Offre de sport et théorie du capital humain. Une application aux pays de l'Europe de l'Est

Cet article analyse l'incidence de la transition des pays de l'Europe de l'Est d'un système d'économie planifiée vers une économie de marché sur leurs performances sportives. Dans la première partie, un modèle, basé sur la théorie du capital humain, est développé afin d'expliquer les choix des individus en matière de pratiques sportives. Cette approche théorique est ensuite testée pour les pays à économie de marché dans le cadre de trois sports particuliers : le tennis, le football et les disciplines olympiques. Finalement, en utilisant les paramètres obtenus dans ces estimations, des prévisions sont émises concernant les performances sportives que les pays de l'Europe de l'Est obtiendront s'ils adoptent un système d'économie de marché. Cette analyse permet également de prévoir les performances sportives que l'Allemagne de l'Est et de l'Ouest réaliseront après leur réunification

Homogeneous light stimulation of melanopsin and cones with a Maxwellian view device for the human eye

We designed and tested a device to stimulate specifically one photoreceptor type, or a combination of some of them, of the human eye by using up to six primaries. The device produces a homogeneous light field over 40° which is projected onto the retina through a Maxwellian view optical system. It avoids the use of an artificial pupil, does not need pupil dilation and retinal illumination can be easily controlled. We successfully tested it with four primaries for melanopsin and S-cone stimulation while maintaining other photoreceptors at a fixed level in photopic regime

PP2A phosphatase acts upon SAS-5 to ensure centriole formation in C. elegans embryos.

International audienceCentrosome duplication occurs once per cell cycle and ensures that the two resulting centrosomes assemble a bipolar mitotic spindle. Centriole formation is fundamental for centrosome duplication. In Caenorhabditis elegans, the evolutionarily conserved proteins SPD-2, ZYG-1, SAS-6, SAS-5, and SAS-4 are essential for centriole formation, but how they function is not fully understood. Here, we demonstrate that Protein Phosphatase 2A (PP2A) is also critical for centriole formation in C. elegans embryos. We find that PP2A subunits genetically and physically interact with the SAS-5/SAS-6 complex. Furthermore, we show that PP2A-mediated dephosphorylation promotes centriolar targeting of SAS-5 and ensures SAS-6 delivery to the site of centriole assembly. We find that PP2A is similarly needed for the presence of HsSAS-6 at centrioles and for centriole formation in human cells. These findings lead us to propose that PP2A-mediated loading of SAS-6 proteins is critical at the onset of centriole formation

Correlative multicolor 3D SIM and STORM microscopy

Within the last decade, super-resolution methods that surpass the diffraction limit of light microscopy have provided invaluable insight into a variety of biological questions. Each of these approaches has inherent advantages and limitations, such that their combination is a powerful means to transform them into versatile tools for the life sciences. Here, we report the development of a combined SIM and STORM setup that maintains the optimal resolution of both methods and which is coupled to image registration to localize biological structures in 3D using multicolor labeling. We utilized this workflow to determine the localization of Bld12p/CrSAS-6 in purified basal bodies of Chlamydomonas reinhardtii with utmost precision, demonstrating its usefulness for accurate molecular mapping in 3D. (C) 2014 Optical Society of Americ

Nostalgia for Film: The Shift from Mechanical to Digital Cinema Projection

Today, cinema is digital: 95 percent of all movie theatres worldwide are equipped with digital projection, and, to an overwhelmingly high degree, the films are shot with digital cameras. But still, among filmmakers and critics, the debate on whether photochemical film stock and mechanical projection of film prints are aesthetically superior continues, since there is little scientific evidence to back up either point of view. To date the question as to whether narrative films are perceived in different ways by a cinema audience depending on the projection or recording technology used, has hardly been examined. This paper focuses on the influence of analog mechanical projection and digital projection on the audience. Empirical data gained from audience experiments show that mechanical projection of film prints produced higher levels of emotional reactions. The results suggest that the specific characteristics of mechanical projection – flickering lights and image instability – has a nostalgic effect which seems related to the viewer’s memory of a traditional cinema experience