Abelian varieties are de Rham K(π,1)K(π,1)

Motivated by the work of Esnault-Hai, one has the notion of de Rham $K(\pi,1)$ schemes, defined as follows. Given a smooth proper geometrically connected scheme $X$ over a field $k$ of characteristic 0 and a base point $x \in X (k)$, one can define its differential fundamental group $\pi^{\mathrm{diff}}(X/k)$, which comes from the Tannakian duality of the category of coherent integrable connections on $X$. Using the formalism of $\delta$-functors, one can define natural morphisms between the group-scheme cohomology of $\pi^{\mathrm{diff}}(X/k)$ and the de Rham cohomology of $X$. One says that $X$ with $x\in X(k)$ is {de Rham $K(\pi,1)$} if such morphisms are all isomorphisms. In this article, we first prove that abelian varieties in characteristic $0$ are de Rham $K(\pi,1)$. In the second part of the article, we study the group-scheme cohomology of the abelianization of the differential fundamental group of a smooth proper geometrically connected scheme via its Albanese variety

Chemsex et usages sexualisés de drogues : définitions, principaux chiffres et principales substances utilisées

International audienceSexualized drug use (SDU) and chemsex are defined by using one or several psychoactive substances for fostering, improving, or prolonging sexual intercourses. Chemsex represents a specific subtype of SDU historically rooted in the community of men who have sex with men (MSM), shaped by distinct cultural, community, and health factors, particularly related to HIV and the use of dating apps. In France, approximately 13–14% of MSM report chemsex practices, with high levels of sexual risk-taking and HIV prevalence, especially among those seeking addiction care. Chemsex primarily involves psychostimulants (cathinones, methamphetamine, MDMA, cocaine) and synthetic sedatives (GHB/GBL, ketamine), used to enhance disinhibition, endurance, sensory intensity, and social or sexual facilitation. These substances carry substantial risks, including overdose, severe dependence, psychiatric symptoms, amnesia, loss of control, and physical complications. Other substances – such as alcohol, cannabis, poppers, and phosphodiesterase-5 inhibitors – often play an underestimated adjunctive role. Beyond chemsex, SDU encompasses far more heterogeneous populations, including women and non-MSM individuals, but remains poorly documented epidemiologically. The spread of substances traditionally associated with chemsex into non-MSM settings, alongside the frequent involvement of “non-chemsex” drugs, highlights the need for prevention, harm reduction, and care strategies that reflect the evolving realities of sexualized substance use.Les usages sexualiseś de drogues (USD) sont definis comme l'usage d'une ou de plusieurs substances psychoactives pour faciliter, ameĺiorer ou prolonger un rapport sexuel. Le chemsex deśigne un sous-type particulier d'USD historiquement issu de la communauté des hommes ayant des relations sexuelles avec des hommes (HSH), avec des determinants culturels, communautaires et sanitaires spećifiques, notamment en lien avec le VIH et les applications de rencontre. En France, environ 13-14 % des HSH dećlarent des pratiques de chemsex, avec des niveaux eĺeveś de comportements sexuels à risque et de prevalence du VIH, particulierement chez les personnes demandant un accompagnement addictologique. Le chemsex repose principalement sur l'usage de psychostimulants (cathinones, methamphetamine, MDMA et cocaïne) et de sedatifs de synthese (GHB/GBL, ketamine), rechercheś pour leurs effets de deśinhibition, d'endurance, d'intensification sensorielle et de facilitation relationnelle. Ces substances exposent toutefois à des risques majeurs : surdoses, deṕendances severes, troubles psychiatriques, amneśies, pertes de contrôle et complications somatiques. D'autres produits, comme l'alcool, le cannabis, les poppers ou les inhibiteurs de la phosphodiesteŕase 5, jouent un rôle adjuvant souvent sous-estime. Au-delà du chemsex, les USD concernent des populations beaucoup plus heteŕogeǹes, incluant femmes et personnes non-HSH, mais restent encore peu etudieś. L'evolution des pratiques et la diffusion de certaines substances hors du cadre communautaire HSH soulignent la nećessité d'adapter les strateǵies de prevention, de reduction des risques et de soins aux reáliteś actuelles des usages.</div

Micro pulling down melt solidification of Co-doped Al2O3-YAG binary and Al2O3-YAG-ZrO2 ternary eutectics systems and characterization

International audienceShaped Co-doped Al 2 O 3 -YAG and Al 2 O 3 -YAG-ZrO 2 blue-colored eutectic ceramic rods with a diameter of 3 mm were solidified from the melt using the micro-pulling down (μ-PD) technique. The blue color contrast of the rods depends on the Co concentration and the type of eutectic system. Regardless of the Co dopant concentration, mainly two textured phases (Al 2 O 3 -YAG) were observed in the binary system, and three phases (Al 2 O 3 -YAG-ZrO 2 ) with a Chinese script microstructure were observed in the ternary system. The Co concentration in the binary Al 2 O 3 -YAG system does not affect the solidification process or morphology, unlike in the ternary Al 2 O 3 -YAG-ZrO 2 system. In both eutectic systems, the solidified phases are well oriented along specific directions. In the ternary system, only the YAG phase does not strongly deviate from its preferential growth direction (100). The hydrostatic stress in the binary eutectic system is lower than in the ternary eutectic system with the same Co dopant concentration due to the distribution of ZrO 2 particles in the microstructure, which affects residual stresses. The luminescence properties of the Co-doped binary and ternary eutectic systems were investigated

Modeling protonated helium clusters across the size-resolved to the droplet regimes: Structure and low-energy collision dynamics

International audienceA many-body polarizable potential is developed to model HenH+ clusters in their electronic ground state across a broad size range, trained to reproduce quantum chemical CCSD(T) calculations with a basis set of quadruple zeta quality. Putative global minima of small clusters containing up to n = 50 helium atoms exhibit a rigid HeH+He trimer core, around which additional atoms arrange into icosahedral-like motifs. The binding energy inferred from path-integral molecular dynamics simulations displays successive changes in its slope at n &amp;gt; 2, n &amp;gt; 6, and n &amp;gt; 13, and vibrational delocalization, as measured from the inherent structure entropy, is found to be significant already at small sizes. In large clusters, the trimer core is preserved and a much softer second solvation shell of ∼20 atoms is identified. The collision dynamics of a proton impinging on a 1000-atom helium droplet was simulated using ring-polymer molecular dynamics for various conditions and moderate energies in the eV range. Soft capture is found to take place for collision energies of ∼1 eV and below, while 10 eV collisions have the proton piercing through the droplet before being possibly captured back after losing sufficient energy. The resulting sticking cross sections generally follow the predictions of a simple Langevin capture model, extended to account for the finite radius of the helium target, except in the piercing regime. In the low collision energy limit, the sinking of an initial hydrogen atom after sudden ionization is found to be very slow once the trimer core is formed within 2 ps.</jats:p

Simulating Thermal Properties of Bose-Hubbard Models on a Quantum Computer

While recent advances have established efficient quantum algorithms for preparing Gibbs states of finite-dimensional systems, comparable complexity results for bosonic and other infinite-dimensional models remain unexplored. We introduce the first general rigorous Gibbs sampling framework for bosonic many-body systems, showing that physically relevant bosonic models admit gapped dissipative generators, enabling efficient preparation of thermal states. Although our results hold for broad classes of models, we illustrate them using Bose-Hubbard Hamiltonians, both within and beyond the mean-field regime. In both cases, we show that the associated dissipative generators maintain a positive spectral gap, thereby implying exponential convergence to the thermal state. Our argument in the multi-mode case is based on a finite-rank reduction of the dissipative dynamics, which allows us to control the generator via compact perturbations and deduce the discreteness of the spectrum and the stability of the gap. We apply our results to provide efficient preparation of the corresponding Gibbs state on qubit hardware, and by that a quantum algorithm to compute thermal properties of the associated model. This provides the first mathematically controlled route to Gibbs sampling in infinite-dimensional systems, with implications for quantum simulation, thermalization, and many-body complexity, where quantum advantages may arise

A “transient-comonomer” strategy for polycondensation of lignin-derived AB-type aromatic polyesters to high molecular weight

International audienc

Long-term observation of the end-of- treatment sludge quality from a Parisian WWTP treating wastewater from 6.5 M inhabitants

The dataset “Dataset _CakesSAV.xlsx” includes the monthly analysis of 42 micropollutants (trace metals, PAHs, PCBs, ammonium, calcium oxide, magnesium oxide and elementary analysis) of the end-of-treatment sludge (called “cakes”) of SAV. The oldest analyses date back to 1980.The quality of the sludge is commonly characterized by dry matter (DM, in % - 1% = 10 g/L) and volatile matter (VM, in % DM). The mean value for DM is 47.09 ± 2.52% (n = 42) from monthly measurements from 2021 to 2024 and VM is 39.35 ± 1.74 (n=42) from monthly measurements between 2021 and 2024. Physico-chemical analysis of several micropollutants is carried out once a month. An average representative sample from the dehydration process outlet is constituted using samples from each day of the week of the analysis. Details on each analytical method and the associated regulations are provided in the “Dataset_analyticalmethods_CakesSAV.xlsx”The following files are available:• Dataset _CakesSAV.xlsx• Dataset_analyticalmethods_CakesSAV.xlsxWastewater contains a wide range of biological and chemical markers related to human activity. The collection and analysis of these markers in the effluents (wastewater and sludge) allow to qualify the public health of the population and to evaluate the impact of the chemicals used in daily life on the environment.In line with these studies, the Innovation Department of SIAAP and its scientific partners (ISA and LEESU) have created an Observatory of the city with the objectives of:• Monitoring the long-term dynamics of known and/or potential pollutants according to French regulations.• Contributing to studies aimed at a better understanding of anthropogenic activities.• Structuring and centralizing data (wastewater and end-of-treatment sludge), ensuring their storage for 10 years.• Providing technical and scientific knowledge by publishing every two years the data generated by the Observatory of the city via the open platform Zenodo

Mode of delivery for confirmed macrosomia: a real-life multicentric observational study

International audienceNo abstract availabl

Systematic analysis of snRNA genes reveals frequent RNU2-2 variants in dominant and recessive developmental and epileptic encephalopathies

International audienceVariants in spliceosomal small nuclear RNA (snRNA) genes RNU4-2 (ReNU syndrome), RNU5B-1 , and RNU2-2 have recently been linked to dominant neurodevelopmental disorders (NDDs), revealing a major, previously overlooked role for noncoding snRNAs in human disease. Here, we systematically analysed 200 potentially functional snRNA genes in a French cohort comprising 26,911 individuals with rare disorders and through international collaborations. We identify de novo and biallelic variants in RNU2-2 associated with both dominant and recessive NDDs in 126 individuals from 108 unrelated families. Recessive RNU2-2 NDD is at least twice as frequent as the dominant NDD caused by n.4G&gt;A and n.35A&gt;G, and often arises from a de novo variant in trans with an inherited allele, reflecting the high mutability of snRNA genes. Dominant and recessive RNU2-2 -NDDs share overlapping clinical features with frequent epilepsy. Blood transcriptomics and DNA methylation analyses revealed subtle, variant-specific effects on splicing and episignatures. Our findings support a gradient-of-impact model and a continuum between dominant and recessive inheritance, establishing RNU2-2 variants as a frequent cause of NDDs, nearly as prevalent as ReNU syndrome

« Comme tu me vois » : Spatialités et mise en récits de la grossophobie ordinaire

International audienceEn 2022 une somme de recherches sur la grossophobie est proposée sous forme de traduction scénique par la compagnie Oxalis. Partant de cette expérience, et entremêlé d'éléments biographiques, dramaturgiques et académiques, cet article interroge la scène comme espace d'expression des expériences et des spatialités de l'obésité ainsi que de la grossophobie. Plus précisément, cet article mettra l'accent sur les espaces de santé, ceux de l'intime et ceux de la discrimination, en prenant appui sur huit productions actuelles autour de cette thématique. Que nous dis le théâtre des espaces de la grossophobie ? Comment traduire les expériences et les spatialités de l'obésité sur scène ? Quelles sont les dispositifs qui contribuent à cette nouvelle visibilité non seulement thématique mais également scénique ?</div