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

Human regulatory T cells locally differentiate and are functionally heterogeneous within the inflamed arthritic joint

Objective: Tregs are crucial for immune regulation, and environment-driven adaptation of effector (e)Tregs is essential for local functioning. However, the extent of human Treg heterogeneity in inflammatory settings is unclear. Methods: We combined single-cell RNA- and TCR-sequencing on Tregs derived from three to six patients with juvenile idiopathic arthritis (JIA) to investigate the functional heterogeneity of human synovial fluid (SF)-derived Tregs from inflamed joints. Confirmation and suppressive function of the identified Treg clusters was assessed by flow cytometry. Results: Four Treg clusters were identified; incoming, activated eTregs with either a dominant suppressive or cytotoxic profile, and GPR56 +CD161 +CXCL13 + Tregs. Pseudotime analysis showed differentiation towards either classical eTreg profiles or GPR56 +CD161 +CXCL13 + Tregs supported by TCR data. Despite its most differentiated phenotype, GPR56 +CD161 +CXCL13 + Tregs were shown to be suppressive. Furthermore, BATF was identified as an overarching eTreg regulator, with the novel Treg-associated regulon BHLHE40 driving differentiation towards GPR56 +CD161 +CXCL13 + Tregs, and JAZF1 towards classical eTregs. Conclusion: Our study reveals a heterogeneous population of Tregs at the site of inflammation in JIA. SF Treg differentiate to a classical eTreg profile with a more dominant suppressive or cytotoxic profile that share a similar TCR repertoire, or towards GPR56 +CD161 +CXCL13 + Tregs with a more distinct TCR repertoire. Genes characterising GPR56 +CD161 +CXCL13 + Tregs were also mirrored in other T-cell subsets in both the tumor and the autoimmune setting. Finally, the identified key regulators driving SF Treg adaptation may be interesting targets for autoimmunity or tumor interventions

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

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Effect of Carbon During The Sintering of MOX fuels

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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

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