Crosstalk Between Innate and T Cell Adaptive Immunity With(in) the Muscle

Growing evidence demonstrates a continuous interaction between the immune system and the skeletal muscle in inflammatory diseases of different pathogenetic origins, in dystrophic conditions such as Duchenne Muscular Dystrophy as well as during normal muscle regeneration. Although one component of the innate immunity, the macrophage, has been extensively studied both in disease conditions and during cell or gene therapy strategies aiming at restoring muscular functions, much less is known about dendritic cells and their primary immunological targets, the T lymphocytes. This review will focus on the dendritic cells and T lymphocytes (including effector and regulatory T-cells), emphasizing the potential cross talk between these cell types and their influence on the structure and function of skeletal muscle

Réseaux bidimensionnels d'agrégats magnétiques préformés en phase gazeuse

Ce travail de thèse porte sur l'organisation de nanoparticules sur des surfaces grâce à une approche originale basée sur le dépôt à faible énergie d'agrégats, préformés en phase gazeuse (approche Bottom-up), sur substrats de graphite HOPG, fonctionnalisés par des réseaux 2D de défauts créés par faisceau d'ions focalisés nano-FIB (approche Top-down). L'obtention de réseaux 2D d'amas d'agrégats est conditionnée par la diffusion des agrégats déposés et leur sensibilité aux défauts artificiels FIB. Le développement de cette approche passe tout d'abord par des simulations Monte-Carlo réalisées dans le cadre du modèle DDA (Dépôt-Diffusion-Agrégation). Ensuite, sa faisabilité expérimentale est testée avec succès en déposant des agrégats d'or. En particulier, cette étude montre la dépendance des propriétés morphologiques et structurales des défauts FIB en fonction de la dose d'ions. Par ailleurs, la sensibilité des agrégats aux défauts FIB, ainsi que la possibilité de contrôler la taille des amas, la période du réseau et sa géométrie sont analysées. Enfin, en se plaçant dans les conditions optimales permettant la meilleure organisation, notre approche est étendue aux agrégats magnétiques Co50Pt50, candidats potentiels au stockage d'information à ultra-haute densité. Une étude de l'influence du recuit sur les réseaux d'agrégats Co50Pt50 montre une amélioration de la qualité de l'organisation, et surtout une transition de phase des agrégats de la structure A1 vers la structure L10This thesis work focus on the organization of nanoparticles on surfaces by an original approach based on the deposition of preformed nanoclusters in a soft landing process (Bottom-up approach) onto functionalized HOPG-substrate with 2D arrays of defects created by Focused Ion Beam nano-FIB (Top-down approach). To obtain a 2D array of cluster-assembled nanoislands, the deposited nanoclusters must diffuse on the surface and be sensitive to FIB-defects. Then, in order to develop this approach, we first emphasize the predictions of Monte-Carlo simulations including DDA (Deposition-Diffusion-Agregation) model. Next, we successfully test its experimental feasibility by depositing gold preformed nanoclusters. Particularly, this study shows the dependence of morphological and structural properties of FIB-defects on the ion doses. Moreover, the sensitivity of deposited nanoclusters to FIB-defects and the possibility to control the periodicity and the geometry of the nanoparticle arrays as well as the size and the morphology of the cluster-assembled nanoislands were analyzed. Finally, choosing the set of experimental parameters responsible for the nicer organization, we extend our approach to Co50Pt50 magnetic nanoclusters, promising candidates for high-density data storage devices. Post-annealing treatments induce a drastic improvement of the quality of the organization as well as a phase transformation of the supported clusters from A1-phase to the L10-oneLYON1-BU.Sciences (692662101) / SudocSudocFranceF

Evidence of L1(0) chemical order in CoPt nanoclusters: Direct observation and magnetic signature

International audienceWe report the synthesis and characterization of well-defined CoPt clusters with a mean diameter of 3 nm, produced in ultrahigh vacuum conditions following a physical route. Samples made of diluted layers of CoPt clusters embedded in amorphous carbon have been studied by transmission electron microscopy. High-resolution observations have revealed the appearance of L1(0) chemical order upon annealing, even for clusters with a 2 nm diameter, without cluster coalescence. The magnetic properties of both chemically disordered and ordered CoPt clusters embedded in amorphous carbon have then been measured by x-ray magnetic circular dichroism and superconducting quantum interference device magnetometry. Despite a striking change of the Co magnetic moment, the magnetic anisotropy of chemically ordered nanoparticles increases, with respect to the chemically disordered A1 phase, in much lower proportions than what is observed for the bulk

Make EU trade with Brazil sustainable

Brazil, home to one of the planet's last great forests, is currently in trade negotiations with its second largest trading partner, the European Union (EU). We urge the EU to seize this critical opportunity to ensure that Brazil protects human rights and the environment