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A Novel Compact Hierarchical Deep Convolutional Neural Network Architecture for Faulty Switch Detection and Localization in Power Converters
No full textInternational audienceThis paper introduces a hierarchical fault diagnostic framework based on Convolutional Neural Network (CNN) models to identify, localize, and classify Open Circuit Faults (OCFs) in Cascaded H-Bridge (CHB) power converters. The framework is organized in three stages: overall health detection, fault localization at the phase level, and switch/module fault identification. Two hierarchical topologies are investigated. In a 3-level CHB, the final stage performs switch-level localization, since each phase leg consists of a single H-bridge. In a 7- level CHB, the concept extends to module-level localization, where each module is considered as a complete MOSFET unit. Key contributions include the development and testing of multiple classifiers, namely a 2-class system health classifier, a 3-class phase-localization classifier, and switch/modulelocalization classifiers depending on the CHB topology. The proposed models achieved high prediction accuracy, with the 2-class classifier reaching 99.98% and the switch-localization classifiers in the 3-level CHB exceeding 95%. In the 7-level case, a hierarchical approach combining CNN-based phase localization with a rule-based module-localizer reached 100% module-level accuracy with an average inference time of 2.687ms and no trainable parameters. Finally, the framework was quantitatively benchmarked against conventional 1-D CNN, 2-D CNN, Fusion CNN, and classical machine learning methods (k-NN, Decision Tree, LDA, Naive Bayes). The comparative analysis highlights the trade-offs in accuracy, complexity, and real-time suitability, demonstrating the scalability and practical relevance of the proposed hierarchical approach. The methodology was validated using experimental and simulated data, including spectrograms generated by short-time Fourier transform (STFT) analysis of both healthy and faulty system signals
In-situ Polymerization of (Acrylamide/bisacrylamide)/bentonite Composites and their Application for Dye Removal
No full textInternational audienceThe environment is severely harmed by wastewater released from the textile industry. A few of the contaminants detected in these waters, including surfactants and dyes, have proved to be recalcitrant to standard physico-chemical processes and non-biodegradable. Current techniques of remediation still unsuccessful, and their toxicity in treated samples may result in significant health problems. This study focuses on the preparation of modified bentonite-based composites (P1 and P2) for the removal of methylene blue (MB) dye. The influence of several variables, including pH and dye solution concentration, was investigated. The equilibrium period for the adsorption of (MB) on P2 is 180 min. The kinetic studies of (MB) adhere to the pseudo-second-order model, while the Freundlich model describes the adsorption isotherm. The adsorption capacity of (MB) onto P2 is 192.30 mg g-1. Temperature positively influences the adsorption of (MB) by P2. The enthalpy values reveal the physisorption of this process
Subjects and Sojourners: A History of Indochinese in France. By Charles Keith. University of California Press, 2024. 383 pp. ISBN: 9780520396852
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Biological Flora of Britain and Ireland: Polygonatum multiflorum *
No full textInternational audienceThis account presents information on all aspects of the biology of Polygonatum multiflorum (L.) All. (Asparagaceae), Solomon's Seal, that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of Britain and Ireland: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation. Polygonatum multiflorum is a rhizomatous, clonal perennial herb found in Britain and Ireland primarily in forests, but also in hedgerows and shaded grasslands. The native range consists of much of temperate Europe, extending into western Asia, and is typically associated with nutrient‐rich, moist to well‐drained substrates. The species is a characteristic component of semi‐natural woodland understorey flora, often co‐occurring with other shade‐tolerant species, such as Mercurialis perennis and Anemone nemorosa . The flowers of P. multiflorum are pendulous, tubular, and creamy‐white with green tips, arranged in axillary clusters along the arching stem. They are primarily pollinated by long‐tongued bees and bumblebees. The resulting dull blue berries are dispersed by birds, contributing to the plant's spread across suitable habitats. Vegetative reproduction via rhizome extension is also common, leading to more or less distinct shoot clusters. The species is relatively unpalatable to herbivores due to the presence of steroidal saponins, though it is sometimes browsed by deer and by insects such as the specialized Solomon's‐seal sawfly ( Phymatocera aterrima ). It is also susceptible to fungal infections, which cause rust diseases. Recent studies have focused on the genetic fitness of populations under habitat fragmentation, on climate change effects on the species' phenology and on the vegetative and generative reproductive strategies that determine its dispersal dynamics. Historically, Polygonatum multiflorum has been valued in herbal medicine for its purported wound‐healing and anti‐inflammatory properties. P. multiflorum is often associated with ancient woodland. While this species is currently not at risk of extinction, woodland management practices, habitat fragmentation, and climate change might cause population declines or range contraction
How does the invasion of forests by Rhododendron ponticum disrupt the transformation of carbon in soils?
No full textInternational audienceInvasive alien plants can alter the ecosystem functions and soil health. Here, we investigate the impact of Rhododendron ponticum on the processes involved in the transformation of carbon in forest ecosystems. The hypotheses relating to its impacts are based on three pathways: (1) a modification of abiotic conditions leading to lower soil temperature and moisture, (2) the input of recalcitrant litter limiting microbial activity, and (3) an intensification of the impacts over time (12–63 year invasions). We assess this function using several indicators measuring degradation rates (k), stabilization factors (S), microbial activity (BR) and oxidizable carbon (POXC). We show that R. ponticum modifies the microclimate of invaded soils, but these changes have no direct effect on the carbon transformation function, which is more influenced by its litter input. The accumulation of recalcitrant litter leads to an average thickness increase twice as high in invaded sites. The magnitude of these impacts also depends on the context, in particular the duration of the invasion and the composition of the forest canopy composition. Organic matter decomposes more slowly in the early stages of invasion, but rates return to levels comparable to invaded sites after 30 years. Conversely, microbial activity increased at the beginning of the invasion and then declined as the invasion age progresses. These results suggest a long-term adaptation of microbial communities and underline the importance of integrating the temporal dimension into the assessment of the effects of invasive alien plants on soils
Histamine H3 Receptor as a target for alcohol use disorder: challenging the predictability of animal models for clinical translation in drug development
No full textInternational audienceThere is an important need to advance medication development for alcohol use disorder (AUD). BP1.3656B, a highly potent and selective histamine H3 receptor inverse agonist/antagonist, has been developed. Preclinical studies revealed high affinity, good pharmacokinetic profile, good brain penetration, and favorable safety. BP1.3656B reduced alcohol drinking and alcohol-seeking behavior in rodents. Phase I studies revealed good tolerability/pharmacokinetic in humans. Positron emission tomography revealed high brain occupancy in humans. Based on this favorable profile, two trials were conducted in subjects with AUD. In non-treatment seekers, BP1.3656B had no impact on intravenous alcohol self-administration (IV-ASA). A randomized clinical trial testing three doses of BP1.3656B versus placebo in treatment-seekers with AUD showed no reduction of heavy drinking days. Collective results illustrate the challenges inherent to clinical translation of AUD therapies, and reinforce the use of Phase IIa human laboratory paradigms as an important tool to de-risk translation of innovative drug targets for AUD
Ultrafiltration-based recovery of kraft lignin from black liquor for depolymerization purposes
No full textInternational audienceLignin, the most abundant aromatic biopolymer on Earth, represents a promising renewable resource for sustainable production of bio-based chemicals and energy carriers. However, in the pulp and paper industry, the majority of the 70 million tons of lignin annually generated in kraft black liquor remains underutilized due to its complex composition. This study explores ultrafiltration (UF) as a purification strategy to recover lignin fractions suitable for enzymatic depolymerization. Softwood black liquor was treated using six polymeric membranes (polyethersulfone, regenerated cellulose) with molecular weight cut-offs of 30, 10, and 5 kDa. UF achieved high lignin retention (>95%) across all membranes, while simultaneously rejecting 70–80% of sugars, indicating the presence of lignin–carbohydrate complexes (LCCs). Structural analyses by 31 P NMR and gel permeation chromatography confirmed that LCCs contributed to elevated apparent molecular weights and influenced membrane performance. An acid precipitation pre-treatment cleaved ether-linked carbohydrates, reducing lignin molecular weight by ~40% and improving UF selectivity. Among the tested configurations, the 5 kDa PES membrane proved most effective, combining high retention with favorable permeability and flux recovery after cleaning. These findings provide new insights into LCC-driven separation mechanisms and identify UF conditions enabling the production of purified lignin fractions compatible with enzymatic depolymerization, thereby supporting the development of integrated and sustainable lignin valorization routes in future biorefineries
Constructing 2-dimensional Lubin-Tate formal groups over Z p (I)
No full textInternational audienceIn this paper, we construct a class of 2-dimensional formal groups over Zp that provide a higher-dimensional analogue of the usual 1-dimensional Lubin-Tate formal groups, then we initiate the study of the extensions generated by their pn-torsion points. For instance, we prove that the coordinates of the p infinity-torsion points of such a formal group generate an abelian extension over a certain unramified extension of Qp, and we study some ramification properties of these abelian extensions. In particular, we prove that the extension generated by the coordinates of the p-torsion points is in general totally ramified. (c) 2025 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
Assurance emprunteur : première vague de sanctions sur les côtes bancaires ! À propos des quatre décisions de la DGCCRF des 1er et 15 octobre 2025
No full textInternational audienceDepuis le 1 octobre 2025, une première vague de sanctions émanant de la Direction générale de laconcurrence, de la consommation et de la répression des fraudes a touché les côtes bancaires françaisesconcernant plusieurs banques ayant distribué des assurances emprunteurs. Ainsi, des amendesadministratives ont été infligées au CIC-Est, à la Caisse régionale de Crédit Agricole Paris IDF, à la BredBanque Populaire et à la société Caisse d’Épargne et de Prévoyance Île-de-France, ces quatreétablissements bancaires ayant largement dépassé le délai légal de dix jours ouvrés pour répondre auxdemandes de substitution d’assurance emprunteur émanant des assurés.Source(s) commentée(s) -- DGCCRF, 1er oct. 2025, décision c/ CIC-Est, sanction de 196 000 € : l’accès à cette décision aété bloqué sur les sites officiels -- DGCCRF, 15 oct. 2025, décision c/ Crédit agricole d’Île-de-France, sanction de 323 518 € :l’accès à cette décision a été bloqué sur les sites officiels -- DGCCRF, 15 oct. 2025, décision c/ Bred-Banque Populaire, sanction de 298 000 € : décisionconsultable sur https://lext.so/kt91UH -- DGCCRF, 15 oct. 2025, décision c/ Caisse d’épargne d’Île-de-France, sanction de 80 000 € :l’accès à cette décision a été bloqué sur les sites officiel
Greater Thermophilisation in Communities of Juveniles Than Adults in Temperate European Forests
No full textInternational audienceAim Warming of the climate system is increasing the dominance of warm‐adapted species, a process referred to as thermophilisation. In forests, adult trees in the forest canopy experience warmer daytime summer conditions than juveniles in the understorey, but they are less susceptible to warming. These differences can result in differing thermophilisation rates between adults and juveniles. Here, we quantify for the first time the long‐term thermophilisation of tree species in temperate European forests, comparing adults with juveniles. Location Europe. Methods We calculated the thermophilisation of adults and juveniles of forest tree species using layer‐specific climatic data, species cover and occurrence data from 2202 resurveyed vegetation plots recorded twice between 1933 and 2017 and located across 12 European countries. We inferred species' thermal profiles from species distribution maps matched to gridded open‐air temperature (proxy for above‐canopy macroclimate) for adults and to below‐canopy microclimate temperature for juveniles. Results The thermophilisation rate in the juvenile layer was seven times higher than in the adult tree layer. The thermophilisation rates of both adults and juveniles were primarily driven by gains in relatively warm‐adapted species and a concurrent, but less strong, decrease in cold‐adapted species. Conclusion The compositional change in favour of more warm‐adapted species was mainly driven by gains in warm‐adapted species. The magnitude of these responses and the influencing variables were different in the community of adults and juveniles. These results underpin the importance of separately quantifying the responses of individuals throughout their life cycle to improve our ability to understand the impacts of environmental change on forest biodiversity and composition and apply targeted management actions