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• 41. [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

• 42. [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

• 43. [Article] Chronological Age, Mental Age and Socioeconomic Status Variance in Expressive Preposition Acquisition of Young Children

  The present study was designed to determine the ages at which a sample of children between eighteen and forty-two months verbally and correctly express the fourteen prepositions known to be acquired by ...

  Citation × Citation Citation Abstract Copy Title: Chronological Age, Mental Age and Socioeconomic Status Variance in Expressive Preposition Acquisition of Young Children Author: Heckel, Arthur J. Year: 1975 The present study was designed to determine the ages at which a sample of children between eighteen and forty-two months verbally and correctly express the fourteen prepositions known to be acquired by age four, using the Revised Expressive Preposition Test (REPT). The REPT was administered to sixty children chosen from day care centers and private homes within the metropolitan area of Portland, Oregon. Therewas no preference as to the sex, intelligence of the child or socio- economic status of the child's family. A statistical analysis was performed to determine the correlation between HEPT scores and the child's chronological age, mental age and the socioeconomic status of the child's family. Results show that expressive prepositions tend to be acquired at different age levels. Each age group tended to use a progressively greater number of the prepositions. None of the eighteen month olds used any of the prepositions. Only one-fourth of the twenty-four month olds used any of the prepositions. Half or more of the thirty month olds expressed the prepositions "under," "on," "in" and "up." Half or more of the thirty-six month olds expressed the prepositions "out of," "at," "in" and "up," but not "under" and "on." Half or more of the forty-two month olds expressed the prepositions "to, II, "out of," "under," "around," "at," "of," "with" and "up." One hundred per cent of the forty-two month olds also used the prepositions "in" and "on." The prepositions which were never expressed by 50 per cent of any of the children were "behind," "across," "off" and "by." A statistical analysis of the data revealed a moderate correlation between the children's REPT scores and their chronological ages (.68). Correlation coefficients indicated a high correlation between the children's REFT scores and their combined chronological and mental ages (.82). The children's SES scores did not correlate with REPT scores (1 per cent) when considered together with chronological and mental ages. Title: Chronological Age, Mental Age and Socioeconomic Status Variance in Expressive Preposition Acquisition of Young Children Author: Heckel, Arthur J. Year: 1975 The present study was designed to determine the ages at which a sample of children between eighteen and forty-two months verbally and correctly express the fourteen prepositions known to be acquired by age four, using the Revised Expressive Preposition Test (REPT). The REPT was administered to sixty children chosen from day care centers and private homes within the metropolitan area of Portland, Oregon. Therewas no preference as to the sex, intelligence of the child or socio- economic status of the child's family. A statistical analysis was performed to determine the correlation between HEPT scores and the child's chronological age, mental age and the socioeconomic status of the child's family. Results show that expressive prepositions tend to be acquired at different age levels. Each age group tended to use a progressively greater number of the prepositions. None of the eighteen month olds used any of the prepositions. Only one-fourth of the twenty-four month olds used any of the prepositions. Half or more of the thirty month olds expressed the prepositions "under," "on," "in" and "up." Half or more of the thirty-six month olds expressed the prepositions "out of," "at," "in" and "up," but not "under" and "on." Half or more of the forty-two month olds expressed the prepositions "to, II, "out of," "under," "around," "at," "of," "with" and "up." One hundred per cent of the forty-two month olds also used the prepositions "in" and "on." The prepositions which were never expressed by 50 per cent of any of the children were "behind," "across," "off" and "by." A statistical analysis of the data revealed a moderate correlation between the children's REPT scores and their chronological ages (.68). Correlation coefficients indicated a high correlation between the children's REFT scores and their combined chronological and mental ages (.82). The children's SES scores did not correlate with REPT scores (1 per cent) when considered together with chronological and mental ages. Close

• 44. [Article] The Mediating Effects of LMX on the Relationship Between Supervisor and Employee Age Differences, Satisfaction, and Retirement Intentions

  Increasing age heterogeneity within organizations is pressing researchers to better understand the effects of a multigenerational workforce, teams, and dyads. In response to this, the present research ...

  Citation × Citation Citation Abstract Copy Title: The Mediating Effects of LMX on the Relationship Between Supervisor and Employee Age Differences, Satisfaction, and Retirement Intentions Author: Pytlovany, Amy Christine Year: 2016 Increasing age heterogeneity within organizations is pressing researchers to better understand the effects of a multigenerational workforce, teams, and dyads. In response to this, the present research aimed to investigate the effect of employee and supervisor age (in)congruence in relation to job and life satisfaction, as well as retirement intentions, all mediated by leader-member exchange (LMX), using a time-lagged design. Two different theoretical foundations were investigated. Based on the relational demography literature, better outcomes were expected to be associated with age similarity. Theories about implicit expectations relating age and social role guided hypotheses suggesting that beyond just similarity or difference, the direction of age differences would matter. Based on traditional social assumptions that age is associated with experience and wisdom, it was expected that work outcomes would be better when the supervisor was older than the employee, and worse when the supervisor was younger than the employee. Results did not support any of the proposed hypotheses, with the exception of the established relationship between LMX and job satisfaction. However, response surface graphs and polynomial regression results directed post hoc analyses which did reveal a main effect of supervisor age on LMX and an indirect effect of supervisor age on Time 2 job satisfaction through Time 1 LMX. Employees in this sample reported higher quality LMX when supervisors were younger, regardless of employee age, and in turn employees with younger supervisors reported higher job satisfaction. These results and the trends depicted by response surface graphs are discussed in relation to implications for research and practice. Title: The Mediating Effects of LMX on the Relationship Between Supervisor and Employee Age Differences, Satisfaction, and Retirement Intentions Author: Pytlovany, Amy Christine Year: 2016 Increasing age heterogeneity within organizations is pressing researchers to better understand the effects of a multigenerational workforce, teams, and dyads. In response to this, the present research aimed to investigate the effect of employee and supervisor age (in)congruence in relation to job and life satisfaction, as well as retirement intentions, all mediated by leader-member exchange (LMX), using a time-lagged design. Two different theoretical foundations were investigated. Based on the relational demography literature, better outcomes were expected to be associated with age similarity. Theories about implicit expectations relating age and social role guided hypotheses suggesting that beyond just similarity or difference, the direction of age differences would matter. Based on traditional social assumptions that age is associated with experience and wisdom, it was expected that work outcomes would be better when the supervisor was older than the employee, and worse when the supervisor was younger than the employee. Results did not support any of the proposed hypotheses, with the exception of the established relationship between LMX and job satisfaction. However, response surface graphs and polynomial regression results directed post hoc analyses which did reveal a main effect of supervisor age on LMX and an indirect effect of supervisor age on Time 2 job satisfaction through Time 1 LMX. Employees in this sample reported higher quality LMX when supervisors were younger, regardless of employee age, and in turn employees with younger supervisors reported higher job satisfaction. These results and the trends depicted by response surface graphs are discussed in relation to implications for research and practice. Close

• 45. [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

• 46. [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

• 47. [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

• 48. [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

• 49. [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

• 50. [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