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Microplastics characterization in indoor environments : technical challenges
No full textInternational audienc
Nighttime Vertical Gradients of O3 and NO in Forested Regions Show Soil Emissions of NO
No full textInternational audienc
Goodness-of-fit testing for the stationary density of a size-structured PDE
No full textWe consider two division models for structured cell populations, where cells can grow, age and divide. These models have been introduced in the literature under the denomination of 'mitosis' and 'adder' models. In the recent years, there has been an increasing interest in biology to understand whether the cells divide equally or not, as this can be related to important mechanisms in cellular aging or recovery. We are therefore interested in testing the null hypothesis where the division of a mother cell results into two daughters of equal size, against the alternative hypothesis where the division is asymmetric and ruled by a kernel that is absolutely continuous with respect to the Lebesgue measure. The sample consists of i.i.d. observations of cell sizes and ages drawn from the population, and the division is not directly observed. The hypotheses of the test are reformulated as hypotheses on the stationary size and age distributions of the models, which we assume are also the distributions of the observations. We propose a goodness-of-fit test that we study numerically on simulated data before applying it on real data
Study of micro-signals: proposed analysis methodology based on data from the Lille Poison Control and Toxicovigilance Center
No full textInternational audienc
ENTRE MYTHE ET PHARMACIE : PEUT-ON CROIRE AU REISHI ?
No full textInternational audienceBetween myth and pharmacy: can we trust Reishi?Ganoderma lucidum (Reishi/Lingzhi) is a flagship species of traditional Asian medicines and is increasingly marketed worldwide as an “adaptogenic” dietary supplement. However, the taxonomic accuracy and scientific validity of products sold under this name remain questionable. We conducted a literature survey (PubMed, 2010–2025) and a taxonomic reassessment of ITS sequences deposited in GenBank as G. lucidum (n = 814), complemented by our own taxonomic and pharmacochemical studies. Although 69% of publications on Ganoderma claim to investigate G. lucidum, the main research topics concern its purported pharmacological properties: immunomodulatory and anticancer effects (34%), metabolic and cardiovascular disorders (12%), neuroprotection and anti-aging (3%). These activities are commonly attributed to bioactive metabolites such as polysaccharides, triterpenes and phenolic compounds. However, only 0.5% of the published sequences actually match G. lucidum sensu stricto, mostly of European origin. The vast majority correspond to closely related Asian species, mainly G. sichuanense (= G. lingzhi), for which chemical and biological data remain limited. In total, at least 27 different species are marketed or studied under the name “Reishi”.Our results highlight that morphology alone cannot ensure the authenticity, composition or expected effects of Ganoderma-based supplements. Genetic authentication should become a standard requirement for both scientific studies and industrial products. Regulatory frameworks for Reishi must rely on accurate species identification to guarantee product quality and consumer safety.Le Reishi (Ganoderma lucidum), champignon emblématique des médecines traditionnelles asiatiques, connaît un essor commercial majeur en tant que complément alimentaire dit « adaptogène ». Toutefois, la fiabilité des produits vendus sous ce nom reste discutée. Nous avons conduit une analyse de la littérature scientifique (PubMed, 2010-2025) et une révision taxonomique des séquences ITS déposées dans GenBank sous l’appellation G. lucidum (n = 814), complétées par nos propres travaux en taxonomie et pharmacochimie. Si 69 % des publications sur Ganoderma prétendent étudier G. lucidum, ces recherches se concentrent principalement sur ses effets pharmacologiques : immunomodulation et anticancéreux (34 %), maladies métaboliques et cardiovasculaires (12 %), neuroprotection et vieillissement (3 %). Ces propriétés sont attribuées à divers métabolites bioactifs (polysaccharides, triterpènes, composés phénoliques). Néanmoins, seules 0,5 % des séquences publiées correspondent réellement à G. lucidum sensu stricto, majoritairement européen. La très grande majorité relève en réalité d’espèces asiatiques proches, notamment G. sichuanense (= G. lingzhi), pour lesquelles les données chimiques et biologiques demeurent lacunaires. Ainsi, au moins 27 espèces différentes sont impliquées sous le nom « Reishi ».Nos résultats soulignent l’insuffisance des critères morphologiques pour garantir l’identité et l’activité des produits commercialisés. Une authentification génétique systématique des souches étudiées ou utilisées industriellement est indispensable. Une réglementation du marché du Reishi doit s’appuyer sur une identification précise des espèces afin d’assurer la qualité et la sécurité des consommateurs
Optimisation of mechanical performance in composite pressure vessels with nongeodesic paths under thermomechanical loading and unequal openings
No full textInternational audienceThis study presents a novel methodology for the multi-objective parametric optimization of a nonsymmetrical filament-wound composite vessel subjected to thermo-mechanical loading. Due to the vessel's unequal polar openings, a nonuniform fiber angle distribution is required along the cylindrical section. The proposed approach incorporates both geodesic and non-geodesic fiber paths, accommodating the asymmetry in polar openings through cross-linear modeling of the helical layers across the domes and the cylindrical region.To achieve an innovative and weight-efficient design, a multi-objective optimization problem was formulated. The optimal radii of the polar openings and the composite layer thicknesses were determined to enhance the vessel's thermomechanical performance. Thermal loading, particularly at high operating temperatures, is identified as a critical factor due to its potential to induce structural degradation.A specialized iterative algorithm was developed to perform the optimization, integrating a thermomechanical module, an optimization module, and a custom Python script. The Multi-Island Genetic Algorithm (MIGA) was employed to solve the optimization problem. Test cases were evaluated using two commercially available composite materials.</div
Mechanical behavior and mechanisms behind PVA modified expansive soil
No full textInternational audienc
How COVID-19 related policies reshaped organic aerosol source contributions in Central London
No full textInternational audienceParticulate matter (PM) poses both health and climate risks. Understanding pollution sources is therefore crucial for effective mitigation. Positive Matrix Factorization (PMF) of Aerosol Chemical Speciation Monitor (ACSM) data is a powerful tool to quantify organic aerosol (OA) sources. A year-long study of ACSM data from London's Marylebone Road monitoring station during the COVID-19 pandemic provides insights into the impact of lockdown and the Eat Out To Help Out (EOTHO) scheme, which offered support to the hospitality during the pandemic, on PM composition and OA sources. Five OA sources were identified including hydrocarbon-like OA (HOA, traffic-related, 11% to OA), cooking OA (COA, 20%), biomass burning OA (BBOA, 12%), more-oxidized oxygenated OA (MO-OOA, 38%), and less-oxidized oxygenated OA (LO-OOA, 21%). Lockdown significantly reduced HOA (-52%), COA (-67%), and BBOA (-41%) compared to their pre-COVID levels, while EOTHO increased COA (+38%) significantly compared to the post-lockdown period. However, MO-OOA and LO-OOA were less affected, as these primarily originated from long-range transport. This research has highlighted the importance of commercial cooking as a significant source of OA (20%) and PM1 (9%) in urban areas. The co-emission of BBOA with COA observed in Central London demonstrates a similar diurnal cycle and response to the EOTHO policy, indicating that cooking activities might be currently underestimated and contribute to urban BBOA. Therefore, more effort is required to quantify this source and develop targeted abatement policies to mitigate emissions as currently limited regulation is in force.</div
Rigidity of one-dimensional point processes via optimal transport
No full textWe investigate rigidity phenomena in one-dimensional point processes. We show that the existence of an transport map from a stationary lattice or the Lebesgue measure to a point process is sufficient to guarantee the properties of Number-Rigidity and Cyclic-Factor. We then apply this result to non-singular Riesz gases with parameter , defined in infinite volume as accumulation points of stationarized finite-volume Riesz gases. This includes, for , the well-known one-dimensional Coulomb gas (also called Jellium plasma, or the one-component 1D plasma)
Simulations numériques de la dispersion de particules due au trafic de camions sur des pistes de chantiers de construction
No full textInternational audienceSimulations numériques de la dispersion de particules due au trafic de camions sur des pistes de chantiers de constructio