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PERCEPTION DES RISQUES DE L’UTILISATION PEDAGOGIQUE DE L’INTELLIGENCE ARTIFICIELLE DANS L’ENSEIGNEMENT SUPÉRIEUR
No full textInternational audienceCette étude examine l’utilisation de l’IA par les enseignants-chercheurs ainsi que les risques pédagogiques perçus liés à son adoption. Les résultats obtenus de l’analyse des données quantitatives recueillies auprès d’enseignants-chercheurs révèlent, d’une part, un recours timide à l'IA pour les travaux de recherche et d’enseignement. D’autre part, les enseignants reconnaissent des risques quant à son utilisation dans la formation en général et spécifiquement pour répondre aux questions des étudiants plutôt que pour la génération de contenus. Pour tirer le meilleur profit de cette technologie, l’étude suggère des actions de renforcement de capacités des enseignants-chercheurs dans l’intégration de l’IA dans la recherche et l’enseignement
La Ligue de l'Enseignement et le Compte Personnel de Formation
No full textCe travail centré sur le Compte Personnel de Formation (CPF) se penche sur la manière dont l'INFREP, de l'UFOLEP et des fédérations de la Ligue mobilisent ce mode de financement. Ce rapport est fondé sur les bases de données mises en ligne par la Caisse des Dépôts et Consignations ; son approche est donc fondé sur des méthodes quantitatives. Dans un contexte de tarissement des subventions publiques, il s'agit pour la Ligue de diversifier les sources de revenus, en entrant dans le jeu de la compétition entre organismes de formation pour cette manne financière. Les données permettent d'objectiver le positionnement singulier de la Ligue sur des formations longues, certifiantes et majoritairement inscrites au Répertoire National des Certifications Professionnelles (RNCP). Au-delà du seul cas de la Ligue, les bases comme celles du CPF permettent de mieux comprendre l'évolution de l'offre de formation éligible au CPF, prise dans son ensemble : nous prenons le cas des formations au BPJEPS ou d'éducateurs sportifs, mais aussi d'acteurs autres que la Ligue susceptibles de se positionner sur des thématiques proches
First light for the GRAVITY+ Adaptive Optics: Extreme adaptive optics for the Very Large Telescope Interferometer
No full textInternational audienceGRAVITY+ improves by orders of magnitude the sensitivity, sky-coverage, and contrast of the Very Large Telescope Interferometer (VLTI). A central part of this project is the development of Gravity Plus Adaptive Optics (GPAO), a dedicated high-order and laser-guide star adaptive optics (AO) system for VLTI. GPAO consists of four state-of-the-art AO systems that equip all 8 m class Unit Telescopes (UTs) for the wavefront correction of the VLTI instruments. It offers both visible and infrared natural guide star (NGS) and laser guide star (LGS) operations. The paper presents the design, operations, and performances of GPAO. We illustrate the improvement brought by GPAO with interferometric observations obtained during the commissioning of the NGS mode at the end of 2024. These science results include the first optical interferometry observations of a redshift z ~ 4 quasar, the spectroscopy of a cool brown-dwarf with magnitude K ~ 21.0, the first observations of a Class I young star with GRAVITY, and the first sub-micro arcsecond differential astrometry in the optical. Together with the entire GRAVITY+ project, the implementation of GPAO is a true paradigm shift for observing the optical Universe at very high angular resolution.GRAVITY+ améliore de plusieurs ordres de grandeur la sensibilité, la couverture du ciel et le contraste de l’interféromètre du Very Large Telescope (VLTI). Une partie centrale de ce projet est le développement de l’optique adaptative Gravity Plus (GPAO), un système d’optique adaptative (AO) dédié, à haut ordre, utilisant des étoiles guides laser pour le VLTI. La GPAO se compose de quatre systèmes d’optique adaptative de pointe qui équipent chacun des télescopes unitaires (UT) de classe 8 mètres pour la correction du front d’onde des instruments du VLTI. Il permet des observations avec étoiles guides naturelles (NGS) et étoiles guides laser (LGS), à la fois dans le visible et dans l’infrarouge. L’article présente la conception, le fonctionnement et les performances du GPAO. Nous illustrons les améliorations apportées par le GPAO grâce à des observations interférométriques réalisées lors de la mise en service du mode NGS à la fin de l’année 2024. Ces résultats scientifiques incluent les premières observations en interférométrie optique d’un quasar à décalage vers le rouge z ~ 4, la spectroscopie d’une naine brune froide de magnitude K ~ 21,0, les premières observations d’une jeune étoile de classe I avec GRAVITY, ainsi que la première astrométrie différentielle optique à une précision sub-microseconde d’arc. Avec l’ensemble du projet GRAVITY+, la mise en œuvre du GPAO constitue un véritable changement de paradigme pour l’observation de l’Univers optique à très haute résolution angulaire
Le Parlement à l'épreuve du temps: Entre urgence politique et exigence délibérative
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White paper on the relevance of the European Solar Telescope (EST) for the French heliophysics community
No full textThe project of the European Solar Telescope aims to provide a state-of-the art infrastructure to study the Sun and its interactions with Earth and the heliosphere. This 4.2m aperture telescope will be equipped with multi conjugate adaptive optics, light-polarisation analyser, imaging spectrograph and integral field unit spectrographs. It will provide unprecedented observations of the solar photosphere and chromosphere and of the dynamical events and features that pertains to the low solar atmosphere. The EST project is presently in a phase of crystallisation, aiming at the creation of an European Research Infrastructure Consortium. While the French community has continuously been associated with the development of the EST project, some specific scientific aspects are more particularly relevant for the French astrophysics and heliophysics communities. The present review highlights the scientific research axes of high interest from the French community that shall strongly benefit from EST. The later will not only advance numerous topics of solar physics, as well as solar adaptive optics developments, but will also provide unrivaled datasets of high interest in the framework of space weather. This review also aims to highlight the space weather use that can be done with future EST observations, that will be particularly relevant for French heliophysicists
Forest Herding and Tree Foddering in Neolithic Europe: Comparing δ13C Values in Caprine Enamel with Archaeobotanical Evidence at Lake Shore Settlements in Switzerland and the French Jura
No full textInternational audienceForest grazing and tree leaf foddering were once widespread in Europe. Stable carbon isotope analysis of faunal remains can help investigate the practice back to the Neolithic. The approach presupposes the empirical definition of a threshold δ 13 C value beyond which a forest component in diet is arguable. This objective can be attained in contexts where animals feeding on forest trees were demonstrated independently. We analyzed caprine teeth from the sites of Arbon-Bleiche 3 (34th century BCE, Switzerland), where forest fodder was directly evidenced from macroremains in caprine faeces; and from Clairvaux (39th–37th c. BCE) and Chalain (32nd–30th c. BCE; French Jura) where it was suggested from thousands of branches accumulated in the occupation layers. Sequential isotope analysis in caprine tooth enamel revealed δ 13 C values ≤ −14‰ at Clairvaux and Chalain, and ≤ −15‰ and down to −16.7‰ at Arbon during winter, the lowest recorded to date in Neolithic Europe. A more 13 C-depleted signal at Arbon, associated with significantly lower δ 18 O values, may reflect the abrupt cooler and wetter climatic event recorded at this time in the Lake Constance sediments, causing harsher winters and the need for complementary feed in the form of tree leaves, as well as a potential tree-line decline leading to a greater proximity of the fir forest. Inter-individual variability reflects adaptability of extensive herding systems subjected to environmental uncertainties. These results confirm that in these chronocultural contexts, forests were fully integrated into husbandry systems, shaping practices and animal behaviors, and potentially contributing to the reshaping of the landscape
UNIONS: The Ultraviolet Near-Infrared Optical Northern Survey
No full textInternational audienceThe Ultraviolet Near-Infrared Optical Northern Survey (UNIONS) is a "collaboration of collaborations" that is using the Canada-France-Hawai'i Telescope, the Pan-STARRS telescopes, and the Subaru Observatory to obtain images of a core survey region of 6250 deg of the northern sky. The point source depth of the data, as measured within a 2-arcsecond diameter aperture, are in AB magnitudes. UNIONS is addressing some of the most fundamental questions in astronomy, including the properties of dark matter, the growth of structure in the Universe from the very smallest galaxies to large-scale structure, and the assembly of the Milky Way. It is set to become the major ground-based legacy survey for the northern hemisphere for the next decade and provides an essential northern complement to the static-sky science of the Vera C. Rubin Observatory's Legacy Survey of Space and Time. UNIONS supports the core science mission of the {\it Euclid} space mission by providing the data necessary in the northern hemisphere for the calibration of the wavelength dependence of the {\it Euclid} point-spread function and derivation of photometric redshifts in the North Galactic Cap. This region contains the highest quality sky for {\it Euclid}, with low backgrounds from the zodiacal light, stellar density, extinction, and emission from Galactic cirrus. Here, we describe the UNIONS survey components, science goals, data products, and the current status of the overall program
Muscle Retracting Sign in Colorectal Macronodular Lesions: Prevalence, ESD Outcomes, and Submucosal Cancer Predictors
No full textInternational audienc
Reconfigurations Robotiques
No full textLes technologies dites intelligentes (robots, IA, systèmes automatisés) semblent s’imposer à nous de façon inexorable. Leur diffusion suscite une véritable effervescence collective nourrie de promesses, d’inquiétudes, de récits d’innovation ou d’asservissement, de scénarios eschatologiques… Dans ce contexte, il devient difficile de distinguer ce qui relève du réel ou de l’imaginaire.Ce numéro spécial aborde les effets de ces objets dans des mondes sociaux aussi divers que l’agriculture, l’industrie, la prospective militaire, le jeu de Go, la science-fiction ou encore le droit. En s’appuyant sur la notion de reconfiguration, il montre comment l’automatisation transforme en profondeur les pratiques professionnelles, les savoirs experts, les institutions, mais aussi comment elle s’articule avec des représentations et des mises en récit.Les contributions réunies dans ce dossier examinent les modalités d’existence des systèmes intelligents, les cultures épistémiques associées à leur conception, les bouleversements et les rapports nouveaux qu’ils provoquent, en se concentrant sur leurs dimensions matérielle, sociale et imaginaire. Elles dressent une cartographie des mutations en cours et soulève une question centrale : quelle société ces technologies sont-elles en train de construire
Euclid Quick Data Release (Q1). First Euclid statistical study of galaxy mergers and their connection to active galactic nuclei
No full textInternational audienceGalaxy major mergers are indicated as one of the principal pathways to trigger active galactic nuclei (AGN). We present the first statistical analysis of the major merger and AGN connection in the Euclid Deep Fields, and showcase the statistical power of the Euclid data. We constructed a stellar-mass-complete (M_⋆>10^ M_⊙) sample of galaxies from the quick data release (Q1) in the redshift range z=0.5--2. We selected AGN using X-ray detections, optical spectroscopy, and mid-infrared (MIR) colours, and by processing observations with an image decomposition algorithm. We used convolutional neural networks trained on cosmological hydrodynamic simulations to classify galaxies as mergers and non-mergers. We found a larger fraction of AGN in mergers compared to the non-merger controls for all AGN selections, with AGN excess factors ranging from two to six. The largest excess we observed was in the MIR AGN. Likewise, a generally larger merger fraction (f_̊m merg) was seen in active galaxies than in the non-active controls, with the excess depending on the AGN selection method. Furthermore, we analysed f_̊m merg as a function of the AGN bolometric luminosity (L_̊m bol) and the contribution of the point-source component to the total galaxy light in the IE-band (f_ PSF ) as a proxy for the relative AGN contribution fraction. We uncovered a rising f_̊m merg, with an increasing f_ PSF up to f_ PSF ≃ 0.55, after which we observed a decreasing trend. In the range f_ PSF = 0.3--0.7, mergers appear to be the dominant AGN fuelling mechanism. We then derived the point-source luminosity (L_ PSF ) and showed that f_̊m merg monotonically increases as a function of L_ PSF at z<0.9, with f_ ̊m merg ≥50% for L_ PSF ≃ 2 . Similarly, at , f_̊m merg rises as a function of L_ PSF though mergers do not dominate until L_ PSF ≃ 10^ . For the X-ray and spectroscopically detected AGN, we derived the bolometric luminosity, L_ bol, which has a positive correlation with f_ merg for X-ray AGN, while there is a less pronounced trend for spectroscopically selected AGN due to the smaller sample size. At L_ bol AGN mostly reside in mergers. We conclude that mergers are most strongly associated with the most powerful and dust-obscured AGN, which are typically linked to a fast-growing phase of the supermassive black hole, while other mechanisms, such as secular processes, might be the trigger of less luminous and dominant AGN.</jats:p