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Open data : objectif principal atteint pour les data challenges de la Société Française de Pathologie
No full textInternational audienceThe French Society of Pathology organized two data challenges, with the support of the Health Data Hub: TissueNet in 2020, focusing on cervical lesions, and Visiomel in 2023 dedicated to melanoma in partnership with the French Society of Dermatology and the National Professional Council of Pathologists. The datasets were open a few weeks to competitors worldwide during each challenge. However, these data were then closed, awaiting a complete and permanent opening, known as open data. This ultimate step allows free access to the data to promote global research programs in these diseases. The data from the two data challenges have been available as open data on data.gouv.fr since January 2025 for TissueNet (https://www.data.gouv.fr/datasets/tissuenet-detect-lesions-in-uterine-cervix-specimens-open-data-set/) and since September 2025 for Visiomel (https://www.data.gouv.fr/datasets/visiomel-database-predicting-cutaneous-melanoma-relapse/). Making health data open is a demanding multi-step process - organizationally, technically, and regulatorily - and it is this process that we discuss here
From data to reality: Criteria for the validation of data-driven models for history-dependent materials
No full textInternational audienceThis paper addresses the issue of validating identified data-driven material models for history-dependent materials, which are nowadays typically represented using neural networks. For this purpose, we introduce an a posteriori general acceptability criterion based on the Constitutive Relation Error (CRE). A computed solution using the identified material model is deemed acceptable if it closely approximates the experimental data when using the CRE metric
An inter-comparison of inverse models for estimating European CH <sub>4</sub> emissions
No full textInternational audienceAtmospheric inversions are widely used to evaluate and improve inventories of methane (CH4) emissions across scales from global to local, combining observations with atmospheric transport models. This study uses the dense network of in situ stations of the Integrated Carbon Observation System (ICOS) to explore how well in situ data can constrain European CH4 emissions. Following the concept of inter-comparison studies of the atmospheric tracer transport model inter-comparison Project (TransCom), a CH4 inverse inter-comparison modeling study has been performed, focusing on Europe for the period 2006–2018. The aim is to investigate the capability of inverse models to deliver consistent flux estimates at the national scale and evaluate trends in emission inventories, using a detailed dataset of CH4 emissions described and presented here for first time. Study participants were asked to perform inverse modelling computations using a common database of a priori CH4 emissions and in-situ observations as specified in a protocol. The participants submitted their best estimates of CH4 emissions for the 27 European Union (EU-27) member states, the United Kingdom (UK), Switzerland, and Norway. Results were collected from 9 different inverse modelling systems, using 7 different global and regional transport models. The range of outcomes allows us to assess posterior emission uncertainty, accounting for transport model uncertainty and inversion design decisions, including a priori emission and model-data mismatch uncertainty. This paper presents inversion results covering 15 years, that are used to investigate the seasonality and trends of CH4 emissions. The different inversion systems show a range of a posteriori emission adjustments, pointing to factors that should receive further attention in the design of inversions such as optimising background mole fractions. Most inverse models increase the seasonal cycle amplitude, by up to 400 Gg month−1, with the largest adjustments to the a priori emissions in Western and Eastern Europe. This might be due to underestimation of emissions from wetlands during summer or the importance of seasonality in other microbial sources, such as landfills and waste water treatment plants. In Northern Europe, absolute flux adjustments are comparatively small, which could imply that the emission magnitude is relatively well captured by the a priori, though the lower station density could contribute also. Across Europe, the inverse models yield a similar decreasing trend in CH4 emissions compared to the a priori emissions (−12.3 % instead of −9.1 %) from 2006 to 2018. While both the a priori and the a posteriori trend for the EU-27 are statistically significant from zero, their difference is not. On a subregional scale, the differences between a posteriori and a priori trends are more statistically significant over regions with more in-situ measurement sites, such as over Western and Southern Europe. Uncertainties in the a priori anthropogenic emissions, such as in the agriculture sector (cows, manure), or waste sector (microbial CH4 emissions), but also in the a priori natural emissions, e.g. wetlands, might be responsible for the discrepancies between the a priori and a posteriori emission shift in the trends in Western, Eastern and Southern Europe. Our results highlight the importance of improving the inversion setup, such as the treatment of lateral boundary conditions and the model representation of measurement sites, to narrow the uncertainty ranges further. The referenced dataset related to the analysis and figures are available at the ICOS portal: https://doi.org/10.18160/KZ63-2NDJ (Ioannidis et al., 2025)
Gas-phase spectroscopy of chiral molecules
No full textInternational audienceGas-phase spectroscopy of chiral moleculesMolecular recognition is strongly influenced by several factors including chirality and molecular flexibility. Chirality indeed modifies the interactions at plays between molecules and flexibility allows them to mutually adapt their shape for optimising the interaction. We will describe here gas-phase studies that are sensitive to both chirality and conformation.In the first part, we will describe conformer-selective laser spectroscopy studies of weakly bound complexes, which allow assessing the influence of chirality of the sub-units on the structure of the complex, to understand the nature of the forces responsible for chiral recognition at the molecular level.The second part will be devoted to photoelectron circular dichroism (PECD). PECD is defined as a forward-backward asymmetry in the photoelectron angular distribution for randomly oriented chiral molecules photo-ionised by circularly polarised light (CPL). Like all the chiroptical spectroscopy methods, it is very sensitive to small differences in the molecular structure, including conformational isomerism. We recently developed a conformer-selective PECD scheme based on resonance-enhanced multiphoton ionisation (REMPI) that allows obtaining separately the PECD of each conformer of a chiral system
Intent to Treat Analysis of the Primary and Secondary Outcomes for the ODINN Intact Fish Skin Graft for Deep Diabetic Foot Wounds Trial.
No full textInternational audienceThere is a significant need for trials that evaluate the treatment of University of Texas (UT) grade 2 and 3 diabetic foot ulcers (bone, joint, or tendon exposed wounds). We undertook a trial looking at the effect of intact fish skin graft (IFSG) on these deep and difficult-to-heal ulcers. 262 patients Intent to Treat (ITT) patients with UT grade 2 and 3 DFUs were randomised to receive intact fish skin graft (IFSG) or a standardised treatment (SOC) that adhered to the International Working Group on the Diabetic Foot (IWGDF) guidelines. The secondary endpoints that were measured included wound area reduction (WAR), healing rates at 20 and 24 weeks; closure rates by UT grade, perfusion, quality of life, pain reduction and IFSG safety. We report ITT (all randomised) (mITT previosly reported) The (WAR) at 12 weeks was 65.53% for IFSG versus 30.82% for SOC (p = 0.007). UT 2 wounds (60% of total) exhibited a closure rate of 47% versus 23% at 16 weeks for IFSG versus SOC (p = 0.0033). Target wound infections were comparable (39 vs. 37) and major outcomes were comparable during the 24 week period (target-limb amputations 8% vs. 7%). Time-to-heal favoured IFSG (restricted mean to 24 weeks 17.31 vs. 19.37 weeks; KM/log-rank significant; Cox HR 1.59). The in the treatment of deep complex diabetic foot wounds the addition of IFSG significantly improved the number of patients with total wound closure as well as the time to wound closure without increased risk of complications. This improvement in total wound closure and time to wound closure was noted across prior amputation status, quality of perfusion, and UT grade
From biofuels to e-fuels: an assessment of techno-economic and environmental performances
No full textInternational audienceThe energy transition, alongside sufficiency measures, demands massive electrification supported by low-carbon electricity. However, carbon-based molecules will remain vital, especially in sectors like long-distance transport (aviation, shipping) and chemicals. Biogenic, atmospheric, or recycled carbon sources offer key alternatives to fossil fuels in the shift toward a circular carbon economy, aligning with sustainability goals like the Renewable Energy Directive (RED III). Based on 183 case studies, this workanalyzes thermochemical conversion processes for fuel production, using lignocellulosic biomass, CO2, and low-carbon hydrogen from electrolysis. Nine biofuel, e-fuel, and ebiofuel processes are evaluated, producing liquid hydrocarbons, synthetic natural gas, or methanol. Material and energy balances, determined using ProSimPlus®, compare carbon conversion and energy efficiency. Economic analysis estimates investment and production costs for industrial-scale units, while a greenhouse gas (GHG) assessment considers different electricity mixes and biomass supply chains. Results show that substituting biomass with hydrogen improves carbon conversion: from 35-40% for biofuels to 65-70% for e-biofuels, and up to 80-85% for e-fuels with carbon capture. Hybrid energy sources boost energy efficiency for e-biofuels (61.3%) compared to biofuels (50.3%). However, using electricity (100 e/MWh) raises production costs, heavily dependent on electricity price assumptions. Aligning e-fuel and e-biofuel production with RED III requires a largely decarbonized electricity mix, while more comprehensive emissions assessments are necessary for biofuels and e-biofuels, considering potential land-use impacts of massive biomass production
Theoretical study of the RbHe electronic excited states
No full textInternational audienceWe investigate the electronic excited states of the RbHe molecule with the help of ab initio model core polarization potential (AIM-CPP). We focus on the lowest-energy states correlating with the Rb atom excited states, up to the 4f configuration. To assess the quality of our approach, we compare the potential energy curves (PECs) with the most accurate ab initio wave function methods, MRCI and CCSD(T). We also compare the transition energies from 5p to 5d configurations with the high-resolution experimental absorption spectrum obtained by interferometric method. Our analysis shows that the AIM-CPP method is remarkably reliable and accurate to predict the PECs and related ro-vibrational states of the RbHe molecule
Comment la Chine développe « l’économie de basse altitude »
No full texthttps://theconversation.com/comment-la-chine-developpe-leconomie-de-basse-altitude-27621
Helium superluminous SN 2021bnw : an explosion of a massive star with a pre-outburst
No full textInternational audienceSuperluminous supernovae (SLSNe) remain an intriguing topic in supernova (SN) transient astronomy. While the majority of SLSNe are shown to be explained by energy streaming from the newly born magnetar, there are others which are powered by different mechanisms. We analyse the pseudo-bolometric light curve of the nearby helium-rich SLSN 2021bnw. We built models and run hydrodynamics radiative-transfer simulations with STELLA. Our best-fit models include 15-22.5 Msun of ejecta enriched with 1.7 Msun of 56 Ni and carrying energy of 4 foe, and colliding w ith 7 Msun of circumstellar matter which match the observed light curve very well. The early data can be explained as cooling of an expanding shell with the mass of 0.5 Msun and kinetic energy of 0.7 foe. We tend to exclude a pulsational pair-instability (PPISN) origin for SLSN 2021bnw. Instead we conclude that SLSN 2021bnw was preferably a core-collapse explosion of a star with the initial mass of not less than 61 Msun aided by magnetorotational effects
Critique écosystémique des droits humains
No full textInternational audienceL'urgence écologique exige la mise en place de contraintes sur le système productif, et donc sur les modes de consommation qui en découlent. Mais celles-ci sont bien souvent repoussées comme autant d'atteintes aux libertés fondamentales. Semble ainsi s'opérer une confusion entre liberté individuelle et mode de vie non soutenable, qui façonne les représentations individuelles, sociétales, médiatiques, politiques, jusqu'à rejaillir dans la sphère juridique où se manifestent les tensions entre protection de l'environnement et préservation des libertés fondamentales. Cet amalgame court-circuite la réflexion sur les changements sociétaux à conduire pour faire face à l'urgence écologique via le spectre de l'« écologie punitive » ou de la « dictature verte ». Le projet de recherche CritÉcoDhu -Critique écosystémique des droits humains : repenser les « droits de l'Homme » à l'aune des limites planétaires -vise à repenser la fondamentalité des droits dans le cadre d'un nouveau contrat social lié à l'urgence écologique. Ce premier ouvrage collectif, issu d'un séminaire de cadrage entre juristes, philosophes, politistes, anthropologues et climatopaléontologue, réunit tout à la fois des études de cas, des analyses inédites et des relectures critiques de textes fondamentaux qui confrontent libertés individuelles, urgence environnementale et démocratie