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Comparison between ex-situ and in-situ soot particle size and number density distributions in swirl stratified turbulent premixed ethylene/air flames
No full textInternational audienceTwo measurement diagnostics were developed to study soot production in swirl stratified premixed ethylene/air flames. The first one measures the spatially-resolved mobility diameter and number density distributions of soot using a dual-port dilution sampling probe connected with a second dilution system and a Scanning Mobility Particle Sizer (SMPS). The second technique relies on high-speed 2D multi-angle light scattering diagnostic (2D-MALS) enabling the measurement of 2D spatially-resolved distributions of soot gyration diameter and number density. The gyration diameter is derived from the data processing of scattering images collected by CMOS cameras located at 45◦ and 135◦ around the flame while the data recorded at 90◦ with another CMOS camera combined to the knowledge of the gyration diameter, enables the determination of the soot number density.Performances of both diagnostics were compared by measuring in various operating conditions of swirl stratified premixed ethylene/air flames, the mean mobility diameter and particles’ number density by SMPS, then by recording the single-shot 2D distributions of gyration diameter and particles’ number density, under given assumptions on the diameter of primary spheres, at a repetition rate of 800 Hz by 2D-MALS. Because the SMPS system reports mobility diameters and 2D-MALS provides gyration diameters, a conversion procedure of mobility diameter into gyration diameter was developed to compare effectively the mean soot size and number density distributions recorded by both diagnostics. The good agreement between the results indicates that the dual-port dilution sampling probe coupled to the SMPS provides accurate measurements of mean particle size and number density distributions in turbulent flames, with the exception of high-gradient regions adjacent to the flame frontand ambient air, where disturbances in flame properties and soot oxidation can be observed. Furthermore, 2D-MALS offers the additional advantage of recording the temporal and 2D spatial evolution of soot properties (size and number density) in turbulent flames
Long-term exposure to particulate air pollution and components in relation to breast cancer risk: A nested case-control study in the E3N-Generations cohort
No full textInternational audienceBackground: Previous studies on the association between airborne particulate matter(PM), particularly PM₂.₅ and PM₁₀, and breast cancer have shown inconsistent results,potentially due to variations in particle composition. To address this, we investigatedthe relationship between breast cancer and exposure to individual PM2.5 and PM10components, as well as their combined effects, in the French E3N-Generation.Methods: We conducted a nested case-control study within the cohort (1990–2011),including 5,222 incident breast cancer cases matched to 5,222 controls. Annual meanconcentrations (μg/m³) of pollutants at residential addresses were estimated usingthe CHIMERE chemistry-transport model from 1990 to the index date. Exposureassessment included nine PM components: ammonium, sulfates, black carbon,polychlorobiphenyl-153 (PCB153), nitrates, benzo[a]pyrene, cadmium, dioxins, andSaharan dust. We evaluated single-pollutant effects using simple and logisticregression, and mixture effects using Quantile G-computation (QGC) and BayesianKernel Machine Regression (BKMR).Results: Significant positive associations with breast cancer (Odds Ratios andconfidence intervals for one SD increase (controls distribution) were found forammonium (OR=1.19; 95%CI:1.05–1.35, sulfate (OR=1.17; 95%CI:1.02–1.34), PCB153(OR=1.16; 95%CI:1.08–1.26), nitrate (OR=1.15; 95%CI:1.01–1.32,black carbon(OR=1.12; 95%CI:1.05–1.19), cadmium (OR=1.05; 95%CI:1.00–1.11). QGC showed apositive association with breast cancer for a one-quartile increase in joint exposure(OR=1.22; 95% CI:1.00–1.50) with cadmium and nitrate as major contributors. BKMRconfirmed a significant positive association between the mixture and breast cancer.Conclusion: The consistency between single-pollutant and mixture analyses supportsa role for multiple PM components acting jointly on breast cancer risk. These resultssuggest that the chemical composition of PM, rather than individual pollutants alone,is a key determinant of breast cancer risk, highlighting the importance of consideringpollutant composition in air pollution research
A Multi-LLM Agent System for Modular Ontology Population: A Case Study on ADHD
No full textInternational audienceModular ontologies play a crucial role in structuring and interpreting complex knowledge, where they enable the representation of contextual information from diverse sources. To fully exploit these ontological models, a population phase is essential, involving the enrichment of the ontology with concrete instances. However, the automatic population of such ontologies from heterogeneous sources remains a significant challenge. Traditional rule-based or supervised learning approaches require extensive human supervision and often lack generalizability. The use of Large Language Models (LLMs) has recently emerged as a promising alternative, but their limitations become evident in complex modular architectures. This study proposes a multi-agent approach for the automatic population of modular ontologies. Each agent is an LLM guided by precise instructions and enhanced with appropriate tools, dedicated to one or more ontological modules. Our methodology combines advanced prompt engineering techniques with strategies for hallucination mitigation to ensure extractions that are both accurate and compliant with the ontology’s specifications. Our experimental setup involves extracting RDF triples from diagnostic PDF reports and activity schedules stored in a MongoDB database, aimed at the automatic population of an ADHD ontology. The results show that our multi-agent approach consistently outperforms mono-agent methods relying on a single LLM, regardless of the configuration used. We observe significant gains in precision, recall, and F1-score as well as a notable reduction in errors and hallucinations. This study demonstrates both the feasibility and effectiveness of a multi-agent architecture for the automatic population of a modular ontology
Effets de bord réversibles et monades,dans le système de présentation Slipshow
No full textInternational audienceSlipshow est un logiciel de présentation, qui se focalise sur un style de discours plus « continu » que les diapositives. Très versatile, il permet à l’auteur de la présentation de déclencher de nombreuses actions à chaque étape, voire même d’en définir lui-même. Cela pose un défi d’ingénierie : comment « inverser » l’exécution d’une étape, quand le présentateur souhaite revenir en arrière, tout en gardant un code simple, maintenable et extensible ? Dans cet article, nous verrons la solution utilisée par Slipshow, basée sur le patron de conception des monades, et son utilisation rendue aisée par le langage de programmation OCaml
Adaptive Agents in Spatial Double-Auction Markets: Modeling the Emergence of Industrial Symbiosis
No full textInternational audienceIndustrial symbiosis fosters circularity by enabling firms to repurpose residual resources, yet its emergence is constrained by socio-spatial frictions that shape costs, matching opportunities, and market efficiency. Existing models often overlook the interaction between spatial structure, market design, and adaptive firm behavior, limiting our understanding of where and how symbiosis arises. We develop an agent-based model where heterogeneous firms trade byproducts through a spatially embedded double-auction market, with prices and quantities emerging endogenously from local interactions. Leveraging reinforcement learning, firms adapt their bidding strategies to maximize profit while accounting for transport costs, disposal penalties, and resource scarcity. Simulation experiments reveal the economic and spatial conditions under which decentralized exchanges converge toward stable and efficient outcomes. Counterfactual regret analysis shows that sellers' strategies approach a near Nash equilibrium, while sensitivity analysis highlights how spatial structures and market parameters jointly govern circularity. Our model provides a basis for exploring policy interventions that seek to align firm incentives with sustainability goals, and more broadly demonstrates how decentralized coordination can emerge from adaptive agents in spatially constrained markets
Le coeur du capital: Ces travailleuses de l’ombre qui font tourner le monde
No full textInternational audienceOn croise certaines d’entre elles sans les voir : tôt le matin dans le métro, tard le soir à la sortie d’un hôtel, d’un hôpital ou de bureaux.Qui sont ces femmes qui portent à bout de bras l’économie capitaliste, depuis ses coulisses ?Elles prennent en charge les tâchesde soin, d’éducation, de ménage.Elles sont peu visibles, peu considérées, mal rémunérées,mais elles constituent pourtantle « coeur » du capital. Sans elles, pas de force de travail, pas d’économie : c’est ce qu’on appelle le travail reproductif.Cet essai écrit à quatre mains croise les apports des féminismes, de l’économie et de l’histoire des luttes sociales, pour mettre en lumière ce travail de l’ombre.Une puissante critique du capitalisme, enracinée dans l’expérience concrète de millions de personnes, qui enjoint les lecteurs et lectrices à réinventer l’organisation du travail et de la société tout entière
HC(3)As, the simplest arsadiyne
No full textInternational audience1-Arsabutadiyne (2-propynylidynearsine, HC(3)As), is efficiently produced by photolysis of propynylarsine isolated in solid argon. The observed infrared absorption spectra and predicted molecular parameters of HC(3)As and HC(3)P show significant similarities, but large differences compared to HC(3)N
Supercritical CO₂ extraction of Withania frutescens essential oils: Box-behnken RSM optimization, antifungal, antioxidant activities and molecular docking insights
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Hetero-lanthanide coordination polymers as a posteriori temperature markers
No full textInternational audienceAfter many years of studying the luminescence properties of coordination polymers based on lanthanide elements, the question now is to determine if these properties could vary with temperature. Based on the thermogravimetric analyses, it is possible to observe several steps corresponding to various phase changes (dehydration, decomposition, etc.), which could be evidenced by a change in luminescence. The five compounds studied here are based on three different ligands: 1,4-carboxyphenylboronic acid (H2cpb), tetrachlorophthalic acid (H2tcpa), and trimesic acid (H3tma). Three out of the five are based on a single emissive lanthanide, terbium or europium, and the remaining two are heteronuclear compounds based on these two lanthanides: [Tb(cpb) (cpbOH)(H2O)2]infinity (1), [Eu2(tcpa)3(H2O)6]infinity (2), [Y0.8Eu0.2(tma)(H2O)5 center dot 3.5H2O]infinity (3), [Eu0.1Tb0.9(cpb)(cpbOH) (H2O)2]infinity (4) and [Eu0.4Tb1.6(tcpa)3(H2O)6]infinity (5). Based on their thermogravimetric analyses, key temperatures were identified, at which the compounds were heated before studying their luminescence properties a posteriori. Finally, preliminary tests of dispersion in plastic matrices are conducted to observe the impact of the host matrix on the observed luminescence properties
Addressing child labor with layered interventions: a study of the PACE program’s impact on child’s schooling and work in Ethiopia
No full textInternational audienceThis study evaluates the impact of the Partnership Against Child Exploitation (PACE) program in Ethiopia, an initiative aimed at reducing child labor and increasing school attendance in vulnerable communities. The program identified a child in a family, at risk or involved in worst forms of child labor. The program’s design incorporated support to income generating activities and savings systems at the family level, educational assistance at the child level, and community awareness campaigns. We study the effectiveness of the PACE program employing a randomized controlled trial design with a large sample size and minimal attrition, enabling to causally assess the program’s impact on both schooling and work-related outcomes. We use multi-level modeling to account for the three levels of intervention (family, child and community) Our study finds that the PACE program significantly increased school attendance among rural children directly targeted by the intervention. However, the program did not impact school attendance in urban areas or among siblings and other children in rural communities. Additionally, while the program did not reduce the likelihood of child labor or the number of hours children spent working per day, it reduced the incidence of work outside the household for all children in supported families