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Immunological and clinical markers of post-acute sequelae of COVID-19: Insights from mild and severe cases six months post-infection
No full textSUMMARY Post-acute sequelae of COVID-19 (PASC) is a complex and multifaceted clinical challenge requiring to emphasize its underlying pathophysiological mechanisms. This study assessed hundreds of virological, serological, immunological, and tissue damage biomarkers in two patient cohorts who experienced mild (n=270) or severe (n=188) COVID-19, 6 to 9 months post-initial infection, and in which 40% and 57.4% of patients, respectively, developed PASC. Blood analysis showed that mains differences observed in humoral, viral, and biological biomarkers were associated with the initial COVID-19 severity, rather than being specifically linked to PASC. However, patients with PASC displayed altered CD4 + and CD8 + memory T-cell subsets, with higher cytokine-secreting cells and increased terminally differentiated CD45RA + effector memory T cells (TEMRA). Elevated SARS-CoV-2-specific T cells responsive to nucleocapsid/membrane proteins with a TEMRA phenotype were also observed. A random forest model identified these features and initial symptom duration as top variables discriminating PASC, achieving over 80% classification accuracy. Highlights Nine months post-initial SARS-CoV-2 infection, over 40% of patients developed PASC Regardless of PASC, the initial disease form influenced the main immune differences PASC led to altered memory T-cell subsets with elevated TEMRA phenotype PASC presence is associated with disease form, initial symptom count and duratio
Paléo BB : Cadre chronostratigraphique des occupations paléolithiques duSeuil de Bourgogne et du Bassin Bressan (Rapport d'opération 2024)
No full textIn 2024, research focused on the Côte-d'Or, in accordance with the recommendations of the CTRA. The work began following the initiation meeting on June 3, alongside the allocation of funding.The research team analyzed existing data (archives, collections, archaeological map, publications) in both archaeological and geological aspects, while also seeking out unpublished sources (documents, collections, oral testimonies). Published interpretations, such as those presented in the works of Martineau et al. (2015) and Djindjian (2023), depict a sparsely and discontinuously occupied territory, primarily in the karstic environment of the Burgundy jurassic sill, with limited scientific visibility.However, the initial extraction of the archaeological map revealed a higher density of information than anticipated, although these data were heavily influenced by earlier discoveries, particularly in areas like the Auxois, highlighting a research bias. The classification of raw data according to a reliability and resolution scale (0 to 5) confirmed the presence of several major sites not only in the Burgundy jurassic sill but also in the Bresse Basin.The study of collections revealed a greater number of Upper Paleolithic sites than previously recorded. Furthermore, some archaeological assemblages are absent from the archaeological map, despite its direct influence on preventive archaeology policies, which impacts the integration of new discoveries. Sedimentary records, however, indicate diverse and abundant occupations, challenging the notion of a sparsely populated Paleolithic landscape. Compared to neighboring regions such as Saône-et-Loire and Yonne districts, the low visibility of Paleolithic occupations in Côte-d'Or appears more related to the limitations of past research. Enhancing the detection of new sites through higher-resolution analyses thus becomes a crucial objective for a better understanding of the region's prehistoric occupation.Geomorphological studies conducted in the Bresse Basin suggest the existence of at least two lacustrine levels (at 220–230 m and 210–200 m), tentatively attributed to MIS 8–10 and MIS 6, respectively. The filling and draining episodes of these water bodies appear to be linked to fluctuations of the Alpine glacial front in the Lyon region. The incision of the current hydrographic network began during MIS 5 through regressive erosion. Within this accommodation space, relatively small alluvial terraces developed, including the lower sandy terrace (Fy) formed at the end of MIS 3, followed by late tardiglacial fine deposits (Caille clays).En 2024, les recherches se sont concentrées sur la Côte-d’Or, conformément aux recommandations de la CTRA. Les travaux ont commencé après la réunion d’initiation du 3 juin, en parallèle de l’attribution de la subvention.L’équipe a analysé les données existantes (archives, collections, carte archéologique, publications) sur les volets archéologique et géologique, tout en recherchant des sources inédites (documents, collections, témoignages). Les interprétations publiées, comme celles des ouvrages de Martineau et al. (2015) et Djindjian (2023), décrivent une occupation faible et discontinue, surtout dans le seuil de Bourgogne en milieu karstique, avec une valorisation scientifique limitée.Cependant, l’extraction initiale de la carte archéologique a révélé une densité d’informations plus élevée qu’attendu, bien que ces données soient fortement influencées par d’anciennes découvertes, notamment dans des secteurs comme l’Auxois, révélant un biais de recherche. Le classement des données selon une grille de fiabilité (0 à 5) a confirmé l’existence de plusieurs sites majeurs, non seulement dans le seuil de Bourgogne, mais aussi dans le bassin bressan.L’étude des collections a révélé davantage de sites du Paléolithique supérieur que recensés jusqu’ici. De plus, certaines séries archéologiques n’apparaissent pas dans la carte archéologique, bien qu’elle oriente les décisions en archéologie préventive, ce qui freine l’intégration des nouvelles découvertes. Les enregistrements sédimentaires montrent pourtant des occupations variées, remettant en question l’idée d’un territoire faiblement peuplé. Par comparaison avec la Saône-et-Loire et l’Yonne, la faible visibilité du paysage paléolithique en Côte-d’Or semble davantage liée aux limites des recherches passées. Améliorer la détection de nouveaux sites avec des analyses plus fines devient donc un enjeu clé pour mieux comprendre l’occupation préhistorique de la région.Les études géomorphologiques menées dans le Bassin bressan tendent à confirmer l’existence d’au moins 2 niveaux lacustres (à 220 - 230 m et à 210 - 200 m) attribués pour l’instant aux MIS 8-10 et au MIS 6. Les épisodes de remplissage et de vidange de ces plans d’eau semblent pouvoir être mis en relation avec les fluctuations du front glaciaire alpin dans la région lyonnaise. Le creusement du réseau hydrographique actuel commence à partir du MIS 5 par érosion régressive. Au sein de cet espace d’accomodation des nappes alluviales peu étendues se sont étagées, principalement la basse terrasse sableuse (Fy) mise en place à la fin du MIS 3, puis les dépôts fins tardi-holocènes (argiles de la Caille)
The exploitation of the globe and nature. The blind spot of environmental considerations in Saint-Simonian industrialism
No full textSaint-Simonianism is often associated with the promotion of a productivist industrialism rooted in science and technology-a model that has fueled, to this day, a tension between its emancipatory and reformist aspirations on one hand, and environmental considerations on the other. This article reexamines that assessment in detail by exploring Saint-Simon's naturalist philosophy and its transformation by his disciples. It highlights and explains lesser-known aspects that add complexity to the initial interpretation without fundamentally challenging it.</div
Simple model for the transition from local to centralized production
No full textInternational audienceWe present a simple model of a crucial phenomenon in modern societies: The shift from local to centralized production, leading to economies of scale and mass production transported over long-distance networks. Agents combine two distinct (and limited) resources, time and raw materials, either to produce for self-consumption or to sell on the market. The model shows a rich landscape of diverse production regimes, including mixed regimes where agents optimize utility by combining time spent working for the market, for self-subsistence, or by taking time off
A broken history : contemporary Lebanon (1958-2018) : how the lure for profit destroyed a nation
No full textInternational audienc
GEF14 acts as a specific activator of the plant osmotic signaling pathway by controlling ROP6 nanodomain formation
No full textInternational audienceDuring their growth, plants encounter and respond to a variety of environmental signals. However, the mechanisms underlying the integration and specificity of signals remain poorly understood. Rho of Plant (ROP) signaling plays a central role in various processes, including polar cell growth and responses to different stimuli, and relies on stimuli-dependent membrane nanodomains. The effector composition of ROP6 nanodomains varies depending on the signal and may be involved in downstream signal specificity. In this study, we explore how ROP6 signaling is regulated by Guanine nucleotide Exchange Factor (GEF) during osmotic stress. We find that GEF14 is required for osmotically induced ROS accumulation. This isoform acts specifically in response to osmotic stimulation, since it is dispensable for other stimuli. We demonstrate that GEF14 activates ROP6 and controls its clustering in a signal-specific manner. Furthermore, we find that GEF14 relocates from the cytoplasm to clusters at the plasma membrane after osmotic stimulation. Together, our results suggest that a single GEF isoform can encode for signal specificity controlling ROP6 activation, clustering and downstream cellular responses
Fluid dynamics of planetary differentiation
No full textInternational audienceThe basic structure of the terrestrial planets-an iron-rich metallic core surrounded by a silicate mantle-was established during their accretion, when widespread melting allowed the metal and silicate phases to separate. The transfer of chemical elements and heat between the metal and silicate that occurred during this period is critical for the composition and initial temperature of the core and mantle, and has important implications for the long-term evolution and dynamics of the planets. After having summarised the main observational constraints on core-mantle differentiation, the article follows the sequence of processes that led to the formation of planetary cores, focusing on the contributions of laboratory fluid dynamics experiments to our understanding of these processes, and discussing the relevance and limitations of this approach to this problem. We first focus on the dynamics of planetary impacts, using laboratory experiments to illustrate and quantify the impact and cratering processes and the resulting metal phase dispersion. We then consider the two-phase flow that follows an impact, when a molten impactor core falls by buoyancy in a magma ocean. The model of miscible turbulent thermal, which we argue is a good reference model for the post-impact flow, is presented. We then discuss how additional factors-immiscibility and fragmentation, inertia inherited from the impact, Coriolis force, sedimentation-affect the predictions of this model, and discuss the extent of chemical equilibration. Finally, a last part of the article is devoted to the migration of the metal phase through a solid part of the mantle.La structure des planètes terrestres — un noyau métallique riche en fer entouré d’un manteau silicaté — a été établie pendant leur accrétion, lorsque la fusion généralisée a permis la séparation des phases métalliques et silicatées. Le transfert d’éléments chimiques et de chaleur entre métal et silicates qui s’est produit pendant cette période est déterminant pour la composition et la température initiale du noyau et du manteau, et a des implications importantes pour l’évolution et la dynamique à long terme des planètes. Après avoir résumé les principales contraintes observationnelles sur la différenciation noyau-manteau, l’article suit la séquence des processus qui ont conduit à la formation des noyaux planétaires, en se concentrantsur les contributions de l’approche de dynamique des fluides expérimentale à notre compréhension de ces processus, et en discutant de la pertinence et des limites de cette approche. Nous nous concentrons d’abord sur la dynamique des impacts planétaires, en utilisant des expériences de laboratoire pour illustrer et quantifier les processus d’impact et de cratérisation, et la dispersion de la phase métallique qui en résulte. Nous examinons ensuite l’écoulement diphasique qui suit un impact, lorsque le noyau d’un impacteur chute dans un océan de magma. Nous introduisons le modèle de thermique turbulent, qui constitue selon nous un bon modèle de référence pour l’écoulement post-impact. Nous discutons ensuite des facteurs additionnels — immiscibilité et fragmentation, inertie héritée de l’impact, force de Coriolis, sédimentation — pouvant affecter les prédictions de ce modèle. Enfin, la dernière partie de l’article est consacrée à la migration de la phase métallique à travers une partie solide du manteau
Percevoir la marche en ville avec un oculomètre (eye tracker). Questions de méthode pour une ethnographie incarnée
No full textInternational audienceAusgehend von einer Vorrichtung zur Aufzeichnung des Gehens mit einem Okulometer (eyetracker) in der Stadt, wird in diesem Artikel der Entstehungsprozess einer inkarnierten, ethnographischen Methode beschrieben, die es ermöglicht eine Handlung in ihrem Ablauf anderer zu begreifen und diese zu analysieren. Diese prozessuale, pluralistische und „integrative“ ethnographische Vorgehensweise – da sie die beteiligten Personen zur Analyse ihrer eigenen Handlung einlädt, führt die Studie über die Fortbewegung im urbanen Bereich durch ihre Analyse in der ersten Person durch. Dieser Ansatz zeigt die enge Beziehung zwischen ethnographischer Ermittlungsvorrichtung und Analysevorrichtung. Die sensible und empathische Beziehung zum Untersuchungsmaterial (Video-Aufzeichnungen der Aufnahmen, Verdeutlichungsgespräche und Selbstkonfrontation), wobei das Erlernen der Wahrnehmung des anderen vorherrscht, bietet die Möglichkeit der von einer Exteriorität beobachteten Daten zu ihrer „inkarnierten“ Wahrnehmung überzugehen. Es geht also darum, die Handlung in ihrem Entstehungsprozess so genau wie möglich zu durchdringen und zu verstehen, wozu sie das Individuum verpflichtet.Based on a device for capturing urban walking using an eye tracker, this article describes the process of emergence of an embodied ethnographic method for accessing and analyzing the actions of others in the process of being performed. This processual, plural and “integrative” ethnographic approach - in which participants are invited to analyze their own actions - studies urban travel through first-person analysis. This approach demonstrates the close relationship between the ethnographic survey device and the analytical device. A sensitive and empathetic relationship with the survey material (video recordings of captures, explanation and self-confrontation interviews), where learning to perceive others and their actions takes precedence, offers the opportunity to move from an exteriority to observational data to their "embodied" apprehension. The aim is to get as close as possible to the action in progress, and to understand what it involves and means for the individual.A partir de un dispositivo de captación de la marcha en la ciudad con un oculómetro (eye tracker), este artículo se propone describir el proceso de emergencia de un método etnográfico encarnado que permite acceder y analizar la acción de los demás. Este enfoque etnográfico procesional, plural y «integrativo» - porque invita a las personas participantes al análisis de sus propias acciones, procede al estudio de los desplazamientos urbanos mediante su análisis en primera persona. Esto demuestra la estrecha relación entre el sistema de investigación etnográfica y el sistema de análisis. Una relación sensible y empática con el material de la encuesta (grabaciones de vídeo de las captaciones, entrevistas de explicitación y de autoconfrontación) donde prevalece aprendizaje de la percepción de los demás y de su acción, ofrece la posibilidad de pasar de una exterioridad a los datos observacionales a su aprensión «incorporada». Se trata, así, de adentrarse en la acción que está ocurriendo de la manera más cercana posible y comprender lo que implica para el individuo.À partir d’un dispositif de captation de la marche en ville avec un oculomètre (eye tracker), cet article se propose de décrire le processus d’émergence d’une méthode ethnographique incarnée permettant d’accéder et d’analyser l’action d’autrui en train de se faire. Cette démarche ethnographique processuelle, plurielle et « intégrative » - car conviant les personnes participantes à l’analyse de leurs propres actions, procède à l’étude des déplacements urbains par leur analyse à la première personne. Cette manière de faire montre l’étroite relation entre dispositif d’enquête ethnographique et dispositif d’analyse. Une relation sensible et empathique au matériau de l’enquête (enregistrements vidéo des captations, entretiens d’explicitation et d’autoconfrontation) où prime un apprentissage de la perception d’autrui et de son action, offre l’occasion de passer d’une extériorité aux données observationnelles à leur appréhension « incarnée ». Il s’agit ainsi de pénétrer l’action en train de se faire au plus près et de comprendre ce qu’elle engage de l’individu
Multi-isotopic (Fe-Cu-Zn) constraints on the magmato-hydrothermal history during mantle exhumation at slow-spreading centers
No full textInternational audienceAt slow to ultraslow-spreading ridges, tectonic mantle exhumation and magmatic processes accounts for heterogeneity in the lithosphere and drives deep hydrothermal circulation and fluids venting at the seafloor. However, the spatio-temporal evolution and the interplay between magmatic and hydrothermal processes during mantle exhumation, as well as their consequences for chemical exchange at mid-ocean ridges are poorly constrained.We carried out a Fe, Cu and Zn isotope study of mantle rocks drilled at the Mid-Atlantic Ridge Kane (MARK) area (23'30°N) to decipher the consequences of magmatic versus hydrothermal chemical exchange on lithospheric mantle composition. At MARK, mantle rocks undergo complex melt-rock interaction during melt percolation overprinted by high temperature (HT, >350°C) hydrothermal circulation that leads to the formation of secondary mineral assemblages (e.g., amphibole, chlorite, ilvaite, hydro-andradite, clinopyroxene, talc, serpentine). Serpentinized peridotites cut by hydrothermally overprinted magmatic veins have increased isotopic heterogeneity to both lighter and heavier isotope compositions (δ 56 Fe from -0.44 to 0.07 ± 0.03‰; δ 66 Zn from -0.24 to 0.32 ± 0.04‰), expending the predictive unaltered composition of the primitive mantle (δ 56 Fe = 0.025 ± 0.025‰ and δ 66 Zn = 0.16 ± 0.06‰). Such variability is ascribed to diffusion-related kinetic isotope fractionation during the percolation of Fe-and Zn-rich melt in mantle rocks. Low isotopic values are due to preferential diffusion of lighter isotope in mantle rocks, while high values may involve mixing of serpentinized peridotites with isotopically heavy magmatic veins. The lower Cu content (0.5 to 23.9 ppm) and either lower or higher δ 65 Cu (-0.11 to 0.32 ± 0.04‰) of abyssal peridotites, compared to the primitive mantle (30 ppm Cu, δ 65 Cu = 0.07 ± 0.1‰), can be explained through Cu leaching during hydrothermal alteration of sulfide, and possibly oxide, at high temperature (~450-600°C). Hydrothermal veins in serpentinites formed at decreasing temperature (~300°C) from a metal-and sulfur-rich fluid interacting with serpentinized peridotites. Iron, Cu and Zn isotopes record the inventory of magmatohydrothermal processes during mantle exhumation at (ultra-)slow spreading centers, from HT melt-rock interaction to late low-temperature (LT) fluid-rock interaction.</div