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Aerial Vision Based Guidance and control for Perception-Less Ground Vehicle
No full textInternational audienc
Teaming up with students to design sustainability education
No full texthttps://www.timeshighereducation.com/campus/teaming-students-design-sustainability-educatio
Synthesis And Magnetic Properties Of Spherical Maghemite Nanoparticles With Tunable Size And Surface Chemistry
No full textInternational audienceWe report the synthesis of uniform populations of spherical maghemite nanoparticles by thermal decomposition of iron precursors, with tunable diameters centered at 3.3, 7.5, and 12.0 nm and tunable surface chemistry. The three stabilizing ligands were fatty acids with three different alkyl chain lengths (18, 12, and 8 carbon atoms). The unprecedented accurate control of the surface chemistry is made possible by the use of three types of iron complexes, that is, iron oleate (C18), iron dodecanoate (C12), and iron octanoate (C8), associated with fatty acid ligands having the same alkyl chain length, that is, oleic acid (C18), dodecanoic acid (C12), and octanoic acid (C8). Since the thermal decomposition of the iron precursor varies with the chain length, no general rules can be applied to control the nanoparticle size, but optimal synthesis conditions have been investigated to induce the growth of nanoparticles with three different surface chemistries, keeping the diameters centered at 3.3, 7.5, and 12.0 nm. Finally, structural characterization of the nine populations of maghemite nanoparticles was performed by transmission electron microscopy and X-ray diffraction, and magnetic properties were determined using SQUID magnetometry
Les savoirs sur la Chine, entre terrain et bibliothèques (XVIe-XIXe siècles)
No full textLe dossier principal de ce nouveau numéro réunit les textes de sept jeunes chercheurs et chercheuses qui étudient la construction et la circulation des savoirs européens sur la Chine, de la Renaissance à la fin du XIXe siècle. À partir de sources en plusieurs langues et de différentes natures – manuscrits, imprimés, objets, estampes, photographies, cartes, principalement conservées à la Bibliothèque nationale de France – les auteur(e)s retracent la circulation des savoirs entre terrain et bibliothèques, entre l’Asie et l’Europe. Les contributions mettent en lumière le rôle et les pratiques d’institutions et d’acteurs variés, qu’il s’agisse de missionnaires, de cartographes, de dramaturges, de diplomates ou encore de marchands
Incidence and risk factors for thromboembolic events in pediatric-onset inflammatory bowel disease: A French population-based study
No full textInternational audienceIntroduction: Patients with inflammatory bowel disease (IBD) are at higher risk of thromboembolic events (TE). In pediatric-onset IBD, more data on incidence and risk factors of venous (VTE) and arterial events (ATE) at the population level are needed to guide thromboprophylaxis.Methods: All patients aged ≤ 16 years diagnosed with Crohn's disease (CD) or ulcerative colitis (UC) between 1988 and 2011 in the prospective EPIMAD population-based registry were followed until 2013. Every TE occurring during the follow-up period was included.Results: A total of 1,344 patients were included: 1,007 with CD and 337 with UC, and a median diagnosis age of 14.3 years. After a median follow-up of 8.3 years, 2 (0.15 %) ATE and 15 (1.1 %) VTE occurred at median age of 20.4 years. The global incidence rate of thromboembolic events was 1.32 per 1000 person-years. Periods of active disease (HR=8.4, p = 0.0002), the 3-month-period following surgery (HR=16.4, p = 0.0002) and hospitalization (HR=21.7, p < 0.0001) were found to be associated with an increased risk of VTE. A lower rate of VTE was found in patients treated with 5-aminosalicylates (HR=0.1, p = 0.002).Conclusion: The risk of TE was low in this population. VTE were strongly associated with active disease, surgery and hospitalization
Valorization of silk by-products for lipopeptide surfactant production using green technologies
No full textInternational audienc
Spatial and mechanical environments regulate the heterogeneity of myonuclei
No full textAbstract Skeletal muscle formation involves tight interactions between muscle cells and associated connective tissue fibroblasts. Every muscle displays the same type of organisation, they are innervated in the middle and attached at both extremities to tendons. Myonuclei are heterogeneous along myotubes and regionalised according to these middle and tip domains. During development, as soon as myotubes are formed, myonuclei at muscle tips facing developing tendons display their own molecular program. In addition to molecular heterogeneity, a subset of tip myonuclei has a fibroblastic origin different to the classical somitic origin, highlighting a cellular heterogeneity of myonuclei in foetal myotubes. To gain insights on the functional relevance of myonucleus heterogeneity during limb development, we used 2D culture and co-culture systems to dissociate autonomous processes (occurring in 2D-cultures) from 3D-spatial environment of tissue development. We also assessed the role of mechanical parameters in myonucleus heterogeneity in paralysed limb muscles. The regionalisation of cellular heterogeneity was lost in 2D cell culture systems and paralyzed muscles. The molecular signature of MTJ myonuclei was also lost a dish and paralysed muscles indicating a requirement of spatial and mechanical input for MTJ formation. Tip genes that maintain their expression in a dish are involved in myofibrillogenesis and myotube attachments. The behaviour of regionalized markers in cultured myotubes and paralyzed muscles allows us to deduce whether the genes intervene in myogenesis, myotube attachment or MTJ formation. Highlights The regionalisation of cellular heterogeneity of myonuclei is lost in cultured myotubes BMP signalling regulates fibroblast nucleus incorporation into cultured myotubes The molecular signature of MTJ myonuclei is lost in cultured myotubes and paralysed muscles Tip genes involved in myofibrillogenesis maintain their regionalised expression in cultured myotube
Principled Explanations for Robust Redistributive Decisions
No full textInternational audienceOrdered weighted averaging (OWA) functions, a.k.a. Generalised Gini Index, are routinely used to obtain fair solutions. However, while they ensure some level of fairness in the result, two remaining questions are why they recommend a given alternative, and how robust is this recommendation. We bring practical and theoretically grounded solutions to these questions, by providing an explanation engine for robust OWA that consists in a normative transitive chain of self-evident arguments, themselves based on the normative properties of the model. We provide a thorough theoretical study of the engine, showing that it is sound and complete with respect to the model, with a theoretical upper bound on the length of the explanation and a tractable algorithm (even though minimizing the length is NP-hard). We also provide experimental evidence that the engine performs well on synthetic data. Thus, we guarantee that an explanation can always be found, and that reasoning according to the provided scheme always produces a valid statement. Moreover, the explanations allow to probe the normative requirements of the model, so as to allow validation, accountability and recourse, that are key components of trustworthy AI
Captage du CO2 par procédé Temperature Swing Adsorption (TSA) assisté par énergie solaire
No full textInternational audienc
HMM non paramétrique piloté par les observations
No full textThe hidden Markov models (HMM) are used in many different fields, to study the dynamics of a process that cannot be directly observed. However, in some cases, the structure of dependencies of a HMM is too simple to describe the dynamics of the hidden process. In particular, in some applications in finance or in ecology, the transition probabilities of the hidden Markov chain can also depend on the current observation. In this work we are interested in extending the classical HMM to this situation. We define a new model, referred to as the Observation Driven-Hidden Markov Model (OD-HMM). We present a complete study of the general non-parametric OD-HMM with discrete and finite state spaces (hidden and observed variables). We study its identifiability. Then we study the consistency of the maximum likelihood estimators. We derive the associated forward-backward equations for the E-step of the EM algorithm. The quality of the procedure is tested on simulated data sets. Finally, we illustrate the use of the model on an application on the study of annual plants dynamics. This works sets theoretical and practical foundations for a new framework that could be further extended, on one hand to the non-parametric context to simplify estimation, and on the other hand to the hidden semi-Markov models for more realism