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Towards Polyoxometalate Nanoelectronics
No full textPolyoxometalates form a large family of molecular oxide clusters of the early transition metals with unique and tunable properties (multi-redox, thermal and chemical robustness, magnetic). We review more than 30 years of experimental research on the electron transport properties of polyoxometalates devices, from thin films and self-assembled monolayers down to single-molecule junctions. We focus on the relationship between the polyoxometalate structures (structural type, nature of metals and heteroatoms, role of the counterions, redox states, electrode linkers and functional ligands) and the electronic structures of the polyoxometalate-based devices (energy positions of the molecular orbitals, energy offset at the interfaces). Then, we critically discuss the performances of polyoxometalates in nanoelectronics devices: capacitance and resistive switching memories, spintronics, quantum bits and neuromorphic devices. We conclude with a discussion about pending issues and perspectives
Cartographier l'écosystème des e-pétitions via les médias sociaux :mobilisation dans l'UE autour d'enjeux et idéologies
No full textInternational audienceWe study petition-related mobilization on Social Media across issues and ideologies. Using calls to sign petitions on X in the seven most spoken EU languages, we build the first multi-platform, multi-language map of the e-petitioning ecosystem. To ensure cross-language and cross-ideology comparability, we infer call for signatures’ issues using ManifestoBERTa and users' ideological orientation via Ideology Scaling methods calibrated using expert survey data. We classify active individuals into an ontology of mobilization types. Results show that e-petition activism is issue-specific and short-lived, with only a small portion of individuals engaging in sustained mobilization. We characterize differences in e-activism across the Left-Right spectrum, with Right-leaning users being most active on issues like political corruption and traditional morality, while environmental protection sees low engagement levels compared to its reach.Nous étudions la mobilisation liée aux pétitions sur les réseaux sociaux, à travers différents enjeux et idéologies. En nous appuyant sur des appels à la signature de pétitions diffusés sur X, dans les sept langues les plus parlées de l’Union européenne, nous construisons la première cartographie multi-plateforme et multilingue de l’écosystème de l’e-pétitionnement. Afin de garantir la comparabilité interlinguistique et inter-idéologique, nous inférons les thématiques des appels à signatures à l’aide de ManifestoBERTa et estimons l’orientation idéologique des utilisateurs au moyen de méthodes de Ideology Scaling calibrées à partir de données d’enquêtes d’experts. Nous classons les individus actifs au sein d’une ontologie des types de mobilisation. Les résultats montrent que l’activisme par e-pétition est fortement dépendant des enjeux et de courte durée, seule une minorité d’individus s’engageant dans une mobilisation soutenue. Nous mettons en évidence des différences marquées dans l’e-activisme le long du clivage gauche-droite : les utilisateurs orientés à droite sont les plus actifs sur des enjeux tels que la corruption politique et la morale traditionnelle, tandis que la protection de l’environnement suscite des niveaux d’engagement relativement faibles au regard de sa portée
L’Orient, par-delà le romantisme
No full textInternational audienceIn 1856, Lorédan Larchey (1831–1902) published a short work on Constantinople. Breaking with the romantic tradition of travel writing, he documented a country undergoing profound change, far removed from Orientalist clichés, with precision and a touch of humour. Reflecting the intellectual networks of Parisian student life, the work was published the following year by Auguste Poulet-Malassis, publisher of Les Fleurs du Mal: it was the fruit of intellectual and literary friendships on the fringes of the École des ChartesAbout: Lorédan Larchey, Un mois à Constantinople (A Month in Constantinople), Janvier 1855, Alençon, Poulet-Malassis, 1856. Purchased in bookshops, Bellamys World / Book Heritage (Lebanon), 2025. Library of the École nationale des chartes - PSL, 8 R 321.Lorédan Larchey (1831-1902) publie en 1856 un opuscule sur Constantinople. Rompant avec la tradition romantique du récit de voyage, il documente un pays en pleine mutation loin des clichés orientalistes, avec précision et non sans humour. Reflet des réseaux intellectuels du monde étudiant parisien, l’ouvrage est publié par Auguste Poulet-Malassis, éditeur des Fleurs du Mal dès l’année suivante : il est le fruit d’amitiés intellectuelles et littéraires dans les marges de l’École des chartes.A propos de : Lorédan Larchey, Un mois à Constantinople, janvier 1855, Alençon, Poulet-Malassis, 1856. Achat en librairie, Bellamys World / Book Heritage (Liban), 2025. Bibliothèque de l’École nationale des chartes - PSL, 8 R 321
Le tombeau ouvert : mise en perspective de la perte et du deuil dans Le Monde sans vous
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Wikipedia as an Open Access Tool for Restituting Knowledge on African Past
No full textThe Digital OrientalistThe Langarchiv project, led by Camille Lefebvre (CNRS/EHESS), uses Wikipedia as a tool for restituting knowledge about African history, particularly that of the Sahara and Sahel regions during the 18th and 19th centuries. As part of this initiative, master’s students at EHESS are trained to write or enhance Wikipedia articles about African intellectual and historical figures, who are often underrepresented in the encyclopedia. Despite the challenges posed by Wikipedia’s strict rules, the project has already resulted in the creation or improvement of 19 articles, as well as translations into Hausa and German. The initiative aims both to address gaps in African history and to raise awareness among young researchers about collaborative tools like Wikipedia.Le projet Langarchiv, dirigé par Camille Lefebvre (IMAF, CNRS/EHESS), utilise Wikipedia comme outil de restitution des savoirs sur l’histoire africaine, notamment celle du Sahara et du Sahel aux XVIIIe et XIXe siècles. Dans ce cadre, des étudiants en master à l’EHESS sont formés pour rédiger ou enrichir des articles Wikipedia sur des figures intellectuelles et historiques africaines, souvent sous-représentées dans l’encyclopédie. Malgré les défis liés aux règles strictes de Wikipedia, le projet a déjà permis la création ou l’amélioration de 19 articles, ainsi que des traductions en hausa et en allemand. L’initiative vise à la fois à combler les lacunes sur l’histoire africaine et à sensibiliser les jeunes chercheurs et chercheuses aux outils collaboratifs comme Wikipedia
Euclid preparation. 3D reconstruction of the cosmic web with simulated Euclid Deep spectroscopic samples
No full textInternational audienceThe ongoing Euclid mission aims to measure spectroscopic redshifts for approximately two million galaxies using the H line emission detected in near-infrared slitless spectroscopic data from the Euclid Deep Fields (EDFs). These measurements will reach a flux limit of in the redshift range , opening the door to numerous investigations involving galaxy evolution, extending well beyond the mission's core objectives. The achieved H luminosity depth will lead to a sufficiently high sampling, enabling the reconstruction of the large-scale galaxy environment. We assess the quality of the reconstruction of the galaxy cosmic web environment with the expected spectroscopic dataset in EDFs. The analysis is carried out on the Flagship and GAEA galaxy mock catalogues. The quality of the reconstruction is first evaluated using geometrical and topological statistics measured on the cosmic web, namely the length of filaments, the area of walls, the volume of voids, and its connectivity and multiplicity. We then quantify how accurately gradients in galaxy properties with distance from filaments can be recovered. As expected, the small-scale redshift-space distortions, have a strong impact on filament lengths and connectivity, but can be mitigated by compressing galaxy groups before skeleton extraction. The cosmic web reconstruction is biased when relying solely on H emitters. This limitation can be mitigated by applying stellar mass weighting during the reconstruction. However, this approach introduces non-trivial biases that need to be accounted for when comparing to theoretical predictions. Redshift uncertainties pose the greatest challenge in recovering the expected dependence of galaxy properties, though the well-established stellar mass transverse gradients towards filaments can still be observed
Managing generativity in innovation: from control to emergence: Call for Paper
No full textInternational audienceEmerging technologies such as generative AI or autonomous systems introduce new forms of generativity, namely the capacity to produce unexpected, evolving, and selfpropagating outcomes. These technologies challenge conventional management approaches. They do so by producing outcomes that cannot be fully anticipated or predefined, thereby undermining the assumptions of stability, linearity and alignment theorized in traditional management and innovation literature. Importantly, the emergence of AI provides new challenges on, for instance, how can organizations manage generative technologies? What practices, processes and structures enable organisations to leverage generative technologies? This track explores how organisations understand, design, and manage generativity as a new condition for creativity and transformation. We invite theoretical, empirical, and design-oriented contributions examining how generativity reshapes organisational creativity, learning, and strategy. The track aims to bring together researchers studying the creative, organisational, and epistemic implications of generative technologies. Description:Digitalisation has transformed the way organisations innovate, yet a new phase is unfolding, one that is characterised not merely by automation or connectivity, but by generativity. Generative technologies, including GenAI, synthetic biology, computational design, and adaptive systems, create artefacts, knowledge, and possibilities that evolve autonomously and perpetually. These technologies are not only tools or enablers; they are complex systems, capable of evolving autonomously and reconfiguring the very environments in which they operate (Thomas & Tee, 2022). This shift challenges traditional managerial models founded on prediction, control, and eRiciency. Managing innovation in generative contexts requires new forms of creativity, coordination, and learning (Haefner et al., 2021).</div