Les membranes modèles représentent un outil indispensable pour l'étude des membranes biologiques, elles ont en effet grandement contribué à leur description. Dans ce travail, nous nous sommes intéressés à l'étude de la coexistence de phases liquide-ordonnée (lo) et liquide-désordonnée (ld) au sein de membranes modèles de type LUV (« Large Unilamellar Vesicle »). Nous avons cherché en premier lieu à mettre au point une méthodologie permettant de détecter la formation de la phase lo et d'estimer quantitativement la fraction membranaire Φo en phase lo dans des LUVs de composition ternaire PC/SM/Chol (phosphatidylcholine / sphingomyéline / cholestérol), capable d'induire une coexistence de phase. Pour cela, les propriétés d'auto-extinction de fluorescence et de distribution sélective en fonction de la phase lipidique d'une sonde fluorescente unique (C12NBD-PC) ont été mises à profit. La deuxième partie de notre travail a été consacrée à l'étude de la solubilisation par le détergent Triton X-100 des membranes de LUVs présentant une coexistence de phase lo/ld. Nous avons cherché à démontrer qu'il était possible d'extraire la fraction membranaire se trouvant strictement en phase lo. Pour cela, les transitions de structure induites par l'interaction du Triton X-100 avec des LUVs à 4°C ont été étudiées par une procédure de séparation par gradient de densité. Nous avons tenté d'évaluer le rapport effectif approprié détergent/lipides nous permettant d'isoler les fractions résistantes correspondant aux domaines en phase lo existant au niveau de la membrane des LUVs avant l'addition de détergent.

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase. Activated FAK is crucial to many biological processes, such as cell proliferation, migration, and survival, all of which have been implicated in the progression and development of cancer. Tyrosine 925 is a Src-phosphorylation site that is located within the FAT domain in the C-terminal of FAK. It has been suggested that the helix containing Y925 (Helix 1) has to come out of the FAT bundle and the region flanking Y925 has to adopt β-strand conformation. In order to phosphorylate, the mechanisms promoting the required structural changes are unclear. So, Molecular Dynamics (MD) and Constant Force Molecular Dynamics (CFMD) simulations were used to study what makes Y925 accessible for phosphorylation. Under thermal fluctuation only and in the presence or the absence of LD motifs, MD simulations suggest that H1 does not appear to have a propensity to leave the bundle adopt β-strand conformation. Then, two different load scenarios were used; axial and perpendicular with 100 pN constant load applied to H1 N-terminus with the two paxillin LD motifs constrained. For both load scenarios, H1 has two different behaviors: typical and atypical. In the axial load scenario, the first two residues at the N-terminal of H1 (besides Y925) have low propensity to unfold. However, H1 does not show any proclivity to leave the bundle. For the perpendicular load scenario with the absence of P2 (LD motif binds to H1/H4 hydrophobic patch), one simulation out of 21 showed that H1 undergoes the required structural rearrangement. In general, CFMD simulations show that the FAT domain has a very low propensity (3%) to undergo the structural changes needed for Y925 phosphorylation. This has two implications: either mechanical load is insufficient to make Y925 available for phosphorylation and/or this kind of process (structural changes needed for Y925 phosphorylation) is slow process that needs a long time to occur. / text

The initial purpose of this thesis is to begin an exploration into the level of support given by colleges and universities to high-skills lifelong learning in the field of business and management, referred to as executive and professional education (EPE). To properly define level of support several additional undertakings were necessary, including: discovering methods of valuing knowledge to a region, state or country, establishing why participants in EPE programs enroll in them, and developing a set of indicators that would determine the level of support in the higher education system. As the scope of this study in the Unite States is too great, the state of Florida was chosen as a specific case. Florida has a substantial network of both private and public (state) universities and colleges. The thesis concludes with recommendations for advancing the support of EPE in the state of Florida As we move more strongly into the knowledge based economy, and as knowledge creation expands exponentially the need for a continued updating of knowledge and skills in the working community becomes evident. To support this inquiry a set of research questions were developed, as follows: 1 What are the components of relevant EPE? 2 What motivates participants to take part in EPE? 3 What is the level of support of the universities in the state of Florida for EPE? 4 Prepare recommendation based on the findings of the study for the state of Florida to improve support for EPE To address these questions three research methods were employed. Based on the previous experience of the researcher an exploratory case study was written exploring the intricacies of developing a successful EPE department. This exploratory case study served as a basis for developing a survey questionnaire, administered to participants in EPE to determine reasons for their participation. The case study, coupled with certain elements of the questionnaire led to the definition of a group of indicators with which to evaluate the level of support to EPE in a selected group of public and private universities in Florida. This final survey was conducted via the internet by website information of the various universities relative to EPE. Through this research, components of EPE were identified, motivations of participants were ascertained and the level of support by universities was evaluated. The research led to the conclusion that state support of EPE is woefully lacking. Recommendations were developed and included. While this thesis utilized a case, the state of Florida, the researcher believes that the findings and conclusions will be of value to practitioners involved in EPE, as well as to academics studying this area of business education. This research exercise has assisted the researcher in being more effective in managing and developing EPE within his own university. The researcher hopes that the outcome of this research will lead to a more organized approach to EPE in the state of Florida and beyond. As professions and skills are made obsolete in the knowledge economy the need for continued high level lifelong learning becomes increasing important to the sustainability and viability of local, regional, state and national economies.

Ce travail de thèse s'intéresse au sujet de la normalisation dans le champ de la formation à distance. Parmi les multiples propositions de normalisation, notre intérêt porte plus particulièrement sur l'enrichissement du dernier standard de fait IMS-LD. Nous souhaitons de ce fait introduire la notion de pertinence de la normalisation qui signifie la capacité d'IMS-LD de prescrire des scénarios pédagogiques qui répondent réellement à certains principes pédagogiques. Pour notre recherche, nous nous sommes intéressés à une des composantes essentielles de l'apprentissage (Leontiev, 1981), il s'agit de la motivation à apprendre. Ce travail nous a permis d'obtenir trois principaux résultats qui ont été validés en effectuant des études de cas: il s'agit d'abord d'une démarche de scénarisation à posteriori fondée sur les théories de l'activité ; Elle décrit, à partir des traces, le déroulement effectif d'une activité d'apprentissage. Le deuxième résultat est une taxonomie fondée sur la théorie des actes de langage ; Elle permet de traduire quelques composantes de la motivation en un ensemble d'actes de langage observables dans une trace de discussion par " Chat ". Quant au troisième résultat, il s'agit d'un modèle descriptif de la motivation qui rend compte, à partir des traces, des perceptions et ses origines. Ce modèle se sert de notre taxonomie et repose sur le concept des paires adjacentes issu de l'analyse conversationnelle. Enfin, nos conclusions exposent de plus des résultats secondaires et ouvrent des perspectives pour la poursuite de notre question sur la pertinence des normes.

Made available in DSpace on 2014-12-17T15:06:49Z (GMT). No. of bitstreams: 1 HeleneMP_DISSERT.pdf: 527338 bytes, checksum: 6687564238bb07ab571e88d8674bd21c (MD5) Previous issue date: 2010-06-22 / Consid?rant que le Br?sil est un pays consid?r? comme ?non- lecteurs?, nous avons essay? de trouver des solutions pour inverser cette situation d'exclusion sociale ? travers des campagnes et des projets. Le slogan ?tait le moyen de la propagande a propos? ? cet effet. En ?tant un peu ?clairante, il a ?t? consid?r? qu'ils ?taient peut-?tre ins?r? dans un contexte id?ologique, en passant, qui faisait alors partie de l'objet d'?tudes en question et, en cons?quence, l'objectif ?tait d'?tudier comment, dans niveau discursif, les relations sociales de l'id?ologie et du pouvoir dans ces dessins slogans verbaux et des campagnes publicitaires pour encourager la lecture. Nous avons utilis? comme instrument de collecte de donn?es en 2007 slogans projets (sept) et l'intensification des campagnes de publicit? dans les ann?es 1995 ? 2006, peu apr?s la cr?ation de la descendance en 1992, o? son fonctionnement a ?t? analys? et discours id?ologique, en cherchant ? identifier les ?tats effets de sens propos?. Nous avons utilis? pour soutenir la perspective de recherche d'analyse du discours de l'?cole fran?aise, affili?e ? P?cheux. Afin de sens les effets sens des tests a ?t? fait une semi-ouverte aux enseignants qui traitent directement avec l'enseignement de la lecture de l'Institut de l'Enseignement Sup?rieur du Pr?sident-Kennedy, situ? ? Natal / RN. On ?t? appliqu?s 100 questionnaires, parmi lesquels 60 d‟entre eux utilis?s pour l‟analyse. La recherche a d?montr? par l'analyse, que la fa?on d'encourager les gens ? lire se d?place ? travers le mod?le principal de la compr?hension de la lecture ? laquelle les slogans ont ?t? utilis?s, en les int?grant dans un discours dominant, qui ne contribue pas de mani?re significative ? l'augmentation le nombre de lecteurs dans le pays. Gr?ce ? l'analyse des slogans et la r?ception des sujets de recherche, nous nous rendons compte de la diversit? et l'id?ologie sont pr?sents en elles, r?v?lant tout le temps, la compr?hension de la lecture comme une surface pratique, ne mettre en lumi?re certaines de ses fonctions Importantes au sein d‟um contexte ?ducatif plus large / Entendendo que o Brasil ? considerado como um pa?s de n?o leitores , buscou-se encontrar solu??es para se reverter este quadro de exclus?o social por meio de campanhas e projetos. O slogan foi o meio de propaganda proposto para esse fim. Por serem considerados pouco esclarecedores, considerou-se que eles, possivelmente, estavam inseridos em um contexto ideol?gico, passando, ent?o, a fazer parte do objeto de estudo em quest?o e, nesse sentido, o objetivo do trabalho foi investigar como se constr?i, no plano discursivo, as rela??es sociais de ideologia e poder presentes nos slogans verbais dos projetos e campanhas publicit?rias de incentivo ? leitura. Para tanto, utilizou-se como instrumento de coleta 07 (sete) slogans de projetos e campanhas publicit?rias intensificadas nos anos de 1995 a 2006, logo ap?s a cria??o do PROLER em 1992, onde foi analisado seu funcionamento discursivo e ideol?gico, buscando identificar nos enunciados propostos seus efeitos de sentido. Recorreu-se para fundamentar a pesquisa a perspectiva da An?lise do Discurso da Escola Francesa, filiada a Michel P?cheux. A fim de pressentir os efeitos de sentido das campanhas foi aplicado um question?rio semi-aberto aos professores que lidam diretamente com o ensino de leitura do Instituto de Educa??o Superior Presidente Kennedy, situado na cidade de Natal/RN. Foram aplicados 100 question?rios, dentre os quais 60 deles utilizados para an?lise. A pesquisa mostrou por meio das an?lises, que a maneira de se incentivar as pessoas a lerem perpassa pelo modelo prim?rio de entendimento sobre a leitura ao qual os slogans se utilizaram, fazendo eles parte de um discurso dominante, que pouco ou nada contribuiu para o aumento do n?mero de leitores no pa?s. Atrav?s das an?lises dos slogans e da recep??o dos sujeitos da pesquisa, conseguimos perceber a heterogeneidade e a ideologia presente, revelando a todo instante, o entendimento da leitura como uma pr?tica superficial, n?o trazendo ? luz algumas de suas importantes fun??es dentro de um contexto educacional mais amplo

Foram tomadas amostras de aço líquido referentes a três grupos de aço, a saber: (I) aços baixo-carbono (0,02 %C 0,08), acalmados ao alumínio; (II) aços peritéticos (0,09 %C 0,15), acalmados ao alumínio e silício; (III) aços ultrabaixo carbono ( C<35 ppm), acalmados ao alumínio.Os aços foram produzidos em aciaria do tipo LD e foram, a seguir, tratados em equipamentos de refino secundário, adequados a cada um dos casos.As amostras forma colhidas no distribuidor de uma máquina de lingotamento contínuo de placas, segundo critério que minimiza a possibilidade da ocorrência de interferências que pudessem mascarar o resultado do tratamento de refino secundário tais como re-oxidação do aço e coleta simultânea de escória. As amostras foram submetidas à análise de inclusões utilizando-se técnicas de microscopia óptica, microscopia eletrônica e micro-análise. Foi possível caracterizar as inclusões presentes em cada tipo de aço segundo a morfologia, o tamanho, a quantidade e a composição química. / Non-metallic inclusions in liquid samples of (I) low-carbon aluminium killed steel (0,02wpct C 0,08wpct), (II) peritetic aluminium and silicon killed steel (0,09wpct C 0,15wpct); (III) extra-low-carbon, aluminium killed steel (C<35 ppm) were taken from the tundish distributor of a continuous casting caster for steel plates according to a procedure that minimizes re-oxidation of steel and/or pick up of liquid slag. The samples were inspected through the following microstructural techniques: optical microscopy, electronic microscopy, and electron microprobe. Were possible to feature present inclusion in each kind of steel according to morphology, size, amout and chemical composition.

In order to spell fluently and accurately, phonology, orthography, and morphology must be integrated and stored into long term memory (Berninger & Richards, in press; Berninger, Nagy, Tanimoto, Thompson, Abbott, 2015). Children with dysgraphia, dyslexia, and OWL-LD have specific deficits in linguistic processing that impede the cross-mapping of these linguistic elements. This study analyzes the frequency and nature of spelling errors produced by children with dysgraphia, dyslexia, and OWL-LD during an academic writing task in order to determine if known deficits in linguistic processing affect the type and severity of spelling errors made by these children. The present study analyzed error severity and frequency of spelling errors produced by children with dysgraphia (n=13), dyslexia (n=17), or OWL-LD (n=5) during the academic writing tasks obtained in the Berninger et al. (2015) study. In the previous study, students read or listened to computerized lessons about basic mathematical concepts and then typed summaries of what they learned. For the current study, all spelling errors made during the typed summary writing tasks were extracted and analyzed using the Phonological, Orthographic, Morphological Assessment of Spelling (POMAS) and then recoded with POMplexity (a measure of error severity) to determine the severity and frequency of spelling errors made in the linguistic categories of phonology, orthography, and morphology. Results indicated that the students did not differ in error severity by diagnostic category. However, a qualitative analysis using the POMAS revealed that children from different diagnostic categories produced different types of errors. With respect to error frequency, only students with dysgraphia made significantly fewer errors than students with OWL-LD, and all participants, regardless of diagnostic category produced more errors in typed summaries following the reading condition. These results are consistent with previous research indicating that children with learning disabilities do not produce deviant spelling errors when compared to typically-developing, age-matched peers or typically-developing, spelling-matched peers (Silliman, Bahr, and Peters, 2006, among others). The current results demonstrate that the spelling errors of children with learning disabilities reflect the expected linguistic breakdowns in cross-code mapping, and that children with learning disabilities may display these spelling deficits beyond an appropriate age.

Les souches de Legionella pneumophila sérogroupe 1 ST47 Lorraine sont actuellement responsables d'un nombre croissant de cas de légionelloses particulièrement dans le Nord de l'Europe. Cependant, elles ne sont retrouvées que très rarement dans l'environnement quand des investigations sont menées pour rechercher la source de cas de légionellose. Son environnement naturel reste donc méconnu. Notre objectif était donc d'étudier le phénomène de non détectabilité de la souche ST47 dans l'environnement. Nous avons observé que les traitements pré-analytiques (acidification, chauffage) pouvaient interférer avec les paramètres de culture pour certaines souches Lorraine environnementales, et que le milieu GVPC utilisé dans la norme NF T90-431 n'était pas recommandé pour la recherche des légionelles dans les prélèvements respiratoires, et donc potentiellement dans les prélèvements environnementaux. Ainsi, la PCR spécifique ST47, développée en collaboration avec l'équipe de Tim Harrison (Londres, Royaume-Uni), peut constituer un outil de détection intéressant dans les différentes matrices environnementales pour identifier les réservoirs de la souche. Nous avons cherché à cibler ces réservoirs. Nous avons montré, d'une part, que les robinets pouvaient être des réservoirs potentiels de légionelles. D'autre part, les données clinicoépidémiologiques et géographiques des souches Lorraine ST47 ont montré que les cas survenaient essentiellement hors institution (hôpital, maison de retraite) et principalement dans le quart Nord-Est du pays. L'amélioration des connaissances clinico-épidémiologiques et l'utilisation de la PCR spécifique ST47 devraient permettre, en s'affranchissant ou en améliorant les paramètres culturaux, d'identifier les réservoirs environnementaux de cette souche / The recently identified strains of Legionella pneumophila serogroup 1 belonging to Sequence Type (ST) 47 and pulsotype Lorraine are now responsible for an increasing number of Legionnaires’ disease (LD) cases mainly in the North of Europe. The major paradox is that ST47 strains are extremely rarely detected in environmental samples when investigations to identify the source of ST47 associated LD cases are undertaken. Thus its environmental habitat is unknown. The aim of our work was to study the non-detectability of this strain in environmental samples. Firstly, we have observed that pre-treatments (heat, acid) could interfere with recovery of an environmental ST47 Lorraine strain, and secondly, that GVPC medium imposed by the French standard NF T90-431, was not recommended for detection of Legionella spp. In clinical samples and potentially in environmental samples. Thus, to detect and identify ST47 Lorraine strains from clinical and ultimately, environmental samples in order to find the potential source of infection, we developed a strain specific realtime PCR method, in collaboration with Tim Harrison’s team (London, United Kingdom). We have also sought to target these sources. Then, we have shown that L. pneumophila could be detected in aerosols of a tap water. Moreover, epidemiologic French data have demonstrated that most of the LD cases associated with ST 47 strains occurred mainly in North East and were mainly community-acquired. Improved epidemiologic knowledge and the use of the strain specific real-time PCR should enable identification of environmental sources of ST47 Lorraine strain without culturing

No description available.

During the production of steel in the LD converter the refractory lining is exposed to high temperature emulsion of steel, slag and gas. It protects the steel body of the vessel to come in contact with the molten steel.The main purpose of this work was to observe the temperature distribution profile in converter refractory lining which is very important to understand the life of the refractory lining of the LD converter.In this study, a three dimensional (3D) heat transfer model for the refractory lining of converter was developed. The lining of the refractory material was considered as magnesite brick for inner lining, dolomite for intermediate lining and steel shell as outer part. In order to do the numerical modeling, the CFD software Ansys Fluent 13.0 was used. After considering the proper dimensions, meshing, properties of the lining material and boundary conditions, the modeling in Ansys was performed in two stages. In the first stage, the modeling was performed by assuming that the converter is already heated and the inside temperature of the furnace is 1923K and the outside temperature of the steel body is 300K. In the second stage, the temperature change of the molten steel, slag and the gas was considered as function of blowing time and slag height based on theories from different references. Firstly, the three dimensional (3D) heat transfer model was used for the refractory lining of the converter to show transient heat flow through the lining at different times. Secondly, 3D modeling results from fluent 13.0 was used to develop temperature distribution profile through the lining at different height for different time steps and at different positions with time and also along the converter height from the bottom to top. It has been noticed that refractories in the lining in contact with steel and slag must be of good quality for the reduction of wear cost and downtime and therefore the reduction of refractory cost per ton of steel production.