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Imaging two-body correlations in atomic nuclei via low- and high-energy processes
No full textInternational audienceCharacterizing the correlated behavior of nucleons inside atomic nuclei constitutes a long-standing challenge, both experimentally and theoretically. It has recently been understood that two-particle correlations in the azimuthal distribution of final hadrons emitted in ultra-relativistic ultra-central ion-ion collisions can be used to quantify ground-state two-body correlations. Performing systematic ab initio nuclear structure calculations of light nuclei, we demonstrate that such an observable does provide a meaningful imaging of nuclear ground states, naturally leading to a robust interpretation of the various categories of two-nucleon correlations at play. This is at variance with the low-energy approach relying on Kumar operators whose traditional interpretation in terms of deformation parameters is shown to be inoperative. A future interesting development will consist of targeting specific three-particle correlations to isolate three-nucleon correlations in which additional nuclear structure information of interest leave their fingerprint
Combined “omics” and physiological approaches highlight the roles of the GABA shunt and mitochondria-related functions in rice seed longevity
No full textInternational audienceIn the context of global warming, the ability of seeds to withstand higher temperatures and humidity during dry storage is critical to maintain food production. Seed longevity, also referred to as storability, is therefore an essential trait. As a major staple crop, rice (Oryza sativa L.) has been widely studied to identify the genetic determinants of seed longevity, primarily through QTL mapping and molecular analyses. However, integrated multi-omics data remain limited, especially compared to advances made for other seed physiological features (e.g., dry quiescence, germination). This study investigates the molecular determinants of rice seed longevity under varying storage conditions using controlled deterioration treatments (CDTs) at 25 °C (no deterioration), 40 °C (reduction of germination speed and uniformity) and 45 °C (loss of germinative capacity) under high relative humidity. Through physiological characterizationand multi-omics analyses, we identified key metabolic pathways and genetic factors associated with seed aging. By integrating transcriptomic, proteomic, and metabolomic data, we pinpointed specific pathways critical to seed viability loss. CDTs revealed that only a small number of genes and proteins are significantly affected. In particular, our results highlight a major impact of CDTs on the GABA shunt and mitochondrial factors as the DEAD-box ATP-dependent RNA helicase 9. Altogether, this work opens the way for in-depth functional studies on a small number of mitochondria-related genes involved in rice seed longevity
Juvenile-onset mixed connective tissue disease: A multicenter retrospective cohort study
No full textInternational audienceObjectives: Juvenile-onset mixed connective tissue disease (jMCTD) accounts for 7-23 % of MCTD cases but remains poorly described. We aimed to characterize clinical features, treatments, and outcomes of patients with jMCTD, and compare them to adult-onset MCTD (aMCTD) patients. Methods: We conducted a multicenter, retrospective, case-control study within the French MCTD cohort. Each jMCTD patient was compared to 3 matched aMCTD patients. Results: Forty-seven jMCTD patients (93.6 % girls; median age at onset 14 [11-16] years) were included. Forty-four (93.6 %) jMCTD patients fulfilled either Sharp or Kasukawa diagnostic criteria. None of them met other diagnostic criteria without fulfilling Sharp or Kasukawa criteria. At diagnosis, jMCTD patients' main manifestations were Raynaud's phenomenon, arthralgia, and myalgia. jMCTD patients had less frequently puffy fingers than aMCTD (p < 0.0001). Cumulatively, jMCTD patients mainly received glucocorticoids (80.9 %), hydroxychloroquine (95.7 %) and immunosuppressants (93.6 %). They received a higher initial dose of glucocorticoids (30 [20-60] mg/day vs. 15 [10-35] mg/day, p = 0.02), and significantly more frequently methotrexate (Methotrexate) and rituximab (p = 0.01) over time compared to aMCTD. After a median follow-up of 9.8 [6.6-16.2] years, 29 (61.7 %) jMCTD patients were in remission (vs. 62 (44.0 %) aMCTD; p < 0.05), 36 % had progressed to another CTD (vs. 30.5 % aMCTD; p = 0.5), mainly systemic lupus erythematosus, 11 (23.4 %) had developed interstitial lung disease, 2 (4.3 %) pulmonary arterial hypertension, and 1 (2.1 %) died. Conclusions: jMCTD share the same clinical characteristics as aMCTD patients, but less frequently have puffy fingers. Outcomes appear more favorable in jMCTD than aMCTD, with higher remission rates, albeit at the cost of more intensive treatment
Thiamine and folate immunolocalization in germinating lentil seeds: A microstructural investigation
No full textInternational audienceHighlights: • Thiamine and folate act as cofactors in many human and vegetal metabolic pathways. • Germination is an effective process for increasing the thiamine and folate content. • Immunohistochemistry can localize the storage area of thiamine and folate. • Image analysis revealed heterogeneous distribution of vitamers in the pulse. • We obtained both quantitative and qualitative information on the metabolite content.Abstract: Thiamine and folate are vital for both human and plant health, serving as cofactors in various metabolic processes. Thiamine is essential for carbohydrate and amino acid metabolism, while folate is crucial for DNA synthesis and the methyl cycle. Germination has been proven to increase thiamine and folate levels in lentils. While high-performance liquid chromatography (HPLC) is effective for measuring vitamin content, it does not reveal the spatial distribution of these compounds within seeds during germination. To address this, immunohistochemistry (IHC) was used in this study to localize and quantify thiamine and folate in dry, soaked, and germinated lentils. The analysis revealed that these vitamins are distributed unevenly across cotyledons and cells. In dry seeds, thiamine and folate were concentrated around starch granules, but in soaked and germinated seeds, they were dispersed throughout the cytoplasm and near protein bodies. This innovative method provided both quantitative and qualitative insights into how germination affects vitamin distribution, enhancing our understanding of seed metabolism and the behavior of vitamins during food processing
Compte rendu du Colloque sur la journée des données des Plateformes d'Alliance Sorbonne Université: Enjeux et outils de gestion des données des Plateformes
No full textInternational audienceThis document summarizes and expands on certain concepts and tools presented during the “Alliance Sorbonne University Platform Data Day” on the management of research data from platforms, the recordings of which are available at the following link: https://d-videothequepeertube.sorbonne-universite.fr/c/donnees_plateformes_asu/videos. The program for the day is presented at the end of the document. The aim was to address concepts found in data management plans (DMPs) and adapt them to the platform level. In this document, you will find a definition of platforms and their roles, and a presentation on the scientific issues related to the platform DMP, an entity that plays an active role in the research ecosystem, contributing to the reuse and preservation of research data. Another presentation outlines the complex legal context of platforms, followed by a presentation on the storage, backup, and archiving of platform data. Several tools that assist in research data management are discussed: Collec-Science for samples, the CLE electronic laboratory notebook project, OpenIris for documents and equipment, and the IFB instance of DSW to assist in the drafting of PGDs.Ce document synthétise et développe certaines notions et certains outils, présentés à l'occasion de la « journée des données des plateformes d'Alliance Sorbonne Université », sur la gestion des données de la recherche des plateformes dont les enregistrements sont disponibles sur le lien suivant https://d-videothequepeertube.sorbonne-universite.fr/c/donnees_plateformes_asu/videos. Le programme de cette journée est présenté en fin de document. L'objectif de cette journée était d'aborder des notions présentes dans les plans de gestion de données (PGD) et de les adapter au niveau des plateformes. Dans ce document vous trouverez une définition des plateformes et de leurs rôles, et une présentation sur les enjeux scientifiques liés au PGD plateforme, entité actrice de l'écosystème de la recherche contribuant à la réutilisation et à la pérennisation des données de recherche. Une autre présentation restitue le cadre réglementaire complexe des plateformes, suivie d'une présentation sur le stockage, la sauvegarde et l'archivage des données des ces dernières. Quelques outils qui aident à la gestion des données de la recherche sont abordés : Collec-Science pour les échantillons, le projet CLE du cahier de laboratoire électronique, OpenIris pour les documents et les équipements, et l'instance IFB de DSW pour aider à la rédaction de PGD
A genetic variant of BAFF is associated with the risk of lymphoma in Sjögren disease
No full textInternational audienceObjective B-cell activating factor of the TNF family (BAFF) is involved in the pathogenesis of Sjögren's disease (SjD). A functional variant (BAFF-var) of BAFF gene (TNFSF13B), leading to increased level of BAFF has been described. The aim of this study was to investigate the association between BAFF-var and clinical phenotype and risk of SjD. MethodsA case-control study including cases from Paris Saclay and the Assessment of Systemic Signs and Evolution in Sjögren's syndrome (ASSESS) cohort and controls (blood donors from Etablissement Français du Sang [EFS]) was conducted. Genetic association analyses included only patients with European ancestry assessed by a principal component analysis using 24 ancestry-informative markers.ResultsWe included 770 cases (420 from Paris Saclay and 350 from ASSESS) and 786 controls from EFS. Among them, 666 cases and 721 controls were found of European ancestry. We found that BAFF-var was significantly associated with higher soluble BAFF (sBAFF) level (1392.7 vs 1107.0 pg/mL, P < .001), and with increased occurrence of lymphoma (13% in patients with SjD with BAFF-var vs 5.8% in patients with SjD with BAFF-WT (wild-type), P = .013). BAFF-var remained independently associated with lymphoma after adjustment for rheumatoid factor, sex, and cumulative European League Against Rheumatism Sjögren’s Syndrome Disease Activity Index (odds ratio [OR] 2.60, 95% CI: 1.14-5.47). By comparison with ancestry-matched controls, BAFF-var was also associated with SjD itself with a minor allele frequency of 0.061 in cases and 0.035 in controls (OR = 1.77, P = .0017).ConclusionsWe found an association between BAFF-var and sBAFF levels, occurrence of lymphoma as well as occurrence of SjD itself. This variant could be a new biomarker for lymphoma risk in SjD
Gouvernance portuaire et résilience : éclairages bibliométriques et retours d’experts sur le cas du Havre
No full textInternational audienceThe Covid-19 crisis, climate change, geopolitical conflicts, and changes in ship trade routes have generated unprecedented disruptions in fragmented and globalized maritime logistics chains. Port logistics, whose function is to move goods through logistics corridors, has faced challenges such as equipment shortages, lockdowns, and port closures. The objective of this research is to examine the relationships between the main stakeholders of port governance and how they can steer the system towards a more resilient configuration.E. Ostrom's IAD (Institutional Analysis and Development) framework appears as an interesting approach that can help advance the understanding at the system level of port governance by viewing it as an action situation, an infrastructure for processing physical and information flows that interacts with external infrastructures of a technical or human nature and natural infrastructures (the river).la crise du covid 19, le changement climatique, les conflits géopolitiques et le changement des itinéraires commerciaux des navires ont généré des perturbations sans précédent dans les chaines logistiques maritimes mondiales fragmentées et mondialisées.La logistique portuaire dont la fonction est de faire circuler la marchandise à travers des corridors logistiques a été confrontée à des défis tels que les pénuries d’équipements, le confinement et la fermeture des ports.L’objectif de cet article est d’apporter un éclairage intégré sur les dynamiques de gouvernance portuaire et de résilience, en mobilisant une analyse bibliométrique et une consultation d’experts.Le cadre d’analyse ADI d’E. Ostrom (2011) apparait comme une approche intéressante qui peut aider à faire progresser la compréhension au niveau du système de la gouvernance portuaire en l’envisageant comme une situation d’action, une infrastructure de traitement des flux physiques et informationnels qui interagit avec les infrastructures externes de nature technique ou humaine et les infrastructures naturelles (le fleuve)
Search for lepton-number-violating decays
No full textInternational audienceA search is performed for lepton-number-violating decays, using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 5.4 fb. No significant signal is observed, and upper limits are set on the branching fractions, and , at the 95% confidence level
Type I IFN autoantibodies underlie chikungunya live-attenuated vaccine encephalitis
No full textInternational audienceHuman autoantibodies neutralizing type I interferons (IFNs) have emerged as strong, common, and global determinants of a growing number of severe viral diseases, including hypoxemic viral pneumonia, arboviral encephalitis, and adverse reaction to the live-attenuated yellow fever virus (YFV) vaccine. Chikungunya virus (CHIKV) is a growing global health concern that the live-attenuated vaccine VLA1553 (IXCHIQ®) was developed to address. In 2025, five unrelated adults (aged 82 to 88) on the island of La Réunion (France) developed severe reactions postvaccination; two died. The three patients with encephalitis (aged 84 to 85), including one lethal case, had immunoglobulin G autoantibodies in the blood neutralizing high concentrations of both IFN-α and -ω on admission. An 82-y-old survived rhabdomyolysis without encephalitis, and an 88-y-old died during hospitalization following CHIKV infection despite late vaccination; both lacked autoantibodies against type I IFNs. Autoantibodies neutralizing type I IFNs underlie all three cases of live-attenuated CHIKV vaccine encephalitis studied. Individuals with autoantibodies neutralizing type I IFNs should not be inoculated with live-attenuated YFV and CHIKV vaccines
Cobalamin-mediated protection of Faecalibacterium duncaniae against oxidative stress: Insights from proteomic and membrane fatty acid profiles
No full textInternational audienceFaecalibacterium species are keystone commensals of the human gut, contributing to intestinal homeostasis, immune modulation, and epithelial health. However, their extreme sensitivity to oxygen and reactive oxygen species renders them highly vulnerable during inflammatory conditions, severely limiting their therapeutic application. Understanding the molecular mechanisms underlying their oxidative stress responses is therefore critical for harnessing these bacteria as next-generation probiotics to restore gut health. In this study, we investigated oxidative stress responses in Faecalibacterium duncaniae A2–165 using comprehensive proteomic and membrane fatty acid profiling. We demonstrated that increasing hydrogen peroxide (H₂O₂) concentrations extend the lag phase of growth and affect survival during the first hour of exposure, notably altering the redox potential. Exposure to H₂O₂ triggered a remodeling of the proteome, including detoxification systems, metal transporters, DNA repair systems, transcriptional regulators, and enzymes involved in cobalamin biosynthesis. Complementary RT-qPCR analyses revealed coordinated and time-dependent transcriptional activation of genes involved in oxidative stress response. Remarkably, cobalamin supplementation enhanced bacterial growth, mitigated H₂O₂-induced stress, and lowered superoxide levels in F. duncaniae, highlighting its direct antioxidant activity. By analyzing membrane fatty acid profiles, we showed that cobalamin preserves membrane fluidity, counteracting oxidative stress induced by H₂O₂ in F. duncaniae. These findings reveal the multifaceted strategies employed by F. duncaniae to withstand oxidative stress and provide a foundation for future efforts to optimize its production at industrial scales and its therapeutic potential as a next-generation probiotic