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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.
351

Analyse statistique de la diversité en anthropometrie tridimensionnelle / Statistical analysis of diversity in three-dimensional anthropometry

Kollia, Aikaterini 13 January 2016 (has links)
L’anthropométrie est le domaine scientifique qui étudie les dimensions du corps humain. La complexité de la morphologie du corps nécessite une analyse 3D, aujourd’hui permise par les progrès des scanners 3D. L’objectif de cette étude est de comparer les populations et utiliser les résultats pour mieux adapter les produits sportifs à la morphologie des utilisateurs. Des campagnes de mensuration 3D ont été réalisées et des algorithmes de traitement automatique ont été créés pour analyser les nuages de points des sujets scannés. Basés sur les méthodes d’images et de géométrie, ces algorithmes repèrent des points anatomiques, calculent des mesures 1D, alignent les sujets scannés et créent des modèles anthropométriques 3D représentatifs des populations. Pour analyser les caractéristiques anthropométriques, des statistiques de premier ordre et factorielles ont été adaptées pour être utilisées dans l’espace 3D. Les méthodes ont été appliquées à trois parties : le pied, la tête et la poitrine. Les différences morphologiques entre les populations, mais également au sein d’une population donnée, ont été révélées. Par exemple, la différence à chaque point de la tête entre des têtes a été calculée. Les statistiques en trois dimensions ont aussi permis de mettre en évidence l’asymétrie de la tête. La méthode de création de modèles anthropométriques est plus adaptée à nos applications que les méthodes dans la littérature. L’analyse en trois dimensions permet d’obtenir des résultats qui ne sont pas visibles par les analyses 1D. Les connaissances acquises par cette étude sont utilisées pour la conception de différents produits vendus dans les magasins DECATHLON à travers le monde. / Anthropometry is the scientific field that studies human body dimensions (from the greek άνθρωπος (human) + μέτρον (measure)). Anthropometrical analysis is based actually on 1D measurements (head circumference, length, etc). However, the body’s morphological complexity requires 3D analysis. This is possible due to recent progress of 3D scanners. The objective of this study is to compare population’s anthropometry and use results to adapt sporting goods to user’s morphology. For this purpose, 3D worldwide measurement campaigns were realized and automated treatment algorithms were created in order to analyze the subjects’ point cloud. Based on image processing methods and on shape geometry, these algorithms detect anatomical landmarks, calculate 1D measurements, align subjects and create representative anthropometrical 3D models. In order to analyze morphological characteristics, different statistical methods including components’ analysis, were adapted for use in 3D space. The methods were applied in three body parts: the foot, the head and the bust. The morphological differences between and inside the populations were studied. For example, the difference in each point of the head, between Chinese and European head, was calculated. The statistics in three dimensions, permitted also to show the asymmetry of the head. The method to create anthropometrical models is more adapted to our applications than the methods used in the literature. The analysis in three dimensions, can give results that they are not visible from 1D analyses. The knowledge of this thesis is used for the conception of different products that they are sold in DECATHLON stores around the world.
352

Fast timescales in stochastic population dynamics

Constable, George William Albert January 2014 (has links)
In this thesis, I present two methods of fast variable elimination in stochastic systems. Their application to models of population dynamics from ecology, epidemiology and population genetics, is explored. In each application, care is taken to develop the models at the microscale, in terms of interactions between individuals. Such an approach leads to well-defined stochastic systems for finite population sizes. These systems are then approximated at the mesoscale, and expressed as stochastic differential equations. It is in this setting the elimination techniques are developed. In each model a deterministically stable state is assumed to exist, about which the system is linearised. The eigenvalues of the system's Jacobian are used to identify the existence of a separation of timescales. The fast and slow directions are then given locally by the associated eigenvectors. These are used as approximations for the fast and slow directions in the full non-linear system. The general aim is then to remove these fast degrees of freedom and thus arrive at an approximate, reduced-variable description of the dynamics on a slow subspace of the full system. In the first of the methods introduced, the conditioning method, the noise of the system is constrained so that it cannot leave the slow subspace. The technique is applied to an ecological model and a susceptible-exposed-infectious-recovered epidemiological model, in both instances providing a reduced system which preserves the behaviour of the full model to high precision. The second method is referred to as the projection matrix method. It isolates the components of the noise on the slow subspace to provide its reduced description. The method is applied to a generalised Moran model of population genetics on islands, between which there is migration. The model is successfully reduced from a system in as many variables as there are islands, to an effective description in a single variable. The same methodology is later applied to the Lotka-Volterra competition model, which is found under certain conditions to behave as a Moran model. In both cases the agreement between the reduced system and stochastic simulations of the full model is excellent. It is stressed that the ideas behind both the conditioning and projection matrix methods are simple, their application systematic, and the results in very good agreement with simulations for a range of parameter values. When the methods are compared however, the projection matrix method is found in general to provide better results.
353

Space use in a population of least chipmunks in the Southwest Yukon

Glennie, Linda Cuffableness January 1988 (has links)
This thesis describes an investigation of space use in least chipmunks at Kluane Lake, in the southwest Yukon. I examined demography, home range and habitat use patterns in the population. Based on live-trapping data from two grids over two summers, mean number of animals on the study area was 22.6/grid, similar to chipmunk numbers measured there over the previous four years. The population was lower than is generally found in the same species further south, although year-to-year stability was typical. Chipmunks preferred open forest and shrub-land to closed-canopy forest, which is also typical of the genus. Home range sizes measured using telemetry averaged 4.86 ha, higher than in any previously published study of the genus. I examined the relationship between social spacing and space use. Home range overlap averaged 93.4%; chipmunks do not appear to defend exclusive core areas. Provoked interactions among neighbours suggested that social dominance was based on age, weight, and breeding condition, rather than ownership of space. Although provoked interactions were generally aggressive, the telemetry data suggest that such behaviour was artifactual. Comparing the encounter frequency of radio-collared animals to that generated by a random model showed that chipmunks avoided encounters, except when harvesting seasonally abundant food. Grid-trapping did not increase food or cover availability enough to affect home range size. There was evidence that the presence of traps affected use distribution but not enough to invalidate trap-based home range estimates. Comparison of trap and telemetry based estimates of home range size yielded no significant differences. / Science, Faculty of / Zoology, Department of / Graduate
354

Dopady populační politiky Číny / The impacts of China's population policy

Vargovčíková, Lucie January 2013 (has links)
The diploma thesis deals with the impacts of China's population policy. Thesis is divided into three main chapters. The first one discusses the characteristics of population policy in general, mainly the concept and definition of population policy's types and instruments and also the current practices in the world. The second chapter deals with the characteristics of population policy in China from the historical point of view. There is also a description of the registration system "hukou" and exemptions from the population policy. The second chapter also describes the impacts of China's population policy. The last chapter is devoted to the population aging with an explanation of aging in China and comparison of aging in China with aging in Japan.
355

Development and Testing of the Elderly Social Vulnerability Index (ESVI): A Composite Indicator to Measure Social Vulnerability in the Jamaican Elderly Population

Crooks, Donneth 27 February 2009 (has links)
Over the last two decades social vulnerability has emerged as a major area of study, with increasing attention to the study of vulnerable populations. Generally, the elderly are among the most vulnerable members of any society, and widespread population aging has led to greater focus on elderly vulnerability. However, the absence of a valid and practical measure constrains the ability of policy-makers to address this issue in a comprehensive way. This study developed a composite indicator, The Elderly Social Vulnerability Index (ESVI), and used it to undertake a comparative analysis of the availability of support for elderly Jamaicans based on their access to human, material and social resources. The results of the ESVI indicated that while the elderly are more vulnerable overall, certain segments of the population appear to be at greater risk. Females had consistently lower scores than males, and the oldest-old had the highest scores of all groups of older persons. Vulnerability scores also varied according to place of residence, with more rural parishes having higher scores than their urban counterparts. These findings support the political economy framework which locates disadvantage in old age within political and ideological structures. The findings also point to the pervasiveness and persistence of gender inequality as argued by feminist theories of aging. Based on the results of the study it is clear that there is a need for policies that target specific population segments, in addition to universal policies that could make the experience of old age less challenging for the majority of older persons. Overall, the ESVI has displayed usefulness as a tool for theoretical analysis and demonstrated its potential as a policy instrument to assist decision-makers in determining where to target their efforts as they seek to address the issue of social vulnerability in old age. Data for this study came from the 2001 population and housing census of Jamaica, with multiple imputation for missing data. The index was derived from the linear aggregation of three equally weighted domains, comprised of eleven unweighted indicators which were normalized using z-scores. Indicators were selected based on theoretical relevance and data availability.
356

Assessing the palliative care needs of elderly patients seen at the University College Hospital, Ibadan, Nigeria

Omoyeni, Eunice Nkechi 19 February 2021 (has links)
Background Nigeria, with a population growth rate (2000-2005) of 2.5% and with 5% of the total population aged 60 years and above, has the potential for a rapid growth rate of the older population in coming years.1 The implication of this in a country with large population as reported by the National Population Census 2006, limited number of health care professionals and care homes, is difficulty in meeting the various needs of the elderly, hence, the importance of identifying the palliative care needs of the elderly. Aim The study was set out to assess the palliative care needs of and provision of care to elderly patients seen in the selected clinics of the University College Hospital, Ibadan, Oyo state, Nigeria. Objectives 1. To describe characteristics of elderly patients seen in the selected clinics. 2. To explore the current use of the hospital palliative care team in the care of geriatric patient. 3. To explore the current use of the hospital palliative care team in the care of geriatric patient. Methods A descriptive cross-sectional study was conducted over a 3-month period using an interviewer administered questionnaire after full consent was given by participants. The questionnaire was a combination of the Africa Palliative Care Outcome Scale (APCA-POS), the Edmonton Symptom Assessment Scale (ESAS) and Hope Spiritual Assessment Tool. Demographic information regarding gender, age, nationality, abode and referral to the Care Centre was obtained. Scaled questions from selected tools were ticked with respect to physical, psychosocial and spiritual needs and expectations of palliative care. The validated data collection tools (APCA-POS, ESAS, HOPE) were used in the questionnaire. Ethical approval was obtained from the relevant organizations. Data was analysed using IBM SPSS statistics 21. Results 424 participants completed the questionnaire and most patients (330; 77.8%) were recruited from the geriatric wards with a 2:1 female to male ratio. Most participants fell in the 60 -69 year-old age group. The most common symptom was pain in 240 patients with moderate pain in single or multiple areas. A high percentage (45.8%) were moderately worried about their disease condition and only 66 out of 422 freely discussed this feeling with their family members. Other symptoms observed were nausea, vomiting, constipation and loss of appetite. Conclusion The study showed the palliative care needs of the elderly and calls for collaboration between the palliative care team and the physicians in the geriatric unit for better management of the needs of the elderly.
357

Vliv klimatické změny na ptačí populace v České Republice / Impact of Climate Change on Czech Bird Populations

Telenský, Tomáš January 2018 (has links)
Charles University, Faculty of Science Institute for Environmental Studies Doctoral study programme: Environmental Sciences Summary of the Doctoral thesis Impact of Climate Change on Czech Bird Populations Vliv klimatické změny na ptačí populace v České Republice Mgr. Tomáš Telenský Supervisor: doc. Mgr. Jiří Reif, Ph.D. Prague, 2018 Abstract Climate change is one of the most important drivers of biodiversity. If it proceeds at current pace, it will lead to homogenization and pose a serious threat to biodiversity. Birds, as one of the most researched taxonomic groups, are successfully used as indicators of biodiversity of the whole ecosystems, and thus offer an excellent opportunity to study the overall impact of climate change. We use data from repeated annual monitoring programmes in Czech Republic, Breeding Bird Monitoring Programe, based on point counts, and Constant Effort Sites mist- netting ringing programme, capture-mark-recapture schema. We found that: 1. Population growth of 6 out of 37 resident species responded negatively to seasons with lower winter temperatures. The response was stronger in species feeding on animals. 2. Long-distance (LD) migrants' breeding productivity responds negatively to higher spring temperatures and advanced spring as indicated by earlier leaf unfolding of three tree...
358

Évaluation de l’incidence des évènements indésirables sous traitement antipsychotique à partir d’une étude nationale multicentrique prospective en population pédiatrique naïve : étude ETAPE / Evaluation of the adverse events incidence on antipsychotic treatment from a prospective national multicenter study in naïve pediatric population : ETAPE Study

Menard, Marie Line 21 December 2018 (has links)
Introduction : Dans la population pédiatrique, la prescription des antipsychotiques (AP) connait une hausse majeure ces quinze dernières années malgré une Autorisation de Mise sur le Marché (AMM) française limitée à quelques molécules AP avec des indications réduites. Cela conduit à un taux de prescription hors AMM important avec des modalités de prescription dépendantes du prescripteur en l’absence de recommandations de prescription et de surveillance. De plus, la littérature relève un nombre inquiétant d’événements indésirables (EI) associé à un manque de données sur les conséquences à moyen et long terme. Méthode : L’étude ETAPE nationale, multicentrique, prospective a été financée par l’Agence Nationale de Sécurité du Médicament et des produits dérivés. L’objectif principal était de déterminer le taux d’incidence des EI au cours d’un suivi de 12 mois chez des enfants et des adolescents de 6 à 18 ans exposés pour la première fois à un AP quel que soit le motif de la prescription. Le suivi proposé était de 12 mois avec 5 visites (à l’inclusion, puis à 3, 6, 9 et 12 mois). Une recherche exhaustive des EI a été réalisée à chaque visite grâce à la passation d’échelles cliniques, un examen physique et des bilans complémentaires. Résultats : L’étude a débuté en Avril 2013, la période d’inclusion s’est étendue sur deux ans et le suivi s’est terminé en Avril 2016. Au total, 200 patients ont été inclus. Les données de 190 patients ont été analysées. L’âge moyen était de 12 ± 2,99 ans, avec une proportion de 75% de garçons. A l’inclusion, 91% des patients ont reçu un AP en monothérapie et 9% au moins deux psychotropes. Rispéridone et aripiprazole étaient les AP les plus prescrits. Parmi les prescriptions d’AP, 20,5% répondaient à une AMM. Parmi les EI potentiellement attribuables à l’AP : 15,4% étaient neuromoteurs, 14,8% gastroentérologiques, 12,2% métaboliques et 11,8% étaient des symptômes généraux. Le taux d’incidence des EI était de 11,52 EI par personne-année (IC 95% [9,83 ; 13,20]). Chez les 108 patients avec un suivi complet de 12 mois, 52,7% des EI sont apparus au cours du premier trimestre d’exposition (représentés principalement par les EI généraux et hormonaux). Néanmoins, l’apparition des EI était observée pendant toute la durée du suivi. Parmi ces patients, 25,8 % ont présenté au moins un EI sévère ou extrêmement sévère. De plus, la présence des EI s’est révélée stable au cours des 12 mois. Conclusion : Ce travail a contribué à mettre en évidence dans une population naïve pédiatrique nationale un fort taux d’incidence d’EI et un taux d’apparition et de présence des EI stable sur 12 mois. La présence d’EI sévères a touché un quart de la population ayant complété le suivi. Perspectives : Sur un échantillon de 55 patients niçois nous chercherons l’impact du polymorphisme génétique des cytochromes dans le métabolisme des AP et sur l’apparition des EI. L’ensemble de ces travaux a pour objectif de contribuer à la mise en place de recommandations de prescription et de surveillance des paramètres cliniques, biologiques et électrocardiographiques lors de l’introduction d’un AP en population pédiatrique pour améliorer la balance bénéfice/risque. / Background In France, as in the rest of the world, the off-label prescription of antipsychotics is on the rise in the pediatric population. In the literature, we noticed a significant lack of data on drug safety and adverse events in the naïve pediatric population treated by antipsychotic in the short as well as in the long term. In addition, studies independent of pharmaceutical laboratories are lacking. Method ETAPE Study was a naturalistic prospective multicenter study conducted between April 2013 and May 2016. Type of AP, concomitant treatment, clinical evaluation and AEs were registered at inclusion and 3-, 6-, 9- and 12-months follow up. This trial is registered with ClinicalTrials.gov, number NCT02007928. The main objective was to determine the incidence rate of adverse events (AEs) in the antipsychotic-naïve pediatric population treated by antipsychotic (AP) during a 12-months. Outcomes A total of 190 patients were analyzed. The mean age was 12 ± 2.99 years, with 75% being males. At baseline, 91% of patients received AP monotherapy and 9% received at least two psychotropic drugs. Risperidone and aripiprazole were the most frequently prescribed AP. 20.5% of prescriptions were in label. Among the AEs potentially attributable to AP, 15.4% were neuromotor, 14.8% gastroenterological, 12.2% metabolic and 11.8% general symptoms. The overall incidence rate was 11.52 AE per person-years (IC 95% [9.83; 13.20]). In patients completing completed FU (n=108), 52.7% of AEs appeared during the first 3 months, but onset of AE was noted during the 12-months FU. 25.8 % of patients have been exposed to at least one severe or extreme severity AE. The persistence of AEs was stable during the 12-months FU.Interpretation The high incidence rate of AEs, the severity and the persistence of AEs justify the necessity of clinical and biological follow-up of AEs during at least 12-months of AP treatment.
359

Evaluating Bat Roost Abundance: A Comparison of Drone-Acquired Thermal Imagery and Acoustic Estimates with Visual Observations

Jaffe, Karah 01 August 2022 (has links)
Roosts provide an opportunity to census philopatric populations of bats. Comparing the efficacy of traditional methods with novel methods can provide guidance on the use of new technologies in the field. This project aims to compare the count efficacy of external emergence methodologies, i.e., drone-acquired thermal imagery, acoustic estimates, and visual counts. Surveys were conducted ten nights at two emergence sites and synchronized to compare counts. Acoustic estimates could not be established as there was a weak prediction of the linear relationship between root-mean-square pressure and emergence count; therefore, this method was removed from the comparative analysis. A linear mixed-effects model and Bonferroni correction found a significant difference in visual and thermal methods at the eastern Tennessee site. Additionally, there was an overall median similarity of 92% from counts obtained from the compared methods. This study supports the validity of drone-acquired thermal imagery for external emergence counts.
360

Population Structure in the Cincinnati area

Baric, Michelle B. 15 October 2013 (has links)
No description available.

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