Main Results of Phase IV BEMUSE Project: Simulation of LBLOCA in an NPP

Phase IV of BEMUSE Program is a necessary step for a subsequent uncertainty analysis. It includes the simulation of the reference scenario and a sensitivity study. The scenario is a LBLOCA and the reference plant is Zion 1 NPP, a 4 loop PWR unit. Thirteen participants coming from ten different countries have taken part in the exercise. The BEMUSE (Best Estimate Methods plus Uncertainty and Sensitivity Evaluation) Programhas been promoted by theWorking Group on AccidentManagement and Analysis (WGAMA) and endorsed by the Committee on the Safety of Nuclear Installations (CSNI). The paper presents the results of the calculations performed by participants and emphasizes its usefulness for future uncertainty evaluation, to be performed in next phase. The objectives of the activity are basically to simulate the LBLOCA reproducing the phenomena associated to the scenario and also to build a common, well-known, basis for the future comparison of uncertainty evaluation results among different methodologies and codes. The sensitivity calculations performed by participants are also presented. They allow studying the influence of different parameters such as material properties or initial and boundary conditions, upon the behaviour of the most relevant parameters related to the scenario

Analyse des signaux pour un dispositif de mesure et de stimulation du système nerveux central

- Un des enjeux actuels en Neurosciences est de pouvoir enregistrer simultanément les activités d'un grand nombre de cellules au sein de grands réseaux de neurones, et de pouvoir stimuler de manière dynamique ces réseaux afin d'en contrôler les activités. Le but du projet Neurocom est de réaliser un système multiélectrode haute densité intégré sur silicium, permettant d'enregistrer et de stimuler de grands réseaux de neurones in vitro. Ce dispositif sera constitué d'une microstructure d'électrodes stérilisable hybridée sur un circuit analogique intégré (préamplification, filtrage, multiplexage, stimulation), lui-même interfacé via une carte numérique de commande et acquisition reliée à un PC. Afin de pouvoir mieux appréhender les phénomènes bioélectriques et électrochimiques à l'interface capteur et donc mieux spécifier le cahier des charges et l'architecture du système, la maquette de test NEUROCOM1 a été conçue en électronique discrète et est actuellement utilisée pour conduire différents tests

Photovoltaic restoration of sight with high visual acuity

Patients with retinal degeneration lose sight due to the gradual demise of photoreceptors. Electrical stimulation of surviving retinal neurons provides an alternative route for the delivery of visual information. We demonstrate that subretinal implants with 70-μm-wide photovoltaic pixels provide highly localized stimulation of retinal neurons in rats. The electrical receptive fields recorded in retinal ganglion cells were similar in size to the natural visual receptive fields. Similarly to normal vision, the retinal response to prosthetic stimulation exhibited flicker fusion at high frequencies, adaptation to static images and nonlinear spatial summation. In rats with retinal degeneration, these photovoltaic arrays elicited retinal responses with a spatial resolution of 64 ± 11 μm, corresponding to half of the normal visual acuity in healthy rats. The ease of implantation of these wireless and modular arrays, combined with their high resolution, opens the door to the functional restoration of sight in patients blinded by retinal degeneration

Transition Metal-Catalysed, Direct and Site-Selective N1-, C2-or C3-Arylation of the Indole Nucleus: 20 Years of Improvements

Joucla, Lionel Djakovitch, LaurentThe direct and site-selective transition metal-catalysed N1-, C2- or C3-arylations of indoles have been the subject of almost continuous improvements since their discovery in early 1980s. This research area is mainly motivated by the biological relevance of this class of compounds in order to propose catalytic alternative syntheses to the well known methodologies involving the formation of the indole ring like the Fischer, Larock, Cacchi, Lautens etc. reactions. Since the late 1990s it has experienced new impulses related to the intensive development of catalytic C-H activation. Today, through the intensive studies of Buchwald and Hartwig, the N1-arylation of indoles has reached sufficient maturity for both academic and industrial applications. On the other hand, the selective C2- or C3-arylation of indoles, initiated by Ohta in the middle 1980s, has become a hot research area these last years following the reports of Sames. Surprisingly, only few reports concern the use of heterogeneous catalysts; however, the application of these emerging methodologies seems to be related to the discovery of industrially attractive systems

ON THE WAY TO LIGANDLESS PD-CATALYTIC SYSTEM FOR SITE-SELECTIVE INDOLE ARYLATION ON WATER

International @ BIOVERT+LDJInternational audienceNon

Arylation directe et sélective d'indoles libres dans l'eau.

nationa

Innovative one-pot heterogeneous Pd-catalysed synthesis of stylbenes, bibenzyls and bis(bibenzyls).

internationa

Heterogeneously Pd/C catalysed procedure for the vinylation of aryl bromides

Joucla, Lionel Cusati, Giuseppe Pinel, Catherine Djakovitch, LaurentHeterogeneous Pd/C catalyst was applied to the Suzuki-Miyaura vinylation of various aryl and heteroaryl halides under aerobic and mild reaction conditions [1.0 mmol aryl halide, 1.5 mmol potassium vinyltrifluoroborate, 3.0 mmol K3PO4 center dot H2O, 0.1 mol% Pd/C-(EVO), 1 mL NMP, 100 degrees C, 24 h]. Useful isolated yields (57-73%) were achieved. In some cases, the catalytic system should be tuned to face the reactivity of the aryl halides: while 0.1 mol% Pd/C is sufficient for almost all aryl bromides, 1.0 mol% Pd/C was used for free phenols. The heterogeneous catalyst was proved to be stable upon several catalytic cycles: however, the results showed that this was dependent on addition of the base. Hot-filtration experiment indicates that the activity was mainly due to leached Pd-species, indicating that the Pd/C catalyst acts as a palladium reservoir. (c) 2009 Elsevier B.V. All rights reserved

Efficient heterogeneous vinylation of aryl halides using potassium vinyltrifluoroborate

International audienceAn efficient heterogeneously palladium catalysed procedure for the vinylation of aryl iodides and bromides is reported. Using common reaction conditions (Pd/C 2 mol %, AcONa3H2O, NMP or NMP/H2O), good to complete conversions (40–100%) with high selectivities (79–100%) towards the expected vinylaromatic were achieved