Schèmes de périodisation en histoire de l’art : enjeux intellectuels et pratiques publiques

Curieusement, la notion de périodisation en histoire de l’art n’a pas été très souvent examinée, à la différence d’autres approches ou outils, comme les gender studies ou la monographie. Seuls peuvent être cités quelques textes de réflexion, qui démontrent les apories de cet outil ou cherchent à élaborer une autre notion du temps à partir des objets ou de la géographie, et des essais démontrant l’application de cet outil, notamment pour l’Italie. Pourtant, la périodisation est un outil famili..

Phenotypic spectrum of fetal Smith-Lemli-Opitz syndrome.

International audienceThe Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive multiple congenital malformation syndrome caused by dehydrocholesterol reductase deficiency. The diagnosis is confirmed by high 7- and secondarily 8-dehydrocholesterol levels in plasma and tissues and/or by detection of biallelic mutations in the DHCR7 gene. The phenotypic spectrum of SLOS is broad, ranging from a mild phenotype combining subtle physical anomalies with behavioral and learning problems, to a perinatally lethal multiple malformations syndrome. The fetal phenotype of SLOS has been poorly described in the literature. We report a series of 10 fetuses with molecularly proven SLOS. Even in young fetuses, the facial dysmorphism appears characteristic. Genital abnormalities are rare in 46,XX subjects. Gonadal differentiation appears histologically normal and in agreement with the chromosomal sex, contrary to what has been previously stated. We observed some previously unreported anomalies: ulnar hypoplasia, vertebral segmentation anomalies, congenital pulmonary adenomatoid malformation, fused lungs, gastroschisis, holomyelia and hypothalamic hamartoma. This latter malformation proves that SLOS phenotypically overlaps with Pallister-Hall syndrome which remains clinically a major differential diagnosis of SLOS

INTERET DE L'ECHOGRAPHIE MODE B DANS LE DIAGNOSTIC DES SINUSITES MAXILLAIRES CHEZ LES PATIENTS INTUBES - VENTILES (COMPARAISON A LA TOMODENSITOMETRIE)

AMIENS-BU Santé (800212102) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Synthesis and Second Harmonic Generation microscopy of nonlinear optical efficient hybrids nanoparticles embedded in polymer films. Evidence for Intra and Inter nanoparticles orientational synergy

International audienc

Green composites based on thermoplastic starches and various natural plant fibers: Impacting parameters of the mechanical properties using machine-learning

peer reviewedMultivariate analyses on formulation and mechanical behavior of nonwoven and nonoriented natural fibers reinforced thermoplastic starch (TPS) composites were performed. Glycerol and water were considered as TPS plasticizers. Fibers composition (i.e., cellulose, hemicellulose, lignin), fibers morphology (fibers length), starch composition (i.e., amylose/amylopectin ratio) as well as the processing conditions (i.e., temperature, rotor speed, relative humidity during aging) were evaluated for their ability to affect the elastic modulus, tensile strength, and elongation at break of the final materials. Multivariate linear regressions were computed to unveil the importance of each variable on the mechanical behavior. Fibers composition impacted the most the models: cellulose maximization improved the elastic modulus and tensile strength while lignin reduced the elastic modulus and hemicellulose decreased the tensile strength. TPS plasticizers, temperature, and rotor speed of the process were negatively impacting the elastic modulus but in a lesser extent than the fiber composition. Within the range of the created database, the selected variables and attributed coefficients were permitted to explain the variability. The produced models revealed that complex and yet uninvestigated interactions are to be considered within TPS-based biocomposites. Therefore, this work discusses and suggests a “must-have” list of variables for comparable analyses of new TPS-based biocomposites using natural fibers as reinforcement

Speciation of residual carbon contained in UO2_2

International audienceUO$_2$ powders were synthesized thanks to oxalic precipitation (platelet morphology) and sol-gel route and completely characterized. A secondary phase was found in addition of the oxide depending on the calcination atmospheres. This phase has been identified by Raman spectroscopy as graphitic material (i.e. carbon-based secondary compound) and quantified by thermogravimetric analyses. Its amount varies with the calcination atmosphere. The presence of this secondary phase has no significant effect on the lattice parameter and its specific surface area

Entre valorisation, conservation et dépérissement: la gestion de nos chênaies à la croisée des chemins

Une crise sanitaire touche les peuplements de chêne, essentiellement ardennais. Des phénomènes de dépérissement sont observés de plus en plus souvent depuis 2010 pour atteindre aujourd'hui des proportions inquiétantes. En Ardenne, en 2014, près de 40% des chênes pédonculés étaient affectés par le dépérissement. Les dépérissements sont provoqués par un ensemble de stress biotiques ou abiotiques, simultanés ou séquentiels. La sylviculture joue probablement également un rôle (inadéquation avec la station, surface terrière trop élevée ...). Mais même s'il y a crise, il n'y a pas urgence. Aucune dégradation significative du bois n'est observée au cours du dépérissement ni même jusqu'à 3 ou 4 ans après la mort de l'arbre. L'exploitation rapide et désordonnée des arbres morts n'est pas indispensable, d'autant qu'elle pourrait provoquer plus de dégâts que le dépérissement lui-même. Les interventions se feront en fonction des enjeux et des objectifs du plan d'aménagement, et selon le taux d'arbres touchés. Le dépérissement des chênes touche largement des arbres qui n'étaient pas en station. Toute information est à relayer auprès de l'OWSF ou de ses partenaires scientifiques afin d'avancer vers la compréhension du phénomène et la meilleure manière de le gérer