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Pathway from Molecular Strain to Crystal Domains and Cracks in Layered Co–W Charge-Transfer Materials
No full textInternational audienceSwitchable materials hold promise for diverse applications, but their performance is often compromised by cracking or decomposition during phase transitions. These problems are significant in molecular materials, affecting not only the deterioration of crystallinity but also the crystal growth. Herein, we present a comparative synchrotron-based crystallographic investigation on two thermal and photoswitchable cobalt-octacyanidotungstate assemblies, [{Co(isoquinoline)4}3{W(CN)8}2]·2EtOH (1) and Rb[Co(3-cyanopyridine)2{W(CN)8}]·H2O (2), both of which feature two-dimensional layered network by cyanido-bridging between cobalt and tungstate. Compound 1 undergoes a gradual transition with minor structural changes due to flexible π–π interactions. In contrast, compound 2’s rigid cyanido-bridged network, reinforced by Rb+ cations, causes abrupt volume contraction and pronounced reorganization. This rigidity induces significant strain, as evidenced by increased mosaicity and cracks during phase transitions. Our findings illustrate that while both systems share a two-dimensional layered structure, the nature of the molecular connectivity crucially governs the molecular deformations and the degree of induced strain during structural reorganization. These insights emphasize the importance of optimizing interlayer interactions and lattice rigidity for tailoring the mechanical integrity and reversibility of electronic states in switchable molecular materials with enhanced durability
Comprehensive review of per- and polyfluoroalkyl substances (PFAS) in groundwater: occurrence, ecological impacts, analytical techniques, and remediation strategies
No full textInternational audiencePer-and polyfluoroalkyl substances (PFAS) represent an extensive class of synthetic compounds known for their persistence due to extremely stable carbon-fluorine bond, widely detected in aquifers worldwide (e.g.: PFOA 5650.2 ng/L and PFOS 203.3 ng/L, on average). Most of these compounds pose significant acute or chronic health risks. Besides this, the literature suggests that contamination by at least one PFAS is expected in all locations. Furthermore, PFAS plumes tend to be larger than those associated with hydrocarbons and volatile chlorinated organic compounds, and their remediation poses greater challenges due to limited understanding of their behavior, transformations, and remediation mechanism. Given the extent of the occurrence of these chemicals and their adverse effects, the need to develop detection and measurement techniques, in addition to remediation technologies, is evident. This review systematically examines literature published between 2014 and 2025, on Web of Science, Scopus, and Google Scholar databases, to address these limitations. It discusses the extent of PFAS contamination, their ecological effects, and the key mechanisms influencing their mobility and retention in subsurface environments. It also critically evaluates the latest advances in analytical techniques for PFAS detection and highlights emerging strategies for effective remediation in-situ, providing a base for further research and development
Machine learning et logements collectifs : quand l’algorithme rencontre la transition énergétique
No full textInternational audienceDepuis le début des années 2020, le secteur immobilier français est impacté par la hausse des coûts de construction et les nouvelles réglementations environnementales (RE 2020). Dans ce contexte, la valeur verte, définie comme l’augmentation du prix d’un bien immobilier liée à celle de ses performances énergétiques, devient un enjeu clé. Cet article, réalisé en collaboration avec le Groupe Vivialys, propose une méthode d’estimation de cette valeur à l’aide d’outils issus du machine learning sur des bases de données ouvertes portant exclusivement sur des logements collectifs. Les résultats menés lors de cette collaboration montrent que les logements plus performants énergétiquement bénéficient d’une revalorisation mesurable, offrant ainsi un outil d’aide à la décision pour les acteurs du marché immobilier
Establishing assessment criteria for soil bioindicators: insights from case studies in Europe
No full textInternational audienceThe new EU Soil Strategy aims to restore soil health across Europe by 2050, requiring policy-relevant indicators with robust assessment criteria to control and monitor its achievement. Despite the importance of biological conditions for soil health, few EU Member States have currently established criteria (e.g., target or threshold values) for evaluation of monitoring data. Our study examines the challenges and opportunities in developing such criteria based on the normal operating ranges of bioindicators in the context of soil units (i.e., homogenous soil texture and land use). Leveraging on national case studies across Europe, we find that for most bioindicators criteria could not be defined, due to data insufficiency and environmental bias. Only in France could normal operating ranges be established for earthworms, for some soil units. We identify priorities for the development of robust assessment criteria: (1) Harmonization of evaluation units and definitions, to minimize disparities in current soil texture and land use classifications between Member States, that complicate comparability of evaluation across Europe; (2) Inclusion of climatic-region specific thresholds/targets in addition to land use and soil texture; and (3) Standardization of protocols to reduce the observed variability in methods for sampling and data aggregation. As a temporary solution to optimize monitoring sampling efforts, guidelines for dealing with data deficiencies and pseudo-replication are proposed. On the longer term, our findings highlight the importance of integrated data systems and standardised frameworks for monitoring bioindicators to evaluate progress towards achievement of the EU soil health targets
Predicting Real-Life Creativity Using Resting State Electroencephalography (P9-3.014)
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Ancillary X‐Type Ligand Effects in Alkyne and Diyne Metathesis with Fluoroalkoxy Molybdenum Alkylidynes
No full textInternational audienceSeven hexa‐ and nonafluoroalkoxy‐substituted 2,4,6‐trimethylbenzylidyne molybdenum(VI) complexes [MesC≡Mo{OC(CF3)n(CH3)3–n}2(X)] (MoFn‐X, n = 6, 9; X = imidazolin‐2‐imide, phosphoraneimide, or siloxide) have been synthesized via salt metathesis from fluoroalkoxy precursors [MesC≡Mo{OC(CF3)2CH3}3)] (MoF6) and [MesC≡Mo{OC(CF3)3}3)] (MoF9). Structural characterization by X‐ray diffraction and NMR spectroscopy confirm the successful incorporation of the ancillary X‐type ligands. In two cases, the reaction with 3‐hexyne leads to the formation of molybdenacyclobutadiene (MoCBD) complexes of the type [(C3Et3)Mo{OC(CF3)3}2X] (X = NImtBu, OSi(OtBu)2Ph), characterized by single‐crystal X‐ray diffraction, revealing distorted square‐pyramidal geometries with coplanar orientations of the ancillary ligands relative to the metallacyclic MoC3 unit. The incorporation of N‐donor ligands is found to be detrimental for catalytic alkyne and diyne metathesis, whereas the siloxy‐functionalized MoF9‐OSi(OtBu)2Ph complex exhibits high activity in alkyne metathesis and excellent selectivity in converting sterically demanding pentadiynes (RC≡CC≡CMe, R = iPr3Si, Ph3Si, 2,4,6‐Me3C6H2, 2‐iPrC6H4) into symmetrical triynes (RC≡CC≡CC≡CR) and 2‐butyne (MeC≡CMe). These findings provide insights into the critical electronic and steric factors governing diyne metathesis and underscore the critical role of siloxide ligands in promoting efficient diyne disproportionation catalysis
Flow-Induced Lateral Migration and Droplet Segregation in Flexible Rectangular Microchannels
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Quantifying the short-term mortality effects of wildfire smoke in Europe: a multicountry epidemiological study in 654 contiguous regions
No full textInternational audienceBackground: Fine particulate matter (PM2·5) from wildfire smoke could be more harmful to human health than that from other sources. Evidence of the short-term association between wildfire-related PM2·5 and mortality in Europe remains sparse, leading to uncertainties in the fire-related PM2·5 mortality burden.Methods: In this retrospective, multicountry epidemiological study, we used the EARLY-ADAPT database to obtain daily mortality records in 654 contiguous subnational regions from 32 European countries, representing a population of 541 million individuals. We combined these data with daily estimates of fire-related and non-fire-related PM2·5 from the System for Integrated Modelling of Atmospheric Composition model during 2004-22. Regional and pooled associations between daily fire-related PM2·5 and all-cause and cause-specific mortality were quantified using quasi-Poisson regression. We compared deaths attributable to fire-related PM2·5 using relative risks (RRs) specific to fire-related PM2·5 versus total PM2·5.Findings: Our study data included 95⸱3 million daily deaths for all-cause mortality, 19⸱5 million daily deaths for cardiovascular mortality, and 3⸱9 million daily deaths for respiratory mortality from Jan 1, 2004, until the latest available year in each country. Pooled cumulative (lags 0-7) RRs associated with a 1 μg per m3 increase in fire-related PM2·5 were 1⸱007 (95% CI 1⸱004-1⸱010) for all-cause mortality, 1⸱009 (1⸱006-1⸱013) for cardiovascular mortality, and 1⸱013 (1⸱008-1⸱019) for respiratory mortality. RRs were larger for fire-related PM2·5 than for non-fire-related PM2·5. Using RRs for total (fire-related and non-fire-related) PM2·5 underestimated the fire-related PM2·5 attributable mortality by 93%.Interpretation: Associations with all-cause and cause-specific mortality were larger for fire-related compared with non-fire-related PM2·5. Assuming wildfire PM2·5 has the same effect as total PM2·5 substantially underestimates the mortality burden of wildfire smoke
La solution sinthomatique : vers une clinique pragmatique des sinthomes de suppléance
No full textIn the era of the non-existence of the Other, where social bonds are marked by the fragmentation of common discourses and the imperative of jouissance, psychoanalytic clinical practice faces subjective dynamics that elude classical psychopathological categories. This work examines different forms of sinthomatic solutions as modes of suppletion allowing the subject to knot RSI without relying on the Name-of-the-Father. By integrating Lacanian psychoanalysis, the history of psychopathology, and contemporary theories of social bonds, we explore the transition from a structuralist approach to new configurations of subjectivity. Through the analysis of modalities of suppletion, this research seeks to outline a pragmatic clinic of sinthomes that transcends the classical neurosis-psychosis opposition. It thus proposes a binary opposition more suited to the clinic of our time: sinthomatic-structures vs. non-sinthomatic-structures. The analysis of the logic behind Marina Abramović’s artistic work illustrates how art can function as a sinthome, offering a singular solution to contemporary social bond impasses.À l’époque de l’inexistence de l’Autre, où le lien social est marqué par la fragmentation des discours communs et l’impératif de jouissance, la clinique psychanalytique est confrontée à des dynamiques subjectives qui échappent aux catégories classiques de la psychopathologie. Cette thèse interroge les différentes formes de solutions sinthomatiques, comme modes de suppléance permettant au sujet de nouer RSI sans recours au Nom-du-Père. En croisant les apports de la psychanalyse lacanienne, de l’histoire de la psychopathologie et des théories du lien social contemporain, nous explorons la transition de l’approche structuraliste vers les nouvelles figures de la subjectivité. À travers l’analyse des modalités de suppléance, cette recherche vise à dégager une clinique pragmatique des sinthomes de suppléance, qui dépasse l’opposition classique névrose-psychose. Ainsi, elle propose une opposition binaire plus adaptée pour la clinique de notre époque : structures sinthomées - structures non-sinthomées. L’analyse de la logique de l’œuvre artistique de Marina Abramović illustre comment l’art peut fonctionner comme sinthome, proposant une solution singulière aux impasses du lien social contemporain
Penser le risque et l'adaptation en contexte d'incertitude : L’estuaire de la Loire à l'épreuve de l'élévation du niveau marin
No full textIn the context of climate change, sea level rise is one of the major challenges for coastal and estuarine areas. Positioned at the interface between marine and fluvial influences and concentrating numerous planning, economic, and environmental stakes, estuaries are particularly vulnerable to fluviomarine hazards. Amid growing uncertainties, the Loire estuary, along with its alluvial plain and adjacent marshes,is no exception to this reality as a vast expanse of low-lying areas. This thesis examines the construction of risk and adaptation in the Loire estuary at a time when local discussions on these issues are emerging. The study aims to understand the socio-spatial representations of stakeholders and to explore territorial governance in order to consider adaptation strategies for the estuarine interface. This research relies on a mixed-methods approach, combining a quantitative survey of the local population with a set of qualitative methods involving other estuary stakeholders. The finding highlight the low level of individual concern regarding risks and offer various explanations, such as attachment to one’s place of residence or perceptions of the landscape. The study also emphasizes the specific nature of risk exposure in the estuary, underscoring the need for estuarine co-management. The analysis of adaptation solution preferences highlights the importance of designing a patchwork of solutions, with a focus on promoting “flexible” measures. Finally, this thesis examines the estuary’s overall adaptive capacity and trajectory.Dans le cadre du changement climatique, l’élévation du niveau marin constitue l’un des défis majeurs pour les zones côtières et estuariennes. À l’interface des influences marines et fluviales, concentrant de nombreux enjeux d’aménagement, économiques ou naturels, les estuaires sont vulnérables aux aléas fluviomarins. Dans un contexte d’incertitudes grandissantes, l’estuaire de la Loire, ainsi que sa plaine alluviale et ses marais adjacents, n’échappent pas à cette réalité en tant que vaste ensemble de zones basses. Cette thèse questionne la construction du risque et de l’adaptation dans l’estuaire de la Loire à l’heure où émergent des réflexions locales sur ces questions. Ce travail cherche à comprendre les représentations socio-spatiales des acteurs et à interroger la gouvernance territoriale afin d’envisager l’adaptation de l’interface estuarienne. Pour ce faire, cette recherche s’appuie sur une méthodologie mixte, utilisant une enquête quantitative auprès de la population et un ensemble de dispositifs qualitatifs auprès des autres acteurs de l’estuaire. Les résultats abordent le faible concernement des individus face aux risques et apportent différents faisceaux d’explications comme l’attachement au lieu de vie ou le rapport au paysage. Les travaux appuient également sur les particularités de la mise en risque de l’estuaire amenant à la nécessité d’une cogestion estuarienne. L’étude des préférences en matière de solution d’adaptation souligne l’importance de concevoir un patchwork de solutions en valorisant les mesures “flexibles”. Enfin, cette thèse porte un regard sur la capacité et la trajectoire d’adaptation générale de l’estuaire