VLT/NACO infrared adaptive optics images of small scale structures in OMC1

International audienceNear-infrared observations of line emission from excited H 2 and in the continuum are reported in the direction of the Orion molecular cloud OMC1 , using the European Southern Observatory Very Large Telescope UT4 , equipped with the NAOS adaptive optics system on the CONICA infrared array camera. Spatial resolution has been achieved at close to the diffraction limit of the telescope (0. 08 −0. 12) and images show a wealth of morphological detail. Structure is not fractal but shows two preferred scale sizes of 2. (1100 AU) and 1. 2 (540 AU) , where the larger scale may be associated with star formation. Key words. ISM : individual objects : OMC1 – ISM : circumstellar matter – ISM : kinematics and dynamics – ISM : molecules – infrared : IS

Le rôle des connaissances de référence dans la gestion des phases de débat scientifique à l’école primaire en Suisse romande

International audienceCette recherche aborde en premier lieu la question du rôle de l’enseignant et des supports mobilisés lors de la gestion de débats argumentatifs en classe. L’étude s’appuie sur l’élaboration collective et la mise en oeuvre d’une séance de classe avec des élèves de 8-9 ans. Elle vise à comprendre la contribution des connaissances de référence référence (en tant qu’ensemble évolutif de connaissances d’ordre théorique ou empirique, relatives au thème abordé, disponibles à la fois chez le maître et chez les élèves et ayant été publiquement validées) dans l’apparition chez les élèves d’« effets d’argumentation » sur les possibles. Les résultats permettent de caractériser la construction de ces connaissances qui vont permettre, in fine, la production de premières explications du phénomène . Ces explications, comme autant de premières règles, seront ensuite mises à l’épreuve dans le cadre d’une situation-problème. Par ailleurs, cette étude présente le débat scientifique comme un processus interactif de partage des responsabilités entre l’enseignant.e et les élèves. Dans ce contexte et d’un point de vue didactique, les connaissances de référence qu’elles soient de nature empirique ou théorique, jouent le rôle d’arrière-plan commun. La mise en tension des 2 registres (empirique et théorique) permet de construire au fil des interactions langagières des significations partagées. Les élèves participent ainsi pleinement à la validation et l’enseignant, de son côté, s’en tient aux aspects essentiels du savoir en jeu. La mobilisation de ces connaissances de référence lors des phases de débat semble soutenir la gestion par l’enseignante débutante de ces phases interactives qui inquiètent souvent les novices

Influence of the chemical composition variations on densification during the sintering of MOX materials

International audienc

Effect of Carbon During The Sintering of MOX fuels

International audienc

A systematic review of quality indicators for appropriate antibiotic use in hospitalized adult patients

Many quality indicators for appropriate antibiotic use have been developed. We aimed to make a systematic inventory, including the development methodology and validation procedures, of currently available quality indicators (QIs) for appropriate antibiotic use in hospitalized adult patients. We performed a literature search in the Pubmed interface. From the included articles we abstracted i) the indicators developed ii) the type of infection the QIs applied to iii) study design used for the development of the QIs iv) relation of the QIs to outcome measures v) whether the QIs were validated and vi) the characteristics of the validation cohort. Fourteen studies were included, in which 200 QIs were developed. The most frequently mentioned indicators concerned empirical antibiotic therapy according to the guideline (71% of studies), followed by switch from IV to oral therapy (64% of studies), followed by drawing at least two sets of blood cultures and change to pathogen-directed therapy based on culture results (57% of studies). Most QIs were specifically developed for lower respiratory tract infection, urinary tract infection or sepsis. A RAND-modified Delphi procedure was used in the majority of studies (57%). Six studies took outcome measures into consideration during the procedure. Five out of fourteen studies (36%) tested the clinimetric properties of the QIs and 65% of the tested QIs were considered valid. Many studies report the development of quality indicators for appropriate antibiotic use in hospitalized adult patients. However, only a small number of studies validated the developed QIs. Future validation of QIs is needed if we want to implement them in daily practice

NOTE SUR LA VALEUR COMPARÉE DE 4 MÉTHODES PERMETTANT D'ESTIMER L'IMPORTANCE DES MORCEAUX GRAS DANS UNE DÉCOUPE DE PORC

International audienc

Synthesis of a peroxime proliferator activated receptor (PPAR) alpha/gamma agonist via stereocontrolled Williamson ether synthesis and stereospecific S(N)2 reaction of S-2-chloro propionic acid with phenoxides

The stereospecific synthesis of the PPAR alpha/gamma agonist I was accomplished via ethylation of the optically pure tribydroxy derivative 6, itself derived via an enzymatic resolution. The ethylation can be accomplished without epimerization only under strict control of the reaction conditions and the choice of base (sodium tert-amylate), temperature (-30 degrees C), order of addition, and solvent (DMF). The key diastereospecific S(N)2 reaction of the phenol 4 with S-2-chloropropionic acid is best achieved via the sodium phenoxide of 4 derived from Na-0 as the reagent of choice. The structure elucidation and key purification protocols to achieve pharmaceutical purity will also be described