Les stilbénoïdes, sont des composés phénoliques majoritairement issus du règne végétal. La Vigne par l’intermédiaire du vin et du raisin est la principale source alimentaire de stilbènes. La mise en évidence de leur rôle dans les mécanismes de défense des plantes et leurs activités biologiques, y compris sur l’Homme, en font un sujet d’étude en plein essor. L’un des objectifs de cette thèse a été de développer un ensemble de stratégies à la fois analytiques et préparatives utilisant la Chromatographie de Partage Centrifuge (CPC) pour l’étude et l’obtention de ces molécules. Dans un premier temps, nous avons développé une approche de couplage entre cette technique et un spectromètre à Résonance Magnétique Nucléaire (RMN) par l’intermédiaire d’un système d’Extraction sur Phase Solide automatisé (EPS). Dans un second temps, nous avons mis au point un ensemble de méthodes et d’approches séparatives permettant d’obtenir ces composés. Nous avons, grâce au développement d’une méthodologie de dosage de solvants par spectrométrie RMN, étudié une gamme dérivée d’une gamme très utilisée en CPC, l’ARIZONA. Nous avons montré que ces systèmes dérivés, peuvent être utilisés au travers de stratégies d’élution telles que des pas et des gradients afin d’optimiser les séparations. L’une des finalités de notre travail est d’offrir des méthodes permettant d’obtenir ces composés dans des quantités et des qualités suffisantes pour pouvoir constituer une chimiothèque interne au laboratoire pouvant prétendre à s’intégrer dans la Chimiothèque Nationale. Une dernière partie fait état du développement d’outils informatiques, dont la création d’une base de donnée Libre pour les chercheurs en Substances Naturelles. / Stilbenoids are phenolic compounds mostly found in the vegetable kingdom. Vine through wine and grape is the main source of stilbenes in the human diet. The involvement of these compounds in plants resistance mechanisms and their diverse biological activities, including on the human health are continuously highlighted. Making this topic a fast-growing one. One of the objectives of this thesis has been to develop a whole set of analytical and preparative strategies using Centrifugal Partition Chromatography (CPC) in order to study and obtain these molecules. Over a first phase, we developed a hyphenated approach between this technique and Nuclear Magnetic Resonance (NMR) through an automated Solid Phase Extraction (SPE) system. Then, we developed a set of separative methods and approaches with the aim of obtaining these compounds. Then, we carried out the development of a solvent quantifications methodology using NMR spectrometry. This allowed us to study a spin-off scale of a widely-used solvent systems collection called ARIZONA. We showed that these systems are good candidates for different elution strategies using steps and gradients with the aim to optimize separations. One of our purpose was to provide methods for effective and efficient purification of these compounds. This would allow, together with a lab-scale compounds library, their integration into the Chimiothèque Nationale, a nationwide chemical library. Last part accounts for computer tools development, including the creation of a Free database system for Natural Substances researcher.

Doctorado en Ciencias mención Microbiología. / Acidithiobacillus thiooxidans es una bacteria que obtiene energía metabólica y poder reductor a partir de la oxidación de compuestos reducidos de azufre. En estado natural, esta bacteria se encuentra junto con otros microorganismos participantes del consorcio de biolixiviación de sulfuros metálicos formando estructuras multicelulares llamadas biopelículas sobre la superficie de sulfuros minerales. Las células están embebidas en una matriz de sustancias poliméricas extracelulares (EPS) las cuales se componen principalmente de exopolisacáridos, proteínas y lípidos. Se ha descrito que la solubilización de los minerales sulfurados metálicos está mediada por estos EPS. Sin embargo, la composición de los EPS y su rol exacto en la solubilización de sulfuros metálicos ha sido caracterizado solamente en la bacteria oxidadora de hierro y azufre Acidithiobacillus ferrooxidans, aunque las demás especies de Acidithiobacillus que son capaces de oxidar solamente compuestos reducidos del azufre son fundamentales en estos procesos de lixiviación. En base a estos antecedentes, nos propusimos caracterizar alguno de los EPS y los mecanismos moleculares involucrados en la formación de biopelículas en la especie modelo At. thiooxidans. En un trabajo previo, se identificó un gen putativo que codifica para una proteína de unión a c-di-GMP PelD, la cual está caracterizada en Pseudomonas aeruginosa formando parte de un complejo multiproteico de membrana involucrado en vii la biosíntesis del exopolisacárido Pel. Al analizar el contexto genético del gen pelD, se identificó un putativo operón con una estructura similar al operón canónico identificado en P. aeruginosa. El análisis comparativo entre los genomas disponibles de las bacterias acidófilas que están presentes en los entornos minerales ácidos reveló que este operón sólo está presente en los genomas de At. thiooxidans y At. caldus. Ante este resultado, este trabajo se enfocó en comprender cuál sería la importancia de este exopolisacárido en la formación de biopelículas de At. thiooxidans sobre la superficie de azufre elemental. La medición de los niveles de transcrito mediante qPCR mostró que los genes pelA, pelD y wcaG del putativo operón presentan un mayor de expresión en células adheridas que en células planctónicas. El análisis de azúcares de superficie mediante el uso de lectinas identificó la presencia de N-acetil-galactosamina y N-acetil-glucosamina. Tratando de dilucidar algunas de las señales que regulan la producción de Pel, se descubrió que la adición exógena de la molécula de Quorum Sensing (QS) 3-oxo-C8 AHL incrementa la transcripción de los genes pelA y pelD. Finalmente, se procedió a obtener una cepa mutante nula en el gen pelD mediante recombinación homóloga. Luego de analizar el DNA de esta cepa, se realizaron análisis de adherencia y formación de biopelículas sobre la superficie de azufre elemental mediante microscopía electrónica y de epifluorescencia. La mutación ΔpelD afectó la estructura de la biopelícula al reducir la presencia de N-acetil-galactosamina y N-acetilglucosamina en la superficie, pero adicionalmente provocó un incremento en la viii producción de estructuras filamentosas que rodean a las células. Para resolver la incógnita sobre la naturaleza de estas fibras, se realizaron análisis comparativos preliminares de la expresión de proteínas extracelulares. El análisis del sobrenadante de los cultivos y de las proteínas del EPS reveló un cambio en producción de proteínas secretadas al medio. En base a estos resultados es posible concluir que el exopolisacárido Pel producido por la bacteria biominera At. thiooxidans juega un rol estructural en la formación de biopelículas sobre la superficie de azufre elemental y que la regulación de su síntesis involucra a las vías del QS y del c-di-GMP. / Acidithiobacillus thiooxidans is a bacterium that obtains metabolic energy and reducing power from the oxidation of reduced sulfur compounds. In the natural state, this bacterium is found along with other microorganisms that are members of the metal sulfides bioleaching consortium forming multicellular structures called biofilms on the surface of mineral sulfides. The cells are embedded in a matrix of extracellular polymeric substances (EPS) which are composed mainly of exopolysaccharides, proteins and lipids. It has been described that the solubilization of the metal sulfide minerals is mediated by these EPS. However, the composition of the EPS and their exact role in the solubilization of metal sulfides has been characterized only in the iron and sulfur oxidizer bacterium Acidithiobacillus ferrooxidans, although the other Acidithiobacillus species that are only capable of oxidizing reduced sulfur compounds are important in these leaching processes. Based on this background, we set out to characterize some of the EPS and the molecular mechanisms involved in biofilm formation in the model species At. thiooxidans. In a previous work it was identified a putative gene encoding a c-di-GMP binding PelD protein, which is characterized as part of a multiprotein membrane complex involved in Pel exopolysaccharide biosynthesis in Pseudomonas aeruginosa. x When we were analyzing the genetic context of the pelD gene, a putative operon with a structure similar to the canonical operon identified in P. aeruginosa was identified. Comparative analysis between available genomes of acidophilic bacteria that are present in acidic mineral environments revealed that this operon is only present in the genomes of At. thiooxidans and At. caldus. Given this result, this work focused on understanding the importance of this exopolisaccharide in biofilm formation of At. thiooxidans on the surface of elemental sulfur. Measurement of transcript levels by qPCR showed that pelA, pelD and wcaG genes of the putative operon exhibit a greater expression in attached cells than in planktonic cells. The analysis of surface sugars by the use of lectins identified the presence of N-acetyl-galactosamine and N-acetyl-glucosamine. Trying to elucidate some of the signals that regulates the production of Pel, it was discovered that the exogenous addition of Quorum Sensing (QS) molecule of 3-oxo-C8 AHL increases the transcription of pelA and pelD genes. Finally, a pelD gene null mutant strain was obtained by homologous recombination. After analyzing the DNA of this strain, adherence and biofilm formation analysis were performed on the elemental sulfur surface by electronic and epifluorescence microscopy. The ΔpelD mutation affected the structure of the biofilm by reducing the presence of N-acetyl-galactosamine and N-acetyl glucosamine on the surface, but additionally caused an increase in the production of fibrillar structures xi surrounding the cells. To solve the unknown about the nature of these fibers, preliminary comparative analysis of extracelluar protein expression were performed. Analysis of the culture supernatant and proteins from EPS revealed a change in production of secreted proteins to the medium. Based on these results it is possible to conclude that the Pel exopolisaccharide produced by the biomining bacterium At. thiooxidans plays a structural role at biofilm formation on the surface of elemental sulfur and that the regulation of its synthesis involves QS and c-di-GMP pathways. / Proyectos regulares Fondecyt 1120295 y 1160702 y beca Conicyt 21120064 por aportar el financiamiento durante el desarrollo de la tesis.

Cette recherche est une contribution à l’identification des procédures de guidage et des styles d’enseignement mis en oeuvre dans l’enseignement par situation complexe en éducation physique et sportive (EPS). Notre volonté vise à clarifier la façon dont les experts (du point de vue de l’enseignement pas SC) mettent en oeuvre et accompagnent l’activité des élèves, en tenant compte de différents facteurs (caractéristiques de l’enseignant, nature de l’habileté motrice sollicitée dans l’activité physique, sportive et artistique (APSA), et nature de la situation pédagogique) qui peuvent influencer les pratiques. Notre travail est positionné sur un cadre scientifique métissé, dont la logique originale vise à développer et étayer des pratiques pédagogiques grâce à l’éclairage des sciences de l’intervention et de la psychologie sociale appliquée à l’enseignement de l’EPS. Notre démarche empirique s’appuie sur des observations ordinaires de séances d’enseignement en EPS. Dans l’ensemble des résultats observés, les trois études mettent en avant quelques caractéristiques fixes dans les modalités de guidage des enseignants lors d’une situation complexe. Malgré les différences observées (modes de guidage) dans les trois études selon les différents facteurs définis auparavant, d’une façon ou d’autre, les enseignants observés préservent l’autonomie des élèves dans leur activité de recherche de solution en SC. En revanche, le guidage directif centré sur l’aspect technique spécifie le comportement des enseignants lors des situations ciblées (situations didactiques). Ainsi, du point de vue de l’expertise disciplinaire (expérience approfondie dans la pratique et l’enseignement de l’APSA), nos résultats mettent en évidence qu’une expérience professionnelle (en tant que enseignant d’EPS) ne semble pas compenser une absence d’expérience dans l’APSA enseignée. / This research is a contribution to the identification of guidance procedures and teaching styles implemented in teaching by complex situation in physical education (PE). Our aim is to clarify the way used by experts to implement and regulate the students’ activity in this type of education, taking in account different factors (characteristics of the teacher, nature of the motor skill sought in the APSA, and the nature of the pedagogical situation) that may influence this teaching practice. Our work is positioned on a mixed scientific framework, which original construction logic aims to develop and support teaching practices through the help of science of education and social psychology applied to education. Our empirical approach is based on ordinary observations of PSE teaching sessions. In all of the deduced results, the three studies highlight some unchanged characteristics in the guiding methods of teachers in a complex situation. Despite the noticed differences (guiding modes) in the three studies according to the different factors previously defined, in one way or another, the observed teachers preserves students' autonomy in a solution-seeking activities. On the other hand, teachers’ behavior in targeted situations was characterized by directive guidance focused on the technical aspect (didactic situations). Thus, from a disciplinary point of view, (in-depth experience in the practice and teaching of APSA), our results show that professional experience (as a teacher of PSE) does not seem to compensate for the lack of experience in the APSA taught.

Espumas à base de amido possuem limitações para utilização como embalagens na indústria alimentícia, principalmente, devido à alta hidrofilicidade e fragilidade. Para melhorar essas propriedades, torna-se necessário o uso de plastificantes e outros aditivos, como proteínas e fibras lignocelulósicas, ou ainda um aditivo fonte desses recursos, como a torta de gergelim obtida como resíduo do processamento do gergelim. Sendo assim, o objetivo deste trabalho foi desenvolver e caracterizar espumas à base de amido de mandioca adicionadas de 0 – 40 % (m/m) de resíduo de gergelim, produzidas pelo processo de expansão térmica, a fim de avaliar a influência do aditivo nas propriedades físicas, morfológicas e mecânicas dos materiais obtidos para utilização como embalagens para alimentos. A adição do resíduo resultou em espumas com menores espessuras e densidade aparente, bem como, maior capacidade de expansão dos materiais. Além disso, apresentaram melhores propriedades mecânicas e, em geral, menores capacidade de absorção de água e adsorção de água em baixas umidades relativas, em relação aos materiais compostos somente por amido. Embora as propriedades mecânicas das espumas sejam influenciadas pelas condições de umidade relativa de armazenamento, as espumas contendo 20 % de resíduo (20R) apresentaram uma combinação de propriedades no ensaio de tração (resistência à tração e módulo de elasticidade) que podem ser consideradas comparáveis às amostras de bandejas comercias de poliestireno expandido (EPS), nas três umidades relativas avaliadas (33, 53 e 90 %). Os resultados obtidos nos ensaios de flexão dessas espumas indicaram que as mesmas foram mais rígidas e menos flexíveis do que as amostras de EPS. A adição de 20 % de resíduo resultou em importantes melhorias nas propriedades físicas e mecânicas em comparação às espumas à base de amido de mandioca, além de apresentarem menos defeitos morfológicos do que os observados em espumas com maiores teores do resíduo (30 e 40 %). Foram realizados testes de aplicação das espumas 20R no acondicionamento de dois tipos de alimentos com diferentes teores de umidade: bolo (23 %) e brócolis (91 %), em comparação ao armazenamento em embalagens comerciais de EPS. A partir dos resultados obtidos para a variação de umidade, perda de massa e propriedades mecânicas na flexão das embalagens, foi observado que as espumas propostas não foram adequadas para o acondicionamento das amostras de brócolis, apresentando alta absorção de umidade e deformações após três dias de contato com o alimento. Por outro lado, as espumas 20R mostraram bom desempenho no acondicionamento das amostras de bolo, não apresentando mudanças significativas nas propriedades mecânicas no período de 3 a 9 dias de armazenamento. Dessa forma, o resíduo de gergelim em combinação com o amido de mandioca mostrou elevado potencial para o desenvolvimento de espumas que podem ser utilizadas como embalagens para alimentos com baixos teores de umidade, sendo necessários estudos mais detalhados, considerando principalmente aspectos de segurança para utilização de resíduos em produtos em contato direto com alimentos. / Starch based foams have limitations for use as food packaging, mainly due to high hydrophilicity and fragility. In order to improve these properties it is necessary the use of plasticizers and others additives, such as lignocellulosic fibers and proteins, or an additive source of these constituents like sesame cake, which it is obtained from sesame processing. In this way, the main objective of this work was to develop and characterize starch based foams added with 0 – 40 % (w/w) of sesame residue to evaluate the influence of this additive on physical, morphological and mechanical properties of materials for using as food packaging. The foams were produce by thermal expansion process. Residue addition resulted in foams with smaller thickness and density, as well as greater expansion capacity of the materials produced. In addition, foams incorporated with residue exhibited better mechanical properties and, in general, lower water capacity absorption and water adsorption at low relative humidities compared to foams made only with starch. Although mechanical properties of the foams are affected by storage humidity conditions, foams added with 20 % of residue (20R) showed tensile properties (tensile strength and tensile elasticity modulus) that can be considered comparable to expanded polystyrene (EPS) commercial trays for different relative humidities evaluated (33, 53 and 90 %). Flexural properties indicated that starch foams produced was tougher and less flexible than EPS commercial trays. Addition of 20 % of sesame residue on cassava starch-based foams resulted in relevant improvements compared to foams without residue. Besides that, fewer morphological defects were noted, as observed in foams with higher residue content (30 and 40 %). Thus, 20R formulation was selected to carrying out applicability tests of starch-based foams in packaging of two types of food with different moisture content: cake (23 %) and broccoli (91 %) compared to EPS commercial packaging. From the results obtained for moisture variation, loss of weight and flexural properties of the foams, it was found that the material proposed was not applicable to package broccoli samples. Due to high water absorption by the foams alterations on the shape were noted in the materials after 3 days in contact with this food. Nonetheless, foams based on cassava starch and 20 % of sesame residue exhibited a good performance during storage time of cake samples (9 days). It was not observed any effect on flexural mechanical properties for 3 to 9 days of storage. Thereby, sesame cake added to cassava starch showed high potential to developing foams that could be used as packaging for low moisture food. Additionally, more detailed studies are necessary, especially considering safety aspects mainly for using agricultural residues directly in contact with food products.

L’objet de notre recherche est d’étudier les expériences corporelles des adolescents obèses pour comprendre leur processus d’engagement dans les situations obligatoires en EPS. Les études scientifiques montrent une activité physique faible chez les adolescents obèses. Analysées par le filtre de l’anthropologie existentiale, c’est-à-dire des êtres en train d’exister, les stratégies étudiées ne décrivent que le mode majeur de la réalité, conforme aux attentes scolaires. En s’inscrivant dans les théories pragmatiques (Quéré, 1997), dans la sociologie de l’expérience (Dubet, 1994) et dans l’anthropologie existentiale (Piette, 2015), cette thèse apporte un regard nouveau, en appréhendant, par le mode mineur de la réalité, les expériences corporelles, spatiales, temporelles et relationnelles de quatre élèves. L’étude ethnographique a permis la reconstruction de leurs expériences corporelles à partir de données audiovisuelles, d’observations non participantes et d’entretiens de l’élève et de son entourage. Contrairement au regard porté par les études précédentes, nos résultats mettent en exergue une richesse de l’expérience corporelle des adolescents. Le mode mineur révèle des repères corporels, spatiaux, temporels et relationnels singuliers sur lesquels les élèves s’appuient pour rester engagés dans la situation tout en se dégageant des contraintes les plus insoutenables pour eux. Les modes de dégagements et le processus de reposité permettent de rendre compte autrement des contraintes normatives véhiculées en EPS. Les adolescents obèses traduisent corporellement ces normes en les faisant vivre dans une partition chorégraphique organisée à partir de l’équilibre subtil de l’agir sur le subir. Derrière l’incorporation des normes émerge le pouvoir créateur de la personne dans son existence. / We focus our research on the study of body experience for obese teenagers, in order to understand the engagement process when facing compulsory Physical Education situations. Scientific studies show a rather low level of physical activity among overweight adolescents. Analyzed in the light of existential anthropology (meaning « of people existing »), the strategies reviewed only describe the major reality mode, which meets school expectations. Fitting in the science of pragmatic theories (Quéré, 1997), experience sociology (Dubet, 1994) and existential anthropology (Piette, 2015), this thesis provides a new perspective by getting to grips with the body, space, time and relationship experience of four students, through the minor reality mode.The ethnographic study enabled the reconstruction of their body experience based on audiovisual data, non-participating observations and interviews with the students and their family and friends. Contrary to previous studies findings, our results highlight the richness of teenager body experience . The minor mode reveals remarkable body, space, time and relationship landmarks, which the student can use to stay engaged in situations, whilst breaking out of his/her unbearable constraints. The decommitment modes and the process of « reposité » lead to a better or different understanding of normative constraints conveyed in Physical Education. Overweight teenagers tend to « bodily translate » these norms by turning them into a choreographic score, based on the delicate balance between « doing » and « enduring ». Behind the incorporation of standards emerges the creative power of individuals in their existence.

Grâce à leurs propriétés particulières dues à leur petite taille, les nanomatériaux (dimension < 100 nm) sont utilisés dans de nombreuses applications grand public (cosmétique, matériaux nanostructurés,...). Cependant, leur présence grandissante inquiète car leur impact potentiel sur les humains et l'environnement reste mal connu. Cette étude est consacrée à une compréhension approfondie des interactions physicochimiques et biologiques entre deux modèles cellulaires présents dans l'environnement : Synechocystis (cyanobactérie contribuant au maintien de la biosphère) et Escherichia coli (bactérie des intestins des mammifères) avec des nanoparticules d'oxyde de cérium (abondance environnementale croissante, ex : additif au diesel). <br />La complexité de l'étude des nanoparticules nécessite une approche différente (multidisciplinaire) de celle des tests de toxicité utilisés pour les composés classiques. En effet, nous montrons que les paramètres physicochimiques (stabilité, agrégation, dissolution et état de surface) des nanoparticules dans le milieu de contact, influencent fortement la toxicité observée sur les cellules. De plus, les interactions physicochimiques (floculation, adsorption, mécanismes redox) sont liées au modèle biologique, en particulier à la présence d'exopolysaccharides (chez Synechocystis) comme barrière naturelle entre la paroi cellulaire et les nanoparticules. La composition du milieu de dispersion des nanoparticules (notamment son pH) a aussi une influence majeure sur la toxicité (survie et intégrité membranaire). Tandis que pour E. coli, ce sont majoritairement les nanoparticules qui provoquent la mortalité (confirmé par analyses métabonomiques par RMN).

Thauera aminoaromatica MZ1T is an exopolysaccharide (EPS)-producing Gram negative bacterium isolated from the wastewater treatment plant of a major industrial chemical manufacturer as the causal agent for poor sludge dewatering. It shares common features with other known Thauera spp. (i.e. Thauera aromatica, and Thauera selenatis), being capable of degrading aromatic compounds anaerobically and using acetate and succinate as carbon sources. It is unique among the Thauera spp. in its production of abundant EPS which results in viscous bulking and poor sludge dewaterability. In this respect, it is similar to Azoarcus sp. EbN1 and BH72. Thaueran is the proposed name for EPS produced by MZ1T for research purpose. The focus of this research is to fully characterize the microorganism and identify and characterize the genes responsible for thaueran synthesis and export through bioinformatics, transposon mutagenesis, gene clone and expression, reverse transcriptase quantitative real time PCR, and genome sequencing and annotation. Ultimately, this knowledge will contribute to control of viscous bulking and sludge dewatering problems. However, a broader range of important environmental biotechnical processes may be forthcoming from understanding thaueran synthesis. They may include thaueran remedial solutions for heavy metal and radionuclide immobilization, anaerobic carbon channeling and sequestration, greenhouse gas mitigation through acetate incorporation into thaueran, and novel applications such as thaueran-mediated wound healing. Sequencing of MZ1T genome has been accomplished through collaboration with the Joint Genome Institute (JGI). The genome size is 4.5 Mbp, GC content is 68.3%, and there are 4,092 protein coding genes. Three putative thaueran gene clusters were found within the genome. One tight cluster with a size of 20.67kb encoding 14 genes may contain most necessary genes for thaueran formation and export. Another two clusters are loosely organized. Through transposon mutagenesis, mutants not producing abundant thaueran and not flocculating have been obtained and verified, and were further used in reverse transcriptase quantitative real time PCR to compare the differential expression levels of the presumable EPS genes among mutants, wild type MZ1T and under different growth conditions. The results indicated a correlation of the expression level of the test genes and the abundance of EPS.

The functional group composition of acid polysaccharides was determined after isolation using cross-flow ultrafiltration, radiolabeling with 234Th(IV) and other isotopes, and separation using isoelectric focusing (IEF) and polyacrylamide gel electrophoresis (PAGE). Phosphate and sulphate concentrations were determined from cultured bacterial and phytoplankton colloid, particulate and colloidal samples collected from the Gulf of M??xico (GOM). Characterization of the 234Th(IV)-binding biomolecule was performed using ion chromatography (IC), and gas chromatography-mass spectrometry (GC-MS). Radiotracer experiments and culture experiments were conducted in determining the binding environment of the 234Th(IV)-binding ligand (i.e., sorption onto suspended particles), as well as the origin of the ligand in seawater systems. In all samples, 234Th(IV) isoelectric focusing profiles indicated that 49% to 65% of the 234Th(IV) labeled EPS from Roseobacter gallaeciensis, Sagittula stellata, Emiliania huxleyi, Synechococcus elongatus and GOM Station 4-72m was found at a pHIEF of 2 in the IEF spectrum. The carboxylic acid group appeared at the same pHIEF as 234Th(IV) for EPS from Roseobacter gallaeciensis, Emiliania huxleyi, Synechococcus elongatus and GOM colloidal organic matter sample. The phosphate group appeared at the same pHIEF as 234Th(IV) for EPS from Roseobacter gallaeciensis, and Synechococcus elongatus sample. The sulphate group was found at the same pHIEF as 234Th(IV) for EPS from S. elongatus and GOM colloidal organic matter sample. The total polysaccharide content was only 14% and 8%, uronic acids were approximately 5.4% and 87.1%, and total protein content was 2.6% and 6.2% of total carbon content of Sagittula stellata and Synechococcus elongatus, respectively. Monosaccharides identified in both Sagittula stellata and Synechococcus elongatus were galactose, glucose, and xylose in common. In addition, Sagittula stellata contained mannose and Synechococcus elongatus had galactoglucuronic acid. Thus, depending on the species, the size, structural composition, and functional groups of the 234Th(IV)-binding, acidic polysaccharides will vary. From these observations, it is concluded that the steric environment and not necessarily the exact functional group might actually be responsible for thorium-234 complexation to macromolecular organic matter. This research helped to improve our understanding of the observed variability in POC/234Th ratios in the ocean and provided insights into factors that regulate organic carbon export fluxes.

Cette étude porte sur les conations de socialisation chez les enseignants d'Education Physique et Sportive (EPS),éléments d'explication des choix de contenus d'enseignement proposés en sport collectif. Parallèlement, elle permet derepérer, dans les propositions de contenus, les différentes conceptions de la socialisation qu'ont les enseignants.Le cadre théorique retenu associe le modèle individualiste de Weber (1911) dans lequel l'individu gère ses actions dansl'art de se débrouiller et le modèle conatif développé par Bui-Xuân (1993, 1998), où l'inclination à agir dirigée par unsystème de valeurs incorporées va orienter l'action de l'être humain.L'hypothèse de travail était que le choix des contenus d'enseignement visant l'objectif de socialisation par les sportscollectifs détermine l'étape conative de socialisation dans laquelle se situe l'enseignant.La méthode s'appuie sur trois techniques principales et complémentaires :- L'analyse de la littérature scientifique et professionnelle,- Une enquête par questionnaire (n = 280),- Deux séries d'entretiens compréhensifs (avant : n = 9 ; après : n = 5).Les résultats mettent en évidence cinq étapes conatives : à l'étape 1 (émotionnelle), où l'enseignant, non spécialiste desport collectif, ne peut pas suivre la logique de socialisation précisée dans les textes car il est d'abord confronté auxobstacles à la socialisation ; à l'étape 2 (fonctionnelle), l'enseignant, non spécialiste de sport collectif, fait référence àl'objectif de socialisation présent dans les textes, mais il tâtonne et essaie de solliciter les élèves en fonction de leursdispositions ; à l'étape 3 (technique), l'enseignant, spécialiste ou non, est convaincu que les sports collectifs favorisent lasocialisation, et pour ce faire, il impose toutes les règles (socialisation passive) ; à l'étape 4 (contextuelle), l'enseignant,spécialiste de sport collectif, permet aux élèves de prendre des initiatives (socialisation active), mais celles-ci restent sousl'influence du contexte de la classe et du sport collectif retenu ; enfin, à l'étape 5 (expertise et création), l'élève est partieprenante de sa socialisation (socialisation active) qui est cependant placée sous l'influence des choix didactiques etpédagogiques de l'enseignant.Il est démontré, in fine, que le passage d'une étape à une autre répond à des conditions d'accumulation de facteurshiérarchisés.L'étude débouche sur la thèse : les conations de socialisation chez les enseignants d'EPS déterminent le choix des formeset des contenus d'enseignement en sport collectif.

El objetivo de los estudios de farmacogenética es aumentar la eficacia y la seguridad de los fármacos. En este trabajo hemos analizado la posible asociación entre los polimorfismos en los genes ECA, COMT y CYP2D6 con el riesgo de desarrollar efectos extrapiramidales (EPS) en pacientes tratados con antipsicóticos. Como estudios secundarios hemos realizado un estudio descriptivo de la frecuencia de los polimorfismos anteriormente mencionados en nuestra población general de referencia y hemos analizado la posible asociación entre estos polimorfismos con el riesgo de desarrollar esquizofrenia. Para el análisis de los cuatro polimorfismos en el gen CYP2D6 analizados en este trabajo hemos diseñado un método de genotipado basado en la combinación de una PCR multiplex con una reacción de minisecuenciación. Los resultados obtenidos de este trabajo han sido los siguientes :1) en el estudio de riego de EPS la edad actuó como un factor protector. La dosis y la potencia de los APs por producir EPS, en cambio, resultaron ser un factor de riesgo; 2) Los genotipos ECA ID y ECA DD presentan una tendencia a actuar como un factor de riesgo de desarrollar EPS en los pacientes con trastorno bipolar tratados con antipsicóticos; 3) El genotipo COMTLL y el alelo COMTL confieren, respectivamente, un 90% y un 70% de protección frente a los EPS en los pacientes con trastorno bipolar; 4) Los haplotipos A-G y A-A formados por los polimorfismos COMTVal158Met y el polimorfismo COMTA-278G han resultado estar relacionados con la aparición de EPS inducidos por APs en los pacientes con trastorno bipolar; 5) Los polimorfismos ECAI/D y COMTVal158Met presentan efectos independientes y no sinérgicos en relación con la parición de EPS en los pacientes con trastorno bipolar; 6) Para el grupo de pacientes esquizofrénicos, ni el polimorfismo COMTVal158Met ni el haplotipo formado por éste y el polimorfismo COMTA-278G parecen estar relacionados con la aparición de EPS inducidos por los APs, ya que no se ha encontrado ninguna asociación; 7) El polimorfismo CYP2D6*4 actúa como un factor de riesgo de desarrollar EPS en pacientes tratados con antipsicóticos, con un riesgo de hasta cinco veces mayor. Este polimorfismo ha resultado ser el principal contribuyente al genotipo PM en nuestra población. Para el genotipo PM se ha observado una tendencia a actuar como un factor de riesgo a desarrollar estos efectos adversos; 8) Los otros tres polimorfismos analizados en el gen CYP2D6 (CYP2D6*3, *5 y *6) no modificaron el riesgo de EPS inducidos por APs; 9) Las frecuencias de los polimorfismos analizados en este trabajo obtenidas en nuestra población general de referencia, han resultado muy similares a las descritas en otras poblaciones caucásicas; 10) El genotipo ECA DD y el alelo ECA D se comportan como un factor protector para la esquizofrenia, reduciendo el riesgo en un 70% y un 50%, respectivamente; 11) El polimorfismo COMTVal158Met, los haplotipos formados por este polimorfismo y el COMTA-278G, y los cuatro polimorfismos analizados en el gen CYP2D6 no modificaron el riesgo de sufrir esquizofrenia; 12) El método diseñado para la detección de los cuatro polimorfismos en el gen CYP2D6 mostró una total concordancia con las técnicas estándares para todos los genotipos. / Pharmacogenetic studies could help to predict antipsychotic (AP) efficacy and toxicity susceptibility and facilitate the choice of treatment. AP treatment-emergent extra pyramidal symptoms (EPS) are frequent and serious acute adverse reactions to AP drugs. AP acts by competing with dopamine to block the dopaminergic receptors: this competition results in both efficacy and toxicity. Therefore, EPS depends on drug and dopamine availability and also on dopamine D2 receptor density.In this study we examined whether polymorphism in the ACE and COMT gene, potentially related to dopamine levels, and polymorphism in the CYP2D6 gene, potentially related to AP levels, are risk factors for AP treatment-emergent EPS or schizophrenia. Moreover, we performed a descriptive study of these polymorphisms in our reference population. For the detection of CYP2D6 polymorphisms we have designed a method to detect all four polymorphisms in a single reaction.The results of the present study indicate that: 1) ECA ID and ECA DD genotypes show a tendency to act as risk factors for the development EPS in bipolar disorder patients; 2) COMTLL genotype and COMTL allele act as protective factors for EPS in bipolar disorder patients; 3) Two haplotypes formed by COMTVal158Met and COMTA-278G polymorphisms are correlated with EPS in bipolar disorder patients; 4) In schizophrenic patients, neither COMTVal158Met nor the haplotype formed by this polymorphism and COMTA-278G polymorphism seems to be correlated with EPS; 5) CYP2D6*4 polymorphism acts as a risk factor for the development EPS in patients treated with AP. PM genotype showed a tendency to act as a risk factor for the development of theses adverse effects; 6) CYP2D6*3, *5 and *6 polymorphisms in CYP2D6 gene did not modify EPS risk; 7) ECA DD genotype and ECA D allele act as protector factors for schizophrenia; 8) Polymorphism frequencies obtained in our general population were similar to those described in other Caucasian populations; 9) The method designed for the detection of the four polymorphisms in the CYP2D6 gene showed complete concordance with other standard techniques for all genotypes.