HAL Portal UDL Université de Lyon
Not a member yet
327890 research outputs found
Sort by
Synergistic action of crystallophore and imaging‐crystallophore enhances the production and imaging of protein crystals
No full textInternational audienceThe synthesis and photophysical characterization of a new family of terbium(III) complexes called Imaging ‐crystallophore, substituted by π‐conjugated antennas, is reported. Previous crystallophore variants (such as Tb‐Xo4) have shown very interesting nucleating properties to obtain high‐quality protein crystals. In addition, the Imaging ‐crystallophore emits in the green and accumulates in the protein crystals, enabling very easy crystal detection using fluorescence microscopy under one‐photon but also under two‐photon excitations. X‐ray diffraction crystallography and molecular dynamics simulations demonstrate that the binding site of the Imaging ‐crystallophore in hen‐egg white lysozyme (HEWL) is similar to that of the Tb‐Xo4 but present additional hydrophobic interactions with the conjugated antennas. However, its nucleating properties are not as effective as those of Tb‐Xo4. Finally, we emphasize the synergy between the two generations of crystallophore by preparing and analyzing the properties of the mix (10/0.2) corresponding to a mixture of Tb‐Xo4 and Imaging ‐crystallophore. By combining the best of nucleating and imaging properties, we can easily obtain and detect high‐quality protein crystal
L'autel des Muses au sanctuaire de l'Hélicon sur le territoire de Thespies
No full textInternational audienc
Amélioration de l'interprétabilité des explications de SHAP grâce à la découverte de sous-groupes
No full textInternational audienceL'intégration de modèles prédictifs en médecine nécessite des explications compréhensibles pour soutenir la décision clinique. Cette étude préliminaire propose une approche post hoc, model-agnostic combinant SHAP et la découverte de sous-groupes afin de générer des règles explicites de type SI–ALORS. Cette combinaison permet de produire simultanément des explications locales et globales, tout en offrant des explications plus précise que les facteur d'importance de SHAP et une compréhension plus riche des interactions entre variables. Les expériences réalisées sur quatre jeux de données médicaux montrent une large couverture et une caractérisation précise des classes, avec des valeurs élevées de WRAcc et de lift. Les explications locales obtenues présentent une fidélité supérieure à 90% pour les modèles binaires. Bien que développée dans un contexte médical, l'approche peut être appliquée à tout domaine nécessitant intelligibilité et confiance dans les modèles prédictifs
In-core Gamma and Neutron Irradiation of Optical Materials used in the Design of an Optical Sensor for Pressurized Water Research Reactor
No full textInternational audienc
L'octroi de véhicules de fonction : la sobriété au prisme contentieux
No full textInternational audiencele cadre légal et règlementaire d’attribution des véhicules de fonctions aux agents publics est d’une lecture assez complexe, le sujet donnant fréquemment lieu à des rapports de chambres régionales des comptes mettant en cause la gestion des collectivités territoriales en la matière. Dominé par l’impératif de nécessités du service, il est également percuté directement par le contexte budgétaire et les impératifs de protection de l’environnement, qui viennent d’autant restreindre la liberté des employeurs publics et incitent à une politique de sobriété. Il en résulte un encadrement serré des conditions d’octroi d’un véhicule de fonction, décision que les employeurs publics sont invités à prendre avec la plus grande parcimonie
CIP-Net: Continual Interpretable Prototype-based Network
No full textInternational audienceContinual learning constrains models to learn new tasks over time without forgetting what they have already learned. A key challenge in this setting is catastrophic forgetting, where learning new information causes the model to lose its performance on previous tasks. Recently, explainable AI has been proposed as a promising way to better understand and reduce forgetting. In particular, self-explainable models are useful because they generate explanations during prediction, which can help preserve knowledge. However, most existing explainable approaches use post-hoc explanations or require additional memory for each new task, resulting in limited scalability. In this work, we introduce CIP-Net, an exemplar-free self-explainable prototype-based model designed for continual learning. CIP-Net avoids storing past examples and maintains a simple architecture, while still providing useful explanations and strong performance. We demonstrate that CIP-Net achieves state-of-the-art performances compared to previous exemplar-free and self-explainable methods in both task-and class-incremental settings, while bearing significantly lower memory-related overhead. This makes it a practical and interpretable solution for continual learning
Recension de « Patrick J. Geary, Comment la génétique réécrit l’histoire du Moyen Âge, Paris, CNRS éditions, 2025 »
No full textInternational audienc
Tracing a Wet Past and Diverse Provenances in Gale Crater, Mars, With Lithium Content Using ChemCam on the Curiosity Rover
No full textInternational audienceThe incompatible behavior of Lithium during magmatic differentiation and high mobility during aqueous alteration make it a valuable tracer of crustal processes on Mars. Its preferential incorporation into secondary phyllosilicates further links Li to clay-forming environments, which are critical for evaluating past aqueous activity and habitability. The ChemCam instrument aboard the Mars Science Laboratory Curiosity rover enables remote Li detection through laser-induced breakdown spectroscopy (LIBS) and has provided the first in situ measurements of Li in Martian rocks. Here, we present the first stratigraphically contextualized analysis of Li abundance and variability in Gale crater based on almost 14,000 ChemCam observations across seven major bedrock classes. Lithium abundances are elevated relative to Martian meteorites, particularly shergottites, and broadly track phyllosilicate distribution, increasing in clay-rich units and decreasing where phyllosilicates are absent. However, this relationship breaks down in the Clay-sulfate Transition region, where Li remains elevated despite low phyllosilicate content. The persistence of high Li in this region, as well as in basaltic rocks, points to the presence of a Li-enriched igneous provenance near Gale crater and emphasizes that the Martian crust is more compositionally diverse than that inferred from Martian meteorites alone