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Comparative study of three cellular materials under blast and sustained shock wave
No full textInternational audienceThis study investigates the mechanical response of three cellular materials—polyisocyanurate (PIR), autoclaved aerated concrete (AAC), and Aluminum Lightweight Foam (ALF, Nufoam® 140)—under blast and shock loading conditions. The research aims to provide experimental data for optimizing building protection against explosion hazards. Laboratory-scale tests were conducted using a shock tube to generate blast and sustained shock waves. The materials’ responses were analyzed using high-speed imaging and digital image correlation. Results indicate that PIR exhibits significant deformation under sustained shocks but shows recovery under blast loading. AAC demonstrates erosion-based energy dissipation, with material loss concentrated at the extremities. ALF, serving as a reference, shows excellent mechanical energy dissipation. The study highlights the potential of these materials for applications requiring both thermal insulation and blast resistance, contributing to the development of predictive tools and larger-scale experiment designs
Lead Isotopes in Mainland Southeast Asia: First Results from Thailand and Perspectives for Comparative Study with China
No full textInternational audienc
Même en cas de licenciement pour faute grave ou lourde, l'indemnité spécifique de rupture conventionnelle est due !
No full textInternational audienceSoc. 25 juin 2025, no 24-12.096 (publié au Bulletin
A dataset of pollen production for 168 common flowering plants in the United Kingdom
No full textInternational audienceNectar and pollen are the two main floral resources consumed by bees, hoverflies and some other flower‐visiting insects. However, most existing datasets on floral resources focus on nectar production, and pollen is usually overlooked. We quantified pollen production for 168 common plant species found in the UK. Our dataset consists of pollen volume per flower, calculated from the number of pollen grains and the volume of a pollen grain. Detailed data collection protocols are presented. Practical implication. This pollen dataset provides a means to identify the high pollen producing species for pollinator conservation purposes, and to estimate pollen production at larger spatial scales when combined with field surveys.Le nectar et le pollen sont les deux principales ressources florales consommées par les abeilles, les syrphes et d'autres insectes floricoles. Cependant, la plupart des jeux de données existants sur les ressources florales se concentrent sur la production de nectar, négligeant le pollen. Nous avons quantifié la production de pollen de 168 espèces de plantes communes du Royaume‐Uni. Notre base de données présente le volume de pollen par fleur, calculé à partir du nombre de grains de pollen et du volume d'un grain de pollen. Les protocoles de collecte des données sont détaillés. Implication pratique. Dans une optique de conservation des pollinisateurs, cette base de données permet d'identifier les espèces très productives en pollen, et permet d'estimer la production de pollen à des échelles spatiales plus larges en combinant ces données à des suivis de terrain
Exemples des limites de l'utilisation de l'IA dans la traduction en sciences humaines
No full textNational audienceL'internationalisation constante de la recherche en sciences humaines, si elle participe au partage et à la circulation du savoir, exige des chercheurs et chercheuses de traduire de plus en plus leur texte pour gagner en visibilité. Dans ce contexte de "publish or perish", les inégalités d'accès et de diffusion amènent naturellement les chercheurs et chercheuses à se tourner vers le TAN ou l'IA, plus rapides et abordables. Or, si ces outils peuvent permettre de défricher le terrain, de comprendre globalement des textes écrits en langue étrangère, leur capacité à gérer la traduction de textes scientifiques, notamment en SHS, a ses limites. A l'aide d'exemples concrets, ces dernières seront abordées lors de cette présentation
Using CE to confirm the activity of fluorescent miRFP670-LIMK1 protein produced for MST assays directly in cell lysate
No full textInternational audienceLIMK1 is a promising therapeutic target for multiple pathologies. Its holistic study seems crucial, as none of its inhibitors has passed clinical trials. The need for new fluorescent probes for the study of enzyme/ligand interactions is always increasing with the development of new analytical tools. A method for the assessment of LIMK activity directly in cell lysate is needed to ensure that interaction studies can be performed close to native conditions and by using active enzymes.Here, we introduce a study of LIM Kinase activity and inhibition monitored directly in cell lysate by capillary electrophoresis (CE). The miRFP670-LIMK1 was prepared because it is a fluorescent fusion protein emitting in the red spectrum and is thus suitable for microscale thermophoresis (MST) affinity assays. A PDADMAC-coated capillary was mandatory to avoid adsorption issues. The results directly confirm, for the first time, that miRFP670-LIMK1 is still active in the cell lysate even when the miRFP670 fluorescent tag is attached to its C-terminal. The inhibition of miRFP670-LIMK1 activity in the presence of TH-257 was also confirmed by CE. The dissociation constant, Kd, of the interaction miRFP670-LIMK1/TH-257 was then evaluated by MST, again directly in the cell lysate without any purification step. Submicromolar cellular on-target activity was revealed (Kd = 9 nM), confirming that TH-257 is suitable as a chemical probe for LIMK1.This study presents an innovative application of CE as a direct approach to verify, in a straightforward and simple manner, without purification or radioactivity, if an enzymatic target maintains its functionality after labeling. This work also highlights the complementarity of CE and MST in advancing pharmaceutical development under conditions that closely mimic those in vivo
Impacts of Tween-20, Glycerol, and Trehalose on Hyaluronidase Activity: Insights from Microscale Thermophoresis and Capillary Electrophoresis
No full textInternational audienceAdditives such as surfactants (Tween-20) and cryoprotectants (glycerol and trehalose) are often used in enzymatic assays to improve the quality and long-term stabilization of proteins. However, these additives can affect the enzymatic activity and the enzyme’s affinity for active compounds, such as inhibitors, and must be considered during assay design since a slight shift in enzyme behavior may compromise the reliability of the results. In this study, the effects of Tween-20, glycerol, and trehalose on hyaluronidase (Hyal) were systematically evaluated by assessing their influence both directly—through microscale thermophoresis (MST) signals of the labeled enzyme (Hyal*)—and indirectly, by monitoring the formation of the final product of the degradation of hyaluronic acid, tetrasaccharide (Tet), using capillary electrophoresis (CE/UV). Hyal was labeled for the first time with ATTO-647 NHS ester, a commercial dye compatible with MST. Efficient labeling was achieved in a phosphate-based buffer without loss of catalytic activity. Tween-20 showed no impact on MST signals nor on enzymatic performance when used between 0.005 and 0.05% (v/v). Glycerol also did not interfere with MST measurements; however, it significantly reduced catalytic activity at concentrations above 2% (v/v). Trehalose affected Hyal* fluorescence in a concentration-dependent manner and enhanced catalytic activity even at 0.02% (v/v)
Experimental Insights into Nucleation, Growth, and Migration of Vesicles in CO2-bearing basaltic melts
No full textUnderstanding how vesiculation occurs in basaltic magmas is key to interpreting volcanic degassing and eruption dynamics. In that purpose, we conducted two experimental series to investigate vesicle formation under CO2-rich conditions. The first simulates CO₂ flushing into a shallow magma reservoir (1200°C, 150-250 MPa, with samples quenched at various experimental times. The second series start from CO2-equilibrium and follows decompression at 0.5 and 5 MPa • min⁻¹, simulating contrasting decompression rates. Our results demonstrate that vesicularity is not controlled by CO2 content alone, but is also influenced by decompression rate, melt viscosity, timing of CO2 input, and the dominant transport mechanism of CO2 (by diffusion or via bubble ascent). Under both static and dynamic decompression conditions, CO2 frequently accumulates at the melt-capsule interface, leading to vesicle loss. This effect is particularly pronounced during gas flushing or when water is present, as the melt is unable to retain all the vesicles, and during rapid decompression, where bubble nucleation and growth are kinetically inhibited despite CO2 supersaturation. These patterns closely reflect natural observations in Mid-Ocean Ridge Basalts, with important implications: (i) vesicularity alone underestimates volcanic CO2 budgets, and (ii) how volatile-rich magmas are capable of remaining effusive under certain conditions
Saint Louis, le roi et les coutumes.: Textes, problèmes et contextes
No full textInternational audienc
bench-MIA: Towards automatic multi-lever benchmark construction for MIA evaluation
No full textInternational audienceThe lack of transparency in large language models (LLMs) training data has created concerns regarding unauthorized data use. Membership Inference Attacks (MIA) offer a method for detecting potential copyright violations and privacy breaches by determining whether specific data points were included during training. However, existing MIA methods face reliability and generalization challenges due to biases in validation datasets. Since various LLMs are trained on different, often proprietary datasets, creating a single universal dataset and evaluation framework is not feasible. In this work-in-progress paper, we introduce bench-MIA, an approach that automatically constructs tailored benchmarks for MIA evaluation. Bench-MIA leverages the concept of lever to systematically generate evaluation datasets addressing key sources of bias. By providing appropriate evaluation baselines for each dataset, bench-MIA facilitates more accurate and fair MIA assessments. Preliminary experimental results demonstrate the impact of these levers on MIA evaluation and motivate further validation