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Livre de la Nature, Nature du livre : Pratiques des femmes botanistes
No full textInternational audienc
Les savoirs agroécologiques, un enjeu de luttes dans l’enseignement agricole
No full textInternational audienceCe chapitre examine les tensions dans l'enseignement agricole français concernant la transmission des savoirs agroécologiques. Il met en lumière l'influence du syndicalisme agricole dominant, notamment la FNSEA, sur la définition institutionnelle de la transition agroécologique. Cette définition, suffisamment large, permet de promouvoir l'agriculture raisonnée et de précision, sans remettre en cause les logiques productivistes. Le texte souligne la marginalisation historique de l'agriculture biologique dans les formations agricoles initiales, puis son inclusion progressive dans les programmes. Il évoque également l'émergence de formations spécialisées en agriculture biologique, particulièrement populaires auprès des adultes en reconversion professionnelle. L'auteur conclut en soulignant les tensions entre les différentes visions de l'agriculture dite durable au sein de l'enseignement agricole
Hybodont shark remains from Campanian (Upper Cretaceous) continental deposits of southern France
No full textInternational audienceThe hybodont shark (Elasmobranchii, Hybodontiformes) material from the Campanian of two non-marine localities in southern France are described. Some teeth and a dorsal fin spine from the upper Campanian of Velaux are assigned to the genus Meristodonoides (Hybodontidae), whereas a single tooth from the lower Campanian of Villeveyrac is referred to Parvodus (Lonchidiidae), a genus hitherto unknown in the Upper Cretaceous. Among the latest Cretaceous continental ichthyofaunas of the European archipelago, hybodont sharks may have been minor relictual components with spatially restricted distributions, as suggested by their scarcity in the fossil assemblages from France and Romania combined with their apparent absence in other areas (Iberian Peninsula, Hungary)
Differences in VLE adoption: longitudinal and large-scale analysis of contextual effects on French teachers' TEL practices
No full textInternational audienceAgainst the widespread use of virtual learning environments (VLEs) in French schools, this research examines their adoption by primary and secondary school teachers by detecting digital maturity profiles based on activity traces. The aim is to analyze the diversity and intensity of the activities carried out in VLEs to identify these profiles and better understand the conditions of their emergence. Based on the statistical processing of VLE data from 144,900 teachers in three academies over 2 school years, we constructed three indicators (MatU, MatD, MatF) to qualify the use in terms of combination, diversity, and frequency of VLE services used. The results reveal five general profiles that differ according to the academic district, the level of education, or the period in which the VLE was deployed. This shows that digital maturity is strongly linked to contextual variables. These profiles suggest that some contexts favor the adoption of complex, collaborative uses, especially in schools that adopted VLE just after the health crisis. The study thus highlights the role of the institutional framework in structuring and sustaining the use of digital technologies in education
Combien de balais pour une sorcière ?: Approche anthropo-analytique de la sorcierisation des femmes vieillissantes dans le contexte social contemporain
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Target trial emulation to replicate randomised clinical trials using registry data in multiple sclerosis
No full textInternational audienceBackground: Target trial emulation (TTE) offers a formal framework for causal inference using observational data, but its validity must be evaluated in each research domain by replicating randomised clinical trials (RCTs). We aimed to replicate eight RCTs evaluating the efficacy of disease-modifying therapies (DMTs) in multiple sclerosis (MS) using French registry data.Methods: This multicentre, retrospective, observational study was conducted using data extracted in December 2023 from the Observatoire Français de la Sclérose en Plaques (OFSEP) database. For each emulated trial, patients were included when they initiated one of the DMT evaluated in the corresponding RCT and met its inclusion criteria. Clinical outcomes were the annualised relapse rate and 3-month confirmed Expanded Disability Status Scale progression. Radiological outcomes were new/enlarged T2-lesions and new gadolinium-enhanced T1-lesions on a brain MRI. A targeted maximum likelihood estimator was used to estimate the treatment effect adjusted for confounding factors between groups and corrected for censoring and missing outcome assessment.Results: 14 111 patients were included in eight emulated trials: ASSESS (fingolimod vs glatiramer acetate), BEYOND (interferon beta vs glatiramer acetate), CONFIRM (dimethyl fumarate (DMF) vs glatiramer acetate), OPERA (ocrelizumab vs interferon beta), REGARD (interferon beta vs glatiramer acetate), RIFUND-MS (rituximab vs DMF), TENERE (teriflunomide vs interferon beta) and TRANSFORMS (fingolimod vs interferon beta). Treatment effects estimated in emulated trials were concordant with RCT findings in seven of eight trials for relapse rate, and in all six trials assessing disability progression. Radiological outcomes were more challenging to replicate; concordance was achieved in three of five trials for new T2-lesions, and one of four trials for new gadolinium-enhanced T1-lesions.Conclusion: The combined use of a TTE methodology and high-quality registry data is a valid tool to evaluate treatment effectiveness in MS
Hommage à Janine Bouscaren. Linguiste, enseignante, écrivaine
No full textInternational audienceCe volume rend hommage à Janine Bouscaren, disparue en 2023, qui a formé et inspiré de nombreux linguistes anglicistes et a contribué à la diffusion de la Théorie des opérations prédicatives et énonciatives d’Antoine Culioli. Ont participé à cet ouvrage d’anciens étudiants et collègues influencés par ses enseignements et sa recherche. Ils ont souhaité refléter la multiplicité de ses intérêts et de ses talents, et mettre en relief la filiation avec ses travaux, tout en évoquant des aspects de sa biographie, comme universitaire et comme écrivaine, qui faisaient de JanineBouscaren une personnalité hors du commun.Une première partie du volume retrace sa carrière, à travers des entretiens avec Janine elle-même et différents témoignages de plusieurs générations de collègues. Les articles de la seconde partie s’inscrivent dans le sillage de ses enseignements et de sa recherche, et en illustrent différentes facettes
Sustainable catalytic solutions: SDS-modified Nb2O5/Al2O3 for Efficient glycerol dehydration
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A New Experimental Protocol for Assessing Hominoid Assisted Arboreal Bipedalism
No full textInternational audienceArboreal bipedalism is suggested as a precursor and adaptive locomotor mode for the immediate ancestor of hominin terrestrial bipedalism, yet detailed investigation of its locomotor biomechanics is hindered by its low frequency and observation difficulties in free-ranging hominoids. Further difficulties are faced in the creation and installation of a suitable experimental setup in natural settings. Captive studies may potentially reduce logistical issues, but data on arboreal bipedalism are scarce. We present an experimental design and protocol for collecting video data on arboreal bipedalism in captive primates, from which qualitative and quantitative gait data can be extracted. Our protocol increases the frequency of this rare behavior. Data were collected on six adult chimpanzees (three males, three females) at La Vallée des Singes, Romagne, France. The chimpanzees voluntarily engaged with a simulated arboreal foraging scenario consisting of two parallel PVC tubes and a high-value food reward. Five GoPro cameras recorded interactions with the experimental equipment. For validation of the effectiveness of our experimental design, protocol interactions were identified as successful (activity completed) or unsuccessful. All age and sex classes had successful interactions. Full strides were observed alongside the identification of two forms of arboreal bipedalism, forward-facing and sideways. This highlights the variation within the arboreal bipedalism locomotor category and the capacity for our experimental design to provide suitable data for gait parameter analysis and interspecies comparisons. Our protocol thus permits detailed investigation of arboreal bipedalism's role in the evolution of hominin bipedalism
Hybrid Supervised Learning and Constrained Optimization for Task-Space Trajectory Generation in Tendon-Driven Continuum Robots
No full textInternational audienceTendon-driven continuum robots (TDCRs) offer exceptional dexterity and compliance, making them suitable for manipulation in constrained and complex environments. However, solving the inverse-kinematics (IK) problem with sufficient accuracy and physical feasibility remains challenging due to nonlinear curvature coupling and actuation uncertainties. This paper presents a hybrid inverse-kinematics framework that integrates supervised deep learning with constrained optimization to achieve precise and physically consistent task-space trajectory tracking. Neural networks provide fast initial pose-to-configuration estimates, which are subsequently refined through constraint-aware optimization, ensuring geometric and actuation feasibility. The training data were generated from optimal IK solutions obtained via constrained optimization across sixteen trajectory-constraint combinations, covering four representative trajectories circular, elliptical, helical, and butterfly, and four end-effector orientation modes. Extensive simulations on a two-segment tendon-driven continuum robot demonstrated statistically significant improvements (p ≤ 0.01) in both position and orientation accuracy compared with standalone neural or optimization-based approaches. The hybrid method achieves micrometerlevel positional accuracy and micro-degree-level orientation precision while maintaining computational efficiency suitable for real-time applications. The present work focuses on a quasi-static modeling and trajectory-generation framework. Future work will extend constraint handling to include dynamic obstacle avoidance and smoothness optimization, explore global solvers such as genetic algorithms and particle swarm optimization, and address sim-to-real transfer through adaptive learning for multi-segment robots in realistic environments