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Therapeutic plasma exchange in amatoxin associated acute liver failure–results from the multi-center Amanita-PEX study
No full textInternational audienceBackground: Amatoxin-related acute liver failure (AT-ALF) carries high mortality without liver transplantation (LTX). While therapeutic plasma exchange (PEX) might improve LTX-free survival in other ALF cases, its role in AT-ALF is unclear. Clinical practice varies, and, given the rarity of this ALF entity, the feasibility of conducting a randomized controlled trial to investigate PEX in AT-ALF is more or less impossible.Methods: The Amanita-PEX study is a multi-center, international, retrospective study analyzing patients with AT-ALF from 2013 to 2024. The primary outcome was 28-day LTX-free survival (composite endpoint: death or LTX) after ALF diagnosis.Results: The study included 111 patients from 25 centers: 82 received standard-of-care (SOC), and 29 received at least one PEX-session. PEX and SOC-groups were comparable at baseline, but 76% of PEX- vs. 58% of SOC-patients developed hepatic-encephalopathy (HE) grade ≥ 2 (p = 0.021). While the primary outcome of 28-day LTX-free survival in all patients was not different between the SOC and PEX-groups, in the subgroup of patients with maximal HE grade ≥ 2, LTX-free survival was 19.1% (n = 8/42) in the SOC group, while it was 36.4% (n = 8/22) in patients receiving adjunctive PEX (Gehan-Breslow-Wilcoxon-p = 0.041, Log-Rank-p = 0.060). PEX was independently associated with reduced risk of the combined endpoint death or liver transplantation within 28 days from inclusion in patients with HE grade ≥ 2 (HR 0.37, 95%-CI 0.19-0.73, p = 0.004). After propensity-score-matching, LTX-free survival was 28% in the SOC- and 52% in the PEX group (Gehan-Breslow-p = 0.036; Log-Rank-p = 0.035).Conclusions: In this real-world study, adjunctive use of PEX was associated with increased LTX-free-survival in patients with AT-ALF and HE grade ≥ 2
Environmental and Ecological Monitoring with Biodegradable Technologies
No full textInternational audienceThe emergence of a new family of wireless biodegradable sensors marks a groundbreaking leap in ecological and environmental sensing. These biodegradable devices can collect a wide range of data in agriculture, climate research, forestry, water management, and biodiversity protection. Manufactured primarily from environmentally safe transient materials for sensing and data transmission, these systems undergo controlled degradation after use, minimizing environmental electronic waste. Here, a critical review of key aspects in the development and application of biodegradable sensors is performed for ecological and environmental monitoring. First, the different materials utilized in the development of biodegradable environmental monitoring devices and their applications are explored. The relevant degradation mechanisms, including hydrolysis, oxidation, photodegradation, and micro‐organism action are examined as a function of environmental conditions. Then compatible and non‐toxic fabrication techniques are investigated for building biodegradable sensors, emphasizing their scalability and potential for mass production. Finally, system‐level considerations are discussed for sustainable powering of these devices, ensuring efficient operation while maintaining environmental sustainability. By surveying a broad spectrum of applications and ongoing advancements, it is argued that biodegradable sensors have a transformative potential in advancing sustainable, widespread, and cost‐effective ecological and environmental monitoring solutions
Beyond-Diagonal Dynamic Metasurface Antenna
No full textNational audienceDynamic metasurface antennas (DMAs) are an emerging technology for next-generation wireless base stations, distinguished by hybrid analog/digital beamforming capabilities with low hardware complexity. However, the intrinsic coupling between meta-atoms is fixed by static waveguide or cavity structures in existing DMAs, which fundamentally constrains the achievable performance. Here, we introduce reconfigurable intrinsic coupling mechanisms between meta-atoms, yielding finer control over the DMA’s analog signal processing capabilities. This novel hardware is coined “beyond-diagonal DMA” (BD-DMA), in line with established BD-RIS terminology. Considering realistic hardware constraints, we derive a physics-consistent system model revealing (correlated) “beyond-diagonal” programmability. We also present an equivalent formulation with (uncorrelated) “diagonal” programmability. Based on the latter, we propose a general and efficient mutual-coupling-aware optimization algorithm. Physics-consistent simulations validate the performance enhancement enabled by reconfigurable intrinsic coupling mechanisms in BD-DMAs. The BD-DMA benefits grow with the mutual coupling strength
Fabrication et caractérisation de résistances à base de nanofils de silicium
No full textNational audienceThis article presents practical work on manufacturing technologies and the characterization of resistors made from silicon nanowires synthesized using the vapor-liquid-solid method with gold as a catalyst. The resistors produced using two manufacturing technologies are observed using confocal optical microscopy and scanning electron microscopy, then electrically characterized by I-V measurements based on their geometry and the doping rate of the nanowires. Measuring the electrical resistance allows to deduce the average resistivity of the nanowires and the access resistances at the interface between the nanowires and the electrode.This course is proposed to second-year Master's students or equivalent studying nanotechnology. Cette formation est proposée à des étudiants de 2 e année de Master ou équivalent suivant un enseignement en nanotechnologies.Cet article présente des travaux pratiques sur les technologies de fabrication et la caractérisation de résistances fabriquées à partir de nanofils de silicium synthétisés par la méthode vapeur liquide solide utilisant l’or comme catalyseur. Les résistances issues de deux technologies de fabrication sont observées par microscopie optique confocale et microscopie électronique à balayage, puis caractérisées électriquement par mesures I-V en fonction de leur géométrie et du taux de dopage des nanofils. La mesure de la valeur de la résistance électrique permet de déduire la résistivité moyenne des nanofils et les résistances d’accès à l’interface entre les nanofils et l’électrode. Cette formation est proposée à des étudiants de 2 e année de Master ou équivalent suivant un enseignement en nanotechnologies
Electronique imprimée : une ouverture aux nouvelles technologies
No full textNational audiencePrinted electronics is developing and enabling new applications, particularly in flexible and 3D electronics. In this context, which is closely linked to our research work and benefits from semi-industrial equipment, we felt it was important to raise awareness of these new technologies and new knowledge among electronics students. We offer training courses tailored to different electronics courses and to the expectations of students and teachers, which provide a more precise overview of the potential of these technologies, their industrial and consumer applications, and the challenges to be overcome. The aim is to enable students to learn how to use printing machines so that they can understand the constraints and possibilities of manufacturing simple electronic circuits. In practical terms, students are required to use an inkjet printing machine and a screen-printing machine to produce metal tracks and double-layer resistors used as strain sensors. The training is completed with an electrical characterization of the manufactured components. Several cohorts of students from different backgrounds have been involved. For each of these courses, the practical and theoretical content of the training is adapted to the target audience. The acquisition of the skills developed is assessed by a multiple-choice exam for short courses, or by writing a summary report.L’électronique imprimée se développe et permet d’adresser de nouvelles applications en particulier en électronique souple ou 3D. Dans ce contexte fortement lié à nos travaux de recherche, et bénéficiant de matériels semi-industriels, il nous a semblé important de sensibiliser les étudiants en électronique à ces nouvelles technologies et nouveaux savoirs. Nous proposons des formations adaptées à différents parcours en électronique et aux attentes des étudiants et enseignants, qui permettent d’acquérir une vision plus précise des potentialités de ces technologies, de leurs applications industrielles et grand public, ainsi que des défis à relever. L’objectif est de permettre aux étudiants de se former sur des machines d’impression, de façon à appréhender les contraintes et les possibilités de fabrication de circuits électroniques simples. Concrètement, les étudiants sont amenés à manipuler sur une machine d’impression de type jet d’encre, ainsi qu’une machine de sérigraphie pour la réalisation de pistes métalliques, ainsi que de résistances bicouches utilisées comme capteurs de déformation. La formation est finalisée par une caractérisation électrique des éléments fabriqués. Plusieurs cohortes d’étudiants issus de formations différentes ont été impliquées. Pour chacun de ces parcours, le contenu de la formation, pratique et théorique est adapté en fonction du public concerné. L’acquisition des compétences développées est évaluée par un examen de type QCM pour les formations courtes, ou la rédaction d’un rapport de synthèse
Report on technological obstacles and drivers
No full textThis brief report explores the technological and technical dimensions of coastal rewilding, emphasizing the historical, cultural, and technical factors shaping coastal intertidal environments. Technology is defined not only as applied scientific knowledge but also as a sociotechnical system embedded in cultural and management contexts. Historically, European coastlines have been transformed through extensive engineering – such as dike construction, drainage, and land reclamation – illustrating how technology shaped intertidal ecosystems mostly from the 16th and 17th centuries until nowadays. Examples like Dutch hydraulic engineering and Acadian polderization in Nova Scotia demonstrate transnational knowledge transfer. Coastal rewilding, considered as the reverse of reclamation, represents a new technological and ecological paradigm, ranging from passive recovery, trophic rewilding to active rewilding strongly embedded with managed realignment. These approaches differ in technical intensity, from low-tech natural regeneration to highly engineered restoration. Nevertheless, all kind of practices face site-dependent challenges related to erosion, sediment dynamics, and legacy infrastructures. Coastal rewilding thus embodies both technological and socio-ecological experimentation, seeking to balance human intervention with natural processes. Such rewilding practices and projects must often address the “coastal squeeze,” a climate-induced constraint on habitat migration caused by sea defenses and shoreline artificialization, underscoring the intertwined histories of technology, ecology, and adaptation.This report will thus examine the relationship between coastal rewilding and managed realignment as complementary strategies for reducing shoreline artificialization and adapting to climate change. Managed realignment – defined as the deliberate repositioning or removal of coastal defenses – has evolved since the 1980s into a key soft-engineering and nature-based solution across Europe. Although terminology and objectives vary by country, it generally aims to restore intertidal habitats, enhance flood resilience, and compensate for historical habitat loss. The RECOSEA database identifies 277 European projects illustrating a wide spectrum of technical interventions, from controlled tidal exchange and partial dike breaching to complete defense removal and inland retreat (Andreu-Boussut and Chadenas, 2025). These practices collectively represent gradients of active coastal rewilding, encompassing both technical and ecological complexity. While over 60,000 hectares of intertidal habitats have been restored for the eight investigated European countries, this remains marginal compared to past reclamation losses. Remaining challenges concern balancing habitat restoration with freshwater wetland preservation, ensuring social acceptability, and integrating diverse conservation, engineering, and adaptation objectives in various and heterogeneous European contexts. This section of the report has been extensively published beyond the only technical aspects in de la Vega-Leinert et al. (2025, in press)The final section applies the Technology Readiness Level (TRL) framework to assess the maturity of coastal rewilding practices across REWRITE’s eight European Demonstrator Sites. Adapted from the EU Horizon scale, the TRL approach measures progress from conceptual development (TRL 1–3) to operational implementation and scaling-up (TRL 7–9). Coastal rewilding maturity depends on the extent of scientific understanding, the number and scale of demonstration projects, and institutional recognition of benefits associated to such practices. The analysis reveals varying readiness levels: high in the Essex Estuaries Complex (DM3) and Scheldt Estuary (DM5) (TRL 7–8), medium in Gyldensteen Coastal Lagoon (DM1) and the Wadden Sea (DM2) (6–7), and lower in southern and Atlantic sites (4–5) in Loire Estuary (DM6), Ria de Aveiro (DM7) and Cadiz Bay (DM8). Despite increasing implementation, rewilding faces technical obstacles such as sediment deficits, dike constraints, agricultural legacies, and vegetation recovery capabilities. However, drivers including sediment nourishment, adaptive dike management, low-intensity grazing, and species reintroduction foster ecosystem recovery. The TRL framework thus provides a structured tool to monitor progress and guide future coastal restoration strategies
Le retour groupé des bandits multi-bras pour aider les réseaux LoRaWAN
No full textInternational audienceL'essor de l'IoT ces dernières années a conduit au déploiement massif de dispositifs connectés, rendant les réseaux IoT plus denses. Afin d'optimiser la transmission et de limiter la congestion dans ces réseaux denses, des algorithmes de gestion adaptative du débit de données ont été mis en place, comme celui utilisé dans le protocole LoRaWAN. L'utilisation d'algorithmes basés sur l'apprentissage par renforcement, en particulier les bandits manchots, a été étudiée. Cependant, la limitation du cycle d'utilisation réduit les performances de ces algorithmes dans les réseaux denses jusqu'à 15%. Cet article vise à proposer une solution pour pallier ce problème lié à la limitation du rapport cyclique, en prenant la technologie LoRa comme cas d'étude. Un effort particulier a été fait sur la consommation d'énergie, et la fonction de récompense a été modifiée afin d'économiser l'énergie tout en garantissant la qualité de service. Les performances sont évaluées grâce à notre simulateur J-LoRaNeS, basé sur le langage Julia
Seven years of research on snow avalanches in Nunavik, northern Quebec, Canada: hazard and vulnerabilities
No full textpaper in proceedings of the conference "SNOW2025"International audienceIn Nunavik (northern Quebec, above 55°N), over the past two centuries, Inuit territorial organization has experienced a profound spatial reconfiguration. From the dispersion of Inuit nomadic camps, the way of life gradually changed with the establishment of trading and commercial posts; since 1950s structured settlement of Inuit communities is done in 14 villages. With rapid population growth, villages are still expanding. Until recently, snow avalanches in Nunavik had seldom been documented. However, ongoing research highlights that short steep slopes are prone to snow avalanches, both in village surroundings and in remote areas. To improve our understanding of snow avalanches, a network of automatic cameras monitors snow avalanches since winter 2017-2018. Slopes were selected based on geomorphologic investigations. Over the last seven winters, more than 600 snow-avalanche deposits have been identified and their paths delineated. Runout distances vary according to two distinct regimes: winter (from November to April) and spring (May-June). Weather data were analyzed to identify the range of triggering factors. There is both inter-and intra-winter variability in snow cover conditions (duration, thickness). Topographic analyses of avalanche slopes identify potential source areas for snow avalanches as well as runout distances, where infrastructures are found in some instances
Classification des concepts convoqués par les étudiant·e·s dans le débat sur la transition énergétique. Étude de cas de cas auprès d’étudiant·e·s d'une ENS
No full textInternational audienceThe energy transition is a major challenge for humanity, involving both technoscientific and societal issues. To enable citizens to participate in this debate in an informed manner, training programmes that take into account the concepts used by those concerned must be put in place. This article aims to identify what students know about the subject and to analyse this knowledge using a theoretical framework inspired by the specific theory of two worlds.La transition énergétique est un enjeu majeur pour l’humanité où s’entremêlent questions technoscientifiques et sociétales. Pour permettre aux citoyen·ne·s de participer à ce débat de manière éclairée, des formations qui prennent en compte les concepts convoqués par les personnes concernées doivent être mises en place. Cet article vise à identifier ce que les étudiant·e·s savent sur le sujet et à analyser ces connaissances à l’aide d’un cadre théorique inspiré par la théorie spécifique des deux monde
Osteopathy educators' and researchers' perspectives on artificial intelligence in academia: A cross-sectional study
No full textInternational audienceBackground: Artificial intelligence (AI) is increasingly being integrated into healthcare education and research, yet little is known about how AI is perceived within osteopathy. To the best of our knowledge, this is the first cross-sectional study to examine AI perspectives specifically among osteopathic educators and researchers, providing fresh insights into technology adoption within this healthcare discipline. Methods: A cross-sectional survey was conducted between December 2023 and February 2024 among osteopathic educators and/or researchers through snowball sampling. The survey collected data on AI-related knowledge, usage in educational and research contexts, attitudes toward AI, perceived risks, and necessities challenges. Principal Component Analysis (PCA) was used to validate the structure of the survey. Demographic factors such as age, gender, occupation, and academic qualifications were analysed in relation to scores. Results: 190 respondents from 18 countries completed the survey. Participants demonstrated positive attitudes toward the role of AI in education and research, but acknowledged limited proficiency in its use. Usage of AI was higher among younger, male participants, with AI primarily used for personal organisation and research. Concerns about AI included risks of bias, over-reliance on technology, and potential replacement of human judgment. Participants with educational roles expressed fewer concerns about AI's risks compared to those outside of education. Knowledge of AI was not correlated with demographic factors, but attitudes and concerns about risks varied with age. Conclusion: Osteopathic educators and researchers view AI as a beneficial tool for teaching and research, but face challenges in its effective implementation due to concerns about technology replacing human expertise and biases. Training, institutional support, and ethical guidelines are essential to foster the responsible integration of AI in osteopathy. Implications for practice: AI is underutilised in osteopathic education and research despite positive attitudes towards its potential. Educators are less concerned about AI risks, positioning them as key facilitators of responsible assimilation. Institutional policies should provide clear AI usage guidelines while addressing ethical and validity concerns. AI should support, not replace, human expertise, ensuring critical thinking remains central in education and research. The study protocol was prospectively registered online with the Open Science Framework on November 29, 2023 (Registration DOI: https://doi.org/10.17605/OSF.IO/QEYWG)