We studied circadian thyrotropin (TSH) and prolactin (PRL) response to synthetic thyrotropin-releasing-hormone (protirelin) infusion (200μg IV) at 8 am and 11 pm in 35 drug-free inpatients with DSM III-R Major Depressive Episode and in 22 hospitalized controls. In each group, maximum TSH and PRL responses were lower at 8 am than at 11 pm. The difference between 11 pm-ΔTSH and 8 am-ΔJTSH (ΔΔTSH) was significantly lower in depressed patients compared to controls. No such blunting was observed in PRL responses to protirelin in depressed patients. In the overall population, TSH response to protirelin (ie8 am-ΔTSH, 11 pm-ΔTSH, ΔΔTSH) correlated significantly with TSH circadian parameters (ie mesor and amplitude). These correlations were also observed with PRL (except for ΔΔPRL). TSH mesor and amplitude were lower in depressives than in controls. In contrast, PRL mesor and amplitude were not significantly different between diagnostic groups. ΔΔTSH is thus a chronobiological refinement to the measure of thyroid axis dysfunction in major depression. The blunted TSH response to protirelin suggests that the TRH receptors of the pituitary thyrotrophs are hyposensitive in major depression.

There are plentiful of oolitic iron ore resources on the earth, which cannot be currently exploited because of great difficulties for beneficiating the ore. In this work, the selective fragmentation of a Chinese oolitic iron ore (which fragments ore particles along the interfaces of iron and gangue minerals) through microwave was studied in order to liberate the iron minerals at a coarse particle size and thus to effectively concentrate the iron minerals from the ore. The experimental results have shown that a large amount of fractures on the oolitic iron ore were formed along iron and gangue mineral interfaces after being treated by microwave radiation at an appropriate frequency and potential. Following a microwave treatment, the oolitic iron ore was ground by using a ball vertimill. It was indicated that the pretreatment increased the liberation of the iron and gangue minerals at the same particle size, about 10-20% and 10-30% respectively.

Plusieurs laboratoires et centres techniques ont commencé à travailler sur la possibilité de réaliser des composés multimatériaux via la Métallurgie des Poudres. Dans un tel cas, ce procédé permet d'éviter le problème de l'assemblage et d'obtenir une production aux cotes. Les compressions dynamique (CGV) et conventionnelle sont deux voies possibles qui pourront être comparées grâce à une presse de laboratoire instrumentée pour l'analyse des phénomènes. Pour certaines poudres, la CGV permet d'améliorer les propriétés à vert et de modifier favorablement les conditions de frittage. La compression est suivie d'un frittage conventionnel. Différents types de poudres (poudres métalliques, poudres dures mais également des poudres céramiques) sont utilisés dans ce projet permettant ainsi de proposer de nombreuses applications. Cette présentation montre les premiers résultats obtenus par le groupe de recherche.

Metallic copper nanostructured particles were synthesised by thermal decomposition of a CuC2O4 precursor obtained via the precipitation reaction between Cu(NO3)2·6H2O and Na2C2O4 in the present of hydroxyl propyl methyl cellulose (HPMC). X-ray diffraction (XRD), high resolution scanning electron microscopy (HRSEM) and thermogravimetric analysis (TG) were used to characterise the particles and their evolution during the transformation to metallic copper. We highlight the nanostructured nature of the oxalate precursor, which is made up of anisotropic nanosized buildings blocks (25nm by 40nm). These produce an anisotropy in the oxalate particle and influence the decomposition pathway. The results show the evolution of the nanostructure as a function of degree of reaction and a possible kinetic model is discussed.