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Les sites de la Peyzie (Lisle, Dordogne). Une histoire en construction
No full textInternational audienceThe Dordogne department and, in particular theVézère valley, played a key role in the developmentof prehistoric archaeology and the recognition of theauthenticity of its artistic productions. Many of thesites in the area have been the focus of sustainedand regular research for over 150 years, polarisingscientific and economic interests. But other parts ofthe department, rich in prehistoric sites, appear tohave been neglected. Located in the north-west ofthe Dordogne department, the mid-Dronne valleyis one of these little-known areas, even though anumber of sites excavated during the 20th centuryreveal recurrent settlement during the Upper andLate Palaeolithic periods.Located in the present-day commune of Lisle, La Peyzie is a steepslope with several small south-facing caves opening onto a small,flat valley, which may have functioned seasonally as a fluvio-polje.The site is a limestone ledge on the right bank of the Donzelle river,300 m long and around ten meters high. It is a little-known site, bothto the non-specialist public and to prehistorians themselves. Rarelymentioned in scientific literature, the site is best known for havingyielded a number of singular objects that have now disappeared.This lack of knowledge of the site is due as much to a gap in thedocumentation surrounding the first excavations carried out inPeyzie I under the direction of Paul-Émile Jude in the 1930s, as to thedispersal of the artefacts unearthed. Nearly 90 years later, throughthe compilation of unpublished archives and a return to the field,we propose to redefine the geomorphological and historiographicalframework of the Peyzie sites in order to see what contributions(and limitations) they have made to the construction of regionalprehistoric archaeology.The archives relating to the early excavations at Peyzie I include anumber of previously unpublished documents, such as manuscriptsand letters from the main protagonists at the time, various illus-trations, as well as some of the archaeological material recovered.They enable us to reconstruct some of the events that took placeon the site nearly a century ago, and to link them to the historyof local prehistoric archaeology, which was still in its infancy atthe time. First of all, they reveal that emblematic names in Frenchprehistory, such as Henri Begouën and Denis Peyrony, visited the siteand encouraged its excavation. But despite the support and adviceof his contemporaries, Jude left behind very little usable data fromhis excavations at Peyzie I. The difficult excavation conditions in thecave (in particular the rising water table) probably partly explainthis finding, at a time when the search for beautiful objects (rare atPeyzie I) was still a widespread practice.In addition, the compilation and revision of this data mean that,if not confirming the archaeo-sequence established by Jude(centered on the Upper Magdalenian and Azilian periods), we canat least complete it by recognising both earlier (during the earlymiddle Magdalenian) and more recent passages (during the earlyLaborian). It is also surprising to note that Peyzie I is better knowntoday for its contribution to the characterisation of the (beginningof the) MM – which P.-É. Jude did not recognise on excavation – thanto that of the upper Magdalenian or Azilian. Finally, these archivesconfirm the paucity of usable data left by these early excavations.This deprives us today of a sequence that could have contributedto characterising the evolution of human societies during thePleistocene/Holocene transition in the north-east of the AquitaineBasin, and in particular to the debates surrounding the azilianisationprocess. It is on the strength of this desire to find and reconstruct thePeyzie I archaeosequence that we have begun a research program inthe Donzelle valley in 2019.The aim of this return to the field was (1) to find the site excavated inthe 1930s by P.-É. Jude and check whether any archaeological levelswere still present and usable, (2) to test the archaeological potentialof the rest of the calcareous escarpment, and (3) to characterisethe geomorphological formation of the valley and its sedimentaryevolution. The two excavation campaigns we carried out at Peyzie Icall into question the archaeological potential of the site. Althoughthe bone industry describes a possible Magdalenian level at thebase of the fill, several elements argue in favour of sorted andmixed assemblages. Firstly, the absence of clearly individualisedarchaeo-stratigraphic units in the pit, the inconsistent stratigraphicposition of the only dated faunal remain and the lack of "beautifulobjects". This is also the case with the intrusion of elements fromthe modern period throughout the sequence (i.e. glass, plastic,wood, iron elements, etc.), as well as from the Ice Age in the first(supposedly Azilian) strippings. Lastly, this is supported by thearchival documents to which we have had access, which describethe Jude excavations as having extended over the entire cave andreaching the rocky floor in places. In short, there is every reasonto believe that the survey we began in 2019 intersects a series ofbackfills from the Jude excavations and flood deposits that wouldhave redeposited in the cavity. Given the difficult excavation condi-tions (cramped conditions and rising water table), these elementsno longer reassure us of the value of excavating this site, whichdoes not present the conditions of archaeological integrity requiredas part of our research project. But if these initial results appearnegative, they will at least have had the merit of drawing attentionto this limestone ledge, whose archaeological potential is far fromexhausted.Indeed, the discovery of Peyzie IV in 2019, a small cave about70 metres northeast of Peyzie I, opens up new avenues of researchin this sector. The excavations we have carried out over 12.5 m2 onthe entrance porch have revealed not only surface levels disturbedby various taphonomic processes, but also a homogeneous deeperlevel attributed to a period of the recent Palaeolithic that is stilllittle known in the region (the late Middle Magdalenian). Continuedresearch in this area will enable us to check the homogeneity andextent of this level and to study its various components. Ultimately,this will enable us to reconstruct environmental variations in thenortheastern Aquitaine Basin during the Heinrich stadial 1, a par-ticularly cold and dry episode during the last deglaciation whoseeffects on landscapes, animal and human communities have yetto be described. So, in addition to the sites of Rochereil and Pontd'Ambon, which represent the upper Magdalenian/Azilian/Laboriansequence (Célérier 1998; Paillet, Paillet 2022), this sector now offers,over an area of less than a square kilometer, unrivalled potentialfor documenting the adaptations and evolutions of human groupsin Northern Aquitaine during the early Dryas (terrestrial equivalentof the Heinrich 1 event).Bien qu’aujourd’hui largement méconnue, la cor-niche rocheuse de la Peyzie s’inscrit pourtant dansl’histoire de l’archéologie préhistorique locale.Localisée dans la moyenne vallée de la Dronne(Dordogne), à proximité de sites de renom commePont d’Ambon ou le Fourneau du Diable, elle a livréplusieurs grottes dont l’une (Peyzie I) fut fouilléedès les années 1930 par Paul-Émile Jude alors enquête d’une première expérience de fouille. Menéesdans des conditions difficiles (liées aux remontées de la nappephréatique), ces fouilles n’ont laissé que peu de données exploi-tables, parmi lesquelles figurent plusieurs objets remarquables,d’origine douteuse ou aujourd’hui disparus. À travers la compilationd’archives inédites, assortie d’un retour sur le terrain à des fins géo-morphologique et archéologique, cette contribution fait le point surles apports et les limites des grottes de la Peyzie à la constructionde l’archéologie préhistorique régionale. Si cette reprise d’étudeinvalide le potentiel archéologique de Peyzie I (dont l’archéo-séquence est plus étendue que ce que P.-É. Jude avait initialementperçu), la campagne de sondages à laquelle nous avons procédéle long de la corniche a permis de mettre au jour un nouveau sitemagdalénien, Peyzie IV, dont l’étude (en cours) s’avère prometteusepour éclairer l’évolution des sociétés humaines au cours du Dryasancien (équivalent terrestre de l’évènement d’Heinrich 1)
Actualités 2025 en neurosciences fondamentales : présentée par Armelle Rancillac (Chargée de Recherche à l’Inserm, Collège deFrance, Paris).
No full textIn this presentation at the Strasbourg Sleep Congress, Armelle Rancillac, a researcher at Inserm and the Collège de France in Paris, presented a summary of the most significant work published in 2025 on sleep in fundamental neuroscience. The selected studies were presented around four themes: (i) the molecular and cellular mechanisms of sleep pressure, (ii) the genetic variability of sleep needs, (iii) brain cleansing, and finally (iv) the effects of contextual determinants such as stress and external temperature.Dans cette présentation au Congrès du Sommeil de Strasbourg, Armelle Rancillac, chargée de recherche à l’Inserm, au Collège de France à Paris, a exposé une synthèse des travaux marquants publiés en 2025 sur le sommeil en neurosciences fondamentales. Les études sélectionnées ont été présentées autour de quatre axes : (i) les mécanismes moléculaires et cellulaires de la pression de sommeil, (ii) la variabilité génétique des besoins de sommeil, (iii) le nettoyage du cerveau, et enfin (iv) les effets des déterminants contextuels tels que le stress et la température externe
Low latency global carbon budget indicates reduced land carbon sink in the year 2024
No full textInternational audienceIn 2024, the atmospheric CO2 growth rate based on the globally averaged marine boundary layer (MBL) observations from the National Oceanic and Atmospheric Administration (NOAA) network reached 3.73 ± 0.08 ppm yr−1, marking a record high since continuous measurements began in 1959 (Fig. 1a) [1]. The whole-atmosphere growth rate derived from independent OCO-2 satellite observations for 2024 was 3.20 ± 0.1 ppm yr−1 using the Growth Rates from Satellite Observations data-driven approach (GRESO) from Ref. [2], the highest value of the OCO-2 record since 2015. The whole-atmosphere growth rate derived from our flux inversion models assimilating OCO-2 observations mainly over land for 2024 was 3.23 ± 0.12 ppm yr−1, thus unsurprisingly being almost equal to GRESO and less than the MBL stations but still a record high in the OCO-2 inversions record since 2015. This 38.15% increase in the CO2 growth rate between 2023 and 2024 occurred despite fossil fuel CO2 emissions increasing by only 0.85% [3]. This highlights an unprecedented weakening of the net carbon uptake on land and ocean. Net land uptake is defined here as the sum of non-fossil land CO2 fluxes including photosynthesis, respirations, fire, rivers and land-use change emissions. Here, we present a low latency global and regional carbon budget for 2024, using top-down inversions and bottom-up models, revealing a strong weakening of the global net land carbon sink and widespread transitions of terrestrial regions from carbon sinks to sources
Real-life use of bone-targeting agents for bone metastases in France between 2009 and 2018: Results of the OPTIMOS study
No full textInternational audienceAim: To determine the use of bone-targeting agents (BTAs) in clinical practice in France and the occurrence of skeletal-related events (SREs) in cancer patients with bone metastases.Methods: This study analysed data, recorded prospectively in a French National Health Insurance database, for patients who had a first diagnosis of bone metastases between 2009 and 2018.Results: A total of 6,663 patients were analysed (mean age 69.7 ± 13.2 years, 53.2 % male) corresponding to 2,363 bone metastases only patients and 4,300 patients with SREs at inclusion. The most frequent primary cancers were breast (15.8 %), prostate (13.4 %), lung (12.6 %) and digestive cancer (10.6 %). Six-hundred and twenty-one patients (9.3 %) were treated with BTAs (52.7 % with denosumab). Median [IQR] time between inclusion and BTA initiation was similar with denosumab (3.3 months [1.2-7.9]) and bisphosphonates (3.3 months [1.2-8.7]). Patients with a SRE at inclusion and early BTA initiation (≤3 months) had a significative lower incidence of a second SRE at 12 months than those with late initiation (13.6 % [95 %CI: 8.1-20.4] vs. 21.6 % [14.8-29.2] respectively; p < 0.001).Conclusion: BTAs are underused in bone metastases patients in France. There is an urgent need to optimise bone metastases management in accordance with ESMO 2020 guidelines
Highly conductive ester-based solid electrolyte exhibiting remarkable stability for safe, sustainable, and high-performance lithium metal batteries
No full textInternational audienceSince the 1970s, polymer electrolytes (PEs) such as poly(ethylene oxide) (PEO) have been extensively studied to address the instability and safety issues associated with lithium metal electrodes. However, these conventional PEs suffer from low lithium transference numbers and narrow electrochemical stability windows. In this work, we introduce innovative solid-state PEs based on crosslinked poly(butyl malonate) (CPBM) and lithium salts. Unlike traditional PEO-based PEs, CPBM-based PEs are fully amorphous and self-standing, offering a suite of superior electrochemical properties. Notably, they exhibit comparable ionic conductivities to PEO-based PEs but achieve significantly higher lithium transference numbers and an impressive limiting current density enabling efficient ion transport. Another remarkable feature of our CPBM-based PEs is their wide electrochemical stability window, extending up to 4.7 V vs. Li/Li+, and an excellent stability with lithium metal. These substantial improvements in electrochemical stability have been rigorously validated through long-term cycling stability tests, including Li stripping/plating and full cells with LiFePO4 (LFP) and Mn-rich LiMn0.6Fe0.4PO4 (LMFP) electrodes. We firmly believe that polymalonate-based PEs represent a pioneering solution to overcome the limitations inherent in PEO-based PEs and pave a way to safe, high-performance lithium metal batteries, marking a significant leap forward in battery technology
Linear Reservoir: A Diagonalization-Based Optimization
No full textWe introduce a diagonalization-based optimization for Linear Echo State Networks (ESNs) that reduces the per-step computational complexity of reservoir state updates from O(N^2) to O(N). By reformulating reservoir dynamics in the eigenbasis of the recurrent matrix, the recurrent update becomes a set of independent element-wise operations, eliminating the matrix multiplication. We further propose three methods to use our optimization depending on the situation: (i) Eigenbasis Weight Transformation (EWT), which preserves the dynamics of standard and trained Linear ESNs, (ii) End-to-End Eigenbasis Training (EET), which directly optimizes readout weights in the transformed space and (iii) Direct Parameter Generation (DPG), that bypasses matrix diagonalization by directly sampling eigenvalues and eigenvectors, achieving comparable performance than standard Linear ESNs. Across all experiments, both our methods preserve predictive accuracy while offering significant computational speedups, making them a replacement of standard Linear ESNs computations and training, and suggesting a shift of paradigm in linear ESN towards the direct selection of eigenvalues
Pliocene contrasted climate conditions in space and over time: A unique pollen dataset from the NW Mediterranean Region for comparison with climate models
No full textInternational audienceA set of 62 Pliocene pollen records and reconstructed climate parameters across the Northwestern Mediterranean Region, together with palaeoclimate simulations from the IPSL earth system model, provide a unique opportunity to study the Pliocene, especially the early Piacenzian Cooling (ePC) and the mid-Piacenzian Warm Period (mPWP). Vegetation reconstructed from pollen records documents strong spatial contrasts in the area. It reveals a retreat of the subtropical broad-leaved evergreen forest to the advantage of Mediterranean sclerophyllous ecosystems.This study is a first attempt to compare observation-based data with model simulations in the Northwestern Mediterranean Region. It reveals substantial discrepancies with encouraging results, pointing out the need to expand the work of data -model comparisons to other regions. The mid-Piacenzian warm period appears to be an interesting past analogue for the ongoing anthropogenic global warming, including its regional impacts. We observe that two areas (Northern Catalonia and the Southern Alps-Liguria) were affected by increased precipitation during brief episodes in the mid-Piacenzian, while the Roussillon-Languedoc-Provence area experienced drier conditions. Such a spatial pattern seems comparable with the present-day context. The significance of ecosystems composed of some Cupressaceae (Cupressus-Juniperus-type) is interpreted partially as subtropical forest, and partially as Mediterranean vegetation. This regional study provides valuable data and interpretations to improve the contribution of past records to such evaluations, and inspires future palaeoclimate simulations with finer resolution
Molecular characterisation of the invasive terrestrial nemertean Geonemertes pelaensis: long and complex mitogenome and presence of NUMTs
No full textInternational audienceThe complete mitochondrial genome of the invasive terrestrial nemertean Geonemertes pelaensis Semper, 1863 (Nemertea: Prosorhochmidae) was sequenced from two specimens collected in geographically distant French overseas territories—Martinique in the Caribbean and New Caledonia in the South-West Pacific. In both specimens, the mitogenome contained 13 protein-coding genes, two rRNA genes, and 21 tRNA genes, and was unusually large, approaching 32 kb. The two genomes differed by only four single nucleotide polymorphisms and one indel. A comparison with 22 cox1 sequences available in GenBank confirmed this high level of genetic conservation, suggesting a recent introduction from related source populations. The extraordinary length of the mitogenome was largely attributable to two extended regions comprising only tRNA genes and long intergenic sequences. These results were contrasted with data from an unpublished SRA sequencing project (SRS20559370) of an unlocalized specimen identified as G. pelaensis; its reconstructed mitogenome was only 18 kb in length (14 kb shorter) and showed extensive sequence divergence. Phylogenetic analyses placed this specimen as the sister lineage to G. pelaensis, highlighting the need for further investigation of this taxon. In the Martinique specimen, several NUMTs (nuclear mitochondrial pseudogenes) were also detected, which could complicate future studies relying solely on Sanger sequencing. Sequencing additionally revealed prey DNA from the gut contents of both worms: the New Caledonian specimen had consumed an unidentified noctuid moth, while the Martinique specimen had likely fed on the invasive cockroach Periplaneta australasiae (Fabricius, 1775), itself an introduced species
Spectral sirens cosmology from binary black holes populations with sharper mass features
No full textInternational audienceSpectral-sirens inference enables the extraction of cosmological parameters from gravitational-wave data alone, without electromagnetic counterparts or galaxy catalogs. We introduce new parametric mass functions for the binary black hole population that capture significant structure across the mass spectrum and are moderately favoured by Bayesian evidence over simpler models. Analysing the latest gravitational-wave transient catalog, GWTC-4.0, we show that powerlaws-only population models constrain the Hubble constant to precision, at confidence level. This represents a improvement over the corresponding binary black hole-only analysis by the LIGO-Virgo-KAGRA collaboration, achieving precision comparable to their joint analyses including neutron stars and galaxy catalogs. We further test alternative cosmological models, establishing competitive constraints on modified gravitational-wave propagation, while bounds on the dark energy equation-of-state parameters remain uninformative. Projecting to future O5 observing run, we forecast substantial improvements in and modified propagation parameters with larger datasets at higher redshifts. Our results highlight the strong interplay between the black hole mass distribution and inferred cosmology, underscoring the need for suitable population models to fully exploit gravitational-wave data