Dissertationen: „DiCre“

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Loubens, Manon. „Analyse fonctionnelle de protéines des organites apicaux chez les sporozoïtes de Plasmodium“. Electronic Thesis or Diss., Sorbonne université, 2021. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2021SORUS245.pdf.

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L’infection par Plasmodium, parasite responsable du paludisme, débute par l’inoculation de sporozoïtes invasifs par un moustique Anopheles femelle. Les sporozoïtes infectent des cellules du foie pour s’y développer en mérozoïtes qui une fois libérés dans la circulation sanguine vont se développer dans les érythrocytes. L’invasion des cellules implique la sécrétion d’organites apicaux (micronèmes et rhoptries) et la formation d’une structure particulière (jonction mobile) conduisant à l’internalisation du parasite au sein d’une vacuole parasitophore. Les mécanismes moléculaires impliqués dans l’invasion des hépatocytes par les sporozoïtes restent méconnus. Les organites sécrétoires apicaux contiennent des protéines spécifiquement exprimées chez le sporozoïte (dont des protéines à domaine 6-cystéines), et des protéines également exprimées chez les mérozoïtes (comme AMA1, les RONs ou CLAMP) impliquées dans la formation de la jonction mobile. Nos travaux ont révélé le rôle essentiel d’une protéine à domaine 6-cystéines, B9, dans l’invasion des hépatocytes par les sporozoïtes. L’utilisation d’une stratégie de mutagénèse conditionnelle a permis de démontrer le rôle d’AMA1, RON2, RON4 et CLAMP chez les sporozoïtes, pour l’invasion des hépatocytes chez l’hôte mammifère mais également pour la colonisation des glandes salivaires du moustique. Nos résultats confortent l’hypothèse d’une compartimentation fonctionnelle des protéines micronémales chez les sporozoïtes. Ce travail contribue à une meilleure compréhension des mécanismes moléculaires mis en jeu lors de l’invasion des hépatocytes et identifie de nouvelles cibles potentielles pour bloquer l’invasion du foie par Plasmodium
Infection with Plasmodium, the parasite responsible for malaria, begins with the inoculation of invasive sporozoites by a female Anopheles mosquito. Sporozoites infect liver cells and develop into merozoites which, once released into the bloodstream, undergo asexual multiplication cycles in red blood cells. Host cell invasion involves the secretion of apical organelles (micronemes and rhoptries) and the formation of a unique structure (moving junction) that leads to the internalization of the parasite within a parasitophorous vacuole. However, the molecular mechanisms involved during invasion of hepatocytes by sporozoites remain unknown. Apical secretory organelles contain proteins specifically expressed in sporozoites (including 6-cysteine domain proteins), and proteins also expressed in merozoites (such as AMA1, RONs or CLAMP), which are involved in the formation of the moving junction. Our work revealed the essential role of a 6-cysteine domain protein, B9, in the invasion of hepatocytes by sporozoites. Using a conditional mutagenesis strategy, we also demonstrated the role of AMA1, RON2, RON4 and CLAMP in sporozoites, not only for hepatocyte invasion in the mammalian host but also for salivary gland colonization in the mosquito. Our results support the hypothesis of a functional compartmentalization of microneme proteins in Plasmodium sporozoites. This work contributes to a better understanding of the molecular mechanisms involved during infection of hepatocytes and identifies new potential targets to block malaria liver infection

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Frohnecke, Nora. „Funktionelle Charakterisierung des Ferredoxin Redoxsystems von Toxoplasma gondii“. Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19075.

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Toxoplasmose ist weltweit eine der am häufigsten auftretenden parasitären Zoonosen mit einer geschätzten Infektionsrate von über 30%. Toxoplasma gondii (Phylum: Apicomplexa) besitzt ein Plastid ähnliches Organell, den Apicoplasten. In diesem befindet sich das einzig bekannte Redoxsystem, welches aus der Ferredoxin-NADP+-Reduktase und Ferredoxin (Fd) besteht. Fd als Elektonendonator liefert Elektronen an verschiedene essentielle Stoffwechselwege, wie der Isoprenoidvorstufen- und Liponsäuresynthese. Um die bei einem Elektronentransfer benötigte direkte Protein-Protein-Interaktion eingehend zu analysieren, wurde ein bakterielles Reverse Two Hybrid System verwendet, womit die Interaktion von TgFd und TgLipA gezeigt werden konnte. Da angenommen wird, dass Fd eine zentrale Rolle in verschiedenen Stoffwechselwegen übernimmt, ist für einen Fd Knockout ein komplexer biochemischer Phänotyp zu erwarten, der möglicherweise zum Absterben der Parasiten führt. Zur Untersuchung dessen wurden zwei komplementäre Wege verfolgt. Eine der Strategien basierte auf dem grundsätzlichen Nachweis, dass Fd unerlässlich für das Überleben von T. gondii ist. Mit Hilfe des DiCre Systems sollte ein definierter genetischer Fd Knockout hergestellt werden, welcher jedoch nicht zweifelsfrei generiert werden konnte. Bei der zweiten Strategie kam ein konditionales Knockdown System zur Anwendung, bei welchem die Expression des Fd Gens nach Induktion herabreguliert wird. Mit Hilfe dessen konnten weitreichende Auswirkungen der Fd Defizienz auf T. gondii gezeigt werden: die Fettsäuresynthese der im Apicoplasten synthetisierten Fettsäuren ist reduziert sowie die Motilität durch eine beeinträchtigte Isoprenoidsynthese verringert, wodurch insgesamt drastische Auswirkungen auf das Parasitenwachstum gezeigt werden konnten. Beide Stoffwechsel sind vom Elektronendonator Fd abhängig und durch die Fd Herabregulation betroffen. Die Ergebnisse unterstreichen die essentielle Rolle des Fd-Redoxsystems von T. gondii.
Toxoplasmosis is one of the most common parasitic zoonoses world-wide, around 30% of human beings are infected. Toxoplasma gondii (phylum: Apicomplexa) contains a unique intracellular organelle derived from plastids, called apicoplast. The only known redox system in the apicoplast consists of the ferredoxin NADP+-reductase and its redox partner, ferredoxin (Fd). The latter donates electrons to different essential metabolic pathways in the apicoplast like the last two enzymes of the isoprenoid precursor biosynthesis and the lipoic acid synthesis. To dissect protein protein interactions for an electron transfer a bacterial reverse two hybrid system was used. The physical interaction of both proteins TgFd and TgLipA could be shown. Fd is supposed to play an important role in diverse metabolic pathways, hence a knock-out of the Fd gene is expected to generate a complex biochemical phenotype and be lethal to the parasite. Therefore two complementary approaches were used to analyze the role of TgFd in this context. The first strategy shall verify the essentiality of TgFd for the survival of T. gondii. It is based on the DiCre system whereby a defined genetic knock out of TgFd is produced. Respectives parasites have been generated, but at the end no genetic Fd knock out could be produced. In the second approach a conditional knock-down was generated, where the expression of the TgFd gene is repressed after induction. The Fd deficiency has wide ranging effects on T. gondii: The fatty acid synthesis of the apicoplast-synthesized fatty acids is reduced as well as the motility is decreased due to an affected isoprenoid synthesis. In total this leads to a dramatic inhibition of parasite growth. Both metabolic pathways depend upon the electron carrier Fd and thus are affected by Fd deficiency. The results underline the essential role of the ferredoxin redoxsystem of T. gondii.

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Holden, Damien James. „Generalised Brans-Dicke cosmology“. Thesis, University of Portsmouth, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247071.

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4

Coirault-Neuburger, Sylvie. „Dire la croyance“. Paris 5, 1994. http://www.theses.fr/1994PA05H094.

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Qu’est-ce-que croire ? Croire n'est ni savoir, ni simplement imaginer. Croire se dit de manière à développer un monde de relations originales. Le dialogue n'y est pas toujours facile. La logique y admet l'impossible. Les signes et les paroles qui expriment la croyance sont-ils dignes de foi ? Les relations avec l'autre, avec l'objet de croyance, exigent le parcours de chemins conduisant de la rencontre à la reconnaissance
What is believing? Believing is neither knowing, nor plain imagination. One’s belief expresses itself so as to develop a world of original relations. Dialogue is not always possible there. Its logics admit impossible. Are signs and speeches that express belief faithful? Relations with other people, with the object of belief demand to go on ways leading from meeting to recognition

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Thibau, Tereza Cristina Sorice Baracho. „A legitimação ativa nas ações coletivas: um contributo para o estudo da substituição processual“. Universidade Federal de Minas Gerais, 2003. http://hdl.handle.net/1843/DIRE-5SFJMX.

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The objective of this doctoral thesis is to analyze all possible ways in interpreting the present-days Brazilian National Law, which assignment is to promote protection of the third generation new rights or interests, called trans individual, that has been risen to the fundamental warranties category. The Judicial Process Law discussions imposed by mass conflicts that are seen nowadays as globalization phenomena reflex, collectivism and popularization trend, imposed on social relationships, lead us to believe in the public law privatization and in the private law publicizing. This situation was analyzed focusing, first, the traditional juridical doctrine, and afterwards new items in order to adequate it to the needs ofthe present-day law. Taking that into account, it became necessary to exam the active legitimating ofthe intermediate figures to which the law has pointed as representative of the groups in Court. As part (ideological author) in the collective juridical process, the intermediating figures will be affected by all rights and obligations, applied by the process conditions. It would also be possible to imagine these representatives as process substitutes ofcollectivism (extraordinary legitimating). The juridical nature of active legitimating of these intermediating figures is subject to further discussion; there are tendencies of the doctrine to discriminate it according to the sort of trans individual interest that is needed to protect (diffuse, collective or homogeneous individual). It is believed that this juridical nature is of a collective institutional legitimating as a tertium gemus, which is characterized by presenting traces of collective, extraordinary and ordinary legitimating, simultaneously. Furthermore, considering that there is more than one legitimated figure to act in Court in the name of the collectivity, this legitimating will be equal in rights to act and also disjunctive. Besides the legitimating to juridical act, it should be examined the level of interest that the representatives need to demonstrate in order to meet the conditions to exercise their rights. This juridical process interest is measured by political adequate choice made by the Law to indicate the General Attorney's Office, the public figures, the entities of direct and indirect public administration departments, and associations (unions), as collectivity representatives. This choice was based both in the social importance of the juridical properties guarded in collective actions, and also in the potentiality and capacity ofperforming that those figures might have in this subject field. Examining the juridical proceedings that comprise the acfive legitimating and the intermediating figures interest in performing, besides the object and the effects of the judged matter in the collective actions, it should be verified that there is no perfect adequacy of the processing substitution intrinsic to the position hold by those intermediating figures in the juridical process. However, it cannot be denied that there are also similarities between the juridical institute of the process substitution and the condition of the collective institutional representative of those mentioned before. The juridical process law itself, as it is, does not make it easy to be safely interpreted in this subject area. Nevertheless, what can be seen is that there was a change, by juridical fiction, in the "part" concept, being considered "part" the one that was legitimated to propose the juridical action, and that fact became essential for the processing law being able to comprise collective conflicts. On the other hand, there is within the Brazilian Law, an integrated system that protects the trans individual rights and interests represented, essentially, by people, public civil and collective actions of the Costumer Defense Code, which satisfies the access of these individual rights and interests to the Justice. It cannot be forgotten the individual means that is always opened and upon which, the use of collective means will not lead to a pending juridical action. It is necessary that the people who deal directly with Laws obey this integrated system to avoid deviations and mistakes related to the relevance that the theme deserves, although, this theme conti
O trabalho visa a analisar os possíveis caminhos a serem traçados na interpretação do Direito nacional contemporâneo, que vem se empenhando na tarefa de promover a proteção dos novos direitos ou interesses de terceira geração, denominados metaindividuais, os quais forma elevados à categoria de garantias findamentais. As discussões jurídico-processuais impostas pelos conflitos de massa que hoje se verificam como reflexo dos fenômenos da globalização, coletivização e massificação imprimidas nas relações sociais, levam a pensar na privatização do direito público e na publicização do direito privado. Buscou-se então uma análise desta situação, focalizando inicialmente a doutrina jurídica tradicional, e posteriormente os novos enfoques que precisam ser a esta dirigidos, para adequá-las às necessidades do direito atual. Dentro deste panorama, surgiu a necessidade de se examinar a legitimação ativa dos entes intermediários, aos quais a lei conferiu a tarefa de representação das coletividades em juízo. Assumindo a posição de parte (autor ideológico) no processo coletivo, os entes intermediários estão afetados por todos os direitos e deveres que tal condição processual lhes destina. E, em princípio, poder-se-ia imaginar para estes a condição também de substitutos processuais (legitimação extraordinária) da coletividade. A natureza jurídica da legitimação ativa destes entes é matéria que ainda está em construção; há tendência da doutrina em diferenciá-la conforme a espécie de interesse metaindividual que se visa a proteger (difuso, coletivo ou individual homogêneo). Acredita-se que tal natureza é de ligitimação institucional coletiva, como um terium genus, a qual se caracteriza por apresentar traços da legitimação ordinária, extraordinária e coletiva, simultaneamente. E, visto que há mais de um ente legitimado a atuar em juízo em nome da coletividade, esta legitimação será também concorrente e disjuntiva. Além da legitimação para agir, examina-se o grau de interesse para agir, que tais entes precisam demonstrar, para que estejam completas as condições para o exercício do direito de ação destes. Tal interesse processual é medido pela adequação da escolha política que a lei fez ao indicar o Ministério Público, os entes públicos, as entidades e órgãos da administração pública direta ou indireta, e as associações (sidicatos), como representantes da coletividade. Esta escolha fundou-se tanto na relevância social dos bens jurídicos tutelados nas ações coletivas, como na força e capacidade de atuação que tais corpos podem significar nesta seara. Partindo-se do exame das circunstâncias processuais que cercam a legitimação ativa e o interesse de agir dos entes intermediários, além do objeto e dos efeitos da coisa julgada nas ações coletivas, verifica-se que não existe uma perfeita adequação da figura da substituição processual como inerente à posição ocupada no processo por tais entes. Todavia, não se pode negar que também existam semelhanças entre a figura do substituto processual e a condição de 'representante' institucional da coletividade àqueles referentes. A própria lei processual, assim como está, não facilita interpretações muito seguras neste campo. Entretanto, o que se verifica de concreto é que houve uma modificação, por ficção jurídica, no conceito de 'parte', passando a ser concebido como aquele que foi legitimado a intentar a ação, e tal fato tornou-se indispensável para que o direito processual pudesse acobertar os conflitos coletivos. Por outro lado, existe no direito brasileiro um sistema integrado de defesa dos direitos e interesses metaindividuais representado essencialmente pela ação popular, ação civil pública e ações coletivas do Código de Defesa do Consumidor, que garantem satisfatóriamente o acesso destes à justiça. Sem se esquecer da via individual que se mantém aberta e sobre a qual, o uso da via coletiva não induzirá litispendência. É necessário que os operadores do direito obedeçam a tal sistema, para evitar que ocorram desvios e enganos em relação à relevância que o tema merece, embora, quanto a este, continue palpitante e aberta as discussões doutrinárias e legislativas.

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Roberto, Giordano Bruno Soares. „O Direito Civil nas Academias Jurídicas do Império“. Universidade Federal de Minas Gerais, 2008. http://hdl.handle.net/1843/DIRE-7PYKYE.

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The following work intends to analyse how the teaching and literature production of private law took place in the law academies of the Empire. First of all it offers information about the foundation of law schools in Brazil. Then, it indicates the main data about the carrier and production of the professors who occupied the private law chairs in the first two Schools. Last of all, it takes into consideration the quality and effectualness both of the teaching as well as of the bibliographical issue of private law in the above place and period.
O presente trabalho pretende analisar o modo como se deram o ensino e a produção bibliográfica de direito civil nas Academias Jurídicas do Império. Inicialmente, oferece informações sobre a fundação dos cursos jurídicos no Brasil. Em seguida, indica os principais dados sobre a carreira e a produção bibliográfica dos professores que ocuparam as cátedras destinadas à matéria em ambas as Escolas. Por fim, proporciona reflexões sobre qualidade e relevância tanto do ensino quanto da produção bibliográfica de direito civil nos espaços e no período anteriormente indicados.

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Faria, Juliana Cordeiro de. „Seguro facultativo de responsabilidade civil: a problemática do direito de ação da vítima contra a seguradora na perspectiva do código civil de 2002“. Universidade Federal de Minas Gerais, 2004. http://hdl.handle.net/1843/DIRE-6APTKV.

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Na elaboração da presente tese visando a obtenção do título de doutor, para fins metodológicos, considerou-se importante redigir uma introdução com o intuito de demostrar a originalidade do seu propósito. A importância resulta do fato de que, no direito brasileiro muito já se escreveu acerca do problema admissibilidade do exercício do direito de ação pela vítima diretamente contra a seguradora visando o ressarcimento dos danos provocados pelo segurado, nos contratos de seguro facultativo de responsabilidade civil. A circunstancia de já existir literatura a respeito do tema poderia provocar dúvida quanto ao preenchimento pelo presente trabalho do requisito da originalidade, essencial a sua qualificação como tese de doutoramento. A tese não deveria veicular um tema original, isto é, totalmente novo? Como então considerar-se original a escolha de um tema que já foi anteriormente explorado pela comunidade científica na área do direito? A dúvida não tem, todavia, sua razão de ser se resgatado o verdadeiro sentido da originalidade e do propósito de uma tese. E ainda,se for considerado em específico os objetivos buscados com o presente estudo e a metodologia adotada no tratamento do tema.

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Hertz, Géraldine. „Dire Dieu, le dire de Dieu chez Philon, Plutarque et «Basilide»“. Thesis, Paris Est, 2013. http://www.theses.fr/2013PEST0015.

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Peut-on dire Dieu ? Dieu lui-même parle-t-il et se dit-il ? Les deuxquestions semblent intimement liées : si le langage est tenu pour une réalité étrangèreà la nature divine, il est en effet susceptible d’être jugé inapte à son expression. Cettethèse est consacrée à l’exploration d’une question qui a rencontré un intérêt sansprécédent dans le platonisme des débuts de l’époque impériale : celle de l’articulationentre le discours (λόγος) et le divin (θεός). Le signe le plus évident de cet intérêtnouveau pour la question du rapport entre discursivité et divinité est l’essor queconnaît alors le motif du « dieu ineffable » (θεὸς ἄρρητος). Les trois auteurs surlesquels porte cette étude – Philon, Plutarque et l’auteur présenté dans l’Élenchos(VII, 14-27, X, 14) comme « Basilide » – se caractérisent par une commune adhésionà l’idée que Dieu échappe à l’appréhension verbale, mais cette idée est loin des’exprimer chez eux de façon uniforme : si Plutarque semble réticent à déclarer Dieu« ineffable », Philon, lui, le reconnaît tel avec insistance, tandis que « Basilide »,considérant que le dire « ineffable » revient encore à en dire quelque chose,surenchérit en le déclarant « pas même ineffable ». Pour comprendre ces divergences,il s’agira d’examiner les données ontologiques, gnoséologiques et linguistiques quiexpliquent les positions respectives de ces auteurs sur la question de l’expression dudivin. Cette enquête débutera par un chapitre préliminaire où l’on situera dans soncontexte – celui du médioplatonisme – le débat sur le divorce entre λόγος et θεός etoù l’on en recherchera les prémisses chez Platon, Aristote et dans la spéculationpythagorisante
Can one make statements about God ? Does God speak and does hemake statements about himself ? These two questions are intimately related: iflanguage is taken to be a reality extraneous to God’s nature, it might be consideredunsuitable for expression of his nature. This dissertation explores the question of thearticulation between discourse (λόγος) and the divine (θεός) that became a prominentlocus of debate in early imperial Platonism. The clearest sign of this new-foundinterest in the relationship between discursivity and divinity is the growth in the motifof “ineffable God” (θεὸς ἄρρητος). The study looks at three authors – Philo,Plutarch, and the author presented in the Elenchos (VII, 14-27, X, 14) as “Basilides” –linked by a common adherence to the idea that God escapes verbal apprehension.Their respective way of expressing this idea is by no means uniform, however : ifPlutarch seems reticent to declare God “ineffable”, Philo declares this moreemphatically; “Basilides”, meanwhile, reckoning that declaring God “ineffable” isstill saying something about him, goes even further by declaring him “not evenineffable”. In order to understand these differences we must examine the ontological,gnoseological, and linguistic facts that explain the respective positions of theseauthors on the expression of the divine. This inquiry starts with a preliminary chapterwhich situates the debate about the gulf between discourse and God in its context –Middle Platonism – and seeks its premises in the thinking of Plato, Aristotle andPythagoreanizing speculation

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Klinder, Jens Simon [Verfasser]. „Vom dynamischen Phasenübergang im offenen Dicke Modell zum Dicke-Hubbard Modell / Jens Simon Klinder“. München : Verlag Dr. Hut, 2016. http://d-nb.info/1084386984/34.

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Cuellar, Trinna Lee. „The role of Dicer in post-mitotic dopaminoceptive neurons and turnover of Dicer generated microRNAs“. Diss., Search in ProQuest Dissertations & Theses. UC Only, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3359544.

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Meneksegil, Anouk. „Le dire et l'indicible“. Paris 4, 1992. http://www.theses.fr/1991PA040185.

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Comment saisir l'indicible, s'il est fondamentalement indéfinissable, sans céder à la tentation de l'entourer de l'aura obscure et inaccessible des mystères ? Si l'on se réfère à la simple morphologie, le préfixe latin qui indique la privation, le manque, l'absence de quelque chose, bouleverse le domaine auquel il s'applique, en le bloquant et contraignant à l'intérieur de sa limite. La construction apparente de l'indicible à partir du dicible peut tromper entièrement sur son sens ou même sa tonalité; on peut croire à une extrapolation de l'indicible à partir d'un dicible qui serait déjà là; la réflexion montre aussitôt que la présence secrète et préalable d'un indicible fait comme surgir la dicible auquel nous aboutissons
Assuming that the inexpressible is fundamentally undisable, how can one grasp it without being tempted to shroud it in the obscure and untouchable aura of mysteries? From morphological point of view, the Latin privative prefix which expressive the lack or the absence of something disrupts the field it applies to, tightening and restraining it into its limits. One can be mistaken about the meaning and tonality of an apparent pattern of the inexpressible on the expressible thus extrapolating the inexpressible from the expressible which already exist. When one thinks about it, one becomes aware that the secret and prior presence of the inexpressible seems to make the expressible we end up in turn up again

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Klaue, Yvonne. „Analysis of Dicer homologues in Arabidopsis“. Thesis, University of East Anglia, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.423797.

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Leclerc-Olive, Michèle. „Le dire de l'évènement (biographique)“. Lille 1, 1993. http://www.theses.fr/1993LIL12003.

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Panassiti, Antonio. „General relativity limit of Brans-Dicke gravity“. Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23344/.

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In Brans-Dicke gravity a scalar field non-minimally coupled with the curvature acts as a new gravitational degree of freedom in addition to the usual metric field of General Relativity. Usually, when the coupling ω of the scalar field diverges, the latter approaches a constant and the solutions of the theory reduce to those generated by the Einstein equations with the same energy-momentum tensor as source. However, in the limit ω → ∞, the static and spherically symmetric vacuum solutions, called Brans solutions, do not reduce to the Schwarzschild metric, the only solution of General Relativity with the same type of symmetry. In this work we test their limit with a new method. Unlike the usual way, we use the Brans solutions to take the limit at the level of the equations. Since these are non-linear field equations depending on ω, in principle our procedure could lead to a different outcome. In particular, we take advantage of the Einstein frame formulation of the Brans-Dicke theory and we check if the solutions are able to satisfy the equations of the so called Minimal Geometric Deformation approach. Namely, we study if they can be seen as a geometric deformation - due to the Brans-Dicke scalar - of the Schwarzschild solution. Indeed, the peculiar feature of the geometric deformation is that it is built in such a way to guarantee a clear limit to the vacuum equations of General Relativity. However, we find that the Brans solutions do not meet all the requirements imposed by the structure of the Minimal Geometric Deformation approach. This result supports the conclusion that there is no simple limiting procedure in which the complete Brans-Dicke theory just reduces to General Relativity.

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Körner, Swen. „Dicke Kinder - revisited zur Kommunikation juveniler Körperkrisen“. Bielefeld Transcript, 2007. http://d-nb.info/988749025/04.

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Tong, Xiaohui. „Rôle de la synthèse des miARN par le tissu adipeux dans les pathologies de vieillissement“. Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30332.

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Au cours du vieillissement, le tissu adipeux devient sénescent ce qui conduit à une altération des capacités fonctionnelles de l'adipocyte. En effet, la senescence est un arrêt du cycle cellulaire qui entraîne la perte de fonction et entretient un profil inflammatoire. Ces changements participent à l'installation progressive de pathologies associées au vieillissement comme le diabète, l'athérosclérose ou les maladies neurodégénératives. Afin de mieux comprendre le rôle des sécrétions de l'adipocyte dans la perte de fonction de cette cellule, nous avons analysé la production de micro ARNs de l'adipocyte âgé chez la souris. Depuis plusieurs années, l'étude des micros ARNs montre que ces molécules pourraient devenir des cibles thérapeutiques de premier plan ou des biomarqueurs spécifiques. Dans ce contexte, nous avons analysé et caractérisé le MiRnome de l'adipocyte chez la souris âgée et nous avons pu démontrer que le Mir-1949 pouvait jouer un rôle important dans la perte de fonction de l'adipocyte au cours du vieillissement. En effet, l'expression et la sécrétion adipocytaire de mir- 1949 sont augmentées avec l'âge et semblent être associées à l'état de senescence de la cellule adipeuse. De plus, l'augmentation de mir-1949 provoque une altération des fonctions de l'adipocyte in vitro. L'ensemble de ces résultats préliminaires montre que mir-1949 pourrait devenir une adipokine d'intérêt à cibler au cours du vieillissement
On the one part, dicer, the RNase III endoribonuclease responsible for microRNAs maturation, has been reported to be decreased in adipocytes during ageing. With the use of tamoxifen inducible dicerlox/lox/ adiponectin-CreERT2 mice, we found that adipocyte dicer deficiency promoted the onset of some of the age-related complications such as reduced adipocyte sizes and dysfunctions in systemic metabolism. The abrogation of white adipocyte markers such as Pparγ, Glut4 or Hsl, indicated that dicer is indispensible for the maintainance of white adipocyte identity. In addition, the results that there were lipid accumulation and fibrosis in liver in tamoxifen treated dicerlox/lox/ adiponectin-CreERT2+ mice, indicated that adipocyte dicer deficiency might contribute to liver aging. Mechanistically, mitochondrial function seemed to be upregulated due to adipocyte dicer deficiency, indicated by increased protein levels of OXPHOS components and PGC1α. In line, mitochondria repressors FOXO1 and FOXO3 were phosphorylated and inactivated, whose downstream antioxidant targets Catalase and Sod were also decreased. Moreover, P16, a marker of senescence, exhibited a trend to be increased due to adipocyte dicer deficiency. Since mitochondrial ROS surplus can lead to DNA damage and senescence, we assured that adipocyte dicer deficiency might induce a combination of mitochondrial activation and reduction in detoxification reduction possibly mediated by the inactivation of FOXO1 and FOXO3a. Finally, the result that nutrient restriction positively regulated dicer level in adipocytes further supported that there is a conserved aging pathway in adipocytes involving dicer. On the other part, through microarray screen and RT-qPCR validation, we reported that aging increased mir-1949 in adipocytes in wild type mice and possibly promoted its secretion from perigonadal adipose tissue in vitro. Correspondingly, in vitro results also suggested that senescence increased mir-1949 production and secretion from adipocytes. Functionally, upregulation of mir-1949 in 3T3-F442A adipocytes negatively regulated mitochondrial complex II protein level and oxygen consumption capability, associated with lipid accumulation. Interestingly, sustained upregulation of mir-1949 during adipogenesis of 3T3-F442A preadipocytes, tended to increase white adipocyte markers, such as Leptin, Glut4 or Hsl. Finally, combined with the results that 24h fasting significantly increased mir-1949 in perigonadal adipose tissue as well as that upregulation of mir-1949 exhibited a trend to increase lipid accumulation in senescent 3T3-F442A adipocytes, we assured that aging increases mir-1949 expression in adipocytes which might try to rescue age-related dysfunctions in adipocytes, such as impaired lipid storage. Nevertheless, the precise actions of mir-1949 need to be validated in vivo by injection of AAV-aP2-mir-1949 mimic into aged mice

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Tamas, Jennifer. „Dire de ne pas dire : du silence éloquent à l'énonciation tragique des déclarations d'amour chez Racine“. Thesis, Paris 4, 2012. http://www.theses.fr/2012PA040268.

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Nous formons l’hypothèse que Racine met en scène une lutte contre l’indicible. Dans chaque pièce, il s’agit de révéler quelque chose d’inacceptable et d’impossible à dire. Comment dire ce qu’on ne peut pas dire ? Et surtout, comment ne pas provoquer l’effroi de celui qui écoute ? Le silence, qu’il représente une pure absence de mots ou un bruissement de voix permettant de ne pas répondre, se trouve ainsi au coeur de l’échange dialogique. La déclaration d’amour relève de cet indicible et suscite une tension permanente entre « dire » et « taire ». Cette étude s’articule donc autour du paradoxe suivant : parler est impossible, mais la réticence à dire, une fois surmontée, produit l’irrémédiable. La déclaration d’amour est l’emblème de ce procédé. Elle représente l’énoncé tragique par excellence, puisqu’elle engendre la fatalité. Révéler l’amour, c’est condamner l’autre. L’oracle fatal s’exprime par la bouche des personnages amoureux. Racine donne ainsi naissance à un nouveau théâtre de l’amour dans lequel la déclaration correspond à une crise existentielle. Le personnage racinien affirme son être-au-monde par l’expression de son amour qui fait violence à l’autre
I argue that Racine represents the fight against the unspoken. Each play reveals something that is unacceptable and impossible to articulate. How does one state all that cannot be stated? Above all, how to avoid stirring the terror of the listener? Silence, whether it represents a pure absence of words or a murmuring of voices that inhibit an answer, finds itself at the core of the discursive exchange. The declaration of love emerges from the unsaid and brings about a permanent tension between « the spoken word » and « silence. » This study is based on the following paradox: speech is impossible, but the reticence to speak, once overcome, induces an irreversible process. The declaration of love is the symbol of this process. Its utterance represents the ultimate tragic enunciation as it engenders Fate. To show one’s love is to condemn the other.The fatal oracle expresses itself through the words of characters in love.Racine inaugurates a new theater of love in which the declaration corresponds to a deep existential crisis. The Racinian character asserts his subjectivity by expressing his love, though it violates the other

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Lane, Tasha Ann. „Gender and the Voir Dire Process“. PDXScholar, 2019. https://pdxscholar.library.pdx.edu/open_access_etds/5068.

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The jury selection process (also known as voir dire) has been examined previously in many ways, including racial impacts. Previous research suggests the need for more examination of how and if gender impacts the voir dire process. The lack of knowledge about how gender impacts voir dire might also have implications for public respect and trust in the court system. For example, theories of procedural justice suggest that individual experiences with the legal system affect whether they view the entire legal system as being legitimate. This is important because this perception then impacts how the public interact with the system. This research examines one main research question, how is gender salient in the voir dire process? To understand how gender impacts voir dire, including how attorneys and potential jurors communicate with each other, courtroom observations of the voir dire process were conducted. During these observations coding sheets were used focusing on types of questions asked by attorneys and reactions of the potential jurors and how gender affected this process. Over 150 interactions with potential jurors were examined. The results of these interactions focus on the use and misuse of gendered titles, gendered expectations, and repetition. It was found that gender is salient throughout the process and may impact how attorneys present the questions they ask and the information they give. The results of this research are applicable to jury selection/voir dire research and are important to better understanding how gender is seen and acted out in the courtroom.

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Bonnet, Agathe. „Dire et faire dire l'indicible : Entre secret et stigmate, l'analyse d'un processus d'enquête sociologique sur le ballonnement“. Phd thesis, Université René Descartes - Paris V, 2012. http://tel.archives-ouvertes.fr/tel-00689002.

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La thèse s'intéresse aux enjeux méthodologiques présents en situation d'enquête de terrain. Les enquêtes qualitatives réalisées dans le cadre de cette recherche visaient à explorer un trouble de santé. L'enquête portant sur le trouble du ballonnement met notamment en avant le jeu interactionnel entre enquêtée et enquêtrice, et fait apparaître les concepts de stigmate et de secret. L'analyse des interactions sociales entre ces deux acteurs invite à percevoir l'enquête comme un processus au sein duquel différentes phases se déclinent et interagissent ensemble. A partir du recrutement jusqu'à la clôture du terrain, les effets de l'enquête sont observés et analysés à travers le double regard de l'enquêtrice et de l'enquêtée. Nous qualifions cette démarche méthodologique d' " observation interactive ", puisant ses fondements au sein de la méthode d'observation participante et de la tradition de l'interactionnisme symbolique. Une réflexion est également menée sur les effets de réciprocité entre l'élaboration de stratégies d'enquête et le déroulement de l'enquête soumise à l'imprévisibilité du terrain.

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Bonnet, Agathe. „Dire et faire dire l'indicible : Entre secret et stigmate, l’analyse d’un processus d’enquête sociologique sur le ballonnement“. Thesis, Paris 5, 2012. http://www.theses.fr/2012PA05H003/document.

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La thèse s’intéresse aux enjeux méthodologiques présents en situation d’enquête de terrain. Les enquêtes qualitatives réalisées dans le cadre de cette recherche visaient à explorer un trouble de santé. L’enquête portant sur le trouble du ballonnement met notamment en avant le jeu interactionnel entre enquêtée et enquêtrice, et fait apparaître les concepts de stigmate et de secret. L’analyse des interactions sociales entre ces deux acteurs invite à percevoir l’enquête comme un processus au sein duquel différentes phases se déclinent et interagissent ensemble. A partir du recrutement jusqu’à la clôture du terrain, les effets de l’enquête sont observés et analysés à travers le double regard de l’enquêtrice et de l’enquêtée. Nous qualifions cette démarche méthodologique d’ « observation interactive », puisant ses fondements au sein de la méthode d’observation participante et de la tradition de l’interactionnisme symbolique. Une réflexion est également menée sur les effets de réciprocité entre l’élaboration de stratégies d’enquête et le déroulement de l’enquête soumise à l’imprévisibilité du terrain
This thesis concerns methodological matters existing in the situation of fieldwork. Here the qualitative survey realized in the frame of this research was to explore minor health issues. The survey conducted on bloating issue does notably shed light on the ‘interactional game’ between a female interviewee and a female interviewer revealing the key concepts of stigma and secrecy. Indeed, the analysis of social interactions between both actors incites to perceive the notion of fieldwork as a process where different phases decline and interact altogether. From the recruitment procedure to the closure of the survey, the effects of the investigation are observed and analyzed through a dual “eye”, the interviewee and interviewer. We qualify this methodological approach as “interactive observation”. This “interactive observation” feeds its very principle within the methodology relative to the ideas of participative-observation and the tradition of symbolic interactionism. A reflection is lead on the effects of reciprocity between the elaboration of the fieldwork’s strategies and the unfolding of the study submitted to the unpredictability of the fieldwork

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Lai, Yiu-yan, und 黎耀恩. „Charged generalised Brans-Dicke theory in quantum cosmology“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31221087.

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Santos, Sérgio Mittmann dos. „Cordas cósmicas girantes na gravitação de Brans-Dicke“. Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/153631.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A partir da teoria da gravitação de Brans-Dicke, são obtidas soluções exatas para as cordas cósmicas girantes. As soluções são para cordas retas, que preservam a simetria de Lorentz ao longo do eixo longitudinal de simetria, e para as não retas, com simetria aproximadamente cilíndrica e que violam a simetria de Lorentz. Essas soluções permitem verificar se os espaços-tempos das cordas são regulares ou apresentam singularidades. Além disso, a possibilidade de que as cordas sejam fontes de curvas tipo-tempo fechadas também é analisada. Exclusivamente para as cordas retas, é verificado se essas se mantiveram estáveis após as suas eventuais formações, e se uma escolha adequada para as constantes de integração das soluções impede a existência das curvas tipo-tempo fechadas. Desde a década de 1930, as observações mostram que as velocidades tangenciais das estrelas das galáxias têm um comportamento que contraria o que é previsto quando se considera somente a presença de matéria visível: à medida que as distâncias até os centros das galáxias aumentam, as velocidades também aumentam, até que começam a tender para valores aproximadamente constantes. A razão para esse fenômeno ainda está sob debate. Por enquanto, é justificado pela presença de matéria escura nos halos das galáxias, mas a própria matéria escura ainda não é bem entendida. Em 1980, para 21 galáxias do tipo Sc, as observações mostraram que esse crescimento das velocidades até atingirem os valores constantes ocorre quando as distâncias crescem por 2 a 3 ordens de grandeza. Com as soluções da teoria de Brans-Dicke para as cordas não retas, é proposto um espaço-tempo com a mesma simetria aproximadamente cilíndrica, que descreve adequadamente esse comportamento nas velocidades das estrelas daquelas 21 galáxias
From the Brans-Dicke theory of gravitation, exact solutions are obtained for the spinning cosmic strings. The solutions are for straight strings, which preserve the Lorentz symmetry along the longitudinal axis of symmetry, and for the non-straight strings, with nearly cylindrical symmetry and which violate the Lorentz symmetry. These solutions allow us to verify if the spacetimes of the strings are regular or have singularities. In addition, the possibility that the strings are sources of closed timelike curves is also analyzed. Only for the straight strings, it is verified if these have remained stable after their eventual formations, and if a suitable choice for the integration constants of the solutions prevents the existence of the closed timelike curves. Since the 1930s, observations have shown that the tangential velocities of galaxies’ stars have a behavior that goes against what is predicted when considering only the presence of visible matter: as distances to the centers of galaxies increase, velocities also increase until they begin to tend to approximately constant values. The reason for this phenomenon is still under discussion. For now, it is justified by the presence of dark matter in the halos of galaxies, but the dark matter itself is still not well understood. In 1980, for 21 Sc-type galaxies, observations showed that such velocities growth until reaching constant values occurs when distances grow by 2 to 3 orders of magnitude. With the solutions of the Brans-Dicke theory for the non-straight strings, a spacetime with the same nearly cylindrical symmetry is proposed, which adequately describes this behavior in the velocities of the stars of those 21 galaxies

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Taylor, David W. Jr. „Structural Basis for RNA Processing by Human Dicer“. Thesis, Yale University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3578460.

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Dicer plays a central role in RNA interference pathways by cleaving double-stranded RNAs (dsRNAs) to produce small regulatory RNAs. Human Dicer can process long double-stranded and hairpin precursor RNAs to yield short interfering RNAs (siRNAs) or microRNAs (miRNAs), respectively. In humans, Argonaute2 (AGO2) assembles with the guide RNA-generating enzyme Dicer and either the RNA-binding protein TRBP or PACT to form a RISC-loading complex (RLC), which is necessary for efficient transfer of nascent siRNAs from Dicer to AGO2. Here, I have used electron microscopy and single particle analysis of human Dicer-RNA complexes and the RLC to gain insight into the structural basis for human Dicer's substrate preference and RISC-loading. My studies show that Dicer traps pre-siRNAs in a non-productive conformation, while interactions of Dicer with pre-miRNAs and dsRNA binding proteins induce structural changes in the enzyme that enable productive substrate recognition in the central catalytic channel. The RLC Dicer's N-terminal DExH/D domain, located in a short base branch, interacts with TRBP, whereas its C-terminal catalytic domains in the main body are proximal to AGO2. A model generated by docking the available atomic structures of Dicer and Argonaute homologs into the RLC reconstruction suggests a mechanism for siRNA transfer from Dicer to AGO2.

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Lima, Sarah Azoubel 1987. „Estudo do metabolismo de microRNAs na resistência de células leucêmicas“. [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314036.

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Orientador: Carmen Veríssima Ferreira
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A resistência à quimioterápicos é um dos principais obstáculos para a terapia do câncer. Na leucemia mielóide crônica (CML) o tratamento é frequentemente ineficiente devido à aquisição de resistência aos quimioterápicos utilizados. Dessa forma, o estudo comparativo de linhagens celulares de CML resistentes e susceptíveis a drogas é de extrema importância para o entendimento dos mecanismos moleculares da resistência e para a evolução de novos protocolos terapêuticos. Um número cada vez maior de evidências indica que os microRNAs apresentam importante papel no processo de carcinogênese e na agressividade tumoral. Nesse trabalho o principal objetivo é melhor esclarecer o papel da maquinaria de processamento de microRNAs no fénotipo MDR (multi-drug resistance), utilizando principalmente as linhagens de CML K562 (susceptível) e Lucena (fenótipo MDR). Nossos resultados revelaram que as células Lucena apresentam altos níveis da endonuclease Dicer e que os microRNAs let-7a e miR-145 são intensamente regulados em relação à K562. Além disso, a linhagem Lucena se tornou mais sensível ao quimioterápico vincristina após o silenciamento de Dicer. Experimentos com outras linhagens celulares mostraram que a resistência frente à cisplatina e doxorrubicina possui correlação significativa com os níveis de Dicer. A identificação de ligantes dessa endonuclease nas linhagens de CML ressalta a possibilidade desta enzima estar cumprindo novos papéis no fenótipo MDR. Entre os ligantes exclusivos da linhagem resistente, estão proteínas envolvidas na promoção de defesa anti-oxidante, proliferação celular e metabolismo de lipídios e hormônios esteróides. De acordo, dados de proteoma das duas linhagens enfatizam a importância do metabolismo lipídico para aquisição da resistência, bem como de um intenso remodelamento do citoesqueleto. Nossos dados reforçam o caráter complexo e multifatorial da resistência à múltiplas drogas, contribuindo para o entendimento do ação de miRNAs e de Dicer nesse processo
Abstract: Drug resistance is one of the main obstacles in cancer therapy. Frequently, the treatment of chronic myelogenous leukemia (CML) becomes inefficient due to the emergence of a resistant population of cancer cells. Therefore, comparative studies of resistant and non-resistant CML cell lines is extremely important to the understanding of molecular mechanisms involved in the acquisition of resistance and also to the evolution of new therapeutic protocols. A growing number of evidence supports an important role for microRNAs in carcinogenesis and tumoral aggressiveness. This study aims to better understand the role of microRNAs and their biosynthetic pathway in the phenotype of multi-drug resistance (MDR) of CML cells. To this purpose we worked with the leukemic cell lines K562 (non-resistant) and Lucena (MDR phenotype). The results obtained revealed that Lucena expresses high levels of Dicer endonuclease and intensely regulates microRNAs let-7a and miR-145 when compared to K562. Also, Dicer silencing in MDR cells enhanced sensitivity to the chemotherapic drug vincristine. Experiments with different cells lines showed that resistance to cisplatin and doxorubicin are correlated to Dicer expression levels. In CML cell lines, the identification of Dicer ligands points to the possibility of alternative roles for this endonuclease in the MDR phenotype. Among the newly found interactors in the resistant cell line are proteins involved in antioxidant defense, proliferation and metabolism of fatty acids and steroids. Accordingly, proteome data from K562 and Lucena cells emphasizes the importance of lipid metabolism and structural remodeling to the resistant phenotype. Overall, our data contributes to the understanding of the role played by microRNAs and Dicer in the complex and multifactorial MDR phenotype
Mestrado
Bioquimica
Mestre em Biologia Funcional e Molecular

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Paulo, Walter de Oliveira. „Gravitação newtoniana modificada a partir da teoria gravitacional de Brans-Dicke“. Universidade Federal de Roraima, 2011. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=52.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Investigamos inicialmente o problema da obtenção de uma gravitação newtoniana modificada no caso da teoria da Relatividade Geral. Na sequência, encontramos uma solução geral com simetria esférica para um campo gravitacional fraco no contexto da Teoria de Brans-Dicke. Esta solução é independente de qualquer condição de coordenada. Então, para uma escolha conveniente da função f(r) na métrica de Brans-Dicke, exibimos uma fórmula modificada para a gravitação newtoniana, a qual pode descrever a gravidade em uma escala de comprimento pequena. Discutimos os resultados em comparação com o caso da Relatividade Geral
We investigate initially the problem of obtaining a modified newtonian gravitation in the case of General Relativity theory. Following, we find a general solution with spherical symmetry for a weak gravitational field in the context of Brans-Dicke theory. This solution is independent of any coordinate condition. Then, for a convenient choice of the function f(r) in Brans-Dicke metric, we exhibit a modified formula to newtonian gravity, which can describe gravity in a small length scale. We discuss the results in comparison with the case of General Relativity

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Tran, Thi Phuong Anh. „Conception, synthèse et évaluation biologique de nouveaux ligands d'ARN en tant qu'inhibiteurs de la production de microARN oncogènes“. Thesis, Université Côte d'Azur (ComUE), 2016. http://www.theses.fr/2016AZUR4076/document.

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Les microARN (miARN) constituent une classe de petits ARN non-codants qui jouent un rôle clé dans la régulation de l’expression des gènes au niveau post-transcriptionnel. De nombreuses études ont démontré que la surexpression de certains miARN est liée au développement de plusieurs types de cancer. C’est pour cette raison les miARN représentent une nouvelle classe de cibles thérapeutiques à haute potentielle. Dans ce contexte, l’objectif de mon travail de thèse était la découverte de nouveaux inhibiteurs de la production de miARN oncogène. Dans ce but, j’ai suivi deux approches, différentes mais complémentaires : (i) le criblage d’une petite librairie de composés et (ii) la conception et la synthèse de nouveaux conjugués en tant que ligands de précurseurs de miARN (pré-miARN). En particulier, nous avons ciblé les miARN-372 et -373 qui sont oncogènes dans plusieurs cancers, tels que le cancer gastrique. Nous avons ainsi démontré que certains des composés criblés ou synthétisés sont capables de se lier efficacement à la structure secondaire en tige-boucle de pré-miARN avec une haute affinité, conduisant à l’inhibition de la production des miARNs correspondants. Par ailleurs, nous avons montré que certains composés possèdent une activité anti-proliférative spécifique pour les cellules de cancer gastrique et que cette activité est directement liée à une diminution de la production de miARN ciblés et au rétablissement de la traduction de ARN messenger
MicroRNAs (miRs) are a class of small non-coding RNAs that act as regulators of gene expression at the post-transcriptional level. Increasing evidence has indicated that the deregulation of miR expression is linked to various human cancers and therefore, miRs represent a new class of potential drug targets. In this context, my PhD project focused on the discovery of new inhibitors of oncogenic miRs production. Toward this aim, two different but complementary approaches were followed: (i) the screening of small libraries of compounds and (ii) the design and synthesis of new classes of conjugates as binders of miRNA precursors (pre-miRs). In particular, we focused our attention on miR-372 and miR-373, two oncogenic miRs overexpressed in various cancers, such as gastric cancer. We showed that some of the screened or of the newly synthesized compounds are able to efficiently bind to stem-loop structured precursors of the targeted miRs with high affinity, thus inhibiting the production of their corresponding mature miRs at the level of Dicer cleavage. Moreover, we found compounds bearing a specific anti-proliferative activity in gastric cancer cells overexpressing targeted miRs and this activity is directly linked to a decrease in the production of oncogenic miR-372 and -373 and to the restoration of normal mRNA translation

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Montiglio, Silvia. „Dire le silence au pays du logos“. Paris, EHESS, 1995. http://www.theses.fr/1995EHES0014.

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S'agissant d'une culture, celle de la grece antique, qui a mis le dire au coeur de sa definition de l'homme et de ses activites, le silence est percu comme un comportement jamais neutre : a la fois marque d'exclusion et arme d'agression, il est egalement l'annonciateur invisible de malheurs. Instrument essentiel de la ruse, le silence peut decider du succes s'il est savamment articule, selon l'imperatif du kairos, avec la parole et l'action
In the civilisation of ancient greece, where speaking occupied a central place in the very definition of human identity and action, silence is imbued with deep and consequential meaning : as a mark of exclusion, as an arm of agression, as the invisible messenger of ill events. Since silence is also a major instrument of cunning intelligence, it can grant succes to those who know how to articulate, according to the impelling kairos, silence, words and action

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Jalenques-Vigouroux, Béatrice. „Dire l'environnement : le métarécit environnemental en question“. Paris 4, 2006. http://www.theses.fr/2006PA040124.

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La thèse interroge la façon dont des organisations construisent l’environnement au sein de leurs discours et comment le narratif intervient dans cette construction. Notre point de vue repose sur le fait que la pensée environnementale participe à la crise de l’« idéologie économique ». Nous avons étudié trois types d’organisation : une entreprise, SITA France (SUEZ), une institution, l’Agence de l’environnement et de la Maîtrise de l’Energie (ADEME), une association, France Nature Environnement (FNE). En outre, nous avons examiné un dispositif de concertation rassemblant ces trois catégories d’organisation. Le critère de sélection de ces entités est qu’elles revendiquent elles-mêmes l’identité d’acteur de l’environnement. Plutôt que l’exhaustivité, notre objet nous permet d’approcher l’amplitude de diversité des discours construisant l’environnement. L’étude des ces organisations en France permet de comprendre que l’environnement est construit sous au moins deux types de discours, le type de discours économique et le type de discours environnementaliste. L’étude des représentations sociales associées à des termes récurrents au sein du type de discours environnementaliste permet l’observation de ferments de narrativité. Ces ferments de narrativité permettent de reconstruire les différentes composantes d’un récit potentiel particulier, le métarécit, en en modifiant certaines : « incitation à l’action », « héros anonymes », « grand but », « grand péril », et « valeur suprême » composent ainsi le « métarécit » environnemental
This thesis analyses how organisations build the environment into their discourses and how the narrative participates in this construction. Our position is that environment thinking is understood as a part of the crisis in “economic ideology”. It studies three kinds of organisations : a firm, SITA France (SUEZ); a public institution, Agence de l’Environnement et de la Maîtrise de l’Energie (ADEME); and a non-profit organisation, France Nature Environnement (FNE). In addition, it examines a communication organ constituted by these three types of organisations. The criteria used to select these organisations were that they identified themselves as environmental players. More than exhaustivity, our object permits us to measure the amplitude of the discourse used to construct the environment. The study of these French organisations uncovers the fact that the environment is constructed via two distinct types of discourse, the economic type and the environmental type. The study of the social representations associated with frequently-used words within the environmental type of discourse brings to light certain “fermenting agents in a developing narrative”. These “fermenting agents in a developing narrative” allow us to reconstitute the components of a particular potential story, the “meta narrative”: “action”, “anonymous heroes”, “a great peril”, “a lofty ideal”, and “supreme value”, all of which constitute the environmental “metanarrative”

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Noonan, Eric S. „Slice—n—Dice Algorithm Implementation in JPF“. BYU ScholarsArchive, 2014. https://scholarsarchive.byu.edu/etd/4147.

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This work deals with evaluating the effectiveness of a new verification algorithm called slice--n--dice. In order to evaluate the effectiveness of slice--n--dice, a vector clock POR was implemented to compare it against. The first paper contained in this work was published in ACM SIGSOFT Software Engineering Notes and discusses the implementation of the vector clock POR. The results of this paper show the vector clock POR performing better than the POR in Java Pathfinder by at least a factor of two. The second paper discusses the implementation of slice--n--dice and compares it against other verification techniques. The results show that slice--n--dice performs better than the other verification methods in terms of states explored and runtime when there is no error in the program or little thread interaction is needed in order for the error to manifest.

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Fellman, Laura Suzanne. „The Genetic Algorithm and Maximum Entropy Dice“. PDXScholar, 1996. https://pdxscholar.library.pdx.edu/open_access_etds/5247.

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The Brandeis dice problem, originally introduced in 1962 by Jaynes as an illustration of the principle of maximum entropy, was solved using the genetic algorithm, and the resulting solution was compared with that obtained analytically. The effect of varying the genetic algorithm parameters was observed, and the optimum values for population size, mutation rate, and mutation interval were determined for this problem. The optimum genetic algorithm program was then compared to a completely random method of search and optimization. Finally, the genetic algorithm approach was extended to several variations of the original problem for which an analytical approach would be impractical.

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He, Qiwei. „Le dire-vrai chrétien selon Michel Foucault“. Thesis, Lyon, 2019. http://www.theses.fr/2019LYSEN075/document.

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La lecture foucaldienne des Pères de l'Église dans les années 1980 occupe une place centrale dans son projet de généalogie du sujet moderne. L'un de ses axes le plus important est l'analyse du dire-vrai chrétien. La formation d’un discours analytique de soi, conjuguée avec l'obligation d'obéissance totale à l'autre constitue une partie essentielle de la subjectivation chrétienne. Notre analyse porte sur les diverses formes que prend l'obligation fondamentale de manifester sa vérité, dans les trois pratiques chrétiennes du baptême, de la pénitence et de la direction de conscience. Nous proposons une lecture critique de l'analyse foucaldienne du dire-vrai chrétien dans le cours de 1980 Du gouvernement des vivants, Mal faire dire vrai et Les aveux de la chair, en examinant la singularité de sa méthode par rapport aux historiens. Nous retraçons également l'évolution de la manière dont Foucault problématise son analyse du christianisme et en élargit le cadre historique. Nous proposons enfin une approche comparative du dire-vrai dans la philosophie confucéenne et le christianisme primitif
The Foucaldian reading of the Church Fathers in the 1980s occupies a central place in his project of genealogy of the modern subject. One of its most important axes is the analysis of the Christian notion of truth-telling. The formation of an analytic discourse of self, combined with the obligation of total obedience to the other, is an essential part of Christian subjectivity. Our analysis focuses on the various forms of the basic obligation to manifest one's truth in the three Christian practices of baptism, penance, and the direction of consciousness. We propose a critical reading of the Foucauldian analysis of the Christian truth-telling in the course of 1980, On the Government of the living, Wrong-doing, Truth-telling and Confessions of the Flesh, by examining the singularity of its method compared to historians. We also retrace the evolution of the way Foucault problematizes his analysis of Christianity and broadens the historical context. Finally, we propose a comparative reading of the notion of truth-telling both in Confucian philosophy and early Christianity

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MUSI, ELISABETTA. „Dire il mondo Abitare pedagogicamente le parole“. Doctoral thesis, Università degli Studi di Milano-Bicocca, 2021. http://hdl.handle.net/10281/315632.

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La parola rivela il nostro rapporto con l’esistenza, dice di derive e smarrimenti o al contrario di posture esistenziali salde e consapevoli. Mancare di parole con cui dire di sé, della propria relazione col mondo, è mancare di presa sul reale. Chi si dedica ai compiti educativi e di cura dovrebbe farlo ponendo anzitutto attenzione alle parole con cui il soggetto rappresenta se stesso e il rapporto con la realtà che lo circonda. Ma cosa fa sì che una parola possa dirsi educativa? La pedagogia di orientamento fenomenologico-esistenziale costituisce l’orizzonte ermeneutico di riferimento da cui ha preso le mosse la ricerca, che ha inteso verificare la fondatezza dei suoi presupposti teorici analizzando l’utilizzo della parola in tre contesti dichiaratamente o implicitamente educativi: i servizi educativi per l’infanzia, il carcere, l’ospedale. La ricerca esplorativa è iniziata con la realizzazione di alcuni focus group che hanno coinvolto: - un gruppo di educatrici di nido e docenti della scuola dell’infanzia, - le conduttrici e i conduttori di laboratori di narrazione e di scrittura autobiografica in carcere, - un gruppo di medici e operatrici sanitarie. Questi confronti hanno fornito indicazioni utili per la costruzione di tre tipologie di questionari che sono stati poi inviati agli stessi operatori e a loro colleghi. Dall’elaborazione delle risposte, sono emersi stimoli di pensiero e indicazioni operative per la costruzione di una teoria critica in grado di definire condizioni e caratteristiche affinché la parola possa dirsi efficacemente educativa.
The word reveals our relationship with existence, it speaks of drifts and bewilderments or, on the contrary, of firm and conscious existential postures. Lacking words with which to talk about oneself, about one's relationship with the world, is to lack a grip on reality. Whoever dedicates himself to the tasks of education and care should do so by first of all paying attention to the words with which the subject represents himself and his relationship with the reality that surrounds him. But what makes a word educational? Phenomenological-existential pedagogy constitutes the hermeneutic horizon of reference from which the research began. It aimed to verify the validity of its theoretical assumptions by analysing the use of words in three declared or implicitly educational contexts: educational services for children, prisons and hospitals. The exploratory research began with the realisation of some focus groups that involved - a group of nursery educators and preschool teachers, - a group of nursery school teachers and nursery school teachers, the leaders of storytelling and autobiographical writing workshops in prison, - a group of doctors and health workers. These comparisons provided useful indications for the construction of three types of questionnaires which were then sent to the same operators and their colleagues. From the elaboration of the answers, thought stimuli and operational indications emerged for the construction of a critical theory capable of defining conditions and characteristics so that the word can be effectively educational.

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Lapointe, Francis. „Analyse sémantique et description lexicographique de marqueurs pragmatiques construits avec VRAI en français québécois vraiment, pas vraiment, pour de vrai, pour dire vrai, à vrai dire et à dire vrai“. Mémoire, Université de Sherbrooke, 2005. http://savoirs.usherbrooke.ca/handle/11143/2455.

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Cette étude porte sur certains marqueurs pragmatiques construits avec le mot vrai d'après l'usage québécois: vraiment, pas vraiment, pour de vrai, pour dire vrai, à vrai dire et à dire vrai. L'analyse et la description linguistique de ces mots suivent les lignes directrices de la méthode lexicographique propre au modèle Sens-Texte. L'étude fait état de la polysémie des marqueurs et de la cohérence du champ lexical qu'ils forment. On y explore le sémantisme du mot vrai, de son sens le plus primitif à son sens métaphorique, en passant par celui faisant appel au concept de caractéristiques prototypiques à la source de certaines lexies"intensificatrices" de vraiment et pour de vrai . On y dévoile aussi, entre autres, le mécanisme d'euphémisation propre à la locution pas vraiment et les fonctions de connecteurs textuels des locutions pour dire vrai, à vrai dire et à dire vrai.

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Lapointe, Francis. „Analyse sémantique et description lexicographique de marqueurs pragmatiques construits avec VRAI en français québécois vraiment, pas vraiment, pour de vrai, pour dire vrai, à vrai dire et à dire vrai /“. [S.l. : s.n.], 2005.

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Benoit, Matthieu. „Etudes biophysiques de l'interaction entre la protéine humaine TRBP et un précurseur de microARN oncogène“. Phd thesis, Université de Grenoble, 2013. http://tel.archives-ouvertes.fr/tel-01038628.

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Les microARNs sont une classe de petits ARNs non codants qui régulent l'expression des gènes via un mecanisme d'interference par ARN. Les microARNs humains sont produits par une série de réactions enzymatiques. En particulier, dans le cytoplasme le precurseur de miRNA (pre-miRNA) est reconnu et clivé par un complexe contenant l'enzyme RNAse III Dicer et plusieurs cofacteurs protéiques. La proteine TRBP (HIV TAR RNA binding protein) est l'un de ces cofacteurs et augmente la stabilité du complexe, influe sur la cinétique, la position du clivage et a role potentiel dans la reconnaissance du substrat et dans le transfet du produit vers le complexe RISC (RNA-induced silencing complex) effecteur de l'interference par ARN. TRBP est composé de 3 domaines de liaison aux ARN doubles brin (dsRBDs). La région d'interaction de TRBP avec les ARNs est composé des deux premiers dsRBDs liés par une région interdomaine non charactérizée. La présente étude rapporte la caractérisation biophysique in vitro de la région d'interaction avec les ARNs de TRBP dans l'état apo de TRBP ou dans l'état lié avec les deux precurseurs cytoplasmique successifs du microARN oncogène miR-155 comprenant la tige boucle pre-miR-155 et le duplex miR-155/miR-155* résultat du clivage de pre-miR-155 par Dicer. L'étude montre que la région d'intéraction de TRBP avec les ARNs est monomerique, est composée de deux dsRBDs independants en solution et que la région interdomaine de 60 résidus est flexible. Le premier dsRBD, non caractérisé précédement en solution est le siège d'un equilibre plié/déplié integral dans une grande gamme de conditions physico-chimiques. Les deux premiers dsRBDs de TRBP peuvent interagir avec un même precurseur de microARN et deux régions d'interaction de TRBP avec les ARNs peuvent interagir avec un même precuseur. La région d'interaction de TRBP avec les ARNs interagit avec pre-miR-155 et le duplex miR-155/miR-155* avec des affinités très similaires. Dans le complexe avec une région d'interaction de TRBP avec les ARN liée à pre-miR-155 ou au duplexe miR-155/miR-155*, aucune indice de contact entre les deux dsRBDs n'a été detecté et la protéine interagit avec les deux precurseurs par la même surface d'interaction. Les informations récoltées suggèrent que TRBP peut jouer un rôle avant et après le clivage des pre-miARN par Dicer, notamment dans le complexe de chargement de RISC.

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Abel, Yoann. „Caractérisation structurale et fonctionnelle d’une nouvelle interaction entre les protéines RPAP3 et TRBP“. Thesis, Université de Lorraine, 2016. http://www.theses.fr/2016LORR0285/document.

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Récemment, plusieurs études ont permis de mettre en évidence un lien possible entre la maturation des snoARN et celle des microARN, deux familles d’ARNnc impliquées respectivement dans la maturation d’autres ARN, tels les ARNr, et dans la régulation de l’expression des gènes. En effet, ces études ont montré que certains microARN pouvaient être issus de la maturation d’un snoARN précurseur, formant alors une nouvelle classe d’ARNnc, les sdARN (ARN dérivés de snoARN). Le manque d’informations disponibles sur les mécanismes de maturation possibles des sdARN nous a conduit à réaliser un crible double-hybride chez la levure S. cerevisiae entre différentes protéines impliquées dans la biogenèse des snoARN et des microARN. Ce crible a permis d’identifier une nouvelle interaction entre les protéines TRBP, impliquée dans la maturation du pré-microARN en microARN, et RPAP3, un protéine du complexe d’assemblage hR2TP. L’observation de cette interaction soulève plusieurs questions, telles que son implication possible dans la maturation de microARN à partir de snoARN précurseurs, ou encore sur l’implication possible de TRBP et RPAP3 dans la biogenèse des snoRNP ou des microARN, respectivement. Nous avons alors entrepris de caractériser l’interaction entre TRBP et RPAP3. Par des approches de biologie moléculaire, de biochimie et de biologie structurale, nous avons d’une part confirmé l’existence du complexe in vitro et in vivo et identifié les domaines respectifs de TRBP et de RPAP3 impliqués dans l’interaction, ainsi qu’identifié plusieurs mutations intéressantes au niveau de l’interface d’interaction. L’utilisation de ces mutants devrait nous permettre d’étudier l’effet de la perte d’interaction entre TRBP et RPAP3 sur la maturation de différents ARNnc. Enfin, nos travaux ont également permis d’observer que l’interaction entre TRBP et RPAP3 n’était pas compatible avec la formation du complexe entre TRBP et la RNase Dicer. Or, il avait été montré que l’absence de TRBP au niveau de Dicer entraînait dans certains cas la génération de microARN avec des extrémités, et donc des spécificités, altérées (iso-miRs). La formation d’un complexe entre les protéines TRBP et RPAP3 pourrait donc constituer un moyen possible de réguler la disponibilité de TRBP et, indirectement, l’activité de Dicer
Recently, several studies have described a possible link between snoRNA and microRNA maturation, two ncRNA families involved in the maturation of other RNAs, such as rRNA, and in the regulation of gene expression, respectively. Indeed, these studies have shown that some microRNAs could be maturated from a snoRNA precursor, forming a new class of ncRNAs, the sdRNAs (snoRNA-derived RNAs). The mechanism of sdRNA maturation are still poorly understood. Therefore, we have performed a two-hybrid screen in the yeast S. cerevisiae between different proteins involved in microRNAs and snoRNAs biogenesis. Interestingly, we observed a novel interaction between TRBP, involved in the maturation of microRNAs, and RPAP3, a member of the hR2TP complex. The observation of this interaction raises several questions, such as its possible involvement in the maturation of microRNAs from snoARN precursors, or on the possible involvement of TRBP or RPAP3 in snoRNP or microRNA biogenesis, respectively. Using various molecular biology and biochemical approaches, we undertook the functional and structural characterization of the TRBP/RPAP3 interaction. First, we confirmed the interaction both in vitro and in vivo and we identified the TRBP and RPAP3 domains involved in the interaction, as well as several interesting mutations in the binding interface. Using these mutants should allow us to study the effects of this mutations on the maturation of differents ncRNAs. Additionally, we showed that the interaction between TRBP and RPAP3 and between TRBP and the RNase Dicer were mutually exclusive. Interestingly, it was shown that in the absence of TRBP, Dicer processig resulted, in some cases, in the generation of microRNAs with different ends, and thus, with altered specificity(iso-miRs). The interaction between TRBP and RPAP3 could therefore also constitute a possible way to regulate the availability of TRBP, and eventually the activity of Dicer

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Nadimpalli, Hima Priyanka 1988. „Insights into cytoplasmatic polyadenylation mediated by Drosophila Dicer-2“. Doctoral thesis, Universitat Pompeu Fabra, 2017. http://hdl.handle.net/10803/664810.

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Cytoplasmic polyadenylation is a widespread mechanism to control mRNA translation. In vertebrates, this mechanism requires two sequence elements in the 3’ UTR of substrate mRNAs, the U-rich Cytoplasmic Polyadenylation Element (CPE) and the AAUAAA polyadenylation hexanucleotide (HN). In Drosophila early embryos, the cytoplasmic polyadenylation of Toll mRNA occurs independently of these elements, and requires Dicer-2, a factor previously known for its functions in RNA interference (RNAi), in addition to the poly(A) polymerase Wispy. To understand this novel function of Dicer-2 in cytoplasmic polyadenylation and translation, we aimed to dissect the required cisacting requirements in Toll mRNA, and to identify Dicer-2 protein partners and mRNA targets. We found that multiple signals in the 3’ UTR of Toll cooperate for polyadenylation, and that in early embryos the non-canonical signals dominate, probably due to the presence of inhibitory elements for canonical polyadenylation. Interactome analysis using affinity purification of Dicer-2 and mass spectrometry revealed that Dicer-2 interacts with multiple proteins outside the RNAi pathway. Importantly, proteins involved in poly(A) tailmediated translational regulation and PABP binding were identified, suggesting potential co-factors of Dicer-2 in polyadenylation. Furthermore, RIP-Seq analysis of Dicer-2 revealed enrichment of mRNAs which were previously found downregulated in wispy mutants. These results suggest that the role of Dicer-2 in cytoplasmic viii polyadenylation might be widespread, and provide the basis for future investigation.
La poliadenilación citoplasmática es un mecanismo de control de la traducción extendido a lo largo de la escala animal. En vertebrados, este mecanismo requiere dos secuencias en el extremo 3’ no traducido (UTR) del mRNA, el elemento de poliadenilación citoplasmática rico en uridinas (CPE) y el hexanucleótido de poliadenilación AAUAAA (HN). En embriones tempranos de Drosophila, la poliadenilación de Toll, sin embargo, ocurre independientemente de estas secuencias, y requiere al menos dos factores: Dicer-2, una proteína previamente implicada en interferencia de RNA (RNAi), y la poly(A) polimerasa Wispy. Para entender esta nueva función de Dicer-2 en poliadenilación citoplasmática y traducción, nos propusimos diseccionar los elementos en el extremo 3’ UTR de Toll relevantes para este mecanismo de poliadenilación no canónica, así como identificar proteínas y mRNAs que interaccionan con Dicer-2 a gran escala. Nuestros resultados indican que el extremo 3’ UTR de Toll contiene varias secuencias implicadas en poliadenilación, y que el mecanismo no canónico es dominante en embriones tempranos, probablemente porque los elementos canónicos (CPE y HN) se encuentran activamente reprimidos. El estudio del interactoma de Dicer-2, realizado por purificación por afinidad e identificación por espectrometría de masas, reveló numerosas proteínas que no están implicadas en RNAi. Entre ellas, encontramos factores previamente relacionados con control de la longitud del poly(A) o con interacción con PABP y traducción, sugiriendo que estos factores podrían actuar x como co-factores de Dicer-2 en poliadenilación citoplasmática. Análisis de mRNA targets mediante RIP-Seq reveló multiples tránscritos que previamente fueron identificados como targets de Wispy. Estos resultados sugieren una función extendida de Dicer-2 en poliadenilación citoplasmática, y establecen una base sólida para investigaciones futuras.

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Engl, Johanna Pia Magdalena. „Festigkeit und Dicke des hyalinen Knorpels am equinen Talus“. Giessen : VVB Laufersweiler, 2007. http://geb.uni-giessen.de/geb/volltexte/2007/4748/index.html.

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Wong, Pui Man. „The role of Dicer and microRNAs in lymphocyte development“. Thesis, University of Cambridge, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.608452.

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張礎恆 und Chor-hang Paul Cheung. „Solutions of wormhole in the generalized Brans-Dicke theory“. Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B31215075.

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Matusiak, Raphaël. „TWEAK : un nouveau régulateur de la ribonucléase III Dicer“. Thesis, Université Laval, 2014. http://www.theses.ulaval.ca/2014/30612/30612.pdf.

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La répression de la traduction des ARN messagers (ARNm) par les microARN est un processus qui régule environ 60% de tous les gènes chez l’humain et module la quasi-totalité des processus biologiques cellulaires. La ribonucléase Dicer étant l’enzyme responsable de la conversion des précurseurs de microARN en microARN matures, nous nous attendons à ce que le maintien de l’homéostasie cellulaire dépende d’une régulation fine des niveaux d’expression et de l’activité enzymatique de Dicer. L’utilisation du double-hybride chez la levure nous a permis d’identifier la protéine Tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK), comme un partenaire potentiel de la forme humaine de Dicer. TWEAK est un membre de la famille des TNF qui a été découvert récemment et qui est impliqué dans de nombreux processus biologiques, dont l’inflammation. Produit majoritairement par les leucocytes, son expression protéique est altérée dans de nombreuses maladies, dont l’arthrite rhumatoïde. L’objectif de notre étude vise donc à déterminer la nature, l’implication et le rôle de l’interaction entre Dicer et TWEAK dans le processus inflammatoire. Nous avons confirmé l’interaction Dicer-TWEAK par co-immunoprécipitation et leur colocalisation par immunofluorescence dans la lignée cellulaire HEK293. Nous avons également documenté un effet inhibiteur de TWEAK sur la capacité enzymatique de Dicer à produire des microARN matures in vitro et dans les cellules HEK293. Cette étude permet de mieux comprendre les mécanismes régulatoires de l’activité de Dicer et de l’expression des microARN dans le processus inflammatoire.

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Camargo, Junior Fausto de. „Manifestações do caos no modelo do Maser de Dicke“. [s.n.], 1995. http://repositorio.unicamp.br/jspui/handle/REPOSIP/278173.

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Orientador: Kyoko Furuya
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica "Gleb Wataghin"
Made available in DSpace on 2018-07-20T20:04:37Z (GMT). No. of bitstreams: 1 CamargoJunior_Faustode_D.pdf: 1635813 bytes, checksum: 4d841d15f27c1e5659a76531036222c7 (MD5) Previous issue date: 1995
Resumo: Estudamos os efeitos da não-integrabilidade no modelo do Maser de Dicke, através da observação nas alterações dos padrões de distribuições de valores esperados nos auto-estados de energia de alguns operadores relevantes ao sistema, graficados contra os autovalores de energia. A densidade de estados semiclássica e os valores médios de observáveis, do ponto de vista do ensemble microcanônico, são obtidos e comparados com o padrão de distribuição dos valores médios quânticos com uma boa concordância tanto no caso regular como no caso com caos. A análise das flutuações em torno dos valores médios semiclássicos são feitas através de seções de Poincaré clássicas e mostramos evidências de que existe uma conexão com o comportamento das órbitas periódicas clássicas e suas estabilidades. Calculamos também, na aproximação de campo médio, grandezas termodinâmicas, como o calor específico para o modelo como função da temperatura. Esta função mostra uma descontinuidade com a temperatura de transição de fase superradiante Tc, para interações suficientemente forte, e também o fato de que este resultado não é sensível à presença do caos. A análise dos pontos fixos da dinâmica à temperatura finita é feita tanto para o caso regular como para o caso com caos, e a estabilidade das soluções são discutidas
Abstract: We study the effects of nonintegrability in the Dicke Maser Model by observing the modifications in the patterns of distribution of expectation values in the energy eigenstates of some selected operators plotted against energy eigenvalues. The semiclassical density of states and the mean values of observables in the microcanonical ensemble are obtained and compared with the quantum plots with a very good agreement for both regular and chaotic case. Analysis of fluctuations around the semiclassical mean values are made by means of classical Poincaré sections, and evidences of its connections with the behaviour of the classical periodic orbits and their stabilities are shown. We have also calculated, in the mean field approximation, the quantities like the specific heat of the model as a function of the temperature. Such a function displays a discontinuity at the superradiant transition temperature Tc for large enough interaction, and the fact that this result is not sensitive to the presence of chaos. The fixed point analysis of the dynamics at finite temperature is done for regular and chaotic cases and their stability conditions are discussed.
Doutorado
Física
Doutor em Ciências

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MORENO, FILHO Marcos George Magalhães. „Dicke states: production from EPR pairs and entanglement analysis“. Universidade Federal de Pernambuco, 2017. https://repositorio.ufpe.br/handle/123456789/27714.

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In this work we analyze the problem of creation of Dicke states through the process of entanglement swapping. First we deal with the tripartite case, presenting a deterministic protocol based on a source of EPR pairs. Still in this topic we show that it is possible to create perfect W states (tripartite Dicke states), even when the EPR source does not yield maximally entangled pairs, with a finite success rate. Subsequently we cope with the n-partite case, for which we present a probabilistic procedure, also employing EPR-pair sources, where the output, whenever successful, is perfect. The analysis of this protocol reveals a critical transition for the success probability, which is characterized in the framework of Landau theory of second order phase-transitions. Finally we proceed with a study of the entanglement between bipartitions of systems described by Dicke states, which allows for the implementation of entanglement witnesses. For each Dicke state we present a highly sensitive witness.
Neste trabalho analisamos o problema de criação de estados de Dicke através de um processo de entanglement swapping. Inicialmente tratamos o caso tripartite, para o qual apresentamos um protocolo determinístico empregando uma fonte de estados EPR. Ainda nesse tópico, mostramos que, com uma taxa de sucesso finita, é possível produzir estados W (estados de Dicke tripartite) perfeitos mesmo quando utilizamos uma fonte de estados EPR não maximamente emaranhados. Em seguida consideramos o caso de n partes, para o qual apresentamos um procedimento probabilístico, também fazendo uso de uma fonte de estados EPR, em que o resultado, sempre que bem-sucedido, é perfeito. A análise deste protocolo revela uma transição crítica, que é caracterizada no contexto da teoria de transição de fase de segunda ordem de Landau. Por ultimo fazemos um estudo do emaranhamento entre bipartições de sistemas descritos por estados de Dicke, que nos permite a implementação de testemunhas de emaranhamento. Para cada estado de Dicke, apresentamos uma testemunha com alta sensibilidade.

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Silva, João de Ribamar. „Gravitacionismo no contexto da teoria gravitacional de Brans-Dicke“. Universidade Federal de Roraima, 2010. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=63.

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In this work we develop the formalism of the gravitomagnetism in the context of the Brans-Dicke theory of gravity. We write the field equations in a type-Maxwell form while considering the approximations of weak field and of low speed of rotation of the source. We examine the effect of Lense-Thirring precession of inertial frames and obtained the equation of motion for a particle. We have also introduced a model with the angular momentum of the source varying linearly with time, calculating the gravitomagnetic time delay due. The results were compared with the predictions of the theory of General Relativity.
Neste trabalho desenvolvemos o formalismo do gravitacionismo no contexto da teoria gravitacional de Brans-Dicke. Escrevemos as equações de campo em uma forma tipo-Maxwell ao considerarmos as aproximações de campo fraco e de baixa velocidade de rotação da fonte. Examinamos o efeito Lense-Thiring de pressão dos referenciais inerciais e obtivemos a equação de movimento para uma partícula. Introduzimos ainda um modelo com o momento angular da fonte variando linearmente no tempo, calculando o atraso do tempo gravitomagnético decorrente. Os resultados obtidos foram comparados com as previsões da teoria da Relatividade Geral.

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Weiss, Andreas. „Le diacre permanent dans le diocese de rotenburg-stuttgart“. Université Marc Bloch (Strasbourg) (1971-2008), 1990. http://www.theses.fr/1990STR20046.

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Stowe, Heather Marguerite. „Cloning and expression of porcine Dicer and Argonaute-2“. Connect to this title online, 2009. http://etd.lib.clemson.edu/documents/1263408510/.

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Cheung, Chor-hang Paul. „Solutions of wormhole in the generalized Brans-Dicke theory /“. Hong Kong : University of Hong Kong, 1998. http://sunzi.lib.hku.hk/hkuto/record.jsp?B19737968.

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Yamanaka, Laís Eiko. „Caracterização da DICER-LIKE 2 (TrDCL2) de Trypanosoma rangeli“. reponame:Repositório Institucional da UFSC, 2016. https://repositorio.ufsc.br/xmlui/handle/123456789/168303.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Biológicas, Programa de Pós-Graduação em Biotecnologia e Biociências, Florianópolis, 2016.
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O mecanismo de RNA de interferência (RNAi) é um sistema pós-transcricional de silenciamento gênico com ampla distribuição nos organismos eucariotos. Os pequenos RNA (siRNA e miRNA) são considerados moléculas chaves nesse mecanismo, os quais são gerados pela proteína Dicer. A presença desse sistema parece não seguir um padrão de distribuição filogenético e a sua evolução ainda não foi compreendida. Entre os protozoários, o mecanismo de RNAi está muito bem caracterizado em Trypanosoma brucei, entretanto é ausente em Trypanosoma cruzi e em muitas espécies de Leishmania. O Trypanosoma rangeli não possui vários componentes da maquinaria de RNAi, tornando-a não funcional. Entretanto, o gene que codifica para a Dicer- Like2 (DCL2) foi encontrado completo em seu genoma, enquanto os demais genes codificantes para as outras proteínas da maquinaria estão truncados (pseudogenes). No presente estudo realizamos a caracterização do gene DCL2 de T. rangeli (TrDCL2), o qual apresentou-se como cópia única no genoma do parasito, possuindo uma janela aberta de leitura com 2.667 pb que codifica para uma proteína de 889 aminoácidos (±100 kDa). Foram reveladas diferenças nas sequências aminoacídicas da TrDCL2 entre as cepas KP1(+) e KP1(-) de T. rangeli e devido uma mudança na fase de leitura não é possível identificar os domínios RNAse III nas cepas KP1(-). O gene TrDCL2 é transcrito nas cepas KP1(+), sendo que os níveis de mRNA não apresentam alterações significativas durante o processo de diferenciação celular in vitro do parasito. Visando a avaliação da atividade enzimática e análise da presença e níveis proteicos, realizamos a expressão heteróloga de dois fragmentos e da proteína TrDCL2 inteira. Um dos fragmentos foi utilizado para a produção de um antissoro policlonal anti-TrDCL2. Este antissoro reconheceu uma proteína do tamanho esperado (±100 kDa) nos extratos proteicos totais das formas epimastigotas e tripomastigotas de T. rangeli. Os ensaios de imunofluorescência indireta, utilizando o mesmo antissoro, revelaram uma distribuição difusa da proteína pelo citoplasma de ambas as formas do parasito. A TrDCL2 é expressa em algumas cepas do T. rangeli, entretanto a determinação do seu papel biológico neste parasito ainda permanece a ser elucidada.

Abstract : The interference RNA mechanism (RNAi) is a system of post-transcriptional gene silencing with wide distribution in the eukaryotes. Small RNA (siRNA e miRNA) are considered key molecules in this mechanism, which are generated by Dicer protein. The presence of this system seems not follow a pattern of phylogenetic distribution and its evolution is still not understood. Between trypanosomatids, the RNAi mechanism is well described in Trypanosoma brucei, but is absent in Trypanosoma cruzi and some Leishmania species. Trypanosoma rangeli does not have many components of RNAi machinery, making it not functional. However, the Dicer-Like2 (DCL2) coding gene was fully encountered in its genome, while the other genes of this machinery are truncated (pseudogenes). In the present study, we have realized the characterization of DLC2 gene of T. rangeli (TrDCL2), which presented a single copy in the parasite genome, having an open reading frame with 2.667 bp that encodes a protein with 889 amino acids (±100 kDa). Differences in aminoacidic sequences were revealed between strains KP1(+) and KP1(-) of T. rangeli and due to a change in the reading phase it was not possible to identify RNAse III domains in the KP1(-) strains. TrDCL2 gene is transcripted in the KP1(+), the mRNA levels do not show significant alterations during the process of cellular differentiation in vitro. Aiming the evaluation of the enzymatic activity and the analysis of the presence of the protein and its levels, we realized the heterologous expression of two fragments and the whole protein TrDCL2. One of the fragments was used to produce a polyclonal antiserum anti-TrDCL2. This antiserum recognized a protein with the expected size (±100 kDa) in the total protein extracts of the epimastigotes and trypomastigotes of T. rangeli. Imunofluorescence assays, using the same antiserum, revealed a diffuse distribution of the protein in the cytoplasm in both forms of the parasite. The TrDCL2 is expressed in some strains of T. rangeli, but the determination of its biological role in this parasite still needs to be elucidated.

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Pelegri, Kristic Andrea Paz. „Approche fonctionnaliste de la langue au théâtre. Pour une version chilienne du Chant du Dire-Dire de Daniel Danis“. Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20487.

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L’étude proposée accompagne une traduction en espagnol d’un extrait du Chant du Dire-Dire de Daniel Danis en vue d’une production de la pièce par la compagnie Tiatro à Santiago du Chili. La méthodologie utilisée s’appuie sur la théorie fonctionnaliste du skopos (Vermeer 1978). Celle-ci envisage chaque traduction comme un acte de communication à part entière, indépendant de celui du texte source, puisqu’elle est destinée à un système socio-culturel différent et ainsi s’adresse à des usagers différents ; d’où la nécessité de soumettre le dispositif du texte source à ces nouveaux paramètres au moment d’établir le « projet » de la traduction. Cette approche fonctionnaliste remet en question le caractère prescriptif de certains concepts proposés pour traduire le théâtre, comme celui de « playability », « performability » ou de « théâtralité ». On constate que ces notions sont trop ambiguës et ne tiennent pas compte des particularités esthétiques de chaque pièce ou du contexte de la représentation. L’établissement du skopos, c’est-à-dire de l’objectif de notre propre traduction destinée à un public chilien, repose principalement sur une analyse dramaturgique et esthétique de la pièce de Danis. Les particularités du texte sont décrites, en particulier, le traitement de la langue, qui constitue le principal défi de la traduction. Celle-ci est étudiée dans ses rapports avec le théâtre québécois de « l’époque du joual » et avec l’oralité populaire pour cerner une singularité porteuse du projet dramaturgique de l’auteur. L’étude détaillée de la pièce est suivie d’une traduction commentée d’un « dire » intitulé Les traces du chaos dans la maison Durant. Cette traduction est présentée sous forme bilingue et accompagnée d’un commentaire explicitant les problèmes rencontrés et les solutions micro-structurelles proposées en fonction du skopos préalablement établi. The present research complements a Spanish translation of an excerpt of Daniel Danis’ Le Chant du Dire-Dire (Song of the Say-Sayer) for a future production by the theatre company Tiatro in Santiago de Chile. The methodology is based on Vermeer’s skopos theory (1978), a functionalist approach to translation. This theory considers every translation an independent communicational act, different from the one established by the source text since it is destined to a different socio-cultural system and thus, different users. As such, it is necessary to adapt the source text system to these new parameters when defining the translation “project”. This functionalist approach puts into question some of the best known concepts advanced in theatre translation during the past twenty years, such as “playability”, “performability” or “theatricality”. They prove too vague and do not take into considering the aesthetic specificities of each play or the context to which they are destined. The parameters of the skopos, in the present case, that of a translation intended to be performed in front of a Chilean audience, is based on a detailed analysis of Danis’ play. This analysis defines the unique attributes of the text, specifically in regards to the use of language. The research also examines the relationship between the play’s language and the “époque du joual” (1960-1970’s) in québécois theatre, as well as its rapport with québécois vernaculars, insofar as they are key in the articulation of the playwright’s dramaturgical project. The analysis of the play is followed by an annotated translation of the “dire” entitled Les traces du chaos dans la maison Durant (Traces of chaos in the Lasting home). This translation, presented in a bilingual format, provides commentary explaining the different problems encountered during the process as well as the micro-structural adaptations proposed according to the pre-established skopos.

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Shamandi, Nahid. „Functional analysis of plant RNaseIII enzymes“. Thesis, Paris 11, 2013. http://www.theses.fr/2013PA112157/document.

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Chez la majorité des eucaryotes, les petits ARN (miRNA et siRNA) jouent des rôles essentiels au cours du développement, dans les réponses adaptatives aux stress, et dans la maintenance de la stabilité génétique. Les plantes codent quatre enzymes RNaseIII de type DICER-LIKE (DCL). DCL1, produit les miRNAs, tandis que DCL2, DCL3 et DCL4 produisent des siRNAs des tailles diverses. Les plantes codent également des enzymes appelées RNASE-THREE-LIKE (RTL) auxquelles il manque certains domaines spécifiques aux DCLs, et dont la fonction est largement inconnue.Des plantes sur-exprimant RTL1 montrent des défauts morphologiques, et n'accumulent pas les siRNAs produits par DCL2, DCL3 ou DCL4, indiquant que RTL1 est un suppresseur général des voies de siRNA chez les plantes. L’activité de RTL1 nécessite un domaine RNaseIII fonctionnel. RTL1 ne s'exprime naturellement que faiblement dans les racines, mais l'infection virale induite fortement son expression dans les feuilles, ce qui suggère que l’induction de RTL1 est une stratégie générale utilisée par les virus pour contrer la défense antivirale basée sur siRNAs. En accord avec cette hypothèse, les plantes transgéniques sur-exprimant RTL1 sont plus sensibles à l'infection par le TYMV que des plantes de type sauvage, probablement parce que RTL1 empêche la production des siRNAs dirigés contre les RNA viraux. Cependant, les plantes transgéniques sur-exprimant RTL1 ne sont pas plus sensibles à l'infection par le TCV, TVCV ou le CMV, qui codent les suppresseurs de RNA silencing (VSR) plus puissants que le TYMV. En effet, le VSR de TCV inhibe l'activité de RTL1, suggérant que l'induction de l’expression de RTL1 par les virus et l’amortissement de l’activité de RTL1 par leurs VSRs est une double stratégie permettant d’établir une infection avec succès. Des plantes sur-exprimant RTL2 ou des mutants rtl2 ne montrent aucun défaut morphologique, et ne montrent pas de changement majeur du répertoire des petits ARNs endogènes. Toutefois, la sur-expression de RTL2 augmente l’accumulation des petits ARNs exogènes dans des essais d’expression transitoire, et cette activité nécessite un domaine RNaseIII fonctionnel. Il est donc possible que RTL2 clive certains substrats pour faciliter l’action des enzymes DCL
Small RNAs, including miRNA and siRNA, play essential regulatory roles in genome stability, development and stress responses in most eukaryotes. Plants encode four DICER-LIKE (DCL) RNaseIII enzymes. DCL1 produces miRNAs, while DCL2, DCL3 and DCL4 produce diverse size classes of siRNA. Plants also encode RNASE THREE-LIKE (RTL) enzymes that lack DCL-specific domains and whose function is largely unknown. Arabidopsis plants over-expressing RTL1 exhibit morphological defects and lack all types of small RNAs produced by DCL2, DCL3 and DCL4, indicating that RTL1 is a general suppressor of plant siRNA pathways. RTL1 activity requires a functional RNaseIII domain. RTL1 is naturally expressed only weakly in roots, but virus infection strongly induces its expression in leaves, suggesting that RTL1 induction is a general strategy used by viruses to counteract the siRNA-based plant antiviral defense. Accordingly, transgenic plants over-expressing RTL1 are more sensitive to TYMV infection than wild-type plants, likely because RTL1 prevents the production of antiviral siRNAs. However, TCV, TVCV and CMV, which encode stronger suppressors of RNA silencing (VSR) than TYMV, are insensitive to RTL1 over-expression. Indeed, TCV VSR inhibits RTL1 activity, suggesting that inducing RTL1 expression and dampening RTL1 activity is a dual strategy used by viruses to establish a successful infection. Plants over-expressing RTL2 and rtl2 mutants do not exhibit morphological defects and do not show major changes in the endogenous small RNA repertoire. However, RTL2 over-expression enhances the accumulation of exogenous siRNAs in transient assays, and this activity requires a functional RNaseIII domain. Therefore, it is possible that plant RTL2 processes certain substrates to facilitate the action of DCL enzymes

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Dissertationen zum Thema „DiCre“

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