Dans un contexte d'?volution incessante des moyens de communications sans fil, les inqui?tudes perdurent malgr? les l?gislations existantes. L'accroissement d'usages divers et vari?s des t?l?phones mobiles impliquent des questionnements sur l'exposition induite par ces nouveaux usages. Ce manuscrit permet d'enrichir les connaissances en dosim?trie num?rique en prenant en consid?ration la variabilit? des conditions d'utilisation. Pour une ?valuation pr?cise de l'exposition, la m?thode des Diff?rences Finies dans le Domaine Temporel (FDTD) qui a prouv? son efficacit?, est employ?e. L'objectif est de quantifier pr?cis?ment le D?bit d'Absorption Sp?cifique (DAS) induit dans des organes comme le cerveau et les organes reproducteurs. Dans cette analyse, une attention particuli?re sera port?e sur les usages potentiels des t?l?phones portables par les enfants. Le choix des configurations couvre diff?rentes technologies, usages et bandes de fr?quences permettant d'?tudier la sensibilit? du DAS ? la variabilit? de ces param?tres, pour une meilleure ma?trise de l'exposition r?elle, au-del? du probl?me de la conformit?. Le nombre important des variables oblige ? simplifier les mod?les de simulation par la construction de m?ta-mod?les statistiques afin de r?duire les co?ts de calcul. La m?thode spectrale par Chaos Polynomial (CP) d?di?e ? la gestion des incertitudes et ? l'analyse de sensibilit? est adopt?e pour la mise en place d'un mod?le approch? du DAS. Afin d'aboutir ? une repr?sentation par CP fiable et peu co?teuse en termes de simulations, l'utilisation par CP creux et adaptatif est appliqu?e. Seuls les termes les plus significatifs sont retenus dans la d?composition par CP. Cette approche est appliqu?e aux probl?mes en dosim?trie num?rique afin de propager les incertitudes portant sur les param?tres d'entr?e dans les simulations et de quantifier l'impact de ces incertitudes sur l'exposition (e.g. impact de la localisation du t?l?phone sur la dispersion du DAS) avec un faible co?t de calcul / Nowadays, wireless communication are being more and more developed, however, concern about their effects persist, despite of existing legislations. Indeed, the increasing use of mobile phone leads to address exposure issues to these devices. The objective of this thesis is to give better insights on numerical dosimetry, based on its configurations' variability. In order to evaluate the real exposure, we employ the well-known Finite-difference time-domain method (FDTD), which has already proven its efficiency. We aim at quantifying precisely the generated Specific absorption rate (SAR) on some human organs such as the brain and reproductive organs. In this work, we particularly focus, among other aspects, on the impact of mobile phones on children. We investigate different configurations involving various technologies, usages and frequency bands, such that we can study the SAR sensitivity to these parameters and, consequently, has the best possible estimate of the actual exposure level, independently of conformity issues. Due to the large number of parameters to be considered to deal with such an analysis, we simplify our simulation model by building statistical meta-models that enable us to reduce the calculation cost. Regarding the SAR modeling, we opt for Polynomial Chaos (PC) spectral methodology to deal with both uncertainty management and sensitivity analysis. To simplify the model and reduce simulation costs, we used parsimonious approximations, which aim to automatically identify the most significant terms in the PC decomposition, by a sparse and adaptive conception. Such approximations are applied to numerical dosimetry problems, where uncertainties are introduced on input parameters of the simulation and their impact is studied at the outputs, using low calculus cost. Using this approach, we analyze for example the position effect of the mobile phone on the SAR dispersion

Made available in DSpace on 2016-12-08T16:24:09Z (GMT). No. of bitstreams: 1 PGCA11MA078.pdf: 637847 bytes, checksum: a11da742649dfac9bb787886f73c49bf (MD5) Previous issue date: 2011-03-03 / The Brazilian caipira chickens are the result of random mating between different chicken breeds found in Brazil. They are characterized by their hardiness, disease resistance and the adverse conditions of climate and nutrition. In the 80, a change in consumption habits valued natural products, making theses chickens an alternative of great commercial value. However, its low productivity of this prevented the competition with the chicken industry. The output was the development of so-called caipira lines, chickens that blend the hardiness and resistance of native birds with the productivity of Brazilian poultry industry. In Brazil some of these commercial caipira chicken lines were developed, such as Paraíso Pedrês (beef) and Rubro Negra (posture). This study aimed to investigate the genetic variability nuclear and nonnuclear of Brazilian commercial caipira chickens lines through the analysis of ten microsatellite loci and the control region, D-loop, mitochondrial DNA (mtDNA). It was collected blood samples from 92 birds of Paraíso Pedrês lines (42) and Rubro Negrea (50). It was used the polymerase chain reaction technique (PCR) to amplify the samples and the amplified products were subjected to electrophoresis on an automated sequencer ABI 3130 DNA Genetic Analyzer. The number of alleles ranged from 3 (LEI0254) to 32 (LEI0212) for Paraíso Pedrês (PP) lines and 4 (LEI0254) to 31 (LEI0212) for Rubro Negra (RN) lines. The number of alleles per locus was 13,40 and 13,10 for PP and RN lines, respectively. Average expected heterozygosity was 0,824 for PP and 0,604 for RN. In the analysis of mtDNA, 100% of birds had PP haplotype 4, from Europe. In the RN line, haplotype 4 was found in 60% of the samples, the haplotype 3c in 10% and 30% in 3d haplotype, the haplotype 3c e 3d, from Asia. The results indicate that Brazilian lines of chickens examined, have a higher genetic variability observed in the typical commercial lines of chickens and the same was found for non-commercial poultry. For the formation of RN lines was used mostly birds of European origin and some of Asian origin. And for the composition of the PP lines were used only birds of European origin, at least as regards the maternal line / As galinhas caipiras brasileiras são o resultado de cruzamentos aleatórios entre diversas raças de galinhas encontradas no Brasil. Caracterizam-se pela sua rusticidade, resistência a doenças e as condições adversas de clima e alimentação. Nos anos 80, uma mudança nos hábitos de consumo valorizou os produtos naturais, tornando as galinhas caipiras alternativas de grande valor comercial. Porém, sua baixa produtividade inviabilizou a competição desta com a galinha industrial. A saída foi o desenvolvimento das chamadas linhagens caipiras, galinhas que mesclam a rusticidade e resistência das aves caipiras brasileiras com a produtividade das aves industriais. No Brasil foram desenvolvidas algumas destas linhagens, como a Paraíso Pedrês (corte) e a Rubro Negra (postura). Este trabalho teve como objetivo investigar a variabilidade genética nuclear e não nuclear de linhagens de galinhas caipiras brasileiras através da análise de dez lócus de microssatélites e da região controladora, alça-D, do DNA mitocondrial (mtDNA). Foram coletadas amostras de sangue de 92 aves das linhagens Paraíso Pedrês (42) e Rubro Negra (50). Foi utilizada a técnica de reação em cadeia pela polimerase (PCR) para a amplificação das amostras e os produtos amplificados foram submetidos à eletroforese em um sequenciador automático ABI 3130 DNA Genetic Analyser. O número de alelos variou de 3 (LEI0254) a 32 (LEI0212) para a linhagem Paraíso Pedrês (PP), e 4 (LEI0254) a 31 (LEI0212) para a linhagem Rubro Negra (RN). A média de alelos por loco foi de 13,40 e 13,10 para a linhagem PP e RN, respectivamente. A heterozigosidade média esperada foi de 0,824 para PP e 0,604 para RN. Na análise do mtDNA, 100% das aves PP possuíam o haplótipo 4, de origem Européia. Na linhagem RN, o haplótipo 4 foi encontrado em 60% das amostras, o haplótipo 3c em 10% e o haplótipo 3d em 30%, os haplótipos 3c e 3d são de origem Asiática. Os resultados obtidos indicam que as linhagens de galinhas caipiras brasileiras analisadas, apresentam uma variabilidade genética superior às observadas em linhagens comerciais típicas de galinhas e semelhante à observada em aves não comerciais. Para a formação da linhagem RN foi utilizado na sua maioria aves de origem Européia e algumas de origem Asiática. E, para a composição da linhagem PP, foi utilizado somente aves de origem Européia, pelo menos no que se refere à linhagem materna

Pentadesma butyracea Sabine est l’une des quatre espèces du genre Pentadesma endémique de l’Afrique. Elle est distribuée de la Sierra Léone au Gabon dans deux grands types d’habitats :les forêts denses humides discontinues du domaine guinéo-congolais (Haute- et Basse-Guinée) et le domaine soudanien du couloir sec du Dahomey (assimilé à une barrière à l’échange de gènes et d’espèces entre les deux blocs guinéo-congolais). Dans ce dernier, l’espèce se retrouve dans des galeries forestières et occupe une place capitale dans le développement socio-économique des communautés locales en raison des multiples biens et services que procurent ses produits (alimentation, médecine et pharmacopée traditionnelle, etc.). Cependant, des pressions d’origines multiples, telles que le ramassage des graines pour fabriquer du beurre, la fragmentation de l’habitat et sa destruction en faveur du maraîchage, les pratiques culturales inadaptées, les incendies, font peser de lourdes menaces sur l’espèce.<p>Le but de ce travail est d’acquérir les connaissances requises pour la conservation et la gestion durable des ressources génétiques de l’espèce. Trois objectifs ont été définis :(i) étudier la phylogéographie de l’espèce, (ii) étudier sa variabilité morphologique et génétique au Bénin et (iii) caractériser sa biologie de reproduction. En amont de ces travaux, nous avons développé onze marqueurs microsatellites nucléaires chez P. butyracea (chapitre 2). Ils ont été utilisés pour l’étude de la phylogéographie et la diversité génétique de P. butyracea (chapitres 3 et 5), ainsi que pour étudier la dépression de consanguinité et les paramètres de son système de reproduction (chapitre 7).<p>La caractérisation de la répartition spatiale des lignées génétiques de régions intergéniques de l’ADN chloroplastique et de l’ADN ribosomal (ITS) a détecté deux lignées génétiques allopatriques entre le Haut et le Bas-Guinéen, indiquant une forte différenciation génétique et un signal phylogéographique. L’analyse des microsatellites détecte trois pools géniques correspondant aux trois régions étudiées (Haute Guinée, Dahomey Gap et Basse Guinée). La diversité génétique est faible dans le Dahomey Gap, modérée dans le Haut-Guinéen et élevée dans le Bas-Guinéen. Ces résultats indiquent une séparation très ancienne des populations d’Afrique centrale et d’Afrique de l’ouest, alors que celles du Dahomey Gap pourraient résulter des forêts denses humides de l’Afrique de l’ouest lors de la période Holocène humide africaine. Dans ce couloir sec, les populations ont subi une forte dérive génétique, potentiellement due à des évènements de fondation. Au Bénin, deux groupes éco-morphologiques ont été détectés suivant un gradient nord-sud, contrastant avec deux pools géniques présentant une distribution est-ouest. <p>P. butyracea est une espèce auto-compatible majoritairement allogame. La corrélation de paternité est plus élevée aux niveaux intra-fruit vs. inter-fruits, et au sein d’une population de petite taille vs. de grande taille. Les principaux pollinisateurs au Bénin sont deux oiseaux (Cyanomitra verticalis, Cinnyris coccinigastrus) et trois abeilles (Apis mellifera, Meliponula togoensis, Hypotrigona sp.). La productivité totale en fruits augmente en fonction de l’âge de l’arbre et varie en fonction de l’année, atteignant un pic pour les arbres ayant un diamètre de 60-80 cm. Les graines sont récalcitrantes et ont une teneur en eau de 42.5 ± 2.9 %. <p>L’analyse des paramètres de reproduction et de diversité génétique, associés aux facteurs écogéographiques, nous a permis de proposer un échantillon de neuf populations représentatives de la diversité à l’échelle du Bénin, dans la perspective d’une conservation in situ. Le succès de celle-ci dépendra des efforts conjugués des communautés locales, de la recherche forestière et de la définition d’un cadre législatif par le politique pour la protection des habitats. La conservation ex situ est envisagée sous forme d’un verger rassemblant diverses origines, présentant l’intérêt supplémentaire de permettre d’étudier les contributions de la diversité génétique et de la plasticité phénotypique à la variation phénotypique. / Pentadesma butyracea Sabine is one of the four species of the endemic genus Pentadesma in Africa. The species is distributed from Sierra Leone to Gabon in two major types of habitats: the discontinuous and dense Guineo-Congolian rainforests (Upper and Lower Guinea) and the Sudanian domain of the dry corridor of Dahomey (considered as a barrier to the exchange of genes and species between Upper and Lower Guinea). In the latter, the species is found in gallery forests and plays a vital role in the socio-economic livelihood of local communities due to the various resources and services that provide its products (food, medicine and traditional, etc.). However, pressure from many sources including the collection of seeds to make butter, habitat fragmentation and its destruction for market gardening, inadequate agricultural practices, fires, are serious threats to the species.<p>The aim of this work was to acquire appropriate knowledge for the conservation and sustainable management of genetic resources of the species. Three objectives were defined (i) study the phylogeography of the species; (ii) evaluate its morphological and genetic variability in Benin; and (iii) characterize its reproductive biology. In a preliminary work, eleven nuclear microsatellite markers of P. butyracea were developed (Chapter 2). They were used for the study of phylogeography and genetic diversity of P. butyracea (chapters 3 and 5), and to study the inbreeding depression and parameters of its breeding system (Chapter 7).<p>The characterization of the genetic lineages and their spatial distribution using intergenic regions from chloroplast DNA and ribosomal DNA (ITS) region detected two allopatric genetic lineages between Upper and Lower Guinea, indicating a high genetic differentiation and a phylogeographic signal. Microsatellite markers allowed us to detect three genepools matching with the three studied regions (Upper Guinea, Dahomey-Gap and Lower Guinea). Genetic diversity was low in the Dahomey Gap, moderate in Upper Guinea and high in Lower Guinea. These results indicate an ancient separation of populations from Central and West Africa, while those from Dahomey Gap could originate West African rainforests (Upper Guinea) during the African humid Holocene period. In this dry corridor, populations experienced high genetic drift, possibly due to founding events. In Benin, two eco-morphological groups were detected following a north-south gradient, contrasting with two gene pools presenting an east-west distribution.<p>Pentadesma butyracea is a self-compatible, mainly allogamous species. The correlation of paternity was higher within-fruit vs. among-fruits, and in population of small size vs. large size. The main pollinators in Benin are two birds (Cyanomitra verticalis, Cinnyris coccinigastrus) and three bees (Apis mellifera, Meliponula togoensis, Hypotrigona sp.). Total productivity in fruit increases with tree age and varies yearly, reaching a peak for trees of 60-80 cm of diameter class. Seeds are recalcitrant (i.e. they cannot be conserved at low temperature), having a water content of 42.5 ± 2.9% at maturity.<p>The analysis of reproduction and genetics parameters, associated with eco-geographic factors, enabled us to select nine populations representative of the diversity in Benin, from the perspective of in situ conservation. The success of the latter will depend on combined efforts of local communities, forest research and an adequate legislative framework for the protection of habitats. Ex situ conservation is envisaged as an orchard assembling various origins, and would have the additional advantage of allowing to study the contribution of genetic diversity and phenotypic plasticity to phenotypic variation. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished