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Automédication
No full textInternational audienceL'automédication correspond à l'utilisation d'un ou de plusieurs médicaments sans l'intervention d'un médecin ni nécessairement le conseil d'un pharmacien ou d'un autre professionnel de santé, dans l'objectif de se soigner en autonomie. L'automédication s'est développée dans les années 1970 - 1980, avant de connaître une croissance progressive sous l'impulsion des industriels du médicament, du développement et regroupement des pharmacies officinales, de la publicité grand public et de campagnes de déremboursement successives. L'automédication est un phénomène extrêmement fréquent et concerne 50 à 75 % de la population. Les risques théoriques liés à l'automédication sont nombreux, mais le risque réel semble en pratique faible. Moins de 5 % des effets indésirables médicamenteux seraient liés à l'automédication. Les classes de médicaments utilisés en automédication les plus fréquemment responsables d'effets indésirables sont les anti-inflammatoires non stéroïdiens, les antalgiques (dont le paracétamol) et les psycholeptiques. La mise en vente libre en officine des autotests va possiblement modifier les parcours d'autosoin/autoprise en charge, avec comme possibilité une médicalisation et médicamentation de domaines de la santé jusqu'à présent peu investis par les usagers en autonomie
Sediment routing and palaeogeographic evolution of the Western Alpine Foreland Basin during the early collisional stage
No full textInternational audienceIn the Western Alpine Foreland Basin (WAFB), Late Eocene and Miocene periods were characterized by longitudinal sediment routing systems: The first one was situated within the turbidite basin during the underfilled phase and exhibited a northward orientation toward the Swiss Basin, whereas the second was located in the Rhône Valley during the overfilled phase and was directed southward toward the Mediterranean Sea. The transition between these two periods occurred during the Oligocene, which corresponds to both the underfilled/ overfilled transition and the early overfilled period. In this study, we provide new fieldwork observations, seismic and well data interpretations, biostratigraphic analyses and a literature synthesis to reconstruct the palaeogeographic and source-to-sink evolution of the WAFB from Priabonian to Aquitanian. The aim is to discuss this reorganisation of sediment routing in relation to the evolution of the Alpine orogenic wedge, as well as the structural inheritance and the suite of geodynamic events that affected southeastern France during the mid-Cenozoic. We divided the WAFB sedimentary formations into four depositional sequences (S1 to S4). During the deposition of the first two sequences (Priabonian to early late Rupelian; ~37.4-28.8 Ma), the WAFB routing system was influenced by the end of the Pyrenean-Provençal orogeny, the European Cenozoic Rifting System (controlling the Rhône Valley s.l.) and the Alpine orogenic wedge (controlling the Alpine foredeep). The very first connection between the Alpine domain and the Rhône Valley is established at ~30 Ma, during the late Rupelian (S2 highstand), controlled by E-W inherited Pyrenean-Provençal structures implying a 'broken foreland'. In the meanwhile, from the Dévoluy Basin and northward, the orogenic wedge controlled a classical, although thin, foreland basin characterized by a northward sediment routing connected to the Northern Alpine Foreland Basin. Most of the S3 sequence (Latest Rupelian to middle Chattian; ~28.8-23.25 Ma) corresponds to a decrease of clastic Alpine inputs throughout SE France caused by a reorganisation of the drainage network related with the exhumation of the southern External Crystalline Massifs. S3 highstand and S4 sequence (late Chattian to Aquitanian; from ~23.25 Ma) correspond to the establishment of a longitudinal sediment routing system in the Rhône Valley, with material flowing southwards toward the Gulf of Lion, and supplied by the Palaeo-Isère to the north and potentially by the Palaeo-Durance to the south. This final stage in the reorganisation of the drainage network is clearly associated with the post-rift phase of the Gulf of Lion, which facilitated the opening of a new sink and the ultimate southward migration of the sedimentary area
Structure and speed of hydrogen–air triple flames
No full textInternational audienceTriples flames play an important role in flame stabilization processes, especially for hydrogen flames. Being able to predict the speed sT of a triple flame is crucial in many hydrogen combustor designs as it controls flame stabilization and flashback. These speeds highly depend on the mixing field between fuel and air in front of the flame, usually measured by the thickness of the profile of mixture fraction z: Δ=1/max(∂z/∂X). In the limit of high Δ values, triple flames propagate at a speed sT given by theory. When Δ decreases, sTis modified and for conventional fuels, theory indicates that it decreases.The present work focuses on the structure and speed of non-propagating H2-air triple flames when Δis varied. It uses a DNS of hydrogen–air combustion with detailed chemistry where the inlet velocity is set via a control loop ensuring that a steady triple flame is stabilized in a stream at a given value of Δ so that a (sT vs Δ) curve can be built. Results confirm that, even for hydrogen, sT can be predicted for large Δ, by the standard expression sT=(ρu/ρb)1/2sL if expansion ratio ρu/ρb and laminar burning velocity sL are evaluated at their maximum value, respectively near stoichiometry and at equivalence ratio 1.6 for H2. When Δis decreased, the triple flame speed decreases significantly but extinction is not observed.Novelty and significance statement: Few detailed studies on hydrogen triple flames exist, even though this information is of practical use for combustor design. This paper uses high-fidelity DNS to show that the theoretical expression for triple flame speeds sT=(ρu/ρb)1/2sLcan work for hydrogen flames with simple and logical adjustments. It can then be used at any pressure by experimentalists and engineers to predict stabilization of hydrogen - air diffusion flames.Moreover, this work studies triple flames stabilized in a steady mixing field, contrary to previous works focusing on the ignition and propagation of hydrogen triple flames. In these conditions, it assesses quantitatively, for the first time, how the gradient of mixture fraction decreases triple H2/air flame speeds. However, quenching is not observed. A scaling is obtained and extended to engine-relevant pressures
Domoic acid production by a Pseudo-nitzschia australis strain under zinc and copper exposure
No full textInternational audienc
Optimizing the Viability of Interacting Systems with Evolutionary Algorithms
No full textInternational audienceViability theory studies the behavior of dynamical systems, with the aim of keeping them viable, or in other terms, keep their trajectories within desired constraints in the state space. Finding strategies to keep a dynamical system viable is already a challenge for optimization algorithms, but this task becomes even harder for multi-agent systems, where agents’ individual decision can influence the dynamics of the whole system. In this paper, we consider a multi-agent dynamic system and introduce an evolutionary approach for optimizing agents’ interaction behaviour, delimited by some a priori agreements, in the form of a set of commitments, with the objective of keeping the system viable. This approach is tested on the case-study of a collective project grouping several agritouristic activities on a shared place. Experimental results show that it is possible to find a set of agents’ commitments that can maintain system viability, supporting the proposed framework’s effectiveness
Mapping the neutron flux in the cavity of the CROCUS zero-power reactor with 3 He position-sensitive detectors
No full textInternational audienceThis work presents the results of a preliminary investigation of the neutron distribution in the CROCUS zeropower reactor cavity, i.e., the internal space located between the reactor vessel and the concrete shielding, using a 3 He position-sensitive proportional counter. This detector enables the determination of the neutron interaction position along the active volume, allowing for the reconstruction of the spatial distribution of thermal neutrons. The objective of this study is to provide experimental data on the evolution, both in shape and magnitude, of the neutron flux in the surrounding region of the reactor, characterizing the spatial variations with increasing distance from the core center. Measurements are performed in two regions of the cavity: the upper part, extending from the fuel to the reactor ceiling, and the lateral side, spanning from the vessel wall to the cavity boundary
Arctic seabirds exposed to acute stress display state- and environment-dependent patterns of surface temperature change, independent of mercury contamination
No full textInternational audienc
La norme technique comme catalyseur de transfert de connaissances : la francophonie a l’œuvre dans le domaine de l’éducation
No full textOuvrage publié avec le soutien de l'Université de Bordeaux Montaigne, du Réseaux FrancophoNéa et de la Région Nouvelle AquitaineInternational audienceStandards are adopted in a wide range of fields, both technical and industrial, as well as socio-economic, cultural and linguistic. They are presented explicitly as laws and regulations, technical and industrial standards or implicitly in the form of unwritten social standards. However, in a globalization marked by a very fine mosaic of socio-cultural identities, the question arises in relation to the construction of global, transparent and coherent systems in which considerable work of consensus is necessary to ensure all types of transfers and their local adaptations. The focus here is on the global education ecosystem which develops its own standards for the transfer of knowledge and socio-cultural values through learning, teaching and training. Subcommittee 36 of the International Organization for Standardization is one of the structures of this ecosystem in which the Francophonie participates to develop international standards for distance education on the basis of universal consensus.Les normes sont adoptées dans un large éventail de domaines aussi bien techniques et industriels que socioéconomiques, culturels et linguistiques. Elles se présentent de manière explicite, telles que les lois, les règlements, les normes techniques et industrielles, ou implicites sous la forme de normes sociales non écrites. Or, dans une mondialisation marquée par une très fine mosaïque d’identités socioculturelles, la question se pose par rapport à la construction de systèmes globaux, transparents et cohérents dans lesquels un travail considérable de consensus est nécessaire pour assurer tous les types de transferts et leurs adaptations locales. La focale est mise ici sur l’écosystème mondial de l’éducation qui développe ses propres normes de transfert de connaissances et de valeurs socioculturelles par l’apprentissage, l’enseignement et la formation. Le Sous-comité 36 de l’organisation mondiale de la normalisation est l’une des structures de cet écosystème auquel participe la Francophonie pour élaborer des normes internationales de l’enseignement à distance sur la base de consensus universels