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No evidence of bowhunting in Magdalenian antler points: Comment on Langley and Lombard (2025)
No full textInternational audienceIn the study of prehistoric projectile points, the tip cross-sectional area method (TCSA) is often used to hypothesize about projectile delivery mode. In a recent article, Langley and Lombard applied this method, combined with point mass, to Magdalenian antler points from southwest France. Their results suggest the likelihood of bowhunting at some sites, and one point subtype, the Lussac-Angles point, is particularly highlighted as possible arrow tip because of its low TCSA and mass. However, the methods used in this study underestimate TCSA and mass, particularly when composite weapon tips are considered. Experimental evidence shows that Lussac-Angles points can be used with the spearthrower, and there is also archeological and experimental evidence of use with the spearthrower for fork-based points, another type of Magdalenian antler point that has a TCSA similar to the Lussac-Angles points. These findings refute the evidence of bowhunting in Magdalenian antler points and offer another example of the problems raised by the use of the TCSA method to reconstruct past weapon systems
Graph Neural Networks for Graph-Level Regression on Heterogeneous Network Data: Use Case in Early-Stage Optimization of Software Mapping on Multicore Platforms
No full textInternational audienceAccurately predicting the power consumption and latencyof software applications deployed on multicore platforms is a criticalbottleneck for early-stage performance optimization, as it often relies onslow and costly simulations.To address this challenge, we introduce a graph-based methodology thatmodels the mappings of software applications onto multicore architecturesas heterogeneous graphs. We then investigate Graph Neural Networks(GNNs) to predict power consumption and latency for these mappings.Four classes of state-of-the-art GNNs were trained under variousconditions on 11 datasets, each containing multiple mappings of agiven Neural-Network application. The two best-performing GNN classesachieve mean absolute percentage errors of around 2% for power-consumptionprediction and 15% for latency. Inference requires only a few tens ofmilliseconds per prediction. This work demonstrates that GNNs offer afast and promising approach to performance prediction, opening the doorto AI-assisted optimization of software mapping on multicore platforms.The relevance of our work extends beyond the use case: we introduce anoperational framework for GNNs to support heterogeneous graph processingand multi-output regression at the graph level
Transcriptomic plasticity in hybrid schistosomes can contribute to their zoonotic potential
No full textInternational audienceHybrids between Schistosoma haematobium and Schistosoma bovis contribute to human and animal infections, highlighting complex interspecies interactions that facilitate schistosomiasis transmission. Schistosoma bovis infects multiple ruminant hosts, promoting cross-species transmission and increasing zoonotic risk. This study explores transcriptomic plasticity as a mechanism enabling hybrid schistosomes to adapt to different definitive hosts. We analysed two contexts: (1) introgressed S. haematobium × S. bovis hybrids, which exhibited higher virulence in sheep than parental S. bovis; and (2) S. bovis infecting different mammalian hosts. Introgression, the transfer of genetic material between species through hybridization and repeated backcrossing, was associated with 366 differentially expressed genes (4% of coding genes) between introgressed hybrids and S. bovis in sheep. Additionally, S. bovis showed host-dependent transcriptomic changes, with 30% of genes differentially expressed between infections in hamsters and sheep. Enriched biological processes shared across introgression and host adaptation included nuclear mRNA catabolism and inner mitochondrial membrane organization, indicating increased gene expression plasticity and metabolic adaptation to environmental stress. These findings suggest that transcriptomic plasticity enhances the adaptability of S. bovis and hybrid worms, increasing their zoonotic potential. This raises concerns for schistosomiasis control, as such plasticity could expand transmission capacity and complicate intervention strategies.This article is part of the Royal Society Science+ meeting issue ‘Parasite evolution and impact in action: exploring the importance and control of hybrid schistosomes in Africa and beyond’
Impact of oxic and thermal transient phases on corrosion of carbon steel in different cementitious media: insights from new in situ experiments
No full textInternational audienceThe impact of oxic and thermal transient phases on corrosion of carbon steel in a cementitious environment was studied through three in situ experiments (Tournemire underground research laboratory, France). For 2 years, heated metallic samples (80°C) were placed in direct or indirect contact with two different cementitious materials: a low-pH bentonitic cement grout (BCG) and a Portland cement paste material (CEM I). Mineralogical and microstructural analyses were carried out in an attempt to identify the combined effects of pH, chemistry and microstructure properties associated with such specific cementitious media on steel corrosion mechanisms. Additionally, in situ electrical resistance corrosion sensors allowed continuous monitoring of the corrosion rates corresponding to each of the three field experiments. Post-mortem characterization indicated that metallic samples embedded in low-pH BCG were heavily damaged and exhibited high corrosion rates. Conversely, steel samples in contact with a highly alkaline CEM I environment appeared to be much less impacted by corrosion processes and revealed extremely low corrosion rate values. A comparison between these field experiments observations and results previously obtained through complementary laboratory mock-up tests finally enabled the evaluation of the impact that variations in geometrical/design aspect existing between in situ and laboratory tests can induce on material degradation
An intense peak of paraglacial dismantlement of mountain slopes: Insights from dating and volume quantification of rock-slope failure deposits in the Icelandic Westfjords (Dýrafjörður and Önundarfjörður)
No full textInternational audienceParaglacial rock slope failures (RSFs) are prominent processes of landscape evolution in deglaciated terrains, such as the Westfjords of Iceland. This study aims to provide chronological and volumetric data on RSF deposits in the Dýrafjörður and Önundarfjörður fjords, in order to document the magnitude, duration, and geomorphic impact of the intense peak of Early and Middle Holocene paraglacial denudation. By refining the timing of a paraglacial signal, this work contributes to a better understanding of sedimentary production and landscape evolution during the Holocene.A total of 17 RSFs was studied, described and mapped using the Schmidt-hammer exposure-age dating method, calibrated with radiocarbon dating. Surficial block morphometry and volumetric estimates of RSF deposits were derived from field measurements, orthophotography, and high-resolution digital elevation models.RSF ages are concentrated in the Early to Middle Holocene. The vast majority of this activity occurred between 12 and 6 cal. ka BP. During this 6000-year interval, ~83 million m3 of debris were deposited, which accounts for approximately 90% of the total volume (~92.5 M m3) from all 17 RSF sites. This indicates a primary paraglacial adjustment phase characterized by high sediment delivery efficiency. Slope reactivations occurred over periods up to 3400 years, with superimpositions of deposits: these are multi-phased RSFs.Finally, a significant lag of approximately 3000 years is observed between the deglaciation (~10.2 cal. ka BP) and the peak in rock-slope failure activity (8–6 cal. ka BP), which coincides with the Holocene Thermal Maximum climax in Iceland (8.6–5.2 cal. ka BP). The subsequent cessation of major RSFs activity after ~4 cal. ka BP marks the transition to a stable, non-glacial equilibrium
Une aide automatisée à la décision partagée ? Réflexion juridique sur un système automatisé d’aide à la décision médicale pour la sclérose en plaques
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Shortcomings of Linear-Response TD-DFT for ESA Oscillator Strength Calculations
No full textInternational audienceWe present an evaluation of linear-response (LR) TD-DFT for the calculation of excited-state absorption (ESA) oscillator strengths. Specifically, we compare this approach with the computationally more expensive quadratic-response (QR) scheme, which we previously benchmarked, J. Chem. Theory Comput. 21 (2025) 4688, and analyze the deviations between the two approaches using various metrics. Three subsets of molecules and ESA transitions are considered: (i) subset A, a data set of 21 compact molecules comprising 53 ESA transitions, (ii) subset B consisting of 9 large molecules inspired by real-life fluorescent dyes, and (iii) subset C of selected molecules in their relaxed S1 geometries. For subset A, we identify a clear relationship between the single-reference character of the excited states involved in the ESA process and the magnitude of the QR-LR deviations. Additionally, we observe a significant correlation between the contribution of the TD-DFT de-excitation vectors, the single-reference character of one of the two excited states, and the QR-LR discrepancies. For both subsets B and C, the correlations observed in subset A are less pronounced. Nevertheless, the largest outliers consistently involve at least one state with strong de-excitation components. Finally, we propose a simple linear correction for the unrelaxed LR oscillator strengths. Overall, LR-TD-DFT tends to almost systematically overestimate ESA oscillator strengths, especially when one of the two excited states involved exhibits large de-excitation contributions
Formation dynamics of an ethylene carbonate-derived solid–electrolyte-interphase in commercial Li-ion batteries
No full textInternational audienceThe importance of the solid–electrolyte-interphase (SEI) is well-established in lithium-ion (Li-ion) batteries, but the technical story behind its formation remains incomplete. Current research has largely focused on the nature of the deposited layer, while the formation dynamics, particularly those occurring in the solution phase, remain elusive. Here, by employing operando infrared fiber evanescent wave spectroscopy (IR-FEWS) to conduct real-time monitoring of the chemical dynamics of ethylene carbonate-based electrolytes and graphite anodes, we reveal that the assembly of the SEI layer follows a classical heterogeneous nucleation and growth process under appropriate kinetic constraints. Our findings, supported by various other in situ/ex situ techniques, show that during charging, the newly generated species (e.g. lithium ethylene dicarbonate (LEDC) and Li2CO3), that are destined for the SEI, can also diffuse away from the graphite–electrolyte interface into the electrolyte. The deposition of the species occurs via a heterogeneous nucleation process with the low-solubility inorganic species (e.g. Li2CO3) preferentially nucleating on the graphite surface, followed by more-soluble organic species (e.g. LEDC). Limiting diffusion to promote the deposition is crucial for facilitating efficient SEI formation with competitive deposition kinetics depending not only on the charging rate and temperature, but also the electrolyte quantity. When the formation parameter-space is intentionally modified by employing a high current pulse during initial charging followed immediately by an ageing step, a more stable SEI with lower resistance is developed, leading to longer lifetimes for the Li-ion pouch cells prepared with this new protocol. Collectively, these findings deepen our mechanistic understanding of SEI formation from the “solution” phase perspective and offer an enriched framework for defining initial charging protocols for battery manufacturing
Assessment of the tritium analysis performance of a nonylphenol-ethoxylate-free liquid scintillator by interlaboratory comparison
No full textInternational audienceWith a view to using liquid scintillators compliant with the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals) regulations, some laboratories have expressed an interest in testing the ProSafe LT+ , a liquid scintillator without nonylphenol-ethoxylates (NPE). In order to evaluate the impact of using this new liquid on the analysis results, the CETAMA consortium organised two interlaboratory comparisons. Two ranges of tritium activity were selected to meet the needs of environmental and waste monitoring. 23 laboratories took part in these exercises, comparing results obtained with Prosafe LT+ to those obtained with NPE-containing liquid scinitllators. From the results it was seen that the background and the background noise obtained with the nonylphenol-ethoxylates-free liquid scintillator are not significantly different from that of the usual liquid scintillator, whether for the waste or environmental domain, over short (15 min) or long (200 min) counting times. Furthermore, the decision threshold and the detection limit values estimated with ProSafe LT+ were no different from those of usual scintillators. However, for the measurement of samples, and particularly for samples with a tritium activity above 15 Bq/kg, the ProSafe LT+ presented a reduced measurement quality compared to the nonylphenol-ethoxylates-containing LS i.e. the measurement uncertainty obtained with ProSafe LT+ is systematically higher. In light of the results obtained through this study, the authors recommend the use of the ProSafe LT+ with the proviso that the deterioration in measurement uncertainty be taken into account and found to be compatible with a laboratory’s individual needs
Classical notions of computation and the Hasegawa-Thielecke theorem
No full textExtended version with more illustrations and proofsInternational audienceIn the spirit of the Curry-Howard correspondence between proofs and programs, we define and study a syntax and semantics for classical logic equipped with a computationally involutive negation, using a polarised effect calculus, the linear classical L-calculus. A main challenge in designing a denotational semantics for the calculus is to accommodate both call-by-value and call-by-name evaluation strategies, which leads to a failure of associativity of composition. In order to tackle this issue, we define a notion of adjunction between graph morphisms on non-associative categories, which we use to formulate polarized and non-associative notions of symmetric monoidal closed duploid and of dialogue duploid. We show that they provide a direct style counterpart to adjunction models: linear effect adjunctions for the (linear) call-by-push-value calculus and dialogue chiralities for linear continuations, respectively. In particular, we show that the syntax of the linear classical L-calculus can be interpreted in any dialogue duploid, and that it defines in fact a syntactic dialogue duploid. As an application, we establish, by semantic as well as syntactic means, the Hasegawa-Thielecke theorem, which states that the notions of central map and of thunkable map coincide in any dialogue duploid (in particular, for any double negation monad on a symmetric monoidal category)