In vivo imaging of the tonoplast intrinsic protein family in Arabidopsis roots

Background: Tonoplast intrinsic proteins (TIPs) are widely used as markers for vacuolar compartments in higher plants. Ten TIP isoforms are encoded by the Arabidopsis genome. For several isoforms, the tissue and cell specific pattern of expression are not known. Results: We generated fluorescent protein fusions to the genomic sequences of all members of the Arabidopsis TIP family whose expression is predicted to occur in root tissues (TIP1;1 and 1;2; TIP2;1, 2;2 and 2;3; TIP4;1) and expressed these fusions, both individually and in selected pairwise combinations, in transgenic Arabidopsis. Analysis by confocal microscopy revealed that TIP distribution varied between different cell layers within the root axis, with extensive co-expression of some TIPs and more restricted expression patterns for other isoforms. TIP isoforms whose expression overlapped appeared to localise to the tonoplast of the central vacuole, vacuolar bulbs and smaller, uncharacterised structures. Conclusion: We have produced a comprehensive atlas of TIP expression in Arabidopsis roots, which reveals novel expression patterns for not previously studied TIPs

Jeux vidéos (Les)

Rapport d\u27information fait au nom de la commission des affaires économiques et de la commission de la culture, de l\u27éducation et de la communication par le groupe de travail sur les jeux vidéo

Demise of Carnian platforms: large scale geometries and mechanisms of precipitation

During the Late Triassic, a climate change known as the Carnian Pluvial Event (CPE) resulted in a major crisis for carbonate producers. In the western Tethys, the change in carbonate production led to a dramatic modification of depositional geometries. The steep clinoforms of the high relief pre-crisis carbonate platforms were replaced by low angle ramp geometries. A quantitative three dimensional modeling of the geometry of sedimentary bodies in the Cortina d'Ampezzo area (North-eastern Italy) formed before, during and after the Carnian crisis, coupled with facies analysis, was performed in order to investigate in detail how the changes in shallow water carbonate precipitation influenced the depositional geometries of carbonate platforms. Facies and depositional geometries suggest that after the demise of high-relief, microbial dominated carbonate platforms, a phase of intermediate sedimentation took place, in which microbial carbonate mounds and loose carbonate and terrigenous sediments coexisted. The subsequent evolution to a ramp is characterized by the onset of a tide-dominated environment. In the study area, the sedimentary succession developed in a marine strait connecting two small basins. Both ebb and flood paleocurrents are documented and their directions are in agreement with the strait orientation, as inferred from the paleogeographic position of relict high-relief carbonate platforms. Facies and sedimentary structures related to variations in the hydraulic regime have been observed, including planar cross stratification, herringbone cross stratification, flaser to wavy to lenticular bedding and cyclical alternations of mainly oolitic-siliciclastic vs. mainly bioclastic-muddy laminae. The peculiarity of this tidal system is that, differently from all other known cases, it did not develop in a tectonically confined submarine graben or canyon, but in a marine passage between relict high-relief carbonate platforms. Sedimentary facies analysis, coupled with geological three dimensional modeling, led also to constrain the sequence stratigraphy of this complex stratigraphic interval, in which the eustatic and climatic signals can be disentangled. The climate change predates the sea-level drop and caused the demise of the microbial-dominated high-relief carbonate platforms. A surface similar to a drowning unconformity was thus generated, even though a transgression was not taking place. Only small isolated microbial carbonate mounds survived the crisis of high-relief platforms. The complete disappearance of microbial carbonates (i.e. mounds) and the definitive switch of the shallow water carbonates to loose-sediment dominated ramps coincides with a subsequent sea-level drop. Thus the demise of the Upper Triassic microbial dominated high-relief platforms of the Dolomites can be interpreted as a two step process: at first a climatic event killed the km-scale high-relief platforms; later a drop in sea level led to the definitive disappearance of the microbial carbonates

L'acte canularesque médiatique : dispositifs, procédés et enjeux communicationnels (Europe et Amérique du Nord, 2004-2008)

This thesis deals with the issue of a decade-long rise in the number of particular phenomena of mystification that use very elaborate communication mechanisms : the media hoaxes. Appeared in the 18th century and closely linked to ancient and popular practices, the elaborate hoax, associate with media and new technologies, implements audacious processes that became increasingly sophisticated. The analysis of nine hoaxes cases that have benefited from a wide media echoe during the period 2004 to 2008 emphasizes the significance of interaction between the author, his target and the audience. It also testifies the context's high impact upon the success of the action. The profound transformations that go through worldwide societies and the upheavals that modify and often weaken the information world obviously represent a favourable ground for a multiplication of media hoaxes. From the erosion of conditions in journalism practices, the fiercecompetition which affects various media, the growing attraction for fictions as true, to the constant search for novelty and the spectacular, false information and other mischievous mystifications find every reason to proliferate.As the transgressive course taken by media hoaxes in recent years has led to a stringent legislation and the victims' retaliations, we question the uncertain future of this research topic as a practice in the final part of the thesis.Cette thèse porte sur la recrudescence notable depuis une décennie de certains phénomènes singuliers de mystification mettant en jeu des dispositifs communicationnels assez élaborés, connus sous l’appellation de canulars médiatiques. Apparu au XVIIIe siècle et en filiation étroite avec certaines pratiques populaires plus anciennes, l’acte canularesque associé à l’usage des médias engage la mise en œuvre de procédés audacieux qui, au fil du temps et de l’émergence de nouveaux moyens de communication, n’ont cessé de se sophistiquer.L'analyse d'un corpus de neuf canulars ayant recueilli d'un fort retentissement médiatique au cours de la période 2004-2008 souligne l’importance du jeu des interactions qui s’établissent entre l’auteur, sa cible et le public exposé.Elle témoigne également de la forte incidence du contexte sur la réussite de l’acte. Les transformations profondes qui traversent actuellement la société à l’échelle internationale, ainsi que les importants bouleversements qui modifient et parfois fragilisent le monde de l’information, représentent à l’évidence un terrain propice à la multiplication des canulars médiatiques. Entre la précarisation des conditions d’exercice du journalisme, la concurrence effrénée qui affecte les médias, l’attrait grandissant pour les fictions se donnant pour vraies et la recherche permanente de l’inédit et du spectaculaire, les fausses nouvelles et autres mystifications malicieuses trouvent toute raison de proliférer.La tournure très transgressive prise par les canulars médiatiques au cours de ces dernières années a conduit récemment à la mise en place de législations plus coercitives et entraîné de la part de leurs victimes des mesures de rétorsion qui nous amènent, en dernière partie de cette thèse, à nous interroger sur le devenir incertain de l’objet et de sa pratique

O ensino de vocabulario em lingua estrangeira : uma proposta para sua sistematização

Orientador: Linda Gentry El-DashDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Estudos da LinguagemResumo: O objetivo deste estudo é investigar a aquisição de vocabulário em inglês como língua estrangeira entre alunos que estão no início do processo de aprendizagem dessa língua nas salas de aula de escolas públicas, ou seja, entre alunos freqüentando a quinta série do Ensino Fundamental. Essa necessidade surgiu do fato de os alunos, após quatro anos de contato com a língua inglesa, não possuírem um vocabulário limiar na língua-alvo que lhes possibilite realizar, com sucesso, as tarefas de compreensão em leitura propostas a partir da primeira série do Ensino Médio. Para investigar essa questão, atuamos como professora-pesquisadora, em uma escola da rede pública de ensino, durante o período de um ano letivo, utilizando-nos da técnica Total Physical Response (TPR) para o ensino do léxico em LE. Com o propósito de coletarmos dados de produto, com foco na extensão do vocabulário adquirido, e dados de processo, cujo objetivo era obter explicações que nos ajudassem a interpretar, mais claramente, os resultados obtidos através da análise dos dados anteriores, realizamos um estudo quantitativo e um estudo qualitativo. No primeiro, aplicamos duas baterias de quatro testes de vocabulário, em dois pontos distintos no tempo, cujos resultados foram analisados estatisticamente através das técnicas do teste-t e do chi-square. Os dados de processo foram coletados através de gravações em fitas de vídeo e foram analisados qualitativamente. Ambas as análises se complementaram e forneceram-nos valiosas evidências em relação às questões investigadas, evidências essas que um método de pesquisa, sozinho, não teria condições de nos dar. Uma delas indica que o TPR é eficaz para o ensino do vocabulário em LE porque mantém uma alta motivação em sala de aula. Ao término deste estudo, apresentamos algumas contribuições referentes ao ensino-aprendizagem do léxico, em contextos formais de ensino, e à aplicação do TPRAbstract: This research concerns the acquisition of vocabulary in a foreign language (FL) among students who are just beginning to study English in a formal instruction context, that is, children who are attending the fifth grade of Ensino Fundamental. The need of this study emerged from a problem detected among students in their first year of Ensino Médio, who are not able to deal, suceessfully, with the task of reading comprehension in the target language due to a lack of a well known threshold vocabulary. To investigate this problem, we acted as a researcher-teacher, in a public school, during one year, applying the Total Physical Response (TPR) technique to teach the target vocabulary. As we were aiming to collect both product and process data, we developed two different studies: a quantitative one, with a focus on the vocabulary size acquired by the students, and a qualitative one, with a focus on acquiring some information which could help us better understand the results obtained through the analysis of the prior data. In the first study, two batteries of four vocabulary tests were taken by the students at two distinet points in time. The results of these tests were statistically. analysed by using the t-test and the chisquare technique. The process data were collected through. video recording and were qualitatively analysed. Both analyses complemented one another and showed us interesting aspects concerning the topic being investigated; these aspects could not be noticed if we had used only one research method. One of these aspects suggests that the efficacy of TPR in teaching vocabulary is closely related to the existence of a high motivation in the classroom. At the end of this study, we present some contributions, concemed with the vocabulary teaching-Icaming process in a formal instruction context and through the use of TPRMestradoEnsino-Aprendizagem de Segunda Lingua e Lingua EstrangeiraMestre em Linguística Aplicad