Effets de l'eutypiose sur des feuilles de Vitis vinifera cv. Cabernet Sauvignon. Etude cytologique

Effects of Eutypa dieback on the leaves of Vitis vinifera cv. Cabernet Sauvignon. Cytological studiesThe fungus Eutypa lata only grows in lignified wood (trunk and arms) and causes at a distance typical symptoms on the leaves of Vitis vinifera cv. Cabernet Sauvignon, a very sensitive variety. For the first time, lesions induced in vivo in leaf cells were examined by transmission electron microscopy. The main alterations of ultrastructure are depending on the level of disease. In the cells of slightly affected leaves, the enlarged chloroplasts show dilated thylakoids with a lowered electron density and sometimes contain very large starch grains. In the severely affected leaves, the cells are completely disorganized, with plasmalemma retraction, chloroplast degradation, cytoplasm lysis and endomembrane breakdown. These results suggest that structural decline of the photosynthetic system can be responsible, at least partly, for the death of Cabernet Sauvignon grapevines

Development of a new bench for puncturing of irradiated fuel rods in STAR hot laboratory

A new device for puncturing of irradiated fuel rods in commercial power plants has been designed by Fuel Research Department of CEA Cadarache in order to provide experimental data of high precision on fuel pins with various designs. It will replace the current set-up that has been used since 1998 in hot cell 2 of STAR facility with more than 200 rod puncturing experiments. Based on this consistent experimental feedback, the heavy-duty technique of rod perforation by clad punching has been preserved for the new bench. The method of double expansion of rod gases is also retained since it allows upgrading the confidence interval of volumetric results obtained from rod puncturing. Furthermore, many evolutions have been introduced in the new design in order to improve its reliability, to make the maintenance easier by remote handling and to reduce experimental uncertainties. Tightness components have been studied with Sealing Laboratory Maestral at Pierrelatte so as to make them able to work under mixed pressure conditions (from vacuum at 10-5 mbar up to pressure at 50 bars) and to lengthen their lifetime under permanent gamma irradiation in hot cell. Bench ergonomics has been optimized to make its operating by remote handling easier and to secure the critical phases of a puncturing experiment. A high pressure gas line equipped with high precision pressure sensors out of cell can be connected to the bench in cell for calibration purposes. Uncertainty analyses using Monte Carlo calculations have been performed in order to optimize capacity of the different volumes of the apparatus according to volumetric characteristics of the rod to be punctured. At last this device is composed of independent modules which allow puncturing fuel pins out of different geometries (PWR, BWR, VVER). After leak tests of the device and remote handling simulation in a mock-up cell, several punctures of calibrated specimens have been performed in 2016. The bench will be implemented soon in hot cell 2 of STAR facility for final qualification tests. PWR rod punctures are already planned for 2018

Effet de la texture et du potentiel hydrique des sols sur l'expression du charbon des inflorescences du mais (Graminees, Poaceae)

National audienc

Comportement de la muqueuse intestinale vis-à-vis d'entéro-bactéries marquées par 59Fe. Etude autoradiographique chez le Lapin

International audienc

Pollen cytoplasmic granules induce heterogeneous nucleation of water droplets at low supersaturation

International audienc