Journal of Next-Generation Research 5.0
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Les adaptations de programmes en Histoire-Géographie à La Réunion : reconnaissance de l’altérité et questionnement identitaire dans les pratiques enseignantes
No full textInternational audienc
Aspects chronogénétiques de l'étude de la langue : variations d'analyse de la langue et variables didactiques
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Gravity darkening in late-type stars. I. The Coriolis effect
No full textInternational audienceContext. Recent interferometric data have been used to constrain the brightness distribution at the surface of nearby stars, in particular the so-called gravity darkening that makes fast rotating stars brighter at their poles than at their equator. However, good models of gravity darkening are missing for stars that posses a convective envelope.Aims. In order to better understand how rotation affects the heat transfer in stellar convective envelopes, we focus on the heat flux distribution in latitude at the outer surface of numerical models.Methods. We carry out a systematic parameter study of three-dimensional, direct numerical simulations of anelastic convection in rotating spherical shells. As a first step, we neglect the centrifugal acceleration and retain only the Coriolis force. The fluid instability is driven by a fixed entropy drop between the inner and outer boundaries where stress-free boundary conditions are applied for the velocity field. Restricting our investigations to hydrodynamical models with a thermal Prandtl number fixed to unity, we consider both thick and thin (solar-like) shells, and vary the stratification over three orders of magnitude. We measure the heat transfer efficiency in terms of the Nusselt number, defined as the output luminosity normalised by the conductive state luminosity.Results. We report diverse Nusselt number profiles in latitude, ranging from brighter (usually at the onset of convection) to darker equator and uniform profiles. We find that the variations of the surface brightness are mainly controlled by the surface value of the local Rossby number: when the Coriolis force dominates the dynamics, the heat flux is weakened in the equatorial region by the zonal wind and enhanced at the poles by convective motions inside the tangent cylinder. In the presence of a strong background density stratification however, as expected in real stars, the increase of the local Rossby number in the outer layers leads to uniformisation of the surface heat flux distribution
Towards Context & Climate Sensitive Urban Design An integrated simulation and parametric design approach
No full textInternational audienceTo implement the concept of integrated design, an urban modelling, simulation and design platform was developed. It embeds a design framework built upon the strengths of parametric modelling and existing building performance simulation tools. The centralisation of the synthesis, analysis, evaluation and optimisation activities in a single interface helps to support the integrated design concept. Data exchange and treatment allow informing both the simulation tools and the design process in terms of context and climate consideration
A SAS macro to estimate Average Treatment Effects with Matching Estimators
No full textThis paper presents a SAS macro to estimate the Average Treatment Effect (ATE) and the Average Treatment Effect for the Treated (ATET) with nearest-neighbor matching
A 100-m.y.-long window onto mass-flow processes in the Patagonian Mesozoic subduction zone (Diego de Almagro Island, Chile)
No full textDiego de Almagro Island was formed by the subduction and accretion of several seafloor-derived tectonic slices with very heterogeneous ages and pressure-temperature-time (P-T-t) paths. The highest element of the pile (the Lazaro unit) evidences subduction in the high-P granulite field (∼1.3 GPa, 750 °C) at ca. 163 Ma. Below it, a thin tectonic sliver (the Garnet Amphibolite unit) preserves eclogite-facies remnants (∼570 °C and ∼1.7 GPa) formed at ca. 131 Ma (in situ U-Pb zircon rim ages). Peak assemblages were nearly fully amphibolitized during decompression down to ∼1.2 GPa and ∼600 °C at 125–120 Ma (Rb-Sr multimineral dating). The underlying Blueschist unit has ∼50 m.y. younger metamorphic ages and exhibits slightly cooler peak burial conditions (∼520 °C, 1.7 GPa; ca. 80 Ma, in situ white mica Ar-Ar ages and multimineral Rb-Sr dating) and is devoid of amphibolitization. The mylonites from the sinistral strike-slip Seno Arcabuz shear zone bounding Diego de Almagro Island to the east also exhibit amphibolite-facies (∼620 °C and ∼0.9 GPa) deformation at ca. 117 Ma (multimineral Rb-Sr ages). In situ white mica Ar-Ar dating and multimineral Rb-Sr dating of low-T mylonites (∼450 °C) along the base of the Lazaro unit reveal partial resetting of high-T assemblages during tectonic displacement between 115 and 72 Ma and exhumation of the slice stack.Detrital zircon U-Th-Pb ages indicate that the material accreted on Diego de Almagro Island has been mostly recycled from a Permian–Triassic accretionary wedge (Madre de Dios accretionary complex) exposed along the subduction buttress. Geological and geochronological constraints suggest that the rocks of the Seno Arcabuz shear zone and the Lazaro unit were tectonically eroded from the buttress, while the underlying Garnet Amphibolite and Blueschist units instead derive from the subducted oceanic basin, with increasingly younger maximum depositional ages. The very long residence time of the rocks (∼90 m.y. for the Lazaro unit) along the hanging wall of the subduction interface recorded long-term cooling along the Patagonian subduction zone during the Mesozoic. Diego de Almagro Island therefore represents a unique window onto long-term tectonic processes such as subduction interface down-stepping, tectonic erosion, and episodic underplating near the base of an accretionary wedge (40–50 km)
Etude des effets de la glycation sur les interactions protéine-ligand dans le cadre du diabète et de l’athérosclérose : la liaison entre l’albumine et le liraglutide et entre l’apolipoprotéine A1 et ses partenaires de liaison
No full textProtein-ligand interactions are involved in many biochemical processes. They are notably implicated in the role of transporter proteins in blood. Albumin, the most abundant plasma protein, and apolipoprotein A1 (ApoA1), which is the main component of high-density lipoprotein (HDL) belong to this class of proteins. In the context of diabetes, proteins are altered by glycation which leads to structural modifications and potentially affect their interactions.The first objective of this work was to determine the impact of albumin glycation on its binding to liraglutide, a drug increasingly used in the treatment of type 2 diabetes. Then, the second part of this work involved the production of recombinant functional human ApoA1 in order to study its interaction properties, in its lipid-free form or associated with phospholipids. The NMR (nuclear magnetic resonance) technique has been used on proteins previously labeled with fluorine (for liraglutide) or stable 13C/15N isotopes (for ApoA1). In addition, isothermal titration microcalorimetry (ITC), has been applied to the study of interactions with the advantage of not requiring any labeling. Various cloning strategies have been explored for the overexpression of ApoA1 in Clearcoli bacteria.The results demonstrate an alteration of the affinity of albumin for liraglutide in vitro and in vivo, depending on the degree of glycation. These results, supported by a lipidomic and peptide analysis, explain clinical observations concerning the decrease of efficacy of albumin-binding drugs in patients with poorly controlled diabetes. Regarding ApoA1, the choice of the fusion tag remains to be optimized, but both labeled and unlabeled ApoA1 were successfully overexpressed at high yields in a soluble form.Les interactions protéine-ligand interviennent dans de nombreux processus biochimiques et permettent notamment à certaines protéines sanguines d’assurer leur rôle de transport. Parmi ces protéines figurent notamment l’albumine, protéine la plus abondante du plasma, ou l’apolipoprotéine A1 (ApoA1), majoritaire au sein des lipoprotéines de haute densité (HDL). Dans un contexte diabétique, la glycation des protéines induit des modifications structurales affectant ainsi leur potentiel d’interaction.Le premier objectif de ce travail de thèse visait à déterminer l’impact de la glycation de l’albumine sur sa liaison au liraglutide, un médicament de plus en plus utilisé dans le traitement du diabète de type 2. Ensuite, la seconde partie de ce travail a consisté en la production d’une ApoA1 humaine recombinante fonctionnelle afin d’étudier ses propriétés d’interaction, sous forme libre ou associée aux phospholipides. La technique RMN (résonance magnétique nucléaire) a été utilisée sur les protéines préalablement marquées au fluor (pour le liraglutide) ou aux isotopes stables 13C/15N (pour l’ApoA1). La titration microcalorimétrique isotherme (ITC), méthode complémentaire à la RMN a été appliquée pour l’étude des interactions avec l’avantage de ne nécessiter aucun marquage. Différentes stratégies de clonage ont été explorées pour la surexpression de l’ApoA1 en bactérie Clearcoli.Les résultats obtenus démontrent une altération de l’affinité de l’albumine pour le liraglutide in vitro et in vivo, dépendante du degré de glycation. Ces résultats, enrichis d’une analyse lipidomique et peptidique, permettent d’expliquer les observations cliniques concernant la baisse de l’efficacité de médicaments liant l’albumine chez les patients ayant un diabète mal contrôlé. Concernant l’ApoA1, le choix de l’étiquette de fusion reste à optimiser, mais sa surexpression de manière soluble et abondante a été obtenue pour l’ApoA1 marquée et non marquée
Le tourisme dans les petites économies insulaires : analyse des fondamentaux de la spécialisation touristique comme source soutenable de croissance
No full textTourism has become a social, cultural and economic phenomenon. However, the impact of tourism on a long-term economy growth remains ambiguous, especially for small island economies (SIE).This thesis seeks to identify the fundamentals of tourism specialization as a sustainable source of growth for a SIE. On the one hand, it has led us to redefine the main components of tourism as a social and economic activity and to clarify how tourism contributes to the economic growth. On the other hand, this thesis reveals the ambiguity of the relationship between tourism and growth. It provides new explanations for a more virtuous tourism growth model and more adapted to the global tourism market.The results of the introduction of tourism into a Romer's model of endogenous growth and those of a threshold regression model applied to a sample of SEI call into question the hypothesis of linearity between tourist specialization and economic growth. The thesis demonstrates the end of a model of intensive tourist development. It concludes that tourism is a sustainable source of growth for an SIE, when intelligence and agility constitute the leitmotif of a sustainable, multi-stakeholder tourism strategy.Phénomène social, culturel mais aussi économique, le tourisme s'est imposé au fil des décennies comme une source de revenus et de devises étrangères pour les pays hôtes au cours du 20e siècle. Cependant, l'impact du tourisme sur une économie à long terme et notamment une petite économie insulaire (PEI) reste encore ambigu.Cette thèse cherche à poser clairement la question de l’analyse des fondamentaux de la spécialisation touristique comme source soutenable de croissance pour une petite économie insulaire. Cette entreprise, réalisée en deux parties, nous conduit, d'une part, à redéfinir les principaux composants du tourisme en tant qu'activité sociale et économique, et à préciser comment le tourisme contribue à la croissance économique d’une PEI. D'autre part, la thèse lève le voile sur l'ambigüité de la relation entre tourisme et croissance. Elle fournit de nouveaux éléments d'explication d'un modèle de croissance par le tourisme plus vertueux et adapté au marché du tourisme mondial. Les résultats de l'introduction du tourisme dans un modèle théorique de croissance endogène à la Romer et d'une formalisation économétrique à seuil appliquée à un échantillon de PEI à l'aide de l'indice de pénétration touristique remettent en cause l'hypothèse de linéarité entre spécialisation touristique et croissance économique. Ils démontrent la fin d'un modèle de développement touristique intensif. Toutefois, cette situation n'est pas une fatalité. Notre analyse aboutit à la conclusion que le tourisme constitue une source soutenable de croissance pour une économie d'une PEI, lorsque l'intelligence et l'agilité forment les leitmotivs d'une stratégie touristique durable et multipartite
Structure of Strontium Aluminosilicate Glasses from Molecular Dynamics Simulations, Neutron Diffraction and Nuclear Magnetic Resonance Studies
No full textInternational audienceThe structure of strontium glasses with composition (SiO (Al O(SrO) (R=[SrO]/[AlO ]=1) and (SiO)(AlO)(SrO) (R=3) have been explored experimentally over both short and intermediate length scales using neutron diffraction, Al and Si nuclear magnetic resonance and classical molecular dynamics simulations in model systems containing around 10000 atoms. We aim at understanding the structural role of aluminum and strontium as a function of the chemical composition of these glasses. Short-and medium-range structure such as aluminum coordination, bond angle distribution, Q distribution and oxygen speciation have been systematically studied. Two potential forms of the repulsive short-range interactions have been investigated, namely the Buckingham and Morse forms. The comparison allows us to derive general trends independent of the particular choice of the potential form. In both cases, it is found that aluminum ions are mainly four-fold coordinated and mix with the silicon network favoring Al/Si mixing in terms of Al-O-Si linkages. For the R = 1 glass series, despite the full charge compensation ([SrO]=[Al ]), a small fraction of five-fold aluminum is observed both experimentally and in MD simulations, while the concentration of six-fold aluminum is negligible. MD shows that 2 five-fold aluminum units AlO preferentially adopt small rings configuration and link to tricoordinated oxygen atoms which population increases with the aluminum content and are mainly found in OAl and OAlSi configurations. The modeled Sr speciation mainly involves SrO and SrO polyhedra, giving a range of average Sr coordination numbers between 7 and 8 slightly dependent on the short-range repulsive potential form. A detailed statistical analysis of the T-O-T' (T,T'=Al,Si), accounting for the population of the various oxygen speciation, reveals that both potentials predicts a nearly identical Al/Si mixing
POUR INTRODUIRE À LA PRAGMATIQUE
No full textInternational audienceThe attitude adopted here is far away the erudition of a RECANATI or a SEARLE. It aims the simplicity and at the same time the exhaustivity in putting in the core of speech act the narrativity understood as a state transformation. In this way, some difficulties are avoided, notably, the idea of perlocutionary force which couldn't involve the linguistic and, even less the least the pragmatic. At the same time, we attest that in the language there is no more than language, the referent is an artefact, thus, the claim of reflexivity in pragmatic is honored and, at the same time, the absence of performative verb shouldn't be taken as an argument of the failure of the illocutionary force which is predicted by the extension of the performativity at all statements.L'attitude adoptée ici est loin de l'érudition d'un RECANATI ou d'un SEARLE. Elle vise la simplicité et à la fois l'exhaustivité en mettant au coeur de la théorie des actes de langage la narrativité comprise comme une transformation d'état. De cette manière, certaines apories sont évitées, notamment, l'idée de force perlocutoire qui ne saurait concerner nullement la linguistique et encore moins la pragmatique. Du coup, nous attestons que dans le langage, il n'y a que du langage, le référent n'est qu'un artefact, ainsi, la revendication de la réflexivité en pragmatique est honorée en même temps que l'absence d'un verbe performatif ne saurait plus être tenue comme argument de faillite de la force illocutoire que prévoit la généralisation de la performativité à tous les énoncés