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Fructose malabsorption induces dysbiosis and increases anxiety in male human and animal models
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La réaction thiol-ène "Click" pour la synthèse de dérivés thioether et thioester biomoleculaires
No full textInternational audienceOver the past century, the radical thiol-ene reaction has demonstrated great value for the controlled synthesis of polymers and functionalised materials and for biomolecule conjugation. The free radical aspect offers many advantages, the three most prominent being water compatibility, a metal-free protocol (useful for the development of new therapeutic bioconjugates), and a biorthogonal mode of action. This chapter will cover recent developments in the use of the free radical thiol-ene 'click' reaction for the synthesis and the modification of biomolecules, bioconjugates and biomaterials. Applications in peptide and protein science are also discussed, including major contributions to the synthesis of glycopeptides and lipopeptides as well as peptide stapling and cyclisation. The various synthetic strategies towards thiosugars, glycoconjugates and glycoclusters are also highlighted with a focus on the regio-and stereoselectivity of the process. An overview of the thiol-ene mediated crosslinking strategy for the development of hydrogel biomaterials is also included, which demonstrates the diversity and versatility of the reaction in a biomolecular context
Large-scale radio bubbles around the black hole transient V4641 Sgr
No full textInternational audienceBlack holes (BHs) in microquasars can launch powerful relativistic jets that have the capacity to travel up to several parsecs from the compact object and interact with the interstellar medium. Recently, the detection of large-scale very-high-energy (VHE) gamma-ray emission around the black hole transient V4641 Sgr and other BH-jet systems suggested that jets from microquasars may play an important role in the production of galactic cosmic rays. V4641 Sgr is known for its superluminal radio jet discovered in 1999, but no radio counterpart of a large-scale jet has been observed. The goal of this work is to search for a radio counterpart of the extended VHE source. We observed V4641 Sgr with the MeerKAT radio telescope at the L and UHF bands and produced deep maps of the field using high dynamic range techniques. We report the discovery of a large-scale (35 pc), bow-tie-shaped, diffuse, radio structure around V4641 Sgr, with similar angular size to the extended X-ray emission discovered by XRISM. However, it is not spatially coincident with the extended VHE emission. After discussing the association of the structure with V4641 Sgr, we investigate the nature of the emission mechanism. We suggest that the bow-tie structure arose from the long-term action of large-scale jets or disk winds from V4641 Sgr. If the emission mechanism is of synchrotron origin, the radio/X-ray extended structure implies acceleration of electrons up to more than 100 TeV as far as tens of parsecs from the black hole
Baryon Acoustic Oscillations from the C IV Forest with DESI DR2
No full textInternational audienceWe present a measurement of Baryon Acoustic Oscillations (BAO) in the cross-correlation of triply ionized carbon C IV absorption with the positions of quasars (QSO) and Emission Line Galaxies (ELG). We use quasars and ELGs from the second data release (DR2) of the Dark Energy Spectroscopic Instrument (DESI) survey. Our data sample consists of 2.5 million quasars, 3.1 million ELGs, and the C IV absorption is measured along the line of sight of 1.5 million high redshift quasars with . We measure the isotropic BAO signal at 4.2 for the CIVQSO cross-correlation. This translates into a 3.0% precision measurement of the ratio of the isotropic distance scale, , and the sound horizon at the drag epoch, , with . We make the first detection of the BAO feature in the CIVELG cross-correlation at a significance of 2.5 and find
Cosmoglobe DR2. V. Spatial correlations between thermal dust and ionized carbon emission in Planck HFI and COBE-DIRBE
No full textInternational audienceWe fit five tracers of thermal dust emission to ten Planck HFI and COBE-DIRBE frequency maps between 353 GHz and 25 THz, aiming to map the relative importance of each physical host environment as a function of frequency and position on the sky. Four of these correspond to classic thermal dust tracers, namely H i (HI4PI), CO (Dame et al. 2001a), Hα (WHAM, Haffner et al. (2003a, 2016)), and dust extinction (Gaia; Edenhofer et al. 2024), while the fifth is ionized carbon (C ii) emission as observed by COBE- FIRAS. We jointly fit these five templates to each frequency channel through standard multi-variate linear regression. At frequencies higher than 1 THz, we find that the dominant tracer is in fact C ii, and above 10 THz this component accounts for almost the entire fitted signal; at frequencies below 1 THz, its importance is second only to H i. We further find that all five components are well described by a modified blackbody spectral energy density (SED) up to some component-dependent maximum frequency ranging between 1 and 5 THz. In this interpretation, the C ii-correlated component is the hottest among all five, with an effective temperature of about 25 K. The Hα component has a temperature of 18 K, and, unlike the other four, is observed in absorption rather than emission. Despite the simplicity of this model, which relies only on external templates coupled to spatially isotropic SEDs, we find that it captures 98 % of the full signal root mean squared (RMS) below 1 THz. This high efficiency suggests that spatial variations in the thermal dust SED, as for instance reported by Planck and other experiments, may be more economically modelled on large angular scales in terms of a spatial mixing of individually isotropic physical components
Transgenerational response to the ingestion of an endocrine disruptor: phenotypic, genetic, and epigenetic analyses in quail
No full textInternational audienceEpigenetic mechanisms such as DNA methylation can mediate the effect of the environment on an individual's phenotypes. While parental environments have also been shown to affect offspring phenotypes in several livestock species, evidence for transgenerational inheritance of environmentally induced epigenetic marks remains debated.This study aimed to assess the potential transgenerational inheritance of an environmental effect via epigenetic modifications in Japanese quails (Coturnix japonica). We investigated whether an initial dietary exposure to genistein - a natural phytoestrogen found in soybeans - could induce lasting phenotypic and epigenetic changes in subsequent generations.To disentangle genetic from epigenetic effects, we designed a balanced “mirror-crossing” scheme based on 20 founder families. In each family, two sisters were mated to the same male: one received a 30-day genistein supplementation (epi+ line), while the other was kept as a control, without genistein (epi– line). Their offspring were mated within each 'epiline' for three generations (G0–G2), ensuring a balanced representation of each genetic background in both epilines. Phenotypic data (body and tissue weights, egg production, and behavioral traits) were collected across all generations. DNA methylation profiles and genotypes were obtained from Reduced Representation Bisulfite Sequencing of 1,344 individual blood samples using BISCUIT, which allows jointly methylation and SNP calling. Differential methylation analysis was performed using the DSS package. Methylation heritability and methylation QTLs (metQTLs) were assessed with GCTA.Significant differences between epilines were detected for body weight. Epi+ females were consistently heavier than epi– controls at all ages, with the difference increasing across generations (up to +14 g in G2). A similar, though delayed, pattern was observed in males, becoming significant in G2 (+9 g at slaughter). Other traits, including reproduction and behavior, were not significantly affected. The proportion of phenotypic variance explained by the epiline increased over generations, suggesting either a genetic drift or non-genetic inherited effects.Methylation calling yielded 448,673 CpG sites in 1,267 individuals (mean coverage 34×). Among 111,168 variable CpGs (SD > 0.05), 22 and 72 were differentially methylated between epilines in G1 and G2, respectively, while no significant differences were detected in G0. A large number of CpGs showed significant sex × epiline interactions. The mean methylation heritability (h² = 0.24) supported moderate genetic control of methylation levels, with a high variability between CpGs.Ongoing analyses will contribute to a better understanding of the molecular mechanisms and biological significance of non-genetic inheritance in avian models.This project is funded by the European Union’s Horizon 2020 program GEroNIMO N°101000236, part of EuroFAANG (https://eurofaang.eu)
How Dry Is Dry? Radiolysis Reveals Hidden Water in Cementitious Materials
No full textInternational audienceAssessing whether cementitious materials are truly free of adsorbed water after drying remains experimentally challenging, yet residual water can strongly bias measurements of radiolytic molecular hydrogen production. Here, we use radiolytic H2 generation as a sensitive probe to quantify trace residual water and evaluate the efficiency of common desorption protocols. Non-porous model hydrates (portlandite and tobermorite) were subjected to freezedrying, solvent exchange, or thermal treatment under vacuum, then irradiated with accelerated electrons and their H2 yields measured. The results reveal clear differences between methods and minerals. Freeze-drying systematically left detectable surface-adsorbed water, while solvent exchange showed mineral-dependent limitations. Thermal vacuum treatment was the most effective, although complete desorption required harsher conditions than typically applied to cementitious materials. These findings establish radiolysis as a practical tool for detecting residual water and benchmarking drying procedures in cement-based systems
Strengthening temporal action segmentation through diffusion models
No full textInternational audienceThis paper addresses the task of temporal action segmentation and presents a joint approach that combines low-level and high-level video analysis techniques. Our approach introduces the usage of diffusion models to enhance the quality and accuracy of temporal action segmentation. This paper introduces a new method to segment actions in videos over time. We blend basic and advanced video analysis methods, using the diffusion technique from denoising to make our results more accurate. By combining text information with visual features from different levels of a video, we create a multi-stage process that generates diverse features using the denoising network and improves the quality of our visual data. By leveraging the interplay between denoising and high-level segmentation tasks, our approach offers several advantages. These include the incorporation of a feedback loop for iterative refinement, improved overall performance through synergy between the two tasks, enhanced robustness and generalization. Our approach achieves reliable accuracies of 83.4%, 90.7% and 77.6% on the Georgia Tech Egocentric Activities, 50 Salads and Breakfast datasets respectively
Decentralized multi-agent multi-armed bandits for smart electric vehicles charging
No full textInternational audienceSmart charging of electrical vehicles can help in avoiding congestion and peak load demands in an electrical distribution network. On the consumer's side, the advantage lies in minimizing the daily charging cost. He may also benefit from cheap photovoltaic electricity from local sources and therefore reduce his environmental impact. However, this cheaper electricity is variable and uncertain. In many research works, this has been formulated and solved as a centralized or hierarchical optimization problem. However, such systems may suffer from lack of scalability, single point of failures, and privacy breaches. We propose a fully decentralized and fair multi-agent system combined with reinforcement learning called "Decentralised multi-armed bandit (2-armed bandit) based on Thompson sampling"(D-MAB2AB-TS) to control the charging of electrical vehicles under uncertainties. The problem under consideration is formulated as a two-armed bandit (charging or not) for each instant. The proposed algorithm, based on Thompson Sampling, takes into account the uncertainties in the choice of arms combination of other players. The proposed algorithm finds the best combination of arms to play with a computational complexity O(m) linear with the number of arms. The suggested system is also model-free, as it does not assume the model of the environment to be perfectly known, which is a common assumption in many of the existing centralized optimization strategies for smart charging.</div
Transcriptomic profiling reveals similarities between equine IVF and ICSI embryos
No full textInternational audienceIn vitro production of equine embryos has been performed using intracytoplasmic sperm injection (ICSI) for the last two decades. Since 2022, a repeatable protocol for conventional in vitro fertilization (IVF) provides a successful alternative. However, little is known about the influence of the fertilization method on embryo quality and the transcriptomic profile. In this study, we aimed to examine differentially expressed genes (DEGs) between ICSI and IVF embryos in the horse. Therefore, ten equine sibling blastocysts, produced in vitro by either ICSI or IVF from three different mares, were subjected to Full-Length Single-Cell RNA-Sequencing (FLASH-sequencing). As such, 11,518 genes were identified, with no DEGs between ICSI and IVF embryos. Cleavage rates, calculated on collected COCs, of IVF zygotes (55.0 %) were similar to those of ICSI zygotes (51.9 %; P = 0.74), but blastocyst rates were higher following ICSI (37.0 % vs 22.5 % calculated on collected COCs and 71.4 % vs 40.9 % calculated on cleaved zygotes; P = 0.04 and 0.004, respectively). The average day of blastocyst development did not differ (P = 0.55). In conclusion, gene expression was similar for the two fertilization techniques, supporting the safety of equine IVF for further clinical studies. Overall, the horse provides a valuable model to study longterm effects of assisted reproductive technologies with potential extrapolation to human medicine