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VOC emissions from in-use asphalt pavements: Environmental drivers, atmospheric impacts, and mitigation strategies
No full textInternational audienceVolatile organic compounds (VOCs) emitted from asphalt pavements are increasingly recognized as contributors to urban air pollution and associated health risks. While emissions during production and paving have been widely studied, continuous releases during the service life of pavements remain poorly quantified, despite asphalt covering over 90 % of global road surfaces and up to 20 % of urban areas. These in-use emissions are influenced by binder type, mixture design, and environmental drivers such as temperature, solar radiation, humidity, and material aging. Recent chamber studies show that hydrocarbons and oxygenated VOCs dominate at service temperatures (20–70 °C), contributing to ozone and secondary organic aerosol (SOA) formation with yields of 10–20 % of the reacted VOC mass. Mitigation strategies such as warm mix asphalt, recycling, and bio-based binders reduce production-phase emissions, yet their effectiveness in limiting service-phase releases remains uncertain. This review consolidates current knowledge on VOC emissions from in-use asphalt pavements and highlights major gaps, including the absence of standardized quantification methods and emission factors suitable for inventories within life-cycle assessment frameworks. Addressing these gaps is essential in order to comprehensively evaluate the current contribution of asphalt pavements to urban air quality and to guide sustainable infrastructure strategies that mitigate the effects of climate change
Community challenge towards consensus on characterization of biological tissue: C4Bio’s first findings
No full textInternational audienceThis study investigates methodological variability across various expert laboratories worldwide, with regards to characterizing the mechanical properties of biological tissues. Two testing rounds were conducted on the specific use case of uniaxial tensile testing of porcine aorta. In the first round, 24 labs were invited to apply their established methods to assess inter-laboratory variability. This revealed significant methodological diversity and associated variability in the stress–stretch results, underscoring the necessity for a standardized approach. In the second round, a consensus protocol was collaboratively developed and adopted by 19 labs in an attempt to minimize variability. This involved standardized sample preparation and uniformity in testing protocol, including the use of a common cutting and thickness measurement tool. Despite protocol harmonization, significant variability persisted across labs, which could not be solely attributed to inherent biological differences in tissue samples. These results illustrate the challenges in unifying testing methods across different research settings, underlining the necessity for further refinement of testing practices. Enhancing consistency in biomechanical experiments is pivotal when comparing results across studies, as well as when using the resulting material properties for in silico simulations in medical research
Friction on Demand: A Generative Framework for the Inverse Design of Metainterfaces
No full textInternational audienceDesigning frictional interfaces to exhibit prescribed macroscopic behavior is a challenging inverse problem, made difficult by the non-uniqueness of solutions and the computational cost of contact simulations. Traditional approaches rely on heuristic search over low-dimensional parameterizations, which limits their applicability to more complex or nonlinear friction laws. We introduce a generative modeling framework using Variational Autoencoders (VAEs) to infer surface topographies from target friction laws. Trained on a synthetic dataset composed of 200 million samples constructed from a parameterized contact mechanics model, the proposed method enables efficient, simulation-free generation of candidate topographies. We examine the potential and limitations of generative modeling for this inverse design task, focusing on balancing accuracy, throughput, and diversity in the generated solutions. Our results highlight trade-offs and outline practical considerations when balancing these objectives. This approach paves the way for near-real-time control of frictional behavior through tailored surface topographies
Les promoteurs immobiliers privés à l’épreuve de la sobriété et de la circularité dans la métropole nantaise
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Sociologie du luxe
No full textInternational audienceL’attrait pour les biens et les services de luxe comme pour les métiers de la filière n’a d’égal que le dynamisme économique de ce secteur mondialisé.Loin des pamphlets convenus, de l’essayisme mondain et des fresques historiques basées sur des panégyriques d’entrepreneurs, Vincent Chabault propose un panorama des connaissances sociologiques produites sur le luxe. Il expose les enjeux de ce secteur, de la création à la consommation en passant par la diffusion et la vente.Une synthèse indispensable à l’heure où le luxe investit un nombre croissant de domaines – gastronomie, art, édition, prêt-à-porter –, étend son influence auprès d’une clientèle toujours plus large et prétend incarner, par le caractère intemporel de ses créations, une réponse face à la crise climatique, qui lui confère ainsi une nouvelle légitimité
Independent set reconfiguration: general and RNA-focused parameterized algorithms
No full textInternational audienceThe computation of energy barriers between RNA structures is a classic NP-hard problem in Bioinformatics, of which the Independent Set (IS) reconfiguration in bipartite graphs represents a natural generalization. Parameterized algorithms, based on parameters taking limited or bounded values on biological instances, are thus crucial towards practical solutions. In this work, we show that bipartite IS reconfiguration is slice-wise Polynomial (XP) solvable for both the {range} of IS sizes allowed along the reconfiguration, and the {arboricity} when the input is restricted to a circle graph. Such a setting is relevant to Bioinformatics as it provides a solution to the RNA energy barrier problem.We propose algorithms based on a {divide-and-conquer} approach, yielding a -space, -time algorithm for the range , and a -space, -time algorithm for the arboricity .Then, we demonstrate the practicality of these algorithms on a benchmark consisting of random RNA instances
Additive manufacturing for improving supply chain resilience under the ripple effect
No full textInternational audienceAdditive manufacturing (AM) is a revolutionary technology gaining substantial interest from academia and industry. Facing supply chain (SC) disruption risks, AM helps SC partners restore capacities through in-house and on-demand production. Compared to common resilience strategies, e.g. using backup suppliers and outsourcing, AM can reduce structural SC redundancy and enhance responsiveness to market demands. However, AM's impacts on SCs under the ripple effect remain insufficiently explored. This work investigates a SC resilience improvement problem by combining a novel AM strategy with inventory redundancy. For the problem, a dynamic Bayesian network is applied to portray the ripple effect, and a problem-specific Markov decision process is proposed to quantify the impacts of resilience strategies. A new mixed-integer non-linear non-convex optimisation model is established to minimise the disruption risk, and a Q-learning-based genetic algorithm is designed for solving large-scale problems. Key managerial insights from the case study include: (i) the proposed approach assists SC managers in prioritising key partners and implementing differentiated strategies based on partners' positions within the SC under limited budgets; and (ii) the temporal factor is critical, necessitating AM machine rentals for immediate post-disruption response and early AM machine purchases to ensure long-term resilience
Autrices de théâtre du XVIe au XVIIIe siècle : disponibilité en ligne et visibilité
No full textNational audienceLe croisement de bases de données en ligne, issues de bibliothèques, de travaux de recherche, de structures associatives ou d’initiatives personnelles, permet à la fois de recenser les pièces de théâtre écrites par des femmes du XVI au XVIII siècle, d’en récupérer des versions numériques et de collecter des informations relatives à la visibilité de leurs autrices. Nous présenterons la méthodologie qui a été suivie pour créer le site web Théâtre de femmes 16-18 et la base de données associée, dans le cadre du projet de recherche Cité des dames, créatrices dans la cité. En s’appuyant notamment sur de précédents travaux comme ceux de David Trott, du projet de recherche Play Summary 18 de Carol Sherman, Perry Gethner, Althea Arguelles-Ling ou encore du Répertoire du théâtre français imprimé au XVIIe siècle d’Alain Riffaud, le site web recense plus de 400 pièces, dont plus de 250 avec une version numérisée en mode image et plus de 70 avec accès au texte intégral.En présentant les divers sites web qui fournissent des numérisations de pièces, nous verrons de quelle manière la disponibilité en ligne de ces pièces progresse, avec parfois l’utilisation de plateformes numériques collaboratives pour l’établis se ment du texte. Ces constats incitent, dans l’objectif d’une meilleure accessibilité des oeuvres, à adopter les bonnes pratiques de la science ouverte pour établir et mettre à disposition les données et les textes. Nous montrerons en particulier comment l’utilisation comme base pivot de la base de données collaborative Wiki data permet d’enrichir les informations mises à disposition sur le site, à propos des pièces et de leurs autrice
Acting together for a positive future: A cross-cultural investigation of how environmental cognitive alternatives and efficacy beliefs contribute to individual and collective biodiversity-conservation intentions
No full textInternational audienceMotivating citizens to individually and collectively engage in favor of biodiversity conservation is a fundamental challenge of current society. But what are the drivers that motivate individuals to engage in biodiversity conservation actions? Growing interest in recent research on behavioral change for climate change mitigation is brought to individuals' perception of the future, and more precisely how individuals' ability to envision a positive eco-friendly future can be a fundamental step for behavioral change with regards to climate change mitigation. We argue that two important socio-cognitive dimensions need to be integrated in the modelling of biodiversity conservation intentions, related to individuals' appraisal of collective coping: the perceived ability to imagine a positive future and efficacy beliefs with regards to behavioral and social changes in favor of biodiversity conservation. To this purpose, we carried out an exploratory correlational study, collecting data from France and Germany, China and the USA (total N = 2000). Present findings confirm that the ability to imagine a positive future and efficacy beliefs, together with social identity, social norms and attitudes, are strong correlates of biodiversity-conservation intentions, both at an individual and collective level. These findings offer important insights on envisioning positive futures as a significant factor supporting proenvironmental intentions
BEDS: Bayesian Emergent Dissipative Structures: A Formal Framework for Sustainable Digital Twins and Continual Learning Systems
No full textThis document presents a theoretical framework called **BEDS** (Bayesian Emergent Dissipative Structures). The central observation: what we call "learning" in machine learning, "dissipation" in thermodynamics, "evolution" in biology, and "proof" in mathematics exhibit similar structural patterns. We propose a unified formalism to describe these patterns.The document is structured in five parts:1. **Analogy** — Building intuition through the river metaphor2. **Conjecture** — Connecting Gödel, Landauer, and Prigogine3. **Formal Results** — Mathematical constants as fixed points of inference4. **Implementation** — A sustainable P2P network architecture5. **Discussion** — Implications and open questions**Disclaimer.** The formalism presented here is deliberately simple — perhaps too simple, and I may have reinvented existing results. This is speculative work born from stepping back and reflecting on my research. It does not include a systematic literature review and does not reflect the rigor of my peer-reviewed academic work. Most of it was developed with Claude Opus 4.5 (claude.ai). However, I find this angle of attack compelling enough to share — hopefully others will find something valuable in it too.Ce document présente un cadre théorique appelé BEDS (Bayesian Emergent Dissipative Structures). L’observation centrale est la suivante : ce que nous appelons « apprentissage » en apprentissage automatique, « dissipation » en thermodynamique, « évolution » en biologie et « démonstration » en mathématiques présentent des structures formelles similaires. Nous proposons un formalisme unifié pour décrire ces motifs communs.Le document est structuré en cinq parties :Analogie — Construction de l’intuition à l’aide de la métaphore de la rivièreConjecture — Mise en relation de Gödel, Landauer et PrigogineRésultats formels — Les constantes mathématiques comme points fixes de l’inférenceImplémentation — Une architecture réseau pair-à-pair durableDiscussion — Implications et questions ouvertesAvertissement. Le formalisme présenté ici est volontairement simple — peut-être trop simple — et il est possible que j’aie redécouvert des résultats déjà existants. Il s’agit d’un travail spéculatif, né d’une prise de recul et d’une réflexion sur mes propres recherches. Il ne comporte pas de revue systématique de la littérature et ne reflète pas la rigueur de mes travaux académiques évalués par les pairs. La majeure partie de ce travail a été développée avec Claude Opus 4.5 (claude.ai). Néanmoins, je trouve cet angle d’attaque suffisamment intéressant pour le partager — en espérant que d’autres y trouveront également matière à réflexion