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Les perspectives d'une protection du droit à l'IVG à l'échelle de l'Union européenne (possibilité et limites d’une articulation entre protection européenne d’un droit et préservation de la démocratie)
No full textInternational audienc
Transformation and regression statistics of the size-effect method for determining fracture energy and process zone size in quasi-brittle materials
No full textInternational audienceThis paper investigates the regression statistics of the size-effect method to obtain fracture parameters of quasi-brittle materials. The correct nonlinear regression model and assumptions are established and verified using a large dataset of size-effect tests extracted from the literature. The effect of model transformation on the change in error structure is then investigated. Three different transformations are considered, including the one leading to the linear regression recommended by RILEM. The behavior of the nonlinear least squares estimators of the fracture parameters corresponding to the untransformed space, i.e., peak load P vs. specimen size D, and to each of the three transformations are discussed. Monte Carlo simulations on generated data show that the transformations lead to the violation of model assumptions and to highly skewed error distributions prone to artificial outliers. The paper also shows that the estimator corresponding to the RILEM recommendation is asymptotically biased. The estimators corresponding to the other transformations are found either asymptotically biased or do not possess the minimum variance property. Finally, simulations show that the least squares point estimates of the unknown fracture parameters differ when a model transformation is used, and that the difference is statically significant. The fitting of the fracture parameters through the size-effect method should only be obtained in the space (P vs. D) for which the nonlinear least squares estimator is asymptotically unbiased, mean square consistent, and has minimum variance. The linear regression plot suggested by RILEM should be avoided for the statistical inverse problem of the size-effect method
Combining telemetry and biologging to study the ecophysiological response of migratory to anthropogenic pressures: The coupling of telemetry and biologging, using temperature, pressure, acceleration and cardiac activity sensors, has made it possible to study the ecophysiology of salmon spawners in the Sélune basin. This approach revealed high summer mortality, complex migratory behaviour, rapid recolonisation of the areas freed up after the dams were removed, and exposure to stressful thermal conditions.
No full textThe combination of telemetry and biologging tools makes it possible to analyse the ecophysiological response of migratory fish to anthropogenic pressures such as changes in ecological continuity and climate change. Using data from the study of Atlantic salmon spawner migration in the Sélune before and after dam removal, we illustrate some possible applications of these tools for knowledge and management. From 2019 to 2023, 143 individuals were tagged at the beginning of the summer in the Sélune estuary, then monitored until reproduction in December. The results show a high mortality rate among tagged fish (between 26% and 83%) during the summer period. On average, almost a third of the tagged fish leave the Sélune for adjacent rivers. There has also been a rapid recolonisation by salmon of the newly accessible areas following the removal of the last dam in 2022. Data on temperature, acceleration, pressure and cardiac activity provide valuable information on the behaviour of individuals and their responses to the conditions they encounter. Measurements of body temperature show that summer thermal conditions in the Sélune are considered stressful for salmon according to literature standards.Le couplage d’outils de télémétrie et de biologging permet d’analyser la réponse écophysiologique des poissons migrateurs soumis aux pressions d’origine anthropiques telles que la modification de la continuité écologique et le changement climatique. En utilisant les données issues de l’étude de la migration des géniteurs de saumons atlantiques dans la Sélune avant et après arasement de barrages, nous illustrons quelques applications possibles de ces outils pour la connaissance et la gestion. De 2019 à 2023, 143 individus ont été marqués en début d’été dans l’estuaire de la Sélune, puis suivis jusqu’à la reproduction en décembre. Les résultats montrent une forte mortalité des poissons marqués (entre 26 et 83 %) pendant la période estivale. En moyenne, près d’un tiers des individus marqués quitte la Sélune pour les fleuves adjacents. On observe également une recolonisation rapide par les saumons des zones nouvellement accessibles après la suppression du dernier barrage en 2022. Les données de température, d’accélération, de pression ou d‘activité cardiaque fournissent de précieuses informations sur les comportements des individus et sur leurs réponses aux conditions qu’ils rencontrent. Les mesures des températures corporelles montrent que les conditions thermiques estivales de la Sélune sont considérées comme stressantes pour les saumons d’après les standards de la littérature
Higher rank instantons sheaves on Fano threefolds
No full textWe define instanton sheaves of higher rank on smooth Fano threefolds X of Picard rank one and show that their topological classification depends on two integers, namely the rank n (or the half of it, if the Fano index of X is odd) and the charge k.We elucidate the value of the minimal charge k0 of slope-stable n-instanton bundles (except for Fano threefolds of index 1 and genus 3 or 4), as an integer depending only on the genus of X and on n and we prove the existence of slope-stable n-instanton bundles of charge k greater than k0.Next, we study the acyclic extension of instantons on Fano threefolds with curvilinear Kuznetsov component and give a monadic description when the intermediate Jacobian is trivial.Finally, we provide several features of a general element in the main component of the moduli space of intantons, such as and generic splitting over rational curves contained in X and stable restriction to a K3 section S of X, and give applications to Lagrangian subvarieties of moduli spaces of sheaves on S
Study of the Cathode/Electrolyte Interface in an All-Sulfide-Solid-State Battery Using Lithium-Rich Transition Metal Sulfide
No full textInternational audienceAll-solid-state lithium batteries (ASSBs) are among the most promising energy storage technologies, particularly for electric vehicles, due to their enhanced safety. However, performances of these systems are still hindered by interfacial side reactions at electrode/electrolyte interfaces, especially when sulfide electrolytes are used, and additional issues of mechanical nature. In this work, an ASSB system composed of an argyrodite (Li5.7PS4.7Cl1.3) electrolyte, a lithium-rich sulfide cathode (Li1.2Ti0.8S2) operating at moderate voltage, and a lithium metal anode is investigated. The positive electrode/electrolyte interface is scrutinized during several battery cycles using X-ray photoelectron spectroscopy (XPS) via two complementary approaches (ex situ and in situ). We show that both titanium and sulfur species contribute to the electrochemical process without any detectable degradation of the electrolyte after 20 cycles and without the use of any protective coating. These results suggest that the electrochemical performances of such an all-sulfide system are not limited by the cathode/electrolyte reactivity, opening a promising route for the development of specific cathode materials adapted to sulfide electrolytes
Exploring the impact of carbon fiber surface chemistry on the structure of their alumina-silica protective coatings: A comparative study of high resistance, medium and high modulus fibers
No full textInternational audienceDue to the ease of supply, it has become usual for investigations of carbon fiber coatings to be carried out on high resistance carbon fibers, for intended applications at high temperatures in air. Yet, medium modulus and high modulus carbon fibers, for which carbon fiber coatings serves further purpose or are initially designed for, present significant variation in surface roughness and graphite plane stacking from their HR counterparts. As such, this study focuses on the transposition of the deposition of an environmental barrier coating onto HR, MM and HM carbon fibers, and further compares the coated fibers following a thermal cycle. To do so, a 20 nm bilayer thin film of amorphous alumina/alumina-silica was deposited using both atomic layer deposition (ALD) and catalytic ALD, and further annealed in inert atmosphere at 1100 °C. It was demonstrated that the HR fibers required a prior annealing to outgas the fiber core, while residual elements in the surface region of HR and HM fibers impeded the integrity of the film. Furthermore, the density of grooves at the carbon fiber surface was shown to hold substantial impact on the kinetics of crystallisation of the thin films, being determinant to the fiber surface O/C atom ratio
L’instrumentalisation de la jurisprudence constitutionnelle à des fins de légitimation d’une Constitution populiste. Les exemples de la Hongrie et de la France
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Néoruralité catastrophiste, littérature post-apocalyptique et imaginaire de l’effondrement
No full textInternational audienceSome similar eschatological themes can be found both in the discourses and practices of catastrophist neorurals and in a number of francophone post-apocalyptic literary works, four of which are studied in this article for their similarities in their imaginary: Ravage (Barjavel 1943), Malevil (Merle 1972), Le feu de Dieu (Bordage 2009) and Et toujours les forêts (Colette 2020). Anticipations of the collapse of the industrial society – as well founded as they may be in a world of ecological dereliction, and without directly commenting on their political relevance – are told through aesthetic canons that derive from a certain cultural imaginary. Where American post-apocalyptic narratives, for example, draw heavily on the imagination of the West, the French theme re-enacts the opposition between Paris (an archetype of urban concentration and power) and the enclosed countryside, which is both a natural refuge and a nostalgic link with an agrarian past identified with the narrator’s childhood. Certain themes of the agrarian movement (which had a strong foothold in rural France in the last century) and its regionalist epigones can inform a national imaginary, particularly in the retreat towards a patriarchal family conservatism opposed to cultural decadence. It is crucial, then, to examine the political significance of such an eschatological imaginary if we want to avoid ecological lifestyles appearing to run counter to the ideals of emancipation
Loi n° 2005-102 du 11 mars 2005 pour l'égalité des droits et des chances, la participation et la citoyenneté des personnes handicapées : un bilan contrasté
No full textThe twentieth anniversary of the Act of 11 February 2010 provides an opportunity to take stock of its application and identify possible courses of action to strengthen the effectiveness of the rights of people with disabilities under the UN Convention on the Rights of Persons with Disabilities.Le vingtième anniversaire de la loi du 11 février 2010 cinq procure l'occasion de procéder à un bilan de son application et d'identifier des perspectives d'action de nature à renforcer l'effectivité des droits des personnes en situation de handicap au regard de la Convention internationale des droits des personnes handicapées de l'ONU