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La fonction didactique du Psautier
No full textInternational audienceThis article focuses on the didactic function of the Masoretic Psalter in the Second Temple period. It shows that an approach to the psalms based on the “family resemblance” model, combined with the identification of prototypical texts, makes it possible to understand the didactic typicity of the psalms of the Second Temple period. It exposes that this functional typicity may have been modified in some cases, in particular to serve partisan debates or various polemics. Finally, it examines the inclusion of the Psalter in the literature of advice and the editorial process that gave it a didactic function
Preface to Fields, Gravity, Strings and Beyond: In Memory of Stanley Deser
No full textInternational audienceThis is a preface to Fields, Gravity, Strings and Beyond, a special issue collection of articles published in J. Phys. A in memory of Stanley Deser
Influenza vaccine effectiveness and genetic diversity: insights from end-of-season community surveillance, France, 2024-2025
No full textInternational audienceInfluenza 2024-2025 season in France was characterized by prolonged duration, unusual co-circulation of all three viruses (A(H1N1)pdm09, A(H3N2), B/Victoria) with several subclades, and substantial healthcare impact. We aimed to investigate the impact of influenza genetic diversity on vaccine effectiveness (VE).A test-negative design study was conducted to estimate VE in a large cohort from the RELAB network of community-based laboratories (n = 77,704 patients). A subset of sequenced samples (n = 2,119 patients) allowed VE estimation for several clades and subclades as well as comparison of subclade distribution by vaccination status.Vaccine coverage was 45% in patients aged 65 years and older (65+). VE based on PCR-confirmed infections was 44% (95% CI: 41-48%) and lower in 65+ individuals, at 25% (95% CI:18-31%) especially for type A virus (23%; 95% CI: 13-32%) compared to type B virus (57%; 95% CI: 35-72%).Sequencing-confirmed VE among individuals vaccinated 15 days to 3 months prior testing, was 41% (95% CI: 14-60%) for A(H1N1)pdm09 and 47% (95% CI: 21-64%) for its main subclade 5a.2a(C.1.9.3); A(H3N2) estimate was 30% (95% CI:5-48%) and 31% (95% CI:4-50%) for 2a.3a.1(J.2) sublclade. The emerging A(H1N1)pdm09 5a.2a.1 (D.3) subclade was significantly more frequent among vaccinated individuals compared to unvaccinated.The low vaccine coverage combined with the notably low effectiveness against A(H3N2) and for type A in elderly may have contributed to the high influenza activity this season. The emergence of A(H1N1)pdm09 5a.2a.1 (D.3) raises uncertainty and requires surveillance.</p
The Metabolically Resistant Apelin-17 Analogue LIT01-196 Reduces Cardiac Dysfunction and Remodelling in Heart Failure After Myocardial Infarction
No full textInternational audienceBackground: To protect patients after myocardial infarction (MI) and preserve cardiac function, the development of new therapeutics remains an important issue. Apelin, a neuro-vasoactive peptide, increases aqueous diuresis and cardiac contractility while reducing vascular resistance. However, its in vivo half-life is very short. We therefore developed a metabolically resistant apelin-17 analogue, LIT01-196 and investigated its effects on cardiac function and remodelling in a murine MI model.Methods: The selectivity of LIT01-196 toward the apelin receptor was checked in vitro. Its in vivo half-life was assessed in male Swiss mice using radioimmunoassay. After permanent coronary artery ligation to induce MI, mice received subcutaneous administration of LIT01-196 (MI + LIT01-196, 9 mg/kg/d) or saline (MI + vehicle) for 4 weeks. Left ventricular (LV) function was assessed using echocardiography and Millar (Houston, TX) catheter, vascular density using immunofluorescence, and cardiac fibrosis using Sirius red staining. Real-time quantitative PCR was used to measure mRNA expression of heart failure (HF) fibrosis biomarkers and sarco/endoplasmic reticulum Ca2+-ATPase-2.Results: The in vivo half-life of LIT01-196, a specific and selective apelin receptor agonist, was 2.5 hours. MI + LIT01-196 showed significantly improved LV function, reduced HF biomarkers, and enhanced cardiac contractility and sarco/endoplasmic reticulum Ca2+-ATPase-2 expression compared with MI + vehicle. LIT01-196 treatment almost doubled cardiac vascular density and maintained LV wall thickness post MI. It also significantly reduced cardiac fibrosis and fibrosis biomarkers, without decreasing arterial blood pressure.Conclusions: Chronic LIT01-196 treatment post MI improves LV function without decreasing blood pressure, increases cardiac vascular density, and reduces cardiac remodelling. This suggests that apelin receptor activation by LIT01-196 might constitute an original pharmacological approach for HF treatment after MI.Contexte : Pour protéger les patients après un infarctus du myocarde (IM) et préserver la fonction cardiaque, le développement de nouvelles thérapeutiques reste une question importante. L’apéline, un peptide neuro-vasoactif, augmente la diurèse aqueuse et la contractilité cardiaque tout en réduisant la résistance vasculaire. Cependant, sa demi-vie in vivo est très courte. Nous avons donc développé un analogue de l’apeline-17 résistant au métabolisme, le LIT01-196, et nous avons étudie ses effets sur la fonction et le remodelage cardiaques dans un modèle murin d’IM. Méthodes : La sélectivité du LIT01-196 vis-à-vis du récepteur de l’apéline a été vérifiée in vitro. Sa demi-vie in vivo a été évaluée chez des souris mâles de type Swiss à l’aide d’un dosage radioimmunologique. Après ligature permanente de l’artère coronaire pour induire un IM, les souris ont reçu une administration sous-cutanée de LIT01-196 (IM þ LIT01-196, 9 mg/kg/j) ou de solution saline (IM þ vehicule) pendant 4 semaines. La fonction ventriculaire gauche (VG) a été évaluée par échocardiographie et cathéter Millar (Houston, TX), la densite vasculaire par immunofluorescence et la fibrose cardiaque par coloration au rouge Sirius. La PCR quantitative en temps réel a été utilisée pour mesurer l’expression de l’ARNm des biomarqueurs de la fibrose liée à l’insuffisance cardiaque (IC) et de la Ca2þ-ATPase-2 du réticulum sarco-endoplasmique.Résultats : La demi-vie in vivo du LIT01-196, un agoniste spécifique et sélectif du récepteur de l’apéline, était de 2,5 heures. Le groupe expérimental IM þ LIT01-196 a montre une amélioration significative de la fonction du VG, une réduction des biomarqueurs de l’IC et une amélioration de la contractilité cardiaque et de l’expression de la Ca2þATPase-2 du réticulum sarco/endoplasmique, par rapport au groupe IM + véhicule. Le traitement par LIT01-196 a presque double la densité vasculaire cardiaque et maintenu l’épaisseur de la paroi du VG après l’IM. Il a également réduit de manière significative la fibrose cardiaque et les biomarqueurs de la fibrose, sans diminuer la pression artérielle.Conclusions : Le traitement chronique par le LIT01-196 après un IM améliore la fonction VG sans diminuer la pression artérielle, augmente la densité vasculaire cardiaque et réduit le remodelage cardiaque. Cela suggère que l’activation du récepteur de l’apéline par le LIT01196 pourrait constituer une approche pharmacologique originale pour le traitement de l’IC après un IM
(Not-So-) Radicals: Debating Moderate Salafism in Russia
No full textInternational audienceIn the context of traditionalist tendencies in the Russian religious space in 2000-2010, Salafism became the object of intense discursive production. Interpretations range from explicit criticism to the identification of its modernizing potential. The article analyzes various approaches at both federal and local levels, using the regions of Dagestan and Tatarstan as examples. Despite the politically polarized character of the discussion, these actors share important fundamental assumptions. These trends are compared with the French debate by Olivier Roy and Gilles Kepel and are analyzed in relation to secularization theories
Altlussheim et Wolfsheim : les objets sassanides dans les tombes de chefs militaires de l’époque des Grandes Migrations.
No full textInternational audienc
How Different Uses of AI Shape Labor Demand: Evidence from France
No full textInternational audienceUsing French firm-level data on AI adoption from 2017-2020, we find that, first, firms adopting AI are larger and more productive and skill intensive. Second, difference-in-difference estimates reveal an increase in firm-level employment and sales after AI adoption, suggesting that the induced productivity gains allow firms to grow and outweigh potential displacement effects. Third, occupations classified in recent work as substitutable with AI expand. Fourth, AI usage is a relevant dimension of heterogeneity in the labor demand response: We find positive employment growth for certain uses (e.g., information and communications technology security) and negative for others (e.g., administrative processes)
Character recognition in Byzantine seals with deep neural networks
No full textInternational audienceSeals are small coin-shaped artifacts, mostly made of lead, held with strings to seal letters. This work presents the first attempt towards automatic reading of inscribed text on Byzantine seal images. Byzantine seals are generally decorated with iconography on the obverse side and Greek text on the reverse side. Text may include the sender's name, position in the Byzantine aristocracy, and elements of prayers. Both text and iconography are precious literary sources that wait to be exploited electronically, so the development of computerized systems for interpreting seals images is of paramount importance. This work's contribution is hence a deep, two-stages, character reading pipeline for transcribing Byzantine seal images. A first deep convolutional neural network (CNN) detects characters in the seal (character localization). A second convolutional network reads the localized characters (character classification). Finally, a diplomatic transcription of the seal is provided by post-processing the two network outputs. We provide an experimental evaluation of each CNN in isolation and both CNNs in combination. All performances are evaluated by cross-validation. Character localization achieves a mean average precision (mAP) greater than 0.9 at the intersection of union threshold of 0.5. Classification of characters achieves an accuracy greater than 0.92. Such performance compares favorably to similar tasks such as the recognition of inscribed characters on ancient coins. At transcription level, we provide novel performance results in terms of Character Error Rate. This is novel for seal images and differs from results on isolated character recognition
Sequence, duration, rate of deformation and paleostress evolution during fold development: Insights from fractures, calcite twins and U-Pb calcite geochronology in the Mirabeau anticline (SE France).
No full textInternational audienceThe timing and duration of folding events have traditionally been constrained by the dating of syn-tectonic layers that record fold growth and limb rotation. However, recent advances demonstrate that absolute U-Pb geochronology on well-characterized distributed mesoscale structures such as fractures and stylolites allows the reconstruction of a detailed deformation timeline spanning the entire folding event even when growth strata are absent. In this study, we integrate structural analysis with calcite twin paleopiezometry, inversion of fault slip data, and U-Pb dating of syn-tectonic calcite mineralizations from faults, veins and stylolite-related jogs to refine the classical fold-fracture model and provide a more comprehensive view and precise timing of brittle deformation and stress evolution during folding using the example of the Mirabeau anticline (Provence, SE France). The onset of layer-parallel shortening (LPS) has been precisely constrained for the first time using absolute U-Pb dating of a calcite-filled jog associated with a bedding-parallel stylolite (BPS) and the earliest striated reverse faults associated with Pyrenean shortening. The brittle deformation associated with the folding event of the Mirabeau anticline is recorded continuously between similar to 50 Ma and similar to 37 Ma, with layer parallel shortening (LPS) lasting similar to 5 My, fold growth lasting similar to 3 My, and late-stage fold tightening (LSFT) lasting similar to 5 My. Combining our shortening estimate derived from and balanced cross-section with absolute ages of fold growth, we estimate a Pyrenean shortening rate of approximately 0.6 mm/yr at Mirabeau. Our results further place important new time constraints on the sequence of structural development through the Provence fold-and-thrust belt, and support a forelandward propagation of Pyrenean deformation across Provence. The integration of fracture sequence analysis, calcite twin inversion and striated fault inversion provides insights into the tectonic evolution of the Mirabeau area: (1) pre-Pyrenean alternating NNE-SSW and WNW-ESE extension between similar to 112 and similar to 90 Ma, likely related to the Durance uplift event (2) Eocene Pyrenean-Proven & ccedil;al shortening dominated by a N-S to NE-SW horizontal sigma(1) under alternating compressional and strike-slip stress regimes, (3) Oligocene E-W extension associated with the West European rifting event, and (4) a minor compressional stress regime with NW-SE to NNW-SSE oriented sigma 1 attributed to Miocene Alpine shortening
Les astrocytes au cœur du sommeil : des gènes à la dynamique des réseaux
No full textInternational audienceAstrocytes have transcended their role from mere structural scaffolds to pivotal regulators of neural circuitry and sleep–wake dynamics. The strategic proximity of their fine processes to blood vessels and synapses positions them as key players in neurobiology, contributing to the tripartite synapse concept. Gap-junction proteins also enable astrocytes to form an extensive network interacting with neuronal assemblies to influence sleep physiology. Recent advances in genetic engineering, neuroimaging and molecular biology have deepened our understanding of astrocytic functions. This review highlights the different mechanisms by which astrocytes regulate sleep, notably through transcriptomic and morphological changes, as well as gliotransmission, whereby intracellular calcium (Ca 2+ ) dynamics plays a significant role in modulating the sleep–wake cycle. In vivo optogenetic stimulation of astrocytes indeed induces ATP release, which is subsequently degraded into adenosine, modulating neuronal excitability in sleep–wake regulatory brain regions. Astrocytes also participate in synaptic plasticity, potentially modulating sleep-associated downscaling, a process essential for memory consolidation and preventing synaptic saturation. Although astrocytic involvement in synaptic maintenance is well supported, the precise molecular mechanisms linking these processes to sleep regulation remain to be elucidated. By highlighting astrocytes' multiple roles in sleep physiology, these insights deepen our understanding of sleep mechanisms and pave the way for improving sleep quality.Traditionnellement considérés comme de simples éléments de soutien du système nerveux central, les astrocytes sont désormais reconnus comme des régulateurs clés des circuits neuronaux et de la dynamique veille–sommeil. Leur proximité stratégique avec les vaisseaux sanguins et les synapses, via leurs prolongements fins, en fait des acteurs majeurs de la neurobiologie, contribuant pleinement au concept de synapse tripartite. Grâce aux protéines des jonctions communicantes, les astrocytes forment un vaste réseau interagissant avec les ensembles neuronaux pour moduler la physiologie du sommeil. Les avancées récentes en génétique, neuroimagerie et biologie moléculaire ont considérablement approfondi notre compréhension de leurs fonctions.Cette revue explore les mécanismes par lesquels les astrocytes influencent le sommeil, notamment par des modifications transcriptomiques et morphologiques, ainsi que par la gliotransmission. Dans ce cadre, la dynamique du calcium intracellulaire (Ca²⁺) joue un rôle central dans la modulation du cycle veille–sommeil. En effet, la stimulation optogénétique des astrocytes in vivo induit la libération d’ATP, rapidement dégradé en adénosine, ce qui module l’excitabilité neuronale dans les régions cérébrales impliquées dans la régulation du sommeil.Les astrocytes participent également à la plasticité synaptique, notamment à travers la modulation du processus de réduction synaptique associé au sommeil, essentiel à la consolidation de la mémoire et à la prévention de la saturation synaptique. Bien que leur rôle dans le maintien synaptique soit bien établi, les mécanismes moléculaires précis liant ces fonctions à la régulation du sommeil demeurent à élucider. En soulignant les multiples rôles des astrocytes dans la physiologie du sommeil, ces travaux approfondissent notre compréhension des mécanismes du sommeil et ouvrent de nouvelles perspectives pour en améliorer la qualité