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La justification orthographique de professeurs des écoles en formation initiale : ce que nous apprend l'analyse de quelques séances de classe
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Droit "rural" et sciences sociales: nourrir les échanges
No full textInternational audienceConférence plénière prononcée à l'Assemblée générale du département ECOSOCIO d'INRAE le 6 novembre 2025. Cette présentation analyse les rapports entre les sciences juridiques et les autres sciences sociales (économie, sociologie, gestion) et sur la manière dont les chercheurs de ces disciplines peuvent mieux collaborer
VIVALDy: A Hybrid Generative Reduced-Order Model for Turbulent Flows, Applied to Vortex-Induced Vibrations
No full textDeveloping reduced-order models applicable to fluid-dynamics problems involving complex geometries and different flow conditions remains a critical challenge for turbulent flows. This study introduces VIVALDy, a novel machine-learning framework that employs a hybrid -Variational Autoencoder-Generative Adversarial Network (-VAE-GAN) architecture with masked convolutions to extract dominant flow features into a compact latent space while preserving fidelity at solid-fluid interfaces. A bidirectional transformer then models the temporal evolution of these features, learning to predict flow trajectories from minimal sensor inputs. This two-stage approach enables the transformer to map sensor measurements to dominant flow variables identified by the autoencoder, advancing reduced-order modeling capabilities for real-time flow prediction. The effectiveness of the framework is demonstrated through application to a problem relevant to vortex-induced vibration (VIV) energy harvesting systems, reconstructing the turbulent flow around a one-degree-of-freedom moving cylinder. Validated against experimental data spanning fluid-structure interaction regimes of interest, VIVALDy accurately predicts different flow states using only the cylinder displacement. The framework demonstrates adequate performance in both reconstruction accuracy and statistical fidelity across diverse operating conditions, enabling efficient prediction of the turbulent flow phenomena governing vortex-induced vibration
Diversity and spread of cytoplasmic incompatibility genes among maternally inherited symbionts
No full textInternational audienceCytoplasmic Incompatibility (CI) causes embryonic lethality in arthropods, resulting in a significant reduction in reproductive success. In most cases, this reproductive failure is driven by Wolbachia endosymbionts through their cifA-cifB gene pair, whose products disrupts arthropod DNA replication during embryogenesis. While a cif pair has been considered a hallmark of Wolbachia , its presence and functional significance in other bacterial lineages remains poorly investigated. Here, we conducted a comprehensive survey of 762 genomes spanning non-Wolbachia endosymbionts and their close relatives, revealing that the cif pair is far more widespread than previously recognized. We identified cif loci in 8.4% of the surveyed genomes, with a striking incidence of 17.4% in facultative symbionts. Beyond Wolbachia, cif pair occurs across eight bacterial genera spanning α-Proteobacteria, γ-Proteobacteria, Mollicutes, and Bacteroidota. Notably, cif pair has been identified in several intracellular pathogens of mammals showing high rate of transovarial transmission in their arthropod hosts, suggesting a potential role of cif pair and CI in vector-borne disease dynamics. Structural analyses further reveal that the PD(D/E)-XK nucleases and AAA-ATPase-like motifs are consistently conserved across cif pairs in all bacterial taxa. Moreover, cif pairs are frequently integrated within diverse mobile genetic elements, from transposons to large intact WO prophages in Wolbachia and RAGEs in Rickettsiaceae. Phylogenetic analyses reveal recent and potentially ongoing horizontal transfers of cif pair between distantly related bacterial lineages, a process potentially facilitated by mobile genetic elements. Indeed, the PDDEXK2 transposase exhibits a phylogenetic pattern consistent with the co-transmission of cif genes, suggesting that it may facilitate horizontal transfers of cif across bacterial lineages. Furthermore, the detection of endosymbionts harboring cif pair in arthropod groups where Wolbachia is scarce, such as ticks, suggests that CI may be more widespread than previously known, with significant implications for arthropod symbiosis, reproductive manipulation, and future biocontrol strategies
High-fidelity CFD Simulation of a Turbulent Mixed Convection Axial Flow in a Heated Rod Bundle Using code_saturne
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X-Ray Diffraction Reveals the Consequences of Strong Deformation in Thin Smectic Films: Dilation and Chevron Formation
No full textInternational audienceSmectic liquid crystals can be viewed as model systems for lamellar structures for which there has been extensive theoretical development. We demonstrate that a nonlinear energy description is required with respect to the usual Landau-de Gennes elasticity in order to explain the observed layer spacing of highly curved smectic layers. Using x-ray diffraction we have quantitatively determined the dilation of bent layers distorted by antagonistic anchoring (as high as 1.8% of dilation for the most bent smectic layers) and accurately described it by the minimal nonlinear expression for energy. We observe a 1°tilt of planar layers that are connected to the curved layers. This value is consistent with simple energetic calculations, demonstrating how the bending energy impacts the overall structure of a thin distorted smectic film. Finally, we show that combined x-ray measurements and theoretical modeling allow for the quantitative determination of the number of curved smectic layers and of the resulting thickness of the dilated region with unprecedented precision
Entre ténèbres et clairvoyance, la nuit dans la <i>Estoria de España</i>
No full textInternational audienceDans la Estoria de España, la nuit n'est pas un élément central, loin de là, elle apparaît à la marge, accompagnant tel ou tel épisode. Simple situation d'énonciation, comme l'on préciserait que le soleil brille ou que les oiseaux chantent ? Simple marqueur temporel comme pour marquer les étapes d'un voyage ou la durée d'une bataille ? C'est effectivement le cas pour nombre d'occurrences. Néanmoins, dans certains cas, certes peu nombreux au regard de tous les épisodes diurnes, les rédacteurs jugent utile de planter un décor nocturne. Dès lors, les cas où les nuits méritent d'être décrites deviennent pertinents et peuvent être considérés comme significatifs, précisément en raison de leur rareté
<i>On the Typology of Liturgical Books from the Western Middle Ages. Zur Typologie liturgischer Bücher des westlichen Mittelalters</i>, Andrew J. M. Irving et Harald Buchinger (dir.)
No full textInternational audienceLe présent volume est issu d'une rencontre scientifique organisée en juin 2016 à l'université de Ratisbonne, là où, depuis quelques années, sous la houlette de l'un des éditeurs du livre – Harald Buchinger –, se tiennent régulièrement d'importants colloques consacrés à la liturgie médiévale et à ses sources. [On the Typology of Liturgical Books from the Western Middle Ages. Zur Typologie liturgischer Bücher des westlichen Mittelalters, Andrew J. M. Irving et Harald Buchinger (dir.), , Münster, Aschendorff (Liturgiewissenschaftliche Quellen und Forschungen, 115), 2023, 658 p.
Intersubjective strategies in a corpus of French esports team communication
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Existe-il un droit de la chevalerie, ou: la littérature servirait -elle à l'enseignement de la coutume? Enquête dans le Tristan en Prose
No full textInternational audienceLe but de cette conférence est d'examiner l'existence d'un droit coutumier littéraire dans un grand roman du treizième siècle, le Tristan en Prose. Elle examine les conditions de la coutume -savoir normatif collectif- hors de la guerre et des duels judiciaires