[en] This paper is devoted to the presentation of a numerical scheme for the simulation of gravity currents of non-Newtonian fluids. The two dimensional computational grid is fixed and the free-surface is described as a polygonal interface independent from the grid and advanced in time by a Lagrangian technique. Navier-Stokes equations are semi-discretized in time by the Characteristic-Galerkin method, which finally leads to solve a generalized Stokes problem posed on a physical domain limited by the free surface to only a part of the computational grid. To this purpose, we implement a Galerkin technique with a particular approximation space, defined as the restriction to the fluid domain of functions of a finite element space. The decomposition-coordination method allows to deal without any regularization with a variety of non-linear and possibly non-differentiable constitutive laws. Beside more analytical tests, we revisit with this numerical method some simulations of gravity currents of the literature, up to now investigated within the simplified thin-flow approximation framework

[en] Plants were grown in a controlled environment chamber and fed with a modified Hoagland solution containing nitrate as nitrogen source (N+ medium). Soybeans, 33 days old (flowering stage), 45 and 56 days old (pods formation and filling stages) were used for experimentation. In each experiment, the eight trifoliated leaf (F₈) was exposed to ¹⁴CO₂ (10 μCi; 400 vpm), in the light (80 W x m^-2) for 30 min. After a 6 h chase period (22 - 25⁰C; 80 W x m^-2), the radiocarbon distribution among plant parts was determined and labelled compounds were identified. (orig.)

[en] Buckwheat (Fagopyrum esculentum M.) grown in culture solutions with nitrate as nitrogen source contained high levels of oxalic acid, mainly as insoluble salts; 1-¹⁴C glycolate was an efficient oxalate precursor. When nitrogen source was ammonia, oxalic acid concentrations were very low and large amounts of free amino acids, namely glycine and serine, were detected; 1-¹⁴C glycolate metabolism led to high ¹⁴CO₂ release and important serine labelling, which was also found after incorporation of 1-¹⁴C glycine. Utilization of U-¹⁴C serine did not vary with composition of nutrient solution. These results show differences in buckwheat photorespiratory metabolism in relation with inorganic nitrogen nutrition

[en] Serine, glycerate and glycolate are among the first radioactive compounds when French Bean and Maize leaves are fed with glucose U¹⁴C. Failing to detect radioactive glycine suggests that glycolate so synthesized is unavailable for the photorespiration glycolate pool

[en] Thesis presentations have been organised in sessions which respectively addressed issues related to radiation safety, and to environment and health (urban atmosphere, dry deposition of aerosols, therapeutic benefit of an injection of mesenchymal stem cells, colorectal lesions, role of toll-like receptors (or TLR) in immune orientations induced by an abdominal irradiation. Plenary sessions also addressed these issues. Then sessions addressed issues related to parallel effects in low doses, to the parallel modelling of materials, to containment and aerosols, to neutron spectrometry and dosimetry. Some parallel sessions addressed issues related to geosphere, to severe accidents and fires. A plenary session addressed the Fukushima accident, the related R and D, and future investment. Poster sessions addressed several topics: safety (fire, containment, neutronics, civil engineering, methods), and radiation protection (radionuclide metrology, toxicology, radio-biology, dosimetry).