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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.
101

Trois figures de détective à Hollywood : Sam Spade, Nick Charles et Dashiell Hammett - les enjeux du genre dans la construction du personnage / Three detective characters in Hollywood : Sam Spade, Nick Charles and Dashiell Hammett - film genre at stake

Ananian, Francine 19 January 2018 (has links)
Le Faucon maltais et L’Introuvable de Dashiell Hammett ont été portés avec succès au cinéma, faisant apparaître le personnage typiquement américain du détective privé avec les figures de Sam Spade et de Nick Charles.La dernière incarnation de Sam Spade, sous les traits de Humphrey Bogart dans le film de John Huston, en 1941, demeure l’une des figures les plus célèbres du film noir. Nick Charles, sous les traits de William Powell dans le film de Woody S. Van Dyke, en 1934, fut si populaire que l’acteur et le personnage, échappant à son auteur, furent exploités dans une suite de cinq films. Pourquoi le public français ne connaît-il guère que les premiers (personnage et acteur) et méconnaît-il les seconds ?Quelle place dans cette concurrence tient la figure de Dashiell Hammett, détective puis écrivain, devenu un personnage d’écrivain-détective dans Hammett, un film de Wim Wenders en 1982 ?L’examen de toutes les adaptations des romans de l’auteur, de 1931 à 1942, permet de comparer les diverses représentations de ses figures littéraires d’enquêteur. Celui des cinq films qui, de 1934 à 1947, ont repris le personnage de Nick Charles, montre la difficulté à conserver une cohérence au personnage.L’observation du changement du goût du public, de la Grande Dépression à l’après-Seconde Guerre Mondiale, et celle de l’évolution de la carrière d’Humphrey Bogart et de William Powell, permet de comprendre pourquoi le public français, si attaché à la notion de film noir, n’a retenu que le premier. Enfin, la constatation de l’intérêt éditorial, renouvelé en France au début du vingt-et-unième siècle, pour toute l’œuvre et la vie de Dashiell Hammett, conduit à considérer, temporairement peut-être, la figure de l’auteur comme un mythe moderne. / The Maltese Falcon and The Thin Man by Dashiell Hammett, adapted successfully to the screen, revealed the typically American character of the private detective, with Sam Spade and Nick Charles.The last incarnation of Sam Spade by Humphrey Bogart in 1941 John Huston’s movie remains one of the most famous film noir figures. Nick Charles, with William Powell in Woody S. Van Dyke’s film in 1934, was so popular that both the character, escaping his creator, and the actor were reused in a succession of five films, until 1947.Why does the contemporary French public only know the first (character and actor) and why does it almost ignore the second ?Between them, what place does Dashiell Hammett hold, detective then writer, who became a character of detective writer in Hollywood Wim Wenders’s movie Hammett in 1982 ?The study of all Dashiell Hammett novels adaptations, from 1931 to 1942, enables to compare the various representations of his investigator characters. The study of the five movies reusing Nick Charles character allows to follow its lack of coherence.The observation of the change of the public taste, from the Great Depression until the post- Second World War years and the examination of the cinematographic careers of the two actors, explain the Bogart’s fame in France.Eventually, the French editorial revival of Dashiell Hammett at the beginning of the 21st century makes it possible to consider the author figure as a new myth.
102

Mapeamento de QTL para características de interesse industrial da madeira de Eucalyptus em progênie de híbridos interespecíficos / Genetic mapping of QTL for characteristics of industrial interest of the Eucalyptus’s wood in an interspecific hybrid progeny

Macedo , Luciano Medina 26 February 2009 (has links)
Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-21T11:32:31Z No. of bitstreams: 2 Dissertação - Luciano Medina Macedo - 2009.pdf: 2515834 bytes, checksum: e30a9d4d1538ea85e265eedf8a8e2396 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-09-21T11:32:53Z (GMT) No. of bitstreams: 2 Dissertação - Luciano Medina Macedo - 2009.pdf: 2515834 bytes, checksum: e30a9d4d1538ea85e265eedf8a8e2396 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2016-09-21T11:32:53Z (GMT). No. of bitstreams: 2 Dissertação - Luciano Medina Macedo - 2009.pdf: 2515834 bytes, checksum: e30a9d4d1538ea85e265eedf8a8e2396 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2009-02-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work a genetic map and QTL mapping were built for growth and wood quality characters in a interspecific hybrids progeny of Eucalyptus. Samples of genomic DNA were isolated from 200 individuals belonging to a interspecific hybrids progeny. A screening of 300 pairs microsatellite loci (SSR) primers was done and from those 76 loci were selected to compose 19 tetraplex combinations, based in presence of valid polimorfism for QTL mapping and in quality of allele’s amplification. Among the 76 loci appraised in multiplex system, 14 presented significant distortion of segregation in χ2 test using "Criterion of Bonferroni" with 5% of significance, and they were excluded of mapping analyses. Using LOD 3 and recombination fraction of 0.40, 12 linkage groups compatible with described in other mapping works in Eucalyptus were identified. An integrated genetic map was obtained with total length of 1240 cM and medium distance among marks of 22 cM, It provides a covering genomic of approximately 75% in relation to genome size of Eucalyptus gender. A part of density appraised by pilodyn apparatus, all others characters showed QTL association through variance analysis (single marks analysis). For growth characters, four loci were associated to seven QTL and 19% for genotypic variation of diameter, 18% for height and 10% for volume these QTL were capable to explain. Among wood quality characters evaluated by NIRS, three QTL were capable to explain 17% of genotypic variance for density, while for yield cellulose, four QTL together were capable to explain 7,5% of this variance. For the characters related with lignin properties also evaluated by NIRS, were identified three QTL capable to explain 9% of genotypic variation for lignin quantity, and two QTL were capable to explain 6% of genotypic variation for siringil/guaiacil relationship. Most of identified QTL for different characters appraised in this work coincided with linkage groups and as well the amount of variance of QTL detected by other authors, which carried out QTL mapping for these same characters. Although comparatively the SAM showed inferior efficiency in relation to fenotypic selection, it can be useful for optimization of futures field experiments into progenies which QTL mapping already was accomplished, where only best genotypes can be stablished in field instead to whole progeny. The application of SAM in forest breeding programs is possible to be used in early selection starting from second breeding generation, using QTL information of crosses mapped in these breeding programs. However, QTL used for SAM should be robust in progenies where they were mapped, like as QTL identified in linkage group 9 for character DAP in this dissertation, that beside consistence datas in progeny DG x GL2, were capable to explain the same amount of variability for QTL mapped by Kirst et al. (2007) (12%), which used different genetic markers and techniques for QTL mapping. These results prove that application of SAM is viable in breeding programs, and apart of peculiarities in each crossing, certain linkage groups are stable among different progenies for a same character. / Neste trabalho foi construído um mapa genético e realizado o mapeamento de QTL para caracteres de crescimento e qualidade da madeira em uma progênie de híbridos interespecíficos de Eucalyptus. Foram isoladas amostras de DNA genômico de 200 indivíduos pertencentes a uma progênie de híbridos interespecíficos. A partir de 300 pares de primers microssatélites (SSR), foram selecionados com base na presença de polimorfismo válido para o mapeamento de QTL e na qualidade de amplificação de seus alelos, 76 locos para compor 19 combinações tetraplex. Dentre os 76 locos avaliados em sistema multiplex, 14 apresentaram distorção de segregação significativa no teste χ2 perante o “Critério de Bonferroni” com nível de significância de 5% e foram excluídos das análises de mapeamento. Utilizando LOD 3 e fração de recombinação de 0,40, foram identificados 12 grupos de ligação compatíveis com os descritos em outros trabalhos de mapeamento em Eucalyptus. Foi obtido um mapa genético integrado com comprimento total de 1240 cM e distância média entre marcas de 22 cM, que proporciona uma cobertura genômica de aproximadamente 75% em relação ao tamanho do genoma deste gênero. Com exceção da densidade avaliada por pilodyn, todos os outros caracteres avaliados apresentaram associação a QTL por análise de variância (análise de marcas simples). Para os caracteres de crescimento, quatro locos estiveram associados a sete QTL, sendo que o montante da variação genotípica que estes QTL foram capazes de explicar foi de 19% para diâmetro, 18% para altura e 10% para volume. Dentre os caracteres de qualidade da madeira avaliados por NIRS, três QTL foram capazes de explicar 17% da variância genotípica para densidade, enquanto para o rendimento de celulose quatro QTL foram capazes de explicar juntos 7,5% desta variância. Para os caracteres relacionados com as propriedades da lignina também avaliados por NIRS, foram identificados três QTL capazes de explicar 9% da variação genotípica do caráter teor de lignina, e dois QTL capazes de explicar 6% da variação genotípica para a relação siringil/guaiacil. A maioria dos QTL identificados para os diferentes caracteres avaliados neste trabalho coincidiram com os grupos de ligação e o montante da variância representada com QTL identificados nos trabalhos de outros autores que realizaram mapeamento de QTL para os mesmos caracteres avaliados. Embora comparativamente a seleção assistida por marcadores moleculares tenha apresentado eficiência inferior em relação à seleção fenotípica, ela pode ser muito útil na otimização de futuros experimentos de campo de progênies para as quais já foi realizado o mapeamento de QTL, onde somente os genótipos com desempenho superior poderão ser avaliados em campo ao invés de toda a progênie. A aplicação de SAM em programas de melhoramento genético florestal é possível para a seleção precoce a partir da segunda geração de melhoramento, sempre que forem utilizadas informações de QTL mapeados nos cruzamentos realizados por estes programas de melhoramento. No entanto, estes QTL que serão utilizados para SAM, devem ser robustos nas progênies onde eles foram mapeados, tal como os QTL identificados nesta dissertação no grupo de ligação 9 para o caráter DAP, que além da consistência dos dados da progênie DG x GL2, foram capaz de explicar o mesmo montante da variabilidade com QTL mapeados para este caráter (12%) por Kirst et al. (2007), que utilizaram diferentes marcadores genéticos e técnicas de mapeamento de QTL. Estes dados comprovam que a aplicação da SAM é viável em programas de melhoramento, e que apesar das peculiaridades únicas de cada cruzamento, determinados grupos de ligação apresentam estabilidade de QTL entre diferente progênies para um mesmo caráter.
103

L’adhésion bactérienne sondée à l’échelle moléculaire / Bacterial adhesion probed at the molecular level

Bulard, Emilie 19 October 2012 (has links)
Les matériaux en contact avec des fluides biologiques peuvent être colonisés par de nombreux microorganismes (bactéries, levures…) et des macromolécules telles que les protéines. Lorsqu’il s’agit de bactéries pathogènes, l’adhésion bactérienne devient un problème, en particulier dans les milieux agroalimentaire et biomédical, car elle se poursuit jusqu’à la formation de biofilms bactériens, des bio-structures plus résistantes à l’action des antibiotiques que les bactéries isolées. Malgré une littérature abondante sur les processus d’adhésion bactérienne, l’interface surface – bactérie est encore mal comprise principalement à cause du manque de caractérisation à l’échelle moléculaire. Dans ce travail, nous utilisons une technique d’optique non linéaire du second ordre, la spectroscopie vibrationnelle de Génération de Fréquence Somme (SFG) à large bande, pour sonder spécifiquement des interfaces ordonnées à l’échelle moléculaire. Le principe consiste à envoyer un faisceau picoseconde visible et un faisceau femtoseconde infrarouge (accordé aux longueurs d’onde des vibrations des molécules de la surface) sur le substrat en contact avec des biomolécules en milieu aqueux. L’optimisation de la déconvolution et la modélisation du spectre SFG expérimental, réalisées dans le cadre de travail, permettent d’obtenir quantitativement la conformation des molécules de la surface du substrat. Nous nous sommes intéressés à la colonisation d’une surface structurée en « brosse » composée de monocouches autoassemblées (SAM) hydrophobes d’OctaDécaneThiol (ODT) par des bactéries Lactococcus lactis. Afin de reproduire les conditions naturelles de la colonisation bactérienne, nous avons aussi étudié le rôle de la présence de protéines, en l’occurrence l’albumine de sérum bovin. L’étude par spectroscopie SFG couplée avec des mesures de microscopie confocale de fluorescence a permis de proposer un mécanisme de l’adhésion bactérienne sur la SAM d’ODT, qui dépend de la présence des protéines. Nous avons démontré que les bactéries seules en suspension avaient un impact sur la conformation du support pouvant conduire à une augmentation ou à une diminution de la colonisation bactérienne selon le caractère hydrophobe / hydrophile de la paroi bactérienne. La présence des protéines avant ou pendant la colonisation bactérienne conduit à de nouveaux changements structuraux de la SAM d’ODT et à une importante diminution de l’adhésion bactérienne et du biofilm résultant (indépendamment du caractère hydrophobe / hydrophile de la paroi bactérienne). Cette étude démontre d’une part la faisabilité et l’intérêt de la spectroscopie vibrationnelle SFG pour l’étude de l’adhésion bactérienne in situ, et d’autre part que l’effet des bactéries et des protéines sur la conformation des surfaces est à prendre en compte lors de l’ingénierie de nouveaux matériaux à effet antiadhésif et/ou bactéricide. / Materials exposed to a fluid can be contaminated by microorganisms and macromolecules such as proteins. In food industry or biomedicine, surface colonization by pathogenic bacteria is harmful because it leads to biofilm formation, a microbial consortium more resistant to antiobiotics than planktonic bacteria. Despite of an abundant literature on bacterial adhesion, bacteria-surface interactions still require more studies, in particular at the molecular level. In this work, Broad Band Sum Frequency Generation (BBSFG) spectroscopy was employed to investigate specifically well-ordered interfaces at the molecular level. BBSFG consists in overlapping in time and in space a picosecond visible beam and a femtosecond infrared beam onto the sample in contact with bacteria in water. The IR beam is tuned to the wavelength range of suitable vibrational transitions of adsorbed molecules. Optimisation of the deconvolution procedure of SFG spectra and modeling were performed to derive quantitatively the molecular conformational changes of the interface in response to bacterial adhesion. We have studied the colonization of a well-defined “brush” surface composed of hydrophobic OctaDecaneThiols (ODT) Self-Assembled Monolayer (SAM) by Lactococcus lactis bacteria. In order to mimic natural conditions of bacterial adhesion, where bacteria and proteins coexist, we have also studied the role of Bovin Serum Albumin (BSA) proteins. SFG data and fluorescence confocal microscopy measurements led us to propose a mechanism of bacterial adhesion onto the ODT SAM which depends on the presence of BSA. We have demonstrated that adhesion of bacteria in distilled water induces measurable effects on the ODT SAM conformation and on the bacterial adhesion strength, depending on the hydrophobic / hydrophilic character of the bacterial cell wall. Different behaviors of the ODT were observed when BSA proteins were present before or during bacterial colonization. In particular, BSA leads to a marked antimicrobial effect (independent of the hydrophobic / hydrophilic character of the bacterial surface). This study demonstrates the potential of BBSFG to study in situ bacterial adhesion. It also shows that the modification of surface properties by bacterial adhesion must be taken into account for the design of materials suitable to control or eradicate biofilm formation.
104

Caractérisation d'un nouveau RiPP issu du microbiote intestinal : la Ruminococcin C / Characterization of a new RiPP derived from the intestinal microbiota : Ruminococcin C

Balty, Clémence 21 November 2019 (has links)
Le microbiote humain est constitué de milliers d’espèces bactériennes qui synthétisent de nombreux métabolites secondaires. Cependant, notre connaissance des produits naturels dérivés du microbiome est encore limitée. Parmi eux, les RiPPs (Ribosomally Synthesized and Post-translationally modified Peptides) apparaissent comme une famille majeure de produits naturels possédant diverses structures et fonctions biologiques dont des propriétés antibiotiques, en faisant une famille de molécules d’intérêt majeur pour la santé publique. La biosynthèse des RiPPs commence par la traduction d’un peptide précurseur, qui est ensuite maturé par l’action d’une ou plusieurs enzymes avant l’excision d’une séquence signal et l’export du produit naturel actif. La diversité structurale et fonctionnelle des RiPPs démontre la nécessité de la compréhension des voies de biosynthèse de ces produits naturels, de l’étude systématique des mécanismes de modification et de la caractérisation des maturases associées. En particulier, une famille de métallo-enzymes, les enzymes à radical S-adénosyl-L-méthionine (SAM), a récemment été impliquée dans la biosynthèse de nombreux RiPPs. Ces enzymes catalysent un large éventail de réaction, via un mécanisme de chimie radicalaire, aboutissant à une grande variété de modifications post-traductionnelles. Néanmoins, les voies de biosynthèse de nombreux RiPP restent mal comprises.En 2011, il a été montré que Ruminococcus gnavus, un membre important du microbiote humain, produisait un peptide actif contre Clostridium perfringens, la Ruminococcin C (RumC). Le séquençage de l’opéron de biosynthèse de RumC montre la présence de cinq gènes codants des peptides précurseurs (RumC1-5) et deux gènes codant des enzymes (RumMC1 et RumMC2).L’objectif de ma thèse est de mieux comprendre les voies de biosynthèse des produits naturels au sein du microbiome humain. Nous avons démontré l’appartenance des protéines RumMC1 et RumMC2 à la famille des enzymes à radical SAM, ainsi que leurs implications dans la formation de quatre modifications post-traductionnelles (ponts α-thioether) essentielles à l’activité antibiotique de RumC1 et RumC2. Ces études nous ont permis de proposer un mécanisme catalytique pour la maturation de la Rummonicoccin C et ainsi de mieux documenter cette famille d’enzymes émergentes. / The human microbiota consists of thousands bacterial species which synthesize numerous secondary metabolites. However, our knowledge of microbiome-derived natural products is still limited. Among them, RiPPs (Ribosomally synthesized and Post-translationally modified Peptides) are emerging as a major family of natural products possessing diverse structures and biological functions including antibiotic properties, making them a major family of molecules of interest for public health. The biosynthesis of RiPPs occurred by the translation of a precursor peptide, which is then matured via the action of one or more enzymes before the excision of a signal sequence and the export of the active natural product. The structural and functional diversity of RiPPs demonstrates the need for understanding the biosynthetic pathways of these natural products, the systematic study of the modification mechanisms and the characterization of associated maturases. In particular, a family of metallo-enzymes, the S-adenosyl-L-methionine radical (SAM) enzymes, has recently been implicated in the biosynthesis of many RiPPs. These enzymes catalyze a wide range of reactions, via a mechanism of radical chemistry, resulting in a wide variety of post-translational modifications. Nevertheless, the biosynthetic pathways of many RiPPs remain poorly understood.In 2011, it was shown that Ruminococcus gnavus, a major member of the human microbiota, produced an active peptide against Clostridium perfringens, Ruminococcin C (RumC). Sequencing of the RumC biosynthesis operon shows the presence of five genes encoding precursor peptides (RumC1-5) and two genes encoding enzymes (RumMC1 and RumMC2).The aim of my thesis is to understand the biosynthetic pathways of natural products within the human microbiome. We have demonstrated that the RumMC1 and RumMC2 proteins belong to the radial SAM enzyme family, as well as their involvement in the formation of four post-translational modifications (α-thiother bridges) essential for the antibiotic activity of RumC1 and RumC2. These studies allowed us to propose a catalytic mechanism for the maturation of Rummonicoccin and thus to better document this family of emerging enzymes.
105

Jag tänker att inkludering kanske inte ser likadan ut för alla barn : En kvalitativ intervjustudie om barns inkludering

Poltorak, Monika, Sliwonik, Sandra January 2024 (has links)
Syftet med denna studie har varit att undersöka hur förskollärare samtalar om och tillämpar sitt arbetssätt för inkludering av barn i behov av särskilt stöd. Studien har utförts genom semistrukturerade intervjuer av verksamma förskollärare på fem olika förskolor i Stockholm. Vårt resultat visar grundläggande översikt av förskollärarnas uppfattningar om inkludering. Resultaten och analysen av intervjuerna visade även på att inkludering uppfattas som en positiv ställning mellan förskollärarna, dock kan detta föra med sig en del problematik i praktiken. Resultaten framför tydligt att alla barn oavsett förutsättningar och behov ska ha rätt till inkludering i förskolan oberoende av vilka funktionsvariationer eller svårigheter barnet har. Ytterligare förekommer det även att i inkluderingsarbetet är anpassning en av de viktigaste ståndpunkterna och ska tillämpas för alla barn och dess behov. Resurser bör inte tilldelas lika mycket utan fördelas utifrån varje enskilda barnets behov. Det är viktigt att ha närvarande, kompetenta och engagerade förskollärare som kan skapa meningsfulla sammanhang där barnen kan känna tillhörighet i gruppen. Resultaten visar på att mindre grupper gynnar alla barn. Förskollärarnas svar sammanfaller med den tidigare forskningen där deras svar visar tydligt även på att större barngrupper och brist av resurser är ett hinder i inkluderingsarbetet. Kunskapen samt det pedagogiska förhållningssättet är väsentliga delar i arbetet för att kunna möta alla barns behov och svårigheter.
106

Caractérisation de nouvelles enzymes impliquées dans la biosynthèse de cofacteurs de microorganismes. Mécanismes des tyrosine lyases à radical SAM / Characterization of novel enzymes involved in biosynthesis of microbial cofactors. Mechanisms of radical SAM tyrosine lyases

Decamps, Laure 13 January 2014 (has links)
Le cofacteur F420 est un coenzyme d’oxydoréduction essentiel pour la méthanogenèse chez les archées, un processus qui influence fortement les interactions métaboliques au sein du microbiote intestinal ; en outre, il joue un rôle important dans la pathogénicité de la bactérie Mycobacterium tuberculosis. L’étude de sa biosynthèse présente donc un intérêt majeur en Biologie.La formation du chromophore du F420 est catalysée par la F0-synthase, qui contient, de façon unique, deux domaines caractéristiques des enzymes à radical SAM (rSAM). Ces enzymes catalysent le clivage de la S-adénosylméthionine (SAM) pour former un radical 5′ déoxyadénosyle, capable d’initier un grand nombre de réactions radicalaires.Nous avons réussi à identifier les substrats de la F0-synthase et à reconstituer la synthèse du F0 in vitro. Nous avons également démontré que cette enzyme contient deux centre [4Fe-4S] 2+/1+ rSAM fonctionnels et caractérisé les étapes de la synthèse du F0. Ceci nous a permis de proposer un mécanisme réactionnel pour la F0 synthase. Nous avons ensuite entrepris la comparaison de la F0 synthase avec les deux autres enzymes rSAM tyrosine lyases connues à ce jour : ThiH, impliquée dans la biosynthèse de la vitamine B1, et HydG, impliquée dans la biosynthèse du cofacteur métallique de l’hydrogénase à fer-fer. Nous avons ainsi découvert de nouveaux aspects de la réaction de clivage de la tyrosine par ces enzymes, permettant une meilleure compréhension de ce groupe émergent au sein de la superfamille des enzymes rSAM. / Cofactor F420 is a redox coenzyme crucial for methanogenesis in Archaea, a process which plays a major role in metabolic interactions in the gut microbiota ; It also constitutes a key pathogenicity factor for Mycobacterium tuberculosis. Understanding the biosynthesis of this cofactor is thus of major interest.The biosynthesis of the chromophore of F420 is catalyzed by F0 synthase, which comprises, in a unique manner, two radical SAM (rSAM) domains. These enzymes catalyze the cleavage of S adenosylmethionine (SAM) to produce a 5′-deoxyadenosyl radical, which can initiate a broad range of radical reactions.We succeeded to identify the substrates of F0-synthase and to perform the biosynthesis of F0 in vitro. We ascertained that F0-synthase contains two functional [4Fe-4S]2+/1+ rSAM clusters, and characterized the steps of the reaction of F0 synthesis. Based on these date, we proposed a mechanism for the F0-synthase reaction. Furthermore, we compared F0 synthase with the two other radical SAM tyrosine lyases identified to date: ThiH, which is involved in vitamin B1 biosynthesis, and HydG, which is involved in the biosynthesis of the metal cofactor of iron-iron hydrogenases. We obtained novel insights of the reaction of tyrosine cleavage catalyzed by these enzymes, providing a better understanding of this emerging group in the rSAM enzyme superfamily.
107

Étude structurale des protéine arginine méthyltransférases : reconnaissance des substrats et conception rationnelle de modulateurs / Structural study of protein arginine methyltransferases : substrate recognition and structure-based design of modulators

Marechal, Nils 14 September 2018 (has links)
Les protéine arginine méthyltransférases (PRMT) sont impliquées dans de nombreux processus cellulaires, incluant la régulation de l’expression des gènes, le contrôle de l’épissage, le maintien de l’intégrité du génome et la transduction du signal. De nombreuses études montrent que la dérégulation de l’activité des PRMT est associée au développement de pathologies, et en particulier de cancers. Les PRMT constituent ainsi une des nouvelles cibles potentielles en chimiothérapie. Les travaux présentés dans ce manuscrit portent sur trois cibles : PRMT2, PRMT3 et PRMT4/CARM1. Combinant des approches biochimiques, biophysiques et structurales (cristallographie et cryo- microscopie électronique), ces travaux comportent deux aspects : (I) comprendre au niveau atomique la régulation de la réaction de méthylation des protéines (reconnaissance protéines-protéines et interactions entre modifications post-traductionnelles) ; (II) découvrir des inhibiteurs spécifiques et puissants de plusieurs PRMT cibles. / Protein arginine methyltransferases (PRMT) are involved in many cellular processes, including gene expression regulation, splicing control, maintenance of genome integrity and signal transduction.Since deregulation of those biological processes appears to be implicated in the pathogenesis of different diseases, PRMTs have emerged as potential new targets for the development of novel therapeutic modulators. Despite the large amount of biological and structural data on PRMTs, two challenges remain to be solved by structural biology ; (I) understanding how PRMTs recognize and bind their full-length substrates ; (II) revealing how PRMTs achieve specific arginine methylation on different target sites. The works presented here focused on 3 targets: PRMT2, PRMT3 and PRMT4/ CARM1. We used biochemical, biophysical and structural methods (bio-crystallography and cryo- electron microscopy) to decipher structural clues that drive PRMT-substrate recognition. We developed new chemical probes that can be used in early drug discovery for the conception of PRMT inhibitors.
108

Estudo numérico da variabilidade das massas de água do Mar de Ross nos séculos XX e XXI / Numerical Assessment of the Ross Sea Water Masses Variability in the 20 th and 21 st Centuries

Tonelli, Marcos Henrique Maruch 06 November 2009 (has links)
O oceano desempenha papel fundamental na configuração e manutenção do clima da Terra, sendo considerado um dos componentes principais do sistema climático.Diversos estudo foram conduzidos para avaliar as mudanças nos processos climáticos e como o clima, em contrapartida, é afetado por tais mudanças. O presente trabalho visa investigar o impacto das mudanças climáticas na formação de massas de água do oceano austral. Foram analisados resultados de simulação numérica para os séculos XX e XXI pelo modelo CCSM3 para os cenários 20c3m e SRESA1B do IPCC. Através da técnica de separação de mássas de água Análise Otimizada de Parâmetros Múltiplos (OMP) foram identificadas 3 massas de água no Mar de Ross: Água Profunda Circumpolar (CDW); Água da Plataforma de Gelo (ISW); Água de Plataforma de Baixa Salinidade (LSSW). A ISW, precursora da Água de Fundo Antártica (AABW), apresenta maior variação espacial tornando-se mais rasa no século XX e assumindo camadas mais profundas no século XXI. A variação da ISW está relacionada à variação do Modo Anular Sul (SAM) e à variação do gelo marinho. / It has been known for a long time that the ocean plays the most important role on Earth\'s heat budget, what turns it into a major component of the global climate system. Therefore, many studies have been made to assess whether features of climate processes are changing and how may climate itself be affected by these changes. This work aims to look at the impact of climate changes on water masses formation in the Southern Ocean. Results from the 20th century and SRESA1b CCSM3/NCAR simulation (1870 to 2100) were analyzed using the Optimum Multiparameter Analysis (OMP) to separate water masses. Three water masses were identified in the Ross Sea: Circumpolar Deep Water (CDW); Ice Shelf Water (ISW); Low Salinity Shelf Water (LSSW). Simulation results have shown that the ISW gets shallower during the 20th century and then, during the 21stcentury, it gets deeper and occupies the deepest layer by 2100 while it flows towards higher latitudes as AABW. Much closely to what has been shown by observational studies, water masses formation in the Southern Ocean is intrinsically linked to atmospheric vaiability modes, such as the southern annular mode--SAM, and to sea ice variation.
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Indes néerlandaises et culture chinoise. Deux traductions malaises du Roman des Trois Royaumes (1910-1913) / Dutch East Indies and Chinese Culture. Two Malay Translations of the Romance of the Three Kingdoms (1910-1913)

Song, Ge 08 December 2018 (has links)
Au début des années 1880, un grand nombre de traductions malaises de romans chinois émanant de descendants de Chinois (appelés en malais peranakan) parurent aux Indes néerlandaises sous la forme d’ouvrages imprimés. Nous avons choisi d’en étudier deux, parues simultanément pendant les années 1910-1913, à un moment où la communauté chinoise d’Insulinde essayait de repenser son identité culturelle et politique, sous les angles littéraire, philologique, historique et sociologique. Il s’agit de deux traductions complètes du Sanguo yanyi 三国演义, le plus remarquable des romans historiques chinois traitant de la période des Trois Royaumes. Une analyse textuelle, nous a permis de constater que les traducteurs des deux Sam Kok (titre abrégé couramment utilisé en Indonésie pour désigner le « Roman des Trois Royaumes »), qui n’avaient pourtant qu’une éducation chinoise du premier degré et une connaissance du malais en usage dans les milieux urbains de Java, mais une grande volonté, ont réussi à exprimer toutes les valeurs littéraires et culturelles du Sanguo yanyi. Afin d’examiner l’impact des Sam Kok sur communauté chinoise, nous les avons replacés dans leur contexte historique et dans l’ensemble des traductions parues pendant les années 1880-1910. Nous sommes parvenue ainsi à montrer que grâce à ces traductions, et particulièrement celles du « Roman des Trois Royaumes », les peranakan ont pu obtenir une certaine compréhension de l’histoire et de la culture du pays de leurs ancêtres, lesquelles constituaient aussi une partie de leur passé. / In the early 1880s, the descendants of Chinese immigrants (called Peranakan in Malay) achieved and printed a large number of Malay translations of Chinese novel in the Dutch Indies. We chose to study two translations published simultaneously during the years 1910-1913 when the Chinese community of Insular Southeast Asia was trying to rethink its cultural and political identity from the literary, philological, historical and sociological angles. The research is about two complete translations of the Sanguo yanyi 三国演义, the most remarkable Chinese historical novels that depict the period of Three Kingdoms. Through textual analysis, we found that although the translators of two Sam Kok (abbreviated title commonly used in Indonesia to refer to the “Romance of the Three Kingdoms”) had some rudimentary Chinese education and knowledge of the language Malay used in the urban areas of Java, they exhibited a great willingness to express all the literary and cultural values of the novel Sanguo yanyi. In order to examine the impact of Sam Kok on the Chinese community, we have put them in their historical context and compare them with other Malay translations published during 1880-1910. Consequently, we are able to assert that, through those translations, especially those of Romance of the Three Kingdoms, the peranakan have acquired some understanding of the history and culture of their ancestral country, which also constituted their past.
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Estudo numérico da variabilidade das massas de água do Mar de Ross nos séculos XX e XXI / Numerical Assessment of the Ross Sea Water Masses Variability in the 20 th and 21 st Centuries

Marcos Henrique Maruch Tonelli 06 November 2009 (has links)
O oceano desempenha papel fundamental na configuração e manutenção do clima da Terra, sendo considerado um dos componentes principais do sistema climático.Diversos estudo foram conduzidos para avaliar as mudanças nos processos climáticos e como o clima, em contrapartida, é afetado por tais mudanças. O presente trabalho visa investigar o impacto das mudanças climáticas na formação de massas de água do oceano austral. Foram analisados resultados de simulação numérica para os séculos XX e XXI pelo modelo CCSM3 para os cenários 20c3m e SRESA1B do IPCC. Através da técnica de separação de mássas de água Análise Otimizada de Parâmetros Múltiplos (OMP) foram identificadas 3 massas de água no Mar de Ross: Água Profunda Circumpolar (CDW); Água da Plataforma de Gelo (ISW); Água de Plataforma de Baixa Salinidade (LSSW). A ISW, precursora da Água de Fundo Antártica (AABW), apresenta maior variação espacial tornando-se mais rasa no século XX e assumindo camadas mais profundas no século XXI. A variação da ISW está relacionada à variação do Modo Anular Sul (SAM) e à variação do gelo marinho. / It has been known for a long time that the ocean plays the most important role on Earth\'s heat budget, what turns it into a major component of the global climate system. Therefore, many studies have been made to assess whether features of climate processes are changing and how may climate itself be affected by these changes. This work aims to look at the impact of climate changes on water masses formation in the Southern Ocean. Results from the 20th century and SRESA1b CCSM3/NCAR simulation (1870 to 2100) were analyzed using the Optimum Multiparameter Analysis (OMP) to separate water masses. Three water masses were identified in the Ross Sea: Circumpolar Deep Water (CDW); Ice Shelf Water (ISW); Low Salinity Shelf Water (LSSW). Simulation results have shown that the ISW gets shallower during the 20th century and then, during the 21stcentury, it gets deeper and occupies the deepest layer by 2100 while it flows towards higher latitudes as AABW. Much closely to what has been shown by observational studies, water masses formation in the Southern Ocean is intrinsically linked to atmospheric vaiability modes, such as the southern annular mode--SAM, and to sea ice variation.

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