had significantly heavier thyroids than dwarfs. on an absolute and on a relative weight basis at both ages, which does not necessarily indicate a hyper- or hypothyroid condition in the latter group of birds. Normals secreted significantly more thyroxine than dwarfs at 7-13 months of age; whereas, no significant difference was found between these two types of chickens at 2-3 months of age, as determined by epithelial cell height. The significantly smaller colloid and follicle diameter found in thyroids of dwarfs than of normals may be attributed to the lower gland weights in the former group. Bioassay of the hypophyses from these chickens was conducted in immature, hypophysectomized, female rats. Dwarfs did not differ significantly from normals in STH activity, according to the tibia test, body weight gain and tail length. Greater epiphyseal plate responses were obtained from hypophyses of growing chickens. Thymus weight varied with dosage, which is attributed to several hormones acting on this gland. The normals had a significantly higher hypophyseal ACTH content than dwarfs 2-3 months of age, which is believed to be due to the hormone content of the hypophyses at the time of removal, rather than to dwarfism. Also, the younger birds were observed to have a higher ACTH content than older birds, which may be due to storage of this hormone in the hypophysis during the growing period. Dwarfs did not differ significantly from normals in gonadotropic activity at both ages, as evaluated by ovary, oviduct and uterus weight response in the assay rats. However, the older birds were observed to have higher gonadotropic activity than younger birds, as determined by ovary, oviduct and uterine weight and vaginal openings in the rats. No significant difference in FSH content of the hypophyses of dwarfs and normals of both ages was found, using ovarian follicle diameter. Observation of the interstitial cells in the rat ovaries revealed no difference between dwarfs and normals at both age classifications in ICSH content. No significant difference in TSH activity between dwarfs and normals within each age group was found, based on thyroid weight in the rats. Also, dwarfs did not appear to differ from normals of both ages in measurements on epithelial cell height and colloid and follicle diameter. Lack of appreciable differences between the treated rats and the controls in these measurements on the thyroids would indicate that rats did not respond to avian TSH. Close

• 63. [Article] The use of time by homemakers with children

  The purpose of the study was to find out how a group of faculty wives with children used their time and to investigate some factors in housing and equipment which might influence how they used their time. ...

  Citation × Citation Citation Abstract Copy Title: The use of time by homemakers with children Author: Meyer, Bonnie Martin The purpose of the study was to find out how a group of faculty wives with children used their time and to investigate some factors in housing and equipment which might influence how they used their time. A comparison was made between homemakers with two pre-school age children and homemakers with two school age children in the way they used their time. Following a letter of explanation of the study, the writer contacted the homemakers by phone to make an appointment to visit them. During this visit the writer obtained the information for the questionnaire and explained the time sheets. Twenty-four homemakers, 12 with pre-school children, and 12 with school-age children kept usable records for this study. The homemakers ranged in age from 21 to 62 years of age. All of the homemakers had attended college with 42 percent graduating and an additional 16.5 percent earning their master's degree. Two were registered nurses. Both groups averaged four years of work before marriage. The homemakers with pre-school children had been married an average of eight years while the homemakers with school age children had been married an average of 18 years. The children ranged in age from four months to 18 years old. The 12.5 percent of the families that did not own their own homes were all from the group with pre-school children. Although all of the homes were well equipped, the families that had been established the longest time had slightly more equipment. Half of the total group used time plans; the majority of the homemakers using time plans were homemakers with pre-school children. Homemakers in this study as well as previous studies most often listed food preparation as the homemaking activity they most enjoyed. Again, cleaning house was most often listed as the activity least enjoyed, followed by ironing. Improved housing, equipment, and methods have failed to change these attitudes in over a quarter of a century. The homemakers with pre-school children spent the greatest percentage of their time caring for children followed by meal preparation and clean-up; the homemakers with school age children spent the greatest percentage of their time on food preparation and clean-up. Both groups spent a little over two and a half hours on meal preparation and clean-up. Homemakers with school age children averaged 48 minutes a day on laundry, whereas homemakers with pre-school children averaged 70 minutes a day. Cleaning house averaged 63 minutes a day for homemakers with school age children and 45 minutes a day for homemakers with pre-school children. Homemakers with school age children averaged 39 minutes for shopping, whereas homemakers with pre-school children averaged 23 minutes. The homemakers with school age children averaged 8 hours and 45 minutes of rest per day, whereas the homemakers with pre-school children averaged 8 hours and 8 minutes. Homemakers with school age children spent more time eating meals, on personal care, and on entertaining and social activities, whereas homemakers with pre-school children derived much of their leisure time from unplanned coffee breaks and chatting with neighbors. Other than the great difference in the amount of time the two groups spent in caring for their children, (the homemakers with pre-school children spent 3 hours and 38 minutes while the homemakers with school age children spent 39 minutes), there was great similarity in the way the two groups used their time. Another finding is that there is little difference in the amount of time the homemaker spent on different homemaking activities at the time of this study in comparison to studies done during the past quarter of a century. Title: The use of time by homemakers with children Author: Meyer, Bonnie Martin The purpose of the study was to find out how a group of faculty wives with children used their time and to investigate some factors in housing and equipment which might influence how they used their time. A comparison was made between homemakers with two pre-school age children and homemakers with two school age children in the way they used their time. Following a letter of explanation of the study, the writer contacted the homemakers by phone to make an appointment to visit them. During this visit the writer obtained the information for the questionnaire and explained the time sheets. Twenty-four homemakers, 12 with pre-school children, and 12 with school-age children kept usable records for this study. The homemakers ranged in age from 21 to 62 years of age. All of the homemakers had attended college with 42 percent graduating and an additional 16.5 percent earning their master's degree. Two were registered nurses. Both groups averaged four years of work before marriage. The homemakers with pre-school children had been married an average of eight years while the homemakers with school age children had been married an average of 18 years. The children ranged in age from four months to 18 years old. The 12.5 percent of the families that did not own their own homes were all from the group with pre-school children. Although all of the homes were well equipped, the families that had been established the longest time had slightly more equipment. Half of the total group used time plans; the majority of the homemakers using time plans were homemakers with pre-school children. Homemakers in this study as well as previous studies most often listed food preparation as the homemaking activity they most enjoyed. Again, cleaning house was most often listed as the activity least enjoyed, followed by ironing. Improved housing, equipment, and methods have failed to change these attitudes in over a quarter of a century. The homemakers with pre-school children spent the greatest percentage of their time caring for children followed by meal preparation and clean-up; the homemakers with school age children spent the greatest percentage of their time on food preparation and clean-up. Both groups spent a little over two and a half hours on meal preparation and clean-up. Homemakers with school age children averaged 48 minutes a day on laundry, whereas homemakers with pre-school children averaged 70 minutes a day. Cleaning house averaged 63 minutes a day for homemakers with school age children and 45 minutes a day for homemakers with pre-school children. Homemakers with school age children averaged 39 minutes for shopping, whereas homemakers with pre-school children averaged 23 minutes. The homemakers with school age children averaged 8 hours and 45 minutes of rest per day, whereas the homemakers with pre-school children averaged 8 hours and 8 minutes. Homemakers with school age children spent more time eating meals, on personal care, and on entertaining and social activities, whereas homemakers with pre-school children derived much of their leisure time from unplanned coffee breaks and chatting with neighbors. Other than the great difference in the amount of time the two groups spent in caring for their children, (the homemakers with pre-school children spent 3 hours and 38 minutes while the homemakers with school age children spent 39 minutes), there was great similarity in the way the two groups used their time. Another finding is that there is little difference in the amount of time the homemaker spent on different homemaking activities at the time of this study in comparison to studies done during the past quarter of a century. Close

• 64. [Article] New 40Ar/39Ar age progression for the Louisville hot spot trail and implications for inter–hot spot motion

  In this study we present 42 new ⁴⁰Ar/³⁹Ar incremental heating age determinations that contribute to an updated age progression for the Louisville seamount trail. Louisville is the South Pacific counterpart ...

  Citation × Citation Citation Abstract Copy Title: New 40Ar/39Ar age progression for the Louisville hot spot trail and implications for inter–hot spot motion Author: Gee, Jeffrey S., Lonsdale, Peter F., Colwell, Lauren E., Koppers, Anthony A. P., Mahoney, John J., Duncan, Robert A., Gowen, Molly D. In this study we present 42 new ⁴⁰Ar/³⁹Ar incremental heating age determinations that contribute to an updated age progression for the Louisville seamount trail. Louisville is the South Pacific counterpart to the Hawaiian‐Emperor seamount trail, both trails representing intraplate volcanism over the same time interval (~80 Ma to present) and being examples of primary hot spot lineaments. Our data provide evidence for an age‐progressive trend from 71 to 21 Ma. Assuming fixed hot spots, this makes possible a direct comparison to the Hawaiian‐Emperor age progression and the most recent absolute plate motion (APM) model (WK08G) of Wessel and Kroenke (2008). We observe that for the Louisville seamount trail the measured ages are systematically older relative to both the WK08G model predictions and Hawaiian seamount ages, with offsets ranging up to 6 Myr. Taking into account the uncertainty about the duration of eruption and magmatic succession at individual Louisville volcanoes, these age offsets should be considered minimum estimates, as our sampling probably tended to recover the youngest lava flows. These large deviations point to either a contribution of inter–hot spot motion between the Louisville and Hawaiian hot spots or to a more easterly location of the Louisville hot spot than the one inferred in the WK08G model. Both scenarios are investigated in this paper, whereby the more eastern hot spot location (52.0°S, 134.5°W versus 52.4°S, 137.2°W) reduces the average age offset, but still results in a relatively large maximum offset of 3.7 Myr. When comparing the new ages to the APM models (S04P, S04G) by Steinberger et al. (2004) that attempt to compensate for the motion of hot spots in the Pacific (Hawaii) or globally (Hawaii, Louisville, Reunion and Walvis), the measured and predicted ages are more in agreement, showing only a maximum offset of 2.3 Myr with respect to the S04G model. At face value these more advanced APM models, which consider both plate and hot spot motions, therefore provide a better fit to the new Louisville age data. The fit is particularly good for seamounts younger than 50 Ma, a period for which there is little predicted motion for the Louisville hot spot and little inter–hot spot motion with Hawaii. However, discrepancies in the Louisville age‐distance record prior to 50 Ma indicate there is an extra source of inter–hot spot motion between Louisville and the other Pacific hot spots that was not corrected for in the global S04G model. Finally, based on six new ⁴⁰Ar/³⁹Ar age dates, the 169°W bend in the Louisville seamount trail seems to have formed at least 3 Myr before the formation of the Hawaiian‐Emperor bend. The timing of the most acute parts of both bends thus appears to be asynchronous, which would require other processes (e.g., plume motions) than a global plate motion change between 50 and 47 Ma to explain these two observations. Title: New 40Ar/39Ar age progression for the Louisville hot spot trail and implications for inter–hot spot motion Author: Gee, Jeffrey S., Lonsdale, Peter F., Colwell, Lauren E., Koppers, Anthony A. P., Mahoney, John J., Duncan, Robert A., Gowen, Molly D. In this study we present 42 new ⁴⁰Ar/³⁹Ar incremental heating age determinations that contribute to an updated age progression for the Louisville seamount trail. Louisville is the South Pacific counterpart to the Hawaiian‐Emperor seamount trail, both trails representing intraplate volcanism over the same time interval (~80 Ma to present) and being examples of primary hot spot lineaments. Our data provide evidence for an age‐progressive trend from 71 to 21 Ma. Assuming fixed hot spots, this makes possible a direct comparison to the Hawaiian‐Emperor age progression and the most recent absolute plate motion (APM) model (WK08G) of Wessel and Kroenke (2008). We observe that for the Louisville seamount trail the measured ages are systematically older relative to both the WK08G model predictions and Hawaiian seamount ages, with offsets ranging up to 6 Myr. Taking into account the uncertainty about the duration of eruption and magmatic succession at individual Louisville volcanoes, these age offsets should be considered minimum estimates, as our sampling probably tended to recover the youngest lava flows. These large deviations point to either a contribution of inter–hot spot motion between the Louisville and Hawaiian hot spots or to a more easterly location of the Louisville hot spot than the one inferred in the WK08G model. Both scenarios are investigated in this paper, whereby the more eastern hot spot location (52.0°S, 134.5°W versus 52.4°S, 137.2°W) reduces the average age offset, but still results in a relatively large maximum offset of 3.7 Myr. When comparing the new ages to the APM models (S04P, S04G) by Steinberger et al. (2004) that attempt to compensate for the motion of hot spots in the Pacific (Hawaii) or globally (Hawaii, Louisville, Reunion and Walvis), the measured and predicted ages are more in agreement, showing only a maximum offset of 2.3 Myr with respect to the S04G model. At face value these more advanced APM models, which consider both plate and hot spot motions, therefore provide a better fit to the new Louisville age data. The fit is particularly good for seamounts younger than 50 Ma, a period for which there is little predicted motion for the Louisville hot spot and little inter–hot spot motion with Hawaii. However, discrepancies in the Louisville age‐distance record prior to 50 Ma indicate there is an extra source of inter–hot spot motion between Louisville and the other Pacific hot spots that was not corrected for in the global S04G model. Finally, based on six new ⁴⁰Ar/³⁹Ar age dates, the 169°W bend in the Louisville seamount trail seems to have formed at least 3 Myr before the formation of the Hawaiian‐Emperor bend. The timing of the most acute parts of both bends thus appears to be asynchronous, which would require other processes (e.g., plume motions) than a global plate motion change between 50 and 47 Ma to explain these two observations. Close

• 65. [Article] A role for ceramide accumulation in age-related cardiac mitochondrial dysfunction

  Ceramides are a group of lipids in the sphingolipid family that are potent cell signaling molecules. Elevations in ceramide levels above the norm generally lead to apoptosis. Evidence from in vitro studies ...

  Citation × Citation Citation Abstract Copy Title: A role for ceramide accumulation in age-related cardiac mitochondrial dysfunction Author: Monette, Jeffrey S. Ceramides are a group of lipids in the sphingolipid family that are potent cell signaling molecules. Elevations in ceramide levels above the norm generally lead to apoptosis. Evidence from in vitro studies suggests that accumulation of ceramides within mitochondria leads to dysfunction of the mitochondria. This includes inhibition of the electron transport chain and release of reactive oxygen species (ROS). Large elevations of mitochondrial ceramide may also lead to death of the cell as they promote membrane permeability transition, which allows the release of cytochrome c and other apoptogenic factors. With age, cardiac mitochondria show a similar dysfunctional phenotype to that found in conditions of acute ceramide elevation. We therefore hypothesize that ceramides may be accumulating in cardiac mitochondria from aged animals. To elucidate the characteristics of the sphingolipidome, we developed both mitochondrial isolation techniques and tandem mass spectrometry assays to specifically and sensitively monitor mitochondrial sphingolipids. Using these techniques, it was found that mitochondria contain six distinct ceramide species with highly saturated lipid moieties. Using young (3-6 months old; which corresponds to a post-adolescent human) and old (24 to 28 months old; which corresponds to an elderly human) Fischer 344 rat hearts, we found that aging leads to a significant increase in total mitochondrial ceramides (32%, p < 0.03), with C₁₆-, C₁₈-, and C₂₄:₁-ceramides showing the largest percent increases (72.3%, 73.4%, and 77.7%, respectively, p < 0.05). Furthermore, the age-associated elevation in ceramide levels correlated to a 28% decrease in the activity of complex IV of the electron transport chain (p < 0.05), which could be replicated in vitro by inducing a ceramide accumulation in mitochondria isolated from young animals. Mitochondria do not contain enzymes for de novo ceramide biosynthesis, rather, these organelles have sphingomyelinases, a family of enzymes that cleave the phosphorylcholine headgroup from nascent pools of sphingomyelin. Specifically, mitochondria contain the magnesium-requiring isoform of sphingomyelinase with a neutral pH optima (nSMase). Recent work has shown that nSMase activity is inversely regulated by glutathione status. Because cardiac mitochondrial glutathione (mGSH) declines by up to 60% with age, we hypothesized that the loss in mGSH leads to an increase in ceramides through the upregulation of nSMase. To determine whether loss of mGSH plays a role in the regulation of mitochondrial nSMase activity, mGSH levels were depleted by treating freshly isolated hepatocytes with 3-hydroxy-4-pentenoate (3HP). It was found that 3HP rapidly depleted mGSH in a concentration-dependent manner (EC₅₀ = 232 μM, p < 0.05). Moreover, this depletion led to an increase in nSMase activity (24 ± 3% at 250 μM 3HP, p < 0.05), and an increase in total ceramide levels (27%, p < 0.05). These findings suggest that mGSH status plays a critical role in the maintenance of ceramide levels within mitochondria. Furthermore, because nSMase activity is regulated by mGSH levels, we hypothesized that any agent promoting an increase in mGSH would reverse the ceramide accumulation seen in cardiac mitochondria from aged animals. Lipoic acid (LA) is a naturally occurring dithiol compound used for many years as an anti-inflammatory agent. LA-supplementation has been shown to increase cellular and mGSH by increasing cellular cysteine levels in the aging heart. In order to determine whether LA reverses the age-associated ceramidosis in cardiac mitochondria, young and old F344 rats were pair-fed LA [0.2% (w/w) in the diet] against controls for two weeks and cardiac mitochondria were subsequently isolated and analyzed. It was found that LA-treatment reversed the age-associated decline in mGSH levels [decreased 43% with age (p < 0.05)], and reduced nSMase activity [increased 103% with age (p < 0.05)]. Ceramide levels were reduced [elevated 32% with age (p < 0.03)] so that they were no longer different from young controls and complex IV activity restored t youthful levels [declined 28% with age (p < 0.05)]. In conclusion, this dissertation provides evidence to support a new mechanism that explains, at least in part, the progression of mitochondrial dysfunction in the aging heart, and may also contribute to understanding the age-related loss of cardiomyocytes. It also provides mechanistic insights into the overall health benefits of LA supplementation and supports its use as a safe, natural, and "age-essential" micronutrient. Title: A role for ceramide accumulation in age-related cardiac mitochondrial dysfunction Author: Monette, Jeffrey S. Ceramides are a group of lipids in the sphingolipid family that are potent cell signaling molecules. Elevations in ceramide levels above the norm generally lead to apoptosis. Evidence from in vitro studies suggests that accumulation of ceramides within mitochondria leads to dysfunction of the mitochondria. This includes inhibition of the electron transport chain and release of reactive oxygen species (ROS). Large elevations of mitochondrial ceramide may also lead to death of the cell as they promote membrane permeability transition, which allows the release of cytochrome c and other apoptogenic factors. With age, cardiac mitochondria show a similar dysfunctional phenotype to that found in conditions of acute ceramide elevation. We therefore hypothesize that ceramides may be accumulating in cardiac mitochondria from aged animals. To elucidate the characteristics of the sphingolipidome, we developed both mitochondrial isolation techniques and tandem mass spectrometry assays to specifically and sensitively monitor mitochondrial sphingolipids. Using these techniques, it was found that mitochondria contain six distinct ceramide species with highly saturated lipid moieties. Using young (3-6 months old; which corresponds to a post-adolescent human) and old (24 to 28 months old; which corresponds to an elderly human) Fischer 344 rat hearts, we found that aging leads to a significant increase in total mitochondrial ceramides (32%, p < 0.03), with C₁₆-, C₁₈-, and C₂₄:₁-ceramides showing the largest percent increases (72.3%, 73.4%, and 77.7%, respectively, p < 0.05). Furthermore, the age-associated elevation in ceramide levels correlated to a 28% decrease in the activity of complex IV of the electron transport chain (p < 0.05), which could be replicated in vitro by inducing a ceramide accumulation in mitochondria isolated from young animals. Mitochondria do not contain enzymes for de novo ceramide biosynthesis, rather, these organelles have sphingomyelinases, a family of enzymes that cleave the phosphorylcholine headgroup from nascent pools of sphingomyelin. Specifically, mitochondria contain the magnesium-requiring isoform of sphingomyelinase with a neutral pH optima (nSMase). Recent work has shown that nSMase activity is inversely regulated by glutathione status. Because cardiac mitochondrial glutathione (mGSH) declines by up to 60% with age, we hypothesized that the loss in mGSH leads to an increase in ceramides through the upregulation of nSMase. To determine whether loss of mGSH plays a role in the regulation of mitochondrial nSMase activity, mGSH levels were depleted by treating freshly isolated hepatocytes with 3-hydroxy-4-pentenoate (3HP). It was found that 3HP rapidly depleted mGSH in a concentration-dependent manner (EC₅₀ = 232 μM, p < 0.05). Moreover, this depletion led to an increase in nSMase activity (24 ± 3% at 250 μM 3HP, p < 0.05), and an increase in total ceramide levels (27%, p < 0.05). These findings suggest that mGSH status plays a critical role in the maintenance of ceramide levels within mitochondria. Furthermore, because nSMase activity is regulated by mGSH levels, we hypothesized that any agent promoting an increase in mGSH would reverse the ceramide accumulation seen in cardiac mitochondria from aged animals. Lipoic acid (LA) is a naturally occurring dithiol compound used for many years as an anti-inflammatory agent. LA-supplementation has been shown to increase cellular and mGSH by increasing cellular cysteine levels in the aging heart. In order to determine whether LA reverses the age-associated ceramidosis in cardiac mitochondria, young and old F344 rats were pair-fed LA [0.2% (w/w) in the diet] against controls for two weeks and cardiac mitochondria were subsequently isolated and analyzed. It was found that LA-treatment reversed the age-associated decline in mGSH levels [decreased 43% with age (p < 0.05)], and reduced nSMase activity [increased 103% with age (p < 0.05)]. Ceramide levels were reduced [elevated 32% with age (p < 0.03)] so that they were no longer different from young controls and complex IV activity restored t youthful levels [declined 28% with age (p < 0.05)]. In conclusion, this dissertation provides evidence to support a new mechanism that explains, at least in part, the progression of mitochondrial dysfunction in the aging heart, and may also contribute to understanding the age-related loss of cardiomyocytes. It also provides mechanistic insights into the overall health benefits of LA supplementation and supports its use as a safe, natural, and "age-essential" micronutrient. Close

• 66. [Article] Accelerated food source location in aging Drosophila

  Adequate energy stores are essential for animal survival, and sophisticated neuroendocrine mechanisms evolved to stimulate foraging in response to nutrient deprivation. Food search behavior is usually ...

  Citation × Citation Citation Abstract Copy Title: Accelerated food source location in aging Drosophila Author: Egenriether, Sada Adequate energy stores are essential for animal survival, and sophisticated neuroendocrine mechanisms evolved to stimulate foraging in response to nutrient deprivation. Food search behavior is usually investigated in young animals, and it is not known how aging alters this behavior. To address this question in Drosophila, we compared the ability to locate food by olfaction in young and old flies using a food-filled trap. As aging is associated with decline in motor functions, learning, and memory, we expected that aged flies would take longer to enter the food trap than their young counterparts. Surprisingly, old flies located food with significantly shorter latency than the young ones. We determined that old flies have significantly lower fat reserves and are more susceptible to starvation than young flies. Food search latency was shortened in young wild type flies that were starved until their fat was depleted. We also determined that the difference in food finding latency (FFL) between young and old flies is mediated by insulin signaling. Together, our data suggest that shorter FFL in old flies is linked to age-dependent differences in metabolic status. Title: Accelerated food source location in aging Drosophila Author: Egenriether, Sada Adequate energy stores are essential for animal survival, and sophisticated neuroendocrine mechanisms evolved to stimulate foraging in response to nutrient deprivation. Food search behavior is usually investigated in young animals, and it is not known how aging alters this behavior. To address this question in Drosophila, we compared the ability to locate food by olfaction in young and old flies using a food-filled trap. As aging is associated with decline in motor functions, learning, and memory, we expected that aged flies would take longer to enter the food trap than their young counterparts. Surprisingly, old flies located food with significantly shorter latency than the young ones. We determined that old flies have significantly lower fat reserves and are more susceptible to starvation than young flies. Food search latency was shortened in young wild type flies that were starved until their fat was depleted. We also determined that the difference in food finding latency (FFL) between young and old flies is mediated by insulin signaling. Together, our data suggest that shorter FFL in old flies is linked to age-dependent differences in metabolic status. Close

• 67. [Article] Investigating the age-related loss of endoplasmic reticulum stress response

  The endoplasmic reticulum (ER) is a crucial organelle in the cell where protein folding and processing occurs, and conditions that negatively affect ER functions are highly detrimental to the cell. The ...

  Citation × Citation Citation Abstract Copy Title: Investigating the age-related loss of endoplasmic reticulum stress response Author: Fallahi, Anahita The endoplasmic reticulum (ER) is a crucial organelle in the cell where protein folding and processing occurs, and conditions that negatively affect ER functions are highly detrimental to the cell. The accumulation of unfolded/misfolded proteins in the ER leads to a condition known as ER Stress. The ER has developed various pro-survival and pro-apoptosis signaling pathways that attempt to cope with this stress. ER stress is relevant to many clinical studies and has been linked to a variety of age-related diseases, including Huntington’s, Alzheimer’s, Parkinson’s and heart disease. Despite these findings, the manner in which ER stress response is altered with age hasn’t been thoroughly studied and constitutes a gap in knowledge. In this study, we investigated the age-related loss of ER stress response in young and old rats. Our results suggest that, in both young and old cells, the pro-apoptosis pathway which utilizes the transcription factor, CHOP, remains intact with age. However, the pro-survival pathway acting through PERK/Nrf2 and the phase II detoxification enzyme NQO1 show elevated activity in the young cells, but a loss of function in the old. These results suggest that stresses which would not cause cell death in young individuals may induce cell death in the elderly. Title: Investigating the age-related loss of endoplasmic reticulum stress response Author: Fallahi, Anahita The endoplasmic reticulum (ER) is a crucial organelle in the cell where protein folding and processing occurs, and conditions that negatively affect ER functions are highly detrimental to the cell. The accumulation of unfolded/misfolded proteins in the ER leads to a condition known as ER Stress. The ER has developed various pro-survival and pro-apoptosis signaling pathways that attempt to cope with this stress. ER stress is relevant to many clinical studies and has been linked to a variety of age-related diseases, including Huntington’s, Alzheimer’s, Parkinson’s and heart disease. Despite these findings, the manner in which ER stress response is altered with age hasn’t been thoroughly studied and constitutes a gap in knowledge. In this study, we investigated the age-related loss of ER stress response in young and old rats. Our results suggest that, in both young and old cells, the pro-apoptosis pathway which utilizes the transcription factor, CHOP, remains intact with age. However, the pro-survival pathway acting through PERK/Nrf2 and the phase II detoxification enzyme NQO1 show elevated activity in the young cells, but a loss of function in the old. These results suggest that stresses which would not cause cell death in young individuals may induce cell death in the elderly. Close

• 68. [Article] Perceptions of residential grab bars among community dwelling seniors

  Despite the perceived importance of grab bars to facilitate aging-in-place and healthy aging, many community-dwelling older adults do not have them installed. The aim of this study was to investigate predictors ...

  Citation × Citation Citation Abstract Copy Title: Perceptions of residential grab bars among community dwelling seniors Author: Thrall, Patti L. Despite the perceived importance of grab bars to facilitate aging-in-place and healthy aging, many community-dwelling older adults do not have them installed. The aim of this study was to investigate predictors of grab bar installation among well-educated community dwelling seniors. Data was collected quantitatively through an electronic survey of Oregon residents 50 years of age and older. The research analysis was completed using logistic regression with SPSS and qualitative analysis for the open questions. Title: Perceptions of residential grab bars among community dwelling seniors Author: Thrall, Patti L. Despite the perceived importance of grab bars to facilitate aging-in-place and healthy aging, many community-dwelling older adults do not have them installed. The aim of this study was to investigate predictors of grab bar installation among well-educated community dwelling seniors. Data was collected quantitatively through an electronic survey of Oregon residents 50 years of age and older. The research analysis was completed using logistic regression with SPSS and qualitative analysis for the open questions. Close

• 69. [Article] Sediment reservoir dynamics on steepland valley floors : influence of network structure and effects of inherited ages

  Sediment deposit ages inferred from radiocarbon dating of stream bank material were used to estimate residence times of valley-floor deposits in headwater valleys of the Oregon Coast Range, USA. Inherited ...

  Citation × Citation Citation Abstract Copy Title: Sediment reservoir dynamics on steepland valley floors : influence of network structure and effects of inherited ages Author: Frueh, Walter Terry Sediment deposit ages inferred from radiocarbon dating of stream bank material were used to estimate residence times of valley-floor deposits in headwater valleys of the Oregon Coast Range, USA. Inherited ages of radiocarbon-dated material, i.e., time between carbon fixation in wood and its incorporation in a sediment deposit, can result in over-estimation of the ages of those deposits and, hence, the residence times of sediment within those units. Calibrated radiocarbon dates of 126 charcoal pieces sampled from Knowles Creek were used to estimate the distribution of inherited ages in fourteen depositional units representing three deposit types: fluvial fines, fluvial gravels, and debris flows. Within a depositional unit, the inherited age distribution of a piece of charcoal was estimated by convolving its calibrated age distribution with that of the piece of charcoal with the smallest weighted-mean calibrated age (i.e., an approximation of a unit's date of deposition) within that unit. All inherited age distributions for a particular deposit type were then added and normalized to provide a probability distribution of inherited ages for that deposit type. Probability distributions of inherited ages average 688, 1506, and 666 yr for fluvial fines, fluvial gravels, and debris flow units, respectively. Curves were fit to inherited age distributions for each deposit type. These curve fits were then convolved with deposit age distributions (i.e., equal to calibrated age distributions of woody material sampled from stream banks) of samples from Bear Creek (Lancaster and Casebeer, 2007) to correct these deposit ages for inherited age. This convolution gives a corrected deposit age. In cases in which means of corrected deposit age distributions for an upper unit were older than those of a lower unit within a stratigraphic column, the upper sample’s corrected deposit age distribution was set to that of the youngest lower in the stratigraphic section. Convolution shifted individual deposit age distributions towards zero and increased their standard deviation by an average of 365%. However, convolution decreased the standard deviations of normalized probability distribution functions of deposit ages inferred from many samples from 1340 to 1197 yr, and from 471 to 416 yr for lower and upper reaches, respectively, of the Bear Creek valley in the Oregon Coast Range. Convolution decreased estimates of mean deposit ages from 1296 to 1051 yr, and from 308 to 245 yr for lower and upper reaches, respectively, of the Bear Creek. Estimates of percentages of basin denudation passing through each reach's deposit ("trapping efficiency") increased from 11.6% to 14.4%, and from 25.4% to 31.9% for lower and upper Bear Creek, respectively. However, basic shapes of residence time distributions and, thus, inferences regarding removal of sediment from the reaches did not change after deposit dates were corrected. Sediment residence times in the lower Bear Creek valley are exponentially distributed, which implies that all sediment has a uniform probability of evacuation from deposits, whereas the power-law-distributed residence times in upper Bear imply preferential evacuation of younger deposits and preservation of older deposits. Much of the sediment transported onto valley floors via debris flows is deposited, and then is evacuated over longer times. Volumes and residence times of stored sediment in these deposits at the transition from debris flow to fluvial evacuation, and their associated width of valley floors, vary throughout a network. Export volumes and frequencies from tributaries are controls on deposit volumes and may control valley widening of mainstem valley floors. In addition, closely spaced tributaries may exert composite effects on valley floor landforms. It is hypothesized that the volumes of sediment stored at confluences increases with contributing watershed area of tributaries to the point where tributary slopes are low enough to cause most debris flows to be deposited within tributary valleys instead of in the mainstem valley. In four ~1 km reaches with contributing watershed areas of 0.3 to 5.0 km², field surveys provided measures of width of valley floors and volume of deposits, and radiocarbon dating of charcoal provided residence times of sediment in these deposits. Mean residence times of reaches vary between 1.1 and 2.5 kyr. Exponential distributions fit to residence times within two of the reaches imply evacuation of sediment independent of deposit ages. Power-law fits to residence times of the other two reaches imply age-dependent evacuation of deposits. Distribution shapes of residence times, and their means, do not vary systematically with contributing watershed area of mainstems. Mean width of mainstem valley floors increases with contributing watershed areas of both mainstems and their respective tributaries. Volumes of sediment stored on the valley floor increase with contributing areas of mainstems, and these volumes at tributary junctions peaked at tributary contributing areas of ~0.1 km². Percentage of basin denudation entering storage decreases with contributing area of mainstem. This decrease may be due to increasing percentages of sediment supply via fluvial transport for larger watersheds, and much, if not most, of this supply routes through the system quickly. Title: Sediment reservoir dynamics on steepland valley floors : influence of network structure and effects of inherited ages Author: Frueh, Walter Terry Sediment deposit ages inferred from radiocarbon dating of stream bank material were used to estimate residence times of valley-floor deposits in headwater valleys of the Oregon Coast Range, USA. Inherited ages of radiocarbon-dated material, i.e., time between carbon fixation in wood and its incorporation in a sediment deposit, can result in over-estimation of the ages of those deposits and, hence, the residence times of sediment within those units. Calibrated radiocarbon dates of 126 charcoal pieces sampled from Knowles Creek were used to estimate the distribution of inherited ages in fourteen depositional units representing three deposit types: fluvial fines, fluvial gravels, and debris flows. Within a depositional unit, the inherited age distribution of a piece of charcoal was estimated by convolving its calibrated age distribution with that of the piece of charcoal with the smallest weighted-mean calibrated age (i.e., an approximation of a unit's date of deposition) within that unit. All inherited age distributions for a particular deposit type were then added and normalized to provide a probability distribution of inherited ages for that deposit type. Probability distributions of inherited ages average 688, 1506, and 666 yr for fluvial fines, fluvial gravels, and debris flow units, respectively. Curves were fit to inherited age distributions for each deposit type. These curve fits were then convolved with deposit age distributions (i.e., equal to calibrated age distributions of woody material sampled from stream banks) of samples from Bear Creek (Lancaster and Casebeer, 2007) to correct these deposit ages for inherited age. This convolution gives a corrected deposit age. In cases in which means of corrected deposit age distributions for an upper unit were older than those of a lower unit within a stratigraphic column, the upper sample’s corrected deposit age distribution was set to that of the youngest lower in the stratigraphic section. Convolution shifted individual deposit age distributions towards zero and increased their standard deviation by an average of 365%. However, convolution decreased the standard deviations of normalized probability distribution functions of deposit ages inferred from many samples from 1340 to 1197 yr, and from 471 to 416 yr for lower and upper reaches, respectively, of the Bear Creek valley in the Oregon Coast Range. Convolution decreased estimates of mean deposit ages from 1296 to 1051 yr, and from 308 to 245 yr for lower and upper reaches, respectively, of the Bear Creek. Estimates of percentages of basin denudation passing through each reach's deposit ("trapping efficiency") increased from 11.6% to 14.4%, and from 25.4% to 31.9% for lower and upper Bear Creek, respectively. However, basic shapes of residence time distributions and, thus, inferences regarding removal of sediment from the reaches did not change after deposit dates were corrected. Sediment residence times in the lower Bear Creek valley are exponentially distributed, which implies that all sediment has a uniform probability of evacuation from deposits, whereas the power-law-distributed residence times in upper Bear imply preferential evacuation of younger deposits and preservation of older deposits. Much of the sediment transported onto valley floors via debris flows is deposited, and then is evacuated over longer times. Volumes and residence times of stored sediment in these deposits at the transition from debris flow to fluvial evacuation, and their associated width of valley floors, vary throughout a network. Export volumes and frequencies from tributaries are controls on deposit volumes and may control valley widening of mainstem valley floors. In addition, closely spaced tributaries may exert composite effects on valley floor landforms. It is hypothesized that the volumes of sediment stored at confluences increases with contributing watershed area of tributaries to the point where tributary slopes are low enough to cause most debris flows to be deposited within tributary valleys instead of in the mainstem valley. In four ~1 km reaches with contributing watershed areas of 0.3 to 5.0 km², field surveys provided measures of width of valley floors and volume of deposits, and radiocarbon dating of charcoal provided residence times of sediment in these deposits. Mean residence times of reaches vary between 1.1 and 2.5 kyr. Exponential distributions fit to residence times within two of the reaches imply evacuation of sediment independent of deposit ages. Power-law fits to residence times of the other two reaches imply age-dependent evacuation of deposits. Distribution shapes of residence times, and their means, do not vary systematically with contributing watershed area of mainstems. Mean width of mainstem valley floors increases with contributing watershed areas of both mainstems and their respective tributaries. Volumes of sediment stored on the valley floor increase with contributing areas of mainstems, and these volumes at tributary junctions peaked at tributary contributing areas of ~0.1 km². Percentage of basin denudation entering storage decreases with contributing area of mainstem. This decrease may be due to increasing percentages of sediment supply via fluvial transport for larger watersheds, and much, if not most, of this supply routes through the system quickly. Close

• 70. [Article] Fecundity and longevity in Tribolium castaneum : a selection experiment

  Recent experimental and theoretical work has examined the possible genetic causes of senescence. These are reviewed, and four types of factors are found to be responsible for the evolution of senescence ...

  Citation × Citation Citation Abstract Copy Title: Fecundity and longevity in Tribolium castaneum : a selection experiment Author: Treneman, Nancy C. Recent experimental and theoretical work has examined the possible genetic causes of senescence. These are reviewed, and four types of factors are found to be responsible for the evolution of senescence and age specific fecundity curves: 1. Age specific mortality schedules, 2.Density dependent factors, 3. Density independent factors, 4. Random fluctuations in environmental conditions. A discussion of al leles with different age specific effects explores their behavior under a variety of mortal ity schedules. An experiment involving natural and artificial selection for high fecundity at 10 and 100 days of age in a laboratory population of Iriloilan LAatamgam resulted in significant increases in 100 day fecundity in al 1 lines. No change in 10 day fecundity was seen in any I ine. Percent mortal ity was not changed by selection. The heritabil ity of fecundity at 10 and 100 days was measured: heritabil ity was estimated to be .53 + .35 for 10 day fecundity and zero at 100 days. These results are shown to support the hypothesis that this I, cAliamlam population is polymorphic with respect to age specific fecundity distributions and that the life history strategy of this organism has been molded by fluctuating juvenile mortality. Title: Fecundity and longevity in Tribolium castaneum : a selection experiment Author: Treneman, Nancy C. Recent experimental and theoretical work has examined the possible genetic causes of senescence. These are reviewed, and four types of factors are found to be responsible for the evolution of senescence and age specific fecundity curves: 1. Age specific mortality schedules, 2.Density dependent factors, 3. Density independent factors, 4. Random fluctuations in environmental conditions. A discussion of al leles with different age specific effects explores their behavior under a variety of mortal ity schedules. An experiment involving natural and artificial selection for high fecundity at 10 and 100 days of age in a laboratory population of Iriloilan LAatamgam resulted in significant increases in 100 day fecundity in al 1 lines. No change in 10 day fecundity was seen in any I ine. Percent mortal ity was not changed by selection. The heritabil ity of fecundity at 10 and 100 days was measured: heritabil ity was estimated to be .53 + .35 for 10 day fecundity and zero at 100 days. These results are shown to support the hypothesis that this I, cAliamlam population is polymorphic with respect to age specific fecundity distributions and that the life history strategy of this organism has been molded by fluctuating juvenile mortality. Close

• 71. [Article] The relationship between sibling status and sex-role preference among preschool-aged children

  The primary purpose of this study was to explore the relationships between the variables of sex, age, sibling status, age relationship of sibling, age spacing between siblings and sex-role preference among preschool-aged ...

  Citation × Citation Citation Abstract Copy Title: The relationship between sibling status and sex-role preference among preschool-aged children Author: Easton, Linda The primary purpose of this study was to explore the relationships between the variables of sex, age, sibling status, age relationship of sibling, age spacing between siblings and sex-role preference among preschool-aged children. Seventy-one children, 32 boys and 39 girls, ranging in ages from two-years-eleven-months to five-years-seven-months, served as subjects. All subjects came from two-child, intact families from the upper and middle socioeconomic levels. The It Scale for Children (ITSC) was used to measure the subjects' sex-role o.references. Five null hypotheses were generated, and the analysis of variance was used to test these hypotheses. F-values were generated for tests of the major variables and their interaction effects. The .05 level of significance was chosen as the criterion of statistical significance. Findings are summarized below. There was a significant difference between the sex-role preference scores of boys and girls (F 8. 201, p <. 05). Boys had significantly higher own-sex-role preference scores than girls. A study of the mean values associated with the sex interaction effect comparisons, while not statistically significant, revealed tendencies in the data which further substantiated this finding. There was no significant difference between the sex-role preference scores of older and younger subjects. A study of the mean values associated with the main effect of age and its interaction effects, however, although not statistically significant, indicated a tendency for older subjects to have higher own-sex-role preference scores than younger subjects in all but two age interaction comparisons. There was no significant difference between the sex-role preference scores of subjects with an opposite-sex sibling and those with a same-sex sibling. A study of mean values associated with the sibling status interaction effect comparisons further substantiated this finding. There was no significant difference between the sex-role preference scores of subjects with a sibling older than they and subjects with a sibling younger than they. A study of the mean values associated with all Sibling Status x Age Relationship (SS x AR) interaction effect comparisons, while not statistically significant, revealed a number of interesting tendencies. In all these interactions, (1) subjects with a same-sex sibling older than they had slightly higher own-sex-role preference 'scores than subjects with an opposite-sex sibling older than they, (2) subjects who had a same-sex sibling older than they had slightly higher own-sex-role preference scores than subjects with a same-sex sibling younger than they, and (3) subjects who had an opposite-sex sibling older than they had lower own-sex-role preference scores than subjects with an opposite-sex sibling younger than they. There was no significant difference between the sex-role preference scores of subjects in the close age spacing and those in the distant age spacing groups. A study of the mean values associated with the Sibling Status x Age Relationship of Sibling x Age Spacing between Siblings (SS x AR x AS) interaction effect comparisons indicated interesting trends. In this interaction, (1) subjects with an older same-sex sibling in the close age spacing group had slightly higher own-sex-role preference scores than subjects with an older same-sex sibling in the distant age spacing group, and (2) subjects with an older opposite-sex sibling in the close age spacing group tended to have lower own-sex-role preference scores than subjects with an older opposite-sex sibling in the distant age spacing group. It should be emphasized that due to the statistical non-sig-nificance of many of the findings and the variety of limitations encountered in this study, extreme caution must be exercised in interpreting the results obtained. All significant findings and tendencies obtained were related to both theoretical and research literature. Limitations of the study and suggestions for future research were also discussed. Title: The relationship between sibling status and sex-role preference among preschool-aged children Author: Easton, Linda The primary purpose of this study was to explore the relationships between the variables of sex, age, sibling status, age relationship of sibling, age spacing between siblings and sex-role preference among preschool-aged children. Seventy-one children, 32 boys and 39 girls, ranging in ages from two-years-eleven-months to five-years-seven-months, served as subjects. All subjects came from two-child, intact families from the upper and middle socioeconomic levels. The It Scale for Children (ITSC) was used to measure the subjects' sex-role o.references. Five null hypotheses were generated, and the analysis of variance was used to test these hypotheses. F-values were generated for tests of the major variables and their interaction effects. The .05 level of significance was chosen as the criterion of statistical significance. Findings are summarized below. There was a significant difference between the sex-role preference scores of boys and girls (F 8. 201, p <. 05). Boys had significantly higher own-sex-role preference scores than girls. A study of the mean values associated with the sex interaction effect comparisons, while not statistically significant, revealed tendencies in the data which further substantiated this finding. There was no significant difference between the sex-role preference scores of older and younger subjects. A study of the mean values associated with the main effect of age and its interaction effects, however, although not statistically significant, indicated a tendency for older subjects to have higher own-sex-role preference scores than younger subjects in all but two age interaction comparisons. There was no significant difference between the sex-role preference scores of subjects with an opposite-sex sibling and those with a same-sex sibling. A study of mean values associated with the sibling status interaction effect comparisons further substantiated this finding. There was no significant difference between the sex-role preference scores of subjects with a sibling older than they and subjects with a sibling younger than they. A study of the mean values associated with all Sibling Status x Age Relationship (SS x AR) interaction effect comparisons, while not statistically significant, revealed a number of interesting tendencies. In all these interactions, (1) subjects with a same-sex sibling older than they had slightly higher own-sex-role preference 'scores than subjects with an opposite-sex sibling older than they, (2) subjects who had a same-sex sibling older than they had slightly higher own-sex-role preference scores than subjects with a same-sex sibling younger than they, and (3) subjects who had an opposite-sex sibling older than they had lower own-sex-role preference scores than subjects with an opposite-sex sibling younger than they. There was no significant difference between the sex-role preference scores of subjects in the close age spacing and those in the distant age spacing groups. A study of the mean values associated with the Sibling Status x Age Relationship of Sibling x Age Spacing between Siblings (SS x AR x AS) interaction effect comparisons indicated interesting trends. In this interaction, (1) subjects with an older same-sex sibling in the close age spacing group had slightly higher own-sex-role preference scores than subjects with an older same-sex sibling in the distant age spacing group, and (2) subjects with an older opposite-sex sibling in the close age spacing group tended to have lower own-sex-role preference scores than subjects with an older opposite-sex sibling in the distant age spacing group. It should be emphasized that due to the statistical non-sig-nificance of many of the findings and the variety of limitations encountered in this study, extreme caution must be exercised in interpreting the results obtained. All significant findings and tendencies obtained were related to both theoretical and research literature. Limitations of the study and suggestions for future research were also discussed. Close

• 72. [Article] Ecosystem effects of vegetation removal in coastal Oregon Douglas-fir experimental plantations : impacts on ecosystem production, tree growth, nutrients, and soils

  Effects of partial understory removal on belowground and aboveground ecosystem properties were investigated in 5 and 15 yr old Douglas-fir (Pseudotsuga menziesll (Mirb.) Franco) experimental plantations ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem effects of vegetation removal in coastal Oregon Douglas-fir experimental plantations : impacts on ecosystem production, tree growth, nutrients, and soils Author: Yildiz, Oktay Effects of partial understory removal on belowground and aboveground ecosystem properties were investigated in 5 and 15 yr old Douglas-fir (Pseudotsuga menziesll (Mirb.) Franco) experimental plantations in western Oregon. Seedling survival was not affected by understory removal at age 5 yr. But through age 15 yr, understory removal increased seedling survival up to 30% on some of the plots. At plantation age 5 yr, tree biomass accumulation was increased nearly 12-fold with complete shrub and herb removal from the sites. However, total aboveground biomass was the same among treatments at age 5 yr. At plantation age 15 yr, tree biomass accumulation was 336% greater with complete understory removal from the Douglas-fir only plots (DFO). Even though Douglas-fir needle N concentrations were significantly higher on DFC plots at age 5 yr, this difference was not detected at plantation age 15 yr. However, Douglas-fir foliar nutrient concentrations decreased significantly between 5 and 15 yr for: Ca, Mn, Fe, Cu, B, and Zn. The total aboveground N pool was greater for DEC plots due to the greater amount of aboveground biomass present in shrubs and herbs at age 5 yr. From plantation age 5 to 15 yr, the total aboveground N pool dramatically increased. However, the aboveground total N pool was not significantly different among plots. On the other hand, the aboveground P pool was 86% and Ca pool 87% higher on DFO than on DFC plots. At age 15 yr, the upper 15 cm of soil had more than 20% greater bulk density on DFO than on DEC plots. Soil C concentration in the <2 mm soil fraction was reduced by 27% with complete understory removal at age 5 yr. DFO plot soil had 49% less exchangeable Ca than DFC plot soil by age 15 yr. At age 5 yr, net mineralizable NH4 was the lowest on DFO plots. However, incorporation of organic matter into mineral soil during vegetation removal, and the decreased demand in plant uptake, increased total inorganic N on exchange resins in DFO soil. In the upper 15cm of soil, [delta][superscript]15 N was enriched due to understory removal. Title: Ecosystem effects of vegetation removal in coastal Oregon Douglas-fir experimental plantations : impacts on ecosystem production, tree growth, nutrients, and soils Author: Yildiz, Oktay Effects of partial understory removal on belowground and aboveground ecosystem properties were investigated in 5 and 15 yr old Douglas-fir (Pseudotsuga menziesll (Mirb.) Franco) experimental plantations in western Oregon. Seedling survival was not affected by understory removal at age 5 yr. But through age 15 yr, understory removal increased seedling survival up to 30% on some of the plots. At plantation age 5 yr, tree biomass accumulation was increased nearly 12-fold with complete shrub and herb removal from the sites. However, total aboveground biomass was the same among treatments at age 5 yr. At plantation age 15 yr, tree biomass accumulation was 336% greater with complete understory removal from the Douglas-fir only plots (DFO). Even though Douglas-fir needle N concentrations were significantly higher on DFC plots at age 5 yr, this difference was not detected at plantation age 15 yr. However, Douglas-fir foliar nutrient concentrations decreased significantly between 5 and 15 yr for: Ca, Mn, Fe, Cu, B, and Zn. The total aboveground N pool was greater for DEC plots due to the greater amount of aboveground biomass present in shrubs and herbs at age 5 yr. From plantation age 5 to 15 yr, the total aboveground N pool dramatically increased. However, the aboveground total N pool was not significantly different among plots. On the other hand, the aboveground P pool was 86% and Ca pool 87% higher on DFO than on DFC plots. At age 15 yr, the upper 15 cm of soil had more than 20% greater bulk density on DFO than on DEC plots. Soil C concentration in the <2 mm soil fraction was reduced by 27% with complete understory removal at age 5 yr. DFO plot soil had 49% less exchangeable Ca than DFC plot soil by age 15 yr. At age 5 yr, net mineralizable NH4 was the lowest on DFO plots. However, incorporation of organic matter into mineral soil during vegetation removal, and the decreased demand in plant uptake, increased total inorganic N on exchange resins in DFO soil. In the upper 15cm of soil, [delta][superscript]15 N was enriched due to understory removal. Close

• 73. [Article] Distribution, abundance, and emigration of juvenile steelhead (Oncorhynchus mykiss), and analysis of stream habitat in the Steamboat Creek Basin, Oregon

  Snorkel dive estimates and an inventory of stream habitat of the juvenile steelhead (Oncorhynchus mykiss) population in the Steamboat Creek basin were made in the summers of 1987 and 1988. Emigration was monitored ...

  Citation × Citation Citation Abstract Copy Title: Distribution, abundance, and emigration of juvenile steelhead (Oncorhynchus mykiss), and analysis of stream habitat in the Steamboat Creek Basin, Oregon Author: Dambacher, Jeffrey M. Snorkel dive estimates and an inventory of stream habitat of the juvenile steelhead (Oncorhynchus mykiss) population in the Steamboat Creek basin were made in the summers of 1987 and 1988. Emigration was monitored by fish trapping from spring through fall of 1988. Distribution, abundance, and habitat utilization of juvenile steelhead were affected by stream size and temperature. The majority (65%) of age >1 fish were in two mainstem channels, whereas numbers of age 0 fish were more evenly distributed throughout the basin. Age >1 fish significantly (P<O.005) increased their use of riffles with depth, and avoided shallow riffles. Where riffles were apparently too shallow, age >1 steelhead utilized pool habitat to a greater extent. Age >1 steelhead greatly avoided glides in all sizes of channels. Age 0 steelhead appeared to be less restricted in their choice of habitat than age >1 fish. Age 0 fish, presumably by virtue of a smaller body size, showed only slightly increased use of riffles with depth. Both age 0 and >1 steelhead increased their use of riffles in streams with higher temperature regimes. Densities of age >1 fish in channels with large boulder substrate increased significantly (p=O.02) with mean riffle depth, probably as a function of more wetted area being useable in streams with deep riffles, and more feeding microhabitats being afforded by rough channels. Densities of age 0 fish did not appear to be affected by the range of stream sizes studied, or by channel roughness, but were low in all channels with high stream temperatures. Compared to other steelhead producing streams, Steamboat Creek had low summer rearing densities, small smolts, and an exceptionally high proportion of fish emigrating as parr (considered to be at least one year away from development of smolt characteristics). Roughly 120,000 age 0 steelhead, 60,000 parr, and 4,100 steelhead smolts were estimated to have emigrated from the basin. Most parr emigrated in the spring when stream flows were high, whereas the majority of age 0 fish emigrated during summer base flow recession. I suggest that parr emigration from Steamboat Creek may be a life history adaptation that takes advantage of rearing conditions downstream in the North Umpqua River. Title: Distribution, abundance, and emigration of juvenile steelhead (Oncorhynchus mykiss), and analysis of stream habitat in the Steamboat Creek Basin, Oregon Author: Dambacher, Jeffrey M. Snorkel dive estimates and an inventory of stream habitat of the juvenile steelhead (Oncorhynchus mykiss) population in the Steamboat Creek basin were made in the summers of 1987 and 1988. Emigration was monitored by fish trapping from spring through fall of 1988. Distribution, abundance, and habitat utilization of juvenile steelhead were affected by stream size and temperature. The majority (65%) of age >1 fish were in two mainstem channels, whereas numbers of age 0 fish were more evenly distributed throughout the basin. Age >1 fish significantly (P<O.005) increased their use of riffles with depth, and avoided shallow riffles. Where riffles were apparently too shallow, age >1 steelhead utilized pool habitat to a greater extent. Age >1 steelhead greatly avoided glides in all sizes of channels. Age 0 steelhead appeared to be less restricted in their choice of habitat than age >1 fish. Age 0 fish, presumably by virtue of a smaller body size, showed only slightly increased use of riffles with depth. Both age 0 and >1 steelhead increased their use of riffles in streams with higher temperature regimes. Densities of age >1 fish in channels with large boulder substrate increased significantly (p=O.02) with mean riffle depth, probably as a function of more wetted area being useable in streams with deep riffles, and more feeding microhabitats being afforded by rough channels. Densities of age 0 fish did not appear to be affected by the range of stream sizes studied, or by channel roughness, but were low in all channels with high stream temperatures. Compared to other steelhead producing streams, Steamboat Creek had low summer rearing densities, small smolts, and an exceptionally high proportion of fish emigrating as parr (considered to be at least one year away from development of smolt characteristics). Roughly 120,000 age 0 steelhead, 60,000 parr, and 4,100 steelhead smolts were estimated to have emigrated from the basin. Most parr emigrated in the spring when stream flows were high, whereas the majority of age 0 fish emigrated during summer base flow recession. I suggest that parr emigration from Steamboat Creek may be a life history adaptation that takes advantage of rearing conditions downstream in the North Umpqua River. Close

• 74. [Article] Erosion by rivers and transport pathways in the ocean: A provenance tool using 40Ar--39Ar incremental heating on fine-grained sediment

  We use Ar-40-Ar-39 incremental heating to fingerprint bulk fluvial sediment entering the northeast Pacific Ocean, with the long-term intent of tracking sediment source and transport changes from the terrestrial ...

  Citation × Citation Citation Abstract Copy Title: Erosion by rivers and transport pathways in the ocean: A provenance tool using 40Ar--39Ar incremental heating on fine-grained sediment Author: Duncan, Robert A., Pisias, Nicklas G., VanLaningham, Sam We use Ar-40-Ar-39 incremental heating to fingerprint bulk fluvial sediment entering the northeast Pacific Ocean, with the long-term intent of tracking sediment source and transport changes from the terrestrial system to the marine environment through time. We show reproducible age spectra from individual rivers accounting for the majority of sediment delivered to the Pacific margin. Two tests are performed to confirm the validity of the bulk sediment Ar-40-Ar-39 incremental heating measurements and to address why polymineralic sediment might yield concordant age steps. The first model tests, in light of bulk mineralogy and diffusion of Ar from silicates, whether measured K/Ca spectra (measured from Ar-39 and Ar-37, respectively) are consistent with typical values for K- and Ca-bearing minerals. Calculations show that the bulk mineralogy is reflected in the outgassing K/Ca spectra and identify plagioclase as the dominant mineral contributing to the plateau-defining portion of the age spectra. A second model predicts bulk sediment ages from integrated bedrock cooling age-area estimates in order to examine whether bulk sediment plateau ages are representative of the average cooling age of rocks from a given river basin. Calculated and observed ages are notably similar in three river basins when topographic and lithologic effects are accounted for. Overall, this technique shows considerable promise, not only in tracking individual terrigenous sources in the marine realm but also for understanding processes such as erosion and sediment transport in terrestrial systems. Title: Erosion by rivers and transport pathways in the ocean: A provenance tool using 40Ar--39Ar incremental heating on fine-grained sediment Author: Duncan, Robert A., Pisias, Nicklas G., VanLaningham, Sam We use Ar-40-Ar-39 incremental heating to fingerprint bulk fluvial sediment entering the northeast Pacific Ocean, with the long-term intent of tracking sediment source and transport changes from the terrestrial system to the marine environment through time. We show reproducible age spectra from individual rivers accounting for the majority of sediment delivered to the Pacific margin. Two tests are performed to confirm the validity of the bulk sediment Ar-40-Ar-39 incremental heating measurements and to address why polymineralic sediment might yield concordant age steps. The first model tests, in light of bulk mineralogy and diffusion of Ar from silicates, whether measured K/Ca spectra (measured from Ar-39 and Ar-37, respectively) are consistent with typical values for K- and Ca-bearing minerals. Calculations show that the bulk mineralogy is reflected in the outgassing K/Ca spectra and identify plagioclase as the dominant mineral contributing to the plateau-defining portion of the age spectra. A second model predicts bulk sediment ages from integrated bedrock cooling age-area estimates in order to examine whether bulk sediment plateau ages are representative of the average cooling age of rocks from a given river basin. Calculated and observed ages are notably similar in three river basins when topographic and lithologic effects are accounted for. Overall, this technique shows considerable promise, not only in tracking individual terrigenous sources in the marine realm but also for understanding processes such as erosion and sediment transport in terrestrial systems. Close

• 75. [Article] Effects of Aging on the Molecular Circadian Oscillations in Drosophila

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Informa Healthcare USA, Inc. and can be found at: http://informahealthcare.com...

  Citation × Citation Citation Abstract Copy Title: Effects of Aging on the Molecular Circadian Oscillations in Drosophila Author: Guzik, Elzbieta M., Giebultowicz, Jadwiga M., Rakshit, Kuntol, Krishnan, Natraj, Pyza, Elzbieta This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Informa Healthcare USA, Inc. and can be found at: http://informahealthcare.com/cbi. Title: Effects of Aging on the Molecular Circadian Oscillations in Drosophila Author: Guzik, Elzbieta M., Giebultowicz, Jadwiga M., Rakshit, Kuntol, Krishnan, Natraj, Pyza, Elzbieta This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Informa Healthcare USA, Inc. and can be found at: http://informahealthcare.com/cbi. Close

• 76. [Article] Age determination and age-specific reproduction in raccoons in northwestern Oregon

  Citation × Citation Citation Abstract Copy Title: Age determination and age-specific reproduction in raccoons in northwestern Oregon Author: Fiero, Brad C. Title: Age determination and age-specific reproduction in raccoons in northwestern Oregon Author: Fiero, Brad C. Close

• 77. [Article] A Comparative Analysis of Rodent Species Shows Oxidative Stress Resilience and HSP70 Expression Levels Correlate with Species Longevity

  Researchers of healthy aging have determined trends between a species’ body mass and its maximal life span (MLSP). Actual MLSPs are then compared to predicted MLSPs and reported as a longevity quotient ...

  Citation × Citation Citation Abstract Copy Title: A Comparative Analysis of Rodent Species Shows Oxidative Stress Resilience and HSP70 Expression Levels Correlate with Species Longevity Author: Sarker, Minhazur R. Researchers of healthy aging have determined trends between a species’ body mass and its maximal life span (MLSP). Actual MLSPs are then compared to predicted MLSPs and reported as a longevity quotient (LQ). Long-lived mammals, such as humans and naked mole rats (NMR), have LQs ranging from 5.0 to 10.0, meaning they live 5 to 10 times longer than expected. This LQ similarity leads researchers to believe the NMR may be an ideal model organism for human aging research. Among the proposed theories of aging, the oxidative stress theory, which states that cells have a chronic presence of oxidative stress that increases with age, is one of the most widely accepted. Our work delves deeper into this theory as it pertains to the NMR. We observed that NMR fibroblasts (NMRFs) have a much greater resilience to menadione, an oxidative stressor, than mouse fibroblasts (MFs), which, under the oxidative stress theory of aging, may explain why NMR have delayed onsets of aging phenotypes. We then observed that compared to MFs and rat hepatocytes, NMRFs have a greater basal expression of heat-­shock protein 70 (HSP70), a primary role player in homeostatic responses to oxidative stress. This greater HSP70 expression may grant the NMRFs a stronger initial defense allowing them to maintain viability at greater levels of oxidative stress. Finally, our work investigated the use of geranylgeranyl acetone (GGA) as an HSP70 inducer to slow the insults from oxidative stress. We were not able to show GGA as an efficient HSP70 inducer. Ultimately, our work has discovered some key aspects of the naked mole rat, however, further investigation is needed to determine if naked mole rats may serve as the ideal model species for human healthy aging research. Title: A Comparative Analysis of Rodent Species Shows Oxidative Stress Resilience and HSP70 Expression Levels Correlate with Species Longevity Author: Sarker, Minhazur R. Researchers of healthy aging have determined trends between a species’ body mass and its maximal life span (MLSP). Actual MLSPs are then compared to predicted MLSPs and reported as a longevity quotient (LQ). Long-lived mammals, such as humans and naked mole rats (NMR), have LQs ranging from 5.0 to 10.0, meaning they live 5 to 10 times longer than expected. This LQ similarity leads researchers to believe the NMR may be an ideal model organism for human aging research. Among the proposed theories of aging, the oxidative stress theory, which states that cells have a chronic presence of oxidative stress that increases with age, is one of the most widely accepted. Our work delves deeper into this theory as it pertains to the NMR. We observed that NMR fibroblasts (NMRFs) have a much greater resilience to menadione, an oxidative stressor, than mouse fibroblasts (MFs), which, under the oxidative stress theory of aging, may explain why NMR have delayed onsets of aging phenotypes. We then observed that compared to MFs and rat hepatocytes, NMRFs have a greater basal expression of heat-­shock protein 70 (HSP70), a primary role player in homeostatic responses to oxidative stress. This greater HSP70 expression may grant the NMRFs a stronger initial defense allowing them to maintain viability at greater levels of oxidative stress. Finally, our work investigated the use of geranylgeranyl acetone (GGA) as an HSP70 inducer to slow the insults from oxidative stress. We were not able to show GGA as an efficient HSP70 inducer. Ultimately, our work has discovered some key aspects of the naked mole rat, however, further investigation is needed to determine if naked mole rats may serve as the ideal model species for human healthy aging research. Close

• 78. [Article] Life history examination of darkblotched rockfish (Sebastes crameri) off the Oregon coast

  The growth, size and age composition, mortality and reproduction of darkblotched rockfish (Sebastes crameri) were examined using fishery data and analysis of fish characteristics for samples collected ...

  Citation × Citation Citation Abstract Copy Title: Life history examination of darkblotched rockfish (Sebastes crameri) off the Oregon coast Author: Nichol, Daniel Gerard The growth, size and age composition, mortality and reproduction of darkblotched rockfish (Sebastes crameri) were examined using fishery data and analysis of fish characteristics for samples collected of f the Oregon coast. A total of 1060 fish, caught by commercial groundfish and shrimp trawlers operating out of Newport, Coos Bay and Astoria, were collected between July 1986 and July 1987. S. crameri were found to be slow growing and longlived reaching ages in excess of 100 years. The composition of fish captured with commercial groundfish trawl gear (excluding shrimp gear) was dominated by recent recruits ranging from 6 to 9 years of age. The age at full recruitment to commercial groundfish gear was 7 years. Assuming constant recruitment and mortality after 1978, total instantaneous mortality (Z) for recent recruits may have been as high as 0.42. This estimate may be inflated, however, if the 1978-1980 yearclasses were strong relative to earlier yearclasses. The timing of major reproductive events was protracted. Insemination occurred from September to December, fertilization from December to February, and parturition from December to March. Fifty percent of the females were mature at an age of 8 years and a total length (TL) of 36.7 cm, whereas males attained 50% maturity at an age of 5 years and 29.7 cm TL. Fecundity increased nonlinearly with fish size and ranged from 19,815 to 489,064 oocytes/ovary pair. Based on its longevity, its relatively young age at full recruitment, and its age at maturity, S. crameri appears vulnerable to overexploitation. Title: Life history examination of darkblotched rockfish (Sebastes crameri) off the Oregon coast Author: Nichol, Daniel Gerard The growth, size and age composition, mortality and reproduction of darkblotched rockfish (Sebastes crameri) were examined using fishery data and analysis of fish characteristics for samples collected of f the Oregon coast. A total of 1060 fish, caught by commercial groundfish and shrimp trawlers operating out of Newport, Coos Bay and Astoria, were collected between July 1986 and July 1987. S. crameri were found to be slow growing and longlived reaching ages in excess of 100 years. The composition of fish captured with commercial groundfish trawl gear (excluding shrimp gear) was dominated by recent recruits ranging from 6 to 9 years of age. The age at full recruitment to commercial groundfish gear was 7 years. Assuming constant recruitment and mortality after 1978, total instantaneous mortality (Z) for recent recruits may have been as high as 0.42. This estimate may be inflated, however, if the 1978-1980 yearclasses were strong relative to earlier yearclasses. The timing of major reproductive events was protracted. Insemination occurred from September to December, fertilization from December to February, and parturition from December to March. Fifty percent of the females were mature at an age of 8 years and a total length (TL) of 36.7 cm, whereas males attained 50% maturity at an age of 5 years and 29.7 cm TL. Fecundity increased nonlinearly with fish size and ranged from 19,815 to 489,064 oocytes/ovary pair. Based on its longevity, its relatively young age at full recruitment, and its age at maturity, S. crameri appears vulnerable to overexploitation. Close

• 79. [Article] A comparison of the attributes of nonmetropolitan preretirees who plan to age in place to preretirees who plan to in-migrate : for use in designing community revitalization

  A growing number of nonmetropolitan communities have chosen to pursue nontraditional avenues for economic development including the promotion of the nonmetropolitan area to older adults who may choose ...

  Citation × Citation Citation Abstract Copy Title: A comparison of the attributes of nonmetropolitan preretirees who plan to age in place to preretirees who plan to in-migrate : for use in designing community revitalization Author: Barlow-Pieterick, Marilyn A growing number of nonmetropolitan communities have chosen to pursue nontraditional avenues for economic development including the promotion of the nonmetropolitan area to older adults who may choose to migrate after retirement. The purpose of this study was to help community leaders in nonmetropolitan areas make informed decisions if they choose to revitalize their town through the aid of immigration and retention of retirees, by knowing what infrastructure to plan for based on the neighborhood, housing, and support service preferences of future nonmetropolitan retirees. This prospective study compared two populations: preretirees who planned to migrate to nonmetropolitan areas during the first 10 years of retirement and preretirees who planned to age in place in nonmetropolitan areas upon retirement by (1) age integrated/ age segregated neighborhood preference; (2) housing tenure and structure preference; (3) support service preference of a hospital and/or family members; and (4) the socio-demographic variables of marital status, health status, current income level, and number of sources of retirement income. An age stratified random sample of preretirees from two states (N=1,175), Oregon and Utah, was included in the study. Statistical analyses included descriptive statistics and chi-square and one t-test to test nine null hypotheses. Migrant respondents differed in their preference for neighborhoods with older residents (p=.00000), preference to rent (p=.00002), and tendency to feel that family in the community was important (p=.00031). Migrants differed significantly in their marital status (p=.01292), in that more were unmarried. With regard to health status (p=.02752), more age in place reported excellent and fair/poor health as opposed to migrants' very good and good health. Nonmetropolitan community leaders interested in economic revitalization through the attraction of and retention of elderly retirees may want to consider including in their community the following: housing that tends to be more age segregated than age integrated, single family dwellings that can be rented, a hospital, and formal support services that may be needed if the informal support of family and friends is not available. Title: A comparison of the attributes of nonmetropolitan preretirees who plan to age in place to preretirees who plan to in-migrate : for use in designing community revitalization Author: Barlow-Pieterick, Marilyn A growing number of nonmetropolitan communities have chosen to pursue nontraditional avenues for economic development including the promotion of the nonmetropolitan area to older adults who may choose to migrate after retirement. The purpose of this study was to help community leaders in nonmetropolitan areas make informed decisions if they choose to revitalize their town through the aid of immigration and retention of retirees, by knowing what infrastructure to plan for based on the neighborhood, housing, and support service preferences of future nonmetropolitan retirees. This prospective study compared two populations: preretirees who planned to migrate to nonmetropolitan areas during the first 10 years of retirement and preretirees who planned to age in place in nonmetropolitan areas upon retirement by (1) age integrated/ age segregated neighborhood preference; (2) housing tenure and structure preference; (3) support service preference of a hospital and/or family members; and (4) the socio-demographic variables of marital status, health status, current income level, and number of sources of retirement income. An age stratified random sample of preretirees from two states (N=1,175), Oregon and Utah, was included in the study. Statistical analyses included descriptive statistics and chi-square and one t-test to test nine null hypotheses. Migrant respondents differed in their preference for neighborhoods with older residents (p=.00000), preference to rent (p=.00002), and tendency to feel that family in the community was important (p=.00031). Migrants differed significantly in their marital status (p=.01292), in that more were unmarried. With regard to health status (p=.02752), more age in place reported excellent and fair/poor health as opposed to migrants' very good and good health. Nonmetropolitan community leaders interested in economic revitalization through the attraction of and retention of elderly retirees may want to consider including in their community the following: housing that tends to be more age segregated than age integrated, single family dwellings that can be rented, a hospital, and formal support services that may be needed if the informal support of family and friends is not available. Close

• 80. [Article] The cost of fisheries induced evolution. An example using data for North-East Atlantic cod

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: The cost of fisheries induced evolution. An example using data for North-East Atlantic cod Author: Reithe, Siv Abstract only. Title: The cost of fisheries induced evolution. An example using data for North-East Atlantic cod Author: Reithe, Siv Abstract only. Close

• 81. [Article] urap cue poster.pptx

  Citation × Citation Citation Abstract Copy Title: urap cue poster.pptx Author: McClelland, Megan M., Harper, Kevin G. Title: urap cue poster.pptx Author: McClelland, Megan M., Harper, Kevin G. Close

• 82. [Article] HarperKevin.pdf

  Citation × Citation Citation Abstract Copy Title: HarperKevin.pdf Author: McClelland, Megan M., Harper, Kevin G. Title: HarperKevin.pdf Author: McClelland, Megan M., Harper, Kevin G. Close

• 83. [Article] Planning a Willamette Valley dwelling to meet the needs of a couple past middle life

  Citation × Citation Citation Abstract Copy Title: Planning a Willamette Valley dwelling to meet the needs of a couple past middle life Author: Nichols, Addreen Title: Planning a Willamette Valley dwelling to meet the needs of a couple past middle life Author: Nichols, Addreen Close

• 84. [Article] An Increase in the Association of GluN2B Containing NMDA Receptors with Membrane Scaffolding Proteins Was Related to Memory Declines during Aging

  This is the publisher’s final pdf. The published article is copyrighted by Society for Neuroscience and can be found at: http://www.jneurosci.org/.

  Citation × Citation Citation Abstract Copy Title: An Increase in the Association of GluN2B Containing NMDA Receptors with Membrane Scaffolding Proteins Was Related to Memory Declines during Aging Author: Zamzow, Daniel R., Shumaker, Michelle, Elias, Valerie, Larson, Cameron, Magnusson, Kathy R. This is the publisher’s final pdf. The published article is copyrighted by Society for Neuroscience and can be found at: http://www.jneurosci.org/. Title: An Increase in the Association of GluN2B Containing NMDA Receptors with Membrane Scaffolding Proteins Was Related to Memory Declines during Aging Author: Zamzow, Daniel R., Shumaker, Michelle, Elias, Valerie, Larson, Cameron, Magnusson, Kathy R. This is the publisher’s final pdf. The published article is copyrighted by Society for Neuroscience and can be found at: http://www.jneurosci.org/. Close

• 85. [Article] Designing and Creating the Oregon State Age and Disability Simulation Suit

  Citation × Citation Citation Abstract Copy Title: Designing and Creating the Oregon State Age and Disability Simulation Suit Author: Rahrer, Adam P. Title: Designing and Creating the Oregon State Age and Disability Simulation Suit Author: Rahrer, Adam P. Close

• 86. [Article] Shrimp adjust their sex ratio to fluctuating age distributions

  This is the publisher’s final pdf. The published article is copyrighted by Evolutionary Ecology and can be found at: http://www.evolutionary-ecology.com/.

  Citation × Citation Citation Abstract Copy Title: Shrimp adjust their sex ratio to fluctuating age distributions Author: Hannah, Robert W., Charnov, Eric L. This is the publisher’s final pdf. The published article is copyrighted by Evolutionary Ecology and can be found at: http://www.evolutionary-ecology.com/. Title: Shrimp adjust their sex ratio to fluctuating age distributions Author: Hannah, Robert W., Charnov, Eric L. This is the publisher’s final pdf. The published article is copyrighted by Evolutionary Ecology and can be found at: http://www.evolutionary-ecology.com/. Close

• 87. [Article] Geochronology of Galapagos seamounts

  Lavas from seamounts of the central Galápagos Platform and the Carnegie Ridge increase in age with distance from the western edge of the platform, consistent with a hotspot model for the generation of ...

  Citation × Citation Citation Abstract Copy Title: Geochronology of Galapagos seamounts Author: Christie, David M., Duncan, Robert A., Sinton, Christopher W. Lavas from seamounts of the central Galápagos Platform and the Carnegie Ridge increase in age with distance from the western edge of the platform, consistent with a hotspot model for the generation of these features. The areal distribution of seamount ages suggests that the pattern of dispersed volcanism seen on the present islands also prevailed between 5 and 6 Ma. Age-distance relationships are consistent with a decrease in the velocity of the Nazca plate relative to the Galápagos hotspot during the past 9 m.y., most likely at ~5 Ma when there was a change in Pacific-hotspot motion. Alternatively, the plate velocity remained constant and volcanism at a single seamount endured up to 7 m.y. lavas from seamounts along the Wolf-Darwin lineament to the northwest of the Galápagos Platform are young (<1 Ma), with the youngest measured ages closest to the platform. Title: Geochronology of Galapagos seamounts Author: Christie, David M., Duncan, Robert A., Sinton, Christopher W. Lavas from seamounts of the central Galápagos Platform and the Carnegie Ridge increase in age with distance from the western edge of the platform, consistent with a hotspot model for the generation of these features. The areal distribution of seamount ages suggests that the pattern of dispersed volcanism seen on the present islands also prevailed between 5 and 6 Ma. Age-distance relationships are consistent with a decrease in the velocity of the Nazca plate relative to the Galápagos hotspot during the past 9 m.y., most likely at ~5 Ma when there was a change in Pacific-hotspot motion. Alternatively, the plate velocity remained constant and volcanism at a single seamount endured up to 7 m.y. lavas from seamounts along the Wolf-Darwin lineament to the northwest of the Galápagos Platform are young (<1 Ma), with the youngest measured ages closest to the platform. Close

• 88. [Article] Aging Giant Pacific Octopus using Beaks and Stylets for Better Stock Structure Assessment

  Despite being a highly charismatic and frequently exhibited organism, Giant Pacific Octopus (Enteroctopus dofleini) population dynamics are poorly understood. Basic monitoring data for this species is limited ...

  Citation × Citation Citation Abstract Copy Title: Aging Giant Pacific Octopus using Beaks and Stylets for Better Stock Structure Assessment Author: Yarbrough, Ashley Despite being a highly charismatic and frequently exhibited organism, Giant Pacific Octopus (Enteroctopus dofleini) population dynamics are poorly understood. Basic monitoring data for this species is limited to bycatch and stomach contents of other fisheries species. An essential step to a better estimation of population size and productivity is to establish efficient procedures and accuracy of a size at age model. The objectives of this research project are to determine the most efficient method for analyzing the hard parts of the Giant Pacific Octopus (GPO), and to provide fisheries management professionals with a weight at age relationship for population stock structure modelling. This information would be extremely useful in reducing bycatch that can cause serious economic issues through fishery closures. Title: Aging Giant Pacific Octopus using Beaks and Stylets for Better Stock Structure Assessment Author: Yarbrough, Ashley Despite being a highly charismatic and frequently exhibited organism, Giant Pacific Octopus (Enteroctopus dofleini) population dynamics are poorly understood. Basic monitoring data for this species is limited to bycatch and stomach contents of other fisheries species. An essential step to a better estimation of population size and productivity is to establish efficient procedures and accuracy of a size at age model. The objectives of this research project are to determine the most efficient method for analyzing the hard parts of the Giant Pacific Octopus (GPO), and to provide fisheries management professionals with a weight at age relationship for population stock structure modelling. This information would be extremely useful in reducing bycatch that can cause serious economic issues through fishery closures. Close

• 89. [Article] Tagged steelhead trout (Salmo gairdneri Richardson) collected in the north Pacific by the Oshoro-Maru, 1982-1985

  Twenty-two steelhead trout (Salmo gairdneri) containing coded wire tags (CWT's) were captured in gillnets fished by the Oshoro-Maru in the Gulf of Alaska and along 180 during 1982-85. These fish originated ...

  Citation × Citation Citation Abstract Copy Title: Tagged steelhead trout (Salmo gairdneri Richardson) collected in the north Pacific by the Oshoro-Maru, 1982-1985 Author: Pearcy, William G., Masuda, Kiyoshi Twenty-two steelhead trout (Salmo gairdneri) containing coded wire tags (CWT's) were captured in gillnets fished by the Oshoro-Maru in the Gulf of Alaska and along 180 during 1982-85. These fish originated from North American streams and hatcheries in British Columbia, Idaho, and Washington. One fish was age 0.1, 16 were age 1.1 and 5 were age 1.2. In 1985, 17% of the steelhead caught had missing adipose fins but did not contain tags. This high proportion of marked hatchery fish and the known fresh water ages of marked fish indicated that many of the steelhead caught by the Oshoro-Maru and other vessels in the Northeast Pacific originated from North American hatcheries. Title: Tagged steelhead trout (Salmo gairdneri Richardson) collected in the north Pacific by the Oshoro-Maru, 1982-1985 Author: Pearcy, William G., Masuda, Kiyoshi Twenty-two steelhead trout (Salmo gairdneri) containing coded wire tags (CWT's) were captured in gillnets fished by the Oshoro-Maru in the Gulf of Alaska and along 180 during 1982-85. These fish originated from North American streams and hatcheries in British Columbia, Idaho, and Washington. One fish was age 0.1, 16 were age 1.1 and 5 were age 1.2. In 1985, 17% of the steelhead caught had missing adipose fins but did not contain tags. This high proportion of marked hatchery fish and the known fresh water ages of marked fish indicated that many of the steelhead caught by the Oshoro-Maru and other vessels in the Northeast Pacific originated from North American hatcheries. Close

• 90. [Article] Two-aged stand management in the Coast Range

  Published September 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Two-aged stand management in the Coast Range Author: Grotta, Amy T., Oregon State University. Extension Service Published September 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Two-aged stand management in the Coast Range Author: Grotta, Amy T., Oregon State University. Extension Service Published September 2013. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 91. [Article] Age-related loss of Nrf2, a novel mechanism for the potential attenuation of xenobiotic detoxification capacity

  Nuclear Factor, Erythroid Derived 2, Like 2 (NFE2L2 or Nrf2) is the primary transcription factor in cellular defense against oxidative and xenobiotic stresses in higher eukaryotes. This basic leucine zipper ...

  Citation × Citation Citation Abstract Copy Title: Age-related loss of Nrf2, a novel mechanism for the potential attenuation of xenobiotic detoxification capacity Author: Smith, Eric Jonathan Nuclear Factor, Erythroid Derived 2, Like 2 (NFE2L2 or Nrf2) is the primary transcription factor in cellular defense against oxidative and xenobiotic stresses in higher eukaryotes. This basic leucine zipper transcription factor regulates over 200 antioxidant, detoxification, and lipid metabolizing genes by binding to the Antioxidant Response Element (ARE; a cis-acting element) as a transcription enhancer. Our group, and others, have identified that the nuclear steady state levels of this highly inducible transcription factor declines with age which coincides with decreased expression of many ARE regulated genes. To elucidate the mechanism(s) involved in lowered Nrf2 levels we used hepatocytes isolated from young and old rats as a relevant cellular model that maintains the aging phenotype with respect to Nrf2 levels. Our results show that steady state Nrf2 levels decline by ~40% with age (N=4, p<0.05), which led us to investigate the multifaceted regulation of Nrf2 homeostasis. Specifically, analysis of Nrf2 mRNA levels, and the rate of Nrf2 protein turnover and translation were investigated. Surprisingly, Keap1-mediated degradation of Nrf2, its primary negative regulator, did not account for the age-related Nrf2 decline, nor did mRNA levels change with age. Rather, Nrf2 protein synthesis declines 5.3-fold with age (N=3, p<0.05). Furthermore, we identify that rno-miR-146a, a key inflammation regulating miRNA, both inhibits Nrf2 translation and increases significantly with age. Taken together, our data suggest that the age-related loss of Nrf2 stems from the loss of its translation and may be mediated through miR regulation. Our lab previously demonstrated in rats, that the age-related loss of Nrf2 consequentially attenuates synthesis and steady state levels of liver glutathione (GSH) synthesis and manifests as a diminished level of GSH. This antioxidant is the most abundant non-protein thiol in most cells and is pivotal for the detoxification of many xenobiotics. The rate-limiting enzyme in GSH synthesis, γ-glutamyl-cysteine ligase (Gcl), is composed of a catalytic (Gclc), and a modulatory (Gclm) subunit. In mice and humans, it is established that Nrf2, through the ARE, regulates Gclc expression. However, this had not been established in rats. From a bioinformatics analysis of the 5’ upstream sequence of the rat Gclc gene, we identified 3 putative AREs (ARE1, ARE3, and ARE4), and one cis-element containing the core but not the flanking nucleotides of the ARE (ARE2). Luciferase reporter plasmids containing each individual ARE were transfected into H4IIE rat hepatoma cells to test for ARE activity. Only one, designated “ARE4”, produced appreciable luciferase activity and was dependent on Nrf2 expression, suggesting that this ARE is a “true” enhancer element. Chromatin immunoprecipitation (ChIP) and qPCR identified that Nrf2 binds ARE4 but not ARE1-3. Further ChIP analysis identified that known partner transcription factors of Nrf2 (small maf, c-Jun and c-Fos) were also bound to ARE4. Taken together, our data demonstrates that Nrf2 regulates, in part, the expression of the rat Gclc gene through ARE4. Having identified the Gclc-AREs in the rat we sought to describe the molecular consequence of the age-related decrement of Nrf2 in hepatocytes isolated from young and old rats. ChIPs and reporter assays (ARE1-4) were used to investigate known ARE-binding transcription factors and the ARE mediated enhancement of Gclc transcription. We identified a decline in Nrf2 occupancy of ARE4 (40%) and a loss of transcriptional activity (70%; P < 0.05), consistent with the loss in Gclc levels. In addition, hepatic chromatin from old rat samples demonstrated ARE4 enrichment of the transcriptional repressor Bach1, and a loss of the histone acetyltransferase CREB-Binding Protein (CBP). These results demonstrate that the active Gclc transcriptional complex is remodeled into a repressive motif in the liver of old rats. Furthermore, ChIPs identified that Nrf2 binds ARE2 in liver lysate isolated from old rats but not young. In agreement with this finding, results from luciferase reporter assays suggest that ARE2 facilitates an Nrf2-dependent enhancement of Gclc expression in the old. Thus, a promoter switching mechanism may occur with age. In summary, we have identified key mechanisms of how the age-related decrement in Nrf2 protein levels is controlled and also gathered preliminary evidence that a pro-inflammatory state may contribute the loss of Nrf2 synthesis via increased miR levels. Finally, we have characterized the consequences of the loss of Nrf2 to GSH synthesis as an example of age-related impairment of cellular stress response. Title: Age-related loss of Nrf2, a novel mechanism for the potential attenuation of xenobiotic detoxification capacity Author: Smith, Eric Jonathan Nuclear Factor, Erythroid Derived 2, Like 2 (NFE2L2 or Nrf2) is the primary transcription factor in cellular defense against oxidative and xenobiotic stresses in higher eukaryotes. This basic leucine zipper transcription factor regulates over 200 antioxidant, detoxification, and lipid metabolizing genes by binding to the Antioxidant Response Element (ARE; a cis-acting element) as a transcription enhancer. Our group, and others, have identified that the nuclear steady state levels of this highly inducible transcription factor declines with age which coincides with decreased expression of many ARE regulated genes. To elucidate the mechanism(s) involved in lowered Nrf2 levels we used hepatocytes isolated from young and old rats as a relevant cellular model that maintains the aging phenotype with respect to Nrf2 levels. Our results show that steady state Nrf2 levels decline by ~40% with age (N=4, p<0.05), which led us to investigate the multifaceted regulation of Nrf2 homeostasis. Specifically, analysis of Nrf2 mRNA levels, and the rate of Nrf2 protein turnover and translation were investigated. Surprisingly, Keap1-mediated degradation of Nrf2, its primary negative regulator, did not account for the age-related Nrf2 decline, nor did mRNA levels change with age. Rather, Nrf2 protein synthesis declines 5.3-fold with age (N=3, p<0.05). Furthermore, we identify that rno-miR-146a, a key inflammation regulating miRNA, both inhibits Nrf2 translation and increases significantly with age. Taken together, our data suggest that the age-related loss of Nrf2 stems from the loss of its translation and may be mediated through miR regulation. Our lab previously demonstrated in rats, that the age-related loss of Nrf2 consequentially attenuates synthesis and steady state levels of liver glutathione (GSH) synthesis and manifests as a diminished level of GSH. This antioxidant is the most abundant non-protein thiol in most cells and is pivotal for the detoxification of many xenobiotics. The rate-limiting enzyme in GSH synthesis, γ-glutamyl-cysteine ligase (Gcl), is composed of a catalytic (Gclc), and a modulatory (Gclm) subunit. In mice and humans, it is established that Nrf2, through the ARE, regulates Gclc expression. However, this had not been established in rats. From a bioinformatics analysis of the 5’ upstream sequence of the rat Gclc gene, we identified 3 putative AREs (ARE1, ARE3, and ARE4), and one cis-element containing the core but not the flanking nucleotides of the ARE (ARE2). Luciferase reporter plasmids containing each individual ARE were transfected into H4IIE rat hepatoma cells to test for ARE activity. Only one, designated “ARE4”, produced appreciable luciferase activity and was dependent on Nrf2 expression, suggesting that this ARE is a “true” enhancer element. Chromatin immunoprecipitation (ChIP) and qPCR identified that Nrf2 binds ARE4 but not ARE1-3. Further ChIP analysis identified that known partner transcription factors of Nrf2 (small maf, c-Jun and c-Fos) were also bound to ARE4. Taken together, our data demonstrates that Nrf2 regulates, in part, the expression of the rat Gclc gene through ARE4. Having identified the Gclc-AREs in the rat we sought to describe the molecular consequence of the age-related decrement of Nrf2 in hepatocytes isolated from young and old rats. ChIPs and reporter assays (ARE1-4) were used to investigate known ARE-binding transcription factors and the ARE mediated enhancement of Gclc transcription. We identified a decline in Nrf2 occupancy of ARE4 (40%) and a loss of transcriptional activity (70%; P < 0.05), consistent with the loss in Gclc levels. In addition, hepatic chromatin from old rat samples demonstrated ARE4 enrichment of the transcriptional repressor Bach1, and a loss of the histone acetyltransferase CREB-Binding Protein (CBP). These results demonstrate that the active Gclc transcriptional complex is remodeled into a repressive motif in the liver of old rats. Furthermore, ChIPs identified that Nrf2 binds ARE2 in liver lysate isolated from old rats but not young. In agreement with this finding, results from luciferase reporter assays suggest that ARE2 facilitates an Nrf2-dependent enhancement of Gclc expression in the old. Thus, a promoter switching mechanism may occur with age. In summary, we have identified key mechanisms of how the age-related decrement in Nrf2 protein levels is controlled and also gathered preliminary evidence that a pro-inflammatory state may contribute the loss of Nrf2 synthesis via increased miR levels. Finally, we have characterized the consequences of the loss of Nrf2 to GSH synthesis as an example of age-related impairment of cellular stress response. Close

• 92. [Article] Families & aging : a guide to legal concerns

  Revised July 1988. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Families & aging : a guide to legal concerns Author: Schmall, Vicki L., Oregon State University. Extension Service Revised July 1988. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Families & aging : a guide to legal concerns Author: Schmall, Vicki L., Oregon State University. Extension Service Revised July 1988. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 93. [Article] Families & aging : a guide to legal concerns

  Published July 1985. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Families & aging : a guide to legal concerns Author: Schmall, Vicki L., Oregon State University. Extension Service Published July 1985. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Families & aging : a guide to legal concerns Author: Schmall, Vicki L., Oregon State University. Extension Service Published July 1985. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 94. [Article] Simulation of cattle cycle demography: cohort analysis of recruitment and culling decisions in the national beef cow herd

  This study expresses the hypothesis that historical patterns of national beef cow herd accumulation and liquidations (the cattle cycle) have been related to investment incentive differences across cow ...

  Citation × Citation Citation Abstract Copy Title: Simulation of cattle cycle demography: cohort analysis of recruitment and culling decisions in the national beef cow herd Author: Nordblom, Thomas L. This study expresses the hypothesis that historical patterns of national beef cow herd accumulation and liquidations (the cattle cycle) have been related to investment incentive differences across cow ages through time, resulting each year in changes in herd age structure, performance and potentials for adjustment in subsequent years. A review of national cattle cycle literature reveals the common assumption of variable heifer recruitment levels through time to the mature cow herd. A review of firm level cattle cycle stategy studies shows that most which considered heterogeneous herds (distinguishing performance by cow age) ironically assumed constant recruitment in proportion to cow numbers. Farmer interviews indicated that heifer recruitment may vary widely in proportion to cow numbers from year to year and that there are strong tendencies to cull non-pregnant and unsound cows from the herd at any age. The present study assumes both variable recruitment and age heterogenity. A search and synthesis of the biological literature allowed expression of economically important attributes as point estimates from continuous functions of cow age. These attributes are conception rates, health rates, cow survival rates, cull cow body weights, calf survival rates and weaning weights. Based on these biological parameters, and on the assumption that non-pregnant and unsound cows would be culled, retainment and culling rates are defined as management expectation parameters. These biological and expectation parameters are the building blocks of a simulation model designed to make value comparisons between cows of different ages and pregnancy status and to trace out changes in the national cow herd age structure through time. A budget generator produces estimates of expected net annual revenues for each of the 26 discrete age and pregnancy classes of heifers and cows, in each year from 1950 through 1978, based on exogenous price and cost series. These estimates are used to project the present values of expected future net revenues for each class of breeding animals. The ratio of future breeding value to present cull slaughter value is calculated for each of the 26 classes, each year. These V-ratios, in turn, are decision variables for determining the proportions of animals in each class to be retained in the herd, simulated by a national beef cow demography model. Annual summations from the demography model are compared with objective historical series of January 1 inventories of beef cows and replacement heifers, and annual numbers of cull cows slaughtered and beef calves born. The model's simplicity, ignoring related livestock sectors, is one of its significant features. With its few exogenous price and cost variables, simple biological relationships and management assumptions, the model is able to track the historical numbers of beef cows and calves born quite well. Mean proportional absolute deviations (MPAD) of the simulated series from the objective historical series were computed in addition to simple correlation coefficients and Theil's coefficients of inequality. In a display run, the tracking behavior of the model was best for cow inventories and calves born, and worst for heifer recruitment and cull cows, with MPAD's of .029, .036, .172, and .261, respectively. Theil's coefficients of inequality were .405, .587, .962, and .842, respectively. In an alternative run, with parameters set to reflect the assumption that all cows have the same performance characteristics across ages, the tracking behavior of the model was in several aspects about as good as the display run. Thus, the null hypothesis that performance differences across cow ages are of no importance in explaining investment behavior could not be rejected. Simulated national beef cow herd age structure changes through cattle cycles are shown from 1950 through 1978. Title: Simulation of cattle cycle demography: cohort analysis of recruitment and culling decisions in the national beef cow herd Author: Nordblom, Thomas L. This study expresses the hypothesis that historical patterns of national beef cow herd accumulation and liquidations (the cattle cycle) have been related to investment incentive differences across cow ages through time, resulting each year in changes in herd age structure, performance and potentials for adjustment in subsequent years. A review of national cattle cycle literature reveals the common assumption of variable heifer recruitment levels through time to the mature cow herd. A review of firm level cattle cycle stategy studies shows that most which considered heterogeneous herds (distinguishing performance by cow age) ironically assumed constant recruitment in proportion to cow numbers. Farmer interviews indicated that heifer recruitment may vary widely in proportion to cow numbers from year to year and that there are strong tendencies to cull non-pregnant and unsound cows from the herd at any age. The present study assumes both variable recruitment and age heterogenity. A search and synthesis of the biological literature allowed expression of economically important attributes as point estimates from continuous functions of cow age. These attributes are conception rates, health rates, cow survival rates, cull cow body weights, calf survival rates and weaning weights. Based on these biological parameters, and on the assumption that non-pregnant and unsound cows would be culled, retainment and culling rates are defined as management expectation parameters. These biological and expectation parameters are the building blocks of a simulation model designed to make value comparisons between cows of different ages and pregnancy status and to trace out changes in the national cow herd age structure through time. A budget generator produces estimates of expected net annual revenues for each of the 26 discrete age and pregnancy classes of heifers and cows, in each year from 1950 through 1978, based on exogenous price and cost series. These estimates are used to project the present values of expected future net revenues for each class of breeding animals. The ratio of future breeding value to present cull slaughter value is calculated for each of the 26 classes, each year. These V-ratios, in turn, are decision variables for determining the proportions of animals in each class to be retained in the herd, simulated by a national beef cow demography model. Annual summations from the demography model are compared with objective historical series of January 1 inventories of beef cows and replacement heifers, and annual numbers of cull cows slaughtered and beef calves born. The model's simplicity, ignoring related livestock sectors, is one of its significant features. With its few exogenous price and cost variables, simple biological relationships and management assumptions, the model is able to track the historical numbers of beef cows and calves born quite well. Mean proportional absolute deviations (MPAD) of the simulated series from the objective historical series were computed in addition to simple correlation coefficients and Theil's coefficients of inequality. In a display run, the tracking behavior of the model was best for cow inventories and calves born, and worst for heifer recruitment and cull cows, with MPAD's of .029, .036, .172, and .261, respectively. Theil's coefficients of inequality were .405, .587, .962, and .842, respectively. In an alternative run, with parameters set to reflect the assumption that all cows have the same performance characteristics across ages, the tracking behavior of the model was in several aspects about as good as the display run. Thus, the null hypothesis that performance differences across cow ages are of no importance in explaining investment behavior could not be rejected. Simulated national beef cow herd age structure changes through cattle cycles are shown from 1950 through 1978. Close

• 95. [Article] Changes in gene expression related to the decline of the aging immune system

  In this study, the gene expression levels between 6 month old mice and 26 month old mice were compared. The purpose of this research was to identify genes that are differentially regulated due to aging. ...

  Citation × Citation Citation Abstract Copy Title: Changes in gene expression related to the decline of the aging immune system Author: Gombart, Adrian F., Tran, Jenny K. In this study, the gene expression levels between 6 month old mice and 26 month old mice were compared. The purpose of this research was to identify genes that are differentially regulated due to aging. The results showed 148 significantly differentiated genes in the analysis of a total of 44,170 genes with 16 genes found to be related to immunity and inflammation. Title: Changes in gene expression related to the decline of the aging immune system Author: Gombart, Adrian F., Tran, Jenny K. In this study, the gene expression levels between 6 month old mice and 26 month old mice were compared. The purpose of this research was to identify genes that are differentially regulated due to aging. The results showed 148 significantly differentiated genes in the analysis of a total of 44,170 genes with 16 genes found to be related to immunity and inflammation. Close

• 96. [Article] Influence of marine environment on age and size at maturity, growth, and abundance of chum salmon, Ohcorhynchus keta (Walbaum), from Olsen Creek, Prince William Sound, Alaska

  Effects of the marine environment on age and size at maturity, early marine growth, and abundance of chum salmon, Oncorhynchus keta, were studied at Olsen Creek during 1959-77. Chum salmon returned to ...

  Citation × Citation Citation Abstract Copy Title: Influence of marine environment on age and size at maturity, growth, and abundance of chum salmon, Ohcorhynchus keta (Walbaum), from Olsen Creek, Prince William Sound, Alaska Author: Helle, John H. Effects of the marine environment on age and size at maturity, early marine growth, and abundance of chum salmon, Oncorhynchus keta, were studied at Olsen Creek during 1959-77. Chum salmon returned to Olsen Creek as predominately 3-, 4-, and 5-year fish; however, age composition varied from year to year. The mean age composition for the brood years 1956-72 for males was 15%, 66%, and 19% for 3-, 4-, and 5-year fish, respectively. Mean age composition for females of the same broods showed slightly higher percentages of older fish: 9%, 67%, and 23% for 3-, 4-, and 5-year fish, respectively. Some 6-year chum salmon returned to Olsen Creek between 1968 and 1975; but, only in 1973 did the number of 6-year fish (3%) represent more than 1% of the returns. Population sizes tended to be larger during these years, and mean age increased as the number of fish in a brood increased. Intraseasonally, age of new chum salmon spawners at Olsen Creek decreased as the season progressed. Mean size of older spawners was greater than the mean size of younger spawners; but, the ranges in size of the three age groups overlap each other so size is not a good criterion for estimating age of chum salmon. Measurement of circuli and distances on adult scales were used to estimate growth of chum salmon during their first two years of marine life. Both number of circuli and distances on scales of juvenile chum salmon after their first summer in Prince William Sound were shown to be related to length of the fish. Growth during the first season at sea was not related to age at maturity; however, amount of growth acquired during the second marine season was negatively related to age at maturity. Growth during the first summer at sea was related to sea surface temperatures and marine weather parameters in Prince William Sound and in the northern Gulf of Alaska. Location of chum salmon from Olsen Creek during their second year at sea is unknown. Fluctuations in size (length) at maturity were more similar between fish from different broods returning during the same year than they were for fish that matured at different ages from the same broods. Length at maturity was related to marine weather factors during their last summer at sea in the northern Gulf of Alaska and Prince William Sound. Length at maturity was also related to mean summer sea surface temperature in Prince William Sound during the year of return. Total survival of each brood was estimated from the ratio of number of progeny (returns) to number of parents (spawners). No direct relationships were found between survival and growth during the first or second season in the sea, sea surface temperatures, or upwelling indices along the coast. However, a highly significant relationship was found between the survival of progeny and mean length of the parents. Title: Influence of marine environment on age and size at maturity, growth, and abundance of chum salmon, Ohcorhynchus keta (Walbaum), from Olsen Creek, Prince William Sound, Alaska Author: Helle, John H. Effects of the marine environment on age and size at maturity, early marine growth, and abundance of chum salmon, Oncorhynchus keta, were studied at Olsen Creek during 1959-77. Chum salmon returned to Olsen Creek as predominately 3-, 4-, and 5-year fish; however, age composition varied from year to year. The mean age composition for the brood years 1956-72 for males was 15%, 66%, and 19% for 3-, 4-, and 5-year fish, respectively. Mean age composition for females of the same broods showed slightly higher percentages of older fish: 9%, 67%, and 23% for 3-, 4-, and 5-year fish, respectively. Some 6-year chum salmon returned to Olsen Creek between 1968 and 1975; but, only in 1973 did the number of 6-year fish (3%) represent more than 1% of the returns. Population sizes tended to be larger during these years, and mean age increased as the number of fish in a brood increased. Intraseasonally, age of new chum salmon spawners at Olsen Creek decreased as the season progressed. Mean size of older spawners was greater than the mean size of younger spawners; but, the ranges in size of the three age groups overlap each other so size is not a good criterion for estimating age of chum salmon. Measurement of circuli and distances on adult scales were used to estimate growth of chum salmon during their first two years of marine life. Both number of circuli and distances on scales of juvenile chum salmon after their first summer in Prince William Sound were shown to be related to length of the fish. Growth during the first season at sea was not related to age at maturity; however, amount of growth acquired during the second marine season was negatively related to age at maturity. Growth during the first summer at sea was related to sea surface temperatures and marine weather parameters in Prince William Sound and in the northern Gulf of Alaska. Location of chum salmon from Olsen Creek during their second year at sea is unknown. Fluctuations in size (length) at maturity were more similar between fish from different broods returning during the same year than they were for fish that matured at different ages from the same broods. Length at maturity was related to marine weather factors during their last summer at sea in the northern Gulf of Alaska and Prince William Sound. Length at maturity was also related to mean summer sea surface temperature in Prince William Sound during the year of return. Total survival of each brood was estimated from the ratio of number of progeny (returns) to number of parents (spawners). No direct relationships were found between survival and growth during the first or second season in the sea, sea surface temperatures, or upwelling indices along the coast. However, a highly significant relationship was found between the survival of progeny and mean length of the parents. Close

• 97. [Article] Estimation of Population Age Structure, Detection Probability, and Density of Red Tree Voles in Oregon

  Red tree voles (Arborimus longicaudus) are a unique species of Arvicoline rodent found in western Oregon and northwest California. Their preferred habitat is mature and old-growth coniferous forest dominated ...

  Citation × Citation Citation Abstract Copy Title: Estimation of Population Age Structure, Detection Probability, and Density of Red Tree Voles in Oregon Author: Marks-Fife, Chad A. Red tree voles (Arborimus longicaudus) are a unique species of Arvicoline rodent found in western Oregon and northwest California. Their preferred habitat is mature and old-growth coniferous forest dominated by Douglas-fir (Pseudotsuga menziesii). Tree voles are an important prey item for northern spotted owls and many other predators, but are extremely difficult to sample. As a result, little is known about their abundance or population dynamics. We used several methods to describe tree vole detectability, density, and population age structure. We verified a relationship between molar tooth development and age in red tree voles, allowing us to estimate the age of voles recovered in pellets regurgitated by spotted owls in Oregon. We found that the age distribution of tree voles in spotted owl pellets varied from year to year but not from region to region within the species range. We found evidence for a positive relationship between annual precipitation and the proportion of juvenile tree voles in owl pellets on one of two study areas. We conducted modified line-transect surveys at 31 locations representing three forest stand age classes (young, mature, old) in the Oregon Coast Range to visually detect potential red tree vole nests. We climbed trees where potential nests were detected from the ground in order to determine the species and the occupancy status of nests. We used the transect and climbing data and distance sampling techniques to estimate detection probabilities and density of active tree vole nest trees in relation to forest age class. Our surveys suggested that density of tree vole nest trees increased with forest age, whereas detection probability of nest trees decreased with forest age. Regardless of forest age, mean detection probability of nest trees was low (< 30%). We used estimates of nest tree density on our study area to estimate the minimum density of adult tree voles (~1.91/ha) and the density of individual tree vole home ranges (~4.2/ha). These estimates of detection probability and density suggest that only a small proportion of nest trees are detected and buffered against disturbance using methods described in the survey protocol used by federal agencies in Oregon and California. We recommend methods to improve detection rates of nest trees, including application of our density estimates to occupied stands, modification of stand-specific data using our estimates of detection probability, performing full-tree nest searches in every tree climbed, performing a 100 m search radius around confirmed nest trees, and targeting larger-than-average trees (with respect to stand-specific data) for spot searches. Title: Estimation of Population Age Structure, Detection Probability, and Density of Red Tree Voles in Oregon Author: Marks-Fife, Chad A. Red tree voles (Arborimus longicaudus) are a unique species of Arvicoline rodent found in western Oregon and northwest California. Their preferred habitat is mature and old-growth coniferous forest dominated by Douglas-fir (Pseudotsuga menziesii). Tree voles are an important prey item for northern spotted owls and many other predators, but are extremely difficult to sample. As a result, little is known about their abundance or population dynamics. We used several methods to describe tree vole detectability, density, and population age structure. We verified a relationship between molar tooth development and age in red tree voles, allowing us to estimate the age of voles recovered in pellets regurgitated by spotted owls in Oregon. We found that the age distribution of tree voles in spotted owl pellets varied from year to year but not from region to region within the species range. We found evidence for a positive relationship between annual precipitation and the proportion of juvenile tree voles in owl pellets on one of two study areas. We conducted modified line-transect surveys at 31 locations representing three forest stand age classes (young, mature, old) in the Oregon Coast Range to visually detect potential red tree vole nests. We climbed trees where potential nests were detected from the ground in order to determine the species and the occupancy status of nests. We used the transect and climbing data and distance sampling techniques to estimate detection probabilities and density of active tree vole nest trees in relation to forest age class. Our surveys suggested that density of tree vole nest trees increased with forest age, whereas detection probability of nest trees decreased with forest age. Regardless of forest age, mean detection probability of nest trees was low (< 30%). We used estimates of nest tree density on our study area to estimate the minimum density of adult tree voles (~1.91/ha) and the density of individual tree vole home ranges (~4.2/ha). These estimates of detection probability and density suggest that only a small proportion of nest trees are detected and buffered against disturbance using methods described in the survey protocol used by federal agencies in Oregon and California. We recommend methods to improve detection rates of nest trees, including application of our density estimates to occupied stands, modification of stand-specific data using our estimates of detection probability, performing full-tree nest searches in every tree climbed, performing a 100 m search radius around confirmed nest trees, and targeting larger-than-average trees (with respect to stand-specific data) for spot searches. Close

• 98. [Article] Timescales of large silicic magma systems : implications from accessory minerals in Pleistocene lavas of the Altiplano-Puna Volcanic Complex, central Andes

  Constraining the development, evolution, and timescales of large silicic magma systems is important to understanding the development of granite batholiths, the relationships between volcanoes and their ...

  Citation × Citation Citation Abstract Copy Title: Timescales of large silicic magma systems : implications from accessory minerals in Pleistocene lavas of the Altiplano-Puna Volcanic Complex, central Andes Author: Tierney, Casey R. Constraining the development, evolution, and timescales of large silicic magma systems is important to understanding the development of granite batholiths, the relationships between volcanoes and their plutonic underpinnings, and the development of the continental crust. The ignimbrite flare up that produced the Altiplano-Puna Volcanic Complex of the Central Andes is characterized by episodic volcanism over a ~11 Ma time-span that climaxed about 4 Ma. Since peak activity, the temporal and spatial record of volcanism suggests a waning of the system with only one other supervolcanic eruption at 2.6 Ma. The most recent phase of volcanism from the APVC comprises a series of late Pleistocene domes that share a general petrochemical resemblance to the ignimbrites. New U-Th/U-Pb data on zircons and high precision 40Ar/39Ar age determinations reveal that these effusive eruptions represent a temporally coherent magmatic episode. The five largest domes (Chao, Chillahuita, Chanka, Chascon-Runtu Jarita, and Tocopuri) have a combined volume >40 km³, and are distributed over a roughly elliptical area of almost 2000km² centered at 22°S 68°W. They are crystal rich (>50%) dacites to rhyolites. ⁴⁰Ar/³⁹Ar ages from biotite reveals eruption ages from 108±6 to 120±5 ka while more accurate sanidine for some of the domes reveal eruption ages from 87±4 to 97±2 ka. SIMS U-series crystallization ages from the rims of 215 zircon crystals from the domes show a similar age spectra from dome to dome, with common peaks in zircon ages at ~100ka and ~220ka. Furthermore, the ages reveal a fairly continuous spread of ages from near eruption to >300ka indicating that the residence time of this magma body was likely over a similar time interval. Ubiquitous andesitic inclusions evidence a vital role for recharge in sustaining and maybe eventual eruption of these magmas. Lastly, the interiors of crystals with rim U-Th secular equilibrium ages were re-analyzed and have yielded U-Pb ages of up to 3.5 Ma. The presence of these older interiors suggests that the source region of these magmas retained a record of an earlier history dating back to the last supervolcanic eruption in the region from the nearby Pastos Grandes caldera. This suggests that the thermal history of the system precluded complete resorption of antecrysts. The volcanological, petrological, temporal and spatial coherence of this series of eruptions combined with the similar ⁴⁰Ar/³⁹Ar and zircon age spectra argue for a long-lived and unitary magma chamber revealing perhaps the waning of this major continental magma system. Title: Timescales of large silicic magma systems : implications from accessory minerals in Pleistocene lavas of the Altiplano-Puna Volcanic Complex, central Andes Author: Tierney, Casey R. Constraining the development, evolution, and timescales of large silicic magma systems is important to understanding the development of granite batholiths, the relationships between volcanoes and their plutonic underpinnings, and the development of the continental crust. The ignimbrite flare up that produced the Altiplano-Puna Volcanic Complex of the Central Andes is characterized by episodic volcanism over a ~11 Ma time-span that climaxed about 4 Ma. Since peak activity, the temporal and spatial record of volcanism suggests a waning of the system with only one other supervolcanic eruption at 2.6 Ma. The most recent phase of volcanism from the APVC comprises a series of late Pleistocene domes that share a general petrochemical resemblance to the ignimbrites. New U-Th/U-Pb data on zircons and high precision 40Ar/39Ar age determinations reveal that these effusive eruptions represent a temporally coherent magmatic episode. The five largest domes (Chao, Chillahuita, Chanka, Chascon-Runtu Jarita, and Tocopuri) have a combined volume >40 km³, and are distributed over a roughly elliptical area of almost 2000km² centered at 22°S 68°W. They are crystal rich (>50%) dacites to rhyolites. ⁴⁰Ar/³⁹Ar ages from biotite reveals eruption ages from 108±6 to 120±5 ka while more accurate sanidine for some of the domes reveal eruption ages from 87±4 to 97±2 ka. SIMS U-series crystallization ages from the rims of 215 zircon crystals from the domes show a similar age spectra from dome to dome, with common peaks in zircon ages at ~100ka and ~220ka. Furthermore, the ages reveal a fairly continuous spread of ages from near eruption to >300ka indicating that the residence time of this magma body was likely over a similar time interval. Ubiquitous andesitic inclusions evidence a vital role for recharge in sustaining and maybe eventual eruption of these magmas. Lastly, the interiors of crystals with rim U-Th secular equilibrium ages were re-analyzed and have yielded U-Pb ages of up to 3.5 Ma. The presence of these older interiors suggests that the source region of these magmas retained a record of an earlier history dating back to the last supervolcanic eruption in the region from the nearby Pastos Grandes caldera. This suggests that the thermal history of the system precluded complete resorption of antecrysts. The volcanological, petrological, temporal and spatial coherence of this series of eruptions combined with the similar ⁴⁰Ar/³⁹Ar and zircon age spectra argue for a long-lived and unitary magma chamber revealing perhaps the waning of this major continental magma system. Close

• 99. [Article] An assessment of the reproductive cycle in black rockfish, Sebastes melanops (Girard, 1856) on the central Oregon Coast : a blood plasma protein and sex steroid used as potential indicators of sex and stage of gonadal maturity

  Because of large declines in abundance of many Eastern Pacific rockfish populations (Genus Sebastes), there has been an increasing effort to improve our understanding of the role of spawning population ...

  Citation × Citation Citation Abstract Copy Title: An assessment of the reproductive cycle in black rockfish, Sebastes melanops (Girard, 1856) on the central Oregon Coast : a blood plasma protein and sex steroid used as potential indicators of sex and stage of gonadal maturity Author: Martin-Mills, Brooke E. Because of large declines in abundance of many Eastern Pacific rockfish populations (Genus Sebastes), there has been an increasing effort to improve our understanding of the role of spawning population characteristics and individual reproductive success in recruitment variability and population dynamics. Current methods for assessing sex and maturational status in rockfishes are lethal, so fishery managers would benefit from a non-lethal method to assess the reproductive potential of rockfish populations. I developed a biochemical assay to determine sex and stage of female maturity in black rockfish (Sebastes melanops) using a blood plasma indicator vitellogenin (VTG). The specific objectives of this research were to: 1) describe the annual hormonal and gonadal changes associated with reproduction and 2) describe the timing of reproduction in female black rockfish of different age classes. Estradiol-17β (E2) and VTG concentrations were compared with histologically determined ovarian stages of female maturity (i.e. pre-vitellogenic, early vitellogenic, mid-vitellogenic, post-vitellogenic, oocyte maturation, and post-spawned) from 325 female black rockfish sampled by hook-and-line from the central Oregon coast from September 2003 to January 2005. I also measured E2 and VTG in male fish from the same time period. VTG concentrations detected in field-collected blood samples reflected the seasonal cycle reported in previous studies. Mean concentrations of VTG in mid-vitellogenic, post-vitellogenic, and females undergoing oocyte maturation can be used to distinguish between pre-vitellogenic females and early vitellogenic females during the spawning season (P<0.05). Females can be distinguished from males based on VTG concentrations (P<0.0001), with the exception of pre-vitellogenic and post-spawned females (immature fish and mature female fish in non-reproductive summer months). Mean E2 concentrations were not as accurate for identification of sex and each individual stage of female maturity, although mid-vitellogenic and post-vitellogenic females had significantly higher concentrations of E2 than pre-vitellogenic females (P<0.05). Mean concentrations of E2 in mid-vitellogenic females, post-vitellogenic females, and females undergoing oocyte maturation were higher than in males (P<0.0001). A Discriminant Function Analysis (DFA) identified VTG as the best predictor for predicting sex from plasma samples, with, 82% of fish correctly classified by sex. Of the 100 females and 30 males examined, 68% of females and 97% of males were correctly classified. The DFA choose plasma VTG, total length, and weight as the best predictors of stage of maturity in females and some stages could be distinguished from each other with ≈65% accuracy. The second goal of this research was to use the biochemical assay to investigate the differences in timing of reproduction in young and older females in this species. In the fall (September-November) females age 5-8 made up 43 % of early and mid-vitellogenic (stage 3 and 4) females, where as, age 9+ females made up 100% of the females that were post-vitellogenic (stage 5) and undergoing oocyte maturation (stage 6). Females’ ages 6-8 captured in the winter months (December-February) made up 90% of the mid- and late vitellogenic (stage 4 and 5) and 100% of post-spawned (stages 7 and 8) fish. In the spring (March-May) 40% of post-spawned females were age 8 and 60% were age 9+. These results suggest that older females have more of a protracted spawning period than younger fish. Females from all age categories showed a similar trend of hormone and protein cycling. Concentrations of E2 and VTG increased throughout September-December, peaked in February, decreased and remained low until the end of August. Concentrations of E2 for early vitellogenic (stage 3) fish of the age 9+ were significantly higher than in females ages 3-5. Females’ age 9+ undergoing oocyte maturation (stage 6) had higher concentrations of E2 than females ages 6-8. Early vitellogenic (stage 3) and mid-vitellogenic (stage 4) females ages 6-8 and 9+ had higher concentrations of VTG than in females ages 3-5. Small samples sizes were prohibitive in comparing VTG and E2 concentrations between all age groups and stages of maturity, and I did not find conclusive evidence of differences in seasonal VTG or E2 levels among age groups. Potentially, this newly developed vitellogenin assay may be used for other rockfish species, providing a non-lethal assessment tool to differentiate between sex and stage of maturity in females. Title: An assessment of the reproductive cycle in black rockfish, Sebastes melanops (Girard, 1856) on the central Oregon Coast : a blood plasma protein and sex steroid used as potential indicators of sex and stage of gonadal maturity Author: Martin-Mills, Brooke E. Because of large declines in abundance of many Eastern Pacific rockfish populations (Genus Sebastes), there has been an increasing effort to improve our understanding of the role of spawning population characteristics and individual reproductive success in recruitment variability and population dynamics. Current methods for assessing sex and maturational status in rockfishes are lethal, so fishery managers would benefit from a non-lethal method to assess the reproductive potential of rockfish populations. I developed a biochemical assay to determine sex and stage of female maturity in black rockfish (Sebastes melanops) using a blood plasma indicator vitellogenin (VTG). The specific objectives of this research were to: 1) describe the annual hormonal and gonadal changes associated with reproduction and 2) describe the timing of reproduction in female black rockfish of different age classes. Estradiol-17β (E2) and VTG concentrations were compared with histologically determined ovarian stages of female maturity (i.e. pre-vitellogenic, early vitellogenic, mid-vitellogenic, post-vitellogenic, oocyte maturation, and post-spawned) from 325 female black rockfish sampled by hook-and-line from the central Oregon coast from September 2003 to January 2005. I also measured E2 and VTG in male fish from the same time period. VTG concentrations detected in field-collected blood samples reflected the seasonal cycle reported in previous studies. Mean concentrations of VTG in mid-vitellogenic, post-vitellogenic, and females undergoing oocyte maturation can be used to distinguish between pre-vitellogenic females and early vitellogenic females during the spawning season (P<0.05). Females can be distinguished from males based on VTG concentrations (P<0.0001), with the exception of pre-vitellogenic and post-spawned females (immature fish and mature female fish in non-reproductive summer months). Mean E2 concentrations were not as accurate for identification of sex and each individual stage of female maturity, although mid-vitellogenic and post-vitellogenic females had significantly higher concentrations of E2 than pre-vitellogenic females (P<0.05). Mean concentrations of E2 in mid-vitellogenic females, post-vitellogenic females, and females undergoing oocyte maturation were higher than in males (P<0.0001). A Discriminant Function Analysis (DFA) identified VTG as the best predictor for predicting sex from plasma samples, with, 82% of fish correctly classified by sex. Of the 100 females and 30 males examined, 68% of females and 97% of males were correctly classified. The DFA choose plasma VTG, total length, and weight as the best predictors of stage of maturity in females and some stages could be distinguished from each other with ≈65% accuracy. The second goal of this research was to use the biochemical assay to investigate the differences in timing of reproduction in young and older females in this species. In the fall (September-November) females age 5-8 made up 43 % of early and mid-vitellogenic (stage 3 and 4) females, where as, age 9+ females made up 100% of the females that were post-vitellogenic (stage 5) and undergoing oocyte maturation (stage 6). Females’ ages 6-8 captured in the winter months (December-February) made up 90% of the mid- and late vitellogenic (stage 4 and 5) and 100% of post-spawned (stages 7 and 8) fish. In the spring (March-May) 40% of post-spawned females were age 8 and 60% were age 9+. These results suggest that older females have more of a protracted spawning period than younger fish. Females from all age categories showed a similar trend of hormone and protein cycling. Concentrations of E2 and VTG increased throughout September-December, peaked in February, decreased and remained low until the end of August. Concentrations of E2 for early vitellogenic (stage 3) fish of the age 9+ were significantly higher than in females ages 3-5. Females’ age 9+ undergoing oocyte maturation (stage 6) had higher concentrations of E2 than females ages 6-8. Early vitellogenic (stage 3) and mid-vitellogenic (stage 4) females ages 6-8 and 9+ had higher concentrations of VTG than in females ages 3-5. Small samples sizes were prohibitive in comparing VTG and E2 concentrations between all age groups and stages of maturity, and I did not find conclusive evidence of differences in seasonal VTG or E2 levels among age groups. Potentially, this newly developed vitellogenin assay may be used for other rockfish species, providing a non-lethal assessment tool to differentiate between sex and stage of maturity in females. Close

• 100. [Article] Retirement-age migration to and from Oregon : who is still on the Oregon Trail?

  Oregon, much like the nation, has historically had a paradoxical relationship to migration. Oregon is famous for the Lewis and Clark expedition and the Oregon Trail. It is, and always has been, greatly ...

  Citation × Citation Citation Abstract Copy Title: Retirement-age migration to and from Oregon : who is still on the Oregon Trail? Author: Gagnier, Cliff R. Oregon, much like the nation, has historically had a paradoxical relationship to migration. Oregon is famous for the Lewis and Clark expedition and the Oregon Trail. It is, and always has been, greatly affected and inspired by interstate migration yet each successive generation has been less than welcoming to further migration. Today, Oregon is a desirable destination for retirement-aged migrants for its scenic beauty and mild seasons. This essay will use census data from 2000 to describe the characteristics associated with retirement-age migrants to Oregon. Multinomial logistic regression analysis is used to compare retirement-aged Oregon in-migrants with Oregon non-movers, Oregon out-migrants and non-movers and out-migrants of the states from which in-migrants to Oregon originated. In three cases, the characteristics effecting the decision to migrate are determined by comparing a migrant group population with its respective non-mover population. This essay is a useful tool for those seeking to understand the characteristics important to retirement-age migration to Oregon as well as the factors influencing the migration decision. Title: Retirement-age migration to and from Oregon : who is still on the Oregon Trail? Author: Gagnier, Cliff R. Oregon, much like the nation, has historically had a paradoxical relationship to migration. Oregon is famous for the Lewis and Clark expedition and the Oregon Trail. It is, and always has been, greatly affected and inspired by interstate migration yet each successive generation has been less than welcoming to further migration. Today, Oregon is a desirable destination for retirement-aged migrants for its scenic beauty and mild seasons. This essay will use census data from 2000 to describe the characteristics associated with retirement-age migrants to Oregon. Multinomial logistic regression analysis is used to compare retirement-aged Oregon in-migrants with Oregon non-movers, Oregon out-migrants and non-movers and out-migrants of the states from which in-migrants to Oregon originated. In three cases, the characteristics effecting the decision to migrate are determined by comparing a migrant group population with its respective non-mover population. This essay is a useful tool for those seeking to understand the characteristics important to retirement-age migration to Oregon as well as the factors influencing the migration decision. Close