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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.
181

Educação ambiental no licenciamento: um estudo do programa de educação ambiental na transamazônica - município de Brasil Novo-Pará

MAFRA, Kelly Soares 12 September 2014 (has links)
Submitted by Edisangela Bastos (edisangela@ufpa.br) on 2015-05-20T21:22:03Z No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Dissertacao_EducacaoAmbientalLicenciamento.pdf: 1930250 bytes, checksum: f78a98ec896c77c880affdcf96fa296a (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2015-05-22T12:41:28Z (GMT) No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Dissertacao_EducacaoAmbientalLicenciamento.pdf: 1930250 bytes, checksum: f78a98ec896c77c880affdcf96fa296a (MD5) / Made available in DSpace on 2015-05-22T12:41:28Z (GMT). No. of bitstreams: 2 license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Dissertacao_EducacaoAmbientalLicenciamento.pdf: 1930250 bytes, checksum: f78a98ec896c77c880affdcf96fa296a (MD5) Previous issue date: 2014 / O presente trabalho apresenta um estudo sobre o Programa de Educação Ambiental da BR-230 realizado no município brasileiro de Brasil Novo, estado do Pará, por ocasião do processo de licenciamento ambiental da obra de asfaltamento da rodovia BR-230 (Transamazônica). O objetivo refere-se a uma análise dos resultados das ações realizadas pelo Programa de Educação Ambiental da BR-230 no município de Brasil Novo, no período de 2009 a 2011. O referencial teórico-metodológico parte de uma abordagem qualitativa que privilegia as análises sobre o Programa de Educação Ambiental numa perspectiva de Educação Ambiental crítica. A coleta e a análise de dados foram realizadas a partir de entrevistas semiestruturadas direcionadas aos professores da educação básica e complementadas com informações buscadas em documentos ligados ao Programa. Os resultados da pesquisa dimensionam a importância da reflexão teórica sobre os processos pedagógicos utilizados para a realização da Educação Ambiental no âmbito do Programa. A pesquisa revela a partir da análise das falas dos sujeitos entrevistados que há um esforço de articulação entre a proposta de ação desenvolvida pelo Programa e as questões ambientais da realidade local; as ações proporcionaram aos sujeitos novos conhecimentos e vivências que são significativas nas suas práticas docentes, como na elaboração de projetos e no aprimoramento do planejamento pedagógico. Portanto as ações ambientais realizadas pelo Programa da BR-230 são relevantes e contribuem para uma reflexão crítica sobre o modo de vida e de cultura dos sujeitos envolvidos, entretanto, percebe-se nos depoimentos a necessidade de ampliação da visão conservacionista de educação como possibilidade de ampliação da perspectiva de ação. / This paper presents a study on the environmental education program of the BR-230 held in the Brazilian city New Brazil, state of Para, during the environmental licensing process of the work of paving of BR-230 (Trans) highway. The objective refers to an analysis of the results of actions taken by the Environmental Education Program of BR-230 in the municipality of Novo Brazil, from 2009 to 2011 The theoretical and methodological framework of a qualitative approach that focuses on the analysis the Environmental Education Program from the perspective of critical environmental education. The collection and analysis of data was carried out semi-structured interviews directed to basic education teachers and supplemented with information sought documents related to the Program. The results of the survey scale the importance of theoretical reflection on pedagogical processes used to carry out the Environmental Education Program under the. The research reveals from the analysis of the statements of interviewees that there is a joint effort between the proposed action developed by the Program and environmental issues of local reality; the actions provided subject to new knowledge and experiences that are meaningful in their teaching practices, as in the preparation of projects and the improvement of educational planning. Therefore the environmental actions taken by the BR-230 program are relevant and contribute to a critical reflection on the lifestyle and culture of the individuals involved, however, it is seen in the testimonies the need to overcome the conservationist vision as a possible expansion of prospect of action.
182

Nos tempos do gegê : a modernidade e as ambiguidades

Oliveira, Lívia Sudare de 01 March 2013 (has links)
Made available in DSpace on 2016-12-08T16:51:58Z (GMT). No. of bitstreams: 1 livia.pdf: 1739171 bytes, checksum: 79f0c24eccf17279fa13548a4539f2e6 (MD5) Previous issue date: 2013-03-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Knowing that the Teatro de Revista (Revue) is a genre that deals with current events, this study aims to analyze seven revue texts written between 1929 and 1945 to see if there was still political debate on the Revue of that period. The period Getulio Vargas was president was chosen as a temporal cut since its censorship is claimed responsible for the down fall of political contents on the Revue. Therefore, this project seeks to understand the laugh mechanisms used by the Revue authors in attempt to hoax the censorship. It intent also to point out the political themes discussed on the Revue texts to comprehend how the Teatro de Revista dealt with the political and social events it faced, such as the 1930 revolution, the Estado Novo coup and the World War II. The aesthetical changes the genre went through and the way it relates with the political changes the country experienced are also being studied here. The cultural policy created during the Estado Novo is being revisited to enable the uptake about its relation with the Teatro de Revista and it is asked if this genre was a part of the motion for the building of a so called Brazilian theatre / Sabendo que o Teatro de Revista é gênero que trabalha com a atualidade, o objetivo deste estudo é analisar sete textos revisteiros produzidos entre 1929 e 1945, de forma a perceber se ainda havia discussões políticas na Revista desse período. O governo de Getúlio Vargas foi escolhido como recorte temporal, pois a censura é responsabilizada pela derrocada do teor político no Teatro de Revista. Assim, busca-se entender que mecanismos do riso foram utilizados pelos autores revisteiros para burlar a censura. Intenta-se elencar a temática política discutida nos textos revisteiros para compreender como o Teatro de Revista lidava com os acontecimentos políticos e sociais que presenciava. Estão sob foco também as mudanças estéticas pelas quais o gênero passou e a forma como isso está relacionado com as mudanças políticas ocorridas simultaneamente no país, como a Revolução de 1930, o golpe do Estado Novo e a Segunda Guerra Mundial. A política cultural do Estado Novo é revisitada para possibilitar entendimento sobre sua relação com o Teatro de Revista e se esse gênero esteve inserido na proposta de construção de um teatro dito brasileiro
183

Instinto e asfalto : os contos impuros de Feliz ano novo, de Rubem Fonseca

Coronel, Luciana Paiva January 1998 (has links)
Esta dissertação pretende comprovar a existência de uma relação profunda entre o texto ficcional dos contos de Feliz Ano Novo, publicado em 1975, e o contexto histórico da época. Partindo de um panorama da produção artística e cultural dos anos 60 e 70, o trabalho insere as opções temático-formais desta obra no referido contexto histórico e artístico e busca evidenciar a maneira pela qual tal contexto se faz presente na linguagem da obra, que recria artisticamente a tensão e a violência do período. A linguagem configura um discurso metaficcional que contém, em sua forma banal e calculada, uma profunda reflexão sobre o papel da literatura no mundo mercantilizado que a cerca. Assim, através da metalinguagem, a narrativa dos contos problematiza a História e realiza uma das poucas formas de subversão ainda ao alcance de um produto artístico: escapar ao destino de ser um mero bem de consumo e converterse em instrumento de problematização da própria lógica dos bens culturais de consumo.
184

Instinto e asfalto : os contos impuros de Feliz ano novo, de Rubem Fonseca

Coronel, Luciana Paiva January 1998 (has links)
Esta dissertação pretende comprovar a existência de uma relação profunda entre o texto ficcional dos contos de Feliz Ano Novo, publicado em 1975, e o contexto histórico da época. Partindo de um panorama da produção artística e cultural dos anos 60 e 70, o trabalho insere as opções temático-formais desta obra no referido contexto histórico e artístico e busca evidenciar a maneira pela qual tal contexto se faz presente na linguagem da obra, que recria artisticamente a tensão e a violência do período. A linguagem configura um discurso metaficcional que contém, em sua forma banal e calculada, uma profunda reflexão sobre o papel da literatura no mundo mercantilizado que a cerca. Assim, através da metalinguagem, a narrativa dos contos problematiza a História e realiza uma das poucas formas de subversão ainda ao alcance de um produto artístico: escapar ao destino de ser um mero bem de consumo e converterse em instrumento de problematização da própria lógica dos bens culturais de consumo.
185

Instinto e asfalto : os contos impuros de Feliz ano novo, de Rubem Fonseca

Coronel, Luciana Paiva January 1998 (has links)
Esta dissertação pretende comprovar a existência de uma relação profunda entre o texto ficcional dos contos de Feliz Ano Novo, publicado em 1975, e o contexto histórico da época. Partindo de um panorama da produção artística e cultural dos anos 60 e 70, o trabalho insere as opções temático-formais desta obra no referido contexto histórico e artístico e busca evidenciar a maneira pela qual tal contexto se faz presente na linguagem da obra, que recria artisticamente a tensão e a violência do período. A linguagem configura um discurso metaficcional que contém, em sua forma banal e calculada, uma profunda reflexão sobre o papel da literatura no mundo mercantilizado que a cerca. Assim, através da metalinguagem, a narrativa dos contos problematiza a História e realiza uma das poucas formas de subversão ainda ao alcance de um produto artístico: escapar ao destino de ser um mero bem de consumo e converterse em instrumento de problematização da própria lógica dos bens culturais de consumo.
186

Étude sur le rôle des mutations de novo dans l’étiologie génétique de la schizophrénie

Girard, Simon L. 08 1900 (has links)
La schizophrénie est une maladie psychiatrique grave qui affecte approximativement 1 % de la population. Il est clairement établi que la maladie possède une composante génétique très importante, mais jusqu’à présent, les études ont été limitées au niveau de l’identification de facteurs génétiques spécifiquement liés à la maladie. Avec l’avènement des nouvelles avancées technologiques dans le domaine du séquençage de l’ADN, il est maintenant possible d’effectuer des études sur un type de variation génétique jusqu’à présent laissé pour compte : les mutations de novo, c.-à-d. les nouvelles mutations non transmises de manière mendélienne par les parents. Ces mutations peuvent avoir deux origines distinctes : une origine germinale au niveau des gamètes chez les parents ou une origine somatique, donc au niveau embryonnaire directement chez l’individu. L’objectif général de la présente recherche est de mieux caractériser les mutations de novo dans la schizophrénie. Comme le rôle de ces variations est peu connu, il sera également nécessaire de les étudier dans un contexte global au niveau de la population humaine. La première partie du projet consiste en une analyse exhaustive des mutations de novo dans la partie codante (exome) de patients atteints de schizophrénie. Nous avons pu constater que non seulement le taux de mutations était plus élevé qu’attendu, mais nous avons également été en mesure de relever un nombre anormalement élevé de mutations non-sens, ce qui suggère un profil pathogénique. Ainsi, nous avons pu fortement suggérer que les mutations de novo sont des actrices importantes dans le mécanisme génétique de la schizophrénie. La deuxième partie du projet porte directement sur les gènes identifiés lors de la première partie. Nous avons séquencé ces gènes dans une plus grande cohorte de cas et de contrôles afin d’établir le profil des variations rares pour ces gènes. Nous avons ainsi conclu que l’ensemble des gènes identifiés par les études de mutations de novo possède un profil pathogénique, ce qui permet d’établir que la plupart de ces gènes ont un rôle réel dans la maladie et ne sont pas des artéfacts expérimentaux. De plus, nous avons pu établir une association directe avec quelques gènes qui montrent un profil aberrant de variations rares. La troisième partie du projet se concentre sur l’effet de l’âge paternel sur le taux de mutations de novo. En effet, pour la schizophrénie, il est démontré que l’âge du père est un facteur de risque important. Ainsi, nous avons tenté de caractériser l’effet de l’âge du père chez des patients en santé. Nous avons observé une grande corrélation entre l’âge du père et le taux de mutations germinales et nous avons ainsi pu répertorier certaines zones avec un grand nombre de mutations de novo, ce qui suggère l’existence de zone chaude pour les mutations. Nos résultats ont été parmi les premiers impliquant directement les mutations de novo dans le mécanisme génétique de la schizophrénie. Ils permettent de jeter un nouveau regard sur les réseaux biologiques à l’origine de la schizophrénie en mettant sous les projecteurs un type de variations génétiques longtemps laissé pour compte. / Schizophrenia is a severe psychiatric disorder that affects roughly 1% of the general population. It has been clearly demonstrated that the disease possesses a strong genetic component, but thus far, studies have had limited success in identifying key schizophrenia genes. With the advent of new DNA sequencing technologies it is now possible to study a type of genetic variation that has been previously looked over: de novo mutations (new mutations not transmitted by parents) The main aim of the present thesis is to better characterize de novo mutations in schizophrenia. As the role of these variations is not very well known, it was also necessary to study them in a global context in the human population. The first part of our project was to do a comprehensive study of de novo mutations found in the coding section (exome) of patients affected with schizophrenia. We found that the mutation rate was higher than expected. We also observed an aberrant number of nonsense mutations, which suggests a pathogenic profile of mutations. Thus, we strongly suggested that de novo mutations are key players in the genetic mechanism of schizophrenia. The second part of the work builds on the genes bearing mutations identified in the exome sequencing analysis. We sequenced these genes in a larger cohort of cases and controls in order to establish the profile of rare variants for these genes. We were able to conclude that the global mutational profile of the genes identified during de novo mutation studies are indeed pathogenic, which confirms that some of those genes are really involved in the disease and are not sequencing artefacts. Additionally, we were also able to identify some genes that had an aberrant rare variation profile. The third part of the work aimed to characterize the paternal age effect on the de novo mutation rate. Indeed, in schizophrenia, it has been shown numerous times that paternal age is a risk factor for the disease. Thus, we have chosen to characterize this effect in a cohort of healthy subjects. We were able to observe a high correlation between paternal age and an elevated germline mutation rate. We were also able to confirm the existence of genomic regions that present an elevated number of de novo mutations, supporting the notion of mutational hotspots. Our results were amongst the first to be published on the scientific area to directly involve de novo mutations in the genetic mechanism of schizophrenia. Those results bring new clues on the biological networks underlying schizophrenia by investigating a genetic variation type long overlooked.
187

Cartographie des cassures bicaténaires du remodelage chromatinien du spermatide et développement des outils techniques associés. / Genome-wide mapping of DNA double-strand breaks during spermatid chromatin remodeling and development of associated tools

Grégoire, Marie-Chantal January 2016 (has links)
Résumé : La phase haploïde de la spermatogenèse (spermiogenèse) est caractérisée par une modification importante de la structure de la chromatine et un changement de la topologie de l’ADN du spermatide. Les mécanismes par lesquels ce changement se produit ainsi que les protéines impliquées ne sont pas encore complètement élucidés. Mes travaux ont permis d’établir la présence de cassures bicaténaires transitoires pendant ce remodelage par l’essai des comètes et l’électrophorèse en champ pulsé. En procédant à des immunofluorescences sur coupes de tissus et en utilisant un extrait nucléaire hautement actif, la présence de topoisomérases ainsi que de marqueurs de systèmes de réparation a été confirmée. Les protéines de réparation identifiées font partie de systèmes sujets à l’erreur, donc cette refonte structurale de la chromatine pourrait être génétiquement instable et expliquer le biais paternel observé pour les mutations de novo dans de récentes études impliquant des criblages à haut débit. Une technique permettant l’immunocapture spécifique des cassures bicaténaires a été développée et appliquée sur des spermatides murins représentant différentes étapes de différenciation. Les résultats de séquençage à haut débit ont montré que les cassures bicaténaires (hotspots) de la spermiogenèse se produisent en majorité dans l’ADN intergénique, notamment dans les séquences LINE1, l’ADN satellite et les répétions simples. Les hotspots contiennent aussi des motifs de liaisons des protéines des familles FOX et PRDM, dont les fonctions sont entre autres de lier et remodeler localement la chromatine condensée. Aussi, le motif de liaison de la protéine BRCA1 se trouve enrichi dans les hotspots de cassures bicaténaires. Celle-ci agit entre autres dans la réparation de l’ADN par jonction terminale non-homologue (NHEJ) et dans la réparation des adduits ADN-topoisomérase. De façon remarquable, le motif de reconnaissance de la protéine SPO11, impliquée dans la formation des cassures méiotiques, a été enrichi dans les hotspots, ce qui suggère que la machinerie méiotique serait aussi utilisée pendant la spermiogenèse pour la formation des cassures. Enfin, bien que les hotspots se localisent plutôt dans les séquences intergéniques, les gènes ciblés sont impliqués dans le développement du cerveau et des neurones. Ces résultats sont en accord avec l’origine majoritairement paternelle observée des mutations de novo associées aux troubles du spectre de l’autisme et de la schizophrénie et leur augmentation avec l’âge du père. Puisque les processus du remodelage de la chromatine des spermatides sont conservés dans l’évolution, ces résultats suggèrent que le remodelage de la chromatine de la spermiogenèse représente un mécanisme additionnel contribuant à la formation de mutations de novo, expliquant le biais paternel observé pour certains types de mutations. / Abstract : Germline mutations may arise from several endogenous and exogenous mechanisms in both male and female. However, recent next-generation sequencing (NGS) data confirmed that de novo mutations arise primarily in males. This observation suggests that specific spermatogenesis events are involved in the male mutation bias. One potential origin for male-driven mutations is the differentiation of spermatids into spermatozoa, which involves one of the most striking and global chromatin remodeling processes, where histone-bound chromatin is converted into highly condensed protaminated DNA toroid. Using pulse-field gel electrophoresis and comet assay on flow cytometry sorted cells, it was established that chromatin remodeling process is characterized by a transient surge in DNA double strand breaks (DSBs) in the whole population of murine spermatids, which get repaired by the end of spermiogenesis. Using a highly active nuclear extract and immunofluorescences, topoisomerases and markers of DNA repair systems were shown at these steps. Since haploid cells cannot rely on homologous recombination for templated DNA repair, it was hypothesized that this process may be genetically unstable and largely responsible for the observed male de novo mutations bias. Although very challenging, a method allowing the specific genome-wide mapping of DSBs using NGS was developed to establish the genomic distribution of DSBs during chromatin remodeling. It was shown that intergenic regions were enriched in DSBs, particularly LINE1, satellite DNA and simple repeats. Motif finding on potential hotspots showed that proteins from FOX and PRDM families may be implicated. Although homologous recombination cannot take place during spermiogenesis, an enrichment in BRCA1 motif was found, which is also known to be implicated in NHEJ and removal of topoisomerase adducts. Topoisomerase-like SPO11 motif was also enriched suggesting that the meiotic machinery may also be implicated during chromatin remodeling. Moreover, although DSBs tend to accumulate in intergenic regions, gene ontology analysis of hotspot-containing genes showed a marked enrichment in genes related to neurons and brain development. This result hence supports the fact that neurological disease associated mutations are also male biased and associated with advanced paternal age. Since DSB formation during spermiogenesis is conserved through evolution, these results suggest that chromatin remodeling in spermatids represents a significant component in the reported male de novo mutation bias.
188

Étude sur le rôle des mutations de novo dans l’étiologie génétique de la schizophrénie

Girard, Simon L. 08 1900 (has links)
La schizophrénie est une maladie psychiatrique grave qui affecte approximativement 1 % de la population. Il est clairement établi que la maladie possède une composante génétique très importante, mais jusqu’à présent, les études ont été limitées au niveau de l’identification de facteurs génétiques spécifiquement liés à la maladie. Avec l’avènement des nouvelles avancées technologiques dans le domaine du séquençage de l’ADN, il est maintenant possible d’effectuer des études sur un type de variation génétique jusqu’à présent laissé pour compte : les mutations de novo, c.-à-d. les nouvelles mutations non transmises de manière mendélienne par les parents. Ces mutations peuvent avoir deux origines distinctes : une origine germinale au niveau des gamètes chez les parents ou une origine somatique, donc au niveau embryonnaire directement chez l’individu. L’objectif général de la présente recherche est de mieux caractériser les mutations de novo dans la schizophrénie. Comme le rôle de ces variations est peu connu, il sera également nécessaire de les étudier dans un contexte global au niveau de la population humaine. La première partie du projet consiste en une analyse exhaustive des mutations de novo dans la partie codante (exome) de patients atteints de schizophrénie. Nous avons pu constater que non seulement le taux de mutations était plus élevé qu’attendu, mais nous avons également été en mesure de relever un nombre anormalement élevé de mutations non-sens, ce qui suggère un profil pathogénique. Ainsi, nous avons pu fortement suggérer que les mutations de novo sont des actrices importantes dans le mécanisme génétique de la schizophrénie. La deuxième partie du projet porte directement sur les gènes identifiés lors de la première partie. Nous avons séquencé ces gènes dans une plus grande cohorte de cas et de contrôles afin d’établir le profil des variations rares pour ces gènes. Nous avons ainsi conclu que l’ensemble des gènes identifiés par les études de mutations de novo possède un profil pathogénique, ce qui permet d’établir que la plupart de ces gènes ont un rôle réel dans la maladie et ne sont pas des artéfacts expérimentaux. De plus, nous avons pu établir une association directe avec quelques gènes qui montrent un profil aberrant de variations rares. La troisième partie du projet se concentre sur l’effet de l’âge paternel sur le taux de mutations de novo. En effet, pour la schizophrénie, il est démontré que l’âge du père est un facteur de risque important. Ainsi, nous avons tenté de caractériser l’effet de l’âge du père chez des patients en santé. Nous avons observé une grande corrélation entre l’âge du père et le taux de mutations germinales et nous avons ainsi pu répertorier certaines zones avec un grand nombre de mutations de novo, ce qui suggère l’existence de zone chaude pour les mutations. Nos résultats ont été parmi les premiers impliquant directement les mutations de novo dans le mécanisme génétique de la schizophrénie. Ils permettent de jeter un nouveau regard sur les réseaux biologiques à l’origine de la schizophrénie en mettant sous les projecteurs un type de variations génétiques longtemps laissé pour compte. / Schizophrenia is a severe psychiatric disorder that affects roughly 1% of the general population. It has been clearly demonstrated that the disease possesses a strong genetic component, but thus far, studies have had limited success in identifying key schizophrenia genes. With the advent of new DNA sequencing technologies it is now possible to study a type of genetic variation that has been previously looked over: de novo mutations (new mutations not transmitted by parents) The main aim of the present thesis is to better characterize de novo mutations in schizophrenia. As the role of these variations is not very well known, it was also necessary to study them in a global context in the human population. The first part of our project was to do a comprehensive study of de novo mutations found in the coding section (exome) of patients affected with schizophrenia. We found that the mutation rate was higher than expected. We also observed an aberrant number of nonsense mutations, which suggests a pathogenic profile of mutations. Thus, we strongly suggested that de novo mutations are key players in the genetic mechanism of schizophrenia. The second part of the work builds on the genes bearing mutations identified in the exome sequencing analysis. We sequenced these genes in a larger cohort of cases and controls in order to establish the profile of rare variants for these genes. We were able to conclude that the global mutational profile of the genes identified during de novo mutation studies are indeed pathogenic, which confirms that some of those genes are really involved in the disease and are not sequencing artefacts. Additionally, we were also able to identify some genes that had an aberrant rare variation profile. The third part of the work aimed to characterize the paternal age effect on the de novo mutation rate. Indeed, in schizophrenia, it has been shown numerous times that paternal age is a risk factor for the disease. Thus, we have chosen to characterize this effect in a cohort of healthy subjects. We were able to observe a high correlation between paternal age and an elevated germline mutation rate. We were also able to confirm the existence of genomic regions that present an elevated number of de novo mutations, supporting the notion of mutational hotspots. Our results were amongst the first to be published on the scientific area to directly involve de novo mutations in the genetic mechanism of schizophrenia. Those results bring new clues on the biological networks underlying schizophrenia by investigating a genetic variation type long overlooked.
189

Développement de nouveaux outils pour la détermination de la structure de macromolécules biologiques par diffraction aux rayons X : application aux protéines membranaires et aux grands complexes protéiques / Developement of new tools for biological macromolecular structure determination by X-ray diffraction : application to membrane proteins and to large protein complexes.

Talon, Romain 06 June 2012 (has links)
Cette thèse concerne le développement de complexes de lanthanide et leur utilisation pour résoudre les structures de macromolécules biologiques par diffraction des rayons X, en particulier celles de protéines membranaires et de complexes protéiques de grande taille. Les complexes de lanthanide sont formés d’un atome de lanthanide et d’un ligand chimique qui assure une liaison non-covalente avec les surfaces protéiques. Introduits dans les cristaux de protéine, ces derniers constituent une sous-structure qui, déterminée par les méthodes de phasage de novo courantes, permet de résoudre la structure de la macromolécule d’intérêt. La première partie de ce travail de thèse est une étude menée sur la grande famille des complexes picolinates de lanthanide, complexes luminescents dont la fixation au sein des cristaux est aisément décelable. En premier lieu, nous avons défini les conditions dans lesquelles le complexe tris-dipicolinate de lanthanide peut être utilisé ainsi que ses éventuelles capacités à promouvoir la cristallisation (effet supramoléculaire). En second lieu, un nouveau complexe, dérivé du précédent, a été développé au cours de cette thèse : le tris-hydroxymethyltriazoledipicolinate de lanthanide (« [Ln(TDPA)3]3- »). Il nous a permis de réaliser un phasage de novo très précis conduisant à la détermination des structures du lysozyme de blanc d’œuf de poule et de la thaumatine de Thaumatococcus daniellii à haute résolution. Par ailleurs, différents ligands pour ce nouveau complexe ont été synthétisés par chimie-click, nous permettant de créer une panoplie de complexes uniques et des complexes hybrides. Nous avons montré que cette nouvelle famille de complexes présente une meilleure affinité pour les protéines permettant leur utilisation à de faibles concentrations. Les essais menés avec ces LnTDPA ont aussi permis d’entrevoir l’importance de la charge globale pour expliquer l’effet supramoléculaire. En troisième lieu, un tripicolinate cagé, le LnTNTPA, a également été évalué. Constitué d’une cage chimique de charge globale nulle, nous avons montré que ce nouveau complexe luminescent est le seul de cette famille picolinate qui puisse être utilisé en présence d’ions divalents. Dans la seconde partie de cette thèse, nous décrivons l’utilisation des complexes de lanthanide pour le phasage de protéines multimériques de grandes tailles par les méthodes de phasage de novo. Premièrement, la structure de l’aminopeptidase dodécamérique PhTET1-12s de 480 kDa a été déterminée à 4 Å de résolution à l’aide du tris-dipicolinate d’europium. Ceci nous a permis de démontrer que les complexes de lanthanide peuvent être utilisés pour obtenir un phasage précis, même à basse résolution. Deuxièmement, les complexes de lanthanide issus de l'imagerie médicale ont aussi permis de déterminer la structure de trois nouvelles enzymes homotétramériques de la famille des malate déshydrogénases. Ces structures permettent d’apporter de nouveaux éclaircissements sur l'adaptation halophile. Enfin, en utilisant ces enzymes en tant que bibliothèque de fonctions chimiques, nous avons pu mettre en place une nouvelle approche méthodologique pour comprendre finement les modes d'interaction des complexes de lanthanide. / This thesis aims to develop lanthanide complexes for solving biological macromolecular structures, especially membrane proteins and large protein complexes. Lanthanide complexes are composed of a lanthanide atom and a chemical ligand, which provides non-covalent binding to protein surfaces. Incorporated in protein crystals, they make up the substructure, determined by the widely-used de novo phasing methods, needed for solving the whole protein structure. The first part of the present work shows a study of the luminescent lanthanide picolinate complexes family, easily detectable in protein crystals. First, we defined the conditions in which the known lanthanide tris-dipicolinate can be used and we examined its possible ability to promote protein crystallization (supramolecular effect). Secondly, a newly developed lanthanide tris hydroxymethyltriazoledipicolinate complex "[Ln(TDPA)3]3-", derived from this previous complex, allowed us to obtain a very precise de novo phasing for solving the high-resolution structure of the hen egg white lysozyme and the thaumatin from Thaumatococcus daniellii. Besides, various ligands for these new complexes were synthetized by click chemistry, enabling us to create both unique complexes outfit and hybrid complexes. We have shown that this new complexes family presents a better affinity for proteins allowing their use at very low concentrations. Tests conducted with those LnTDPA have also evidenced the importance of complex global charge to explain the supramolecular effect. Third, a caged tripicolinate, the LnTNTPA, was evaluated. Characterized by a neutrally charged chemical cage, we have shown that this new luminescent complex is the only one of the picolinate complexes family that can be used in the presence of divalent ions. In the second part of this thesis, we describe the use of lanthanide complexes for phasing large multimeric proteins by de novo phasing methods. First, the structure of the 480 kDa dodecameric aminopeptidase PhTET1-12s was solved at 4 Å resolution by using the europium tris-dipicolinate which demonstrates that the lanthanide complexes can be used to obtain an accurate phasing, even at low resolution. Secondly, the lanthanide complexes from medical imaging also helped to solve the structures of three new homotetrameric enzymes from the malate dehydrogenases family. Those structures provide new insights into halophilic adaptation. Finally, by using these enzymes as a library of chemical functions, we developed a new methodological approach for a better understanding of the precise binding modes of those lanthanide complexes.
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[en] THE SEARCH FOR LUÍS SÉRGIO PERSON: A MOVIEMAKER AGAINST THE MAINSTREAM / [pt] EM BUSCA DE LUIZ SÉRGIO PERSON: UM CINEASTA NA CONTRAMÃO 1960 - 1976

CANDIDA MARIA MONTEIRO RODRIGUES DA COSTA 27 November 2006 (has links)
[pt] A proposta dessa pesquisa é situar a obra do cineasta paulista Luiz Sérgio Person (1936-1976) no cenário cultural brasileiro dos anos 1960. O documentário que sua filha, Marina Person, realiza para entender a perda do pai é o ponto de partida do estudo. O filme Person (1999) traz questões sobre o resgate da memória, a constituição da identidade e a subjetividade da narrativa autobiográfica. Do filme emerge a obra desse original realizador que promove uma virada temática no cinema brasileiro de sua época. Person inaugura a problemática do homem de classe média urbano, vítima do desenvolvimento econômico. Em sua trajetória destacam-se os debates travados sobre o conceito nacional-popular, o movimento do Cinema Novo, o cinema de autor e ainda o cinema do Terceiro Mundo. Tais debates colocam Person em confronto com o grupo cinemanovista e enquadram o universo desse estudo. / [en] The purpose of the research is to evaluate the work of São Paulo moviemaker Luís Sérgio Person (1936-1976) in the Brazilian cultural scenario of the 1960s. The starting point was the documentary currently being made by Person´s daughter, Marina Person, for understanding the loss of her father. The documentary Person (1999) discusses his artistic legacy, his identity as a moviemaker and the subjectivity of the autobiographical streamline. It also places under the spotlight the work of a unique moviemaker who managed to introduce a new concept to the Brazilian cinema of his time. Person opens the path to discuss the problematic meanders that surround the urban, middle-class individual as a prey to the contingencies introduced by the economic development. Highlights of those new paths include discussions on the national-popular ideas, the Cinema Novo trends, the concept of a cinéma d´auteur and the so-called Third World cinema. All these questions contribute to place Person´s output against the mainstream of his time, at the same time they outline the boundaries of the present study.

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