De la nécessité de disposer d’une puissante bibliothèque scientifique à l’Ecole polytechnique

Un des axes politiques principaux de l’Ecole est l’internationalisation. La réussite de celle-ci suppose la reconnaissance de l’Ecole comme un acteur majeur de la scène scientifico-universitaire mondiale. Les performances du centre de recherches dépendent d’un accès rapide et performant à l’information scientifique. Ceci suppose, à l’évidence, une bibliothèque scientifique centrale de haut niveau, disposant des principales revues scientifiques de chaque discipline et d’un accès performant aux..

Editorial

Lorsque Maurice Bernard m’a proposé d’écrire un éditorial pour ce numéro consacré à l’histoire de la chimie à l’Ecole Polytechnique, il m’a paru tout de suite normal d’accepter. Lors de la mise en place du Département de Chimie actuel en 1986, Maurice Bernard a, en effet, joué un rôle central dans la conception et la gestation de la nouvelle formule. Ce département d’enseignement et de recherche complètement intégré et doté d’une instance d’évaluation globale fonctionne maintenant depuis une ..

De la nécessité de disposer d’une puissante bibliothèque scientifique à l’Ecole polytechnique

Un des axes politiques principaux de l’Ecole est l’internationalisation. La réussite de celle-ci suppose la reconnaissance de l’Ecole comme un acteur majeur de la scène scientifico-universitaire mondiale. Les performances du centre de recherches dépendent d’un accès rapide et performant à l’information scientifique. Ceci suppose, à l’évidence, une bibliothèque scientifique centrale de haut niveau, disposant des principales revues scientifiques de chaque discipline et d’un accès performant aux..

1,2-Dihydrophosphete: A Platform for the Molecular Engineering of Electroluminescent Phosphorus Materials for Light-Emitting Devices

International audienceThe discovery and molecular engineering of novel electroluminescent emitting materials is still a challenge in optoelectronics. In this work, we report on the development of new π-conjugated oligomers incorporating a dihydrophosphete skeleton. Variation of the substitution pattern of 1,2-dihydrophosphete derivatives and chemical modification of their P atoms afford thermally stable derivatives which are suitable emitters to construct organic light-emitting diodes. The optical and the electrochemical properties of these new P-based oligomers have been investigated in detail and are supported by DFT calculations. The OLED devices exhibit good performance and current independent CIE coordinate

Benzofuran-fused Phosphole: Synthesis, Electronic, and Electroluminescence Properties

International audienceA synthetic route to novel benzofuran-fused phosphole derivatives 3-5 is described. These compounds showed optical and electrochemical properties that differ from their benzothiophene analog. Preliminary results show that 4 can be used as an emitter in OLEDs, illustrating the potential of these new compounds for opto-electronic applications

Prions in Milk from Ewes Incubating Natural Scrapie

Since prion infectivity had never been reported in milk, dairy products originating from transmissible spongiform encephalopathy (TSE)-affected ruminant flocks currently enter unrestricted into the animal and human food chain. However, a recently published study brought the first evidence of the presence of prions in mammary secretions from scrapie-affected ewes. Here we report the detection of consistent levels of infectivity in colostrum and milk from sheep incubating natural scrapie, several months prior to clinical onset. Additionally, abnormal PrP was detected, by immunohistochemistry and PET blot, in lacteal ducts and mammary acini. This PrPSc accumulation was detected only in ewes harbouring mammary ectopic lymphoid follicles that developed consequent to Maedi lentivirus infection. However, bioassay revealed that prion infectivity was present in milk and colostrum, not only from ewes with such lympho-proliferative chronic mastitis, but also from those displaying lesion-free mammary glands. In milk and colostrum, infectivity could be recovered in the cellular, cream, and casein-whey fractions. In our samples, using a Tg 338 mouse model, the highest per ml infectious titre measured was found to be equivalent to that contained in 6 µg of a posterior brain stem from a terminally scrapie-affected ewe. These findings indicate that both colostrum and milk from small ruminants incubating TSE could contribute to the animal TSE transmission process, either directly or through the presence of milk-derived material in animal feedstuffs. It also raises some concern with regard to the risk to humans of TSE exposure associated with milk products from ovine and other TSE-susceptible dairy species

Le Larzac à l’heure de l’aménagement

Mathey Marie-Jo, Mathey François. Le Larzac à l’heure de l’aménagement. In: Autogestions, NS N°16, 1984. Parties de campagne. pp. 79-84

The insertion of terminal phosphinidene complexes into the B---H bond of amine and phosphine boranes

Push–pull complexation: Transient terminal phosphinidene complexes [RP[BOND]W(CO)5] insert at 110 °C into the B[BOND]H bonds of L[BOND]BH3 (L = Et3N, Ph3P; see scheme). The reaction is probably driven by an interaction between the nucleophilic boron and the electrophilic phosphorus