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Användning och Förståelse Av Extra Anpassningar : I relation till elever i läs- och skrivsvårigheter / The use and understanding of additional adaptations : - In relation to pupils with reading and writing difficultiesSachs, Elin January 2022 (has links)
Förväntat kunskapsbidragAtt öka kunskapen om hur lärare på mellan- och högstadiet använder extra anpassningar i relation till elever i läs- och skrivsvårigheter. Studien syftar även till att visa exempel på vilka extra anpassningar lärarna beskriver att de använder i den reguljära undervisningen samt att undersöka lärares uppfattningar om stöd från speciallärare. Syfte och frågeställningarSyftet med studien är att bidra med kunskap om hur några lärare beskriver användningen och förståelsen av extra anpassningar i relation till elever i läs- och skrivsvårigheter Syftet med studien är också att kartlägga vilka extra anpassningar lärarna beskriver att de använder i den reguljära undervisningen samt att undersöka lärares uppfattningar om stöd från speciallärare. Följande frågeställningar har formulerats utifrån studiens syfte:Hur beskriver lärarna sin förståelse/sina kunskaper och erfarenhet av extra anpassningar i relation till elever i läs- och skrivsvårigheter?På vilket sätt följer lärarna upp de extra anpassningarna i relation till elever i läs- och skrivsvårigheter?Vilket behov ser lärarna av stöd från specialläraren i arbetet med extra anpassningar i relation till elever i läs- och skrivsvårigheter? TeoriUtgångspunkten i studien är baserad på ett sociokulturellt perspektiv där Vygotskijs teori om människans utveckling och lärande i samspel med varandra ligger till grund. MetodEnkäten har bearbetats utifrån en tematisk ansats med fenomenografiskt inslag. Tematisk analys fokuserar på att lyfta fram språkliga drag t ex genom att plocka ut liknelser i det som används eller sägs samt hur ofta det används/sägs. Fokus ligger på att hitta teman i det insamlade datamaterialet för att sedan beskriva dem. ResultatResultatet av enkätundersökningen visar att samtliga lärare arbetar med extra anpassningar och att det i alla klasser finns elever i behov av särskilt stöd kopplat till läs- och skriv-svårigheter. Det framkommer att tillgången till extra anpassningar är varierad och omfattande i form av olika tekniska hjälpmedel, bild- och textstöd, struktur i lektionsinnehåll samt anpassat material. Det framkommer även att det inte räcker med att bara arbeta med generella anpassningar utan man behöver mer specifika anpassningar. Det räcker inte heller med att ge elever hjälpmedel (artefakter), de måste också förstå hur de ska använda dem för att det ska ge det stöd som behövs. Lärarna i undersökningen visar att stöd från speciallärare är viktigt men det saknas ofta möjligheter att optimalt utnyttja speciallärarens kompetens då tid saknas och tillgång till speciallärare saknas. Det framkommer även att det är brist på tid för planering och utveckling samt implementering av extra anpassningar. Specialpedagogiska implikationerResultatet visar på ett stort behov av ökad speciallärarkompetens så att lärare i den ordinarie undervisningen får de stöd och förutsättningar som krävs för att möta alla elever i klass-rummet. Specialläraren har således en viktig funktion i att göra lärarna medvetna om elevernas olika behov och hur lärarna kan stötta eleverna. Speciallärarens roll blir att skapa samsyn kring hur stödet kan ges i klassrummet och hur man skapar ett gemensamt förhållningssätt på skolan i mötet med elever i behov av särskilt stöd.
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Entrepreneurial orientation in dynamic environments: the moderating role of extra-organizational adviceAdomako, Samuel, Narteh, B., Danquah, Joseph K., Analoui, Farhad January 2016 (has links)
Yes / Purpose- Research on entrepreneurial orientation (EO) has concluded a positive link between
EO and firm performance and that relationship depends on several contingencies. The paper
derives insights from the absorptive capacity and contingency perspectives to introduce extraorganizational advice as a moderator of the relationship between EO and firm performance in a dynamic environment.
Design/methodology/approach-Using survey data from 340 small and medium-sized
enterprises (SMEs) in Ghana, the study examines the moderating influence of extraorganizational advice on the EO-firm performance relationship in dynamic environments.
Findings-The study’s empirical findings suggest that extra-organizational advice amplifies
the EO-performance relationship in dynamic environments.
Research limitations/implications-The cross-sectional design of the study does not permit
causal inferences to be made regarding the variables examined. Future studies may use
longitudinal design to examine the causal links of the variables. Limitations aside, the study
helps to answer how extra-organizational advice translates EO into improved performance in
an environment characterised by constant flux.
Practical implications- The results of this paper can assist entrepreneurs and policy-makers
in understanding the dynamics and processes involved in implementing a strategic orientation
to achieve higher performance. For SME managers, firm performance is determined by high
levels of EO and extra-organizational advice in dynamic environments. The understanding of
this issue can promote the development and maintenance of entrepreneurial ventures.
Originality/value-The paper examines an important, but under-researched issue-the
moderating effect of extra-organizational advice on the EO-performance relationship in
dynamic environments. To the best of the authors’ knowledge, the present study pioneers
research in this area.
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Lärares inställningar till inkludering i praktiken : En kvalitativ intervjustudie om inkludering i SO / Teachers’ attitudes towards inclusion in practiceAndersson, Linda, Wallström, Nicole January 2024 (has links)
Syftet med denna studie är att synliggöra hur lärare skapar en inkluderande so-undervisning som innebär att alla elever ges möjlighet att samspela och delta i undervisning utifrån deras egna förutsättningar. Den sociokulturella teorin och det kritiska perspektivet användes som ett par glasögon i de avslutande delarna av studien. För insamling av empiri användes semistrukturerade intervjuer med åtta legitimerade lärare. Anteckningar och inspelningar analyserades och kategoriserades utifrån teman. Resultaten av intervjuerna visar, för att åstadkomma en inkluderande undervisning, inte bara inom so-ämnena, krävs det att hela skolorganisationen intar ett inkluderande förhållningssätt. För att uppnå detta måste lärarna inneha en positiv inställning till inkludering samt att det bör finnas ett gott samarbete med både vuxna och barn. Olika anpassningar är av vikt för det inkluderande samspelet. Resultaten som framkommer genom intervjuerna och som belyses i de olika kategorierna pekar i riktning mot att lärarna strävar efter en skola för alla där undervisningen ska vara inkluderande, gynnsam och likvärdig. Studiens resultat visar på viktiga aspekter som spelar in för att en skola och dess lärare ska kunna inta ett inkluderande förhållningssätt.
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A constructively critical review of change and innovation-related concepts: towards conceptual and operational clarityPotocnik, K., Anderson, Neil 2016 April 1927 (has links)
Yes / The aim of this paper is to examine and clarify the nomological network of change and innovation (CI)-related constructs. A literature review in this field revealed a number of interrelated constructs that have emerged over the last decades. We examine several such constructs—innovation, creativity, proactive behaviours, job crafting, voice, taking charge, personal initiative, submitting suggestions, and extra-role behaviours. Our conceptual analysis suggests each one of these constructs represents a specific component of CI-related behaviours. However, we also found that on occasion these concepts have been dysfunctionally operationalized with evidence of three dysfunctional effects: (a) construct confusion, (b) construct drift, and (c) construct contamination. Challenges for future research to enhance conceptual and operational clarity are discussed. / The British Academy: [Grant number SG110409] awarded to the first author and by UK Leverhulme Trust: [Grant number IN-2012-095] awarded to the second author.
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Stimulation biochimique et biomécanique des fibroblastes ligamentairesDesRosiers, Éric A. January 1995 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
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Phenomenology of neutrino properties, unification, and Higgs couplings beyond the Standard ModelRiad, Stella January 2017 (has links)
The vast majority of experiments in particle physics can be described by the Standard Model of particle physics (SM). However, there are indications for physics beyond it. The only experimentally demonstrated problem of the model is the difficulty to describe neutrino masses and leptonic mixing. There is a plethora of models that try to describe these phenomena and this thesis investigates several possibilities for new models, both full theories and effective frameworks. The values of the parameters in a model are dependent on the energy scale and we say that the parameters run. The exact behavior of the running depends on the model and it provides a signature of the model. For a model defined at high energies it is necessary to run the parameters down to the electroweak scale in order to perform a comparison to the known values of observed quantities. In this thesis, we discuss renormalization group running in the context of extra dimensions and we provide an upper limit on the cutoff scale. We perform renormalization group running in two versions of a non-supersymmetric SO(10) model and we show that the SM parameters can be accommodated in both versions. In addition, we perform the running for the gauge couplings in a large set of radiative neutrino mass models and conclude that unification is possible in some of them. The Higgs boson provides new possibilities to study physics beyond the SM. Its properties have to be tested with extremely high precision before it could be established whether the particle is truly the SM Higgs boson or not. In this thesis, we perform Bayesian parameter inference and model comparison. For models where the magnitude of the Higgs couplings is varied, we show that the SM is favored in comparison to all other models. Furthermore, we discuss lepton flavor violating processes in the context of the Zee model. We find that these can be sizeable and close to the experimental limits. / <p>QC 20170221</p>
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Implication de CD146 soluble sur les capacités invasives des trophoblastes. : CD146 soluble et auto-anticorps anti-CD146 dans la sclérodermie. / Implication of CD146 in trophoblast invasiveness. : Soluble CD146 and auto-antibodies against CD146 in systemic sclerosis.Kaspi, Elise 17 December 2012 (has links)
CD146 est une glycoprotéine appartenant à la superfamille des immunoglobulines, exprimée de manière ubiquitaire sur l'endothélium, principalement au niveau des jonctions. Une forme soluble de CD146 (CD146s) est générée par clivage de la forme membranaire par un mécanisme dépendant des métalloprotéases. CD146 et CD146s interviennent dans le maintien de l'intégrité de l'endothélium, la transmigration endothéliale des monocytes et possèdent des propriétés angiogéniques. Les concentrations sériques de CD146s varient au cours de pathologies liées à une atteinte vasculaire. Notre travail a pour but d'étudier l'implication de CD146s dans deux contextes indépendants: la physiopathologie obstétricale et la sclérodermie systémique. La première partie de notre travail a consisté à analyser le rôle de la molécule au cours de la grossesse. Dans le placenta normal, l'expression de CD146 est restreinte aux trophoblastes possédant des capacités de migration et d'invasion, les trophoblastes extra-villeux (EVT). Ces EVT remodèlent les artères utérines spiralées afin d'établir une circulation foeto-maternelle. Au cours de ce processus, appelé pseudo-vasculogenèse, les EVT acquièrent un phénotype endothélial. De plus, l'expression placentaire de CD146 et les concentrations de CD146s varient au cours de grossesses pathologiques. L'hypothèse de notre travail est que CD146s régulerait les capacités invasives des EVT et interviendrait dans le développement placentaire. / CD146 is a member of the immunoglobulin superfamily. This is a membrane glycoprotein localized at the endothelial junction. CD146 also exists as a soluble form in the plasma (sCD146), generated by proteolysis of membrane CD146 through a mechanism involving metalloproteinases. CD146 and sCD146 are involved in endothelium integrity, monocyte transmigration and display angiogenic properties. CD146s level variations are observed in vascular pathologies. The aim of our work was to investigate the role of sCD146 in obstetrical physiopathology and in systemic sclerosis. In a first part, the involvement of our molecule was analyzed during pregnancy. In normal placenta, CD146 is expressed in intermediate and extra-villous trophoblasts (EVT), presenting migratory and invasive properties. EVT invade the spiral arteries and convert from an epithelial to an endothelial phenotype during the pseudo-vasculogenesis process. Moreover, CD146 placental expression and sCD146 levels are modified during pathologic pregnancies. We hypothesized that sCD146 could regulate EVT invasiveness and placental development. Using placental villous explants, we demonstrated that sCD146 inhibits EVT outgrowth. Consistently, we showed that sCD146 inhibits the ability of EVT cells (HTR8/SVneo) to migrate, invade and form tubes in Matrigel®. The involvement of sCD146 in human pregnancy was investigated by evaluation of sCD146 levels in 50 pregnant women. We observed physiological down-regulation of sCD146 throughout pregnancy. These results prompted us to investigate the effect of prolonged sCD146 administration in a rat model of pregnancy.
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Análises em larga escala de proteínas e construção de redes biológicas com foco em estudos de cromossomos BNakajima, Rafael Takahiro. January 2019 (has links)
Orientador: Cesar Martins / Resumo: Os cromossomos B ocorrem em cerca de 2.828 espécies de diferentes táxons, sendo basicamente heterocromáticos e compostos de DNAs repetitivos. Recentemente, análises genômicas em larga escala estão sendo utilizadas para elucidar questões acerca dos cromossomos supranumerários. Os peixes ciclídeos recebem grande interesse científico, uma vez que muitas espécies passaram por um rápido e extenso processo de radiação adaptativa. Em algumas espécies do grupo, como Astatotilapia latifasciata, foi descrita a presença de cromossomos B. Neste trabalho foi caracterizado o perfil de expressão proteico em tecidos específicos na A. latifasciata e realizada análise funcional da presença do cromossomo B nesta espécie de teleósteo, elucidando a influência que este pode acarretar em vias metabólicas específicas. Além disso, esses dados foram integrados com os resultados de RNA-Seq dessa espécie, e construídas sub redes de co-expressão e interação proteína-proteína. Também foi calculada a entropia de Shannon, a qual não apresentou diversidade na expressão dos transcritos em cada biblioteca comparada. Além disso, foi analisada a expressão diferencial de RNAm em cada tecido em relação a presença do cromossomo B e ao sexo. Dentre os transcritos diferencialmente expressos, a análise de enriquecimento funcional apresentou processos relacionados ao ciclo celular, resposta imune e resposta ao estresse. Na maioria dos casos analisados entre a expressão de proteínas, os transcritos up regulated e as sub... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The B chromosomes occur in about 2,828 species of different taxa, being heterochromatic and composed of repetitive DNA.Recently, large-scale genomic analyzes are being used to elucidate questions about supernumerary chromosomes.Cichlid fish are of great scientific interest, since many species have gone through a rapid and extensive process of adaptive radiation.In some species of the group, such as Astatotilapia latifasciata, the presence of B chromosomes was described.In this work, we characterize the profile of protein expression in specific tissues in A. latifasciata and performed a functional analysis of the presence of the B chromosome in this species of teleost, elucidating the influence that it can cause in specific metabolic pathways.In addition, we integrate these data with the RNA-Seq results of this species, and construct sub-networks of co-expression and protein-protein interaction.The Shannon entropy was also calculated, which did not show diversity in the expression of the transcripts in each library. In addition, differential expression analysis was performed on each tissue separately and the relationship between the presence of B chromosome and sex chromosome was analyzed. Among the differentially expressed transcripts, functional enrichment analysis presented processes related to the cell cycle, immune response and stress response. In relation to abundance of proteins, the up regulated transcripts and the sub-networks we identified genes like the Aurora kinas... (Complete abstract click electronic access below) / Doutor
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Caracteriza??o molecular (RAPD) e an?lise das prote?nas de reserva em gr?os de variedades locais de arroz do Maranh?o / Molecular characterization (SSR and RAPD) and analysis of storage proteins in grains of local varieties of rice of the Maranh?oARA?JO, Elisangela Sousa de 23 February 2006 (has links)
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Previous issue date: 2006-02-23 / FAPERJ / CAPES / Brazil is the country with the greatest plant genetic diversity in the world with the potential still underestimated what makes it necessary to characterize local genetic material. Genetic resources are studie in several stages and identify traits of agronomic value in hardy varieties is one of the roles of gene banks (BAG's). In rice, because it is a very important crop for the diet of the brazilian population, selecting genotypes with high yield, nutritional value and adapted to the most diverse environmental conditions is a continuous search for improvement programs. In this sense, the present study aimed to adapt methodologies for protein extraction reserve and DNA of rice seeds to be used in routine laboratory for characterization of germplasm banks. After optimization of methodologies, seeds of twenty local varieties of rice grown in the state of Maranh?o different times (Experiment I: Aug-2002 to Mar-2003 and Experiment II: Nov-2002 to Jun-2003) were analyzed for study of diversity genetic (DNA and protein) and seasonality effect on its accumulation of reserves and gross protein. The analysis of variance or protein content and protein fractions was highly significant (P <0.01) between genotypes and experiments. The mean protein fractions albumin+globulin and glutelin were higher in experiment I, whose average temperatures were 330C while the average gross protein (CP) was higher than in Experiment II in which the average temperature was 410C.Varieties analyzed, the Pingo d? ?gua (220019) and Jatob? (220012) showed the highest values for PB (11.32 and 11.13%) and glutelin (83.73 and 92.86 mg flour). The molecular characterization by RAPD was based on 37 polymorphic band sand phylogenetic analysis revealed a genetic diversity at 50% training with four groups and three separate varieties. Groups based on the varieties named Lageado and Zebu branco seems to have been the shape of the grains and reason C/L. / O Brasil ? o pa?s com a maior diversidade gen?tica vegetal do mundo com potencial ainda subestimado o que torna fundamental a caracteriza??o do material gen?tico local. Os recursos gen?ticos s?o estudados em v?rias etapas e identificar caracter?sticas de valor agron?mico em variedades r?sticas ? um dos pap?is dos bancos de germoplasma (BAG?s). Em arroz, por se tratar de uma cultura muito relevante para a dieta da popula??o brasileira, selecionar gen?tipos com alta produtividade, valor nutricional e adaptados ?s mais diversificadas condi??es ambientais ? uma busca cont?nua em programas de melhoramento. Nesse sentido, o presente trabalho teve por objetivos adaptar metodologias para extra??o de prote?na de reserva e de DNA de sementes de arroz a fim de serem empregadas na rotina de laborat?rio para caracteriza??o de bancos de germoplasma. Ap?s otimiza??o das metodologias, sementes de vinte variedades locais de arroz do Estado do Maranh?o cultivadas em ?pocas distintas (Experimento I: Ago-2002 a Mar-2003 e Experimento II: Nov-2002 Jun-2003) foram analisadas para fins de estudo de diversidade gen?tica (DNA e prote?na) e efeito da sazonalidade em seu ac?mulo de prote?na bruta e reserva. A an?lise de vari?ncia para teor de prote?na e fra??es proteicas foi altamente significativa (P<0,01) entre os gen?tipos, e os experimentos. As m?dias das fra??es proteicas albumina+globulina e glutelina foram superiores no experimento I, cujas temperaturas m?dias foram de 330C enquanto que a m?dia da prote?na bruta (PB) foi superior no Experimento II em que a m?dia de temperatura foi de 410C. Das variedades analisadas, a Pingo d??gua (220019) e Jatob? (220012) foram as que apresentaram os maiores valores para PB (11,32 e 11,13%) e glutelina (83,73 e 92,86 mg.g farinha). A caracteriza??o molecular pela RAPD foi baseada em 37 bandas polim?rficas e a an?lise filogen?tica revelou uma diversidade gen?tica em 50% com forma??o de quatro grupos e tr?s variedades isoladas. Os grupos formados pelas variedades de nome Lageado e Zebu branco parecem ter sido pela forma dos gr?os e raz?o C/L.
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Systèmes intégrables non commutatifs et la correspondance Ads/CFT en cosmologie.Mazzanti, Liuba 27 July 2007 (has links) (PDF)
Ma these se deroule suivant deux principales lignes de recherche. Les deux arguments traites constituent une relation entre la theorie des cordes et les aspects phenomenologiques/cosmologiques. D'une part, la geometrie noncommutative (NC) est une consequence naturelle de la presence de branes et flux dans la theorie des cordes. La non commutativite deforme certaines proprietes fondamentales des theories ordinaires decrivant par exemple les interactions electro–faibles et fortes ou les modeles statistiques. C'est dans ce sens que la geometrie NC represente une application a la phenomenologie des cordes. D'autre part, les branes sont l'ingredient clé des modeles d'univers branaires. Le modele de Randall–Sundrum (RS) en particulier offre de nouvelles perspectives tant du point de vue de la cosmologie, ouvrant des scenarios d'evolution cosmologique non conventionnelle, que du point de vue de l'holographie. La premiere partie de la these est dediee a la geometrie NC et, en particulier, aux theories de champs NC integrables. Le but principal du travail a ete d'etudier les consequences de la non commutativit´e par rapport a l'integrabilite. Plus precisement, on a voulu verifier ou refuter dans un contexte NC le theoreme qui lie, en deux dimensions, l'integrabilite a la factorisation de la matrice S. Avec integrabilite on parle de l'existence d'un nombre infini de courants locaux conserves, associes aux symetries de la theorie de champs.Le point de depart a donc ete de garantir la presence de tels courants, au moyen du formalisme du bicomplexe. Cette methode permet d'obtenir les equations du mouvement en tant que conditions d'int´ egrabilite d'un systeme d'equations differentielles lineaires. a partir des solutions du meme systeme lineaire suivent les courants conserves. En exploitant le formalisme de Weyl, la procedure est immediatement generalisable a la geometrie NC. Une algebre de fonctions (operateurs de Weyl) definie sur un espace NC est associee a une algebre NC de fonctions ou la multiplication est executee au moyen d'un produit NC de Moyal: le produit. En introduisant le produit au niveau du systeme lineaire et en en deduisant les equations du mouvement NC, on obtient la generalisation NC du bicomplexe. On a infere le premier modele en generalisant le bicomplexe du modeledesine–Gordon(SG)a la geometrie NC. Nous avons deduit (en collaboration avec Grisaru, Penati, Tamassia) l'action correspondante aux equations du mouvement precedemment etablies par Grisaru et Penati. Le calcul des amplitudes de diffusion et production a determine les caracteristiques de la matrice S du modele. Des comportements acausaux ont ete releves pour les processus de diffusion. En outre, les processus de production possedent une amplitudes non nulle: d'ou la non validite du theoreme d'integrabilite vs. factorisation pour cette version NC du modele de SG. D'autres proprietes ont ete mises en evidence, comme la relation avec la theorie des cordes et la bosonisation. Le deuxieme modele de SG NC a ete propose en collaboration avec Lechtenfeld, Penati, Popov, Tamassia. Les equations du mouvement ont ete tirees de la reduction dimensionnelle du modele sigma NC en 2+1 dimensions, qui a son tour est la reduction de la theorie de self–dual Yang–Mills NC en 2+2 dimensions (decrivant les supercordes N =2avecchamps B). L'action a ete calculee de meme que les amplitudes. Les processus de production possedant des amplitudes nulles et ceux de diffusion ne dependant pas du parametre de NC, entraınent ainsi un comportement causal. Le deuxieme modele de SG NC semble donc obeir a l'equivalence entre integrabilite et factorisation de la matrice S. La reduction de la theorie des cordes garde sa validite meme au niveau de l'action contrairement au modele precedent. La deuxieme partie de ma these traite des modeles d'univers branaires, ou plus precisement des modeles de RS. Le modele propose par Randall et Sundrumse situe dans un bulk 5–dimensionnel, caracterise per une symetrie d'orbifold Z2 par rapport `a la position de la brane 4–dimensionnelle. Grace au facteur de warp qui multiplie le sous–espace 4–dimensionnel parallele a la brane, on obtient la localisation des modes du graviton. Par consequent, le potentiel gravitationnel efficace est newtonien aux energies inferieures a la masse de Planck. En introduisant en outre un terme de matiere dans le bulk et en considerant l'echange d'energie entre brane et bulk, une variete de nouvelles cosmologies en derive. Dans la premiere partie de mon travail sur RS nous avons propose un modele analogue situe dans un bulk 7–dimensionnel. La brane 6–dimensionnelle — ayant compactifie deux dimensions — est placee au point fixe de l'orbifold Z2. Afin d'etudier l'evolution cosmologique en nous mettant en relation avec les observations, nous avons introduit l'echange d'energie entre brane et bulk. Les scenarios possibles sont nombreux et dependent de la forme explicite du parametre d'echange d'energie. Entre autres, les points fixes possedent une acceleration positive, pouvant ainsi representer la recente acceleration de l'univers. Il sont egalement stables pour un large ensemble des valeurs des parametres. Finalement, on peut tracer des scenarios qui partent d'une phase initiale acceleree, en passant successivement a une ere de deceleration, pour terminer sur un point fixe stable d'inflation. Les modeles d'univers branaires a la RS possedent un dual holographique via AdS/CFT. La correspondance AdS/CFT etablit qu'une theorie de supergravite(ou,plusg´ en´ eralement, de cordes) dans un champ de fond d'anti de Sitter (AdS) en d + 1 dimensions est duale a une theorie de champs conforme (CFT) en d dimensions. Tenant compte des divergences presentes dans les deux descriptions, cette correspondance a ete rendue plus precise par la formulation de la renormalisation holographique. Si l'espace de AdS est regularise au moyen d'un cutoff infrarouge, la correspondante CFT resulte regularisee par un cutoff ultraviolet et couplee a la gravite d–dimensionnelle. En analogie a l'analyse effectuee en cinq dimensions par Kiritsis, nous avons construit la theorie duale au modele cosmologique de RS en sept dimensions. Pour capturer les dynamiques dictees par l'echange d'energie entre brane et bulk, la theorie holographique en six dimensions a ete generalisee au cas interagissant (entre matiere et CFT) et non conforme. Le resultat sont les relations entre les parametres de masse appartenant aux deux descriptions et entre l'echange d'energie, d'un cote, et le parametre d'interaction, de l'autre. De plus, le parametre de rupture conforme est associe au parametre d'auto–interaction du bulk dans la description de supergravite 7–dimensionnelle. Le travail de recherche inclut donc des resultats pouvant trouver leur application dans la phenomenologie et cosmologie des cordes. D'une part on a enqueter sur l'influence de la noncommutativite liee a l'integrabilite du modele de SG. D'autre part, les consequences cosmologiques de l'emplacement du modele de RS en sept dimensions ont ete etudiees et la correspondance AdS/CFT a ete appliquee afin d'en tirer des informations sur la theorie duale, couplee a la gravite.
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