This thesis is a biosystematic study focusing on the taxonomy and variability of selected taxa of the genus Sorbus, one of the most diverse and taxonomically complicated plant groups in Europe. Classical and modern biosystematic methods - comparative study, chromosome counting, analysis of nuclear microsatellite markers, flow cytometry, and traditional multivariate and outline morphometric analyses were used to assess the morphological, karyological and genetic variability of the genus. The final synthesis of these approaches led to the description of several new taxa (species, hybrids and a subgenus) and the correction of several taxonomic misinterpretations. To reveal ongoing evolutionary processes responsible for the generation of the observed variability, the reproductive modes of 42 Sorbus taxa were examined using flow-cytometric seed and pollen screens. Apart from revealing major trends, the study estimates the frequency of rare events and provides several novel conclusions that are relevant both specifically to Sorbus/Rosaceae and to apomixis in general.

No description available.

A construção civil é o maior consumidor de recursos naturais do planeta, apropriando-se atualmente de mais da metade da massa total dos materiais extraídos. Neste contexto, o desenvolvimento de sistemas construtivos que proporcionem uma redução do consumo de materiais, conhecida como o princípio da desmaterialização dos edifícios, pode ser uma estratégia para a redução do impacto que a construção civil exerce sobre o ambiente, e um passo em direção a uma economia mais sustentável. A utilização de placas cimentícias para a produção de vedações vem crescendo em várias partes do mundo, seja para a produção de vedações verticais externas, seja como revestimento não aderido sobre vedos existentes, destinados tanto a melhoria estética quanto o desempenho destas fachadas. Uma vedação com placas cimentícias possui em torno de 25% da massa de uma alvenaria tradicional constituída por blocos de concreto para a execução de uma mesma área de vedação vertical, o que pode contribuir ainda para uma redução dos materiais empregados nas estruturas e fundações de um edifício. Apesar da utilização destas placas cimentícias estar coerente com a estratégia da desmaterialização, algumas experiências de vedações executadas com estes componentes manifestaram problemas de manutenção de suas características ao longo do tempo, apresentando fissuras geralmente nas juntas entre placas. Verificando-se as propriedades dos materiais que constituem esta placa cimentícia, principalmente a variação dimensional em relação à temperatura e umidade, constatou-se uma incompatibilidade entre a amplitude das variações dimensionais resultantes e os sistemas de fixação e juntas empregados para a sustentação das mesmas. A avaliação experimental de choque térmico comprovou a influência destas variações para a deterioração das juntas entre as placas. Com base nesta constatação, e em análises dos processos de fixação de placas cimentícias adotados por fornecedores em diversas partes do mundo, foi desenvolvido neste trabalho um novo sistema de fixação para placas cimentícias e de juntas entre estas com capacidade de atender a esta variação dimensional. Realizaram-se protótipos destes componentes os quais foram submetidos a uma avaliação experimental de choque térmico, resultando em nenhuma alteração visível nas juntas e nas superfícies destas placas. Como resultado concluiu-se que a criação de mecanismos que possibilitem acomodação às variações dimensionais, tanto nos dispositivos de fixação destas à estrutura, quanto nos acabamentos das juntas, podem contribuir significativamente para a durabilidade do sistema de vedações constituída por placas cimentícias. / The construction industry is the largest consumer of natural resources in the planet, currently appropriating more than half of mass of the total material extracted. In this context, the development of building systems that provide their dematerialization can be considered as a strategy to reduce the environmental construction impact, and a step toward a more sustainable economy. The use of fiber cement boards for the building production is growing in many parts of the world, to produce external vertical building enclosure or building envelopes, to improving the aesthetics and performance of these facades. A fiber cement board walls weigh around 25% of the traditional masonry mass made of concrete blocks for the same area of vertical building enclosure which can further contribute to a reduction of the materials used in building structures and foundations. Although the use of fiber cement boards complies with the dematerialization strategy, some experiments carried out with these cladding showed maintenance problems over time, usually cracks in the joints between panels. Checking the properties of materials constituting fiber cement boards, especially the dimensional variation due to changing temperature and humidity, there was an incompatibility between these dimensional variations amplitude and fixing systems and joints used to support them. The thermal shock experimental evaluation proved the influence of these variations on joints deterioration. Based on this observation, and on analyzes of the fiber cement suppliers recommendations over the world, a new system for fixing fiber cement board and joints between them was developed in this work with capacity to adapt to this dimensional variation. Prototypes of these components were made and submitted the thermal shock evaluation, resulting in no visible changes in the joints and on the surfaces of these panels. As a result, it was concluded that the creation of mechanisms that allow accommodating the dimensional variations, both in fixing these panels to the structure, and in the joints finishing can significantly contribute to the vertical building enclosure system durability.

O design de interação é uma disciplina de design relativamente nova que pode ser compreendida como o design dos aspectos subjetivos e qualitativos de tudo o que é digital e também interativo. Já o esboço é uma prática muito comum nas disciplinas de design e consiste em um tipo de desenho feito à mão no papel para testar alternativas e comunicá-las para outros profissionais. O design de interação traz novos desafios para a prática de esboços, pois além das telas é necessário representar as ações do usuário e as modificações do sistema ao longo do tempo. Um levantamento da situação atual mostra que as técnicas que existem apresentam limitações importantes e que o assunto ainda é pouco explorado. Portanto o objetivo deste trabalho foi procurar aprimorar os esboços no design de interação, com quatro linhas de ação: analisar as especificidades da prática de esboços no design de interação para compreender as oportunidades de melhoria; desenvolver uma técnica, a ActionSketch, para buscar aproveitar estas oportunidades; verificar se a ActionSketch auxilia no processo de fazer esboços no design de interação; analisar o uso da técnica para procurar compreender como auxilia ou não o processo. Para atingir estes objetivos, adotamos o plano de ação descrito a seguir. Realizamos uma extensa revisão da literatura. Desenvolvemos propostas de técnicas e as refinamos através de iterações de exercícios e de entrevistas com profissionais. Apresentamos a ActionSketch em oficinas para grupos de profissionais da área, onde coletamos resultados do uso da técnica para em seguida analisá-los. A versão da técnica utilizada neste trabalho (v0.8) é composta por quatro partes: quadros, cores, símbolos e regras. Os quadros são uma forma para lidar com a questão temporal, as cores buscam separar as ações do usuário e do sistema, os símbolos são notações para deixar o desenho mais ágil e as regras são boas práticas para orientar o uso da técnica. Esta versão foi apresentada para 24 profissionais em quatro oficinas, seguidas de um período de uso continuado de 18 dias em média e fechado com entrevistas individuais para coletar comentários. Para atingir nosso objetivos a análise dos dados foi feita em dois níveis: um nível mais pragmático, para avaliar a adequação da técnica na sua aplicação prática, e um outro nível mais conceitual, onde pudemos investigar os aspectos mais gerais da prática de esboços, com foco no design de interação. De maneira sucinta os resultados obtidos indicam que a ActionSketch: auxilia o processo cognitivo; facilita a comunicação quando ao menos um designer conhece a técnica; pode ser modificada ou aplicada parcialmente; tem um aprendizado inicial rápido, que pode evoluir de maneira modular; é particularmente adequada para detalhes da interação. Em termos práticos a técnica se mostrou suficientemente adequada para uso e apontou possíveis melhorias. Já no aspecto teórico pudemos verificar a importância da representação da interação nos esboços, que trouxe diversos benefícios para o processo. O trabalho também aponta algumas direções futuras, como uma nova versão da ActionSketch e sua divulgação online de maneira modular e colaborativa. / Interaction design is a relatively new discipline which can be understood as the design of the subjective and qualitative aspects of everything that is both digital and interactive. Sketching is a common practice in design and consists of freehand drawings made on paper to test alternatives and communicate them to other professionals. Interaction design brings new challenges to the practice of sketches, because of the need to represent the interaction as well as the visual layout of the interface. A survey of current practices shows significant limitations and that the subject is still little explored. Therefore the aim of this work was to improve sketching in interaction design, with four lines of action: to analyze the specifics of practice in interaction design sketches to understand the opportunities for improvement; to develop a technique, called ActionSketch, to try to take advantage of these opportunities; to verify if ActionSketch improves the process of sketching in interaction design; to analyze the use of the technique to try to identify how it helps or hinders the process. To achieve these objectives, we adopted the following plan of action. We conducted an extensive literature review. We developed proposals of the technique and refined them through iterations of exercises and interviews with professionals. We then presented ActionSketch in workshops for groups of professionals, from where we collected the results. The version of the technique used in this work (v0.8) consists of four parts: frames, colors, symbols and rules. Frames are a way to deal with the question of representing time, the colors try to evidence the user and system actions, symbols are notations to improve the speed of drawing and rules are good practices that guide the use of the technique. This version was presented to 24 professionals in four workshops, followed by a period of continuous use of 18 days on average and closed with individual interviews to gather feedback. To achieve our objective data analysis was done on two levels: a more pragmatic level, to assess the adequacy of the technique in practical application, and another more conceptual level, where we investigate the more general aspects of the practice of sketches, with focus on interaction design. Briefly the results obtained indicate that ActionSketch: assists the cognitive process; facilitates communication when at least one designer knows the technique; may be modified or partially applied; has a smooth learning curve, which can evolve in a modular way; is particularly adequate for details of the interaction. In practical terms the technique seemed adequate enough for use and indicated some points for improvement. In the theoretical aspect we could verify the importance of representing the interaction in sketches, which brought many benefits to the process. The study also points to some interesting future directions, such as a new version of ActionSketch and the creation of a collaborative site for it\'s publication.

Dans cette thèse, des structures MEMS de type micropoutre ont été conçues pour des applications capteurs. Un procédé de fabrication alternatif au silicium, associant la technique de sérigraphie à l'utilisation d’une couche sacrificielle (SrCO3), a été utilisé pour la réalisation de micropoutres piezoélectriques (PZT, matériau servant à la fois d’actionneur et de transducteur) dans un premier temps. Des tests de détection en phase gazeuse ont été réalisés avec et sans couche sensible avec succès à l’aide du mode de vibration non conventionnel 31-longitudinal. Le toluène a notamment pu être détecté à des concentrations voisines de 20ppm avec une couche sensible PEUT. D’autres espèces telles que l’eau, l’éthanol ou l’hydrogène ont été détectés sans couches sensibles afin de s’affranchir des contraintes liées à celle-ci (vieillissement notamment). Des tests préliminaires de caractérisation en milieu liquide ont également été réalisés avec dans l’optique la détection d’espèces en phase liquide. Par ailleurs, un capteur de force a été conçu et réalisé avec le même procédé de fabrication. Ce dernier est composé d’une micropoutre en matériau diélectrique sur laquelle est intégrée une piezorésistance servant à la transduction du signal associé à la déformation subie par la micropoutre. Des détections de force en mode statique (sans actionneurs) ont permis de caractériser les capteurs, notamment en termes de sensibilité, de gamme de force et de force minimale détectable ou encore de linéarité. / The project concerns the conception, fabrication and characterization of cantilever-type MEMS structures for sensors applications. An alternative process to silicon related ones, associating the screen-printing technique to a sacrificial layer (SrCO3), was used to realize piezoelectric cantilevers (PZT material utilized as actuator and transducer) in a first time. Detections in gas phase were performed successfully with and without sensitive layer thanks to the unusual 31-longitudinal vibration mode. Namely, we were able to detect toluene at concentrations as low as 20ppm with a PEUT sensitive layer. Other species like water, ethanol or hydrogen could be detected without sensitive layer in order to get rid of the sensitive layer-related issues (ageing for example). Preliminary characterizations were carried out in liquid phase in a view to perform liquid phase detection. Besides, a cantilever-based force sensor, fabricated thanks to the same fabrication process was designed. This last one integrates a piezoresistor allowing the transduction of the mechanical signal linked to the strain overcome by the microcantilever. Force detections in static mode (without any actuator) permitted the sensors’ characterization. Indeed, their sensitivity, force range, minimal detectable force and linearity were carried out.

Cette recherche menée au sein du pôle de recherche et développement de la société Perfect Memory s'intéresse à l'accompagnement de la mémoire familiale via un dispositif technique, interrogé par le prisme des sciences de l'information et de la communication. Elle propose la construction d'une approche d'éditorialisation du document numérique permettant à chacun de s'approprier son patrimoine culturel au travers de l'utilisation du dispositif technique co-construit, l'application Web Famille TM. L'interrogation du milieu socio-économique de la préservation et la valorisation du patrimoine culturel du particulier, auquel Perfect Memory appartient, nous amène à nous interroger sur les enjeux d'un rapprochement entre les notions de « numérique » et de « mémoire ». Un cadre théorique est ainsi construit, le document numérique est appréhendé comme support d'un exercice de la mémoire, permis par la médiation du dispositif technique. L'éditorialisation, en tant qu'ensemble d'opérations réalisées sur le document numérique par l'intermédiaire du dispositif technique, est placée au cœur de notre problématique axée sur les modalités d'accompagnement des pratiques mémorielles via le service Famille TM. La construction de notre approche d'éditorialisation est séparée en deux moments. Dans un premier temps, un corpus de documents numériques - productions familiales préservées par différentes institutions patrimoniales - est interrogé par une méthodologie sémiotique afin d'extraire les éléments saillants invariants à leur interprétation, que nous rassemblons sous l'appellation de marqueurs de mémoire. Dans un second temps, les catégories de marqueurs construits sont transcrites en recommandations éditoriales et ergonomiques destinées au dispositif technique Famille TM. Articulé jusqu'ici autour d'un axe unique - la documentarisation de l'archive -, le dispositif est enrichi de deux nouveaux modes - cinématographique et privé -, constituant autant de points d'entrée supplémentaires dans le document versé par l'utilisateur sur le service. L'approche d'éditorialisation du document est ainsi décomposée en trois modes, comportant chacun différents scénarii, articulation de fonctionnalités et d'une expérience utilisateur spécifiques, construits pour le service Famille TM. / This research project was made at the R&D department at Perfect Memory and focus on how to support family memory via a technological artifact. We question the artifact through the prism of information and communication sciences. The project offers to build a new approach, that of the editorialization of digital documents, enabling each user to rediscover their cultural heritage. This can be done by means of Famille TM, a co-built Web app. Following a study of the cultural heritage market as applied to private individuals, to whom Perfect Memory belongs, we proceed to a cross analysis of two concepts : "Digital" and "Memory". Starting from these, we built a theoretical framework in which we consider digital documents as a base for memory training. The technological artifact allows such training through a mediation process. Editorialization, as a set of processes made on the digital document through a technological artifact, appears as central to our concern: to design ways to support memory habits through Famille TM. We divide the construction of an editorialization approach into two steps. First, we build a corpus of digital documents - home movies - from various cultural heritage organizations. Then we interrogate the corpus through a semiotic methodology in order to gather salient and invariant elements in each interpretation. We name them memory markers. In a second step, we transcribe the markers categorization into editorial and ergonomic recommendations for Famille TM. Until today, the technological artifact consisted in one single mode: the documentation of archives. We introduce two extra modes: the cinematographic experience and the private experience. Each mode provides the user with an original entry point into documents uploaded on the app. To summarize our editorialization approach, we implement three modes into Famille TM and for each of them we design several scenarios made up of specific features and user experiences.

Les techniques de criblage actuelles (in vitro et in silico) sont dépendantes des efforts menés en biologie médicinale pour identifier des cibles biologiques pertinentes ; cibles difficiles à définir pour les maladies génétiques dites "perte de fonction". De plus, les composés issus de ces cribles s'avèrent souvent inefficaces et/ou toxiques une fois confrontés à la complexité physiologique d'un organisme entier. Pour contourner ce problème, nous proposons d'utiliser le nématode C. elegans, notamment pour des maladies répondant aux critères suivants : i) physiopathologie complexe et/ou mal comprise excluant le développement à court terme de médicaments sur une base rationnelle, ii) peu d’espoir de thérapie génique/cellulaire à court terme, iii) conservation chez C. elegans du gène relié à la maladie humaine et induisant un phénotype exploitable une fois inactivé. Nous démontrons ici que ce petit nématode permet de tester, à moindre coût, un grand nombre de composés chimiques tout en conservant la complexité physiologique d'un animal entier. De plus, la souplesse génétique de cet animal permet d'apporter rapidement des informations sur le mode d'action des composés identifiés. Ainsi, en plus du but initial visant à identifier des molécules bioactives à intérêt thérapeutique, cette approche peut permettre de dégager de nouvelles cibles moléculaires utiles pour l'industrie chimique, et cruciales pour la recherche de traitements contre les maladies perte de fonction. Finalement, nous présentons comment mettre en place une telle stratégie, notamment pour la myopathie de Duchenne, l'amyotrophie spinale et le syndrome de Schwartz-Jampel. Enfin, nous présentons les résultats obtenus lors des différentes campagnes de criblage, les validations des molécules les plus prometteuses et les travaux effectués pour tenter de comprendre leur mode d'action chez le nématode. / Current high-throughput screening methods for drug discovery rely on the existence of targets. Moreover, most of the hits generated during screenings turn out to be invalid after further testing in animal models. To by-pass these limitations, efforts are now being made to screen chemical libraries on whole animals. One of the most commonly used animal model in biology is the murine model Mus musculus. However, its cost limits its use in large-scale therapeutic screening. In contrast, the nematode Caenorhabditis elegans is gaining momentum as screening chemical tool. This tiny worm combines genetic amenability, low cost, and culture conditions that are compatible with large-scale screens. Its main advantage is to allow high-throughput screening in a whole-animal context. Moreover, its use is not dependent on the prior identification of a target and permits the selection of compounds with an improved safety profile. Here, we introduce this approach with the Duchenne Muscular Dystrophy, the Spinal Muscular Dystrophy and the Schwartz-Jampel syndrome. We present the methodology used with each model to screen up to 7,000 compounds and the results of these screening campaigns. We further present the validation of our best hits and try to understand their mechanism of action.

Les fichiers accompagnant le document sont en format Microsoft Excel 2010. / Les modèles classiques de signalisation cellulaire eucaryotes sont généralement organisés en voies linéaires et hiérarchiques, impliquant un ensemble de facteurs restreint. Ces facteurs forment un circuit isolé qui transmet une information externe vers sa destination, d’où une réponse cellulaire sera alors engendrée. Or, ces modèles sont justement le fruit d’approches expérimentales réductionnistes qui ne permettent pas d’intégrer aisément la contribution de facteurs multiples, ni de faire une évaluation quantitative de l’apport des composantes du système. Le développement de techniques d’investigation plus holistiques, telles la génomique fonctionnelle et la protéomique, permettent d’examiner de manière systématique et quantitative l’apport d’ensembles larges de facteurs et de les mettre en relation avec d’autres systèmes cellulaires. Il y aurait donc lieu de réévaluer le modèle de voie de signalisation linéaire au profit d’un modèle de réseau de signalisation multiparamétrique, comportant plusieurs branches d’entrée et sortie de signal interagissant avec d’autres systèmes cellulaires. Cet ouvrage porte sur la voie RAS/MAPK, l’un des principaux axes de signalisation associé à la prolifération et la différenciation cellulaires. Le sujet y est d’abord abordé sous l’angle d’une perspective historique, en mettant l’emphase sur les contributions des études de génétique classique chez les organismes modèles D. melanogaster et C. elegans. Il fait ensuite état du développement du criblage par ARNi pan-génomique dans ces deux modèles en le comparant aux approches de criblage génétique classique. Le corps de l’ouvrage décrit ensuite les résultats expérimentaux d’une campagne de criblage par ARNi visant à dresser une carte globale des régulateurs de la voie chez la drosophile. Trois groupes de régulateurs identifiés dans ce crible ont été caractérisés de manière plus détaillée. Dans un premier article, nous démontrons que les composantes du complexe EJC ont un impact sur l’épissage de mapk; une découverte doublement intéressante puisque l’EJC était jusqu’alors associé qu’à la régulation post-épissage des ARNm. Une seconde publication fait état de l’ensemble des résultats du crible ARNi, mettant l’emphase sur un ensemble de facteurs d’épissage qui modulent également mapk. Nous y montrons que l’impact de ces facteurs sur l’épissage alternatif est différent de celui de l’EJC, suggérant ainsi deux modes de régulation distincts. Finalement, dans un troisième manuscrit, nous nous attardons au rôle d’Usp47, une déubiquitinase qui, contrairement aux autres facteurs identifiés dans le crible, régule l’expression de MAPK de manière post-traductionnelle. Nous y détaillons une stratégie de criblage d’interaction génétique par ARNi visant à identifier des facteurs reliés fonctionnellement à Usp47. Ce second crible a permis l’identification de trois facteurs reliés au « N-end rule », un mécanisme de dégradation des protéines caractérisé par la reconnaissance des résidus N-terminaux de protéines ou peptides. Il existait jusqu’alors très peu de données quant à la régulation de l’expression des composantes de la voie MAPK, ce qui rend la description d’un large réseau de régulateurs agissant sur l’expression de MAPK d’autant plus insoupçonnée. L’absence d’un réseau équivalent rattaché aux autres composantes de la voie laisse supposer que MAPK serait un noeud servant de point d’entrée à ce type de régulation dans le système RAS/MAPK. De plus, nos travaux témoignent de la capacité de la génomique fonctionnelle à mettre en relation différents systèmes cellulaires de manière plus globale et à quantifier les liens établis entre eux. / The classical model of eukaryotic cellular signalling generally involves hierarchically organized linear pathways involving a restricted set of elements. These generally function together as an insulated circuit, transmitting information from the outside to the intracellular compartment involved in eliciting a response. These models, often the fruit of reductionist experimental approaches, do not allow for the integration of multiple inputs nor for a gradation of responses. The recent emergence of more holistic investigation techniques has brought about the re-evaluation of these classical models in favor of multiparametric signalling networks. This thesis focuses on the RAS/MAPK pathway, one of the cell’s main proliferation and differentiation signalling conduits, beginning with a historical perspective covering the contributions of model organism genetics to the current pathway model. This provides context for the description of a whole-genome RNAi screen experiment that we carried out to obtain a global view of regulators in Drosophila. Three groups of factors emerging from this screen were then examined in more detail. A first article shows that the exon junction complex (EJC) plays a role in mapk alternative splicing, an observation that is unexpected given that this complex was not previously known to act on splicing. A second paper details the genome wide screening campaign and focuses on a large set of splicing factors that also regulate mapk, albeit in a distinct manner than the EJC’s. Finally, a manuscript in a third segment examines Usp47 function and finds it to control MAPK levels post-translationally. An RNAi-based genetic interaction screen is then used to identify factors functionally related to Usp47 capable of counteracting its impact on MAPK levels. Three such factors identified through this technique are linked to the N-end rule protein degradation pathway. Regulation of core pathway component expression is a poorly described process, which makes the identification of a large set of factors regulating MAPK expression all the more unusual. Moreover, the absence of such regulation linked to other pathway components suggests that MAPK may act as a node incorporating inputs of this type into RAS/MAPK signaling dynamics.

Cette thèse, relevant de la problématique des avatars et des métaphores de la figure humaine et deses multiples représentations scéniques, interroge les créations contemporaines de la marionnette. Elle a pourpoint de départ la pratique de la marionnette et la place conférée à la figure dans les dispositifs scéniques.Fondés sur des confluences des figures animées et des images de synthèse, les dispositifs contemporains issusdes nouvelles techniques de l’image et du son ont permis de dépasser la structure traditionnelle de lamarionnette. A mi-chemin entre poupée et forme raffinée, la marionnette dépasse ses contours et ouvre vers denouvelles représentations scéniques : des ombres, des doubles virtuels, des avatars de synthèse, pouvant êtretransformés et évolués en temps réel. Toutes ses représentations posent la question de l’incarnation. Ainsi lafigure de l’avatar se présente comme un possible prolongement de la marionnette. Les outils technologiquespermettent une nouvelle manière de former, d’élaborer la figure. Ils offrent une infinie possibilité de ladédoubler, de la multiplier, de la répliquer. Dans ce geste répétitif la figure tend progressivement vers uneffacement de ses contours. Loin de la forme anthropomorphique, elle symbolise le plus souvent une idée, unconcept, un mot en jouant sur l’essence de la matière et les agencements plastiques d’objets et de matières.Quant aux possibles dédoublements de l’interprète réalisés grâce aux technologies de l’image et du son, lecorps vivant en chair et en os se démultiplie dans des figurations comme les ombres, les reflets et les doublesvirtuels. Ces derniers deviennent un indice, une icône de notre présence. La démultiplication spatiale etcorporelle de leur présence iconique fait scintiller les nombreux subterfuges d’une ruse scénique. Car cettenouvelle figure, construite par les jeux d’illusions et de leurres qu’autorise l’usage du numérique effaceprogressivement les contours traditionnels de la figure humaine en brouillant les pistes d’une identificationtangible. Ces nouvelles figures se présentent comme des images décalées et sont une véritable invitation àpenser l’absence et la présence, l’apparition et la disparition. La figure s’ouvre à une interprétation multiple etoffre une vision différée en interrogeant la place de l’humain dans notre société. Les dispositifs scéniques quiabritent ces figures deviennent une véritable iconostase pour leur déploiement. Espace d’une fiction du regard,la figure compose et décompose sans cesse ses contours en offrant son image à celui qui la regarde. Lespectateur est invité à vivre une expérience oculaire en le transformant en véritable acte de voir. / This thesis studies the problematics of avatars and metaphors of the human form and its manifoldstage representations; it questions contemporary ‘creation’ in the field of puppetry. The practice of puppetryand the place bestowed on the human form in staging devices are the starting point of the study. Located at theconvergence of animated figures and of computer graphics, contemporary staging devices that stem from newtechniques of sound and video have allowed us to surpass the traditional framework of the puppet. Halfwaybetween doll and refined figure, the puppet goes beyond its outline and opens the path towards new stagerepresentations; shadows and virtual doubles, CGI avatars, which can all be transformed and developed in realtime. All its representations beg the question of incarnation. Thus the face of the avatar is presented as apossible extension of the puppet. Technological tools allow new ways of devising and developing the face. Theyoffer infinite possibilities to divide the face, to multiply and replicate it. In this repetitive gesture, the facetends gradually to be effaced of its outlines. Far from the anthropomorphic figure, it symbolises here an ideamost often, a concept, a word that underscores the essence of the material and the visual arrangement of objectsand matter. As for the potential splitting of the performer achieved thanks to new technology in video andsound, the living boy in flesh and blood multiples as shadows, reflections and virtual doubles. The latterbecome a sign, an icon of our presence. Spatial and corporeal duplication of their iconic presence makes thenumerous subterfuges involved in a staging device sparkle. Because this new figure, built from simulatedreality games and digital lures, gradually erases the traditional contours of the human form by blurring thepaths to any tangible identification. These new forms are presented as staggered images and are a realinvitation to rethinking absence and presence, appearance and disappearance. The face/form is exposed tomultiple interpretations and offers a deferred vision by questioning the place of the human being in our society. Staging devices that shelter these forms become a true iconostasis for their demonstration. The face –the space belonging to the fiction of the gaze – incessantly makes and breaks its outlines by throwing up itsimage to those who watch him. The viewer is invited to undergo an ocular experience by transforming it into atrue act of seeing.

No description available.