Rozprawy doktorskie: „Population decline”

1

Williams, Mari. "Japanese population decline". Connect to resource, 2006. http://hdl.handle.net/1811/6454.

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Thesis (Honors)--Ohio State University, 2006.
Title from first page of PDF file. Document formatted into pages: contains 13 p.; also includes graphics. Includes bibliographical references (p. 13). Available online via Ohio State University's Knowledge Bank.

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2

Uemura, Tetsuji. "Population decline, infrastructure and sustainability". Thesis, London School of Economics and Political Science (University of London), 2014. http://etheses.lse.ac.uk/1038/.

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Japan has experienced population decline since 2010 and the situation is expected to become more severe after 2030 with forecasts indicating an expected 30% decline from 2005 to 2055. Many other developed countries such as Germany and Korea are also experiencing depopulation. These demographic changes are expected to affect society at many levels such as labour markets decline, increased tax burden to sustain pension systems, and economic stagnation. Little is known however about the impacts of population decline on man-made physical infrastructure, such as possible deterioration of current infrastructure or increased financial burden of sustaining it. Infrastructure can be classified into 3 categories: point-type (e.g. buildings), point-network type (e.g. water supply) and network type (e.g. road). The impact of depopulation may vary according to the type of infrastructure. Previous research in this area has been limited in scope (e.g. case studies conducted in a single city focusing on a single type of infrastructure) and method (e.g. most research in the topic has been qualitative). This thesis presents a new comprehensive study on the impacts of population decline on infrastructure in Japan, taking into account all types of infrastructure and using a quantitative approach. Data collection methods include interviews and two large scale questionnaire surveys, the first conducted with municipalities and the second, a stated preference survey, conducted with members of the public. The goal of sustainable development is relevant even in a depopulated society, and hence a sustainable development framework is applied to the analysis where social, economic, environmental and engineering impacts are investigated. The main findings indicate that some infrastructure impacts observed and reported in depopulated areas do not seem to be related to any population decline; moreover, the preferences of citizens for infrastructure development is very similar between depopulated areas and non-depopulated areas. The results also suggest that the premises of Barro’s overlapping generations model, very relevant to a discussion of intergenerational decision making and related sustainability, appear to be rejected in this context.

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3

Gray, Richard. "A Design for Decline". Thesis, KTH, Arkitektur, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277845.

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Both in practice and theory, the focus in architecture is often largely about growth. Architecture is, therefore, a tool that we largely use to accommodate growth. However, whilst many cities are experiencing growth, many are facing population decline. Latvia’s capital Riga is one example of this. So while architecture often fixates on growth, the discourse on decline does not normally involve architecture. With this project, I sought to investigate the question: ‘How can we use architecture as a tool to accommodate decline?’ Through the study of an empty site in Riga, in an area which has lost 60% of its resident population since 2000, the project envisages a building designed to slowly consolidate the functions of a shrinking city over an extended time span. The proposal, a ‘House of Everything’ (Latvian: Viskautkā Māja) is developed in two main ways. First, through a strategy for the site, delineating the rules and parameters for the anticipated building and its functions. Second, with a detailed test, using the strategy to develop a completed building.

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4

Mooney, Graham. "The geography of mortality decline in Victorian London". Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359013.

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5

Tumenta, PN, JS Kok, Rijssel JC van, R. Buij, BM Croes, PJ Funston, Longh HH de i de Haes HA Udo. "Threat of rapid extermination of the lion (Panthera leo leo) in Waza National Park, Northern Cameroon". Blackwell Publishing Ltd, 2009. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001447.

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Abstract Lion populations in West and Central Africa are small and fragmented. In areas where park management is weak, threats will likely facilitate the extinction of the lion. Wildlife management requires knowledge of the population estimate. The population of lions in Waza National Park (Waza NP) was assessed by individual identification of members in the population. The population was assessed to comprise of 14–21 adult individual lions. The age structure was skewed towards adults; cubs comprised 22% of all lions identified while the sex ratio was 1 : 3. Two out of four collared lions were lost to illegal, retaliatory killings within 1 year; and probably two more males and one more female were also killed during this period. The lion population appears to have declined during the last 5 years with six lions dying per year, which is at a much higher rate than observed in the previous decades. Human-livestock pressure has increased tremendously in this period, resulting to frequent human-lion conflicts. To ensure the survival of the lion in Waza NP and in the entire region, management needs to intensify efforts to mitigate the pressure from humans and their livestock.

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6

Muhwava, William Betserai. "Fertility decline and determinants of reproductive change in Zimbabwe". Thesis, London School of Hygiene and Tropical Medicine (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300429.

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7

Rafnsson, Snorri Björn. "Cardiovascular diseases, risk factors and cognitive decline in the general population". Thesis, University of Edinburgh, 2007. http://hdl.handle.net/1842/30665.

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The principal aim of the present study was to examine the longitudinal change in cognitive test performance in relation to major clinical CVDs and vascular risk factors in a population-based sample of older people. The analysis is based on a cohort of 809 men and 783 women aged 55-74 years which in 1987/8 was randomly selected from the general population of Edinburgh. The findings from the present study further add to those of previous investigations demonstrating a relationship between CVDs, vascular risk factors, and cognitive decline in older people. Specifically, they reveal that, even in the absence of overt stroke, clinical CVDs are associated with a greater cognitive decline in the elderly, independently of potential confounding by a wide range of vascular risk factors. Also, the relationships between several vascular risk factors and cognitive decline proved to be independent of co-existing vascular pathology. Based on these findings, further study is needed to determine the combined effects of CVDs and multiple risk factors on cognitive outcomes in samples of older people. In addition, what the likely pathological mechanisms are underlying cognitive decline associated with atherosclerotic disease and vascular risk factors risk factors needs to be addressed in future studies. From a perspective of preventing or delaying vascular-based cognitive decline and impairment, more research is required to assess the effectiveness of both individual and population-based strategies targeting vascular disease and risk factors in older age groups. Finally, further investigation is needed to address the potential impact of subtle cognitive deficits on indictors of the quality of life and the capability of self-maintenance of elderly vascular patients, on adherence to medical treatment and rehabilitation, and further cognitive decrements and survival.

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8

Beckley, Julia Ruth. "How Cultural Factors Hastened the Population Decline of the Powhatan Indians". VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1553.

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9

Huldén, Lena. "The decline of northern malaria and population dynamics of Plasmodium vivax". Helsinki University of Helsinki, 2008. http://urn.fi/URN:ISBN:978-951-651-235-1.

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10

Kaugurs, Kristaps. "Urban Shrinkage in Liepāja : Awareness of population decline in the planning process". Thesis, Stockholms universitet, Kulturgeografiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-58898.

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The aim of the study is to investigate the current state of awareness of urban shrinkage inLiepājaby the key actors involved in the planning process. Last couple of hundred years have brought many transformations in urbanity that was always accompanied by the growth of the population and expansion of the city. However, the new patterns of urban development emerged in the last decades all over the globe, causing cities to lose the inhabitants resulting in urban shrinkage.Liepāja, the third largest city inLatvia, has lost a quarter of its population in last two decades and the trend continues. The long-term municipal planning document is being presented during this research in a light of which the research question is asked: “What is the current state of awareness of urban shrinkage inLiepājaby the key actors?” Utilising Flyvbjerg’s phronetic form of inquiry in combination with case study and repeated semi-structured interviews, the dominant planning views related to urban shrinkage are sought and analysed. The research identifies three underlying causalities that shape the decisions in planning and leave formidable consequences for the future of the city. The causalities identified and discussed in this paper are (1) the planning legacy; (2) the misconception; and (3) the political sensitivity of the urban shrinkage.

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11

Proffitt, Fiona M. "Causes of population decline of the bullfinch Pyrrhula pyrrhula in agricultural environments". Thesis, University of Oxford, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.270646.

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12

Treiber, Katherine. "Relationship of Cognitive Reserve and Decline in Alzheimer's Disease: A Population Study". DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/574.

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According to the theory of cognitive reserve, cognitively enriching aspects of life experience (e.g., education, occupation, and leisure activity) foster the development of more efficient neural networks and cognitive strategies, enabling individuals to cope more effectively with the pathology of dementia. Using extant data from a population-based study, we examined: (1) the effect of reserve accrued through middle life on course of neuropsychological decline; and (2) the role of ongoing engagement in mentally stimulating leisure activities in rate of general cognitive and functional deterioration. In linear mixed models, level of occupational attainment did not affect rate of cognitive or functional decline, although women were found to undergo more rapid deterioration in cognitive ability. Occupational skill area was associated with trajectory of decline in several neuropsychological domains. Specifically, vocations emphasizing practical, hands-on skills were associated with slower deterioration in auditory-verbal and visual memory, as well as visuospatial and constructional abilities. Teaching and helping professions, in contrast, were associated with more rapid decline in memory and executive functioning. Increased engagement in cognitive leisure activities through late life was associated with slower deterioration in general cognitive ability in mild dementia, but its effects were no longer evident in more severe AD. An understanding of how rate of decline intersects with patients' past histories and efforts to maintain and enhance cognitive capacity will enable clinicians to target areas for cognitive training and rehabilitative therapy.

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13

Ostrand, William D. "Disease and Habitat Change as Factors Associated with Mourning Dove Population Decline". DigitalCommons@USU, 1995. https://digitalcommons.usu.edu/etd/6516.

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The western mourning dove (Zenaida macroura) population has been declining since 1966. Data collected in 1951-52, in Fillmore, Utah, provided us a baseline for comparison with our study in the same area. Our approach was to determine whether a local population decline had occurred since the original data were collected, assess if trichomoniasis has impacted the local population, determine if changes in habitat structure affect foraging site selection, quantify changes in habitat, identify which habitats doves preferred, ascertain whether doves had responded to habitat change by changing food habits, and assess if changes in habitat were responsible in part for the local population decline. We found that population counts declined 72% and 82% from 1952 to 1992 and 1993, respectively. We determined that trichomoniasis was not an factor. in the decline. We observed that doves preferred foraging habitat characterized by a short and open structure and will not forage in the taller, denser vegetation that now dominates the study area. The most dramatic change in habitat was an 82% decline of land in winter wheat production. In 1951-52 and 1992-93, doves consumed wheat in greater frequency and volume than any other food item. Habitats selected for foraging were wheat fields following harvest, feedpens, hay storage yards, and weedy patches. Of these habitats, area in wheat fields and number of feedpens had changed extensively. The decline in wheat availability, either at harvested fields or feedpens, appears to have contributed to the local population decline. We used regression analysis to test the statewide relationship between the decline in the mourning dove population index, area in winter wheat production, and the number of farms with cattle and obtained significant results (R2 = .42, P = 0.001).

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14

Whitt, Jeffrey Glen. "The Bobwhite Population Decline: Its History, Genetic Consequences, and Studies on Techniques for Locating and Assessing Current Populations". Thesis, University of North Texas, 2019. https://digital.library.unt.edu/ark:/67531/metadc1505132/.

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The northern bobwhite (Colinus virginianus) population decline is a severe, rangewide phenomenon beginning >150 years ago and continuing today. In this investigation, I: 1. document the timeline of bobwhite population decline and unintended genetic consequences of attempted remedies, 2) develop a model useful for predicting possible locations of potentially sustainable bobwhite populations in semiarid rangeland in Texas and Oklahoma, and 3) examine the relationship between population monitoring data and meteorological factors. While breeding season call counts of male bobwhite have been used for >70 years to provide estimates of fall populations for hunting, most studies of call counts have focused on mathematics and statistical accuracy of the count, largely overlooking the influence of meteorological factors on call counts. Here, I present the results of >4,400 individual point counts and examine their relationship with meteorological variables recorded at each stop. Humidity was positively correlated with the number of birds recorded (ρ = 0.275, p < 0.001) and temperature was negatively correlated (ρ = -0.252, p < 0.001). The number of birds recorded was significantly higher in wet years than in drought years. There was no significant correlation between wind velocity and number of birds recorded. These results suggest that, while weather does influence call counts and efforts should be made to record meteorological conditions when collecting call count data, the influence of weather may not easily factor into the analysis. These results also provide another line of evidence for decreased breeding behavior during high temperatures. With the increased focus on bobwhite habitat management on a regional scale, there is a need for reliable methods to identify potential bobwhite habitat. To identify bobwhite habitat in semiarid rangeland, I performed classification of LANDSAT scenes of Clay County, Texas from July and December 2015. Stands of mature little bluestem provide excellent bobwhite nesting cover and could be identified using LANDSAT imagery. I scored habitat by type, compared these scores with the results of breeding season call counts from 2014 and 2015 and found significant correlation. When used in combination with other landscape data, this approach can provide a regional context to inform conservation and management decisions.

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15

Wretenberg, Johan. "The decline of farmland birds in Sweden /". Uppsala : Department of Conservation Biology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/2006113.pdf.

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16

Shephard, Jill, i n/a. "A Multi-Scale Approach to Defining Historical and Contemporary Factors Responsible for the Current Distribution of the White-bellied Sea-Eagle Haliaeetus leucogaster (Gmelin, 1788) in Australia". Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20041012.142221.

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The White-bellied Sea-Eagle Haliaeetus leucogaster is widespread in Australia, but has been the subject of conservation concern due to suggested localised declines and extinctions. Regionalised monitoring programmes have addressed some aspects of local concern, however a broader approach is needed to gain an understanding of large-scale processes affecting long-term persistence at scales equivalent to the species Australian range. Ultimately, the ability to predict change in population size over time accurately depends on the scale of analysis. By necessity, ecological studies using direct sampling techniques are often made across spatial scales smaller than a species geographic range and across relatively short time frames. This seems counter-intuitive considering that long-term species persistence is often dependent on large-scale processes. The principal aim of this thesis was to identify historical and contemporary forces responsible for the current pattern of population structure in H. leucogaster. This required a multi-scale approach, and the resulting research uses genetic, distributional and morphometric data. Haliaeetus leucogaster is a large territorial raptor that historically has been associated with coastal regions, lakes and perennial river systems. It has an extensive worldwide distribution from the western coast of India throughout the Indomalaysian region, Papua New Guinea and Australia. By virtue of the species' large-scale distribution, in Australia it is fairly cosmopolitan in its use of habitat and prey types. Haliaeetus leucogaster is monomorphic for adult plumage colouration, but in body size displays reversed sexual dimorphism with female birds significantly larger. A discriminant function based on 10 morphometric characters was 100% effective in discriminating between 19 males and 18 females that had been sexed using molecular genetic methods. Re-classification using a jackknife procedure correctly identified 92% of individuals. The discriminant function should be a viable alternative to genetic sexing or laparoscopy for a large proportion of individuals within the Australo-Papuan range of this species; and can also be used to identify a small proportion of "ambiguous" individuals for which reliable sexing will require those other techniques. I used mitochondrial (mtDNA) control region sequence data to investigate the current distribution of genetic variation in this species at the continental level and within and between specified regional units. I was specifically interested in identifying breaks in genetic connectivity between the west and east of the continent and between Tasmania and the Australian mainland. Overall, genetic diversity was low and there was no significant level of genetic subdivision between regions. The observed genetic distribution suggests that the population expanded from a bottleneck approximately 160 000 years ago during the late Pleistocene, and spread throughout the continent through a contiguous range expansion. There is insufficient evidence to suggest division of the population into different units for conservation management purposes based on the theoretical definition of the 'evolutionary significant unit'. It is clear from the analysis that there are signatures of both historical and contemporary processes affecting the current distribution. Given the suggestion that population expansion has been relatively recent, additional sampling and confirmation of the perceived pattern of population structure using a nuclear marker is recommended to validate conservation monitoring and management at a continental scale. To determine the existence of perceived population declines across ecological time scales, I analysed the Australian Bird Atlas Data to identify the extent and pattern of change in range and density of the species between three Atlas Periods (1901-1976, 1977-1981 and 1998-2001) using a new standardised frequency measure, the Occupancy Index (OI) for 1° blocks (approx. 100km2) across the continent. At the continental scale, there was no significant difference in the spatial extent of occupancy between Atlas Periods. However, there were considerable changes in frequency and range extent between defined regions, and there were distinct differences in the pattern of change in OI between coastal and inland blocks over time. Coastal blocks showed much more change than inland blocks, with a clear increase in the use of coastal blocks, accompanied by a decrease in inland blocks, during the 1977-1981 Atlas Period, relative to both other Atlas Periods. The over-riding factor associated with distributional shifts and frequency changes was apparently climatic fluctuation (the 1977-1981 period showing the influence of El Nino associated drought). The impression of abundance was strongly dependent on both the temporal and spatial scale of analysis. To test for correspondence between geographic variation in morphology and geographic variation in mtDNA I analysed morphometric data from 95 individuals from Australia and Papua New Guinea. First, the degree of morphometric variation between specified regions was determined. This was then compared with the pattern of genetic differentiation. There was a strong latitudinal cline in body dimensions. However, there was no relationship between morphometric variation and patterns of genetic variation at least for mtDNA. Females showed a pattern of isolation by distance based on morphometric characters whereas males did not. Three hypotheses to explain the pattern of morphometric variation were considered: phenotypic plasticity, natural selection and secondary contact between previously isolated populations. I conclude that the pattern of morphometric variation is best explained by the suggestion that there is sufficient local recruitment for natural selection to maintain the observed pattern of morphometric variation. This implies that gene flow may not be as widespread as the mtDNA analysis suggested. In this instance either the relatively recent colonisation history of the species or the inability of the mtDNA marker to detect high mutation rates among traits responsible for maintaining morphometric variation may be overestimating the levels of mixing among regions. As might be expected given the physical scale over which this study was conducted, the pattern of genetic, morphometric and physical distribution varied dependent on the scale of analysis. Regional patterns of genetic variation, trends in occupancy and density and morphometric variation did not reflect continental patterns, reinforcing the contention that extrapolation of data from local or regional levels is often inappropriate. The combined indirect methodologies applied in this study circumvent the restrictions imposed by direct ecological sampling, because they allow survey across large geographic and temporal scales effectively covering the entire Australian range of H. leucogaster. They also allow exploration of the evolutionary factors underpinning the species' current distribution.

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17

Shephard, Jill. "A Multi-Scale Approach to Defining Historical and Contemporary Factors Responsible for the Current Distribution of the White-bellied Sea-Eagle Haliaeetus leucogaster (Gmelin, 1788) in Australia". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/367440.

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The White-bellied Sea-Eagle Haliaeetus leucogaster is widespread in Australia, but has been the subject of conservation concern due to suggested localised declines and extinctions. Regionalised monitoring programmes have addressed some aspects of local concern, however a broader approach is needed to gain an understanding of large-scale processes affecting long-term persistence at scales equivalent to the species Australian range. Ultimately, the ability to predict change in population size over time accurately depends on the scale of analysis. By necessity, ecological studies using direct sampling techniques are often made across spatial scales smaller than a species geographic range and across relatively short time frames. This seems counter-intuitive considering that long-term species persistence is often dependent on large-scale processes. The principal aim of this thesis was to identify historical and contemporary forces responsible for the current pattern of population structure in H. leucogaster. This required a multi-scale approach, and the resulting research uses genetic, distributional and morphometric data. Haliaeetus leucogaster is a large territorial raptor that historically has been associated with coastal regions, lakes and perennial river systems. It has an extensive worldwide distribution from the western coast of India throughout the Indomalaysian region, Papua New Guinea and Australia. By virtue of the species' large-scale distribution, in Australia it is fairly cosmopolitan in its use of habitat and prey types. Haliaeetus leucogaster is monomorphic for adult plumage colouration, but in body size displays reversed sexual dimorphism with female birds significantly larger. A discriminant function based on 10 morphometric characters was 100% effective in discriminating between 19 males and 18 females that had been sexed using molecular genetic methods. Re-classification using a jackknife procedure correctly identified 92% of individuals. The discriminant function should be a viable alternative to genetic sexing or laparoscopy for a large proportion of individuals within the Australo-Papuan range of this species; and can also be used to identify a small proportion of "ambiguous" individuals for which reliable sexing will require those other techniques. I used mitochondrial (mtDNA) control region sequence data to investigate the current distribution of genetic variation in this species at the continental level and within and between specified regional units. I was specifically interested in identifying breaks in genetic connectivity between the west and east of the continent and between Tasmania and the Australian mainland. Overall, genetic diversity was low and there was no significant level of genetic subdivision between regions. The observed genetic distribution suggests that the population expanded from a bottleneck approximately 160 000 years ago during the late Pleistocene, and spread throughout the continent through a contiguous range expansion. There is insufficient evidence to suggest division of the population into different units for conservation management purposes based on the theoretical definition of the 'evolutionary significant unit'. It is clear from the analysis that there are signatures of both historical and contemporary processes affecting the current distribution. Given the suggestion that population expansion has been relatively recent, additional sampling and confirmation of the perceived pattern of population structure using a nuclear marker is recommended to validate conservation monitoring and management at a continental scale. To determine the existence of perceived population declines across ecological time scales, I analysed the Australian Bird Atlas Data to identify the extent and pattern of change in range and density of the species between three Atlas Periods (1901-1976, 1977-1981 and 1998-2001) using a new standardised frequency measure, the Occupancy Index (OI) for 1° blocks (approx. 100km2) across the continent. At the continental scale, there was no significant difference in the spatial extent of occupancy between Atlas Periods. However, there were considerable changes in frequency and range extent between defined regions, and there were distinct differences in the pattern of change in OI between coastal and inland blocks over time. Coastal blocks showed much more change than inland blocks, with a clear increase in the use of coastal blocks, accompanied by a decrease in inland blocks, during the 1977-1981 Atlas Period, relative to both other Atlas Periods. The over-riding factor associated with distributional shifts and frequency changes was apparently climatic fluctuation (the 1977-1981 period showing the influence of El Nino associated drought). The impression of abundance was strongly dependent on both the temporal and spatial scale of analysis. To test for correspondence between geographic variation in morphology and geographic variation in mtDNA I analysed morphometric data from 95 individuals from Australia and Papua New Guinea. First, the degree of morphometric variation between specified regions was determined. This was then compared with the pattern of genetic differentiation. There was a strong latitudinal cline in body dimensions. However, there was no relationship between morphometric variation and patterns of genetic variation at least for mtDNA. Females showed a pattern of isolation by distance based on morphometric characters whereas males did not. Three hypotheses to explain the pattern of morphometric variation were considered: phenotypic plasticity, natural selection and secondary contact between previously isolated populations. I conclude that the pattern of morphometric variation is best explained by the suggestion that there is sufficient local recruitment for natural selection to maintain the observed pattern of morphometric variation. This implies that gene flow may not be as widespread as the mtDNA analysis suggested. In this instance either the relatively recent colonisation history of the species or the inability of the mtDNA marker to detect high mutation rates among traits responsible for maintaining morphometric variation may be overestimating the levels of mixing among regions. As might be expected given the physical scale over which this study was conducted, the pattern of genetic, morphometric and physical distribution varied dependent on the scale of analysis. Regional patterns of genetic variation, trends in occupancy and density and morphometric variation did not reflect continental patterns, reinforcing the contention that extrapolation of data from local or regional levels is often inappropriate. The combined indirect methodologies applied in this study circumvent the restrictions imposed by direct ecological sampling, because they allow survey across large geographic and temporal scales effectively covering the entire Australian range of H. leucogaster. They also allow exploration of the evolutionary factors underpinning the species' current distribution.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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18

Moorcroft, Darren. "The causes and decline of the linnet Carduelis cannabina within the agricultural landscape". Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365717.

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19

Hedlund, Martin. "Growth and decline in rural Sweden : geographical distribution of employment and population 1960–2010". Doctoral thesis, Umeå universitet, Kulturgeografi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-139723.

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This thesis investigates the combination of changes in the population and employment into sectors in rural Sweden for the period 1960-2010. The aim is to describe and analyze the demographic changes together with the labour market changes, and to account for the spatial outcome of these changes by considering the heterogeneity of rural areas. The analysis departs from the framework of rural restructuring, where changes in employment and population in rural Sweden are interpreted as local products of the global processes of technological development, social modernization and globalization. Empirically, the analysis is based on a combination of longitudinal censuses and register data on the Swedish population covering the period 1960-2010. The first part of the aim is achieved by applying a life-course perspective and exploiting the longitudinal nature of the data. The life-course perspective distinguishes between historical time and the age of individuals, making it possible to situate changes in employment and migration on the individual level. The second part of the aim is achieved through developing a typology of rural Sweden by doing a cluster analysis on SAMS-areas. The results show that rural change after 1980 was characterized by de-industrialization and the rise of the urban service sector. The period was also characterized by regional urbanization rather than local urbanization. Peripheral urban and rural areas based on industrial employment found themselves with a declining economic motor, which meant that people had to find their source of income elsewhere. The migration stream in this period was thus increasingly directed towards metropolitan or large city centers, and their rural surroundings within commuting distance. However, the more fine-tuned spatial typology reveals that also a few areas in the rural periphery have experienced growth, these areas are mainly attractive places based on various kinds of tourism. It can thus be concluded that different rural areas have experienced, and will continue to experience, the shift from manufacturing to services differently, where some areas have grown in both demographic and employment terms while others have declined. In this sense the heterogeneity of rural areas are a product of both growth and decline – of old development paths that is reaching their end and of new development paths that will continue into the future.

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20

Lutz, Wolfgang, i Samir KC. "Dimensions of global population projections: what do we know about future population trends and structures?" The Royal Society, 2010. http://dx.doi.org/10.1098/rstb.2010.0133.

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The total size of the world population is likely to increase from its current 7 billion to 8-10 billion by 2050. This uncertainty is because of unknown future fertility and mortality trends in different parts of the world. But the young age structure of the population and the fact that in much of Africa and Western Asia, fertility is still very high makes an increase by at least one more billion almost certain. Virtually, all the increase will happen in the developing world. For the second half of the century, population stabilization and the onset of a decline are likely. In addition to the future size of the population, its distribution by age, sex, level of educational attainment and place of residence are of specific importance for studying future food security. The paper provides a detailed discussion of different relevant dimensions in population projections and an evaluation of the methods and assumptions used in current global population projections and in particular those produced by the United Nations and by IIASA.

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21

Nash, James. "Aspects of a town in decline : a population study of Burford, Oxfordshire, 1851-1901". Thesis, University of Oxford, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442940.

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22

Sharma, Surender K. "The decline of the roe deer (Capreolus capreolus L.) in the New Forest, Hampshire". Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.295232.

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23

Kebede, Endale Birhanu, Anne Goujon i Wolfgang Lutz. "Stalls in Africa's fertility decline partly result from disruptions in female education". The National Academies of Sciences, Engineering, and Medicine, 2019. http://dx.doi.org/10.1073/pnas.1717288116.

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Population projections for sub-Saharan Africa have, over the past decade, been corrected upwards because in a number of countries, the earlier declining trends in fertility stalled around 2000. While most studies so far have focused on economic, political, or other factors around 2000, here we suggest that in addition to those period effects, the phenomenon also matched up with disruptions in the cohort trends of educational attainment of women after the postindependence economic and political turmoil. Disruptions likely resulted in a higher proportion of poorly educated women of childbearing age in the late 1990s and early 2000s than there would have been otherwise. In addition to the direct effects of education on lowering fertility, these less-educated female cohorts were also more vulnerable to adverse period effects around 2000. To explore this hypothesis, we combine individual-level data from Demographic and Health Surveys for 18 African countries with and without fertility stalls, thus creating a pooled dataset of more than two million births to some 670,000 women born from 1950 to 1995 by level of education. Statistical analyses indicate clear discontinuities in the improvement of educational attainment of subsequent cohorts of women and stronger sensitivity of less-educated women to period effects. We assess the magnitude of the effect of educational discontinuity through a comparison of the actual trends with counterfactual trends based on the assumption of no education stalls, resulting in up to half a child per woman less in 2010 and 13 million fewer live births over the 1995-2010 period.

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Carpenter, Jane. "An investigation of causes of population decline in the marsh tit poecile palustris in Britain". Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496836.

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Buckley, Trevor. "Measuring Unawareness of Cognitive Decline in a Population of Elderly Individuals: The Cache County Study". DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/67.

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The metacognitive skills of elderly individuals were examined using a brief, seven-item questionnaire. The construct validity of the questionnaire was examined using two forms of external criteria, the Modified Mini-Mental State Exam (3MS), and informant reports of functional ability. Analysis of Cronbach’s alpha coefficients suggested moderate levels of internal consistency for the questionnaire (alpha = .75). Factor analysis (principal components) revealed two factors, one functional and one cognitive. Multiple regression analyses demonstrated that the metacognition questionnaire did not significantly predict 3MS change over a 3-year interval. Logistic regression analyses demonstrated that the metacognition questionnaire significantly predicted informant ratings. The metacognition questionnaire differentially predicted both outcome scores within dementia and no-dementia subgroups. These results provide support for the construct validity of the questionnaire. Future studies will examine the efficacy of brief questionnaires to measure unawareness in the elderly and continue to examine the differences in unawareness between demented and nondemented individuals.

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Pacioni, Carlo. "The population and epidemiological dynamics associated with recent decline of woylies (Bettongia penicillata) in Australia". Thesis, Pacioni, Carlo (2010) The population and epidemiological dynamics associated with recent decline of woylies (Bettongia penicillata) in Australia. PhD thesis, Murdoch University, 2010. https://researchrepository.murdoch.edu.au/id/eprint/4359/.

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The woylie or brush‐tailed bettong (Bettongia penicillata ogilbyi) has recently undergone a dramatic decline (approximately 80% between 2001 and 2006). The Woylie Conservation and Research Project (WCRP) was established to investigate possible causes of this decline. It was hypothesised that predators and/or a disease may be a concomitant cause if not the primary cause(s) of the decline, based on the peculiar temporal and spatial characteristics of the decline and available associative evidence. This research project is an integrated and collaborative component of the WCRP and its broad aim was to contribute to the knowledge on the general health and ecological attributes of woylie populations that were considered directly relevant for the conservation and recovery of the species. Initially, the WCRP in collaboration with several researchers supported the investigation of specific pathogens. These projects were ongoing when the research described in this thesis began, however there had been no disease risk assessment prior to these ongoing pathogen studies. Therefore, a formal qualitative assessment of the disease risks potentially relevant to the woylie declines was undertaken in this study to ensure a systematic evaluation and to prioritise allocation of resources. Several pathogens were identified as a high priority for further investigation including, but not limited to, Macropod Herpesvirus (MaHV), Macropod Orbivirus (Wallal and Warrego serogroups), and Encephalomyocarditis virus (EMCV). A haematological investigation was carried out and reference ranges were established. An overall increase of the leukocytic response in animals trapped in Upper Warren (8%, n=23) compared to woylies in Karakamia (0%) was demonstrated. Gender differences were also recorded, namely males had higher red blood cell, white blood cell and lymphocyte counts than females. No clear evidence was found that supported an association between changes in the health status of woylies and the decline. Nevertheless, the increased proportion of lymphocytosis (p<0.0005) in Perup, which includes two forest blocks that underwent a decline during sample collection, and the higher prevalence of health problems identified during the physical examinations of animals trapped in Upper Warren (41.3%, n=557) as compared to those from Karakamia (10%, n=80, p<0.0005. Odds Ratio=6.33, 95% CI 2.99‐13.40), justified further disease investigations. Based on the results of the disease risk assessment and haematological analysis, the serological response to Macropod Herpesvirus (MaHV 1 and 2), Encephalomyocarditis virus (EMCV) and Orbivirus (Wallal and Warrego serogroups) was investigated. There was no serological evidence of any of these viruses affecting woylie populations. Nevertheless, due to sample size limitations, it was not possible to confirm the absence of these diseases with a high level of confidence (i.e. >90%). Additionally, the absence of detection of seropositive individuals does not necessarily imply absence of the pathogen in the population. Genetic profiles of indigenous (extant wild populations) and translocated woylie populations were examined in order to assess whether woylie populations were suffering from a reduced genetic “health”, as a consequence of the bottleneck that occurred after European settlement. In order to do this a preliminary investigation of the cross‐species performance of 32 primer pairs was carried out to assess their suitability for the aims of this study. Twelve microsatellite primer sets were identified as polymorphic and reliable for genetic analysis in woylie. Additionally, the cross‐species performance of the 32 primer pairs was analysed within the potoroines species to facilitate future ecological and genetic studies in bettongs and potoroos. A 50% reduction in amplification success of polymorphic loci for every 1 million years of evolutionary distance from taxa was found and a “priority‐list” of markers for use in potoroines was identified. Genetics does not appear to be a contributing factor to the present woylie decline. Expected heterozygosity (HE) was around 80%, ranging from 42.3% to 83.6% and the allelic richness (NAR) was around 6, ranging from 2.67 to 9.72. Nevertheless, among the indigenous populations particular concern was raised for woylies at Tutanning Nature Reserve, and for the translocated populations on the South Australian islands. These populations have a substantially reduced genetic diversity (Tutanning: HE = 0.64; St Peter island: HE = 0.631; Wedge island: HE = 0.602; Venus Bay island “A”: HE = 0.423). Important insights were gained into woylie population structure and dynamics through the analysis of molecular data. Four genetically distinct indigenous populations were identified (i.e. Dryandra woodland and Tutanning Nature Reserve in the wheatbelt region and two discrete populations in the Upper Warren in the south‐west forests of Western Australia). The mtDNA analysis showed historical connections between populations in Dryandra and the Upper Warren region (Kingston and Perup). These connections no longer exist as a result of habitat fragmentation caused by agriculture and farming land use. Additionally, substantial gene flow was identified between Kingston and Perup and was supported and quantified by microsatellite analyses in the order of 2‐3% migration rate. The evidence of current gene flow within and between populations (i.e. up to 60 km) signifies that direct transmission of an aetiological agent would be possible throughout the whole Upper Warren region within the time frame experienced in the decline. Analysis of genetic data indicated also that the woylie population in Kingston had already undergone a decline. As a consequence of this change in population abundance, the spatial genetic structure of this population changed, generating a significant correlogram up to 6 km. In other words, in this population, two woylies trapped within a radius of 6 km are likely to be related as opposed to other populations where the genetic signal drops between 1 and 3 km. Additionally, and consistent with previous ecological studies, female philopatry was confirmed and genetic consequences of this behaviour were identified. Population viability analysis (PVA) demonstrated that the main threatening process for woylie populations is the result of the interaction of various variables (in particular predation and inbreeding) that acquire a considerable strength together, whilst not being greatly significant by themselves. It also quantified the minimum mortality rates necessary for the decline to occur (an average juvenile and subadult mortality rate of 28% and 22% for adults per 91 day time period). The minimum viable population size (MVP) estimated through PVA was consistent with the empirical evaluation based on molecular data (i.e. 1,000‐2,000 individuals). As a consequence of the inherent inability of satisfactorily predicting stochastic events and incomplete knowledge on important factors that may affect population size a conservative approach should be adopted. On this basis, a population size of more than 8,000 individuals should be targeted to maximise the likelihood of positive conservation outcomes. In light of the results of this research project, disease can not be completely dismissed as a possible cause of decline, in particular in association with predation. Haematological, serological and genetic information generated by this study greatly improved the available knowledge on the health and viability of woylie populations and represent baseline data that will enable monitoring and detection of changes in the health status in these populations, as well as contribute to the refinement of the disease risk assessment and quarantine protocols. The haematological data will also facilitate and improve the interpretation of disease investigations carried out by the additional collaborative components of the WCRP. Moreover, information obtained on woylie ecology through the analysis of genetic molecular data will assist such interpretations, for example by conveying indications on the frequency and extent of animal movements. This research also provided suggestions for critical management decisions. For example, the identification of woylie populations at risk of substantial loss of genetic diversity and possibly inbreeding depression calls for appropriate management actions. Where there is no indication of any factor limiting the demographic growth of the populations (i.e. populations on South Australian islands) supplementation was identified as the most suitable management option. Based on the detailed knowledge obtained on the spatial organization of woylie populations, it is now possible to adequately source animals from indigenous populations to augment genetic diversity. Animals should be trapped at a distance of at least 1‐3 km in order to maximise the probability that individuals are unrelated. On the other hand, it is critical to identify the causes currently limiting population growth prior to the implementation of these management actions, especially where limited population size (in respect to the carrying capacity) and consequent genetic drift is the main reason for the poor genetic profile of the population rather than isolation. The PVA also helped to determine critical requirements for the establishment of new, and maintenance of, populations; more specifically that sites should be able to support a minimum population size of 8,000 individuals and that the average mortality rate should be maintained below 22% for juveniles and 28% for adults per 91 day period. Finally, this research helped to identify important future areas of investigation. These include longitudinal studies of the health status of individual woylies; epidemiological analysis of the data generated by this study integrated with those generated by other WCRP researchers and a quantification of the influence of ecological factors, such as rainfall and diet, on general health parameters. Additionally, regular genetic monitoring is recommended because the baseline data produced in this study and the associated ecological and demographic data available would provide an optimal opportunity to improve our understanding of genetic consequences of rapid population declines. This monitoring may help to quantify the genetic loss associated with the decline and evaluate the accuracy of PVA predictions. It might be possible to assess the success of management actions (e.g. supplementations) and detect if and when inbreeding depression becomes manifest in populations at lower genetic diversity (e.g. Tutanning). In addition, the molecular genetic data represents the background work needed to establish the interplay between individual (host) genetic profile and disease susceptibility or fitness (including fecundity and survival). The fact that cross‐species primers were used would make the utility of the knowledge acquired easily and directly applicable to other species of the superfamily Macropodoidae.

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Eriksson, Linnéa. "Planering och strategier för krympande kommuner : en fallstudie om hur befolkningsminskningar hanteras i kommunal planering". Thesis, Blekinge Tekniska Högskola, Institutionen för fysisk planering, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-12648.

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Sveriges befolkning ökar i helhet och storstadsregionerna växer genom en stark urbaniseringstrend. Som en effekt av detta krymper nästan hälften av Sveriges kommuner sett till antal invånare. En minskad befolkning kan ge minskad ekonomisk tillväxt samt ge kommunerna problem att erbjuda service av hög kvalitet till sina invånare. Befolkningsminskningarna beror ofta på utflyttningar, låga födelsetal i kombination med att befolkningen blir allt äldre vilket leder till att det i många fall blir allt färre som ska försörja allt fler. En krympande befolkning är ofta ett känsligt ämne att tala öppet om, det finns en rädsla att kommunen ska framstå som oattraktiv om den förknippas med utflyttningar och befolkningsminskning, samtidigt som en kraftig befolkningsminskning är en aktuell förutsättning för många svenska kommuner. Syftet är att genom en kvalitativ undersökning av två fall se hur olika svenska kommuner hanterar en befolkningsminskning. De frågeställningar som behandlas är: - Vad finns det för strategier för hur krympande kommuner kan hanteras i planeringen enligt forskningen? - Hur hanterar svenska kommuner en befolkningsminskning, vilka strategier används? - Överensstämmer kommunernas arbete med forskningen? De dokument som analyserats har avgränsats till kommunala översiktsplaner för att få en förståelse för hur den svenska planeringen hanterar befolkningsminskningar eftersom de är långsiktiga strategiska dokument där kommunens politiker för fram sina visioner för kommunens utveckling och framtida markanvändning. Forskningen kring ämnet skiljer på anpassningsstrategier och tillväxtstrategier och det framgår att det i många fall för krympande kommuner kunde vara lämpligt att fokusera på anpassning istället för tillväxt. De strategier som kunnat hittas genom en forskningsöversikt har varit det teoretiska ramverket för uppsatsen. I arbetet har forskningsöversiktens strategier använts i en kvalitativ innehållsanalys av två kommunala översiktsplaner för att se vilka strategier som används och vilka som inte används. Viktiga resultat är att de svenska kommunerna främst fokuserar på tillväxtstrategier men även vissa anpassningsstrategier. Detta stämmer väl överens med hur forskningen beskriver läget nationellt och internationellt men forskningen föreslår ett paradigmskifte mot en samhällsutveckling i form av anpassning skulle gynna många av de krympande områdena bättre.
The Swedish population is growing but the growth is only occurring in regions with bigger cities because of the fast urbanisation. Over half of the counties in the country is losing population due to outmigration, low fertility rates and an ageing population, leaving a few to support a growing group of seniors. The population decline can lead to a lack of economic growth and that the counties have trouble providing high quality service to its inhabitants. The aim with the study is to examine how Swedish counties cope with demographic decline through case studies. The thesis examines the following research questions: - What strategies can be adopted by shrinking cities according to planning research? - How do shrinking counties in Sweden cope with population decline? - Is the Swedish way of coping matching up with the research? A qualitative content analysis has been used to find what strategies can be found in two Swedish master plans. Important results from the study is that the counties are focused on growth oriented strategies but do use some forms of adaption. This focus on growth matches with the findings in contemporary research in the field of shrinking cities that suggest a paradigm shift towards smart decline and a focus on adaption for the shrinking areas.

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You, Benoît. "Dynamic analysis of serum tumor marker decline during anti-cancer treatment using population kinetic modeling approach". Phd thesis, Université Claude Bernard - Lyon I, 2011. http://tel.archives-ouvertes.fr/tel-00848364.

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Several cancers are associated with abnormal serum concentrations of tumor markers such as prostate specific antigen (PSA) in prostate tumor diseases, alfa-fetoprotein (AFP) or human chorionic gonadotrophin (hCG) in germ cell tumors or persistent gestational trophoblastic diseases (GTD). Cancer treatment should induce decline of serum tumor marker concentrations. The predictive values of many kinetic parameters supposed to characterize tumor marker declines such as nadir, time-point cutoff, half-life, time to normalization etc..., have been reported in previous studies. However very few of them have been used in routine due to the lack of outcome reproducibility. Population pharmacokinetic approach-based modeling is already used in pharmacokinetic studies. It might be helpful to characterize tumor marker decline equations dynamically and overcome limitations of previous studies. The feasibility and the relevance of this approach were assessed in 4 studies involving: PSA titers in patients with prostate adenoma or cancer treated with surgery; hCG-AFP in non-seminomatous germ cell tumor patients treated with BEP regimen (Bleomycin-Etoposide-Cisplatin) and hCG in GTD patients treated with methotrexate. Tumor marker decline modeling was feasible in all studies provided the methodology was adjusted to marker specificities. Apparent clearance of hCG and PSA might enable identification of patients with unfavorable decline profiles and thereby with high risk of relapse. Confirmatory studies with independent cohorts of patients are warranted

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Vincent, Kate E. "Investigating the causes of the decline of the urban house sparrow Passer domesticus population in Britain". Thesis, De Montfort University, 2005. http://hdl.handle.net/2086/10742.

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In Britain and parts of northwest Europe, House Sparrow Passer domesticus populations have declined markedly in urban-suburban landscapes since the mid-1980s. Little is known about the demographic mechanisms or environmental causes of these population declines, although lack of winter seed has been implicated as a cause of the decline in House Sparrow numbers on English farmland (Hole, 2001). This study focused on factors affecting nesting success and annual productivity of nesting House Sparrows along an urban-suburban-rural gradient centred on the city of Leicester, England. Chick diet (inferred from faecal remains), habitat selection by foraging adults and over-winter survival were also studied. Data were collected during 2001-2003 from 9 study areas spread along the urbanisation gradient. Most sparrows in most study areas nested in or close to domestic gardens. Counts of territorial males declined by 28% between 2001 and 2003, with the largest declines in rural villages (25%) and suburban fringe (16%) and a small increase (4%) in the urban centre. Annual productivity (the estimated number of fledged young/pair/year) was 25% lower in suburban areas and 18% lower in rural areas than that measured during a recent study of farmland House Sparrows in Oxfordshire. The main cause of this lower productivity was starvation of chicks, (usually the first 5-6 days after hatching) during June and July. Chicks were more likely to starve if their diet contained a high proportion of vegetable material (mainly supplementary food) or ants, and less likely to starve if their diet contained a high proportion of spiders. The number of young sparrows successfully fledging, and the aggregate chick biomass, per nesting attempt were greater in home ranges containing relatively high proportions of deciduous shrub, trees and grass, and relatively little concrete. During June and July 2003, more young fledged from home ranges containing a higher density of aphids. Dipteran prey (Tipulids and other flies) constituted a higher proportion of the chick diet in rural localities than in urban-suburban localities, while Homopteran prey (mainly aphids) constituted a higher proportion of chick diet in urban-suburban localities. After allowing for effects of weather, nestling body mass and condition were negatively correlated to local levels of nitrogen dioxide air pollution. Since body mass at fledging is known to be a good predictor of immediate post-fledging survival, I predicted that the lower average body mass at fledging among suburban broods (compared to rural broods) would result in lower survival during the first 10 days after fledging (57% for suburban fledglings, compared to 70% for rural fledglings). The combined effects of lower annual productivity and lower predicted post-fledging survival in suburban localities were large enough to result in rapid predicted population decline, given plausible annual survival rates of adults and first-year sparrows and no net immigration. Under the same set of assumptions, productivity and predicted postfledging survival were high enough in rural localities to maintain and even increase adult population size. Deciduous shrubbery, grassy areas and concrete were the main summer foraging habitats of suburban and rural House Sparrows, with trees being heavily utilised in 2003. Ornamental and evergreen shrubs were strongly avoided by foraging sparrows. Stable isotope ratios of nitrogen (δ¹⁵N scores) in chick feathers are proposed to constitute a useful integrated measure of the quality of the chick diet. δ¹⁵N scores differed markedly between the vegetable (2.7), herbivorous invertebrate (4.7-6.4) and carnivorous invertebrate (7.1-7.7) components of chick diet. δ¹⁵N scores in sparrow chick feathers averaged 7.7 suggesting that the average δ¹⁵N score of ingested diet was approximately 4.7 (i.e. was probably dominated by vegetable material and herbivorous invertebrates). Feather δ¹⁵N scores were lower in home ranges containing relatively large areas of concrete and evergreen vegetation, and were a positive predictor of chick growth rate and body condition. The data presented in this thesis suggest that the abundance of invertebrate prey within home ranges of House Sparrows breeding within suburban and rural garden habitats limits the quantity and quality of chicks raised to fledging. The combined effects of relatively high rates of chick starvation and low body masses at fledging (and consequently low post-fledging survival) observed in suburban localities are large enough to result in rapid population declines. Invertebrate abundance in suburban areas is probably determined, at least in part, by the availability of suitable habitat including native deciduous shrubbery, tress and grassland. Although there is no evidence that the abundance of key invertebrate prey have declined in urban-suburban landscapes, such declines do provide a plausible mechanism for the observed declines in urban-suburban House Sparrow populations. Management techniques, which increase densities of key invertebrate prey during summer, have the potential to increase the annual productivity and possibly the breeding densities of House Sparrows in urban-suburban landscapes.

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Perkins, Allan John. "Causes of decline and conservation solutions for Corn Buntings Emberiza calandra in eastern Scotland". Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7764.

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The Corn Bunting Emberiza calandra is one of the most severely declining farmland birds across Europe. In the UK, numbers fell by 86% between 1967 and 2008. Corn Buntings favour open landscapes, nest on or close to the ground, are often polygynous, double-brooded, and have a seed-based diet supplemented in summer by invertebrates. This study investigated the recent causes of decline in arable and mixed farmland in eastern Scotland, and sought to identify potential conservation solutions that could be delivered through agri-environment schemes (AES). Combining new data with analyses of existing long-term datasets, I investigated habitat associations during summer and winter, the timing and success of nesting attempts, and measured reproductive and population responses to AES. Corn Buntings declined almost to extinction in one study area where, over 20 years, the main recorded intensifications of farming were reduced weed abundance within crops and removal of boundaries to make bigger fields. Territory locations, late-summer occupancy and polygyny were all strongly associated with weedy fields. There were also positive associations with overhead wires and in early summer with winter barley and forage grasses. Late-summer occupancy was associated with spring-sown cereals, crops that are amongst the last to be harvested. Changes in habitat associations and to aspects of the mating system as the population declined and agriculture intensified are discussed. Intensive monitoring showed that Corn Buntings laid clutches from mid-May to mid-August, mostly in fields of forage grasses and autumn-sown cereals in early summer, and spring sown cereals in late summer. A preference for nesting in dense swards explained this seasonal variation. Breeding success in forage grasses was poor, due to high rates of nest loss during mowing. However, in experimental trials, nest success in fields with delayed mowing was fivefold that of control fields. With sufficient uptake through AES, delayed mowing could raise productivity to levels required to reverse population declines. In winter, cereal stubbles and AES unharvested crop patches were the main foraging habitats used. Unharvested crops with abundant cereal grain in their first winter of establishment were favoured. Population monitoring over seven years and 71 farms revealed increases on farms with AES targeted at Corn Buntings, no significant change on farms with general AES, and declines on control farms. In arable-dominated farmland, management that increased food availability reversed declines, but on mixed farmland where Corn Buntings nested in forage grasses, delayed mowing was essential for population increase. This study has already influenced the design of AES targeted at Corn Buntings in Scotland, and I make further recommendations for the species’ conservation and design of AES that are applicable to farmland throughout Britain and Europe.

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Rouanet, Anais. "Study of dementia and cognitive decline accounting for selection by death". Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0243/document.

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Ce travail a pour but de développer des outils statistiques pour l'étude du déclin cognitif général ou précédant le diagnostic de démence, à partir de données de cohorte en tenant compte du risque compétitif de décès et de la censure par intervalle. Le temps de démence est censuré par intervalle dans les études de cohortes car le diagnostic de démence ne peut être établi qu'à l'occasion des visites qui peuvent être espacées de plusieurs années. Ceci induit une sous-estimation du risque de démence à cause du risque compétitif de décès : les sujets déments sont à fort risque de mourir, et peuvent donc décéder avant la visite de diagnostic. Dans la première partie, nous proposons un modèle conjoint à classes latentes pour données longitudinales corrélées à un événement censuré par intervalle, en compétition avec le décès. Appliqué à la cohorte Paquid, ce modèle permet d'identifier des profils de déclin cognitif associés à des risques différents de démence et de décès. En utilisant cette méthodologie, nous comparons ensuite des modèles pronostiques dynamiques pour la démence, traitant la censure par intervalle, basés sur des mesures répétées de marqueurs cognitifs. Dans la seconde partie, nous conduisons une étude comparative afin de clarifier l'interprétation des estimateurs du maximum de vraisemblance des modèles mixtes et conjoints et estimateurs par équations d'estimation généralisées (GEE), couramment utilisés dans le contexte de données longitudinales incomplètes et tronquées par le décès. Les estimateurs de maximum de vraisemblance ciblent le changement individuel chez les individus vivants. Les estimateurs GEE avec matrice de corrélation de travail indépendante, pondérés par l'inverse de la probabilité d'être observé sachant que le sujet est vivant, ciblent la trajectoire moyennée sur la population des survivants à chaque âge. Ces résultats justifient l'utilisation des modèles conjoints dans l'étude de la démence, qui sont des outils prometteurs pour mieux comprendre l'histoire naturelle de la maladie
The purpose of this work is to develop statistical tools to study the general or the prediagnosis cognitive decline, while accounting for the selection by death and interval censoring. In cohort studies, the time-to-dementia-onset is interval-censored as the dementia status is assessed intermittently. This issue can lead to an under-estimation of the risk of dementia, due to the competing risk of death: subjects with dementia are at high risk to die and can thus die prior to the diagnosis visit. First, we propose a joint latent class illness-death model for longitudinal data correlated to an interval-censored time-to-event, competing with the time-to-death. This model is applied on the Paquid cohort to identify profiles of pre-dementia cognitive declines associated with different risks of dementia and death. Using this methodology, we compare dynamic prognostic models for dementia based on repeated measures of cognitive markers, accounting for interval censoring. Secondly, we conduct a simulation study to clarify the interpretation of maximum likelihood estimators of joint and mixed models as well as GEE estimators, frequently used to handle incomplete longitudinal data truncated by death. Maximum likelihood estimators target the individual change among the subjects currently alive. GEE estimators with independent working correlation matrix, weighted by the inverse probability to be observed given that the subject is alive, target the population-averaged change among the dynamic population of survivors. These results justify the use of joint models in dementia studies, which are promising statistical tools to better understand the natural history of dementia

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Chen, Haili. "Developing the adaptation strategy for a population decline Japan: in preparation of the Tokai-Tonankai-Nankai Earthquake". 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/131881.

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Demers, Alanna. "They Kill Horses, Don't They? Peasant Resistance and the Decline of the Horse Population in Soviet Russia". Bowling Green State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1459521486.

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Levy, Foster, i Elaine S. Walker. "Pattern and Rate of Decline of a Population of Carolina Hemlock (Tsuga caroliniana Engelm.) in North Carolina". Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/707.

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We monitored a population of Carolina Hemlocks in northwestern North Carolina for four years to examine the rate and pattern of decline in response to infestation by Adelges tsugae (Hemlock Woolly Adelgid). Our yearly census of hemlock condition and severity of the adelgid infestation included trees of all sizes. We estimated declines in condition as the portions of the leaf canopy that were lost. Initially, infestation occurred throughout the population but was severe in only a small cluster of individuals. Within 1 year, the area of severe infestation increased in size to encompass 48% of the population. In another region of the population, there was a cluster of relatively healthy individuals comprised largely of seedlings. Of the 4 size-classes of trees, sapling-sized individuals experienced the highest rates of decline in condition. Most trees declined to poor health within 3 years of an observation of moderate to severe infestation.

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Ecklar, Brooke Irene. "Evaluating Migratory Stopover Success: Monitoring the Decline of Bird Populations at Hueston Woods Biological Station". Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1596196643385067.

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Kilburn, Vanessa. "Persistence and prevalence of the enzootic chytrid fungus, «Batrachochytrium dendrobatidis», in relation to amphibian population decline in Panama". Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32555.

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The pathogenic chytrid fungus, Batrachochytrium dendrobatidis, causes population decline and extinction of numerous species of tropical, principally montane, amphibians. Is B. dendrobatidis an enzootic pathogen emerging as a disease, or rather a novel invasive pathogen infecting naïve amphibians? Are only high-elevation amphibians susceptible to the pathogen? If the chytrid is enzootic, then it may be in the environment before or after epidemic decline and may infect both montane and lowland amphibians as well as other organisms. To determine distribution of the pathogen and corresponding anuran abundance, I established eight research sites of varying elevations and stages of epidemic infection from west to east, ranging from 45 m to 1215 m elevation throughout Panama west of the Canal. Differential infection susceptibility among anurans was addressed in relation to three ecological factors: anuran body size, season and habitat. Prevalence and infection intensity of the chytrid were determined at all sites and for all factors using sensitive DNA-based RT-qPCR amplification. Amphibian populations at all elevations and stages of decline showed at least some degree of chytrid infection, and the chytrid was found on reptiles. In addition to presence of the pathogen, effects of the disease chytridiomycosis were variably seen at all elevations. Habitat and season did not seem to have a strong effect on infection prevalence and/or intensity, but frogs did appear to show greater infection at smaller anuran body sizes. All of the above results are suggestive of an enzootic pathogen and perhaps only the current epidemic of chytridiomycosis disease is novel. Since the infection
Le champignon pathogène chytrid, Batrachochytrium dendrobatidis, cause la diminution et l'extinction de nombreuses populations d'amphibiens tropicaux, principalement dans les regions à haute altitude. Si le champignon est endémique, il peut rester dans l'environnement après le passage d'une épidémie, contaminant les amphibiens des hautes et basses terres, ainsi que les autres organismes. Les sites de recherche étaient établis à diverses élévations et à différents stades de l'épidémie, à l'ouest du canal de Panama, où l'état des populations d'amphibiens pouvait être examiné. L'hypersensibilité différentielle des grenouilles à la maladie était adressée pour trois facteurs: la taille des grenouilles, la saison et l'habitat. La prévalence et l'intensité de l'infection étaient déterminées pour chaque facteur à tous les sites en utilisant la technique du RT-qPCR. Les amphibiens de toutes les élévations et de tous les stades de l'épidémie ont montré au moins un niveau d'infection, indiquant la présence d'un pathogène endémique. Le chytrid a aussi été trouvé sur les reptiles. En plus de la présense du champignon, les symptômes de la maladie chytridiomycosis ont même été remarqués sur les grenouilles des terres basses. La prévalence de l'infection est restée similaire pour les forêts et les ruisseaux, et aussi pour les deux saisons, et plus élevée pour les petites grenouilles que pour les plus grosses. Puisque l'infection peut rester dans les communautés amphibiennes à toutes altitudes, habitats et saisons, qu'elle peut persister pour longtemps (jusqu'à 11 ans), et qu'elle peut survivre sur d'autres organismes, la réintro

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Blackburn, Laura M. "Status of Blanchard's cricket frogs (Acris crepitans Blanchardi) along their decline front : population parameters, malformation rates, and disease". Virtual Press, 2001. http://liblink.bsu.edu/uhtbin/catkey/1244094.

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The most urgent amphibian conservation issue in the Upper Midwest has been Blanchard's cricket frog (Acris crepitans blanchardi) declines over much of their northern range. Several causes have been proposed to explain these declines, including pesticide applications, disease, habitat loss, and habitat modification. My goal was to explore these proposed causes. Using a combination of field and laboratory analyses, including population analyses, gross inspections for malformations, and a histopathological analysis for indicators of fungus, disease and parasites, I found evidence for disease (a viral infection) and stress (fluctuating asymmetry, malformations and parasitism). Interestingly, the population most affected by these factors was also the one that contained the most animals and was located south of the presumed decline front (i.e., was assumed to be healthy).
Department of Biology

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Goodwin, Cecily Erica Diana. "Hazel Dormouse ecology and conservation in woodlands". Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/32976.

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The extent and quality of forested habitats have changed across Europe and as a result many forest species have suffered declines and range contractions. European legislation has been introduced to conserve those species that have been negatively impacted by widespread land-use changes. In order to assess the needs of declining species and the efficacy of these protective measures, the effects of habitat type, configuration and management on individuals and populations needs to be understood. In this thesis, I have investigated patterns and drivers of variation in the status of populations of hazel dormouse Muscardinus avellanarius in the United Kingdom. I have assessed the effects of variation in habitat on hazel dormice at multiple spatial scales, and related this to woodland management.

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Park, Mi Young. "Modeling Population and Land Use Change within the Metropolitan Areas of Ohio". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1449158006.

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Peters, Ruth. "Risk factors for incident cognitive decline and dementia in a very elderly hypertensive population : a two year prospective cohort study". Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/11863.

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Stan, Amanda B., Thomas B. Maertens, Lori D. Daniels i Stefan Zeglen. "Reconstructing Population Dynamics Of Yellow-Cedar In Declining Stands: Baseline Information From Tree Rings". Tree-Ring Society, 2011. http://hdl.handle.net/10150/622635.

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Yellow-cedar (Chamaecyparis nootkatensis (D. Don) Spach) forests of coastal British Columbia are apparently experiencing decline in a manner similar to that observed in southeastern Alaska. In this pilot study, we collect tree-ring data from live and standing dead yellow-cedar trees from four declining sites on the North Coast of British Columbia. We use this data to compare growth patterns at our sites to those of yellow-cedar trees at non-declining and declining sites in southwestern British Columbia and southeastern Alaska and, in addition, to assess the possibility of reconstructing yellow-cedar population dynamics in declining stands using dendrochronology. We found coherent growth patterns (i.e. marker years and periods of suppression) among yellow-cedar chronologies from non-declining and declining sites across a broad geographic range as well as unique growth patterns between our chronologies from declining sites and those from declining sites in nearby Alaska. Using outer-ring dates of increment cores, we were able to estimate time since death of decade- to century-old standing dead yellow-cedar trees, although the precision of the estimates was influenced by partial cambial mortality and erosion of outer rings. Our results provide baseline dendrochronological information that will be useful for planning future studies that assess growth-climate relations and reconstruct the long-term population dynamics of yellow-cedar in declining stands.

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Webster, Janelle T. "Individual identification, disease monitoring and home range of Leiopelma hamiltoni". Thesis, University of Canterbury. Biological Sciences, 2004. http://hdl.handle.net/10092/1454.

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Amphibian populations are declining on a global scale and although disease outbreaks are a commonly accepted hypothesis they are not the only one. My aims for my thesis were to study the home range of Leiopelma hamiltoni, to determine whether a photographic database could be used to individual identified them and monitor the health status of the population. Habitat loss is a possible cause. For this reason monitoring an animals' home range is a possible method to detect early impacts the population is facing. By tracking 12 L. hamiltoni within a 12 m x 6 m grid on Maud Island, it was shown that the home range size can vary from 0.5 m2 to 25 m2 based on the minimum convex polygon method. However, to track multiple individuals it is important to be able to distinguish among frogs. The commonly used methods of identification, such as toe clipping, pose potentially detrimental effects. Therefore, non-invasive methods based on natural markings need to be established. Through the use of the dark pigmented patterns found on the skin of L. hamiltoni individuals can be identified on recapture with a mean accuracy of 93%. By developing a database to maintain the photographs used for individual identification, the database can also be used to monitor the status of the population. During 2003 numerous L. hamiltoni were observed with denuded patches predominantly on the facial region. By monitoring five individuals within the captive facility at the University of Canterbury it was discovered that frogs appear to be able to cure themselves. Through researching the home range requirements and developing a photographic database to monitor the population status of L. hamiltoni, it will aid in the management of ensuring the long-term survival of this archaic species of frog.

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Fontana, Rodrigo Barbosa. "Atributos ecológicos de anuros neotropicais: o que podem predizer?" reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2018. http://hdl.handle.net/10183/180577.

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O risco de extinção e o declínio populacional de muitas espécies animais na região neotropical estão fortemente relacionados aos processos antrópicos, como a conversão ambiental, mas também aos fatores intrínsecos aos próprios indivíduos, como os atributos. Os anuros correspondem ao grupo vertebrado mais ameaçado atualmente, sofrendo com sérios declínios populacionais. Este trabalho buscou avaliar quais os atributos dos anfíbios neotropicais podem predizer: i) as categorias de ameaça e tendências populacionais destas espécies e ii) a ocorrência de anuros em um ambiente modificado, de matriz agrícola. Para a predição de categorias de ameaça e tendências populacionais utilizamos um banco de dados com atributos de habitat e modos reprodutivos de 3196 espécies de anuros neotropicais. Verificamos que espécies com modos reprodutivos terrestres e desenvolvimento direto tem uma maior tendência a estarem em declínio. Além disso, verificamos que embora os atributos sejam filogeneticamente estruturados, o grau de ameaça parece ser independente de suas histórias evolutivas. Para identificar possíveis relações entre atributos ecológicos e morfológicos de anuros em uma paisagem agrícola no sul do Brasil, registramos a anurofauna com uso de armadilhas de interceptação e queda e procuras ativas em três diferentes distâncias da borda em um ambiente florestal e em uma matriz agrícola. Verificamos que principalmente os atributos ecológicos, como o modo reprodutivo (tanto terrestre como aquático) e o hábito estão relacionados com a ocorrência destas espécies no sistema agrícola, assim como encontramos diferenças entre os atributos morfológicos ao longo do gradiente de distância. Ambos os resultados podem auxiliar na tomada de decisões em planos e projetos de conservação de anuros neotropicais.
The extinction risk and population decline of many animal species in neotropical region are strongly related to anthropic processes, such as environmental conversion, but they are also related to intrinsic factors such as traits. Anurans correspond to the most endangered vertebrate group, suffering serious population declines. This work aimed to evaluate which neotropical anurans traits can predict: i) the categories of threat and population trends of species, and ii) the occurrence of anuran species in modified environments, such as the agricultural matrix. First, we compiled data to 3196 neotropical anuran species. We emphasized the importance of habitat and reproductive modes in threat classifications, as well as verified that species with terrestrial reproductive modes and direct development are more likely to be declining. We also found that although anurans traits being phylogenetically structured, the degree of threat seems to be independent from their evolutionary histories. In addition, to identify possible relation among ecological and morphological anuran traits with agricultural landscape in southern Brazil, we studied the anurofauna using pitfall traps and active searches at three different border distances in a forest environment and in an agricultural matrix. We verified that mostly of the ecological traits, such as the reproductive mode (both terrestrial and aquatic) and the habit, are related to the occurrence of determined species in the agricultural system. And we also found differences among the morphological traits observed through the distance gradient from the border. Therefore, both results present practical importance since it can help herpetologists to making decision about neotropical anurans conservation.

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Gálvez, Nicolás. "The nine lives of a threatened felid in a human-dominated landscape : assessing population decline drivers of the guiña (Leopardus guigna)". Thesis, University of Kent, 2015. https://kar.kent.ac.uk/56643/.

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The world's human population and an expanding agricultural frontier are exerting increasing pressure on the Earth's systems that sustain life resulting in unprecedented levels of biodiversity loss. Carnivores, which play a key role in ecosystem function and integrity, are also particularly threatened by habitat loss and killing by humans in response to livestock predation. At the same time carnivores, particularly felids show a paucity of studies that suggests population assessments and long-term monitoring is an urgent matter. This thesis looks the how habitat loss, fragmentation and human persecution affects predators in an agricultural landscape with particular focus on a species of conservation concern: the small felid guiña (Leopardus guigna) considered vulnerable with a declining population trend. A cost-effective survey framework was developed, which shows existence of trade-offs for researchers and managers to improve population assessments. The drivers of decline of the guiña are assessed with an extensive camera-trap data set showing that the guiña can tolerate a high degree of habitat loss in agricultural land but requires the existence of large farms and high number of forest patches. Retribution killing does not seem to be a significant extinction driver, although there is uncertainty regarding the impact on the population. However, killing behaviour by farmers is predicted by encounters suggesting that poultry management is an effective mitigation measure. Predator specific predictors of killing by farmers were observed but a commonality to all is that knowledge of legal protection does not explain killing suggesting other measures must be taken. Integrating ecological and social knowledge allows us to tease apart the relative importance of different potential extinction pressures effectively and make informed recommendations as to where future conservation efforts should be prioritised.

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Goodrich, Tara Mae. "Long-term Changes in Eelgrass (Zostera marina) Distribution in Taunton Bay, ME: A Quantitative Analysis of Population Decline over the Last Half Century". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/GoodrichTM2006.pdf.

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Sinnott, Tyler King. "Eelgrass (Zostera marina) Population Decline in Morro Bay, CA: A Meta-analysis of Herbicide Application in San Luis Obispo County and Morro Bay Watershed". DigitalCommons@CalPoly, 2020. https://digitalcommons.calpoly.edu/theses/2236.

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The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis Obispo (SLO) County and Morro Bay Watershed by analyzing data of application by mass, area, and intensity to identify herbicides with the highest potential for local environmental pollution. California Pesticide Use Annual Summary Reports (PUASR) from the years 2000 to 2017 were used to obtain data for conducting a meta-analysis to estimate total herbicide application by weight within every township, range, and section for each of the eight selected herbicides: oxyfluorfen, glyphosate, diuron, chlorthal-dimethyl, simazine, napropamide, trifluralin, and oryzalin. A second goal was to select an analytical laboratory that would be best suited for herbicide analysis of estuary sediments to determine the presence, or lack thereof, of the eight selected herbicides. Criteria of consideration in laboratory selection included herbicides detection capabilities, detection/reporting limits, testing prices, chain of custody protocols, turnaround times, and laboratory site locations. The meta-analysis yielded results showing high herbicide application rates in SLO County with glyphosate, oxyfluorfen, and chlorthal-dimethyl being identified as three herbicides of elevated risk for local environmental contamination due high rates of use by mass, by area, and/or intensity during the study timeframe. Additionally, Morro Bay Watershed exhibited moderate rates of herbicide application with chlorthal-dimethyl and glyphosate being of highest risk for contamination and accumulation within the estuary because of high application rates by mass, by area, and/or intensity. Finally, Environmental Micro Analysis (EMA) and Primus Group, Inc. (PrimusLabs) were identified as the top candidates for analytical laboratory testing of Morro Bay Estuary sediment samples to be obtained and tested for the selected herbicides. These laboratories provide superior analytical capabilities of the eight herbicides, impressive reporting limits or lower detection limits, competitive testing prices for detecting multiple constituents in multiple samples, robust chain of custody protocols, options for quick turnaround times, and laboratory site locations within California.

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Willingham, Alison N. "Emerging Factors Associated With The Decline Of A Gray Fox Population And Multi-Scale Land Cover Associations Of Mesopredators In The Chicago Metropolitan Area". The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1228336802.

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Van, der Westhuizen Rickert. "Biology and management affecting the decline of a black rhinoceros, Diceros bicornis minor (Linnaeus, 1758), population in Ndumo Game Reserve, KwaZulu-Natal, South Africa". Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/31147.

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Black rhinoceros (Diceros bicornis) are classified as critically endangered on the IUCN red data list (IUCN 2010). In Ndumo Game Reserve in northern KwaZulu-Natal, South Africa, a black rhino population has seen a decline in numbers from nearly 50 rhino in 1988 to only eight in 2006. This study aimed to determine the factors or events responsible for the decline in black rhino numbers in Ndumo. The first part of this study focuses on the historical data and literature on Ndumo’s black rhino population. Specifically, I examined historical data regarding Ndumo’s black rhino population estimates, recruitment patterns, mortality rates, number of removals, introductions, densities and other large herbivore population estimates. Results suggest that a combination of high removals due to inaccurate estimates and competition from other herbivore populations, specifically nyala (Nyala angasi) and impala (Aepyceros melampus), played a role in this population’s decline. Also, a change in the Usuthu River course negatively affected the population’s social structure, movement patterns and recruitment success. The introduction of five black rhino from Hluhluwe-iMfolozi Park in 2008 seems to have been a success, and should increase reproductive success. Secondly, we determined the amount of browse currently (2008) available to black rhino in Ndumo, the proportional species composition of this browse and its suitability for black rhino. The results show that browse availability is fairly high (average of 17.8%) in Ndumo but the suitability is low. Croton menyhartii is the single biggest contributor to browse availability in Ndumo, contributing 25% of all available browse. This plant species is unfortunately rejected by black rhino and most other browsers. Furthermore, two invasive alien plant species (Chromolaena odorata and Lantana camara) are amongst the four most abundant plant species in Ndumo and are also rejected by black rhino. An effective alien plant clearing programme is needed to eradicate invasive alien species in Ndumo, which will help alleviate the poor browse conditions. A population viability analysis (PVA) was done during the last part of the study to predict the possibility of extinction or survival of this black rhino population in future. The VORTEX model was used in this study. Data and trends as actually observed in Ndumo since 1988 was used as the first simulation’s input parameters, to test whether the model will predict a similar decline in black rhino numbers as observed in Ndumo. Furthermore, sensitivity analyses with different input parameters were done to test the probability of extinction or survival under all possible circumstances. The model predicted a high probability of survival, even with most of the sensitivity analyses, suggesting that small populations of less than 50 individuals are viable if managed correctly. Parameters that impacted negatively on the growth rate of this population were density dependant breeding, a low recruitment rate and a decline in carrying capacity.
Dissertation (MSc)--University of Pretoria, 2012.
Centre for Wildlife Management
MSc
Unrestricted

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Botero, Gomez Adriana. "Genotypic and phenotypic diversity of trypanosomes infecting Australian marsupials and their association with the population decline of the brush-tailed bettong or woylie (Bettongia penicillata)". Thesis, Botero Gomez, Adriana (2014) Genotypic and phenotypic diversity of trypanosomes infecting Australian marsupials and their association with the population decline of the brush-tailed bettong or woylie (Bettongia penicillata). PhD thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/24863/.

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Trypanosomes are flagellated blood parasites that are capable of infecting virtually all classes of vertebrates. They range from non-pathogenic species to those that are highly pathogenic and are the causative agents of many diseases of medical and veterinary importance. While much is known of their impact on human health or economic development, a great deal less is known of those associated with wildlife. Within Australia, trypanosomes have been found naturally infecting a wide range of native marsupials, most of which are considered threatened or endangered. However, their research has largely been confined to the description of trypanosome morphology in blood, and a complete lack of information regarding their life cycle, virulence, and pathogenicity is evident. This study therefore, aimed to investigate the genotypic and phenotypic diversity of Trypanosoma spp. infecting Western Australia marsupials and to determine their potential pathogenicity with particular emphasis in the critically endangered marsupial, the woylie (Bettongia penicillata). The genotypic characterisation was achieved using a combination of sequencing and phylogenetic analysis of trypanosomes in the blood and tissues of nine different marsupial species, as well as the sequencing of partial fragments of the minicircles of the kinetoplast DNA of trypanosomes isolated in culture. The phenotypic characterisation involved a combination of histology, microscopy techniques, and in vitro experiments of cell infection and drug susceptibility. Results revealed that eight different genotypes belonging to three different Trypanosoma species: T. copemani, T. vegrandis, and T. sp H25 were found infecting woylies (Bettongia penicillata), quendas (Isoodon obesulus), quokkas (Setonix brachyurus), tammar wallabies (Macropus eugenii), banded hare wallabies (Lagostrophus fasciatus), boodies (Bettongia lesueur), Chuditches (Dasyurus geoffroii), common brush tailed possums (Trichosurus vulpecula), and western grey kangaroos (Macropus fuliginosus). However, the woylie was the only marsupial species where single individuals and single tissues were co-infected with genotypes belonging to the three different Trypanosoma species. Furthermore, T. copemani G2, the predominant trypanosome in the declining population of woylies, was shown to be able to infect tissue cells and generate a strong immune response characterised by tissue degeneration and necrosis in vital organs, suggesting an association between these infections and the decline of the woylie. Comparative analysis between T. copemani G2 and the pathogenic T. cruzi showed not only similarities in their capacity to infect tissue cells, but also in drug susceptibility and kinetoplast DNA organisation. In summary, this study not only contributes valuable information towards directing management decisions for endangered species where trypanosomes are known to be present at high prevalence levels, but also provides new knowledge about the evolutionary biology and relationships that Australian trypanosomes have with the exotic and pathogenic T. cruzi.

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Rannikko, I. (Irina). "Change in cognitive performance and its predictors in general population and schizophrenia in early midlife:the Northern Finland Birth Cohort 1966 Study". Doctoral thesis, Oulun yliopisto, 2016. http://urn.fi/urn:isbn:9789526211947.

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Abstract The aim of this study was to provide novel information on the change of cognitive performance and its predictors in early midlife between ages of 34 and 43 years. The change in verbal episodic memory between non-psychotic and schizophrenia samples was compared in the Northern Finland Birth Cohort 1966. In the non-psychotic sample, associations between primary school performance, sociodemographic factors and body mass index (BMI), and in the schizophrenia sample, between premorbid school performance and severity of illness with the change in cognitive performance were evaluated. There was no evidence of greater decline in verbal episodic memory in the schizophrenia sample, compared to the non-psychotic sample, though the schizophrenia sample had an overall lower cognitive performance at the baseline. In the non-psychotic sample, male gender, poorer school performance, increases in BMI and having no children predicted a decline in verbal episodic memory; poorer school performance and low vocational education and occupational class predicted a decline in visual episodic memory; and having children predicted a decline in executive function. In the schizophrenia sample, poorer premorbid school performance, but not the later course of illness, was related to a decline in cognitive performance. This study is one of the few studies to investigate the predictors of change in cognitive performance in the early middle-aged general population, and the first to investigate the predictors of cognitive change in early midlife schizophrenia. To summarize; poor cognitive performance in adolescence may be considered as a vulnerability marker for a later impairment in cognitive functioning. In schizophrenia, cognitive ability possibly declines mostly in a normative fashion with aging at the same rate as in the general population rather than as a result of neurodegenerative processes. These results might improve our understanding of midlife change in cognitive functioning and may also help to develop effective interventions of cognitive impairment in schizophrenia
Tiivistelmä Tutkimuksen tavoitteena oli tuoda uutta tietoa kognitiivisen suoriutumisen muutoksesta sekä siihen liittyvistä tekijöistä varhaisessa keski-iässä ikävuosien 34 ja 43 välillä. Tutkimuksessa verrattiin kielellisessä muistisuoriutumisessa tapahtuvaa muutosta yleisväestön ja skitsofrenia-aineiston välillä Pohjois-Suomen vuoden 1966 syntymäkohortissa. Lisäksi yleisväestössä tutkittiin koulumenestyksen, sosiodemografisten tekijöiden ja painoindeksin yhteyttä ja skitsofrenia-aineistossa koulumenestyksen ja sairauden varhaisen kulun yhteyttä kognitiivisen suoriutumisen muutokseen. Kielellisen muistisuoriutumisen heikentyminen ei ollut skitsofrenia-aineistossa suurempaa verrattuna yleisväestöön, joskin kognitiivisen suoriutumisen lähtötaso oli skitsofrenia-aineistossa alempi. Yleisväestössä miessukupuoli, heikompi koulumenestys peruskoulussa, painoindeksin nousu ja lapsettomuus olivat yhteydessä kielellisen muistisuoriutumisen heikkenemiseen, heikompi koulumenestys peruskoulussa ja matala ammatillinen koulutus ja sosioekonominen asema näönvaraisen muistisuoriutumisen heikkenemiseen ja vanhemmuus toiminnanohjauksellisten taitojen laskuun. Skitsofrenia-aineistossa heikompi menestys peruskoulussa ennusti kognitiivisen suoriutumisen heikkenemistä kielellisen ja näönvaraisen muistin sekä toiminnanohjauksellisten taitojen osa-alueilla. Oireiden vakavuus ja toimintakyky sairastumisen jälkeen eivät liittyneet kognitiivisen suoriutumisen muutokseen. Tämä on yksi harvoista tutkimuksista, joissa on selvitetty kognitiivisen suoriutumisen muutosta ennustavia tekijöitä varhaisessa keski-iässä yleisväestössä, ja ensimmäinen, jossa on tutkittu kognitiivisen suoriutumisen muutosta ennustavia tekijöitä skitsofrenia-aineistossa varhaisessa keski-iässä. Yhteenvetona voidaan todeta, että heikko nuoruusiän koulumenestys voi ennustaa kognitiivisen suoriutumisen heikkenemistä varhaisessa keski-iässä. Kognitiivinen suorituskyky näyttää heikkenevän skitsofreniassa enemmänkin tavanomaisella tavalla ikääntymisen myötä kuin neurodegeneratiivisen prosessin seurauksena. Tämän tutkimuksen tulokset tuovat uutta tietoa kognitiivisen suoriutumisen muutoksesta keski-ikäisessä väestössä. Tuloksia voidaan myös hyödyntää kehitettäessä kognitiivisten häiriöiden hoitoa skitsofreniassa

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