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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Capture-Recapture Methodology to Study Rare Conditions Using Surveillance Data for Fragile X Syndrome and Muscular Dystrophy

Smith, Michael G., Royer, Julie, Mann, Joshua, McDermott, Suzanne, Valdez, Rodolfo 21 April 2017 (has links)
Rare conditions can be catastrophic for families and the implications for public health can be substantial. Our study compared basic surveillance through active medical record review with a linked administrative data file to assess the number of cases of two rare conditions, fragile X syndrome (FXS) and muscular dystrophy (MD) in a population. Methods: Two methods of data collection were used to collect information from five counties comprising two standard metropolitan statistical areas of South Carolina. The passive system relied mostly on health claims data using ICD-9 CM diagnostic codes. The active system relied on a nurse abstracting records from a list of all licensed physicians with specialties in neurology, orthopedics, and genetics. Results: There were 141 FXS cases and 348 MD cases that met the case definitions using active surveillance. Additional cases were found for both conditions but they were determined to not be true cases. After linking the actively collected MD and FXS cases to passive datasets, we found that the estimated total numbers of cases were similar to using capture-recapture analysis; the positive predictive values for cases identified in the passive system were 56.6% for MD and 75.7% for FXS. Conclusions: Applying capture-recapture methods to passively collected surveillance data for rare health conditions produced an estimate of the number of true cases that was similar to that obtained through active data collection.
32

Assessing the Influence of Prescribed Fire on Faunal Communities in a Pyric Landscape

Jorge, Marcelo Haidar 31 January 2020 (has links)
Understanding the link between environmental factors such as disturbance events, land cover, and soil productivity to spatial variation in animal distributions and vital rates is fundamental to population ecology and wildlife management. The Longleaf pine (Pinus palustris; hereafter, LLP) ecosystem is an archetypal fire-mediated ecosystem, which has seen drastic reductions in land area due to fire suppression. Current restoration utilizes prescribed fire and hardwood removal, but more research is needed to understand the influence of these restoration efforts on the wildlife that exist in that ecosystem. As such, we conducted field surveys on Camp Blanding Joint Training Center and Wildlife Management Area to understand how fire influences relative abundances of mammalian predators, occupancy and species richness of avian species, guilds and communities, and vital rates of white-tailed deer (Odocoileus viginianus) fawns. Our results indicated that mammalian predator space use, and avian species richness were influenced by fire and land cover. Mammalian predator space use was altered by fire conditions and land cover. This mechanism may support predator management strategies that utilizes commonly management techniques for the restoration and conservation of the LLP ecosystem to indirectly alter predator distributions, which has the potential to positively affect the management of important species within this ecosystem. Some mammalian mesocarnivores historically common throughout the southeastern United States were rarely detected, suggesting more research is needed to identify the cause of the potential decline in mesocarnivores in the Southeastern United States. Avian species richness at the community level was positively influenced by the heterogeneity of post fire conditions, or pyrodiversity. Avian species richness of the cavity nesting guild was negatively influenced by increasing time-since-fire. Our results suggest that managers can promote avian community diversity by reducing the size of burn units to create areas with multiple adjacent burn units, with unique fire histories and a mosaic of post-fire conditions. Lastly, fawn recruitment was greater on the higher productivity site than the low productivity site on CB. However, within sites soil productivity did not have a demonstrable effect. In fact, we observed differences between sites, but did not observe any effects of covariates on spatial variation in density or survival of fawns within sites. Although we did not explicitly test the factors influencing our parameters between sites, we hypothesize that the variation in coyote activity rates as well as soil productivity and its subsequent effects (i.e. forage availability, concealment cover, and land cover type) likely drove the differences we saw between sites. These results are relevant to local managers and provide support for unit-specific, deer management on CB. In conclusion, understanding the influence of fire in a frequently burned landscape allows us to better inform management of predators and avian communities using prescribed burns, and the differences in deer populations between areas allowed us to better in inform managers on harvest quotas so that the magnitude of the effect of harvest can better match the population vital rates of each area. / Master of Science / Understanding the link between environmental factors such as fire, land cover and soil productivity is essential for wildlife managers to maintain healthy wildlife populations. The Longleaf pine (Pinus palustris) ecosystem requires frequent fire and has seen drastic reductions in land area due to fire suppression. Current restoration utilizes prescribed fire, controlled burning of an area, and hardwood removal, logging hardwood trees such as oaks, but more research is needed to understand how this restoration influences the wildlife in the longleaf pine ecosystem. As such, we collected data collected from Camp Blanding Joint Training Center and Wildlife Management Area to understand how fire influences the relative numbers of mammalian predators, the distribution and species richness (i.e. number of unique species) of avian species, guilds and communities, and vital rates (i.e. births, survival to a certain age) of white-tailed deer fawns. Our results indicated that mammalian predator distributions, and avian species richness were influenced by fire and land cover. Mammalian predator space use was altered by fire conditions and landcover, which supports a predator management strategy that utilizes prescribed burning and hardwood removal used in restoration and conservation of the LLP ecosystem to indirectly alter predator distributions. Some mammalian mesocarnivores (i.e. foxes, skunks, weasels, etc.) historically common throughout the southeastern United States were rarely detected, suggesting more research is needed to identify the cause of the potential decline of cryptic mesocarnivores in the Southeastern United States. Avian species richness, number of unique species, at the community level was positively influenced by pyrodiversity, the number of unique burn years in an area. This supports and further extends the 'pyrodiversity begets biodiversity' hypothesis for avian species, which states that greater pyrodiversity increases the diversity of bird species in that area. Avian species richness of cavity nesting birds decreased with increasing time since fire. Our results suggest that managers can promote avian community diversity by reducing the size of burn units to create areas with multiple adjacent burn units, with unique fire histories and a mosaic of post-fire conditions. Lastly, fawn recruitment was greater on the higher productivity site than the low productivity site, however, within sites soil productivity did not seem to influence birth and recruitment. Although we did not statistically test the factors influencing our parameters between sites, we hypothesize that the variation in coyote activity rates as well as soil productivity and its subsequent effects (i.e. forage availability, concealment cover, and land cover type) likely drove the differences we saw between sites. These results are relevant to local managers and provide support for managing deer differently across both sites. In conclusion, understanding the influence of fire in a frequently burned landscape allows us to better inform management of predators and avian communities using prescribed burns, and the differences in deer populations between areas allowed us to better in inform managers on harvest quotas so that the magnitude of the effect of harvest can better match the population vital rates of each area.
33

Estimating abundance of rare, small mammals : a case study of the Key Largo woodrat (Neotoma floridana smalli)

Potts, Joanne M. January 2011 (has links)
Estimates of animal abundance or density are fundamental quantities in ecology and conservation, but for many species such as rare, small mammals, obtaining robust estimates is problematic. In this thesis, I combine elements of two standard abundance estimation methods, capture-recapture and distance sampling, to develop a method called trapping point transects (TPT). In TPT, a "detection function", g(r) (i.e. the probability of capturing an animal, given it is r m from a trap when the trap is set) is estimated using a subset of animals whose locations are known prior to traps being set. Generalised linear models are used to estimate the detection function, and the model can be extended to include random effects to allow for heterogeneity in capture probabilities. Standard point transect methods are modified to estimate abundance. Two abundance estimators are available. The first estimator is based on the reciprocal of the expected probability of detecting an animal, ^P, where the expectation is over r; whereas the second estimator is the expectation of the reciprocal of ^P. Performance of the TPT method under various sampling efforts and underlying true detection probabilities of individuals in the population was investigated in a simulation study. When underlying probability of detection was high (g(0) = 0:88) and between-individual variation was small, survey effort could be surprisingly low (c. 510 trap nights) to yield low bias (c. 4%) in the two estimators; but under certain situations, the second estimator can be extremely biased. Uncertainty and relative bias in population estimates increased with decreasing detectability and increasing between-individual variation. Abundance of the Key Largo woodrat (Neotoma floridana smalli), an endangered rodent with a restricted geographic range, was estimated using TPT. The TPT method compared well to other viable methods (capture-recapture and spatially-explicit capture-recapture), in terms of both field practicality and cost. The TPT method may generally be useful in estimating animal abundance in trapping studies and variants of the TPT method are presented.
34

L’illusion des signaux pénaux : l’effet tendancieux de l’impunité différentielle

Charette, Yanick 03 1900 (has links)
Réalisé sous la co-direction de Pierre Tremblay / En utilisant une approche économique du crime, cette thèse s’intéresse à la capacité des délinquants à minimiser leurs risques d’arrestation ou de condamnation et à l’impact de cette adaptation différentielle sur la manière dont on devrait interpréter le profil du délinquant qu’offrent les statistiques policières ou correctionnelles. Les études qui ont utilisé cette approche ont surtout insisté sur les coûts pénaux, mais omettent de prendre en considération les bénéfices que procurent les crimes aux délinquants et leur vulnérabilité différentielle aux risques, pourtant essentiels à la validation de cette approche. En considérant les expériences pénales comme un signal d’information entre les délinquants et les acteurs du système de justice criminelle, ceux-ci devront interpréter ce signal avec du bruit : l’évitement pénal. Cette distorsion du signal induit chez les policiers, les juges ou les agents correctionnels l’image trompeuse du délinquant inefficace. Notre première analyse, basée sur une méthode d’estimation des populations, évalue l’intensité de cette distorsion à travers les différentes étapes du système pénal (arrestation, condamnation, incarcération). Ce bruit ne se distribue pas de façon aléatoire, mais est influencé par les caractéristiques des délinquants. Les délinquants les moins vulnérables à la détection se révèlent plus expérimentés dans la réalisation de leurs délits : plus âgés, plus mobiles, plus spécialisés. Notre deuxième analyse s’est intéressée à l’effet de l’évitement pénal sur notre interprétation de la récidive. Les données de délinquance autorévélée d’un échantillon de détenus, mises en parallèle avec les données pénales, ont permis d’estimer la capacité individuelle d’évitement pénal. Lorsqu’on prend en considération cette disposition, les antécédents pénaux deviennent un indicateur des échecs auxquels les délinquants font face durant leur trajectoire délinquante plutôt que de la poursuite même de cette trajectoire, créant l’illusion de l’efficacité de sa prédiction par les antécédents pénaux. L’intensité des coûts pénaux antérieurs réduit la probabilité de la poursuite de la carrière. Les bénéfices soutirés des activités criminelles augmentent cette probabilité, alors que les opportunités d’emplois conventionnels la réduisent. Notre troisième analyse reprend une stratégie d’estimation des populations qui combine une variante adaptée aux déplacements urbains des délinquants et procure une perspective plus macrosociologique à nos observations des chapitres précédents parce qu’elle étudie l’évolution des populations délinquantes de différents groupes ethniques en fonction de la surveillance policière à laquelle ils font face. Nos résultats indiquent que, pour les délits dont le signalement est principalement proactif, un surplus de surveillance d’un groupe induit une baisse de surveillance auprès des autres groupes. Il en résulte que l’effet préventif obtenu dans le premier cas est annulé par un effet incitatif dans le second cas, celui-ci étant suffisant pour observer une augmentation générale de la population délinquante. Cet effet Harcourt vient corriger l’illusion de l’efficacité du profilage criminel ou des interventions policières ciblées. En conclusion, on constate qu’en se basant seulement sur des données pénales, on entretient l’illusion de l’efficacité pénale. Le bruit causé par l’évitement pénal ou l’impunité différentielle des délinquants a des répercussions importantes sur notre compréhension du comportement adaptatif des délinquants. / Using an economic approach to crime, this thesis focuses on offenders’ ability to minimize their risks of arrest or conviction and on the effect of this differential adaptation on the way we should interpret offenders’ profile based on police and correctional statistics. Studies using the approach mostly insisted on penal costs, but overlooked the benefits that offenders gain from crime and their differential vulnerability to risks, essential to its interpretation. Considering penal experiences as an information signal between offenders and criminal justice system officials, both parties would need to interpret this signal with a serious amount of noise: penal avoidance. This signal distortion induced to police officers, judge or correctional officers a misleading depiction of inefficient offenders. Our first analysis, based on a population estimates method, assess the intensity of this distortion through the different steps of the penal system (arrest, conviction, incarceration). This noise is not randomly distributed, but influenced by offenders’ characteristics. Offenders who are less prone to detection are be more experienced in the achievement of their offences: older, more geographically mobile, more specialized. Our second analysis looked at the effect of penal avoidance on our interpretation of recidivism. Self-reported offending data from an inmate sample, in conjunction with penal data, allowed us to assess individual penal avoidance ability. When taking into consideration penal avoidance, past penal experiences appear to be an indicator of failure faced by offenders during their criminal career rather than its true continuation, creating the illusion of the efficient prediction of recidivism using past penal experiences. The intensity of past penal costs reduces the probability of the continuation of the criminal career. The benefits of crime increase this probability while legitimate opportunities reduce it. Our third analysis, also using a population estimates methods combined to a variation adapted for offenders’ urban mobility, gives a macro perspective to our past observations and allowed us to examine the evolution of offenders populations from different ethnic groups in function of the intensity of police surveillance they each are subject to. Our results suggest that, for offenses with more proactive reporting, an increased surveillance of one group results in the decreased surveillance of other groups. The preventive effect on the first group is then cancelled by an incentive effect on the second. This effect alone suffices to increase the total criminal population. This Harcourt effect corrects the illusion of criminal profiling or targeted strategies efficiency. In conclusion, we observe that relying solely on penal data to assess offenders behaviours maintain an illusion of penal efficiency. The noise caused by offenders’ penal avoidance or differential impunity influences our understanding of offenders’ adaptive behaviors.
35

Démographie et réponses adaptatives des populations végétales aux changements environnementaux / Demography and adaptive responses of plant populations to environmental changes

Hadjou Belaid, Asma 13 November 2018 (has links)
La région méditerranéenne, hot-spot de biodiversité avec un fort taux d'endémisme, est classée parmi les zones les plus touchées par le changement climatique. La conservation des espèces nécessite de comprendre finement leur démographie face à ces changements, mais aussi leur capacité à s’adapter à ces nouvelles conditions. Au cours de cette thèse, deux espèces végétales rares méditerranéennes ont été étudiées, Centaurea corymbosa et Brassica insularis, en utilisant des modèles mathématiques récents pour analyser des suivis démographiques de long-terme (22 ans et 18 ans). Dans la première partie de cette thèse, des modèles de projection matriciels ont été construits afin d’analyser la variation spatio-temporelle des taux d’accroissement des populations de C. corymbosa. Cela a permis d'identifier les facteurs climatiques clefs qui impactent les taux d’accroissement des populations, et plus finement, les paramètres de survie, de floraison et de fécondité. Une analyse de viabilité des populations a été réalisée sous différents scénarios climatiques. Dans un second temps, une analyse de la capacité des populations de C. corymbosa à répondre à ces changements climatiques a été effectuée avec un modèle de projection intégral. Les changements des traits d’histoire de vie au cours du temps ont montré que la stratégie de floraison observée répond aux variations climatiques en suivant la même direction que la stratégie optimale. Ceci montre que les populations sont capables de s’adapter au changement climatique. Enfin, des modèles de capture-recapture (CR) ont été construits afin de déterminer l’influence de la faible détectabilité des individus sur l’estimation des paramètres démographiques chez B. insularis. Les probabilités de survie estimées par l’approche classique sont inférieures à celles estimées par les modèles CR. Les paramètres estimés par les deux approches sont en général très corrélés, à l'exception d'une population montrant des problèmes d'identification des individus. L'ensemble de cette thèse est replacé dans le cadre de la biologie de la conservation des espèces végétales, notamment en suggérant de prendre en compte leur capacité de réponse au changement climatique. / Mediterranean region is a biodiversity hot-spot with a high endemism rate and is classified among the areas most sensitive to climate change. Deep understanding of demography and evolution following these changes is a necessity for species conservation. During this thesis, two rare Mediterranean plant species have been studied, Centaurea corymbosa and Brassica insularis, using recent mathematical models to analyse long term demographic datasets (22 and 18 years). In the first part of this thesis, matrix projection models have been used to analyse spatio-temporal variation in population growth rate in C. corymbosa. Major climatic parameters that impact population growth rate and survival, flowering and fecundity have been identified. A population viability analysis has been performed under various climatic scenarios. In a second part, an analysis of the population ability of C. corymbosa to response to these climatic changes has been performed using integral projection models. Temporal variation of life-history traits showed that the realized flowering strategy varied with climatic conditions following the same direction than the optimal flowering strategy. It can thus be concluded that the studied populations can adapt to climatic changes. Finally, capture-recapture models have been applied on the Brassica insularis dataset to analyse the effect of plant detectability on demographic parameter estimations. Survival probabilities obtained with the classical approach are lower than the ones estimated using the CR models. However, the parameters estimated using both methods are highly correlated, except for one population where individual identification is problematic. Results of this thesis are linked to some considerations in conservation biology of plants, particularly in link to their ability to respond to climatic changes.
36

Estimativa da prevalência da Hepatite C, no município de São Paulo, 2003 a 2008, usando o método de captura-recaptura / Estimated prevalence of hepatitis C in the city of São Paulo, 2003 a 2008, using the capture-recapture method

Koizumi, Inês Kazue 03 September 2010 (has links)
RESUMO Introdução - Estima-se que 2 por cento da população mundial esteja infectada pelo Vírus da Hepatite C e assim, a hepatite C é considerada importante problema de saúde pública por sua magnitude e gravidade. O uso de bancos de dados, originados pelos serviços de saúde, pode ser uma alternativa aos tradicionais inquéritos epidemiológicos de base populacional. Conjugar o desenvolvimento na área dos sistemas de informação com a necessidade de avançar no conhecimento das doenças importantes para a saúde pública é o desafio que se coloca no cenário da pesquisa epidemiológica. Objetivos - Estimar a subnotificação e a prevalência da hepatite C, no município de São Paulo, no período de 2003 a 2008, usando o método de captura-recaptura e descrever o perfil dos casos registrados em quatro Sistemas de Informação em Saúde. Método - Estudo transversal usando dados secundários registrados no Sistema de Informação de Agravos de Notificação (SINAN), no Sistema de Informação de Mortalidade (SIM), no Sistema de Informação Hospitalar (SIH) e no Sistema de Comunicação Hospitalar (CIH), empregando o método de captura e recaptura. Os bancos SIH e CIH foram unificados para o cálculo da estimativa de casos de hepatite C usando o método de capturarecaptura com a aplicação do modelo log-linear. Resultados O SINAN permitiu detectar características importantes dos portadores da hepatite C, como o uso de drogas injetáveis e inaláveis, a co-infecção com o VHB e com o HIV. A subnotificação estimada de casos de hepatite C no SINAN, em relação ao SIH, SIM e CIH, separadamente, foi de 60,3 por cento (IC95 por cento: 58,3 por cento;62,1 por cento), 73,7 por cento (IC95 por cento: 71,9;75,3 por cento) e 83,1 por cento (IC95 por cento: 66,9 por cento;84,9 por cento), respectivamente. O número estimado de casos de hepatite C utilizando três fontes de dados e com a aplicação do modelo log-linear foi de 56.935 (IC95 por cento por cento: 53.154;61.192).Com este resultado estimou-se a subnotificação de 75,5 por cento (IC95 por cento: 73,7 por cento;77,2) e a prevalência da hepatite C de 0,5 por cento (IC95 por cento: 0,50;0,57 por cento). Conclusões A elevada subnotificação encontrada deve desencadear medidas que tornem o Sistema de Vigilância Epidemiológica da hepatite C mais ativo na captação de casos da doença. O método de captura-recaptura é útil para a prática dos serviços de vigilância epidemiológica e a prevalência encontrada neste estudo refere-se aos casos mais graves de hepatite C / Summary Introduction It has been estimated that 2 per cent of the worlds population are infected with Hepatitis C Virus and, thus, hepatitis C is considered a major public health problem due to its magnitude and severity. The use of datasets, originated from health services, can be an alternative to traditional population-based surveys. Combining information systems development with the need of enhanced knowledge of diseases of public health importance is the challenge that is put forward in the epidemiological research scenario. Objectives To estimate the under-reporting and the prevalence of hepatitis C, in the city of São Paulo, in the period 2003 to 2008, using the capture-recapture method and to describe the cases recorded in four Health Information Systems. Method Cross-sectional study using secondary data from: the Information System for Notifiable Diseases (ISND), the Mortality Information System (MIS), the Hospital Information System (HIS), and from the Hospital Communication Information System (HCIS) employing the capture-recapture method. The HIS and HCIS datasets were merged together to estimate the total number of hepatitis C cases using the capture-recapture method with log-linear modeling. Results The ISND dataset allowed detecting important characteristics of the hepatitis C carriers, as the use of injecting and inhaled drugs and the co-infection with the HBV and HIV. The estimated under-reporting of hepatitis C cases in the ISND, when comparing with the HIS, MIS and CHIS, separately, was 60.3 per cent (CI95 per cent: 58.3 per cent;62.1 per cent), 73.7 per cent (CI95 per cent: 71.9;75.3 per cent) e 83.1 per cent (CI95 per cent: 66.9 per cent;84.9 per cent), respectively. The estimated number of hepatitis C cases using three data sources and log-linear modeling was 56,935 (CI95 per cent: 53,154;61,192). With this result it was estimated an under-reporting of 75.5 per cent (CI95 per cent: 73.7 per cent;77.2 per cent) and a prevalence of hepatitis C of 0.53 per cent (CI95 per cent: 0.50 per cent;0.57 per cent). Conclusions The elevated underreporting found must lead to measures that make the Epidemiologic Surveillance System of hepatitis C more active in the capture of cases of the disease. The capture-recapture method is useful for the practice of epidemiological surveillance services and the prevalence found in this study refers to the severer cases of hepatitis C
37

Parâmetros populacionais do boto-cinza, Sotalia guianensis (Cetartiodactyla: Delphinidae), no estuário de Cananéia entre 2015 e 2016 / Population parameters of Guiana dolphin, Sotalia guianensis (Cetartiodactyla: Delphinidae), in the Cananeia estuary between 2015 and 2016

Mello, Aline Boutros de 02 September 2016 (has links)
Estimativas robustas de parâmetros populacionais de cetáceos são necessárias para a criação de estratégias de manejo e de conservação eficazes. Dentre os métodos comumente utilizados para estimar parâmetros demográficos, o método de captura e recaptura tem se destacado devido às suas vantagens e precisão. O objetivo deste estudo foi estimar parâmetros populacionais do boto-cinza, Sotalia guianensis, no estuário de Cananéia (25° 03\' S; 47° 55\' W), mediante o uso de modelos de captura-recaptura. O delineamento robusto de Pollock foi utilizado para estimar abundância, sobrevivência, emigração temporária e probabilidades de captura. Levantamentos de fotoidentificação sistemáticos foram conduzidos em três temporadas entre janeiro de 2015 e fevereiro de 2016. O modelo que melhor representou os dados mostrou uma população com sobrevivência constante, emigração temporária aleatória e probabilidades de captura com heterogeneidade variando no tempo e entre as estações. Foram estimados 430 (95% CI: 410-451) indivíduos no verão/2015; 384 (95% CI: 366-403) indivíduos no inverno/2015; e 414 (95% CI: 392-438) indivíduos no verão de 2016. A taxa de emigração temporária (γ\'\'=γ\') foi de 0,05 (± 0,03) e a estimativa de sobrevivência aparente foi de 0,86 (± 0,06). As probabilidades de captura variaram entre as temporadas e os períodos secundários, com valores médios de 0,24 (± 0,02) no verão de 2015; 0,34 (± 0,03) no inverno de 2015; e 0,24 (± 0,03) no verão de 2016. Esses resultados sugerem que as variáveis ambientais entre as estações do ano têm pouco efeito sobre o tamanho da população local, a qual se encontra em equilíbrio e utiliza uma área ainda protegida de ameaças à sua perpetuação. / Reliable estimates of cetacean population parameters are necessary for effective management and conservation strategies. Capture-recapture methods have been commonly used to estimate demographic parameters because of their advantages and accuracy under a set of assumptions. The aim of this study was to estimate population parameters of Guiana dolphins, Sotalia guianensis, in the Cananeia estuary (25°03\' S; 47°55\' W) using capture-recapture models. The Pollock\'s robust design was used to estimate abundance, survival, temporary emigration and capture probabilities. Systematic boat-based photo-identification surveys were conducted in three seasons between Jan/2015 and Feb/2016. The best fitting model showed a population with constant survival, random temporary emigration and heterogeneous time-varying capture probabilities. Population sizes were of 430 (95% CI: 410-451) individuals in summer of 2015, 384 (95% CI: 366-403) individuals in winter of 2015 and 414 (95% CI: 392-438) individuals in summer of 2016. Temporary emigration rate (γ\'\'=γ\') was 0.05 (± 0.03) and apparent survival estimate was 0.86 (± 0.06). Capture probabilities varied greatly among seasons and secondary periods with mean values of 0.24 (± SE 0.02) in summer of 2015, 0.34 (± SE 0.03) in winter of 2015 and 0.24 (± SE 0.03) in summer of 2016. These results suggest that environmental variables between seasons have little effect on the size of the local population, which is stable and uses an area that is still protected from threats.
38

Parâmetros populacionais do boto-cinza, Sotalia guianensis (Cetartiodactyla: Delphinidae), no estuário de Cananéia entre 2015 e 2016 / Population parameters of Guiana dolphin, Sotalia guianensis (Cetartiodactyla: Delphinidae), in the Cananeia estuary between 2015 and 2016

Aline Boutros de Mello 02 September 2016 (has links)
Estimativas robustas de parâmetros populacionais de cetáceos são necessárias para a criação de estratégias de manejo e de conservação eficazes. Dentre os métodos comumente utilizados para estimar parâmetros demográficos, o método de captura e recaptura tem se destacado devido às suas vantagens e precisão. O objetivo deste estudo foi estimar parâmetros populacionais do boto-cinza, Sotalia guianensis, no estuário de Cananéia (25° 03\' S; 47° 55\' W), mediante o uso de modelos de captura-recaptura. O delineamento robusto de Pollock foi utilizado para estimar abundância, sobrevivência, emigração temporária e probabilidades de captura. Levantamentos de fotoidentificação sistemáticos foram conduzidos em três temporadas entre janeiro de 2015 e fevereiro de 2016. O modelo que melhor representou os dados mostrou uma população com sobrevivência constante, emigração temporária aleatória e probabilidades de captura com heterogeneidade variando no tempo e entre as estações. Foram estimados 430 (95% CI: 410-451) indivíduos no verão/2015; 384 (95% CI: 366-403) indivíduos no inverno/2015; e 414 (95% CI: 392-438) indivíduos no verão de 2016. A taxa de emigração temporária (γ\'\'=γ\') foi de 0,05 (± 0,03) e a estimativa de sobrevivência aparente foi de 0,86 (± 0,06). As probabilidades de captura variaram entre as temporadas e os períodos secundários, com valores médios de 0,24 (± 0,02) no verão de 2015; 0,34 (± 0,03) no inverno de 2015; e 0,24 (± 0,03) no verão de 2016. Esses resultados sugerem que as variáveis ambientais entre as estações do ano têm pouco efeito sobre o tamanho da população local, a qual se encontra em equilíbrio e utiliza uma área ainda protegida de ameaças à sua perpetuação. / Reliable estimates of cetacean population parameters are necessary for effective management and conservation strategies. Capture-recapture methods have been commonly used to estimate demographic parameters because of their advantages and accuracy under a set of assumptions. The aim of this study was to estimate population parameters of Guiana dolphins, Sotalia guianensis, in the Cananeia estuary (25°03\' S; 47°55\' W) using capture-recapture models. The Pollock\'s robust design was used to estimate abundance, survival, temporary emigration and capture probabilities. Systematic boat-based photo-identification surveys were conducted in three seasons between Jan/2015 and Feb/2016. The best fitting model showed a population with constant survival, random temporary emigration and heterogeneous time-varying capture probabilities. Population sizes were of 430 (95% CI: 410-451) individuals in summer of 2015, 384 (95% CI: 366-403) individuals in winter of 2015 and 414 (95% CI: 392-438) individuals in summer of 2016. Temporary emigration rate (γ\'\'=γ\') was 0.05 (± 0.03) and apparent survival estimate was 0.86 (± 0.06). Capture probabilities varied greatly among seasons and secondary periods with mean values of 0.24 (± SE 0.02) in summer of 2015, 0.34 (± SE 0.03) in winter of 2015 and 0.24 (± SE 0.03) in summer of 2016. These results suggest that environmental variables between seasons have little effect on the size of the local population, which is stable and uses an area that is still protected from threats.
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Les blessés par accidents de la route : estimation de leur nombre et de leur gravité lésionnelle, France, 1996-2004

Amoros, Emmanuelle 20 December 2007 (has links) (PDF)
Les victimes d'accident de la route sont recensées par les forces de l'ordre, en France, et dans la plupart des pays. L'enregistrement des blessés non-décédés est incomplet et biaisé (biais de sélection et de classement de la gravité). Un registre médical couvre le département du Rhône. La coexistence des recensements policier et médical permet par capture-recapture d'estimer un bilan exhaustif au niveau rhodanien, et ainsi d'estimer les facteurs de correction des données policières. En faisant l'hypothèse d'homogénéité, sur le territoire national, des pratiques policières d'enregistrement des blessés, nous appliquons les coefficients de correction aux données policières nationales, en redressant sur les facteurs de biais. Les effectifs annuels moyens sur 1996-2004 sont alors estimés à 514 000 blessés dont 61 000 blessés graves, soit 3,7 et 2,2 fois les décomptes des forces de l'ordre. Les blessés avec séquelles lourdes sont estimés à 8000 annuellement, soit autant que les tués.
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Ecology of an island mouse, Apodemus sylvaticus hirtensis

Black, Thomas William January 2016 (has links)
An island subspecies endemic to the remote St Kilda archipelago, Apodemus sylvaticus hirtensis is considered of national importance but has been little studied, despite its inclusion in the criteria for the islands’ designation as a World Heritage Site. This study expands our knowledge of the core ecology of the mice; distribution, morphology, age structure, breeding phenology, population density, range size, survival and fecundity are all described and quantified using data collected from 4462 captures of 787 individuals between 2009-2012 on three sites (Carn Mor, Glen Bay & Village Bay), 1-2km apart on the main island of Hirta. Morphological analysis confirmed the reputed gigantism the mice, with maximum body weights of 60g for males and 50.5g for a non-gravid female both being approximately double that of a mainland specimen (the heaviest gravid female caught weighed 56g). Sexual dimorphism was evident, with males >1 year old being 8.7% heavier than females on average. Significant geographical variation in size was also found; mice on the seabird breeding colony of Carn Mor were heavier, longer and in better condition than mice elsewhere. Mice were observed to have a well-defined breeding season between April and September, shorter than on the mainland, with most individuals not breeding until their second year and very few surviving two winters. No geographical differences were found in the proportion of adult mice more than a year old that were in breeding condition at any given time, although there were significant geographical differences in the proportion of individuals in breeding condition for ‘young adult’ mice entering their first spring and sub adult mice in the autumn of the year in which they were. Spatially explicit capture-recapture (SECR) methods were used to quantify population densities free from ad hoc methods of trapping area estimation. Temporal variation in population size typical of temperate small mammals was found, with densities as low as 2 mice/ha in spring, increasing through summer and autumn with juvenile recruitment until reaching a peak at the beginning of winter of up to 50 mice/ha. Geographical variation was again observed, with frequent significant differences between trapping sites and an overall trend of highest population densities on the seabird breeding site. Mean individual range sizes varied between 0.3-3.0ha and were largest in Village Bay and in males in breeding condition. Pradel robust design recruitment models were used to quantify monthly survival (0.67-1.00) and fecundity (0.03- 0.41) and overall rate of population change (0.81-1.52) between sessions. Survival varied little between grids outside of the breeding season, but tended to be greater in Carn Mor than Village Bay during the summer. Fecundity rates varied little between years and grids, with one exception where increased summer fecundity followed a severe winter decline on Carn Mor. The possible role of differences in the quality of the food supply (in particular the seabird breeding colony and spatial variation in sheep grazing pressure) on creating geographical variation in body size, condition, breeding phenology, density and population dynamics are discussed in detail, as is the overall pattern of insular traits found in the mice.

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