Selective conversion of nitroarenes using a carbon nanotube-ruthenium nanohybrid

International audienceRuthenium nanoparticles were assembled on carbon nanotubes and the resulting nanohybrid was used in the hydrazine-mediated catalytic hydrogenation of various nitroarenes, at room temperature. Depending on the solvent, a selective transformation occurred, giving either access to the corresponding aniline or hydroxylamine derivative

Room temperature Suzuki coupling of aryl iodides, bromides, and chlorides using a heterogeneous carbon nanotube-palladium nanohybrid catalyst

International audiencePalladium nanoparticles were immobilized on multi-walled carbon nanotubes by a layer-by-layer approach, resulting in a well-defined assembly. The nanohybrid was found effective in promoting Suzuki cross couplings of various halogenated aromatics, including chlorinated ones, with arylboronic acids under sustainable conditions. The heterogeneous catalyst could also easily be recovered from the reaction mixture and reused with no loss of activity over several cycles

New insights into the origin of the B genome of hexaploid wheat: Evolutionary relationships at the SPA genomic region with the S genome of the diploid relative Aegilops speltoides

<p>Abstract</p> <p>Background</p> <p>Several studies suggested that the diploid ancestor of the B genome of tetraploid and hexaploid wheat species belongs to the <it>Sitopsis </it>section, having <it>Aegilops speltoides </it>(SS, 2n = 14) as the closest identified relative. However molecular relationships based on genomic sequence comparison, including both coding and non-coding DNA, have never been investigated. In an attempt to clarify these relationships, we compared, in this study, sequences of the Storage Protein Activator (SPA) locus region of the S genome of <it>Ae. speltoides </it>(2n = 14) to that of the A, B and D genomes co-resident in the hexaploid wheat species (<it>Triticum aestivum, AABBDD</it>, 2n = 42).</p> <p>Results</p> <p>Four BAC clones, spanning the SPA locus of respectively the A, B, D and S genomes, were isolated and sequenced. Orthologous genomic regions were identified as delimited by shared non-transposable elements and non-coding sequences surrounding the SPA gene and correspond to 35 268, 22 739, 43 397 and 53 919 bp for the A, B, D and S genomes, respectively. Sequence length discrepancies within and outside the SPA orthologous regions are the result of non-shared transposable elements (TE) insertions, all of which inserted after the progenitors of the four genomes divergence.</p> <p>Conclusion</p> <p>On the basis of conserved sequence length as well as identity of the shared non-TE regions and the SPA coding sequence, <it>Ae speltoides </it>appears to be more evolutionary related to the B genome of <it>T. aestivum </it>than the A and D genomes. However, the differential insertions of TEs, none of which are conserved between the two genomes led to the conclusion that the S genome of <it>Ae. speltoides </it>has diverged very early from the progenitor of the B genome which remains to be identified.</p

L'abandon : un acte, deux approches

Boudet Caroline. L'abandon : un acte, deux approches. In: Histoire, économie et société, 1987, 6ᵉ année, n°3. L'enfant abandonné. pp. 361-372

L'abandon dans la littérature française du XIXe siècle. L'histoire des deux victimes

Caroline Boudet, L'abandon dans la littérature française du XIXe siècle. L'histoire des deux victimes, p. 249-258. L'approche de l'abandon dans l'évocation littéraire romanesque ou théâtrale pose bien des problèmes de méthode. Il n'est pas facile de repérer les œuvres centrées sur l'abandon, il n'est pas aisé non plus de généraliser le message d'intrigues diversement rocambolesques. Un point commun semble pourtant se dégager de ces récits très variés. D'un côté la mère, bien née ou prolétaire, bénéficie d'une grande compassion pour ne pas dire de compréhension : on ne veut pas lui refuser l'instinct maternel. Attitude plus ambiguë à l'égard de l'enfant (sauf s'il est issu de la bonne société). Il est souvent décrit sous des traits déplaisants et inquiétants. Il fait peur parce qu'il est fruit de la débauche. (v. au verso) Cette approche littéraire généralement mal informée contraste avec l'opinion des penseurs sociaux d'abord préoccupés de sauver l'enfant, parfois en recommandant de le soustraire à l'influence de sa mère.Boudet Caroline. L'abandon dans la littérature française du XIXe siècle. L'histoire des deux victimes. In: Enfance abandonnée et société en Europe, XIVe-XXe siècle. Actes du colloque international de Rome (30 et 31 janvier 1987) Rome : École Française de Rome, 1991. pp. 249-258. (Publications de l'École française de Rome, 140

Etude de surfaces vicinales ordonnées par diffusion centrale des rayons X sous incidence rasante. Nouveaux développements sur la ligne BM02 à l'ESRF

National audienc

Vasarely painting at the nanoscale on sapphire crystals

International audienceWe demonstrate that convenient thermal treatment of a specific sapphire vicinal surface can induce the formation of a fully two-dimensional (2D) ordered surface made of a periodic assembly of (006) facets. The similarity between the resulting surface topography and patterns represented in the "Hexagon series" of paintings by Vasarely is really striking! We thus propose to call these surfaces as "nanoscaled Vasarely surfaces". We also show that the self-organisation process, which is driven by the minimisation of the free energy of a closed system, results in a quasi-linear isothermal growth of the facets' surface area over time

Five-year follow-up on a sample of gamblers: predictive factors of relapse

International audienceAbstract Background and Aims Few studies have been conducted on the long-term evolution of gambling disorder (GD). The aim of this study was to identify factors that could predict GD relapse. Methods Data were part of a dataset from a large 5-year cohort of gamblers who were assessed at inclusion and each year thereafter. Participants were recruited from an outpatient addiction treatment center, from various gambling places and through the press. For this specific study, inclusion criteria included (i) transitioning from GD to recovery at a follow-up time and (ii) undergoing at least one follow-up visit afterwards. Participants were evaluated using a structured clinical interview and self-report questionnaires assessing sociodemographic, gambling and clinical characteristics. “Relapse” was defined as the presence of GD (according to the DSM-5) at the N+1 th visit following the absence of GD at the N th visit. A Markov model-based approach was employed to examine predictive factors associated with relapse at a subsequent follow-up visit. Results The sample consisted of 87 participants, aged 47.6 years (sd = 12.6), who were predominantly male (65%). Among the participants, 49 remained in recovery, whereas 38 relapsed. Participants who reported not having experienced at least one month of abstinence and those with a low level of self-directedness at the previous follow-up visit were more likely to relapse. Conclusions Our findings suggest the existence of factors that are predictive of relapse in individuals with GD who had previously achieved recovery. These results can inspire the development of measures to promote long-term recovery