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Sedimentary Architecture Prediction Using Facies Interpretation and Forward Seismic Modeling: Application to a Mediterranean Land–Sea Pliocene Infill (Roussillon Basin, France)
No full textInternational audienceThis study predicts sedimentary architectures and facies distribution within the Pliocene prograding prism of the Roussillon Basin (Gulf of Lion, France), developed along an onshore–offshore continuum. Boreholes and outcrops provide facies-scale observations onshore, while seismic data capture basin-scale structures offshore. Forward seismic modeling bridges spatial and scale gaps between these datasets, yielding characteristic synthetic seismic signatures for the sedimentary facies associations observed onshore, used as analogs for offshore deposits. These signatures are then identified in offshore seismic data, allowing seismic profiles to be populated with sedimentary facies without a well tie. Predicted offshore architectures are consistent with shoreline trajectories and facies successions observed onshore. The Roussillon prism records passive margin reconstruction in the Mediterranean Basin following the Messinian Salinity Crisis, through the following three successive depositional profiles marking the onset of infilling: (1) Gilbert deltas, (2) wave- and storm-reworked fan deltas, and (3) a wave-dominated delta. Offshore, transitions in clinoform type modify sedimentary architectures, influenced by inherited Messinian paleotopography. This autogenic control generates spatial variability in accommodation, driving changes in depositional style. Overall, this multi-scale and integrative approach provides a robust framework for predicting offshore sedimentary architectures and can be applied to other deltaic settings with limited land–sea data continuity
Ethnomedicinal Applications, Phytochemistry, and Pharmacological Properties of <i>Zanthoxylum caribaeum Lam.</i>: A Comprehensive Review
No full textInternational audienceZanthoxylum caribaeum Lam. is a member of the Rutaceae Family that can be naturally found in South and central America (Brazil, Paraguay, Bolivia, Caribbean, etc.). Its traditional medicinal uses are well documented among native communities, such as that of the Guarani, in Paraguay. More than 60 metabolites, including alkaloids, terpenoids, coumarins, and alkylamides, have been identified in its leaves, bark, and fruits. The biological activities and mechanisms of action of several of these compounds, as well as those of crude extracts, have also been investigated by previous studies. As a medicinal and edible plant, Z. caribaeum shows promising applications in the pharmacological industry. For the last 25 years, a significant amount of research has been conducted with Z. caribaeum to better understand its toxicity and complex mechanisms of action, bringing science-based clinical safety to its traditional uses. This review integrates available knowledge chemical and biological data on this species. It emphasizes the diversity of bioactive metabolites, their associated bioactivities, and provides an updated overview of the plant’s advances in ethnopharmacology, phytochemistry, pharmacology, agricultural exploitation, and potential utilization
Cingulata from the Pliocene and Pleistocene of Pomata-Ayte: New insights from the Bolivian Altiplano
No full textInternational audiencePomata-Ayte is a classic fossiliferous locality located in the Bolivian Altiplano (Oruro Department). First reported by Hoffstetter in 1972, it comprises a series of continental deposits assigned to the Pliocene–Pleistocene Umala Formation. Previous data on the Cingulata (armored xenarthrans) from this locality are scarce and limited to brief mentions of indeterminate glyptodonts, armadillos and the pampatheriid Plaina sp. for the Pliocene levels. We report and describe the diversity of cingulates recovered from Pomata-Ayte, including two different assemblages mostly represented by osteoderms and dorsal carapace fragments. The older assemblage belongs to the Early Pliocene (>5.27 Ma), while the younger corresponds to the Pleistocene (no radioisotopic dating available). For the Early Pliocene, records include representatives of Chlamyphoridae (Chorobates villosissimus and Macrochorobates scalabrinii), Pampatheriidae (Plaina intermedia), and Glyptodontidae (Plohophorini indet). These represent the first records of C. villosissimus and M. scalabrinii in Bolivia, extending their known paleogeographic distribution northwards. The Plohophorini is represented by several dorsal carapace osteoderms, which may belong to either Cranithlastus or Stromaphorus, two closely-related genera with similar osteoderm morphologies. This assemblage shows great affinities with those recorded for Lower Pliocene deposits at higher latitudes, particularly Northwestern Argentina, which contrasts with the endemic pattern recorded for other mammalian clades, including Notoungulata and Folivora, over Pliocene times in the Bolivian Altiplano. For the Pleistocene, records include Chlamyphoridae (Chaetophractus vellerosus) and Glyptodontidae (Glyptodon sp. and Doedicurini indet.). Chaetophractus vellerosus still inhabits the Bolivian Altiplano, so this record traces its presence in the area back to the Pleistocene. Regarding the osteoderms of Doedicurini indet., they are smaller, less thick, and they have a different foramina configuration compared to other Pliocene and Pleistocene doedicurines, which may indicate the presence of a new morphotype in the area. However, more complete materials are needed to corroborate this hypothesis
Oxygénation de l’atmosphère: Chapitre 6
No full textNational audienceCe chapitre retrace l’histoire de l’oxygénation de l’atmosphère et des océans en lien avec l’évolution du vivant, en particulier l’apparition de la photosynthèse oxygénique mais également l’émersion et l’altération d’une croûte continentale différenciée enrichie en éléments bio-essentiels comme le phosphore. L’oxygénation de la planète qui s’échelonne sur près de 3 milliards d’années s’est accompagnée de phases d’innovation biologique majeures comme l’apparition des eucaryotes et l’Explosion du Cambrien, et de cataclysmes climatiques globaux (Terre boule de neige)
Unraveling the effect of convergence obliquity on overriding-plate deformation and strain partitioning in subduction zones
No full textThe subduction of an oceanic plate causes deformation of the overriding plate, from the forearc to the back-arc regions. Over years, to address the physical controls on such a deformation, various compilations on active deformation have been made, mixing various types of datasets including fault-slip rates, focal mechanisms and geodetic motions. The growing amount of available data now allows for the construction of consistent compilations in terms of data types. Here, we present a database for the kinematics of subduction zones which includes that of the overriding-plate deformation, consistently based on geodetic data. The database describes the 2-d (trench-normal and trench-parallel) motions of arc blocks for ~90% of active subduction zones, through the magnitude (vd) and the deformation-obliquity angle (Ovd) between the blocks and the upper plate (undeformed interior of the overriding plate). We classify subduction zones into 4 dominant strain classes (compressional, strike-slip, extensional, and neutral), and into up to 8 classes including intermediate regimes. Focusing on the strike-slip strain class, we show that a non-negligeable trench-parallel motion is a widespread feature of active subduction zones. The convergence obliquity exerts, however, a contrasting effect on Ovd, thereby suggesting a limited effect on strain partitioning at oblique subduction zones. On another hand, Ovd shows a positive correlation with slab dip, where low and high values are associated with compression and extensional classes, respectively. Finally, we provide revised estimations of subduction rates, allowing for instance refined estimations of the thermal parameter, which will permit future comparative investigations on subduction dynamics and tectonic
Mobilités et représentations de l'Empire colonial français : le cas des artistes femmes coloniales (1919-1950)
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Regulation of coral assemblages: Spatial and temporal variation in the abundance of recruits, juveniles, and adults
No full textInternational audienceUnderstanding the processes that maintain coral assemblages is of crucial importance given increasing rates of coral mortality on reefs globally. Here, we compared relationships among distribution patterns of recruit, juvenile, and adult corals with distinct life history traits to determine the contribution of early life stages to the structure of adult assemblages at Toliara, southwest Madagascar. Results highlighted a marked spatio-temporal variability in the abundance of all life stages within and between major reef habitats. Indications of stock-recruitment relationships (where the adults drive the abundance of early life stages) were found for Acroporidae, whereas Poritidae and its dominant genus Porites were likely regulated by recruitment-limitation mechanisms (where early life stages drive the abundance of adults), with significant correlations between the abundance of juveniles and those of adults of the subsequent years. We found stronger links between all life stages for Pocilloporidae, indicative of both recruitment-limitation and stock-recruitment relationships. In contrast, no significant correlations were recorded for the category of ‘other’ families, which is likely the result of mixing taxa with different life history traits. In fact, positive correlations between juveniles and adults were found for Galaxea , Cycloseris , and Pavona genera, which made up the ‘other’ category. The discrepancies of regulation processes among coral taxa highlighted here suggest implementing conservation actions that benefit all life stages. Maintaining the biomass of herbivorous fishes and invertebrates to control algal biomass can benefit coral recruitment and decrease mortality of early life stages and adult colonies. Our results also suggest that sites on the outer slope and on patch reefs, which show higher recruitment rates and abundance of adult colonies, could be considered as recruitment hotspots
Formation Théorique Gestion et Ouverture des Données de la Recherche en Sciences du Vivant et de l'Environnement
No full textNational audienceCette formation aborde tous les aspects théoriques de la gestion et de l'ouverture des données de la recherche en se basant sur chacune des étapes du logigramme de déroulement d'un projet de recherche. De nombreux outils et de nombreuses ressources sont fournies. Cette formation se complète par un atelier pratique de mise en application des concepts abordés
Molecular typing of Mycobacterium tuberculosis : a review of current methods, databases, softwares, and analytical tools
No full textInternational audienceStudies on the epidemiology and clinical relevance of Mycobacterium tuberculosis complex (MTBC) have immensely benefited from molecular typing methods, associated software applications, and bioinformatics tools. Over the last two decades, the Pasteur Institute of Guadeloupe has developed a range of bioinformatic resources, including databases and software, to advance understanding of TB epidemiology. Traditional methods, such as IS6110-RFLP, MIRU-VNTR typing, and spoligotyping, have been instrumental but are increasingly supplanted by more precise and high-throughput techniques. These typing methods offer relatively good discrimination and reproducibility, making them popular choices for epidemiological studies. However, the advent of whole-genome sequencing (WGS) has revolutionized Mycobacterium tuberculosis complex (MTBC) typing, providing unparalleled resolution and data analysis depth. WGS enables the identification of single nucleotide polymorphisms and other genetic variations, facilitating robust phylogenetic reconstructions, and detailed outbreak investigations. This review summarizes current molecular typing methods, as well as databases and software tools used for MTBC data analysis. A comprehensive comparison of available tools and databases is provided to guide future research on the epidemiology of TB and pathogen-associated variables (drug resistance or virulence) and public health initiatives
