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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.
21

Evolution des troubles obsessionnels-compulsifs chez 9 enfants et adolescents traités par thérapie cognitive et comportementale et suivis pendant 18 mois / Improvement of obsessive-compulsive disorder in 9 children and adolescents treated by Cognitive-behavioral therapy and followed 18 months. (with a 18 months follow up)

Denis, Hélène 08 January 2011 (has links)
Le Trouble obsessionnel-compulsif (TOC) de l’enfant et de l’adolescent est un trouble fréquent mais encore peu reconnu. Le traitement de première intention est la thérapie cognitive et comportementale (TCC). Les objectifs de cette étude sont de démontrer la faisabilité d’un protocole de TCC en population clinique et de montrer l’évolution symptomatique pendant 18 mois. Neuf patients présentant un TOC âgés de 6 à 16 ans ont reçu 12 séances hebdomadaires de TCC. Une évaluation est réalisée avant et après le traitement puis tous les 6 mois pendant 18 mois, elle comprend la mesure des TOC (CY BOCS), également des symptômes anxieux (ECAP), de dépression (CDI), une échelle de fonctionnement global (C GAS) et d’amélioration (CGI). Trois subtests du WISC IV permettent d’analyser les capacités attentionnelles. Résultats : les patients s’améliorent de 46% à la CY BOCS après la TCC, de 69% à 18 mois. Les variations intra-individuelles montrent des profils évolutifs différents : réponse très rapide puis rémission, amélioration retardée suivie de rémission ou amélioration puis rechute. Un seul patient n’est pas répondeur. Un changement psychologique dans une optique différentielle et intra individuelle, par des techniques de ré échantillonage (Bootstrap) et de comparaison des profils (test de Kolmogorov-Smirnof) est observé pour les patients les plus sévèrement atteints initialement. Conclusions : Un protocole de TCC dans le TOC de l’enfant et de l’adolescent est réalisable en population clinique. L’efficacité est montrée et se poursuit pendant les 18 mois. La TCC permet une amélioration globale (CGI, C GAS), symptomatique (CY BOCS, ECAP, CDI) et cognitive (WISC IV). / Pediatric obsessive-compulsive disorder (OCD) is a frequent but a not usually recognized trouble. The first –line treatment is cognitive-behavioral therapy (CBT). Objective : To demonstrate the feasibility of CBT protocol delivered in an outpatient community-based clinic and to evaluate clinic symptoms at 18 months follow-up. Nine participants (age 6-16 years) received 12 CBT weekly sessions. Assessment is realized at pre and post treatment, and every 6 months during 18 months, including symptoms of TOC (CY BOC), of anxiety(ECAP), of depression ((CDI), global functioning (C GAS) and improvement (CGI). Three WISC IV subtests allow attentional capacity analysis. Results: patients improvements are : 46% at post treatment, and 69% at 18 months follow up. The intra-individual variations show differents evolutionary profiles : quick response and remission, delayed improvement followed by remission or improvement followed by relapse. Only one is non responder. A psychological change in a differential and intra-individual optical, with sample rate (Bootstrap) and profiles comparaison (test de Kolmogorov-Smirnof) is observed for the pre treatment more severe patients. Conclusions : CBT protocol of OCD in children and adolescent is feasible in community-base clinic. Efficiency is showed and continues during 18 months. CBT allows global (CGI, C GAS), symptom (CY BOCS, ECAP, CDI) and cognitive (WISC IV) improvements.
22

Ecology and Evolution of Adaptive Morphological Variation in Fish Populations

Svanbäck, Richard January 2004 (has links)
<p>The work in this thesis deals with the ecology and evolution of adaptive individual variation. Ecologists have long used niche theory to describe the ecology of a species as a whole, treating conspecific individuals as ecological equivalent. During recent years, research about individual variation in diet and morphology has gained interest in adaptive radiations and ecological speciation. Such variation among individual niche use may have important conservation implications as well as ecological and evolutionary implications. However, up to date we know very little about the extension of this phenomenon in natural populations and the mechanisms behind it.</p><p>The results in this thesis show that the extension of individual diet specialization is widely spread throughout the animal kingdom. The variation in diet is mainly correlated to morphological variation but not always. Furthermore, this variation in diet and morphology among individuals could be both genetically determined and environmentally induced and it mainly comes from trade-offs in foraging efficiency between different prey types. </p><p>The results from a number of studies of perch also show that individual perch differ in morphology and diet depending on habitat, where littoral perch has a deeper body compared to pelagic perch. This difference in morphology corresponds to functional expectations and is related to foraging efficiency trade-offs between foraging in the littoral and pelagic zone of a lake. The variation in morphology in perch is mainly due to phenotypic plasticity but there are also small genetic differences between the littoral and pelagic perch. Two separate studies show that both predation and competition may be important mechanism for the variation in morphology and diet in perch.</p><p>In conclusion, the results in this thesis show that individual variation in diet and habitat choice is a common phenomenon with lots of ecological and evolutionary implications. However, there are many mechanisms involved in this phenomenon on which we are just about to start learning more about, and only further research in this area will give us the full insight.</p>
23

Clone History Shapes the Populus Drought Transcriptome

Raj, Sherosha Joan Sharmila 15 February 2010 (has links)
The genus Populus is ideally suited to investigate questions related to the interplay between an individual’s environmental history and its capacity to respond to external stimuli. In order to dissect the influence of individual history on subsequent plant responses, transcriptome level changes due to water deficit were assessed in clonal populations of Populus hybrids. Results indicate variation in the drought transcriptomes of genetically identical clones originating from different locations can be shaped by the individual history of the clone. Additionally, yearly variations in drought transcriptome patterns showed specific trends associated with a clonal population that were not related to an unknown influence at a location, nor with the biological source of cuttings. Despite these sources of transcriptome variation, a common shared response was identified across all populations. The findings hint at the influence of the environment and epigenetic factors in the dynamic regulation of transcriptome level responses in clonal individuals.
24

Clone History Shapes the Populus Drought Transcriptome

Raj, Sherosha Joan Sharmila 15 February 2010 (has links)
The genus Populus is ideally suited to investigate questions related to the interplay between an individual’s environmental history and its capacity to respond to external stimuli. In order to dissect the influence of individual history on subsequent plant responses, transcriptome level changes due to water deficit were assessed in clonal populations of Populus hybrids. Results indicate variation in the drought transcriptomes of genetically identical clones originating from different locations can be shaped by the individual history of the clone. Additionally, yearly variations in drought transcriptome patterns showed specific trends associated with a clonal population that were not related to an unknown influence at a location, nor with the biological source of cuttings. Despite these sources of transcriptome variation, a common shared response was identified across all populations. The findings hint at the influence of the environment and epigenetic factors in the dynamic regulation of transcriptome level responses in clonal individuals.
25

Interactions between Pigmy Rattlesnakes (<i>Sistrurus miliarius</i>) and a Suite of Prey Species: A Study of Prey Behavior and Variable Venom Toxicity

Smiley-Walters, Sarah Ann 24 May 2017 (has links)
No description available.
26

Environnement physique et environnement social : conséquences physiologiques de la sélection des habitats

Chrétien, Emmanuelle 10 1900 (has links)
La sélection des habitats est un comportement important reliant des individus aux conditions environnementales de leur habitat. Elle est généralement étudiée pour faire des inférences sur les patrons de distribution des populations. Or, la sélection des habitats peut varier entre individus d’une même population et cette variation peut excéder la variation observée entre les populations. D’une part, si la sélection des habitats est adaptative, on peut supposer que les individus sélectionneront des habitats leur permettant de maximiser leur performance. D’autre part, les conditions environnementales dans les habitats peuvent affecter les performances individuelles, impliquant ainsi que la sélection des habitats peut avoir des conséquences physiologiques. Par ailleurs, l’environnement social peut influencer la performance physiologique des individus. L’objectif général de la thèse est l’étude des déterminants et des conséquences physiologiques de la sélection des habitats chez les poissons. Dans un premier temps, nous avons créé et comparé la capacité prédictive de modèles de sélection des habitats pour l’achigan à petite bouche Micropterus dolomieu intégrant la variabilité individuelle. Nos résultats ont démontré que l’intégration de la variabilité individuelle permettait d’identifier les variables influençant la sélection des habitats au niveau individuel, des groupes et de la population. Les modèles incluant les variables représentant la présence de refuges dans les habitats avaient un meilleur pouvoir prédictif que ceux qui ne les incluaient pas. Par ailleurs, des groupements d’individus présentant des similitudes dans leur sélection d’habitats ont été identifiés. Malgré tout, la variabilité dans la sélection des habitats entre les individus était nettement plus grande que la variabilité entre les groupes. Nous avons démontré que la présence de refuge était la variable la plus importante à considérer dans les modèles de sélection d’habitats pour les achigans à petite bouche. Nous avons ensuite investigué si la présence de refuge pouvait influencer différents traits métaboliques des achigans à petite bouche grâce à des expériences de respirométrie en laboratoire. La présence de refuge a diminué les taux métaboliques au repos (RMR) des achigans provenant d’un lac alors qu’il n’y a pas eu d’effet sur les achigans provenant d’une rivière. En considérant la position hiérarchique des individus, nous avons noté que les individus dominants avaient un temps de récupération plus court en présence de refuge alors que la présence de refuge n’a rien changé pour les individus soumis. Finalement, nous avons étudié si l’environnement social, en particulier la taille du groupe social, pouvait influencer l’estimation des taux métaboliques des poissons en présence ou en absence de refuge. Nous avons cette fois mené des expériences sur des vairons Phoxinus phoxinus, des poissons très sociaux. Les vairons gardés en petits groupes avaient des taux métaboliques plus élevés que ceux gardés en grands groupes. La présence de refuge a diminué les taux métaboliques indépendamment de la taille des groupes. Nos résultats ont démontré que la taille des groupes peut influencer les dépenses énergétiques des individus, ce qui souligne l'importance de comprendre le rôle des dynamiques sociales sur les variations dans les traits métaboliques. Les résultats de la thèse démontrent l’importance de tenir compte de l’environnement physique et de l’environnement social pour mieux comprendre les conséquences physiologiques de la sélection des habitats. / Habitat selection is an important behaviour that relates individuals to the environmental conditions in their habitat, and is generally studied to infer population-level patterns of distributions. Habitat selection varies among individuals and there is growing evidence that individual differences often exceed population differences in habitat selection. On the one hand, if habitat selection is adaptive, it could be hypothesized that individuals would select habitats that would maximize their fitness. On the other hand, environmental conditions in habitats can have physiological consequences, which can be amplified or masked by the social environment. Therefore, the general objective of this thesis was to better understand the determinants and physiological consequences of habitat selection. We created and compared the predictive capacity of habitat selection models for smallmouth bass Micropterus dolomieu integrating individual variability. Our results show that by integrating individual variability, we could identify variables influencing individual-, group-, and population-level habitat selection. Models that included variables referring to presence of shelter had the best predictive capacity. Further, we identified groups of individuals defined by their habitat selection. Nevertheless, variation in habitat selection among individuals was higher than that among groups. Presence of shelter was the main correlate of habitat selection for smallmouth bass. We then we tested whether presence of shelter could influence smallmouth bass metabolic traits estimated during respirometry trials. In presence of shelter, resting metabolic rates (RMR) were lower than in absence of shelter for smallmouth bass from a lake population. There was no difference in RMR for smallmouth bass from a river population. Further, dominant individuals showed reduced recovery time (RT) in presence of shelter, while no difference was observed in subordinate individuals. We investigated how social group size and availability of shelter could influence metabolic rate. This project was conducted on Eurasian minnow Phoxinus phoxinus, a highly social fish. Fish held in smaller groups had higher standard metabolic rate as compared to that of fish held in larger groups. Presence of shelter during respirometry trials was associated with reduced metabolic rates, regardless of group size fish were held in. Our results suggest that social group size may directly influence energy demands of individuals, highlighting the importance of understanding the role of group size on variations in physiological traits associated with energy expenditure. Our results highlight the importance of considering the physical and social environment to better understand the physiological consequences of habitat selection.

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