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Mineral Chemistry of Li-Bearing Minerals at the Giant Tanco Pegmatite, Canada
No full textInternational audienceThe highly fractionated late Archean Tanco pegmatite (Bernic Lake, SE Manitoba, Canada) is a world-class producer of tantalum and cerium but is also a major source of lithium. In order to better understand the major Li hosts and the overall Li budget of the Tanco pegmatite, the lithium-bearing minerals present here were analyzed for major and trace elements by electron microprobe and laser ablation ICP-MS, respectively. The major Li-bearing minerals present in the Tanco pegmatite are eucryptite (approximately 11.0 wt% Li2O), montebrasite (~11.2 wt%), lithiophilite (9.1 wt%), spodumene (~8.8 wt%), petalite (5.45 wt%), lepidolite (4.36 wt%), and tancoite (5.2 wt%); Li is also present in lithiowodginite, tourmaline, muscovite, beryl, pollucite, and apatite (between 0.1 and 1.3 wt% Li2O). Most of the Li present in Tanco is contained in petalite (69.4% of all the Li present here), followed by spodumene (11.4%), montebrasite (11.1%), and eucryptite (4.0%); all remaining Li-bearing minerals contain 4.0% of the Li present in the Tanco pegmatite. Overall, the Tanco pegmatite contains approximately 0.71 wt% Li2O, on par with previous estimates. The major practical implications of these finding are that (1) all Li-bearing minerals have to be considered to properly estimate the Li endowment of any pegmatite; (2) the main Li-bearing mineral is not always spodumene; (3) the exact and detailed Li mineralogy of a pegmatite will directly affect extraction and processing; and (4) a significant proportion of Li in any pegmatite is contained in other minerals than the main one, be it spodumene of petalite
A pictorial identification key for Mediterranean and Middle Eastern Phlebotomus sand flies
No full textInternational audienceGiven the significance of leishmaniasis as a neglected parasitic disease—ranking second in mortality and fourth in morbidity among vector-borne diseases—and the prominence of the Mediterranean and Middle East regions as key areas for leishmaniasis incidence, the study and precise morphological identification of sand flies, the proven vectors of the disease, is crucial. Unfortunately, despite this importance, there are few reliable references or identification keys for the morphological identification of sand flies in the Middle East and Mediterranean regions. Some are outdated and no longer valid or remain local (restricted to a country). To date, no comprehensive study has been conducted on the sand fly fauna and their morphological characterization across these regions. In response to this gap, we present a comprehensive pictorial identification key for male and female Phlebotomus species of Middle East and Mediterranean areas. The key includes 720 selected photos and illustrations demonstrating discriminative morphological features out of 2,000 collected. Furthermore, a collection including descriptive morphological criteria of sand flies, first description of Phlebotomus species, a comprehensive checklist of Phlebotomus species accompanied by their distribution map across Middle Eastern and Mediterranean countries, as well as extensive information on their morphometry, ecology, medical relevance, synonymy, atypical forms and morphology of female Adlerius species are given. Finally, we provide an online pictorial dichotomous key to facilitate field application
Pandore : automatiser les chaînes de traitement de texte pour les chercheurs en sciences humaines
No full textInternational audiencePandore is a toolkit designed for researchers, teachers, and students in the humanities and social sciences, in particular those without advanced technical coding skills. It enables users to efficiently manage their data through intuitive graphical interfaces, allowing them to collect, prepare, convert, and analyze their data, extract relevant insights, and create interpretive visualizations. Building on extensive feedback from the previous beta version, several improvements have been implemented. This communication outlines these updates, including the resolution of identified bugs and enhancements to the graphical interface to improve user experience. We are currently exploring the feasibility of connecting the platform to the Gallica database at the French national library, with a prototype under development to facilitate enriched resource access. Interoperable and modular Python scripts have also been integrated to extend the platform's functionalities. Tutorials have been finalized to guide users in mastering the tools, and the application is being deployed on a GPU-equipped server to optimize performance for computationally intensive tasks. These advancements position Pandore as a versatile and effective tool for researchers across a diverse range of humanities and social science disciplines.Pandore est une boîte à outils conçue pour les chercheurs, les enseignants et les étudiants en sciences humaines et sociales, en particulier ceux qui n'ont pas de compétences techniques avancées en programmation. Elle permet aux utilisateurs de gérer efficacement leurs données grâce à des interfaces graphiques intuitives, leur permettant de collecter, préparer, convertir et analyser leurs données, d'extraire des informations pertinentes et de créer des visualisations interprétatives.En s'appuyant sur les nombreux retours de la version bêta précédente, plusieurs améliorations ont été mises en œuvre. Cette communication décrit ces mises à jour, notamment la résolution de bugs identifiés et les améliorations de l'interface graphique pour améliorer l'expérience utilisateur. Nous étudions actuellement la faisabilité de connecter la plateforme à la base de données Gallica de la Bibliothèque nationale de France, avec un prototype en cours de développement pour faciliter l'accès aux ressources enrichies. Des scripts Python interopérables et modulaires ont également été intégrés pour étendre les fonctionnalités de la plateforme. Des tutoriels ont été finalisés pour guider les utilisateurs dans la maîtrise des outils, et l'application est en cours de déploiement sur un serveur équipé d'un GPU pour optimiser les performances des tâches à forte intensité de calcul.Ces avancées positionnent Pandore comme un outil polyvalent et efficace pour les chercheurs dans un large éventail de disciplines des sciences humaines et sociales
Early detection of Zymoseptoria tritici infection on wheat leaves using hyperspectral imaging data
No full textData collection: The experiment was conducted on two genotypes of durum wheat (Triticum turgidum durum) cultivated under controlled conditions in a growth chamber. Hyperspectral images were collected in planta for twenty-two days to monitor leaf blotch disease caused by the fungal pathogen Zymoseptoria tritici. Images were acquired on the first ligulated leaf in a non-destructive way using two devices: HySpex VNIR-1800 and HySpex SWIR-384 (Norsk Elektro Optikk, Norway).International audienceThis article presents a hyperspectral imaging (HSI) database of healthy leaves and leaves infected with Zymoseptoria tritici fungal pathogen responsible for leaf blotch (Lb) disease. Leaves of two durum wheat genotypes were studied under controlled conditions to track the evolution of Lb disease and capture significant spectral and spatial differences until the onset of symptoms. Hyperspectral image acquisitions were purchased with two cameras in visible-near infrared (VNIR) and short-wave infrared (SWIR) spectral ranges on eighteen dates between one day before inoculation and twenty days after inoculation. For each wavelength range studied, a total of 1175 images provided information on 3326 leaves measured throughout the experiment. These data are valuable since they can be used as a basis to monitor disease's development over time, to build leaf classification models according to their infection status per genotype per day, to develop prediction models related to symptoms' appearance, or to test imaging and spectral analysis methods
Phytoplankton and zooplankton in relation to Water Framework Directive status in some regulated lowland watercourses of the Scheldt and Sambre (France and Belgium)
No full textInternational audienceAnalysis of the composition, abundance and diversity of phytoplankton and zooplankton communities in channelised rivers from the upper Scheldt/Sambre catchment (France/Belgium) is used to assess the extent to which their distribution is related to Water Framework Directive (WFD) water quality criteria. Phytoplankton and zooplankton communities are differently associated with WFD status of the stations: phytoplankton communities differ between good/moderate and good/poor state, while zooplankton communities are different in poor than in moderate and good state stations. Euglenophytes are characteristic of good status, the rotifer Brachionus angularis of moderate status stations, and diatoms and the rotifer Brachionus calyciflorus of poor status. Phytoplankton blooms only occur in the poor status stations of the Scheldt, probably due to it having higher SiO2 concentrations than the other rivers
Prevalence of post-pandemic SARS-CoV-2 in patients with respiratory syndrome in Brazzaville, Republic of the Congo
No full textInternational audienceThe first confirmed case of COVID-19 was detected in the Republic of the Congo in March 2020. Several control measures were implemented during the pandemic period. As a result, the number of reported cases decreased significantly, leading to the gradual lifting of barrier measures and the declaration of the end of the outbreak on 14 October 2022. The present study aimed to determine the post-pandemic prevalence of SARS-CoV-2 in the referral hospitals of Talangaï (HRT) and Makélékélé (HRM) in Brazzaville between October 2022 and April 2023. Nasopharyngeal samples collected from patients with respiratory syndrome were analyzed via qRT‒PCR to detect SARS-CoV-2. An overall prevalence of 5% of SARS-CoV-2 infection was found, with monthly fluctuations in cases during the study period, likely reflecting the endemic nature of the infection. The monthly proportion of SARS-CoV-2 infection cases did not correlate with the number of patients with respiratory syndrome-related symptoms. Although the post-pandemic prevalence of SARS-CoV-2 has remained low, laboratory confirmation of COVID-19, which accounts for both clinical suspicion and detection of SARS-CoV-2, using at least one rapid diagnostic test (RDT) is needed to improve case-by-case management in health centers
The Expanding Universe of Extensions and Tails: Ribosomal Proteins and Histones in RNA and DNA Complex Signaling and Dynamics
No full textInternational audienceThis short review bridges two biological fields: ribosomes and nucleosomes—two nucleoprotein assemblies that, along with many viruses, share proteins featuring long filamentous segments at their N- or C-termini. A central hypothesis is that these extensions and tails perform analogous functions in both systems. The evolution of these structures appears closely tied to the emergence of regulatory networks and signaling pathways, facilitating increasingly complex roles for ribosomes and nucleosome alike. This review begins by summarizing the structures and functions of ribosomes and nucleosomes, followed by a detailed comparison highlighting their similarities and differences, particularly in light of recent findings on the roles of ribosomal proteins in signaling and ribosome dynamics. The analysis seeks to uncover whether these systems operate based on shared principles and mechanisms. The nucleosome–ribosome analogy may offer valuable insights into unresolved questions in both fields. For instance, new structural insights from ribosomes might shed light on potential motifs formed by histone tails. From an evolutionary perspective, this study revisits the origins of signaling and regulation in ancient nucleoprotein assemblies, suggesting that tails and extensions may represent remnants of the earliest network systems governing signaling and dynamic control
Using reflectance spectra and Pl@ntNet to identify herbarium specimens: a case study with <i>Lithocarpus</i>
No full textInternational audienceThe digitisation of plant collections is bringing large quantities of information into accessible electronic databases. However, in recent decades, traditional taxonomic work in collections has declined, meaning that more specimens are only determined to family or genus, particularly when lacking key identification structures. If unaddressed, large-scale digitisation risks widening the gap between well-studied species and those lacking data.Hyperspectral reflectance and computer vision are two emerging approaches for identifying species, but these have yet to be cross-compared for herbarium-based taxonomy. Using Lithocarpus species as a case study, we compared classification accuracy obtained from leaf reflectance spectra with computer vision (implemented via Pl@ntNet), a RGB (red, green, blue) image-based approach known to work well on specimens presenting reproductive structures. In the spectral approach, we assessed how much data are needed to optimise classification accuracy, how many species could be discriminated between, and whether close relatives were more frequently confounded.We found that Lithocarpus herbarium specimens were accurately identified to species from relatively small spectral datasets. Despite not incorporating reproductive structures, this was only 14% less accurate than [email protected] suggest these rapid, nondestructive leaf reflectance measurements, paired with computer vision, could fill identification gaps in collections, particularly for specimens lacking reproductive features.</div
Brisons la hache et enterrons-la ! Autopsie et réflexions autour du dépôt d'une grande lame polie en fibrolite à Kerarmerrien, Plouzané (Finistère)
No full textInternational audienceDuring exploratory excavation of an area of 23 ha at the north-west tip of Brittany, at Kerarmerrien in Plouzané commune, two fragments of a large polished axehead were found in undisturbed ground. In such a large stripped area, it is remarkable that no arrangement or concentration of Neolithic material was found; this shows that the object had been deposited on its own. The only other evidence for the presence of Neolithic people consisted of several hearths with heat-damaged stones in the surrounding area; these are most likely to date to the Early or Middle Neolithic, to judge from the latest radiocarbon dates. The deposition of this axehead was situated close to the sources of the coastal river Ildut, in a large marshy depression where there is no evidence for a permanent presence of people during the Neolithic. The technical analysis of the axehead shows that it was deliberately broken in two before being buried, and the act of breakage involved a particularly strong transverse blow. The two fragments, which conjoin perfectly with one another, were laid down side by side and head-to-tail, showing a clear intention to position them. The axehead, of an exceptional size (almost 23 cm long), must have taken hundreds of hours to manufacture, involving hammering, sawing and polishing. Macroscopically, the raw material is a massive fibrolite, greenish-yellow with brown patches; its interdigitated fibrous structure is typical of that seen at the outcrops at Plouguin. The results of geochemical analyses (by XRF and Raman spectrometry), compared with those of several raw material samples collected through prospecting, confirm that this is a sillimanite with muscovite, identical to that of the Plouguin outcrops, and more specifically to those at Lanrivanan, in the same commune, just 19 km to the north of the axehead findspot as the crow flies. The axehead, obtained through sawing (as is shown by the asymmetry of its cross-section), is in the form of a teardrop, reminiscent of the Durrington type of axehead made from Alpine rock. The Durrington type, like the Heilles type with which the axehead also shares formal similarities, had a fairly long currency, appearing during the Early Neolithic and disappearing during the Middle Neolithic 2. There is evidence for Neolithic activity during this period in bas Léon, with the number of B-VSG finds multiplying, while the Middle Neolithic evidence (in the form of passage tombs, arrangements of standing stones, settlements and fish weirs reveals a certain patterning in the spatial organisation of activities. The Kerarmerrien find spurred us to re-examine the deposits of axeheads that had been made in Brittany, comparing them with deposits of axeheads made from Alpine rocks that have recently been the subject of synthesis and thorough documentation by Projet JADE (directed by Pierre Pétrequin). Our attention was drawn to an old find (1970), of a complete axe with its haft, brought to the surface through shallow dredging in the Trieux estuary (Côtes-d’Armor), next to a bog. This is known only from a brief mention in a publication. While the haft could not be conserved, photographs taken shortly after its discovery allow us to make out its shape and size, and to draw a parallel with axes known in the Pfyn culture (Switzerland) dating to the first third of the 4th millennium; in these, the head was slotted directly into the haft and the upper end of the haft curves backwards slightly. The large axehead that was found in its haft at Trieux had a perfectly sharp blade and was made from a chrome-rich muscovite with sillimanite – the chrome explaining the very green patches visible on the surface – which points towards the outcrops of Plouguin, in north-west Finistère, as the origin. Rather than imagining a simple loss of this tool as someone crossed a small coastal river, it seems to us more likely that we are dealing with a case of deliberate deposition, connected with the water.Several other findspots in Armorica and elsewhere suggest a deliberate choice of location for axehead deposition (the commonest being on high ground, or close to water, or at a rocky outcrop or beside a standing stone), generally at some distance from settlements or tombs. While the location of the findspot was important, it seems that the manner in which the axeheads were deposited similarly played a key role. Here, the observations made in situ at Plouzané, Carentoir and Lannion offer new insights on the complex question of depositional practices. To this we can add instances where axeheads have been associated with objects that do not seem special but which appear to us, with our prehistorians’ eyes, to relate to the everyday. But, finally, what do we know of the biographies of these polished axeheads outside of their place of discovery; of their chaîne opératoire; and, in certain cases, of the outcrops from which their raw material had been extracted?Dans le cadre d’un diagnostic archéologique réalisé à Kerarmerrien, sur la commune de Plouzané (Finistère), a été mise au jour une remarquable lame polie en fibrolite, brisée en deux. Découverts à environ 0,40 m de profondeur sous la surface actuelle, les deux fragments n’ont pas été affectés par les labours modernes et se trouvaient à quelques centimètres l’un de l’autre. Ils se raccordent parfaitement, sans aucun manque, et forment une grande lame polie en forme de goutte d’eau. Une extension du décapage autour de la découverte et la fouille fine de la zone ont permis de confirmer que la pièce est totalement isolée et ne provient pas du comblement d’une quelconque structure. Le tranchant, bien que légèrement émoussé, mais sans trace de réaffûtage, laisse à penser que nous sommes face à un objet peu ou non utilisé. De même, la lame présente un polissage luisant sur toute sa surface hormis l’extrémité du talon qui conserve encore quelques petites plages brutes. Enfin, si la cassure présente un aspect frais, la patine qui affecte les surfaces atteste son ancienneté. Si nous ne pouvions pas exclure a priori la cassure accidentelle de la lame lors de son utilisation, il semble plus pertinent de nous orienter vers une autre interprétation, celle du bris puis du dépôt de l’objet, envisagés comme des gestes intentionnels. L’analyse typo-technologique, la pétrographie et les comparaisons régionales et internationales sont sollicitées pour tenter d’identifier un scénario. Considérant la position topographique singulière du lieu de la découverte, sur une ligne de partage des eaux et très proche des sources de l’Ildut, la lame polie de Kerarmerrien pourrait en effet témoigner d’une pratique rituelle au Néolithique, celle du dépôt d’un objet socialement valorisé fait aux puissances surnaturelles
Source apportionment of PM<sub>10</sub> based on offline chemical speciation data at 24 European sites
No full textInternational audienceThis study applied Positive Matrix Factorization (PMF) to PM10 speciation datasets from 24 urban sites across six European countries (France, Greece, Italy, Portugal, Spain, and Switzerland) to perform a detailed source apportionment (SA) analysis. By using a consistent source apportionment tool for all datasets, the study enhances the comparability of PM10 SA results across urban Europe. The results identified seven major PM10 sources including road traffic, biomass burning, crustal/mineral sources, secondary aerosols, industrial emissions, sea salt, and heavy oil combustion (HOC). Road traffic emerged as the predominant source of PM10 in urban areas, with contributions varying by location, but representing as much as 41% in high-traffic zones. Biomass burning was detected at 23 sites, contributing 8% to 41% on yearly averages, with substantial increase in winter. Crustal sources were present at all sites (3–33%). Industrial sources contributed relatively less PM10 mass, which was identified at 10 sites with contributions ranging from 2% to 14%. Secondary inorganic and organic aerosol, consisting primarily of ammonium nitrates and sulfates, and organic matter, formed a portion of the PM10 mass (5–41%). These secondary factors are primarily influenced by anthropogenic emissions, including the various combustion processes. Sea salt, predominantly found in coastal areas, contributed between 4% and 21%, reflecting the impact of the marine environments on air quality. This source was very often ‘aged’ (mixed with anthropogenic pollutants from different origins). Additionally, HOC, especially emits from shipping activities, and traced by V and Ni, was also a frequent contributing source (2–15% for 9 sites), indicating a need for more stringent emission controls. The chemical comparison is performed which indicates road traffic and secondary aerosols, showed consistent chemical profiles across sites, while industrial, HOC, and crustal sources displayed significant site-specific variability. These findings underscore the need for tailored air quality strategies according to local sources of emissions and the importance of long-term PM speciation monitoring for effective pollution control