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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.
501

Propriété UMD pour les espaces de Banach et d'opérateurs

Qiu, Yanqi 13 December 2012 (has links) (PDF)
Cette thèse présente quelques résultats sur la théorie locale pour les espaces de Banach et d'opérateurs. La première partie consiste en l'étude de la propriété $\text{OUMD}$ pour l'espace colonne $C$. La deuxième partie traite de la propriété $\text{UMD}$ classique pour les espaces $L_p(L_q)$ itérés. Le résultat principal donne une construction nouvelle et très naturelle de treillis de Banach qui sont super-réflexifs et non-$\text{UMD}$: L'espace $L_p(L_q(L_p(L_q(\cdots$ itéré une infinité de fois est super-réflexif si $1 < p, q < \infty$ mais n'est pas $\text{UMD}$ si $p \ne q$.
502

Quelques modèles mathématiques de jonctions

Juntharee, Pongpol 09 November 2009 (has links) (PDF)
Cette thèse de doctorat est consacrée à l'étude mathématique de deux types de problèmes de jonction. Le premier modèle est obtenu comme limite variationnelle d'un problème d'élasticité avec jonction de faible épaisseur, l'adhésif occupant la jonction a une rigidité de l'ordre de l'épaisseur. La densité élastique W de l'adhésif est complétée par une densité d'énergie surfacique convexe h non nécessairement régulière. Cette densité traduit une contrainte mécanique entre adhérents et l'adhésif imparfaitement collés. On montre que le modèle limite consiste à remplacer la jonction par une contrainte qui est l'inf-convolution de h et de la densité surfacique limite de W. Dans un cadre scalaire on effectue l'analyse des concentrations de gradient à l'interface au moyen d'outils récents issus de la théorie de la mesure. Dans le second modèle, la rigidité de l'adhésif est de l'ordre inverse de l'épaisseur de le jonction, la densité élastique du matériaux adhérent a une croissance super-linéaire alors que celle de l'adhésif croit linéairement. Suivant la stratégie utilisée pour le premier problème on propose un modèle simplifié mais fiable comme limite variationnelle lorsque l'épaisseur tend vers zéro. A la limite la fine couche intermédiaire est remplacée par une interface pseudo-plastique prédisant la formation de fissures.
503

Renormalisation de la théorie quantique des champs en espace-temps courbes: une approche causale.

Viet Dang, Nguyen 12 December 2013 (has links) (PDF)
Le sujet de la thèse est la construction d'une théorie perturbative des champs quantiques en interaction sur un espace-temps courbe, suivant un point de vue conçu par Stueckelberg et Bogoliubov et developpé par Epstein-Glaser sur l'espace de Minkowski plat. En 2000, un progrès important fut réalisé par Brunetti et Fredenhagen qui réussirent à étendre la théorie d'Epstein-Glaser en exploitant le point de vue développé par Radzikowski pour définir les états quantiques sur un espace-temps courbe en terme d'ensembles de front d'onde. Ces résultats furent ultérieurement généralisés par Fredenhagen, Brunetti, Hollands, Wald, Rejzner, etc. aux théories de Yang-Mills et de la gravitation. Cependant, même pour des théories sans invariance de jauge, de nombreux détails mathématiques sont restés inexplorés et parfois sans vérification. Nous construisons d'une façon totalement rigoureuse cette théorie dans le cas des champs sans invariance de jauge. Dans notre travail, nous revisitons complètement cette théorie, résolvant au passage plusieurs questions laissées en suspens, incorporant de nombreux résultats nouveaux autour de ce programme et, le cas échéant, apportant des détails beaucoup plus précis sur les contre-termes dans le processus de renormalisation, une compréhension plus approfondie des ambiguïtés et une description géométrique des ensembles de front d'onde.
504

Commutateurs, analyse spectrale et applications

Golenia, Sylvain 03 December 2012 (has links) (PDF)
On présente tout d'abord la théorie des commutateurs positifs et ses développements récents. On discute ensuite les applications à la théorie spectrale des Laplaciens magnétiques sur les variétés, les opérateurs de Dirac singuliers et des opérateurs de Schroedinger à décroissance lente. On étudie ensuite les propriétés spectrales de divers Laplaciens discrets pour les questions de l'auto-adjonction et l'asymptotique des valeurs propres. Puis on présente des résultats liés au spectre absolument continu pour les opérateurs de Dirac discret en dimension 1. Enfin on caractérise les chemins hamiltonien pour les échiquiers de grande dimension.
505

Analyse techno-fonctionnelle des industries à pièces bifaciales aux pléistocènes inférieur et moyen en Chine / Techno-functional analysis of biface-bearing industries in lower and middle pleistocene China

Bodin, Erika 18 January 2011 (has links)
Les industries à pièces bifaciales découvertes en Chine font actuellement l’objet d’interprétations opposées. L’une d’elle, de plus en plus souvent proposée, considère les pièces bifaciales chinoises comme les témoins d’une diffusion à partir de l’Occident. Le modèle traditionnel proposant un isolement technico-culturel de l’Asie de l’Est, matérialisé la « ligne de Movius », serait alors erroné. Ce regroupement des industries à pièces bifaciales chinoises au sein du complexe « acheuléen » ne fait pas l’unanimité et l’hypothèse d’une réinvention locale est également envisagée. Ces hypothèses contradictoires reflètent les lacunes des cadres méthodologiques et conceptuels employés pour l’étude de ces industries. L’approche retenue pour cette étude vise à restituer les intentions placées dans la réalisation de l’outillage par le biais d’une analyse techno-fonctionnelle. Les sites retenus appartiennent à une période comprise entre 1Ma et 500ka : Yangwu, Gaolingpo et Nanbanshan, dans le bassin de Bose (région autonome du Guangxi Zhuang) et les sites de Lantian et Liangshan Longgangsi (province du Shaanxi).Les résultats de l’étude mettent en évidence l’existence de deux traditions techniques distinctes entre le centre le sud de la Chine. Il existe une forte variabilité entre le matériel des deux régions, perceptible par la quasi-absence de schèmes de débitage dans le bassin de Bose et par des différences importantes de composition de l’outillage. Mais surtout, les pièces bifaciales du centre et du sud ne montrent aucune similitude structurelle, technologique ou fonctionnelle. Bien que regroupées sous une même appellation, ces pièces sont des outils différents. Sur un plan diachronique, l’existence en Chine d’industries reposant sur des schèmes de débitage et sur des schèmes de façonnage autour de 2Ma montre la possibilité d’une évolution des lignées techniques à partir d’un substrat technique local. Après 500ka, le phénomène bifacial persiste, mais n’évoluera pas vers des formes plus techniquement investies. Sur un plan spatial, une comparaison avec le matériel bifacial découvert ailleurs en Asie montre que les industries à pièces bifaciales coréennes présentent des similitudes avec les industries chinoises postérieures à 500ka. Par contre, aucun lien n’apparait avec les phénomènes bifaciaux indiens et mongols.Les industries à pièces bifaciales chinoises n’entretiennent pas de lien avec le complexe acheuléen et résultent d’un phénomène de convergence technique. Les phénomènes bifaciaux asiatiques montrent une variabilité temporelle et spatiale bien plus importante qu’habituellement envisagé. / Lately discovered Chinese biface-bearing industries are subject to opposite interpretations. Literature increasingly suggests that Chinese bifaces can be seen as a witness of diffusion from the West. The traditional model, stating a techno-cultural isolation of Asia, embodied in the “Movius Line” would thus be questioned. This assimilation of biface-bearing industries within the “Acheulian complexe” is far from achieving unanimous backing and the hypothesis of a local reinvention is also proposed. These conflicting hypotheses reveal the gaps in the methodological and conceptual frameworks used to study these industries.The chosen approach for this study aims at restoring the goals underlying the production of the tool kit through a techno-functional analysis. Chosen sites belong to a period ranging from 1Ma to 500ka : Yangwu, Gaolingpo and Nanbanshan, located in Bose basin (Guangxi Zhuang), and Lantian and Liangshan Longgangsi sites (Shaanxi province).The outcomes of this contribution bring to light the presence of a well-marked geographical discrimination between the technical traditions observed in the South on one hand and the center of mainland China on the other. A strong variability is underlined between the two areas by the virtual absence of débitage schemes in Bose basin and considerable divergence in the composition of the tool-kits. Significantly, bifacial pieces from the South and the Center show no structural, technological or functional similarities. Even though gathered under one denomination, it is clear that we are dealing with two different kinds of tools. From a diachronic perspective, the existence in China of industries relying on both débitage and shaping schemes around 2Ma indicates the possibility of bifacial technical lineage evolution from a local technical substrate. After 500ka, the bifacial phenomenon still exists but won’t evolve toward more technically invested tools. From a spatial perspective, a comparison with bifacial industries discovered elsewhere in Asia demonstrates that Korean biface-bearing industries bear similarities with Chinese industries after 500 ka. However, Chinese industries don't seem to be linked with Indian and Mongol bifacial phenomena.Chinese bifacial industries show no connexion with the Acheulian complex but rather represent a technical convergence. East-Asia bifacial phenomena involve much stronger variability through time and space than generally considered.
506

Structural and Functional Analysis of Proteins involved in Microbial Stress Tolerance and Virulence

Bangera, Mamata January 2015 (has links) (PDF)
The genus Salmonella consists of pathogenic gram negative organisms which infect intestines of birds, animals and humans. They are the causative agents of salmonellosis which is characterised by diarrhoea, nausea, fever and abdominal cramps. If not treated in time, salmonellosis can also be fatal. Salmonella genus is divided into two species Salmonella bongori and Salmonella enterica. Salmonella enterica is further divided into six subspecies out of which the subspecies enterica has many of the pathogenic serovars of this species. Salmonella typhimurium is a server in the subspecies enterica of Salmonella enterica species. Transmission of salmonellosis takes place through contaminated food and water. When the organism enters a host, it encounters a range of hostile environments such as acidic pH, lack of oxygen as well as immune response of the host. In order to establish infection, the bacterium needs to survive under stressful conditions and propagate itself. Various proteins are induced in cells under unfavourable conditions that protect them in such situations. One such group of proteins belongs to the Universal Stress Protein (USP) family. Universal Stress Proteins are a set of proteins induced in organisms when it is exposed to a variety of environmental insults including heat shock, nutrient starvation, presence of toxic compounds, etc. Although survival in adverse conditions is mediated by induction of this group of proteins, the precise mechanism of cellular protection has not been elucidated yet. The functional role of a protein is directly related to its three-dimensional structure and hence important insights can be gained regarding the role of these proteins by determining their structures. The structures of two Universal Stress Proteins from S. typhimurium; a single domain protein, YnaF and another tandem USP domain protein, YdaA were determined by X-ray crystallography and biochemical analysis was carried out on them. Guided by structure, plausible roles for both the proteins in stress tolerance of S. typhimurium have been proposed. Additionally, work was also carried out on phosphomannose isomerise from S. typhimurium. Phosphomannose isomerase is a housekeeping enzyme which catalyses the interconversion of mannose-6-phosphate and fructose-6-phosphate. Mannose is important for mannosylation of various lipids and proteins which form an important component of bacterial and fungal cell walls. Presence of a functional phosphomannose isomerise enzyme is important as it helps the organism survive adverse conditions by forming a strong cell wall which shields it from harmful environments. Moreover, phosphomannose isomerase was also found to be essential for virulence of Leishmania mexicana and Cryptococcus neoformans. The structure of phosphomannose isomerase from S. typhimurium was determined in our laboratory in the year 2009. However, in the earlier studies, the catalytically important residues had not been identified and mechanism of isomerisation was not established. Structural analysis, site directed mutagenesis and biochemical assays were used to identify key residues in the active site of StPMI. Identification of these residues might help in deciphering the catalytic mechanism which will eventually be useful to develop inhibitors that arrest the growth of Salmonella as well as other microorganisms. The work reported in this thesis describes the efforts made to enhance our understanding of functional aspects of the two Universal Stress Proteins, YnaF and YdaA and phosphomannose isomerase from S. typhimurium. Chapter 1 begins with a brief introduction to the kinds of unfavourable environments encountered by microorganisms and their strategies of adaptation. This is followed by a review of the literature on Universal Stress Proteins, which are induced in many organisms in response to arrest of or perturbations in the growth rate. Structural, biochemical and evolutionary aspects of members of the family have also been discussed. Subsequently, a brief description of the earlier work carried out on another enzyme important in stress tolerance, phosphomannose isomerase, has been documented. A detailed account of mechanisms of isomerisation carried out by aldose ketose isomerases and identification of important strategies for determination of mechanism of phosphomannose isomerase catalysed reaction have then been provided. The chapter ends with a summary of aims and objectives of the present work. Chapter 2 describes the various experimental techniques and computational methods used during the course of this thesis work. Isolation of plasmids, overexpression and purification of protein, site directed mutagenesis, biochemical assays, crystallisation of proteins, X ray diffraction data collection form a part of the experimental aspect and have been described in detail. Brief descriptions of the programs used and principles behind computational methods used for structure determination (including data processing, phasing, model building and refinement), validation and analysis have also been provided. Chapter 3 includes the structural and functional studies carried out on YdaA, a tandem USP domain protein from S. typhimurium. Expression, purification, crystallisation and structure determination of YdaA in its native and ADP bound forms are described in the chapter. Biochemical assays with radiolabelled ATP showed that YdaA was an ATPase. The crystal structure of YdaA complexed with ATP revealed the presence of ADP (hydrolysis product of ATP) only in the C-terminal domain of the protein. Based on structural analysis and presence of ATP binding motif in the C-terminal domain, it could be hypothesized that ATP hydrolysis activity of the protein is confined to the C-terminal domain of the protein. The N-terminal domain of the protein was found to play another interesting role. A zinc binding site could be identified in the N terminal domain based on structural analysis and elemental X-ray absorption studies done at the synchrotron. Site directed mutagenesis and biochemical experiments suggested that zinc binding in the N-terminal domain was not related to ATPase activity of the C-terminal domain. Additionally, an intermediate of lipid A biosynthesis pathway UDP-(3-O-(R-3-hydroxymyristoyl))-N-acetyl glucosamine was found bound to the N-terminal domain of YdaA. Lipid A is the membrane anchor of polysaccharides in the outer membrane of gram negative organisms and the intermediate occurs at the committed step of the pathway. However, no similarities could be identified between YdaA and members of the relevant biosynthetic pathway. Therefore, YdaA is unlikely to play a catalytic role in the same pathway but can function as a carrier molecule. A plausible link between the N- and C-terminal domains of YdaA could be identified by structural analysis. Many catalytically suitable residues from the N-terminal domain were found to be close to the β-phosphate of ADP bound to the C-terminal domain. Hence YdaA was identified to be a zinc binding ATPase which might play some yet unidentified role in lipid A biosynthesis pathway. Chapter 4 describes the attempts made towards understanding the functional role of YnaF, a single domain USP from S. typhimurium. A description of the expression, purification, crystallisation and X ray diffraction techniques used for structure determination of YnaF and its single site mutant have been provided in detail. Gel filtration, dynamic light scattering studies and the crystal structure determination of YnaF showed a tetrameric organisation of four USP protomers stabilised in the centre by chloride ions. Additionally, YnaF crystallised with a bound ATP even though ATP was not included in the crystallisation cocktail. Biochemical assays on YnaF with radiolabelled ATP showed that it was inactive with respect to ATP hydrolysis. When selected mutations that disrupt chloride binding were made, YnaF was converted to an active ATPase. The crystal structure of the mutant complexed with an ATP analogue revealed key differences at the active site in comparison with that of the wild type and allowed identification of residues that might be important for ATP hydrolysis in this group of proteins. Hence YnaF might play the role of a sensor protein in some signal transduction pathway involving chloride ions in bacteria. A structure based analysis and comparison of USPs from the Protein Data Bank with the structures of YnaF and YdaA is summarised at the end of this chapter. Chapter 5 describes the efforts carried out towards determination of mechanism of isomerisation catalysed by phosphomannose isomerise (PMI). Earlier reports suggest that the enzyme catalyses the reversible isomerisation of mannose-6-phosphate and fructose-6-phosphate via formation of a cis-enediol intermediate. The structure of phosphomannose isomerase from S. typhimurium has been reported by our laboratory. The enzyme is a monomer with three domains; a catalytic domain, a carboxy terminal domain and an α-helical domain. Residues from the catalytic domain were found to coordinate a zinc ion. Overexpression, purification, co crystallisation experiments and soaking studies carried out on crystals of PMI and its single site mutants are outlined in this chapter. The structure of a complex of PMI with mannose-6-phosphate at pH 7.0 revealed the presence of a blob of density close to the zinc binding site which was confirmed to be the active site by analysis of conservation of residues in the site. Based on site directed mutagenesis, activity studies and analysis of structure of PMI, zinc was identified to play an important role in maintaining the structural integrity of the active site. Electrostatic surface analysis of the structure of PMI revealed that the zinc ion might also play the role of anchoring phosphate moiety of the substrate in a highly negatively charged active site pocket. Activity assays following site directed mutagenesis studies eliminated the role of Glu264 in catalysis and implicated two lysines, Lys86 and Lys132 as the possible base in the reaction. The plausible role of a highly conserved residue Arg274 was also proposed based on comparison of structures of wild type and mutant PMIs. The future prospects of the work are briefly discussed towards the end of the thesis. Further experiments and analysis required to obtain better understanding of the functions of these proteins have been discussed. The Appendix section describes extensive crystallisation attempts that were carried out on the enzyme sorbitol-6-phosphate-dehydrogenase from S. typhimurium which catalyses the isomerisation reaction between sorbitol-6-phosphate and glucose-6-phosphate using NADPH as the cofactor. Needle shaped crystals were obtained which diffracted to a poor resolution of 7-8 Å at our in house X ray facility. Attempts to improve the quality of the crystals like co crystallisation with substrate and its analogues, soaking in various compounds and seeding are briefly described. The following manuscripts based on work described in this thesis have been published or will be communicated for publication. 1. Structural and functional analysis of two universal stress proteins YdaA and YnaF from Salmonella typhimurium: possible roles in microbial stress tolerance. Bangera M., Panigrahi R., Sagurthi S.R., Savithri H.S., Murthy M.R.N. Journal of Structural Biology, 2015 Mar; 189 (3): 238-50. 2. Structural and functional insights into phosphomannose isomerise: role of zinc and catalytic residues. Bangera M., Savithri H.S., Murthy M.R.N. Manuscript under preparation
507

Avaliação funcional de interações sociais favoráveis e desfavoráveis à inclusão de crianças em escola regular

Junqueira, Priscila Haanwinckel 27 April 2013 (has links)
Made available in DSpace on 2016-06-02T19:46:25Z (GMT). No. of bitstreams: 1 5279.pdf: 943153 bytes, checksum: c93bebc87973507d387f3b809ef7e18d (MD5) Previous issue date: 2013-04-27 / Universidade Federal de Minas Gerais / Research shows that children with visual handicap may develop isolation and other difficulties in social interactions, which may disrupt the process of inclusion in school. The theoretical and practical field of social skills shows that such interactions can be classified as pro- and noninclusive behaviors. Also, the frequency of such behaviors depend on the interactions (or lack thereof) between teacher and student, which are usually established by the teacher. There is currently a lack of observational studies in social skills and social competence. Thus, it is important to examine the social interaction of blind children in the school environment -- in particular using direct observation, since this method provides important data to perform a functional evaluation of pro- and noninclusive behaviors that will identify conditions that are both favorable and unfavorable to the process of inclusion. Direct observation was complemented by reports from parents and teachers, as well as self-reports and sociometric evaluations. This study aimed to: (1) Functionally describe the pro- and noninclusive social performances of two blind children in interaction with their peers and teachers in terms of antecedents and consequences; (2) Define, through measuring scales: the social skills repertoire, behavior problems, academic competence, and the sociometric status of included children; (3) Link pro- and noninclusive behaviors to social skills indicators, behavior problems, and sociometric status of children. The study participants were two children, a boy and a girl, both nine years old and diagnosed with congenital blindness. Participants were enrolled in public, regular education schools, and were filmed in the classroom environment during Portuguese classes and free activities suggested by the researcher. The observed performances were described in terms of antecedents, responses and consequences, and the percentage of correlation between the responses and events was identified. The Social Skills Evaluation System (SSRS-BR) was used with parents and teachers, as well as with the children, to obtain information on the children's behaviors. Furthermore, the children's classmates underwent a sociometric evaluation. The analysis of data collected through direct observation of behavior indicates that around 70% of performances emitted in classroom interactions were classified as proinclusive. This information is contradictory when compared to data from SSRS-BR and from sociometric evaluation. In general, the observed children were socially competent in their social interactions at school, which does not guarantee their full inclusion in this environment. / Pesquisas apontam que crianças com deficiência visual podem apresentar isolamento e outras dificuldades de interação social que comprometem o processo de inclusão escolar. O campo teórico-prático das habilidades sociais mostra que estas podem ser caracterizadas como comportamentos pró-inclusivos ou anti-inclusivos e que a frequência de ambos depende das condições interativas de ensino, em geral dispostas pelo professor. A literatura aponta para uma carência de estudos de observação em habilidades sociais e competência social. Desta forma, é importante estudar a interação social das crianças cegas no ambiente escolar, principalmente por meio de observação direta, pois este método provê informações importantes para se efetuar uma avaliação funcional dos comportamentos pró e anti-inclusivos identificando possíveis condições favoráveis ou desfavoráveis ao processo de inclusão. A observação direta foi complementada por dados de relato obtidos com diferentes pessoas (pais, professores), auto-relato e avaliação sociométrica (colegas). Este estudo teve como objetivos: (1) Descrever funcionalmente os desempenhos sociais pró e anti-inclusivos de duas crianças cegas em interação com seus colegas e professores, em termos de seus antecedentes e consequentes; (2) Caracterizar por meio de escalas de medidas, o repertório de habilidades sociais, os problemas de comportamento, a competência acadêmica e o status sociométrico das crianças incluídas; (3) Relacionar os comportamentos pró e anti-inclusivos aos indicadores de habilidades sociais, problemas de comportamento e status sociométrico das crianças. A pesquisa foi realizada com duas crianças, ambas com nove anos de idade (um menino e uma menina), diagnosticadas com cegueira congênita e matriculadas em escolas públicas da rede regular de ensino. Utilizou-se o recurso de filmagem no ambiente da sala de aula (aulas de português e atividade livre proposta pela pesquisadora). Os desempenhos observados foram descritos, em termos de antecedentes, respostas e consequentes, identificando-se a percentagem de correlação entre as respostas e os eventos. Para a avaliação via escalas, foi utilizado o Sistema de Avaliação de Habilidades Sociais (SSRS-BR), obtendo informações sobre os comportamentos das crianças por meio dos pais, professores e auto-relato. Além disso, foi realizada avaliação sociométrica pelos colegas de sala das crianças. A análise dos dados coletados com observação direta do comportamento indica que a maior parte, cerca de 70%, dos desempenhos emitidos em interação na sala de aula foram classificados como pró-inclusivos. Esse dado, quando comparado aos resultados do SSRS-BR e avaliação sociométrica, apresenta contradições, com a avaliação das professoras e concordância com a avaliação pelos pares. De maneira geral, as crianças observadas conseguem ser socialmente competentes nas suas interações sociais na escola, o que não garante a sua total inclusão nesse ambiente.
508

A reinervação do músculo extensor longo dos dedos (EDL) de ratos (rattus norvegicus) seria influenciada pelo uso do laser de baixa potência e do tecido adiposo na técnica de tubulização? / The reinnervation of extensor digitorius longus (EDL) of rats (Rattus norvegicus), would be influenciate by the association of adipose tissue and low power laser in tubulization technique by vein?

Luis Henrique Rapucci Moraes 27 November 2009 (has links)
Lesões nervosas periféricas com alterações morfofuncionais são de grande importância clínica, porque pode prejudicar a função, comprometendo a sensibilidade e/ou a motricidade do órgão alvo. Quando o nervo é lesado, o indivíduo torna-se impossibilitado de realizar suas atividades, seja profissional ou pessoal, e a partir do acidente esta situação se agrava ainda mais, pois tem início uma trajetória de sofrimento e humilhações decorrentes do tipo de assistência que passa a receber, tendo em vista, ainda, a fragilidade emocional e o abatimento moral de que passa a ser vítima. Na tentativa de reparo de lesões graves de nervos periféricos, várias técnicas têm sido utilizada, mas algumas com prejuízos funcionais para outras área do corpo, como por exemplo, quando se usa outro nervo no enxerto. Considerando que enxertos venosos tem tido bons resultados na capacidade regenerativa das fibras nervosas, e como elas são encontradas em abundância e em locais de fácil acesso cirúrgico, pensou-se em verificar se o tecido adiposo e o laser de baixa potência alterariam os resultados da reinervação, por tubulização, em músculos de contração rápida (EDL). Para isso foi utilizado 84 ratos (Rattus norvegicus) da linhagem wistar, machos, que foram divididos em 12 grupos (oito experimentais e quatro controles). Nos grupos experimentais (GE) foi utilizada tubulização de veia preenchida, ou não de tecido adiposo (GEVV e GEVG, respectivamente), com e sem tratamento de laser (GEVVL e GEVGL, respectivamente). Os grupos controles (GC) receberam os nomes de positivos (GCP) quando os animais não sofreram intervenção cirúrgica, e negativos (GCN) quando os animais foram submetidos à desnervação do nervo ciático. Todos os grupos tiveram os seus animais sacrificados em dois períodos, 45 e 150 dias, após o início do experimento. A certificação da recuperação foi feita por meio da análise dos músculos inervados por ele (EDL), comparando-os com os respectivos grupos controles. Técnicas de microscopia, Imunofluorescência (MyoD e miogenina), apoptose (Tunel), morfométricas e análise funcional do ciático, foram empregadas nesta investigação. Os resultados mostraram que aos 45 dias pós desnervação os dados dos grupos experimentais estavam mais próximos do grupo controle negativo, mas aos 150 dias eles estavam mais próximos aos do grupo controle positivo. Baseado nos dados obtidos pode-se concluir que o uso de tecido adiposo e do laser de baixa potência na técnica de tubulização do nervo ciático interferem na recuperação do músculo EDL desnervado. / The peripheral nerves injuries with morphofunctional alterations, have great clinical importance because could prejudice the function, committing the sensibility and/or the motricity of target organ. When nerve is damage, the individual becomes disabled to realize yours activities, either professional or personal, in the post accident periods, this situation aggravates each more, therefore initiate a trajectory of suffering and distressing despite of the kind of assistance that this person receives, in view of your emotional fragility and your moral discouragement that pass to be victim. In attempt to repair severe peripheral nerves lesions, many techniques had been used, but some present functional prejudices to other area of bodies, for example when other autologous nerve graft it is used. Considering that, vein graft had demonstrated good results in regenerative nerve fibers capacity, and the vein are found in abundance in many locals of chirurgic access, it thought in verify if the adipose tissue and low power laser could alter the reinnervation results, by tubulization technique, in fast twitch muscle (EDL). For this, was used 84 rats (Rattus norvegicus) wistar, male, divided in 12 groups (eight experimental and four controls). In the experimental groups (EG) was used tubulization by vein combined / or not with adipose tissue (EGV and EGVA, receptively), with or without laser treatment (EGVL and EGVAL, respectively). The controls groups (CG) was called of positives (CGP) when the animals did not subject to transaction nerve, and negatives (CGN) when the sciatic nerve was transaction in this animals. All groups had the animals scarified in two periods, 45 and 150 days post experiments beginning. The recuperation was notified by means of muscle innervated analysis (EDL), comparing with the respective controls groups. Microscope techniques, Immunofluorescence for (MyoD and Miogenin), apoptosis by (Tunel assay), morphometrics and sciatic functional analysis, were employed in this investigation. The results showed that in the 45 days post-dennervation, the data of experimental groups was nearest of negative control group (transaction sciatic nerve), but in the 150 days they was nearest to the positive control group. Based on this, could be conclude that the use of adipose tissue and low power laser used in the tubulization technique by vein in the sciatic nerve interfere in the recuperation of EDL muscle dennervated.
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Multiplicidade de soluções para equação de quarta ordem / Multiplicity of solutions for fourth order equation

Monteiro, Evandro, 1982- 10 April 2011 (has links)
Orientador: Djairo Guedes de Figueiredo / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-18T23:11:17Z (GMT). No. of bitstreams: 1 Monteiro_Evandro_D.pdf: 681089 bytes, checksum: 5ec4729a2d7b386329193adf424f6b42 (MD5) Previous issue date: 2011 / Resumo: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital / Abstract: The complete abstract is available with the full electronic digital thesis or dissertations / Doutorado / Matematica / Doutor em Matemática
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Exploration de la biodiversité bactérienne dans un sol pollué par les hydrocarbures : analyse par marquage isotopique du potentiel métabolique et de la dynamique des communautés impliquées dans la dégradation / Bacterial diversity exploration in hydrocarbon polluted soil : metabolic potential and degrader community evolution revealed by isotope labeling

Martin, Florence 13 October 2011 (has links)
Les hydrocarbures aromatiques polycycliques (HAP) sont des composés ubiquitaires issus de la combustion incomplète de matières organiques. Ils sont à l'origine de pollutions de l'environnement, surtout liées à l'exploitation des produits pétroliers, car ce sont des composés toxiques pour les êtres vivants et pour l'homme en particulier. De nombreuses bactéries capables de dégrader les HAP ont été isolées et étudiées, mais celles qui les dégradent in situ sont mal connues, car moins de 5% des bactéries du sol sont cultivables en laboratoire. Le premier objectif de cette étude était d'identifier les bactéries qui dégradent les HAP dans le sol par des méthodes moléculaires indépendantes de la culture. A cette fin, une stratégie de marquage isotopique in situ a été mise en œuvre qui repose sur l'utilisation du phénanthrène, un HAP à trois cycles, dans lequel l'isotope naturel du carbone a été remplacé par le 13C. Cette molécule a été introduite comme traceur dans des microcosmes contenant du sol provenant d'un bassin de rétention des eaux de ruissellement d'autoroute. Les bactéries ayant incorporé le 13C ont ensuite été identifiées par séquençage des gènes d'ARNr 16S amplifiés à partir de l'ADN marqué extrait du sol. Les résultats montrent que des Betaprotéobactéries peu étudiées à ce jour, appartenant aux genres Acidovorax, Rhodoferax, Hydrogenophaga et Thiobacillus, ainsi que des Rhodocyclaceae, étaient les principaux acteurs de la dégradation du phénanthrène. La prépondérance des Betaprotéobactéries a été établie par des mesures de PCR quantitative. Une analyse dynamique de la diversité bactérienne a montré que celle-ci changeait en fonction de la biodisponibilité du phénanthrène. En outre, la diversité d'arène-dioxygénases impliquées dans la dégradation des HAP a été explorée sur le plan phylogénétique et fonctionnel. Nous avons ainsi détecté des séquences nouvelles, pour la plupart apparentées à des dioxygénases de Sphingomonadales et de Burkholderiales. Grâce à la construction et l'expression d'enzymes hybrides, il a été possible, pour la première fois, d'associer une activité catalytique d'oxydation des HAP à des séquences partielles de gènes, amplifiées à partir de l'ADN du sol. Les résultats obtenus et les outils mis au point dans cette étude pourront servir à développer des méthodes de diagnostic et de suivi de biodégradation de polluants, par exemple dans le cadre d'opérations de bioremédiation de sites pollués par les HAP. / Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous compounds produced by incomplete combustion of organic matter. They are a source of environmental pollution, especially associated to oil product exploitation, and represent a threat for living organisms including human beings because of their toxicity. Many bacteria capable of degrading PAHs have been isolated and studied. However, since less than 5% of soil bacteria can be cultivated in the laboratory, bacterial species able to degrade PAHs in situ have been poorly studied. The first goal of this study was to identify bacteria that degrade PAHs in soil using culture-independent molecular methods. To this end, a strategy known a stable isotope probing has been implemented based on the use of phenanthrene, a three rings PAH, in which the natural isotope of carbon was replaced by 13C. This molecule has been introduced as a tracer in microcosms containing soil from a constructed wetlands collecting contaminated water from highway runoff. Bacteria having incorporated the 13C were then identified by 16S rRNA gene sequence analysis after PCR amplification from labeled genomic DNA extracted from soil. The results show that so far little studied Betaproteobacteria, belonging to the genera Acidovorax, Rhodoferax, Hydrogenophaga and Thiobacillus, as well as Rhodocyclaceae, were the key players in phenanthrene degradation. Predominance of Betaprotéobactéries was established thanks to quantitative PCR measurements. A dynamic analysis of bacterial diversity also showed that the community structure of degraders depended on phenanthrene bioavailability. In addition, the phylogenetic diversity of ring-hydroxylating dioxygenases, enzymes involved in the first step of PAH degradation, has been explored. We detected new sequences, mostly related to dioxygenases from Sphingomonadales and Burkholderiales. For the first time, we were able to associate a catalytic activity for oxidation of PAHs to partial gene sequences amplified from soil DNA, by constructing hybrid enzymes and assaying their activity The results obtained and the tools implemented in this study may be used to develop methods for the diagnostic and monitoring of pollutant biodegradation in processes such as bioremediation of PAHs contaminated sites.

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