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Coupling of electrochemical systems with nature-based solution for wastewater treatment: A comprehensive review to evaluate the synergy, efficacy and applicability
No full textInternational audienceThis paper critically reviews for the first time electrochemical-assisted nature-based solution (NBS) systems applied for wastewater treatment. Such coupling could be a more sustainable response to address the water issues through the Sustainable Development Goals (SDGs) from the United Nations. Eight electrochemical/NBS systems combinations have been identified in the literature: (i) electro-coagulation (EC)/electro-oxidation (EO)-constructed wetland (CW), (ii) microbial fuel cell (MFC)-CW, (iii) bio-electrochemical system (BES)-CW, (iv) electrokinetic (EK)-phytoremediation (PR), (v) MFC/EC-vermi filtration (VF), (vi) electro-Fenton (EF)-algal pond (AP), (vii) electrochemical disinfection (ED)/ICME-soil infiltration, and (viii) SI/green wall (GW). The main principles, mechanisms and parameters have been critically reviewed, as well as the synergies gained through such coupling. Still, challenges remained to be solved. The matrix effect during electrochemical treatment could induce toxicity of the treated solution before NBS remediation, which remained underexplored. In addition, the mechanisms involved in the NBS systems are still not fully clarified, meaning that the process control is not easy to implement due to difficulties in getting predictive modelling. A few recommendations concern the need to develop suitable electrochemical designs, such as microfluidic devices, particularly adapted to low-conductivity effluent to avoid the addition of supporting electrolyte. Future work should experimentally validate low-energy electrosorption-based processes in combination with NBS
Influence of screw dislocations on stacking order in graphite
No full textInternational audienceThis work examines how screw dislocations disrupt ideal stacking in graphenic materials, using a machine learning interatomic potential to model screw dislocation dipoles within different periodic cells. A novel tool is developed to assess local interlayer registration to quantify and visualise regions exhibiting stacking order. Using molecular dynamics simulations, we demonstrate that single screws exhibit greater stability in rhombohedral stacking compared to AA stacking, whereas double screws exhibit greater stability in Bernal AB stacking. The investigation reveals several mechanisms through which the ideal stacking configuration is achieved despite the presence of screw dislocations, including shearing, bond length distortion, and buckling. Furthermore, an upper threshold for the density of screw dislocations is calculated, beyond which ideal stacking cannot be realised, potentially offering an explanation for certain forms of turbostratic carbon. The findings also indicate that single screw dislocations hinder Bernal AB stacking in graphite, whereas double screw dislocations support Bernal stacking, which is significant for understanding the formation processes of graphite.</div
Areas susceptible to desertification in Brazil: An approach based on the frequency of annual aridity classes
No full textInternational audienceThe expansion of arid lands is one of the most critical environmental threats of the century, driven by climate change and unsustainable human activities. In Brazil, recent climatic shifts suggest an expansion of arid and semi-arid zones beyond the traditionally vulnerable Northeast region. While prior research has emphasized long-term climatological trends focused in that region, this study adopts non-stationary approaches to examine year-by-year aridity class frequencies from 1961 to 2020 across the entirety of Brazil. It also distinguishes the relative influence of precipitation (P) and potential evapotranspiration (PET) on observed aridity index (AI) changes. Our results reveal an expansion of roughly 30 % of dryland conditions across Brazil over the past 30 years, extending beyond the traditionally semi-arid Northeast into the Southeast, and an emerging hotspot in the Pantanal, potentially linked with larger scale South American aridization trends. The increasing annual frequency of arid and semi-arid classifications, particularly in emerging zones, suggests a persistent shift towards drier climates. This pattern seems to be driven primarily by declining P and secondarily by rising PET (temperature). By analyzing annual frequencies, we uncover a creeping aridity process, which directly converses with updated desertification risk assessments and climate adaptation strategies in Brazil, such as the ‘Brazilian Action Plan to Combat Desertification and Mitigate the Effects of Drought’
Long-term monitoring of coastal boulder deposits on Banneg Island: A good proxy for detection of extreme oceanic storms off West Brittany (France)
No full textInternational audienceCoastal boulder deposits (CBD) provide relevant information on coast-erosion wave events, -defined here as extreme events combining energetic storm wave and high spring tide level-, and are crucial for understanding giant storm wave impacts on coastal geomorphology. Banneg Island, located off the coast of Brittany (France), faces Atlantic storm waves that are not attenuated in this highly exposed area. This island is characterised by CBD resulting from the erosion of western cliffs, that have accumulated at the top of the island as a result of storm wave/inudation processes. These accumulations have been subjected to topo-morphological survey for the last two decades (using GNSS measurements from 2005-2012, and using UAV-based measurements since 2012). Hydrodynamic conditions (wave and water levels) were also analyzed. We used these data to analyse the frequency of extreme events over the last 20 years. The results show a good relationship between boulder transport (measured as volume of boulder displacement) and the frequency of extreme events inundating the island. Over the survey period, we found significant interannual variability in the occurrence of these extreme events, depending on winter weather conditions. This storminess variability is significantly correlated with the WEPA climatic index, calculated on the 3 winter months (December to February). Finally, the results from Banneg Island were compared with long-term monitoring carried out in other sectors along the coast of Brittany, to build a comprehensive picture of storminess and its impact on coastal change in Brittany over the last 20 years
Quantum vs. semiclassical description of in-QGP quarkonia in the quantum Brownian regime
No full textInternational audienceIn this work, we explore the range of validity of the semiclassical approximation of a quantum master equation designed to describe the dynamics in a quark gluon plasma at various temperatures, in the quantum Brownian regime. We perform a comparative study of various properties, e.g. the charmonia yield, of the Wigner density obtained with the Lindblad equation and with the associated semiclassical Fokker-Planck equation. The semiclassical description is found to reproduce with a remarkable accuracy the results obtained through the full quantum description. We show that, to a large extent, this can be attributed to the non-unitary components of the dynamics that result from the contact of the subsystem with the thermal bath, leading to a rapid classicalization of the subsystem
Advanced practice nurses for fall incidence prevention in robust very old adults: protocol for the APN-FIT hybrid randomized controlled trial
No full textInternational audienceBackgroundFalls in older adults represent a major cause of disability and a pivotal indicator of the transition from robustness to frailty. Implementing large-scale prevention programs remains challenging because it requires the mobilization of extensive skills and human resources. In France, Advanced Practice Nurses (APN) are emerging as key actors in primary care, with the potential to provide multimodal, preventive, and patient-centered follow-up for older adults.MethodsThe APN-FIT trial (Advanced Practice Nurses for Fall Incidence prevenTion in robust very old adults) is a hybrid type 1, multicenter, randomized, open-label, superiority trial conducted in seven medical centers in the Pays de la Loire region, France. The study will assess whether a 12-month, personalized, multimodal follow-up by APN reduces fall incidence among robust participants aged ≥ 80 years (Clinical Frailty Scale ≤ 3). A mixed-methods implementation study and a cost-utility analysis will be performed. A total of 386 participants will be randomized 1:1 after an initial comprehensive geriatric assessment (CGA). The intervention group will be followed by APN at 1, 3, 6, 9, and 12 months. Primary and secondary outcomes, including intrinsic capacity domains, will be reassessed at 12 months.DiscussionWe expect that APN follow-up will reduce fall incidence and delay transitions to pre-frailty or impaired mobility. This pragmatic hybrid trial will provide evidence on the clinical, economic, and implementation impact of APN-led fall prevention in community-dwelling very old adults.Trial registrationThis study has been registered on clinicaltrials.gov, NCT06617806, registration date 2024-09-26
Les Voyageurs français en Chine aux XVIIe et XVIIIe siècles
No full textLes voyageurs français en Chineaux XVIIe et XVIIIe siècles, éditions l'Harmattan, collection Recherches Asiatiques, Paris, 2007Contrairement aux idées reçues, la rencontre de la France avecla Chine remonte à plus loin que ce qu’on imaginait. En effet,dès 1685, Louis XIV envoie en Chine six missionnaires jésuites,tous parés du titre ‘’Mathématiciens du Roi’’. Ceux-cis’introduisent à la Cour Impériale et découvrent peu à peu lalangue et la civilisation chinoises. Ils transmettent ainsi lestechniques et le savoir entre Versailles et le Palais Impérial. Cependant,si leur prosélytisme sous couvert d’aide scientifiquen’atteint pas les buts espérés, ces Pères deviennent les ‘’médiateursculturels’’ entre la France et la Chine. Si leurs connaissancessur l’Empire Céleste accumulées au fil des ans, puis transmises en France, éclaireront, au Siècle des Lumières, Montesquieu, Voltaire et bien d’autres, en revanche, il y avait assurément un fossé entre la Chine vue par les missionnaires et la Chine telle qu’elle était réellement. Découvrons donc, sans prétention à l’exhaustivité, à travers lestémoignages des Français du Siècle des Lumières, les caractéristiquespropres à nos deux civilisations au cours d’une époque charnière pour chacune d’elle. En Chine, comme en France, on assiste pendant cette époque aux derniers feux de l’Ancien Régime où jaillissent les premières étincelles d’un monde nouveau, qui, à travers un siècle et demi de bouleversements, allait devenir celui que nous connaissons actuellement
GATE 10 Monte Carlo particle transport simulation: II. Architecture and innovations
No full textInternational audienceOver the past years, we have developed GATE version 10, a major re-implementation of the long-standing Geant4-based Monte Carlo application for particle and radiation transport simulation in medical physics. This release introduces many new features and significant improvements, most notably a Python-based user interface replacing the legacy static input files. The new functionality of GATE version 10 is described in the part 1 companion paper (Sarrutet al2025 arXiv:2507.09842). The development brought significant challenges. In this paper, we present the solutions that we have developed to overcome these challenges. In particular, we present a modular design that robustly manages the core components of a simulation: particle sources, geometry, physics processes, and data acquisition. The architecture consists of integrated C++ and Python codes. This framework allows for the precise, time-aware generation of primary particles, a critical requirement for accurately modeling positron emission tomography, radionuclide therapies, or prompt-gamma timing systems. We present how GATE 10 handles complex Geant4 physics settings while exposing a simple interface to the user. Furthermore, we describe the methodological solutions that facilitate the seamless integration of advanced physics models and variance reduction techniques. The architecture supports sophisticated scoring of physical quantities (such as Linear Energy Transfer and Relative Biological Effectiveness) and is designed for multithreaded execution. The new user interface allows researchers to script complex simulation workflows and directly couple external tools, such as artificial intelligence models for source generation or detector response. By detailing these architectural innovations, we demonstrate how GATE 10 provides a more powerful and flexible tool for research and innovation in medical physics. This paper is not intended to be a developer guide. Its purpose is to share with the research community in-depth explanations of our development effort that made the new GATE 10 possible
Imaginaires et gestes de la mort en cendres: une recherche-création pour explorer la dispersion hors des cimetières et des jardins du souvenir
No full textInternational audienceIn this article, based on an ongoing research-creation project, we take a look at practices that are emerging outside the traditional funeral framework : the scattering of human ashes in “natural” spaces not set aside to accommodate human remains. Because these practices invoke questions of space, gesture, communication and symbolism, and touch on intimate and creative dimensions of the experiences of the bereaved in new environments and situations, we need to rely on open and receptive methods of investigation, collection and analysis in order to identify and study these new developments. We present an experimental method combining the artistic and scientific practices, developed in several complementary stages. Firstly, a collection of micro-narratives of experiences of dispersal, gathered anonymously via an online form that is still open to this day, which will give us access to people's subjective perceptions and reflections, and allow us to explore what is currently being done and thought within individual and family contexts. An initial classification by theme has been proposed, categorizing the range of ways we have of dealing with the dead, and questioning what these ways say about loss and absence, but also about our capacity to reinvent the practice of mourning. Secondly, workshops sessions in which we re-enacted a number of these collected micro-narratives in order to articulate perceptions that had been passed over in silence in the micro-narratives themselves and reflect on the ways these practices are shared in vivo. While the ultimate aim of this ongoing research-creation project is to add to the body of scientific knowledge around death and ashes (practices, imaginaries, gestures, impact on design, site management, public policy, citizenship, etc.), to achieve this, it aims to use creative methods of collection and analysis, that can best reveal the full breadth of these experiences. In this article, we share some of the initial methodological and scientific results of these exploratory approaches.Dans cet article basé sur une recherche-création en cours, nous nous intéressons à des pratiques qui naissent en dehors du cadre funéraire traditionnel : les dispersions de cendres humaines en espaces naturels non aménagés. Parce qu’elles touchent à la fois à l’espace, aux gestes, à la communication et à la symbolique, parce qu’elles relèvent de l’intime, mais aussi de la créativité des endeuillés dans des environnements et des situations inédits, nous devons, pour identifier et étudier les évolutions, nous appuyer sur des modes d’enquête, de collecte et d’analyse ouverts, réceptifs. Nous présenterons une méthode expérimentale entre arts et sciences développée en plusieurs étapes complémentaires. Premièrement, un recueil de micro-récits anonymes d’expériences de dispersion, récolté via un formulaire en ligne encore ouvert à ce jour, nous aide à accéder à des représentations et perceptions confidentielles, à découvrir ce qui se fait et ce qui se pense actuellement dans le cadre individuel et familial. Un premier classement a été proposé par thèmes, nous informant sur nos manières de faire avec les morts, sur ce que ces manières traduisent de la perte et de l’absence, mais aussi de notre capacité à réinventer la pratique du deuil. Deuxièmement, l’explicitation d’interprétations actionnées (re-enactment), performées et commentées d’un certain nombre de micro-récits, effectuées lors de temps de workshop, révèlent des perceptions passées sous silence dans les micro-récits et la manière dont elles se partagent in vivo. Si l’objectif de cette recherche-création en cours est à terme d’enrichir les connaissances scientifiques sur la mort en cendres (pratiques, imaginaires, gestes, impact sur la conception, la gestion des lieux, les politiques publiques, la citoyenneté…), elle vise pour y parvenir, dans le recueil et l’analyse du corpus, à emprunter des méthodes créatives à même de révéler au mieux toute l’épaisseur de ces expériences. C’est avec des premiers résultats méthodologiques et scientifiques que nous partageons dans cet article certaines de ces voies exploratoires