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Demography of Australian fur seals (Arctocephalus pusillus doriferus)Gibbens, John Robert January 2009 (has links)
The Australian fur seal (Arctocephalus pusillus doriferus) population has displayed a relatively slow rate of recovery since being hunted by commercial sealers during the early 19th century. Despite this, population abundance doubled in the past 2 – 3 decades, indicating that the population growth rate has recently increased. Yet, the factors influencing the population’s dynamics are poorly understood, primarily because basic demographic rates are unknown. / Female age, survival, fecundity, breeding and physiology were studied at Kanowna Island, Bass Strait, Australia, between 2003 – 2006 by conducting censuses and captures (n = 294). Mark-recapture estimates of pup production were used to validate direct pup counts, allowing a 9-year dataset to be used for calculation of the population growth rate (2.2% p.a.) and investigation of environmental influences on reproductive success. Annual pup production (x = 3108) was synchronous, with 90% of births occurring within 28 days of the median birth date of 23 November. Births occurred earlier in years when pup production and female body condition were high and these factors were correlated with local oceanographic indicators, suggesting that reproductive success is constrained by environmentally-mediated nutritional stress. / Pregnancy was assessed by blood plasma progesterone radioimmunoassay and the pupping status of the same females was observed during breeding season. Despite high mid-gestation pregnancy rates (x = 84%), the birth rate was lower than in other fur seals (x = 53%), suggesting that late-term abortion is common. Lactating females were less likely to pup, indicating that nutrition may be insufficient to support concurrent lactation and gestation. / Age and morphometric data were used to construct body growth, age structure and survivorship models. Adult female survival rates were similar to those of other fur seals (x = 88.5%). A life table was constructed and its age-specific survival and fecundity rates used in a Leslie-matrix model to project the population growth rate (2.2% p.a.) and determine the relative influence of each parameter. The abundance of female non-pups was 6 times greater than that of female pups, which is approximately 50% higher than previous conversion factors used to extrapolate population abundance from pup censuses in Australian fur seals. However, if the non-pup sex ratios of other otariids are considered, the pup:population conversion factor is 4.5. / Compared to a study performed before the recent population increase, the modern population displays similar body growth and fecundity rates but higher survival rates. This suggests that recent population growth resulted from a relaxation of hunting and/or predation mortality rather than from increased food availability. The low population growth rate is attributed to a low birth rate associated with nutritional stress, yet despite this, body growth occurs rapidly. Such characteristics are typical of sea lions rather than fur seals, perhaps because Australian fur seals employ the typical sea lion strategy of using benthic foraging to exploit a continental shelf habitat. The effect of ecological niche on population dynamics in the Otariidae is discussed.
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Essays on financial and international economicsSu, Xiaojing 15 May 2009 (has links)
No description available.
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Essays on financial and international economicsSu, Xiaojing 15 May 2009 (has links)
No description available.
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Research on job stress, social support and job performance. The study here is of Kaohsiung City overnment employees.Shih, Hui-wen 02 September 2005 (has links)
This research is aimed to look into the relevance between job stress and job performance
of Kaohsiung City Government employees, and to observe whether social support will have
an effect on this. This research will serve as a reference for people in charge of making
policies.
Documents will serve as the basis for research, as well as some statistical methods
such as conducting the poll through questionnaires, factor analysis, descriptive statistic, T test,
ANOVA, correlation analysis, regression analysis and other relevant analyses. There are
several discoveries based on these analyses and studies:
1. The job stress of the employees of Kaohsiung City Government comes from the nature of
work and structural specialty.
2. The highest level within the various levels of the job performance of Kaohsiung City
Government employees is the mission efficiency, which shows the same result as the
opinion poll does.
3. Gender serves as an obvious difference when it comes to job stress, which shows that
female feels more about that than male.
4. Schooling record also serves as an obvious difference when it comes to job stress. In the
part of structural specialty, employees owning master or higher degree usually have a
bigger job stress than those owning senior or vocational high school diploma or below.
5. Social support and job stress have statistically negative influence, which means that more
social support will reduce the causes of job stress. This view is also concurred by many
scholars.
6. Job stress and job performance have statistically negative influence. This is also
concurred by many scholars such as Schuler.
7. Social support does not have an influential effect between job stress and job performance,
which means that social support does not have the effect of stress buffer as some scholars
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such as Fenlason & Beehr claim.
8. The condition of marriage has an influential effect between job stress and job
performance. Those who are married tend to have the phenomenon that the more job
stress they have, the less job performance they achieve.
It is the first time that this report is aimed to study the job stress of Kaohsiung City
Government employees, and it affirms that social support, especially the support from the
senior officer, will have the effect of decreasing job stress. The result of this research may
serve as a policy reference for Kaohsiung City Government to raise the job performance of its
employees.
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Demographic characteristics of transit-oriented development areas in CaliforniaHuang, Chao-Hsing, active 2008 21 November 2013 (has links)
This study is to understand how Transit-Oriented Development influences
demographic characteristics within its boundary. Case studies from the California TOD
database was used. Through the changes of TOD during 1990 and 2000 and the
comparison of trends in TODs and located regions, many TODs are low-income areas and
such factors induces other demographic phenomenon. Meanwhile, the level of transit use
did not change much and the vehicle ownership did not decrease definitely. Though such
facts might imply the inefficiency of TOD, there are other factors such as economic and
transit environment that cause this fact. Thus, TOD is actually influenced heavily by
background policies, experience, and supportive transit circumstances. / text
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Health Expenditures, Time to Death, and Age: A Study of Individual-level, Longitudinal Data to Identify the Combined Role of Age and Mortality in Determining Health Utilization of the ElderlyPayne, Greg Jason 23 February 2011 (has links)
While there is great concern about the potential impact of aging populations on health care systems in the developed world, evidence from recent decades has shown at best a weak relationship between population aging and health expenditures at the aggregate level. This thesis explores the literature that frames the relationship between age and health care utilization in the context of reduced mortality and shorter periods of morbidity at the end of life. We add to this literature with an empirical study of individual health expenditures of the British Columbia senior population in the years 1991-2001 in the categories of hospital services, continuing care,
doctor billings, and pharmaceutical prescriptions. Expenditures for decedent and survivors of the same age are compared and are fitted to a model using age and time-to-death as explanatory factors. The partial derivative of the model with respect to age is analyzed for empirical
estimates of the effect of age after controlling for time-to-death. Results show that decedent costs rose over the study period while costs for survivors fell, particularly in continuing care, so
that the relative cost of dying increased. The effect of age, after controlling for time to death, was muted or negative for hospitals, doctors, and drugs, but strongly positive for continuing care and, as a result, for all services combined. Overall, these results suggest that age is not a ‘red
herring’, as some researchers have suggested, with respect to forecasting future demands on health systems. While future reductions in mortality and morbidity could mitigate pressures on hospitals, aging populations will put increased pressure on long-term residential care and other
forms of social care.
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Conch Population Demographics and Habitat Association Near Port Everglades Inlet, FloridaBerry, Charlotte A. 01 May 2014 (has links)
The queen conch (Strombus gigas) is a large marine gastropod found throughout the tropical western Atlantic including Florida. Overfishing and habitat loss have led to Caribbean-wide population declines requiring regional protections. On Florida’s east coast, aggregations of conch were previously reported just south of a major shipping port near Ft. Lauderdale, unusually high latitude for the species. This study was designed to investigate the spatial extent and population demographics of the Ft. Lauderdale conch. In summer 2012, broad-scale population surveys were conducted to document benthic cover and conch distribution and size data along 72 random transects stratified across four habitats within 2 km north and south of the inlet. Younger conchs were found throughout the study area, but mostly in the colonized pavement west (CPW) habitat while old conchs were found exclusively at one CPW site south of the inlet. Significantly more conch were found on the CPW south habitat than any other. Benthic cover data suggests that CPW south may have a unique community composition dominated by macroalgae and sand. In summer 2013, the CPW south habitat was surveyed using cross-shelf transects measuring aggregation extent and demographics. Five hundred and twenty five conch were found, at a density of 495 conch per hectare. Confirmed mating sightings, females with eggs, and solitary egg masses were found indicating mating in this nearshore habitat is successful. Future research should include expanded broad-scale surveys to determine if other aggregations exist and monitoring to examine the effects of environmental change on this vulnerable species.
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The location of hazardous waste facilitiesOakes, John Michael 01 January 1997 (has links)
This study evaluates "environmental equity" in the residential distribution of commercial hazardous waste treatment, storage and disposal facilities (TSDFs). Because of claims that TSDFs are disproportionately sited in poor and black neighborhoods, this area of research has become important to scholars, policymakers and community activists. Indeed, claims have generated significant changes in U.S. environmental policy, including the Environmental Protection Agency's (EPA's) establishment of the Office of Environmental Justice, several remedial Congressional bills and an Executive Order from President Clinton mandating Federal Agencies consider environmental justice issues. Yet empirical analyses are limited. Beyond a comprehensive literature review and a theoretical summary, this study contributes two broad analyses. First is a comprehensive cross-sectional analysis of the current distribution of TSDFs. Efforts are directed toward uncovering systematic differences between the demographic composition of neighborhoods with and without TSDFs. Importantly, proxy measures for zoning and market forces in addition to proxy measures of TSDF activity are employed. Second is a longitudinal analysis of TSDF siting focused on whether the composition of neighborhoods is systematically related to site selection decisions at the time of siting. Further analyses aim to find out if TSDFs significantly impact the demographic composition of host neighborhoods over time. Several data resources are employed. TSDF data were primarily compiled from the Environmental Services Directory, validated through the EPA's RCRIS data resource and a telephone survey. Neighborhood data come from the 1970, 1980 and 1990 tract-level Census files. Proxy measures of zoning and TSDF activity come from Dunn and Bradstreet industrial firm files and EPA's 1992 Toxic Release Inventory (TRI), respectively. Analyses reveal no stark evidence of environmental inequity in either the current distribution of TSDFs or longitudinally. Findings suggest TSDF neighborhoods are generally white, working-class, industrial neighborhoods--a finding consistent with some theories of urban structure and some previous research. More active TSDFs appear to be located in neighborhoods with smaller percentages of minority and poor persons. Simple conclusions are complicated by evidence suggesting TSDF neighborhoods are surrounded by poor and minority neighborhoods and other methodological obstacles, however. Implications for policy and research are discussed.
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Self-selection and migrants' destination choice: A study of Puerto Ricans in the United States and Puerto RicoKuenzi, Jeffrey John 01 January 1998 (has links)
The long-standing claim that migrating individuals are uniformly positively selected (i.e. possessing labor market skills of higher economic value than those who do not migrate) has been challenged in recent years. Research suggesting that some immigrants to the United States possess below average skills has generated debate over both the nature of migrant self-selection as well as the impact of immigration policy on the stock of immigrant flows. This debate has raised important theoretical questions about the relationship between the attributes of sending and receiving areas and the characteristics of migrants. This dissertation addresses the selectivity debate using a conditional logistic regression model of migrants' location choice. The model identifies the individual characteristics and location attributes that determine location choice and provides a unique approach to the issue of selectivity. The analysis tests two theoretical perspectives that have figured prominently in the economic and sociological literature on migration. The data are taken from the 1980 and 1990 U.S. Census Public Use Microdata Samples on Puerto Ricans living in the United States and Puerto Rico. A review of the growth and geographic dispersal of migration originating from Puerto Rico suggest a notable amount of human capital selectivity across migrant destinations. Recent data on metropolitan populations of Puerto Ricans in the United States and Puerto Rico reveal that the migratory process has lead to wide variation in the characteristics of individuals at different locations. The location choice analysis finds support for both theories of migrant self-selection. The results indicate that more competitive labor markets encourage positive selection and that larger migratory social networks encourage negative selection. This research makes important methodological and theoretical contributions to the literature. The analytical strategy taken in this study represents an original approach to the question of migrant self-selection. The location choice model provides the first simultaneous assessment of multiple causes of selectivity. The conceptualization of self-selection as the interaction between individual characteristics and location attributes is also innovative. The policy implications of this research are far-reaching. The results suggest that immigration criteria based on family reunification have a negative impact on immigrant selectivity by reinforcing the operation of migratory social networks. Further, the migration process examined in this analysis suggests that selectivity contributes to socio-economic segregation across geographic space.
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Demography and death in emergent industrial cities of New EnglandHautaniemi, Susan Irene 01 January 2002 (has links)
This dissertation examines the mortality experiences of two emerging industrial cities, Northampton and Holyoke, in the Connecticut River Valley of western Massachusetts, during the period from 1850 through 1910, and the processes that delayed the transition to lower mortality levels in New England. This was a period in which these two towns, and many others in New England, grew rapidly due to early industrialization and urbanization. Death rates rose after the middle of the nineteenth century and stabilized at high levels, only falling again after the turn of the twentieth century. This work is an anthropological enquiry into why life seems to have been more precarious in the emergent cities of New England as mortality was declining throughout western Europe. Some characteristics of these towns, for example, changing occupational, ethnic and age composition, can be ascertained from decennial census data. However, in order to analyze the relationship of mortality to changing population characteristics I use linked individual-level census and death records from 1850 to 1912 to analyze mortality across panels defined by the timing of decennial censuses. I also look at how individuals might have attempted to mitigate the risks of mortality through strategies of household formation and household economies. The use of individual-level linked census-death data in these communities supports detailed analyses of the changing risks of mortality over the emergence and eventual maturation of these industrializing urban centers. I find that the mortality experiences of Holyoke and Northampton were shaped by the processes that formed these unique communities: a large population of young adults, influxes of poorly-paid immigrant labor, densely crowded living and working conditions, and delays in adequate infrastructure, particularly clean water and sanitary sewerage. During the period mortality rose and the most vulnerable groups experienced the worst life chances. Over time, the communities matured. The population aged, growth slowed, outlying areas became accessible to industrial workers through a regional trolley system, and public works were better able to keep pace with population. Death from infectious and parasitic disease became less frequent, and death from chronic or degenerative disease more prevalent.
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