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An original approach combining biogeochemical signatures and a mixing model to discriminate spatial runoff-generating sources in a peri-urban catchment
No full textInternational audienceAbstract. Hydrograph separation using biogeochemical data is a commonly used method for the vertical decomposition of flow into surface, subsurface and groundwater contributions. However, its application to the spatial decomposition of flow remains limited, despite its potential to identify contributions linked to geological, pedological, and land use characteristics, as well as anthropogenic contaminant sources. In this study, a Bayesian mixing model was applied to the Ratier peri-urban sub-catchment of the OTHU Yzeron observatory. Eight runoff-generating sources were identified and sampled, including different land uses (e.g. forest, grassland, agricultural areas), a colluvium aquifer, and urban point discharges (e.g. sewer system, urban and road surface runoff). A wide range of biogeochemical parameters were analysed including classical (i.e., major chemical compounds, dissolved metals) and innovative tracers (i.e., characteristics of dissolved organic matter, microbial indicators). Streamwater samples collected under contrasting hydro-meteorological conditions revealed distinct source signatures and highly variable contributions, with wastewater dominating under dry weather and rapid surface runoff during summer storms. Using these results, we improved a previously designed perceptual hydrological model of the Ratier and Mercier catchments, at the hillslope scale, which highlighted the potential of spatial tracer-based decomposition in addition to classical vertical hydrological separation. More broadly, this study demonstrates the potential of such mixing model, using classical but also more innovative tracers, to provide insights for validating distributed hydrological models and to anticipate the influence of land use, urbanisation, and climate changes on runoff generation
Uncovering the molecular logic of cortical wiring between neuronal subtypes across development through ligand–receptor inference
No full textInternational audienceThe cerebral cortex comprises diverse excitatory and inhibitory neuron subtypes, each with distinct laminar positions and connectivity patterns. Yet, the molecular logic underlying their precise wiring remains poorly understood. To identify ligand-receptor (LR) interactions involved in cortical circuit assembly, we tracked gene expression dynamics in mice across major neuronal populations at 17 developmental stages using single-cell transcriptomics. This generated a comprehensive atlas of LR-mediated communication between excitatory and inhibitory neuron subtypes, capturing known and novel interactions. Notably, we identified NEOGENIN-1 as the principal receptor for CBLN4 during the perinatal period, mediating synapse formation between somatostatin-expressing interneurons and glutamatergic neurons. We also identified members of the cadherin superfamily as candidate regulators of perisomatic inhibition from parvalbumin-expressing basket cells onto deep and superficial excitatory neurons, exerting opposing effects on synapse formation. These findings suggest a context-dependent role for cadherins in synaptic specificity and underscore the power of single-cell transcriptomics for decoding the molecular mechanisms of cortical wiring.The mammalian cerebral cortex is a six-layered structure at the brain's surface that supports the most complex cognitive functions. These functions rely on highly orchestrated and evolutionarily conserved developmental processes that establish precise patterns of communication between two major classes of neurons: excitatory glutamatergic neurons (GlutNs) and inhibitory GABAergic neurons (GABANs). Both GlutNs and GABANs are further subdivided into numerous transcriptionally defined subtypes, a diversity largely revealed by singlecell RNA sequencing (scRNA-seq). Dozens of GlutN and GABAN subtypes have been identified 1-5 , each characterized by distinct morphological, electrophysiological, and molecular properties, preferential laminar localization, specific synaptic partners and selective targeting of subcellular compartments. This precise organization establishes the intricate cortical wiring that underpins cortical computation. Disruption of connectivity between even a single pair of neuron subtypes at a given developmental stage can impair circuit function and contribute to neurodevelopmental disorders 6 . Elucidating how subtype-specific connections are established and regulated is therefore essential for understanding both cortical development and disease.</div
BrGDGT-based palaeothermometer in drylands: the necessity to constrain aridity and salinity as confounding factors to ensure the robustness of calibrations
No full textInternational audiencePast temperature reconstructions offer valuable insights into the impact of climate change on the global climate-human-vegetation system. Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are recognized as effective temperature proxies, particularly in lakes and peatlands, where they are well preserved. However, their reliability as palaeothermometers can be compromised by factors beyond air temperature, especially in drylands. This study investigates the recently compiled Arid Central Asian (ACA) brGDGT surface Data Base, a regional dataset consisting of 753 surface samples from the drylands of ACA. The distribution of brGDGTs in relation to climate and environmental variables was analysed to explore their potential as reliable temperature proxies, mainly focusing on brGDGTs methylation (MBT), cyclisation (CBT), and isomer (IR) indices. The brGDGT-based palaeothermometer is a promising tool for understanding past climates, but our comparison between an ACA-centred database and a worldwide continental surface sample database reveals several challenges. Drylands exhibit extreme climate and soil/lacustrine properties, amplifying the impact of confounding factors on brGDGT-based relationships with mean annual air temperature. Salinity emerges as the dominant factor influencing brGDGT variance, followed by sample type, pH, and aridity, all of which contribute significantly. These factors interact in complex ways, with the salinity effect varying between soil and lacustrine deposits. For sample physicochemical conditions, the IR6+7Me′ index is best for salinity, and IR6Me is most suitable for pH reconstruction. Thus, the MBT5Me′-temperature relationship is limited in ACA, particularly for lacustrine samples, and MBT6Me′ does not offer a better solution under hyper- to semi-arid conditions. Sub-calibrating models for specific environmental conditions such as salinity and aridity improves the accuracy of temperature reconstructions. Furthermore, the difference between MBT5Me′ and MBT6Me′ provides a promising proxy to assess aridity. Although the brGDGT signal in drylands is influenced by multiple controlling factors, it remains a valuable tool for understanding past climate and environmental conditions, especially when accounting for the complex interactions between these factors based on each study's unique physicochemical and bioclimatic context. Further research, incorporating a broader range of surface samples alongside comprehensive soil and climate data, holds the potential to enhance the accuracy of brGDGT-based climate reconstructions
Chlorhexidine vs Povidone-Iodine Alcohol Solutions for Cardiac Implantable Electronic Devices
No full textInternational audienceBACKGROUND Cardiac resynchronization therapy (CRT) improves heart failure outcomes and reduces morbidity and mortality but carries the highest infection risk among cardiac implantable electronic devices. Studies on surgical-site infections show conflicting results regarding the use of alcohol-based povidone-iodine vs chlorhexidine for skin antisepsis, especially as CRT implantation remains insufficiently studied. OBJECTIVES This study sought to compare the effectiveness of 2% alcohol-based chlorhexidine with that of 4-phase povidone-iodine-alcohol skin preparation in preventing local or systemic infections after cardiac resynchronization therapy device implantation, and to assess the impact on other major cardiovascular events and treatment-related adverse effects over 24 months. METHODS In this randomized, multicenter, open-label trial with blinded outcome adjudication, patients undergoing CRT (implantation, upgrade, or replacement) pacemaker, or defibrillator implantation were assigned 1:1 to receive skin antisepsis with either 2% alcoholic chlorhexidine or alcoholic povidone-iodine. Randomization was conducted centrally using an interactive web-response system, with stratification according to trial center. The primary outcome was local or systemic infection related to the device over a 24-month follow-up period. The secondary outcomes were major cardiovascular events and noninfectious side effects. RESULTS From April 2013 to December 2018, 2,272 patients were randomized to the chlorhexidine (n = 1,143) or the povidone-iodine group (n = 1,129). Median age was 72 years; 75.1% were men. Device-related infections occurred in 2.9% of the chlorhexidine group and 3.9% of the povidone-iodine group (adjusted subhazard ratio: 0.75; 95% CI: 0.48-1.20; P = 0.23). Major cardiovascular events occurred in 31.5% and 31.3% of patients, respectively (subhazard ratio: 1.01; 95% CI: 0.87-1.17). Noninfectious local side effects occurred in 12.9% vs 13.3%. CONCLUSIONS The study did not demonstrate a significant reduction in infection rates with alcoholic chlorhexidine compared with alcoholic povidone-iodine in patients undergoing cardiac resynchronization device implantation. Both antiseptics showed similar rates of major infectious and noninfectious events. Further research is needed to optimize infection prevention strategies in this population. (Comparison of Alcoholic Chlorhexidine 2% Versus Alcoholic Povidone Iodine for Infections Prevention With Cardiac Resynchronization Therapy Device Implantation [CHLOVIS]; NCT01841242) (JACC. 2026;87:200-211) (c) 2026 by the American College of Cardiology Foundation
Introduction à la lecture du Traité de l'Harmonie de Jean-Philippe Rameau
No full textInternational audienceOuvrage d'accompagnement à la lecture du Traité : éléments de lexique, résumé du Supplément (corrections) avec des ajouts, résumé commenté du contenu, éléments de lecture thématique
THE EARLIEST RECORD FOR HONEYGUIDES (AVES: INDICATORIDAE), FROM THE EARLY PLIOCENE OF SOUTH AFRICA
No full textInternational audienceTwo new species of honeyguides (Indicatoridae) are described from the Lower Pliocene Upper Varswater Formation at Langebaanweg, South Africa. One of these species is referred to the genus Indicator, as Indicator sp. (taxon A), and comparable in size to the Lesser Honeyguide (I. minor). It is represented by a partial coracoid as well as 12 humeri, eight carpometacarpi, and two tarsometatarsi. The second species is slightly smaller than the Least Honeyguide (I. exilis). It is known from a fragmentary proximal humerus, a carpometacarpus and two tarsometatarsi, and cannot be referred to a particular genus of modern Indicatoridae, hence it is referred to Indicatoridae indet. (taxon B). Both species form the as yet earliest record of honeyguides in Africa and the world, and confirm the presence of woodland with mature trees suitable for cavity-nesting species at Langebaanweg during the Early Pliocene
Charles Brosselard et le Tuḥfat al-i‘tibār : sur la paternité des inscriptions arabes de Tlemcen
No full textInternational audienceCharles Brosselard published in the period beteween December 1859 and May 1862 series of epigraphic inscriptions in the African Revue with the title : Arab’s Inscriptions of Tlemcen. However, our recent edition of the Arab manuscript entitled : Tuḥfat al-i‘tibār fīmā wuğida min āṯār bi-madīnat al-ğidār composed by Sī Ḥammū Ban Rūstān, secretary then mufti of the Arab Bureau in Tlemcen in the 1850s, who questioned the attribution of this first work on the commemorative and funeral inscriptions of Tlemcen. This work accomplished at the request of Charles Brosselard, which was based on his publications and reattributed to Sī Ḥammū Ban Rustān and aqually studied the context of its composition and context as well.Charles Brosselard publia entre décembre 1858 et mai 1862 une série d’édition des inscriptions épigraphiques dans la Revue africaine sous le titre : les inscriptions arabes de Tlemcen. Cependant, notre récente édition d’un manuscrit arabe intitulé Tuḥfat al-i‘tibār fīmā wuğida min āṯār bi-madīnat al-ğidār composé par Sī Ḥammū Ban Rūstān, secrétaire puis mufti du Bureau arabe de Tlemcen dans les années 1850, remet en cause l’attribution de ce premier travail sur les inscriptions commémoratives et funéraires de Tlemcen. Ce travail, accompli à la demande de Charles Brosselard dont il fut la base de ses publications, est à réattribuer à Sī Ḥammū Ban Rustān. Sont également étudiés le contexte de composition ainsi que son contenu
L’anglais comme ressource interactionnelle dans les échanges en intercompréhension romane : entre facilitateur et perturbateur
No full textInternational audienceL’intercompréhension désigne une stratégie de communication plurilingue dans laquelle chaque locuteur s’exprime dans sa langue maternelle, ou dans une langue qu’il maîtrise, appartenant à la même famille linguistique que celle de ses interlocuteurs (Bonvino & Garbarino, 2022). Le principe repose sur la proximité typologique et lexicale des langues (notamment les langues romanes) qui permet à chacun de comprendre l’autre sans qu’il soit nécessaire de recourir à une langue tierce, telle qu’une lingua franca externe. Cette approche favorise la reconnaissance réciproque des répertoires plurilingues et pluriculturels (Coste et al., 1997), et s’inscrit dans une logique d’ouverture, d’inclusion et de valorisation du plurilinguisme.Dans les contextes multilingues internationaux, l’intercompréhension connaît undéveloppement croissant, notamment dans les projets de coopération éducative et de mobilité universitaire financés par l’Union européenne. Elle trouve un terrain fertile au sein des alliances universitaires européennes, comme l’Alliance UNITA – Universitas Montium – qui regroupe onze universités de langues romanes et qui fait de l’intercompréhension un axe central de sa politique linguistique (Corino et al., 2025). En particulier, des initiatives pédagogiques telles que le projet UCIL-IC (UNITA Collaborative International Learning in Intercomprehension) ont permis d’expérimenter concrètement cette pratique en contexte d’enseignement supérieur, dans le cadre d’interactions plurilingues semiguidées entre étudiants, enseignants et personnels administratifs de diverses nationalités (Garbarino & Lesparre, 2022, 2024; Mantegna, 2023). Cependant, cette dynamique intercompréhensive ne se déroule pas dans un videsociolinguistique : elle se heurte à la présence structurelle et symbolique de l’anglais,langue qui continue d’occuper une place prépondérante dans les échanges internationaux. Cela soulève plusieurs interrogations : l’anglais est-il mobilisé comme une ressource ponctuelle permettant de surmonter des incompréhensions momentanées, ou bien devient-il une béquille systématique qui freine l’engagement dans l’intercompréhension ? Dans quelle mesure son usage perturbe-t-il, complète-t-il ou redéfinit-il la logique même de l’interaction plurilingue ? L’anglais agit-il comme un outil de médiation neutre ou comme un vecteur de standardisation linguistique susceptible d’éclipser les langues des participants ? qualitative du corpus UnICO (Corino, Goria & Papa, 2025), constitué d’interactions enregistrées entre locuteurs de langues romanes (français, italien, espagnol, portugais, roumain) lors des séances du projet UCIL-IC. Ce corpus met en lumière la manière dont les locuteurs mobilisent – ou résistent à mobiliser – l’anglais dans les échanges. L’analyse discursive permet d’identifier différentes fonctions interactionnelles assignées à l’anglais : clarificationlexicale ou grammaticale, médiation entre locuteurs, recentrage thématique,signalement d’une rupture de compréhension, ou encore stratégie de sauvetage en casde blocage communicatif, et ainsi de suite (Bonvino & Garbarino, 2022; Cervini & Zucchini, 2025; Corino & Mantegna, 2022; Garbarino & Leone, 2022; Melo-Pfeifer, 2012;2018).Parallèlement, l’étude examine les positionnements des participants vis-à-vis del’usage de l’anglais (Hemming et al., 2011; Robert, 2008), qu’il soit perçu commefacilitateur ou au contraire comme intrusif. Elle explore aussi les e$ets sur la dynamiqueinteractionnelle : rupture ou continuité du fil conversationnel, reconfiguration des alliances linguistiques, évolution des représentations du plurilinguisme, et émergence de formes hybrides de communication.En s’inscrivant dans l’axe « interaction et multilinguisme » du congrès, cette étude vise à contribuer à une réflexion plus large sur les pratiques langagières contemporaines dans les espaces plurilingues. Elle met en lumière les tensions entre deux logiques : d’un côté, une logique d’ouverture propre à l’intercompréhension, qui valorise la diversité et la symétrie des échanges ; de l’autre, une logique de standardisation, portée notamment par la prégnance de l’anglais, qui tend à recentrer les interactions sur une langue dominante. Ce travail participe ainsi à une compréhension nuancée des pratiques plurilingues hybrides, à la croisée des dimensions pragmatiques, interactionnelles et sociolinguistiques (Hülsmann et al., 2025)