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Les Fées ou les Contes de ma mère l'Oye de Dufresny et Brugière de Barante
No full textInternational audienceUn mois après avoir donné "Pasquin et Marforio, médecin des mœurs" (3 février 1697) à la Comédie-Italienne, Dufresny et Brugière de Barante collaborent une seconde fois et créent "Les Fées ou les Contes de ma mère l’Oye" le 2 mars 1697. Cette pièce conclut le sixième et dernier tome du "Théâtre italien" de Gherardi imprimé en 1700 chez Cusson et Witte. Avec "Les Fées", Dufresny et Brugière de Barante se tournent vers l’univers de la féerie à la mode à la fin du XVIIe siècle. Reprenant des personnages, des objets et des situations caractéristiques du conte, "Les Fées" s’inscrit dans la mouvance du merveilleux tout particulièrement illustrée par Perrault et Madame d’Aulnoy. Le traitement des deux jeunes amoureux, qui valorise davantage la princesse (Isménie) que son prétendant (Octave), témoigne chez Dufresny et Brugière de Barante d’une connaissance des habitudes des dramaturges tragiques, et fait signe vers une œuvre lyrique créée à peine deux mois auparavant : "Méduse" (13 janvier 1697) de l’abbé Boyer, sur une musique de Gervais. Enfin, on observe dans "Les Fées" une intégration de la satire sociale (tendance courante chez les contributeurs du Théâtre-Italien en ces années 1690) alors que l’univers féerique ne s’y prête guère a priori. La fête, pourrait-on dire, ne s'en trouve pas gâchée : "Les Fées" convie le public à un spectacle de l’enchantement (orchestré par le magicien Arlequin) qui exploite les ressources techniques de la Comédie-Italienne, mais aussi la polyvalence du jeu des acteurs. Cet esprit de fantaisie, indifférent aux "moralités" délivrées dans les contes, vise à célébrer le plaisir de conter et de jouer – les deux se confondant chez les Italiens
Back home : ten years on, a fresh look at the Quéven beaker house (Morbihan)
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Rapport de conjoncture 2024 de la Commission Interdisciplinaire (CID) 52 Environnement & Société : du Savoir à l'Action du Comité National de la Recherche Scientifique du CNRS
No full textThe environmental and societal challenges posed by climate change and the erosion of biodiversity raise the crucial question of our planet's short-term habitability. CID 52 Environments & Society : from knowledge to action develops a collective, interdisciplinary and concerted scientific approach to meet this challenge, by seeking innovative, inclusive methodologies and solutions that respect socio-ecosystems. Given the urgency of the situation, the commission stresses the need for scientists, decision-makers and citizens to work together to produce useful, transformative solutions for adapting societies to global change. These solutions explore social and technological change, as well as nature-based approaches. The report also highlights the importance of sustainable evaluation of solutions, while promoting interdisciplinarity as a response to global crises. CID 52 proposes to rename the commission Socio-ecosystems and the global environmental crisis: issues, knowledge and methodologies for sustainable solutions, better reflecting the integration of this research into public policy for effective and sustainable assimilation and adaptation of human and non-human populations.Les défis environnementaux et sociétaux associés au dérèglement climatique et à l'érosion de la biodiversité posent la question cruciale de l'habitabilité de notre planète à court terme. La CID 52 Environnements Sociétés : du savoir à l'action développe une approche scientifique collective, interdisciplinaire et concertée pour répondre à cet enjeu, en cherchant des méthodologies et des solutions innovantes, inclusives et respectueuses des socio-écosystèmes. Face à l'urgence de la situation, la commission insiste sur les nécessaires collaborations entre scientifiques, décideurs et citoyens pour coproduire des solutions utiles et transformantes d'adaptation des sociétés aux changements globaux. Ces solutions explorent ainsi les changements sociaux, technologiques et des approches fondées sur la nature. Le rapport met aussi en avant l'importance d'une évaluation durable des solutions, tout en promouvant l'interdisciplinarité pour répondre aux crises globales. La CID 52 propose de renommer la commission Socioécosystèmes et crise environnementale globale : enjeux, savoirs et méthodologies pour des solutions durables, reflétant mieux l'intégration de ces recherches dans les politiques publiques pour une assimilation et une adaptation efficace et durable des populations humaines et non-humaines.</div
Generation of a compound heterozygous ABCA4 rat model with pathological features of STGD1
No full textInternational audienceThe ABCA4 protein plays an essential role in mammalian vision, ensuring the correct localization of all-trans-retinal within the visual cycle. Mutations in the ABCA4 gene are responsible for the juvenile maculopathy, Stargardt disease (STGD1). We investigated the most common variant underlying STGD1 phenotype in a rat model carrying the ortholog to the human c.5882G > A/p.(Gly1961Glu) (G1961E) in ABCA4. While the pathogenicity of this variant has recently been questioned, we examine here whether the ortholog rat variant is associated with vitamin A toxicity in the retina. By crossing the rat line with a rat line deficient in ABCA4 protein, we reveal a more pathogenic phenotype in line with compound heterozygosity, making the model suitable for testing of gene, cell and pharmacological therapies
Microwave Scattering from Sea Surfaces: CBFM Hybridized to Kirchhoff and Weak-coupling Approximations and to Identical Block PBFs
No full textInternational audienceIn this paper, the characteristic basis function method (CBFM) is accelerated to calculate the monostatic and bistatic normalized radar cross sections from one-dimensional highly-conducting sea surfaces in the microwave bands (C and Ku). In the framework of the two-scale asymptotic model, the subsurface length of the block is judiciously derived to contain all the surface curvature components (small scale) and the associated PBFs, assumed to be identical for all blocks, are rapidly calculated from the Kirchhoff approximation. In addition, the reduced matrix calculation is accelerated by neglecting the interactions between far blocks and by introducing a roughness slight approximation (matrix-matrix products can be done from fast Fourier transforms), which also allows us to expedite the resolution of the linear system since the matrix is sparse. Numerical results show the efficiency of CBFM-KA
Tailored Synthesis of Conformal Si‐Al Coatings on TiO2 Nanotubes for Hybrid Negative Electrodes of Lithium‐Ion Batteries
No full textInternational audienceAn original synthesis route has been developed to optimize silicon's utility in replacing graphite as anode material in Li‐ion batteries. This involves blending silicon with aluminium to enhance its conductivity. The silicon‐aluminium is co‐deposited on a nanoporous titanium dioxide nanotube matrix, which serves as an active current collector, thereby eliminating the need for inactive binders and ensuring robust mechanical stability during cycling. The nanostructured negative electrode is fabricated through two electrochemical synthesis steps: first, the anodization of a titanium foil, followed by the co‐electrodeposition of silicon and aluminium using a room temperature ionic liquid electrolyte. This co‐electrodeposition enables the in‐situ integration of aluminium into the silicon deposit. The resulting Si‐Al/TiO2 nanotube nanocomposite anode exhibits improved cyclic stability and enhanced rate capability. The observed enhancement in battery electrochemical performance underscores the significance of this electrochemical process in fabricating such nanostructured silicon negative composite electrodes
ASSESSMENT OF TURBULENCE MODELS USING AUTOMATIC GRID REFINEMENT FOR THE WINDSOR BODY AT YAW
No full textInternational audienceIn this paper, the influence of turbulence modelling on flow prediction around a simplified square-back model, the Windsor body, is investigated. Three turbulence models are used: the kω SST, and the hybrid RANS/LES models DDES-SST (Delayed Detached Eddy Simulation) and IDDES-SST (Improved Delayed Detached Eddy Simulation), which are based on the kω model. Numerical simulations are performed using the ISIS-CFD code to predict the flow around the Windsor body, which was one of the test cases in the Automotive CFD Prediction Workshop. Two types of mesh are used: those generated by the AutoCFD Workshop organisers and those obtained with automatic mesh refinement, which are then adapted to the flow. The numerical simulations show that mesh convergence for results obtained with adapted meshes is much faster than that for results obtained with meshes generated by the workshop organisers. The results obtained with the RANS/LES hybrid models are in better agreement with experimental results than those obtained with the kω SST model. The results obtained with the IDDES-SST model are slightly better than those obtained with the DDES-SST model, regardless of the mesh type. Furthermore, the results obtained with a turbulence model and an adapted mesh are in better agreement with experimental measurements than those obtained with the meshes from the Workshop organisers. Consequently, mesh refinement and the hybrid RANS/LES IDDES-SST model are the solution for this type of flow.</div
Conversation-Based Multimodal Abuse Detection Through Text and Graph Embeddings
No full textInternational audienceAbusive behavior is common on online social networks, and forces the hosts of such platforms to find new solutions to address this problem. Various methods have been proposed to automate this task in the past decade. Most of them rely on the exchanged content, but ignore the structure and dynamics of the conversation, which could provide some relevant information. In this article, we propose to use representation learning methods to automatically produce embeddings of this textual content and of the conversational graphs depicting message exchanges. While the latter could be enhanced by including additional information on top of the raw conversational structure, no method currently exists to learn whole-graph representations using simultaneously edge directions, weights, signs, and vertex attributes. We propose two such methods to fill this gap in the literature. We experiment with 5 textual and 13 graph embedding methods, and apply them to a dataset of online messages annotated for abuse detection. Our best results achieve an F -measure of 81.02 using text alone and 80.61 using graphs alone. We also combine both modalities of information (text and graphs) through three fusion strategies, and show that this strongly improves abuse detection performance, increasing the F -measure to 87.06. Finally, we identify which specific engineered features are captured by the embedding methods under consideration. These features have clear interpretations and help explain what information the representation learning methods deem discriminative
Analyse spatio-temporelle des éboulements/écroulements (2000-2015) entre Etretat et Le Tréport (Seine-Maritime, Normandie) avec une régression logistique binomiale spatiale orientée de panel
No full textNational audienceThe cliffs of Seine-Maritime are retreating at a rate of more than one decimetre per year. However, this annual average hides the non-linear nature of erosion in space and time: there are long periods of inactivity interspersed with sudden and localised rockfalls. Understanding the spatio-temporal distribution of these mass movements represents a significant scientific and management challenge. Our hypothesis is that these rockfalls spread in time and space according to previous falls upstream of the littoral drift. To verify this, our data is based on 490 rockfalls recorded between Etretat and Le Tréport (90 km) on IGN (National Geographic Institute) orthophotographs between 2000 and 2015. Using spatial regressions, we studied the presence or absence of falls at a given date and location, based on quantitative variables measured at earlier dates (presence or absence of previous rockfalls, rockfall deposit area, and evacuation duration). A spatial logistic regression was created to analyse the propagation of falls, incorporating the direction of the littoral drift through an oriented neighbourhood matrix. Our results demonstrated that the distribution of rockfalls in 2015 was 11 % (R²) explained by the characteristics of previous mass movements, with an influence zone up to 600 m downdrift. These results are consistent with previous naturalistic studies that placed this influence around 400 m and up to 700 m. Furthermore, the contribution of the previous rockfalls decreases sharply with time, and the larger the previous rockfalls, the greater the probability of mass movement occurrence downdrift.Les falaises de Seine-Maritime reculent à une vitesse moyenne supérieure à un décimètre par an. Cependant, cette valeur masque le caractère irrégulier de l'érosion dans le temps et dans l’espace : de longues périodes sans activité gravitaire sont interrompues par un éboulement/écroulement, par définition soudain et localisé. Comprendre la distribution spatio-temporelle de ces phénomènes reste un défi scientifique et de gestion. Notre hypothèse est que ces éboulements/écroulements se diffusent dans le temps et dans l’espace en fonction de ceux ayant eu lieu précédemment en amont de la dérive littorale. Pour la vérifier, nos données s’appuient sur 490 éboulements/écroulements recensés entre Etretat et Le Tréport (90 km) sur les orthophotographies IGN entre 2000 et 2015. Grâce à des régressions spatiales, nous avons étudié la présence ou l'absence d’éboulements/écroulements à une date et un lieu donnés, en fonction de variables quantitatives mesurées à des dates antérieures (présence ou absence d’éboulements/écroulements précédents, aire éboulée/écroulée, durée d’évacuation). Nous avons créé une régression logistique spatiale pour analyser cette diffusion, intégrant la direction de la dérive littorale via une matrice de voisinage orientée. Nos résultats montrent que la distribution des éboulements/écroulements en 2015 est expliquée à 11 % (R²) par les caractéristiques de ceux précédents, avec une zone d’influence jusqu’à 600 m en aval-dérive. Ces résultats concordent avec la littérature scientifique situant cette influence entre 400 et 700 m. Par ailleurs, la contribution des éboulements/écroulements précédents diminue rapidement avec le temps, et plus ils sont volumineux, plus cela augmentera la probabilité d’occurrence d’un éboulement/écroulement en aval-dérive
Modeling, analysis and design of an extensible planar parallel tendon actuated continuum robot
No full textInternational audienceIn this paper, we introduce a novel design for a compressible/extensible planar continuum parallel manipulator, characterized by fixed joints and tendon-based actuation with parallel routing. The goal of this design is to generate a planar workspace without adding any rigid translational actuators by considering compressible legs. To optimize the robot's design, its static behavior is first modeled using a Jacobian-based geometric variable strain approach, providing a foundation for performance analysis. We then explore key performance metrics, including workspace, stability, and payload capacity, in relation to critical design parameters: the distance between the robot's legs and the bending-to-compression stiffness ratio. While the leg distance is a well-studied factor in parallel architectures, the influence of the stiffness ratio, despite its significant impact on performance, has received limited attention. Our work investigates the effects of these parameters, culminating in the development of a new modular prototype that leverages these insights to obtain optimal robot performances.</div