Les bactéries, organismes les plus abondants de notre planète, ont un rôle fondamental dans le fonctionnement des écosystèmes. En dépit de leur importance, la caractérisation des communautés bactériennes (microbiotes) demeure encore aujourd’hui très incomplète. Ceci a pour origine l’impossibilité de complètement décrypter taxonomiquement et fonctionnellement les microbiotes de ces écosystèmes et donc à appréhender la diversité bactérienne dans son ensemble que ce soit par des approches culturales (avec seulement 1% de bactéries cultivables) ou par des approches metagénomiques limitées par les biais d’extraction, de séquençage et d’analyse. Les travaux entrepris dans le cadre de cette thèse visent à développer une nouvelle voie exploratoire passant par le fractionnement des microbiotes afin d’en étudier séparément les génomes des différentes populations ou groupes de populations, leur somme devant permettre de reconstituer un metagénome complet. Cet objectif requiert le développement d’un outil pour la sélection spécifique de bactéries (sur des critères taxonomiques ou fonctionnels) et leur isolement du reste des microorganismes non ciblés. Les travaux de thèse ont porté sur le développement d’une approche de marquage magnétique des bactéries basée sur l’hybridation moléculaire (hybridation in situ) complétée par celui d’un outil de tri microfluidique. Deux méthodes ont été développées, MISH et HCR, ciblant le gène de l’ARNr 23S, chacune reposant sur la formation, lors du processus d’hybridation, d’une structure secondaire en arborescence (MISH) ou ordonnée (HCR) permettant le greffage de nanoparticules magnétiques. Les résultats obtenus illustrent le potentiel des deux approches d’abord pour le marquage spécifique de bactéries cibles (E.coli et Pseudomonas putida) en conditions de culture au laboratoire puis dans un second temps dans des échantillons de sol. Le tri microfluidique a également été optimisé par le développement d’un nouveau dispositif de tri magnétique permettant la séparation des cellules marquées sous flux continu faisant appel à l’injection d’un polymère composite magnétique pour intégrer au fond du microcanal une série de bandes parallèles magnétiques. La fonctionnalité du dispositif a été démontrée, sa simplicité de fabrication en faisant un outil de choix pour une application en routine dans les laboratoires d’écologie microbienne. En dépit de résultats prometteurs toute cette nouvelle approche d’étude de la diversité bactérienne environnementale nécessite encore de nombreuses étapes d’optimisation. / Bacteria, the most abundant organisms on our planet, have a fundamental role in ecosystem functioning. Despite their importance, the characterization of bacterial communities is today still incomplete. This is due to the impossibility of completely decomposing taxonomically and functionally the microbial communities of these ecosystems and as a consequence to apprehend the whole bacterial diversity, either by cultural approaches (with only 1% of culturable bacteria) or by metagenomic, a limited approaches cause by biases in extraction, sequencing and analysis. The work undertaken in this thesis aims to develop a new exploratory pathway through the fractionation of microbiota in order to study separately genomes of different populations or groups of populations. Their sum should enable reconstitution of complete metagenome. This objective requires the development of a tool for the specific selection of bacteria (on taxonomic or functional criteria) and their isolation from the rest of the non-target microorganisms. The thesis work focused on the development of a magnetic labeling approach for bacteria based on molecular hybridization (in situ hybridization) complete by development of a microfluidic cell-sorting tool. Two methods have been developed, MISH and HCR, targeting the 23S rRNA gene, each based on the formation, during the hybridization process, of a secondary random structure (MISH) or organized structure (HCR) enabling binding to magnetic nanoparticles. Results obtained illustrate the potential of the two approaches initially for the specific labeling of target bacteria (E.coli and Pseudomonas putida) under laboratory conditions and then in soil samples. The microfluidic sorting was also optimized by the development of a novel magnetic cell-sorting device allowing the separation of the labeled cells under continuous flow using the injection of a magnetic composite polymer to integrate a series of magnetic parallel strips at the bottom of the microchannel. The proper functioning of the sorting device has been demonstrated, its simple production making it a tool of choice for a routine application in laboratories of microbial ecology. Despite promising results all this new approach for studying environmental bacterial diversity is still requiring many optimization steps.

O objetivo deste estudo foi comparar modelos importantes de classificações de risco em barragens (Índice Global de Risco Modificado, USACE, COGERH e Resolução CNRH n° 143), empregados por instituições no Brasil e no Mundo, na forma padrão e utilizando adaptações para o método multicritério ELECTRE TRI. Propôs-se também um método que atendesse às especificidades do ELECTRE TRI com apoio de um decisor com conhecimento técnico em segurança de barragens. Essas classificações foram aplicadas nas barragens dos projetos de irrigação Rio Formoso e Manuel Alves sob gestão da SEPLAN - TO. Levantaram-se informações técnicas por meio de projetos executivos e visitas técnicas nas construções para a realização do enquadramento das barragens nas classificações, tanto para os métodos já existentes, como para o método proposto pelo estudo que utilizou especificamente o ELECTRE TRI. Para a barragem do projeto Rio Manuel Alves a classificação foi de Baixo Risco. As barragens do Projeto Rio Formoso apresentaram classificações de Alto Risco e Risco Extremo. / The objective of this study was to compare important models of risk classifications in dams (Global Modified Risk Index, USACE, COGERH and Resolution CNRH n ° 143), employed by institutions in Brazil and in the world, in the standard form and using adaptations to the method Multicriteria ELECTRE TRI. It was also proposed a method that would meet the specificities of ELECTRE TRI with the support of a decision maker with technical knowledge on dam safety. These classifications were applied to the dams of the Rio Formoso and Manuel Alves irrigation projects under the management of SEPLAN - TO. Technical information was obtained through executive projects and technical visits to the constructions for the implementation of the classification of dams in the classifications, both for the existing methods and for the method proposed by the study that specifically used ELECTRE TRI. For the Rio Manuel Alves dam, the classification was Low Risk. The Rio Formoso Project dams presented High Risk and Extreme Risk ratings.

Optical switchers can fulfill the same functions as all-electrical switching systems and are expected to play a key role in the near future. In this thesis an analysis if an optical system that can potentially behave as an optical switcher is discussed. This configuration consists of three microring resonators which are coupled and tangential to one another in a topology that is similar to the Leibniz packing or Apollonian gasket. The ray-transfer matrix approach is used in order to represent the whole system by a single matrix. The structure receives an initial input signal and gives an output signal, which is changed by only a scalar factor. This description is equal to an eigenvalue problem, where the matrix of the system operates over an initial vector and results a product of a scalar (the eigenvalue) times the initial vector. Due to its unique geometry each ring is divided into two unequal segments. We introduce the loss coefficients to express the attenuation along those segments. The relation between the loss coefficients is being examined and the results are verified by simulations.

Submitted by Mariana Dornelles Vargas (marianadv) on 2015-03-17T19:40:51Z No. of bitstreams: 1 metodo_quantificar.pdf: 1038017 bytes, checksum: 54f78fa2753a1dfe9d797dc88d1ed31e (MD5) / Made available in DSpace on 2015-03-17T19:40:51Z (GMT). No. of bitstreams: 1 metodo_quantificar.pdf: 1038017 bytes, checksum: 54f78fa2753a1dfe9d797dc88d1ed31e (MD5) Previous issue date: 2011-03-16 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / PROSUP - Programa de Suporte à Pós-Gradução de Instituições de Ensino Particulares / Em ambientes produtivos intermitentes que operam na condição ?produzir para estoque?, com fluxo convergente, a possibilidade de constituir estoques em processo (WIP), de produtos prontos, ou matérias-primas pode aumentar o grau de complexidade da gestão das operações e a necessidade de utilizar procedimentos de controle distintos para cada tipo de estoque. Ao focar no alinhamento da gestão dos estoques aos planos de demanda e capacidade, considerando um ambiente produtivo que emprega a abordagem Conwip, a presente pesquisa tem por finalidade propor um método estruturado que possibilite quantificar o nível de WIP do sistema produtivo, a partir da Simulação por Eventos Discretos e da técnica de Apoio Multicritério ELECTRE TRI. Esta pesquisa tem o intuito de contribuir com a geração de informações que subsidiem a tomada de decisão concernente à escolha de uma configuração de cenário que aluda a um nível de estoque em processo e de produtos prontos considerando o mix de produção sob estudo. Fundamentado na proposta desenvolvida nesta dissertação, o Método de Pesquisa pode ser caracterizado quanto aos procedimentos técnicos, pelo uso da Simulação Computacional e relativo à natureza dos dados, destaca-se o da abordagem essencialmente quantitativa, ou Pesquisa Quantitativa. O método proposto foi avaliado, quanto a sua estrutura e proposta, por especialistas das disciplinas de Simulação, Gestão de Sistemas Produtivos e Métodos Multicritério à Decisão. Uma aplicação do método em um sistema produtivo real também é apresentada / In intermittent productive systems that operate in the condition 'make to stock' with convergent flow, the possibility of generate work in process (WIP), finish good products or raw materials inventories can increase the degree of complexity of the management in the operations and the need of using procedures of different control for each stock type. Focusing in the alignment of the stocks to the demand and capacity plans, considering a productive system which uses the Conwip approach, this research describes a structured method that aims to quantify the level of WIP in the productive system, applying the Events Discrete Simulation and the technique nominated ELECTRE TRI. This research intends to contribute with the generation of information for decision support regarding the choice of work in process and finished goods stock levels, considering the production mix studied. Based in the proposal developed in this work, the Method of Research can be characterized, regarding the technical procedures, as Computational Simulation, and regarding the nature of the data, as Quantitative Research. The method proposed in this research was evaluated for specialists in the disciplines of Simulation, Administration of Production Systems and Multicriteria Decision Analysis. An application of the method in a real productive system is also presented.

À l'origine de cette thèse, nous nous sommes intéressés à l'algorithme de tri TimSort qui est apparu en 2002, alors que la littérature sur le problème du tri était déjà bien dense. Bien qu'il soit utilisé dans de nombreux langages de programmation, les performances de cet algorithme n'avaient jamais été formellement analysées avant nos travaux. L'étude fine de TimSort nous a conduits à enrichir nos modèles théoriques, en y incorporant des caractéristiques modernes de l'architecture des ordinateurs. Nous avons, en particulier, étudié le mécanisme de prédiction de branchement. Grâce à cette analyse théorique, nous avons pu proposer des modifications de certains algorithmes élémentaires (comme l'exponentiation rapide ou la dichotomie) qui utilisent ce principe à leur avantage, améliorant significativement leurs performances lorsqu'ils sont exécutés sur des machines récentes. Enfin, même s'il est courant dans le cadre de l'analyse en moyenne de considérer que les entrées sont uniformément distribuées, cela ne semble pas toujours refléter les distributions auxquelles nous sommes confrontés dans la réalité. Ainsi, une des raisons du choix d'implanter TimSort dans des bibliothèques standard de Java et Python est probablement sa capacité à s'adapter à des entrées partiellement triées. Nous proposons, pour conclure cette thèse, un modèle mathématique de distribution non-uniforme sur les permutations qui favorise l'apparition d'entrées partiellement triées, et nous en donnons une analyse probabiliste détaillée / At first, we were interested in TimSort, a sorting algorithm which was designed in 2002, at a time where it was hard to imagine new results on sorting. Although it is used in many programming languages, the efficiency of this algorithm has not been studied formally before our work. The fine-grain study of TimSort leads us to take into account, in our theoretical models, some modern features of computer architecture. In particular, we propose a study of the mechanisms of branch prediction. This theoretical analysis allows us to design variants of some elementary algorithms (like binary search or exponentiation by squaring) that rely on this feature to achieve better performance on recent computers. Even if uniform distributions are usually considered for the average case analysis of algorithms, it may not be the best framework for studying sorting algorithms. The choice of using TimSort in many programming languages as Java and Python is probably driven by its efficiency on almost-sorted input. To conclude this dissertation, we propose a mathematical model of non-uniform distribution on permutations, for which permutations that are almost sorted are more likely, and provide a detailed probabilistic analysis

In the Midwestern US, forested and other woody plant habitats are embedded in a matrix of agricultural and urban landcover that alters configurations of “natural” habitats and creates novel habitat types. Variation in the type and juxtaposition of landcover in the matrix between habitats can profoundly impact the spatial and temporal distributions of insects. Intense urban and agricultural development alters habitats, increases fragmentation, and may decouple trophic interactions if plants or animals cannot disperse to needed resources. Specialist insects represent a substantial proportion of global biodiversity and their fidelity to discrete microhabitats provides a powerful framework for investigating organismal responses to human land use. Specialist herbivores and parasitoids that depend on discrete plant habitats simplify assessment of how trophic interactions, local demographic traits, and dispersal processes affect responses to landcover heterogeneity. Herbivore responses to landcover change are highly idiosyncratic and not well characterized. Parasitoid wasps are predicted to be more prone than their herbivore hosts to local extinction in response to increased habitat fragmentation, but often respond differently to similar landcover contexts. Understanding and predicting idiosyncratic spatial population dynamics of simple host-parasitoid communities and other insect systems requires integration of metacommunity-level ecological paradigms with spatial analyses across multiple spatial scales. We sampled site occupancy and densities for two plant-herbivore-parasitoid systems from 250 sites across a 360 km2 urban/ agricultural landscape across three study years to ask whether and how human development decouples interactions between trophic levels. We first performed a single year analysis to investigate broad scale patterns. We compared patterns of site occupancy, host plant density, herbivory and parasitism rates of insects at two trophic levels with respect to landcover at multiple spatial scales. Geospatial analyses were used to identify landcover characters predictive of insect distributions. We found that herbivorous insect densities were decoupled from host tree densities in urban landcover types at several spatial scales. This effect was amplified for the third trophic level in one of the two insect systems: despite being abundant regionally, a parasitoid species was absent from all urban/ suburban landcover even where its herbivore host was common. Our results indicate that human land use patterns limit distributions of specialist insects. Dispersal constraints associated with urban built development are specifically implicated as a limiting factor. Our multi-year analysis of trophic interactions in urban versus agricultural landcover showed that important results from our single-year study are consistent over time and provided useful insights into the factors mediating spatial distributions of specialist insects in altered landscapes. While we observed that insect species responded to landcover at consistent local- and landscape-scale spatial extents, we observed that coarse grain landcover categories (i.e. urban versus agricultural) at low spatial resolution yielded the most consistent patterns of organismal response. Our results indicate that agricultural versus urban landcover contexts can mediate distinct spatial population structuring across linked trophic levels. This finding has important implications for conservation and pest management strategies in heterogeneous landscapes and is an important consideration when translating heuristics regarding metacommunity dynamics from one broad spatial context to another.

African American male ex-offenders struggle with lack of assistance during their transition from incarceration, and they encounter many barriers when released back into the community. The purpose of my general qualitative study was to explore the perceptions of whether the reentry program impacted African American male ex-offenders likelihood of recidivating within one year. The theoretical framework included labeling theory, social disorganization theory, and social learning theory. The population consisted of 60 African American male ex-offenders intake participants of a reentry program that all completed the Client Satisfaction Survey. A purposive random sampling method was used to select ten participants for in-depth interviews. Data were collected through responses on the Client Satisfaction Survey and qualitative interviews. The research question was addressed through inductive coding and thematic analysis. The findings indicated that the reentry program enhanced participants' well-being, improved their communication, and increased their resourcefulness. Findings may be used to develop and improve reentry programs to promote better reentry outcomes and safer communities.

Let (X1, X2, X3) be a tri-variate normal vector with a non-singular co-variance matrix ∑ , where for i ≠ j, ∑ij < 0 . It is shown here that it is then possible to determine the three means, the three variances and the three correlation coefficients based only on the knowledge of the probability density function for the minimum variate Y = min{X1 , X2 , X3 }. We will present a method for identifying the nine parameters which consists of careful determination of the asymptotic orders of various bivariate tail probabilities.

La polarité épithéliale est un processus essentiel au cours du développement d'un organisme. Ici, nous nous focalisons sur le tissu épithélial intestinal et épidermal de C. elegans pour comprendre comment la cellule maintient sa polarité en définissant un pôle apical et un pôle basolatéral. Afin d'assurer la mise en place et le maintien de cette polarité, des protéines appelées déterminants de polarité interviennent. Parmi ces déterminants, le module PAR-3/PAR-6/aPKC et CDC-42 sont des acteurs majeurs pour spécifier la polarité apicale. Nous avons montré que le complexe adaptateur pour la clathrine AP-1, un régulateur clé du trafic intracellulaire remplit une fonction inattendue dans ce processus. En effet, nous avons confirmé le rôle d'AP-1 dans le tri basolatéral observé chez les mammifères, mais de façon intéressante nous avons démontré qu'AP-1 contrôle également le tri apical d'une protéine transmembranaire ainsi que la localisation asymétrique apicale de CDC-42 et PAR-6. En effet, l'inhibition d'AP-1 cause une délocalisation basolatérale de CDC-42 et PAR-6. La perte de fonction d'AP-1 induit une conversion de la membrane latérale en membrane apicale et la formation de lumières intestinales ectopiques. La perte de fonction du complexe AP-1 induit également une létalité embryonnaire qui peut s'expliquer par le phénotype identifié dans l'épiderme. Dans cet épithélium, AP-1 contrôle l'intégrité des jonctions cellulaire et notamment le tri apical de la E-cadhérine. Nos résultats démontrent une fonction essentielle d'AP-1 dans le tri apical, directement responsable du maintien de la polarité épithéliale.

Si les pouvoirs publics ont en charge la gestion des déchets ménagers, la réussite de la politique de revalorisation repose sur l'adoption par chacun des pratiques domestiques adaptées. L'enjeu pour les institutions concernées est alors que le plus grand nombre participe au dispositif de tri mis en place. Pour ce, les collectivités territoriales multiplient les communications à destination de leurs administrés. Ces opérations d'information et de sensibilisation revêtent le plus souvent la forme d'une éducation au geste juste, ne favorisant pas la responsabilisation du citoyen. Par ailleurs, elles sont de forme persuasive et reposent sur l'hypothèse d'un homme rationnel qui agirait en fonction de ses idées, savoirs et croyances. Les liens entre attitudes et comportements sont aussi complexes que discutés ; de nombreuses études et arguments plaident en faveur d'un homme rationalisant. La psychologie de l'engagement s'inscrit dans ce paradigme et préconise la réalisation « libre » d'un comportement comme le meilleur prédicteur des comportements et attitudes futurs. Autrement dit, elle préconise l'obtention d'un acte préparatoire dans l'objectif d'obtenir de l'individu qu'il réalise à la suite le comportement attendu. Nous expérimenterons ici différentes techniques d'influence issues de ce paradigme. Des observations réalisées en marge de ces expériences nous conduiront à reconsidérer le modèle d'une influence unilatérale proposé par cette théorie. Aussi, en appréhendant les phénomènes d'influence dans leur complexité, nous développerons des modalités de communication participative au sein desquelles le sujet sera appelé à devenir acteur et l'administré à devenir citoyen