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• 41. [Article] The Historical, Political, Social, and Individual Factors That Have Influenced the Development of Aging and Disability Resource Centers and Options Counseling

  This thesis reports on the perspectives and experiences of policymakers, advocates, agency supervisors, and experts in the field of gerontology, about the development of Aging and Disability Resource Centers ...

  Citation × Citation Citation Abstract Copy Title: The Historical, Political, Social, and Individual Factors That Have Influenced the Development of Aging and Disability Resource Centers and Options Counseling Author: Elliott, Sheryl DeJoy Year: 2013 This thesis reports on the perspectives and experiences of policymakers, advocates, agency supervisors, and experts in the field of gerontology, about the development of Aging and Disability Resource Centers (ADRC) programs and Options Counseling (OC). By examining the foundations upon which ADRCs and OC are built, this study sought to inform future research about the effectiveness of existing practice, increase understanding of best practices, and clarify whether these emerging services are accomplishing original goals. ADRCs and OC intend to address long-term care issues and healthcare needs by providing a single entry point to the social service system. ADRCs offer information, assistance, and OC to people of all ages, incomes, and disabilities, and promote long-term care options that honor independence and respect for the needs and preferences of individuals, their families, and caregivers. They are the latest iteration of policymakers' efforts to provide affordable home-and community-based care for older persons and their caregivers. A total of fifteen qualitative interviews were conducted and analyzed using grounded theory methods. Key persons interviewed included experts in the area of aging, aging policy, and aging. Participants were recruited through referrals suggested by Portland State University's (PSU) Institute on Aging (IOA) staff. In addition, several key experts known to the researcher through affiliation with PSU's IOA agreed to be interviewed. Snowball sampling was then used to locate additional key experts. Interview participants were classified as advocates, state decision makers, policy makers, or academicians. Advocates included national and state directors of agencies that promote the development and management of effective services to aging adults. State decision makers included state directors, ADRC directors and supervisors, and program analysts. Policy makers interviewed were national program directors responsible for shaping the future of developing programs to assist older adults. Academicians who participated in the study have been instrumental in developing and researching practices that promote well-being for the aging and the aged. These key experts were selected based on their knowledge and ability to inform the strengths, weakness, and development of ADRCs and Options Counseling. Many have been instrumental in health and aging policy and service development and research, and possess insider knowledge not available to the general public regarding attitudes and interests motivating the actors. Findings indicate that ADRCs and OC are designed to manage within existing social service systems. They can benefit some individuals by providing more options and support in accessing public and private services. It remains to be seen whether they have the capacity to ameliorate some existing system-level problems. Findings highlight program strengths and weaknesses, sustainability issues, and policymakers, state decision makers', and providers' commitment to sustaining ADRCs and OC. Title: The Historical, Political, Social, and Individual Factors That Have Influenced the Development of Aging and Disability Resource Centers and Options Counseling Author: Elliott, Sheryl DeJoy Year: 2013 This thesis reports on the perspectives and experiences of policymakers, advocates, agency supervisors, and experts in the field of gerontology, about the development of Aging and Disability Resource Centers (ADRC) programs and Options Counseling (OC). By examining the foundations upon which ADRCs and OC are built, this study sought to inform future research about the effectiveness of existing practice, increase understanding of best practices, and clarify whether these emerging services are accomplishing original goals. ADRCs and OC intend to address long-term care issues and healthcare needs by providing a single entry point to the social service system. ADRCs offer information, assistance, and OC to people of all ages, incomes, and disabilities, and promote long-term care options that honor independence and respect for the needs and preferences of individuals, their families, and caregivers. They are the latest iteration of policymakers' efforts to provide affordable home-and community-based care for older persons and their caregivers. A total of fifteen qualitative interviews were conducted and analyzed using grounded theory methods. Key persons interviewed included experts in the area of aging, aging policy, and aging. Participants were recruited through referrals suggested by Portland State University's (PSU) Institute on Aging (IOA) staff. In addition, several key experts known to the researcher through affiliation with PSU's IOA agreed to be interviewed. Snowball sampling was then used to locate additional key experts. Interview participants were classified as advocates, state decision makers, policy makers, or academicians. Advocates included national and state directors of agencies that promote the development and management of effective services to aging adults. State decision makers included state directors, ADRC directors and supervisors, and program analysts. Policy makers interviewed were national program directors responsible for shaping the future of developing programs to assist older adults. Academicians who participated in the study have been instrumental in developing and researching practices that promote well-being for the aging and the aged. These key experts were selected based on their knowledge and ability to inform the strengths, weakness, and development of ADRCs and Options Counseling. Many have been instrumental in health and aging policy and service development and research, and possess insider knowledge not available to the general public regarding attitudes and interests motivating the actors. Findings indicate that ADRCs and OC are designed to manage within existing social service systems. They can benefit some individuals by providing more options and support in accessing public and private services. It remains to be seen whether they have the capacity to ameliorate some existing system-level problems. Findings highlight program strengths and weaknesses, sustainability issues, and policymakers, state decision makers', and providers' commitment to sustaining ADRCs and OC. Close

• 42. [Article] Ascorbic acid, lipid peroxidation, and aging

  The role of ascorbic acid with regard to lipid peroxidation and aging has been examined. A thorough literature analysis indicates that free radical-induced lipid peroxidation is a plausible biochemical ...

  Citation × Citation Citation Abstract Copy Title: Ascorbic acid, lipid peroxidation, and aging Author: Leibovitz, Brian Evan Year: 1979 The role of ascorbic acid with regard to lipid peroxidation and aging has been examined. A thorough literature analysis indicates that free radical-induced lipid peroxidation is a plausible biochemical explanation for aging. Lipid peroxidation causes cellular damage due to altered enzyme activities, error-prone nucleic acid metabolism, and membrane dysfunction, as well as the accumulation of aging pigments in the lysomes. Ascorbic acid, a water soluble free radical quencher, was examined with regard to carbon tetra-chloride-induced lipid peroxidation and in vivo aging. Carbon tetrachloride, a well-known free radical inducer, caused marked increases in the ration of oxidized/reduced vitamin C only in the organs which metabolize carbon tetrachloride to the free radical form. Vitamin C treatment, 250 mg% in the drinking water, reduced the extent of carbon tetrachloride=induced lipid peroxidation. Aging is associated with marked increases in the ration of oxidized/reduced vitamin C in all organs examined with the exception of thymus. In organs exposed to high oxygen tensions, or in those exposed to high levels of free radicals, the ration of oxidized/reduced vitamin C exceeded the in vitro ration, indicating extensive lipid peroxidation. Vitamin C treatment reduced the extent of lipid peroxidation in vivo as determined by the ratio of oxidized/reduced vitamin C. Title: Ascorbic acid, lipid peroxidation, and aging Author: Leibovitz, Brian Evan Year: 1979 The role of ascorbic acid with regard to lipid peroxidation and aging has been examined. A thorough literature analysis indicates that free radical-induced lipid peroxidation is a plausible biochemical explanation for aging. Lipid peroxidation causes cellular damage due to altered enzyme activities, error-prone nucleic acid metabolism, and membrane dysfunction, as well as the accumulation of aging pigments in the lysomes. Ascorbic acid, a water soluble free radical quencher, was examined with regard to carbon tetra-chloride-induced lipid peroxidation and in vivo aging. Carbon tetrachloride, a well-known free radical inducer, caused marked increases in the ration of oxidized/reduced vitamin C only in the organs which metabolize carbon tetrachloride to the free radical form. Vitamin C treatment, 250 mg% in the drinking water, reduced the extent of carbon tetrachloride=induced lipid peroxidation. Aging is associated with marked increases in the ration of oxidized/reduced vitamin C in all organs examined with the exception of thymus. In organs exposed to high oxygen tensions, or in those exposed to high levels of free radicals, the ration of oxidized/reduced vitamin C exceeded the in vitro ration, indicating extensive lipid peroxidation. Vitamin C treatment reduced the extent of lipid peroxidation in vivo as determined by the ratio of oxidized/reduced vitamin C. Close

• 43. [Article] Associations Between Prenatal Exposure to Air Pollution, Small for Gestational Age, and Term Low Birthweight in a State-Wide Birth Cohort

  A range of health effects, including adverse pregnancy outcomes, have been associated with exposure to ambient concentrations of particulate matter (PM) and ozone (O3). The objective of this study was ...

  Citation × Citation Citation Abstract Copy Title: Associations Between Prenatal Exposure to Air Pollution, Small for Gestational Age, and Term Low Birthweight in a State-Wide Birth Cohort Author: Vinikoor-Imler, Lisa C., Davis, J. Allen, Meyer, Robert E., Messer, Lynne C., Luben, Thomas J. Year: 2014 A range of health effects, including adverse pregnancy outcomes, have been associated with exposure to ambient concentrations of particulate matter (PM) and ozone (O3). The objective of this study was to determine whether maternal exposure to fine particulate matter (PM2.5) and O3 during pregnancy is associated with the risk of term low birthweight and small for gestational age infants in both single and co-pollutant models. Term low birthweight and small for gestational age were determined using all birth certificates from North Carolina from 2003 to 2005. Ambient air concentrations of PM2.5 and O3 were predicted using a hierarchical Bayesian model of air pollution that combined modeled air pollution estimates from the EPA׳s Community Multi-Scale Air Quality (CMAQ) model with air monitor data measured by the EPA׳s Air Quality System. Binomial regression, adjusted for multiple potential confounders, was performed. In adjusted single-pollutant models for the third trimester, O3 concentration was positively associated with small for gestational age and term low birthweight births [risk ratios for an interquartile range increase in O3: 1.16 (95% CI 1.11, 1.22) for small for gestational age and 2.03 (95% CI 1.80, 2.30) for term low birthweight]; however, inverse or null associations were observed for PM2.5 [risk ratios for an interquartile range increase in PM2.5: 0.97 (95% CI 0.95, 0.99) for small for gestational age and 1.01 (95% CI 0.97, 1.06) for term low birthweight]. Findings were similar in co-pollutant models and linear models of birthweight. These results suggest that O3 concentrations in both urban and rural areas may be associated with an increased risk of term low birthweight and small for gestational age births. Title: Associations Between Prenatal Exposure to Air Pollution, Small for Gestational Age, and Term Low Birthweight in a State-Wide Birth Cohort Author: Vinikoor-Imler, Lisa C., Davis, J. Allen, Meyer, Robert E., Messer, Lynne C., Luben, Thomas J. Year: 2014 A range of health effects, including adverse pregnancy outcomes, have been associated with exposure to ambient concentrations of particulate matter (PM) and ozone (O3). The objective of this study was to determine whether maternal exposure to fine particulate matter (PM2.5) and O3 during pregnancy is associated with the risk of term low birthweight and small for gestational age infants in both single and co-pollutant models. Term low birthweight and small for gestational age were determined using all birth certificates from North Carolina from 2003 to 2005. Ambient air concentrations of PM2.5 and O3 were predicted using a hierarchical Bayesian model of air pollution that combined modeled air pollution estimates from the EPA׳s Community Multi-Scale Air Quality (CMAQ) model with air monitor data measured by the EPA׳s Air Quality System. Binomial regression, adjusted for multiple potential confounders, was performed. In adjusted single-pollutant models for the third trimester, O3 concentration was positively associated with small for gestational age and term low birthweight births [risk ratios for an interquartile range increase in O3: 1.16 (95% CI 1.11, 1.22) for small for gestational age and 2.03 (95% CI 1.80, 2.30) for term low birthweight]; however, inverse or null associations were observed for PM2.5 [risk ratios for an interquartile range increase in PM2.5: 0.97 (95% CI 0.95, 0.99) for small for gestational age and 1.01 (95% CI 0.97, 1.06) for term low birthweight]. Findings were similar in co-pollutant models and linear models of birthweight. These results suggest that O3 concentrations in both urban and rural areas may be associated with an increased risk of term low birthweight and small for gestational age births. Close

• 44. [Article] Growing old and going straight: examining the role of age in criminal career termination

  This study was designed to investigate mid-life desistance from crime as a function of general mid-life change. Adult developmental theory postulates that major occupational or lifestyle changes occur ...

  Citation × Citation Citation Abstract Copy Title: Growing old and going straight: examining the role of age in criminal career termination Author: Jolin, Annette I. Year: 1985 This study was designed to investigate mid-life desistance from crime as a function of general mid-life change. Adult developmental theory postulates that major occupational or lifestyle changes occur during mid-life, more so than during other developmental periods in adulthood. Such changes are said to occur in conjunction with specific transitional processes experienced by the middle-aged male. The abandonment of a criminal career at mid-life is viewed as a significant occupational and lifestyle change. It is examined in relation to the postulated transitional processes affecting aspects of the life areas of work and social relationships, as well as health and psychological well-being. Structured interviews were conducted with a small group of former career criminals and a small group of currently imprisoned middle-aged career offenders. Career offenders were compared with middle-age general population men, and former career offenders were compared with imprisoned career offenders. Limitations of the research design and the sampling methods are also discussed. The findings suggest that middle-aged career offenders, regardless of whether they have terminated their criminal careers or are still imprisoned, in large part resemble general population men in terms of mid-life concerns. A comparative analysis of ex-offender and inmate responses suggests that while the men resemble each other closely in the area of mid-life concerns, successful change away from a criminal career at mid-life means that mid-life developmental tasks must be accompanied by relatively well-developed social relationships and the ability to gain control of drug and alcohol problems. Title: Growing old and going straight: examining the role of age in criminal career termination Author: Jolin, Annette I. Year: 1985 This study was designed to investigate mid-life desistance from crime as a function of general mid-life change. Adult developmental theory postulates that major occupational or lifestyle changes occur during mid-life, more so than during other developmental periods in adulthood. Such changes are said to occur in conjunction with specific transitional processes experienced by the middle-aged male. The abandonment of a criminal career at mid-life is viewed as a significant occupational and lifestyle change. It is examined in relation to the postulated transitional processes affecting aspects of the life areas of work and social relationships, as well as health and psychological well-being. Structured interviews were conducted with a small group of former career criminals and a small group of currently imprisoned middle-aged career offenders. Career offenders were compared with middle-age general population men, and former career offenders were compared with imprisoned career offenders. Limitations of the research design and the sampling methods are also discussed. The findings suggest that middle-aged career offenders, regardless of whether they have terminated their criminal careers or are still imprisoned, in large part resemble general population men in terms of mid-life concerns. A comparative analysis of ex-offender and inmate responses suggests that while the men resemble each other closely in the area of mid-life concerns, successful change away from a criminal career at mid-life means that mid-life developmental tasks must be accompanied by relatively well-developed social relationships and the ability to gain control of drug and alcohol problems. Close

• 45. [Article] A study of Leslie model under stochastic environments

  The prediction and analysis of changes in the numbers of biological populations rest on mathematical formulations of demographic events (births and deaths) classified by the age of individuals. The development ...

  Citation × Citation Citation Abstract Copy Title: A study of Leslie model under stochastic environments Author: Shaukat, Kamran Year: 1981 The prediction and analysis of changes in the numbers of biological populations rest on mathematical formulations of demographic events (births and deaths) classified by the age of individuals. The development of demographic theory when birth and death rates vary statistically over time is the central theme of this work. A study of the standard Leslie model for the demographic dynamics of populations in variable environments is made. At each time interval a Leslie matrix of survival rates and fertilities of a population is chosen according to a Markov process and the population numbers in different age classes are computed. Analytical bounds are developed for the logarithmic growth rate and the age-structure of a population after long times. For a two dimensional case, it is shown analytically that a uniform distribution results for the age-structure if the survival rate from the first to the second age-class is a uniformly distributed random quantity with no serial auto correlation. Numerical studies are made which lead to similar conclusions when the survival rate obeys other distributions. It is found that the variance in the survival parameter is linearly related to the variance in the age structure. An efficient algorithm is developed for numerical simulations on a computer by considering a time sequence of births rather than whole populations. The algorithm is then applied to an example in three dimensions to calculate a sequence of births when the survival rate from the first to the second age-class is a random parameter. Numerical values for the logarithmic growth rate and the logarithmic variance for a population and the probability of extinction are obtained and then compared to the analytical results reported here and elsewhere. Title: A study of Leslie model under stochastic environments Author: Shaukat, Kamran Year: 1981 The prediction and analysis of changes in the numbers of biological populations rest on mathematical formulations of demographic events (births and deaths) classified by the age of individuals. The development of demographic theory when birth and death rates vary statistically over time is the central theme of this work. A study of the standard Leslie model for the demographic dynamics of populations in variable environments is made. At each time interval a Leslie matrix of survival rates and fertilities of a population is chosen according to a Markov process and the population numbers in different age classes are computed. Analytical bounds are developed for the logarithmic growth rate and the age-structure of a population after long times. For a two dimensional case, it is shown analytically that a uniform distribution results for the age-structure if the survival rate from the first to the second age-class is a uniformly distributed random quantity with no serial auto correlation. Numerical studies are made which lead to similar conclusions when the survival rate obeys other distributions. It is found that the variance in the survival parameter is linearly related to the variance in the age structure. An efficient algorithm is developed for numerical simulations on a computer by considering a time sequence of births rather than whole populations. The algorithm is then applied to an example in three dimensions to calculate a sequence of births when the survival rate from the first to the second age-class is a random parameter. Numerical values for the logarithmic growth rate and the logarithmic variance for a population and the probability of extinction are obtained and then compared to the analytical results reported here and elsewhere. Close

• 46. [Article] Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings

  Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and ...

  Citation × Citation Citation Abstract Copy Title: Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings Author: Peterson, Kate, Calabria, Lalita M., Miller, Jesse E.D., Brown-Clay, Jesse Year: 2017 Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and forest health. Stand age has been implicated as a key factor in driving epiphytic species diversity and community composition. However, understanding the influence of substrate age, independent of the many confounding variables that affect live and dead wood substrates in a forest habitat, can be difficult. To test the hypothesis that substrate age has distinct effects on lichen community assembly independent of surface area, we sampled communities of calicioid lichens and fungi growing on wooden buildings that ranged from 2 to 82 years old. We found a total of 17 species, with a strong positive correlation between species richness and substrate age. We also tested the effects of surface area on species richness and found no relationship between the two variables. Our results indicate that substrate age influenced community composition; non-lichenized calicioid species acted as early colonizers and six calicioid species were recorded only on the oldest substrate. Old-growth associate species were found on substrates of varying ages, implying that additional variables may also be responsible for the colonization of old-growth associate species. Copyright © 2017 by The American Bryological and Lichenological Society, Inc. Title: Substrate Age Influences Species Richness and Community Composition of Calicioid Lichens and Fungi on Wooden Buildings Author: Peterson, Kate, Calabria, Lalita M., Miller, Jesse E.D., Brown-Clay, Jesse Year: 2017 Identifying processes that drive epiphytic lichen diversity and succession is important for directing conservation efforts and developing forest management plans for the maintenance of biodiversity and forest health. Stand age has been implicated as a key factor in driving epiphytic species diversity and community composition. However, understanding the influence of substrate age, independent of the many confounding variables that affect live and dead wood substrates in a forest habitat, can be difficult. To test the hypothesis that substrate age has distinct effects on lichen community assembly independent of surface area, we sampled communities of calicioid lichens and fungi growing on wooden buildings that ranged from 2 to 82 years old. We found a total of 17 species, with a strong positive correlation between species richness and substrate age. We also tested the effects of surface area on species richness and found no relationship between the two variables. Our results indicate that substrate age influenced community composition; non-lichenized calicioid species acted as early colonizers and six calicioid species were recorded only on the oldest substrate. Old-growth associate species were found on substrates of varying ages, implying that additional variables may also be responsible for the colonization of old-growth associate species. Copyright © 2017 by The American Bryological and Lichenological Society, Inc. Close

• 47. [Article] An examination of disengagement among elderly people in a low income public housing facility

  Six general hypotheses guided the development of the study: The older person experiences progressive disengagement from society resulting in feelings of isolation, depression, frustration, and despair; ...

  Citation × Citation Citation Abstract Copy Title: An examination of disengagement among elderly people in a low income public housing facility Author: Bennion, Linda, Paradis, Marion, Petrie, Sheila Year: 1969 Six general hypotheses guided the development of the study: The older person experiences progressive disengagement from society resulting in feelings of isolation, depression, frustration, and despair; the aging person is dissatisfied with the degree of this process of social disengagement; the aging person gains satisfaction by participating in activities which lead to individual growth and/or benefit to others; the aging person lacks capacity and/or desire to participate in many activities or to continue the full-time roles of parent, job holder, and citizen; the aging person would like to choose his activities according to his desires and needs; and the aging person will more likely participate in activities if he is able to obtain adequate health care and has financial security. Descriptive and statistical inferential tests were used to analyze the data. A relatively small percentage of possible disengagement in the recreational, occupational, and family life areas occurred during the individual's life span from age 40 to age 70. The percentage of possible disengagement in these areas increased dramatically in the life span from age 70. Most of the respondents rejected loneliness and depression and felt in good spirits most of the time. A tendency toward less and less contact with others was seen. Statistically significant differences were found between activities which were presently enjoyed which were basically individual and passive in nature; and activities respondents would plan for themselves, which were of a significantly more social nature involving them in rewarding activity with others. Statistically significant differences were found between interest in the activity program available at Northwest Tower, basically recreation and entertainment; and the activities respondents would include in their program, mainly designed for self-enhancement or benefit to others. Statistically significant differences were also found between the number of activities available and the smaller number desired. The findings suggested that the preponderance of the respondents desired to withdraw from major responsibilities outside their household. Of those who desired responsibilities such as occupation, family or civic, they were prevented from assuming them most of the time because of their increasing age, deteriorating health, and lack of money. These were also the main factors operant in restricting their activity and preventing them from enjoying satisfactory ways of living. The majority of opinions as to society's responsibility to the aging suggested that intervention was necessary to provide financial security, health care, and better and cheaper methods of transportation. The findings of the study suggested the importance of more intensive research in planning programs directly related to meeting the individual needs of elderly people. Title: An examination of disengagement among elderly people in a low income public housing facility Author: Bennion, Linda, Paradis, Marion, Petrie, Sheila Year: 1969 Six general hypotheses guided the development of the study: The older person experiences progressive disengagement from society resulting in feelings of isolation, depression, frustration, and despair; the aging person is dissatisfied with the degree of this process of social disengagement; the aging person gains satisfaction by participating in activities which lead to individual growth and/or benefit to others; the aging person lacks capacity and/or desire to participate in many activities or to continue the full-time roles of parent, job holder, and citizen; the aging person would like to choose his activities according to his desires and needs; and the aging person will more likely participate in activities if he is able to obtain adequate health care and has financial security. Descriptive and statistical inferential tests were used to analyze the data. A relatively small percentage of possible disengagement in the recreational, occupational, and family life areas occurred during the individual's life span from age 40 to age 70. The percentage of possible disengagement in these areas increased dramatically in the life span from age 70. Most of the respondents rejected loneliness and depression and felt in good spirits most of the time. A tendency toward less and less contact with others was seen. Statistically significant differences were found between activities which were presently enjoyed which were basically individual and passive in nature; and activities respondents would plan for themselves, which were of a significantly more social nature involving them in rewarding activity with others. Statistically significant differences were found between interest in the activity program available at Northwest Tower, basically recreation and entertainment; and the activities respondents would include in their program, mainly designed for self-enhancement or benefit to others. Statistically significant differences were also found between the number of activities available and the smaller number desired. The findings suggested that the preponderance of the respondents desired to withdraw from major responsibilities outside their household. Of those who desired responsibilities such as occupation, family or civic, they were prevented from assuming them most of the time because of their increasing age, deteriorating health, and lack of money. These were also the main factors operant in restricting their activity and preventing them from enjoying satisfactory ways of living. The majority of opinions as to society's responsibility to the aging suggested that intervention was necessary to provide financial security, health care, and better and cheaper methods of transportation. The findings of the study suggested the importance of more intensive research in planning programs directly related to meeting the individual needs of elderly people. Close

• 48. [Article] Bus Replacement Modeling and the Impacts of Budget Constraints, Fleet Cost Variability, and Market Changes on Fleet Costs and Optimal Bus Replacement Age, A Case Study

  Overwhelming evidence throughout the literature has shown that bus overhead and maintenance (O&M) costs increase as buses age. This has implications toward a fleet manager's decision of when one should ...

  Citation × Citation Citation Abstract Copy Title: Bus Replacement Modeling and the Impacts of Budget Constraints, Fleet Cost Variability, and Market Changes on Fleet Costs and Optimal Bus Replacement Age, A Case Study Author: Boudart, Jesse Alexander Year: 2011 Overwhelming evidence throughout the literature has shown that bus overhead and maintenance (O&M) costs increase as buses age. This has implications toward a fleet manager's decision of when one should buy, use, or sell buses to minimize total fleet costs. Unfortunately, there are uncertain market conditions associated with bus fleets that cloud the manager's ability to make appropriate decisions. Using integer programming (IP), O&M trends and changing market conditions are integrated into a model to better analyze bus fleets. Due to recent budget constraints of transit agencies, needs for a bus fleet replacement model have arisen. King County in Washington State has supplied cost aggregated data of their New Flyer (NF) and NF hybrid buses. These data have been analyzed to create statistical relationships based on rising O&M costs per mile with age, which are then integrated with the IP model to determine the impact of changing diesel prices, potential carbon dioxide (CO2) emissions costs, uncertain maintenance costs, and bus purchase cost subsidies. The goal is to aid fleet managers to determine the costs of early or delayed suboptimal bus replacement timing and the impacts of market variability on fleet costs and optimal replacement timing. The optimal replacement age for NF and NF hybrid buses based on King County data and current fuel prices of $3.99/gal are 16.7 and 18.3 years, respectively. It has been consistently observed that greater expense is incurred when buses are replaced earlier rather than later from optimal. To minimize total CO2 emissions (including operation and construction emissions), buses should be replaced slightly before the optimal replacement time without considering CO2 emissions. High diesel prices and CO2 emissions had little or no effect, on when buses should be replaced. However, higher maintenance costs reduced the optimal replacement time by almost two years. Although NF hybrid buses have been found to have no economic advantage over conventional buses, this finding may be a consequence of the different costs associated to the different routes operated by hybrid and conventional buses. Due to the lack of detailed King County's route level historical data, a study of the economic competitiveness of NF hybrids against conventional buses is outside the scope of this thesis. If buses are used less with age, the optimal replacement age is reduced. The optimal replacement age also dropped significantly when the Federal Transit Agency's procurement assistance is applied into the model. The procurement assistance can be up to 80% of the capital costs and can be considered a purchase subsidy from the transit agency viewpoint. If purchase subsidies decrease bus purchase prices by 1%, the optimal replacement age drops approximately 1.5%. When the bus purchase price is reduced by 80%, the optimal bus replacement age is less than 12 years, the FTA's minimum replacement age. Title: Bus Replacement Modeling and the Impacts of Budget Constraints, Fleet Cost Variability, and Market Changes on Fleet Costs and Optimal Bus Replacement Age, A Case Study Author: Boudart, Jesse Alexander Year: 2011 Overwhelming evidence throughout the literature has shown that bus overhead and maintenance (O&M) costs increase as buses age. This has implications toward a fleet manager's decision of when one should buy, use, or sell buses to minimize total fleet costs. Unfortunately, there are uncertain market conditions associated with bus fleets that cloud the manager's ability to make appropriate decisions. Using integer programming (IP), O&M trends and changing market conditions are integrated into a model to better analyze bus fleets. Due to recent budget constraints of transit agencies, needs for a bus fleet replacement model have arisen. King County in Washington State has supplied cost aggregated data of their New Flyer (NF) and NF hybrid buses. These data have been analyzed to create statistical relationships based on rising O&M costs per mile with age, which are then integrated with the IP model to determine the impact of changing diesel prices, potential carbon dioxide (CO2) emissions costs, uncertain maintenance costs, and bus purchase cost subsidies. The goal is to aid fleet managers to determine the costs of early or delayed suboptimal bus replacement timing and the impacts of market variability on fleet costs and optimal replacement timing. The optimal replacement age for NF and NF hybrid buses based on King County data and current fuel prices of $3.99/gal are 16.7 and 18.3 years, respectively. It has been consistently observed that greater expense is incurred when buses are replaced earlier rather than later from optimal. To minimize total CO2 emissions (including operation and construction emissions), buses should be replaced slightly before the optimal replacement time without considering CO2 emissions. High diesel prices and CO2 emissions had little or no effect, on when buses should be replaced. However, higher maintenance costs reduced the optimal replacement time by almost two years. Although NF hybrid buses have been found to have no economic advantage over conventional buses, this finding may be a consequence of the different costs associated to the different routes operated by hybrid and conventional buses. Due to the lack of detailed King County's route level historical data, a study of the economic competitiveness of NF hybrids against conventional buses is outside the scope of this thesis. If buses are used less with age, the optimal replacement age is reduced. The optimal replacement age also dropped significantly when the Federal Transit Agency's procurement assistance is applied into the model. The procurement assistance can be up to 80% of the capital costs and can be considered a purchase subsidy from the transit agency viewpoint. If purchase subsidies decrease bus purchase prices by 1%, the optimal replacement age drops approximately 1.5%. When the bus purchase price is reduced by 80%, the optimal bus replacement age is less than 12 years, the FTA's minimum replacement age. Close

• 49. [Article] Age, emotional maturity and the decision to marry

  The decision to marry and choice of mate are two issues contemplated by most individuals during their lifetime. It is our belief that the manner in which an individual makes these decisions is a reflection ...

  Citation × Citation Citation Abstract Copy Title: Age, emotional maturity and the decision to marry Author: Duclos, Patricia Ann, Thomas, David F., Zusman, Joanne Year: 1971 The decision to marry and choice of mate are two issues contemplated by most individuals during their lifetime. It is our belief that the manner in which an individual makes these decisions is a reflection of that individual’s level of emotional maturity. In our society, the right to enter into a marriage agreement is largely determined by chronological age. Our research problem began with the hypothesis that there is no direct relationship between chronological age and emotional maturity at the time of marriage. For our study, marriages were divided into two general categories: 1) teenage marriages in which at least one partner was 20 years of age or younger, and 2) adult marriages in which one partner was Z1 years of age or older. The three independent variables studied were: age, sex of respondent, and sex of spouse. The dependent variable was emotional maturity. Emotional maturity was operationally defined by a questionnaire consisting of 67 statements about why people decide to marry, and why they chose their particular spouse. A panel of 12 experts in the field of marriage counseling were asked to rate each statement on a seven point scale of maturity-immaturity. The range and mode for each statement was computed and used to construct a new questionnaire consisting of 30 statements. Emotional maturity was defined by the absolute difference between the individual respondent’s rating and the expert’s modal response. A sample population was selected using recently married individuals who had applied for marriage licenses in Multnomah County, Oregon. The second questionnaire was mailed to the respondents. A 2 x 2 x 2 factorial design was used to identify which variable or combination of variables accounted for any discrepancy. A multiple regression analysis and a F test were run to test the hypothesis of the study. The data received supported the null hypothesis. However, there were several conceptual and methodological limitations to the study which raise questions as to the reliability of the measuring instrument and use of the concept of emotional maturity. Title: Age, emotional maturity and the decision to marry Author: Duclos, Patricia Ann, Thomas, David F., Zusman, Joanne Year: 1971 The decision to marry and choice of mate are two issues contemplated by most individuals during their lifetime. It is our belief that the manner in which an individual makes these decisions is a reflection of that individual’s level of emotional maturity. In our society, the right to enter into a marriage agreement is largely determined by chronological age. Our research problem began with the hypothesis that there is no direct relationship between chronological age and emotional maturity at the time of marriage. For our study, marriages were divided into two general categories: 1) teenage marriages in which at least one partner was 20 years of age or younger, and 2) adult marriages in which one partner was Z1 years of age or older. The three independent variables studied were: age, sex of respondent, and sex of spouse. The dependent variable was emotional maturity. Emotional maturity was operationally defined by a questionnaire consisting of 67 statements about why people decide to marry, and why they chose their particular spouse. A panel of 12 experts in the field of marriage counseling were asked to rate each statement on a seven point scale of maturity-immaturity. The range and mode for each statement was computed and used to construct a new questionnaire consisting of 30 statements. Emotional maturity was defined by the absolute difference between the individual respondent’s rating and the expert’s modal response. A sample population was selected using recently married individuals who had applied for marriage licenses in Multnomah County, Oregon. The second questionnaire was mailed to the respondents. A 2 x 2 x 2 factorial design was used to identify which variable or combination of variables accounted for any discrepancy. A multiple regression analysis and a F test were run to test the hypothesis of the study. The data received supported the null hypothesis. However, there were several conceptual and methodological limitations to the study which raise questions as to the reliability of the measuring instrument and use of the concept of emotional maturity. Close

• 50. [Article] Comparison of scores obtained on the PPVT and the PPVT-R

  The Peabody Picture Vocabulary Test (PPVT) is a widely used receptive vocabulary screening tool, but it is not without its limitations, such as inadvisable I.Q. usage and a standardization procedure that ...

  Citation × Citation Citation Abstract Copy Title: Comparison of scores obtained on the PPVT and the PPVT-R Author: Choong, Jennie L.M. Year: 1981 The Peabody Picture Vocabulary Test (PPVT) is a widely used receptive vocabulary screening tool, but it is not without its limitations, such as inadvisable I.Q. usage and a standardization procedure that lacks scope. A revision of the PPVT, known as the Peabody Picture Vocabulary Test-Revised (PPVT-R) was published in 1981, and contains a more complete standardization procedure as well as some structural changes of the test itself (Dunn, 1981). Speech/language pathology, whose diagnosticians most commonly use the age equivalent value, is a profession that would gain from information which deals with the equivalency of the PPVT-R to the original PPVT. The purpose of the study was to compare age equivalent values obtained from the PPVT and the PPVT-R for a preschool aged population. Specifically, this study sought to discover whether or not significant differences existed between the age equivalent values derived from the PPVT and the PPVT-R. Eighty children, age three years, six months to four years, six months participated as subjects in the study, selected on the basis of their chronological age and enrollment in one of ten selected preschools. The subjects were divided into four groups (N=20), and each group was administered one form of the PPVT (A or B) and one form of the PPVT-R ( L or M). The resultant groupings were: I (A and L); II (A and M); III ( B and L); and IV ( B and M). Title: Comparison of scores obtained on the PPVT and the PPVT-R Author: Choong, Jennie L.M. Year: 1981 The Peabody Picture Vocabulary Test (PPVT) is a widely used receptive vocabulary screening tool, but it is not without its limitations, such as inadvisable I.Q. usage and a standardization procedure that lacks scope. A revision of the PPVT, known as the Peabody Picture Vocabulary Test-Revised (PPVT-R) was published in 1981, and contains a more complete standardization procedure as well as some structural changes of the test itself (Dunn, 1981). Speech/language pathology, whose diagnosticians most commonly use the age equivalent value, is a profession that would gain from information which deals with the equivalency of the PPVT-R to the original PPVT. The purpose of the study was to compare age equivalent values obtained from the PPVT and the PPVT-R for a preschool aged population. Specifically, this study sought to discover whether or not significant differences existed between the age equivalent values derived from the PPVT and the PPVT-R. Eighty children, age three years, six months to four years, six months participated as subjects in the study, selected on the basis of their chronological age and enrollment in one of ten selected preschools. The subjects were divided into four groups (N=20), and each group was administered one form of the PPVT (A or B) and one form of the PPVT-R ( L or M). The resultant groupings were: I (A and L); II (A and M); III ( B and L); and IV ( B and M). Close