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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
171

Indirect Bonding Method: in vitro Comparison of the Shear Bond Strength between Metallic Orthodontic Brackets and Different Porcelain Surface Preparations

Mai, Stéphanie H. 04 1900 (has links)
Introduction : La force d’adhésion à l'interface métal-céramique avec les résines auto-polymérisantes destinées au collage indirect des boîtiers orthodontiques n'a pas été évaluée à ce jour et un protocole clinique basé sur la littérature scientifique est inexistant. Objectifs : 1) Comparer la force de cisaillement maximale entre des boîtiers métalliques et des surfaces en porcelaine préparées selon différentes méthodes; 2) Suggérer un protocole clinique efficace et prévisible. Matériel et méthodes : Quatre-vingt-dix disques en leucite (6 groupes; n = 15/groupe) ont été préparés selon 6 combinaisons de traitements de surface : mécaniques (+ / - fraisage pour créer les rugosités) et chimiques (acide fluorhydrique, apprêt, silane). Des bases en résine composite Transbond XT (3M Unitek, Monrovia, California) faites sur mesure ont été collées avec le système de résine adhésive auto-polymérisante Sondhi A + B Rapid Set (3M Unitek, Monrovia, California). Les échantillons ont été préservés (H2O/24hrs), thermocyclés (500 cycles) et testés en cisaillement (Instron, Norwood, Massachusetts). Des mesures d’Index d’adhésif résiduel (IAR) ont été compilées. Des tests ANOVAs ont été réalisés sur les rangs étant donné que les données suivaient une distribution anormale et ont été ajustés selon Tukey. Un Kruskall-Wallis, U-Mann Whitney par comparaison pairée et une analyse de Weibull ont aussi été réalisés. Résultats : Les médianes des groupes varient entre 17.0 MPa (- fraisage + acide fluorhydrique) à 26.7 MPa (- fraisage + acide fluorhydrique + silane). Le fraisage en surface ne semble pas affecter l’adhésion. La combinaison chimique (- fraisage + silane + apprêt) a démontré des forces de cisaillement significativement plus élevées que le traitement avec (- fraisage + acide fluorhydrique), p<0,05, tout en possédant des forces similaires au protocole typiquement suggéré à l’acide fluorhydrique suivi d’une application de silane, l’équivalence de (- fraisage + acide fluorhydrique + silane). Les mesures d’IAR sont significativement plus basses dans le groupe (- fraisage + acide fluorhydrique) en comparaison avec celles des 5 autres groupes, avec p<0,05. Malheureusement, ces 5 groupes ont des taux de fracture élévés de 80 à 100% suite à la décimentation des boîtiers. Conclusion : Toutes les combinaisons de traitement de surface testées offrent une force d’adhésion cliniquement suffisante pour accomplir les mouvements dentaires en orthodontie. Une application de silane suivie d’un apprêt est forte intéressante, car elle est simple à appliquer cliniquement tout en permettant une excellente adhésion. Il faut cependant avertir les patients qu’il y a un risque de fracture des restorations en céramique lorsque vient le moment d’enlever les broches. Si la priorité est de diminuer le risque d’endommager la porcelaine, un mordançage seul à l’acide hydrofluorique sera suffisant. / Background : Bond strength at the metal-ceramic interface of auto-polymerizing resins used in orthodontic indirect bonding has not yet been evaluated and a literature-based clinical protocol is lacking. Goals : 1) To compare shear bond strength (SBS) between metal brackets and differently treated porcelain surfaces; 2) To suggest efficient and predictable chairside approaches. Materials and methods : Ninety leucite discs (6 groups; n=15/group) were prepared following 6 combinations of mechanical (+/- bur roughening) and chemical (hydrofluoric acid, primer, silane) treatments. Metal brackets with custom composite resin Transbond XT (3M Unitek, Monrovia, California) bases were bonded with the adhesive resin system Sondhi A+B Rapid Set (3M Unitek, Monrovia, California). Samples were stored (H2O/24hrs), thermocycled (500 cycles) and tested (Instron, Norwood, Massachusetts). Maximum SBS and adhesive remnant index (ARI) scores were collected for each sample. ANOVAs were performed on ranks since data was not normally distributed, and then adjusted with the post-hoc Tukey method. A Kruskall-Wallis, a Mann Whitney U pairwise comparison and a Weibull analysis were also performed. Results : SBS medians of groups ranged from 17.0 MPa (- bur + hydrofluoric acid) to 26.7MPa (- bur + hydrofluoric acid + silane). Bur roughening did not affect bond strength. The chemical preparation of (- bur + primer + silane) showed statistically significant higher SBS than (- bur + hydrofluoric acid) preparation (p<0,05), while having similar SBS to the popular recommended protocol (- bur + hydrofluoric acid + silane). ARI scores were statistically significant lower in group (- bur + hydrofluoric acid) with p<0,05, while all other 5 groups were not different from each other. Percentage of porcelain damage in these 5 groups were very high at 80-100%. Conclusion : All the tested surface preparations combinations provided clinically adequate adhesion for orthodontic tooth movement. A silane and primer combination for porcelain surface preparation is clinically attractive as it is safe and simple and provides great adhesion for orthodontic tooth movement. It is wise to warn patients that there is a risk of porcelain fractures when debonding brackets. If one prefers to avoid porcelain fracture at all cost, one may treat porcelain with hydrofluoric acid only.
172

DOCUMENT DE SYNTHÈSE : Parcours critique, position théorique et perspectives de recherche

De Mattia-Viviès, Monique 10 December 2004 (has links) (PDF)
Ce rapport de synthèse retrace mon parcours d'enseignement et de recherche, et expose ma position théorique et mes perspectives de recherche
173

Accounting for mean flow effects in a zero-Mach number thermo-acoustic solver : application to entropy induced combustion instabilities / Prise en compte des effets d'écoulement moyen dans un solveur thermo-acoustique sous l'hypothèse Mach nul : application aux instabilités de combustion induites par l'entropie

Motheau, Emmanuel 15 November 2013 (has links)
Pratiquement toutes les chambres de combustion présentent des instabilités. Par conséquent, il est nécessaire de mieux les comprendre afin de les contrôler. Une possibilité est de simuler l’écoulement réactif à l’intérieur d’une chambre de combustion grâce à la Simulation aux Grandes Echelles (SGE). Cependant la SGE est très coûteuse en terme de capacité de calcul. Une autre possibilité est de réduire la complexité du problème à une simple équation d’onde thermoacoustique (équation dite de Helmholtz), qui peut être résolue en fréquence comme un problème aux valeurs propres. Le couplage entre l’acoustique et la flamme est alors prise en compte au travers des modèles appropriés. Le principal problème de cette méthode est qu’elle repose sur l’hypothèse d’un nombre de Mach nul. Tous les phénomènes liés à l’écoulement moyen sont donc négligés. La présente thèse propose une nouvelle stratégie pour prendre en compte certains effets de l’écoulement dans un contexte à Mach nul. Dans une première partie, la manière la plus judicieuse d’imposer un élément présentant un écoulement très rapide est étudiée. La seconde partie se focalise sur le couplage entre l’acoustique et les hétérogénéités de température qui sont générées par la flamme et naturellement convectées par l’écoulement moyen. Ce phénomène est important car il est responsable du bruit indirect de combustion qui peut conduire à une instabilité thermoacoustique. Un nouveau type de condition limite (DECBC) est proposé afin de prendre en compte ce mécanisme dans un contexte de résolution de l’équation de Helmholtz à Mach nul. Dans la dernière partie, une chambre de combustion aéronautique présentant une instabilité mixte acoustique/entropique est étudiée. Le bénéfice des méthodes développées dans la présente thèse est testé et comparé à des calculs avec la SGE. Il est montré que les calculs avec un solveur de Helmholtz peuvent reproduire une instabilité de combustion complexe, et que cet outil s’avère avoir le potentiel pour prédire les instabilités afin de concevoir de nouvelles chambres de combustion. / Virtually all combustion chambers are subject to instabilities. Consequently there is a need to better understand them so as to control them. A possibility is to simulate the reactive flow within a combustor with the Large-Eddy Simulation (LES) method. However LES results come at a tremendous computational cost. Another route is to reduce the complexity of the problem to a simple thermoacoustic Helmholtz wave equation, which can be solved in the frequency domain as an eigenvalue problem. The coupling between the flame and the acoustics is then taken into account via proper models. The main drawback of this latter methodology is that it relies on the zero-Mach number assumption. Hence all phenomena inherent to mean flow effects are neglected. The present thesis aims to provide a novel strategy to introduce back some mean flow effects within the zero-Mach number framework. In a first part, the proper way to impose high-speed elements such as a turbine is investigated. The second part focuses on the coupling between acoustics and temperature heterogeneities that are naturally generated at the flame and convected downstream by the flow. Such phenomenon is important because it is responsible for indirect combustion noise that may drive a thermoacoustic instability. A Delayed Entropy Coupled Boundary Condition (DECBC) is then derived in order to account for this latter mechanism in the framework of a Helmholtz solver where the baseline flow is assumed at rest. In the last part, a realistic aero-engine combustor that features a mixed acoustic/entropy instability is studied. The methodology developed in the present thesis is tested and compared to LES computations. It is shown that computations with the Helmholtz solver can reproduce a complex combustion instability, and that this latter methodology is a potential tool to design new combustors so as to predict and avoid combustion instabilities.
174

Développement d'une machine de fatigue gigacyclique en torsion pour les matériaux métalliques à haute résistance / Development of a torsional gigacyclic fatigue machine for high-strength metallic materials

Jiang, Zhaoyi 10 January 2018 (has links)
Ce travail de recherche donc concerne l'étude du système ultrasonique de fatigue en torsion de type indirect pouvoir étudier le comportement des matériaux métalliques à haute résistance, essentiellement au domaine de fatigue gigacyclique. Il existe actuellement deux types de système ultrasonique de torsion : un système qualifié de "direct" dans lequel le convertisseur délivre une rotation permettant, de manière simple et directe, la mise en vibration de torsion du système ; un système qualifié de "indirect" qui utilise un convertisseur longitudinal et nécessite une transformation en rotation pour créer la vibration en résonance de torsion. Premièrement, la présente d'étude sur le système indirect permet de comprendre son comportement de fatigue et ses propriétés. Cette étude est présentée à partir des calculs analytiques et numériques afin de dimensionner et modéliser ce système. Ensuite, l'optimisation du système à l'aide de la méthode des éléments finis est réalisée et un système plus effectif et plus robuste est obtenu. Des comparaisons entre les résultats numériques et les résultats de calibration sont proposées et une interprétation des écarts constatés est proposée avec les nouvelles simulations numériques. Deuxièmement, une campagne expérimentale à 20 kHz au-delà de 10⁸ cycles est menée en utilisant le système optimisé sur les aciers 16MnCr5 et 50CrV4 du projet FreqTigue. La méthode de l'escalier est utilisé dans les essais afin de décrire la courbe S-N, d'estimer la résistance à la fatigue et d'obtenir la durée de vie en fatigue. Des comparaisons des courbes S-N à différentes fréquences et sollicitations sont présentées. Les surfaces de rupture des éprouvettes sont analysées pour tenter d'identifier les causes de la rupture. / This research work concerns the study of the torsional ultrasonic fatigue system of indirect type which is able to study the behavior of high-strength metallic materials, mainly in the domain of gigacyclic fatigue. With the developments of technique, there are currently two types of ultrasonic torsional system: the first one is described as "direct" and its converter delivers a rotation which allows the system vibrate in torsion; the second one is described as "indirect", which uses a longitudinal converter and requires the transformation of a translation into a rotation to create a desired torsional resonant vibration in the specimen. Firstly, the study of the indirect system could understand the fatigue behavior and the properties of this system. This study is presented with the analytical and numerical calculations in order to determine and model the indirect system. Then, the optimization of this system by using the finite element method is performed and a more efficient and robust system is developed. Some comparisons between the numerical results and calibration’s results are proposed and an interpretation of differences is proposed by using new numerical simulations. Secondly, the tests of the 16MnCr5 and 50CrV4 steels of the FreqTigue project are carried out at 20 kHz and beyond 10⁸ cycles by using this optimized system. The staircase method is used in the tests to describe the S-N curve, to estimate the fatigue strength and to obtain the fatigue life. Then, the comparisons of the S-N curves at different vibration frequencies and stresses are presented, and the ruptured surfaces of the specimen are also analyzed to identify the causes of the rupture.
175

Developmental and Functional Roles of Troponin-T Isoforms, and Exploring Genome-Wide Alterations in Drosophila Indirect Flight Muscle Mutants

Madan, Aditi January 2015 (has links) (PDF)
Muscle contraction is a highly fine-tuned process that requires the precise and timely construction of large protein sub-assemblies to form sarcomeres, the individual contractile units. Mutations in many of the genes encoding constituent proteins of this macromolecular machine result in defective functioning of the muscle tissue, and in humans, often lead to myopathic conditions like cardiomyopathies and muscular dystrophies, which affect a considerable number of people the world over. As more information regarding causative mutations becomes available, it becomes imperative to explore mechanisms of muscle development, maintenance and pathology. In striated muscles, contraction is regulated by the thin filament-specific tropomyosin (Tm) – troponin (Tn) complex (Ca2+-binding troponin-C, inhibitory troponin-I and tropomyosin-binding troponin-T). These troponin subunits are present in 1:1:1 ratio on thin filaments, with 1 Tm-Tn complex present on every 7th actin molecule. This stoichiometry is tightly regulated, and disturbances have been associated with functional defects. Each of these proteins has multiple isoforms, whose expression is controlled both spatially and temporally. The expression of specific combination of isoforms confers specific contractile properties to each muscle subtype. Drosophila melanogaster has been a preferred model of choice to study various aspects of muscle development for decades. In this study, the Indirect Flight Muscles (IFMs) of Drosophila have been used to investigate developmental and functional roles of two temporally regulated isoforms of a vital structural and regulatory component of the sarcomere – Troponin T (TnT). On a larger scale, whole genome expression profiles of mutants that are null for major myofbrillar proteins have also been discussed. IFMs serve as an excellent model system to address these questions, owing to the extreme ease of genetic manipulability in this system, and high degree of homology between mammalian and Dipteran cytoskeletal proteins. Chapter 1 covers basics of muscle biology, and the role of TnT in muscle contraction. Phenomena responsible for generating diversity in genes encoding muscle proteins – alternative splicing and isoform switching – have also been discussed. These mechanisms are highly conserved, as are patterns of TnT splicing and isoform expression across phyla. Mutations leading to altered splicing patterns lead to myopathic conditions, and the importance of model systems to study muscle biology has been emphasized. The advantages of studying Drosophila IFMs and a comprehensive overview of IFM development has been covered. The resources and experimental tools used have been described in Chapter 2. Two isoforms of TnT are alternatively spliced in the Drosophila thorax – one containing alternative exon 10a (expressed in adult IFMs and jump muscle); and one containing alternative exon 10b (expressed in pupae and newly eclosed flies). These exons are spliced in a mutually exclusive manner, and defects in splicing have been reported to cause uncontrolled, auto-destructive contractions. In Chapter 3, a splice mutant of TnT, up1, has been discussed, with respect to its developmental profile. Transgenic rescue experiments with two separate isoforms demonstrate rescue at the structural as well as functional level. Transgenic over-expression, however, leads to functional abnormalities, highlighting the importance of stoichiometry in multi-protein complexes. In Chapter 4, molecular signals that bring about the developmentally regulated TnT isoform switch are discussed. A splicing factor, Muscleblind, has been transgenically knocked down in normal and mutant IFMs to study effects on muscle function. Chapter 5 looks at whole genome transcriptional alterations in muscles null for either actin or myosin. All significant expression changes have been classified into categories based on different biological processes, and an attempt to differentiate generic muscle responses from filament-specific responses has been made. In conclusion, the studies have highlighted the importance of TnT isoform switching, and that extended expression of a pupal stage-specific isoform can partially compensate for loss of the adult isoform. Also, in the absence of major myofibrillar proteins, stress response pathways like heat shock response and protein degradation pathways are activated, along with a subset of metabolic responses that are unique to the thin or thick filament systems.
176

Les verbes à complément attributif en français et en arabe et leurs traductions / The verbs with attributive complement in french and in arabic and their translations

Al Yafi, Hanadi 21 October 2011 (has links)
La présente thèse relève à la fois de la linguistique et de la traduction. La traduction fait apparaître les similitudes et les différences sémantiques et syntaxiques entre les systèmes langagiers de la langue de départ et la langue d’arrivée. La traduction des verbes à compléments attributifs exige une connaissance approfondie de leur grammaire et de la syntaxe de leurs constructions. Une étude descriptive séparée de chaque langue présente un schéma syntaxique de ces verbes en français et en arabe. Cette thèse examine dans la dernière partie le cas du verbe kāna, verbe très important et de haute fréquence parmi les verbes à compléments attributifs étudiés. L’analyse portait sur le texte coranique. Une approche comparative montre que les équivalents de « kāna + préposition » trouvés dans la traduction de Blachère ne correspondent pas aux équivalents donnés par les dictionnaires et qu’il était impossible de traduire un verbe en se contentant de recourir à ces derniers, qui ne nous donnent pas toujours un équivalent parfait du verbe étudié et ne recouvrent pas tous les contextes possibles. En tant qu’exposant temporel ou verbe d’état, le verbe kāna doit être traduit d’après des indices contextuels (les marqueurs de la négation, modalités, préposition, …). Cette analyse indique clairement que le contexte immédiat et médiat du verbe joue un rôle primordial dans sa traduction comme on peut le voir avec le verbe kāna illustré par des exemples tirés du texte coranique. / This thesis pertains to both linguistics and translation studies. Translating from one language to another presents semantic and syntactic similarities and differences between Arabic and French. The translation of verbs with attributive complement demands a very good understanding of the grammar and of the syntactic constructions of the phrases containing these verbs. Separate studies of Arabic and French show a syntactical pattern of their verbs with attributive complement. This thesis also analyzes the use of the extremely important verb, kāna, the most frequently used between the Arabic verbs with an attribute studied in the corpus. We analysed its uses in the Coran. A close comparison shows that the equivalents of " kāna + preposition " that Blachère gives in his translation do not match with those found in dictionaries. In fact, translating this verb only with the definitions found in dictionaries is impossible. A dictionary as a single source will never be sufficient in the realm of translation. As a temporal exponent or a state verb, kāna must be translated by using contextual clues including (negation marker, modality, prepositions, …). This analysis clearly indicates that both direct and indirect contexts of a verb play an essential role in its translation. The verb, kāna, with its examples from the Coran documents this principle.
177

Estudo epidemiológico da coinfecção por toxoplasma gondii e pelo vírus da imunodeficiência felina em gatos domésticos (felis catus) em Goiânia, Goiás / Epidemiological study of the coinfection by toxoplasma gondii and by the feline immunodeficiency virus in domestic cats (felis catus) in Goiânia, Goiás

Costa, Rebeka Cristine de Bastos 25 August 2015 (has links)
Submitted by Cláudia Bueno (claudiamoura18@gmail.com) on 2016-01-14T16:38:41Z No. of bitstreams: 2 Dissertação - Rebeka Cristine de Bastos Costa - 2015.pdf: 2127820 bytes, checksum: 8789b51096d386c4def09d0d1ee4da0d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2016-01-15T09:55:51Z (GMT) No. of bitstreams: 2 Dissertação - Rebeka Cristine de Bastos Costa - 2015.pdf: 2127820 bytes, checksum: 8789b51096d386c4def09d0d1ee4da0d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2016-01-15T09:55:51Z (GMT). No. of bitstreams: 2 Dissertação - Rebeka Cristine de Bastos Costa - 2015.pdf: 2127820 bytes, checksum: 8789b51096d386c4def09d0d1ee4da0d (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-08-25 / Toxoplasmosis is a zoonotic disease in which mammals and birds can join the cycle as intermediate hosts, and felids as definitive hosts. Felis catus is recognized as the main responsible for the environmental contamination by Toxoplasma gondii oocysts. Serological diagnosis reveals little about the elimination of oocysts of T. gondii into the environment, principally by F. catus, which plays an important role in Public Health. There are few data on the frequency of feline toxoplasmosis in the State of Goiás. Therefore, the aim of this research was to evaluate the frequency of toxoplasmosis infection in domestic cats and their potential role in its transmission through the oocyst elimination into the environment and the respective factors associated with the infection. For this, we collected 102 blood samples and 98 fecal samples from 102 cats from Goiânia, State of Goiás. The animals were divided into groups according to age, gender and free access to the street or not. Indirect hemagglutination test was performed to determine the level of anti-T. gondii and indirect ELISA for the detection of infection by feline immunodeficiency virus (FIV). For search and detection of T. gondii oocysts elimination in the feces of cats we performed a centrifugal-flotation with Sheather's solution, subsequently we extracted DNA and used conventional PCR. The results showed that 18.63% (19/102) of the cats were positive for T. gondii, with titers ranging from 1:32 to 1: 8.192, while none of the fecal samples were positive in the PCR. The frequency of positive animals for FIV was 55.91% (52/93), and 18.28% (17/93) presented coinfection. By multivariate logistic regression we found the associated factors were the same for both infections, but one did not interfere with another. The factors associated with infection by T. gondii and feline immunodeficiency virus were free life and age under six months, since the sex was not statistically related to any of the illnesses. / A toxoplasmose é uma zoonose na qual, mamíferos e aves podem participar do seu ciclo como hospedeiros intermediários e os felídeos como hospedeiros definitivos. O Felis catus é reconhecido como o principal responsável pela contaminação ambiental por oocistos de Toxoplasma gondii. O diagnóstico sorológico pouco revela sobre a eliminação de tal fase no ambiente, o que representa o real impacto daquela espécie na Saúde Pública frente à toxoplasmose. São escassos os dados da frequência da toxoplasmose felina no Estado de Goiás. Assim sendo, objetivou-se com esta pesquisa avaliar a frequência da infecção da toxoplasmose em gatos domésticos e o seu potencial papel na sua transmissão, através da eliminação de oocistos no ambiente e dos respectivos fatores associados à infecção. Para isto, foram coletadas 102 amostras de sangue e 98 amostras fecais, de 102 gatos provenientes de Goiânia-Goiás. Os animais foram divididos em grupos de acordo com a faixa etária, gênero e livre acesso à rua ou não. Foi realizada a hemaglutinção indireta para a determinação do nível de anticorpos anti-T. gondii e o ELISA indireto para a detecção da infecção pelo vírus da imunodeficiência felina (FIV). Para a pesquisa e detecção da eliminação de oocistos de T. gondii nas fezes dos gatos foi feita a centrifugo-flutuação em solução de Sheather, posterior extração de DNA e realização da PCR convencional. Os resultados revelaram que 18,63% (19/102) dos gatos foram positivos para o T. gondii, com títulos variando entre 1:32 a 1:8.192, sendo que nenhuma das amostras fecais foi positiva na PCR. A frequência de positivos para o FIV foi de 55,91% (52/93), com coinfecção de 18,28% (17/93). Com a regressão logística multivariada verificou-se que os fatores associados foram os mesmos para as duas infecções, porém uma não interferiu diretamente na outra. Os fatores associados para a infecção pelo T. gondii e pelo vírus da imunodeficiência felina foram a vida livre e a idade igual ou superior a seis meses, já o gênero não apresentou relação estatística com nenhuma das enfermidades.
178

Le cose e i segni : per una semiotica dello stile indiretto libero nell'opera letteraria e cinematografica di Pier Paolo Pasolini / Les choses et les signes : une sémiotique du style indirect libre dans l'oeuvre littéraire et cinématographique de Pier Paolo Pasolini / Things and Signs : The free indirect style in the literary and cinematic works of Pier Paolo Pasolini

Desogus, Paolo 23 June 2015 (has links)
Cette thèse se propose d’étudier le style indirect libre dans l’œuvre de Pier Paolo Pasolini à travers un axe de recherche qui peut, schématiquement, se rattacher à deux champs: le champs poétique, concernant l'activité littéraire et cinématographique de l'auteur et le champs théorique, où le problème de la forme esthétique devient l'occasion pour l'étude des principes linguistiques etsémiotiques qui en permettent la réalisation. Ce double parcours s'articule à son tour en quatre phases de développement: la phase de la « régression » théorisée dans les années quarante pour expliquer divers processus relatifs à l’emploi du dialecte en littérature ; celle de la « connexion sentimentale », notion tirée des Cahiers de prison de Antonio Gramsci pour décrire le rapport entre les intellectuels et les classes subalternes ; celle du discours indirect libre en tant que tel, qui se trouve à la base de lapoétique des romans romains des années cinquante, et qui est également présent dans d’autres œuvres élaborées plus tard ; et finalement la phase de la subjective indirecte libre, théorisée dans les années soixante pour décrire le style indirect libre au cinéma.La régression, la connexion sentimentale, le discours indirect libre, la subjective libre indirecte constituent le point de contact entre le parcours poétique et dans le même temps théorique de l'auteur. La régression dans la parole de l’autre, ou, comme au cinéma, dans le regard de l’autre, représente en dernière instance la tentative de l’auteur de traduire sur le plan littéraire et cinématographique la réalité de conflits historiques et existentiels. / This doctoral thesis studies the free indirect style in Pasolini's works through a double path of research. On one hand it takes into account his literary and cinematic production; on the other it studies the linguistic and semiotic principles on which its free indirect style hinges. This double path has been crossed in the light of four notions that Pasolini developed in his theoretical essays along his artisticactivity. The first one is the “regression”, elaborated in the 40s in order to describe the usage of the Friulian dialect of his early poems. The second one is the “sentimental connection”, which Pasolini discovered in Gramsci's Prison Notebooks and he employed to analyse the relationship between intellectuals and subaltern classes. The third one concerns the free indirect discourse used in Pasolini's Roman novels of the 50s and studied from a linguistic and semiotic point of view in some essays. The last one is the free indirect subjective theorised in the 60s to describe the cinematic adaptation of the free indirect style.Regression, sentimental connection, free indirect discourse and free indirect subjective are the most important notions of Pasolini's free indirect style. They show how the author established itslinguistic, political and sentimental relationship with the subalterns that populates his literary works aswell as his movies.
179

MODELOS BIOMÉTRICOS APLICADOS AO MELHORAMENTO GENÉTICO DE TRIGO DUPLO PROPÓSITO / BIOMETRIC MODELS APPLIED TO BREEDING OF DUAL PURPOSE WHEAT

Carvalho, Ivan Ricardo 09 March 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The dual purpose wheat has the capacity to produce forage and grain, through the expression of morphological and bromatologic traits and yield components. Thus, the overall goal was to identify biometric models to understand the interrelationships between traits, direct and indirect selection in breeding wheat for dual purposes. The specific objectives of this study were to determine the canonical correlations between groups of morphological traits and grain yield, and identify the direction and the magnitude of the relationship; and identify the phenotypic relationships of cause and effect bromatologic between forage characters in wheat genotypes under different dual purpose cutting managements. The experiments were conducted in the growing seasons 2013 and 2014 in the experimental area of the Federal University of Santa Maria Campus Frederico Westphalen - RS. A randomized complete block design was used in three trials, the first experiment was arranged in a factorial: five genotypes (BRS Tarumã, BRS Umbu, BRS Figueira, BRS Guatambu and BRS 277) x four cutting managements (uncut, a cut, two cuts and three cuts). The second experiment was arranged in a factorial: Five genotypes (BRS Tarumã, BRS Umbu, BRS Figueira, BRS Guatambu and BRS 277) x Three cutting managements (first cut, second cut and third cut). The traits evaluated were: number of tillers per plant (AF), stem diameter of tillers (DAF), diameter of the main stem (DCP), number of fertile tillers (AFF), number of ears per square meter (ESPM), number of grains per ear (NGE), grain weight per ear (MGE), thousand grain weight (MMG), grain yield (RG), weight hectolitre (PH), green matter per hectare (MV), dry matter per hectare (MS), percentage of hemicellulose (HEM), cellulose (CEL), mineral matter (MM), neutral detergent fiber (FDN), acid detergent fiber (FDA), lignin (LIG), total carbohydrates (CT), carbohydrates no fiber carbohydrates (CNF), crude protein (PTN), and lipids (LIP). Groups of morphological traits and grain yield in wheat dual purpose reveal highly significant relationships. In the management at uncut and one cut wheat, associations are similarly established for both groups, by increasing the DCP, and determining the ESPM the increase, NGE and MGE, MMG, PH and RG. With two cuts the associations are established through the DAF, which influences an increase in MMG, PH and RG. Three cuts showed that the increase in AF increment the ESPM, NGE and MGE, MMG, PH and RG. The indirect selection aimed at increasing the PTN in the first cut can be based on CT, CNF and MV. The second cut provides indirect selection with LIG, CNF, MV and MS. The increase of PTN in the third cut can be obtained by indirect selection to the FDA, CEL, LIG, MM, MV and MS. Indirect selection through forage characters and bromatologic can be successful, since it considers the effect assigned to each cutting management. / O trigo duplo propósito apresenta capacidade de produzir forragem e grãos, através da expressão de caracteres morfológicos, bromatológicos e componentes do rendimento. Desta maneira, o objetivo geral foi identificar modelos biométricos que permitam compreender as inter-relações entre caracteres, e direcionar a seleção indireta no melhoramento genético de trigo duplo propósito. Os objetivos específicos deste trabalho foram: determinar as correlações canônicas entre grupos de caracteres morfológicos e do rendimento de grãos, e identificar o sentido e a magnitude das relações; e identificar as associações fenotípicas de causa e efeito entre caracteres forrageiros e bromatológicos em genótipos de trigo duplo propósito submetidos a diferentes manejos de corte.Os experimentos foram realizados nas safras agrícolas 2013 e 2014 na área experimental da Universidade Federal de Santa Maria Campus de Frederico Westphalen RS. Utilizou-se o delineamento de blocos ao acaso em três repetições, o primeiro experimento foi organizado em fatorial: Cinco genótipos (BRS Tarumã, BRS Umbu, BRS Figueira, BRS Guatambu e BRS 277) x Quatro manejos de corte (sem corte, um corte, dois cortes e três cortes). O segundo experimento foi organizado em fatorial: Cinco genótipos (BRS Tarumã, BRS Umbu, BRS Figueira, BRS Guatambu e BRS 277) x Três manejos de corte (primeiro corte, segundo corte e terceiro corte). Os caracteres avaliados foram: número de afilhos por planta (AF), diâmetro do colmo dos afilhos (DAF), diâmetro do colmo principal (DCP), número de afilhos férteis (AFF), número de espigas por metro quadrado (ESPM), número de grãos por espiga (NGE), massa de grãos por espiga (MGE), massa de mil grãos (MMG), rendimento de grãos (RG), peso hectolitro (PH), massa verde por hectare (MV), massa seca por hectare (MS), percentual de hemicelulose (HEM), celulose (CEL), material mineral (MM), fibras em detergente neutro (FDN), fibras em detergente ácido (FDA), lignina (LIG), carboidratos totais (CT), carboidratos não fibrosos (CNF), proteína bruta (PTN), e lipídios (LIP). Os grupos de caracteres morfológicos e de rendimento de grãos em trigo duplo propósito revelam relações altamente significativas. No manejo sem cortes e com um corte, associações são estabelecidas similarmente para ambos os grupos, através do aumento do DCP, sendo determinante ao acréscimo de ESPM, NGE e MGE, MMG, PH e RG. Com dois cortes as associações são estabelecidas através do DAF, que influencia o aumento da MMG, PH e RG. Com três cortes evidencia-se que o aumento do AF incrementam ESPM,NGE e MGE, MMG, PH e RG.A seleção indireta visando incrementar PTN no primeiro corte pode ser baseada nos CT,CNF e MV. O segundo corte proporciona a seleção indireta com a LIG, CNF, MV e MS. O incremento de PTN no terceiro corte poderá ser obtido através da seleção indireta com FDA, CEL, LIG, MM, MV e MS. A seleção indireta através dos caracteres forrageiros e bromatológicos pode ser realizada com sucesso, desde que se considere o efeito atribuído a cada manejo de corte.
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Contrôle en temps réel de la précision du suivi indirect de tumeurs mobiles en radiothérapie

Remy, Charlotte 08 1900 (has links)
Le but de la radiothérapie est d’irradier les cellules cancéreuses tout en préservant au maximum les tissus sains environnants. Or, dans le cas du cancer du poumon, la respiration du patient engendre des mouvements de la tumeur pendant le traitement. Une solution possible est de repositionner continuellement le faisceau d’irradiation sur la cible tumorale en mouvement. L’e cacité et la sûreté de cette approche reposent sur la localisation précise en temps réel de la tumeur. Le suivi indirect consiste à inférer la position de la cible tumorale à partir de l’observation d’un signal substitut, visible en continu sans nécessiter de rayonnement ionisant. Un modèle de corrélation spatial doit donc être établi. Par ailleurs, pour compenser la latence du système, l’algorithme de suivi doit pouvoir également anticiper la position future de la cible. Parce que la respiration du patient varie dans le temps, les modèles de prédiction et de corrélation peuvent devenir imprécis. La prédiction de la position de la tumeur devrait alors idéalement être complétée par l’estimation des incertitudes associées aux prédictions. Dans la pratique clinique actuelle, ces incertitudes de positionnement en temps réel ne sont pas explicitement prédites. Cette thèse de doctorat s’intéresse au contrôle en temps réel de la précision du suivi indirect de tumeurs mobiles en radiothérapie. Dans un premier temps, une méthode bayésienne pour le suivi indirect en radiothérapie est développée. Cette approche, basée sur le filtre de Kalman, permet de prédire non seulement la position future de la tumeur à partir d’un signal substitut, mais aussi les incertitudes associées. Ce travail o re une première preuve de concept, et montre également le potentiel du foie comme substitut interne, qui apparait plus robuste et fiable que les marqueurs externes communément utilisés dans la pratique clinique. Dans un deuxième temps, une adaptation de la méthode est proposée afin d’améliorer sa robustesse face aux changements de respiration. Cette innovation permet de prédire des régions de confiance adaptatives, capables de détecter les erreurs de prédiction élevées, en se basant exclusivement sur l’observation du signal substitut. Les résultats révèlent qu’à sensibilité élevée (90%), une spécificité d’environ 50% est obtenue. Un processus de validation innovant basé sur ces régions de confiance adaptatives est ensuite évalué et comparé au processus conventionnel qui consiste en des mesures de la cible à intervalles de temps fixes et prédéterminés. Une version adaptative de la méthode bayésienne est donc développée afin d’intégrer des mesures occasionnelles de la position de la cible. Les résultats confirment que les incertitudes prédites par la méthode bayésienne permettent de détecter les erreurs de prédictions élevées, et démontrent que le processus de validation basé sur ces incertitudes a le potentiel d’être plus e cace que les validations régulières. Ces approches bayésiennes sont validées sur des séquences respiratoires de volontaires, acquises par imagerie par résonance magnétique (IRM) dynamique et interpolées à haute fréquence. Afin de compléter l’évaluation de la méthode bayésienne pour le suivi indirect, une validation expérimentale préliminaire est conduite sur des données cliniques de patients atteints de cancer du poumon. Les travaux de ce projet doctoral promettent une amélioration du contrôle en temps réel de la précision des prédictions lors des traitements de radiothérapie. Finalement, puisque l’imagerie ultrasonore pourrait être employée pour visualiser les substituts internes, une étude préliminaire sur l’évaluation automatique de la qualité des images ultrasonores est présentée. Ces résultats pourront être utilisés ultérieurement pour le suivi indirect en radiothérapie en vue d’optimiser les acquisitions ultrasonores pendant les traitements et faciliter l’extraction automatique du mouvement du substitut. / The goal of radiotherapy is to irradiate cancer cells while maintaining a low dose of radiation to the surrounding healthy tissue. In the case of lung cancer, the patient’s breathing causes the tumor to move during treatment. One possible solution is to continuously reposition the irradiation beam on the moving target. The e ectiveness and safety of this approach rely on accurate real-time localization of the tumor. Indirect strategies derive the target positions from a correlation model with a surrogate signal, which is continuously monitored without the need for radiation-based imaging. In addition, to compensate for system latency, the tracking algorithm must also be able to anticipate the future position of the target. Because the patient’s breathing varies over time, prediction and correlation models can become inaccurate. Ideally, the prediction of the tumor location would also include an estimation of the uncertainty associated with the prediction. However, in current clinical practice, these real-time positioning uncertainties are not explicitly predicted. This doctoral thesis focuses on real-time control of the accuracy of indirect tracking of mobile tumors in radiotherapy. First, a Bayesian method is developed. This approach, based on Kalman filter theory, allows predicting both future target motion in real-time from a surrogate signal and associated uncertainty. This work o ers a first proof of concept, and also shows the potential of the liver as an internal substitute as it appears more robust and reliable than the external markers commonly used in clinical practice. Second, an adaptation of the method is proposed to improve its robustness against changes in breathing. This innovation enables the prediction of adaptive confidence regions that can be used to detect significant prediction errors, based exclusively on the observation of the surrogate signal. The results show that at high sensitivity (90%), a specificity of about 50% is obtained. A new validation process based on these adaptive confidence regions is then evaluated and compared to the conventional validation process (i.e., target measurements at fixed and predetermined time intervals). An adaptive version of the Bayesian method is therefore developed to valuably incorporate occasional measurements of the target position. The results confirm that the uncertainties predicted by the Bayesian method can detect high prediction errors, and demonstrate that the validation process based on these uncertainties has the potential to be more e cient and e ective than regular validations. For these studies, the proposed Bayesian methods are validated on respiratory sequences of volunteers, acquired by dynamic MRI and interpolated at high frequency. In order to complete the evaluation of the Bayesian method for indirect tracking, experimental validation is conducted on clinical data of patients with lung cancer. The work of this doctoral project promises to improve the real-time control of the accuracy of predictions during radiotherapy treatments. Finally, since ultrasound imaging could be used to visualize internal surrogates, a preliminary study on automatic ultrasound image quality assessment is presented. These results can later be used for indirect tracking in radiotherapy to optimize ultrasound acquisitions during treatments and facilitate the automatic estimation of surrogate motion.

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