Chez les plantes, la croissance est essentielle à la régulation de la forme de tout organe en développement. A l'échelle de la cellule, la croissance résulte de la compétition entre la pression interne de la cellule et la rigidité de sa paroi. Des hétérogénéités de ces grandeurs à l'échelle du tissu mènent alors à une croissance différentielle puis à des mouvements à l'échelle de l'organe entier. Ces mouvements macroscopiques peuvent être interprétés comme une manifestation des processus de croissance microscopiques. Nous proposons de mettre à profit ce lien entre croissance et mouvements afin d'approcher la croissance d'une nouvelle manière : de l'organe à la cellule. Nos travaux portent sur les feuilles composées d'Averrhoa carambola qui montrent deux mouvements typiques des feuilles en croissance,le déroulement et la nutation. Nous montrons dans un premier temps que la forme de la feuille en croissance est régulée de manière active. Nous étudions ensuite la cinématique du déroulement et de la nutation. Ce faisant, nous mettons en évidence une relation particulière entre croissance et croissance différentielle à partir de laquelle nous construisons un modèle cinématique de nutation. Conformément à de précédents résultats, ce modèle suggère que la croissance peut s'accompagner de contractions locales. Enfin, à l'échelle du tissu, la mécanique des parois cellulaires et leur composition sont étudiées. Nos résultats révèlent des hétérogénéités spatiales de ces deux paramètres au sein de la feuille, potentiellement cohérents avec la direction du mouvement de nutation. / In plants, growth is essential to the shape regulation of developing organs. It is also the key for every plant to adapt to its environment. At the cell level, growth relies on a competition between the inner pressure of the cell and the rigidity of its cell wall. Heterogeneities of these quantities across the tissue can result in differential growth and lead to motions of the whole organ. These macroscopic motions can thus be read as an outward signal of the cellular mechanisms underlying shape regulation and growth itself. Here, we propose to take benefit from this link between growth and motions to gain a new insight on growth through a multiscale approach, from the organ to the cell wall. We focus on the compound leaves of Averrhoa carambola which display two marked motions, unfurling and nutation, widespread among developing leaves. First, we show that the shape of the leaf results from an active regulation of its macroscopic mechanical properties. The kinematics of the two latter motions are then compared to the associated growth. Doing so, we put forward the specific patterns of growth and differential growth underlying the development of the leaf. Based on these results, we build a kinematic model for nutation which, accordingly with previous findings, suggests the occurrence of local contractions during growth. At the cell wall level, our results reveal spatial heterogeneities of both its rigidity and biochemical status within the leaf. These heterogeneities might be consistent with the direction of the nutation.

Sweden. 1980. The term ‘video violence’ becomes public through the debates show Studio S. The show urges and obligates politicians to stop, regulate and ban video films with violent content from the market. 29 years later, the debates show Debatt raises concerns regarding a similar topic, ‘video game violence’. Both shows were produced and aired by the Public Service channels of Sveriges Television in Sweden. The purpose of this thesis was to study and examine if the media encourages and nourishes moral panics to the general public through debates shows. How does the host/journalist interact to steer the debate to the media agenda and how has the power structure changed in the debate genre over the years? Do the media nurture the root of moral panics? We based the study on a qualitative content analysis. We analyzed one episode from each of the two debate shows Studio S and Debatt. The method of analysis we used was discourse analysis with emphasis on relations and power structures. We also analyzed the episodes by using Goode and Ben-Yehudas five criteria’s for creating moral panic. The study shows that both debates shows fail to mention the problem in a larger societal context. They tend to only portray a scapegoat. Furthermore, they often show one-sided and violent sequences from the cultural phenomena. They use discourses to maintain the firm power in the debates to fulfill their pre-constructed bias agenda. We’ve also observed that it has become much more difficult for a moral panic to gain momentum compared with 1980, because of the medias decentralization.

<p>Sweden. 1980. The term ‘video violence’ becomes public through the debates show <em>Studio S</em>. The show urges and obligates politicians to stop, regulate and ban video films with violent content from the market. 29 years later, the debates show <em>Debatt </em>raises concerns regarding a similar topic, ‘video game violence’. Both shows were produced and aired by the Public Service channels of Sveriges Television in Sweden.</p><p>The purpose of this thesis was to study and examine if the media encourages and nourishes moral panics to the general public through debates shows. How does the host/journalist interact to steer the debate to the media agenda and how has the power structure changed in the debate genre over the years? Do the media nurture the root of moral panics?</p><p>We based the study on a qualitative content analysis. We analyzed one episode from each of the two debate shows <em>Studio S</em> and <em>Debatt</em>. The method of analysis we used was discourse analysis with emphasis on relations and power structures. We also analyzed the episodes by using Goode and Ben-Yehudas five criteria’s for creating moral panic.</p><p>The study shows that both debates shows fail to mention the problem in a larger societal context. They tend to only portray a scapegoat. Furthermore, they often show one-sided and violent sequences from the cultural phenomena. They use discourses to maintain the firm power in the debates to fulfill their pre-constructed bias agenda. We’ve also observed that it has become much more difficult for a moral panic to gain momentum compared with 1980, because of the medias decentralization.</p>