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AI-enhanced sorting enabling direct high-purity tantalum urban mining: a novel pathway from e-waste to critical materials
No full textInternational audienceTantalum’s supply chain instability demands efficient urban mining from e-waste. Here, we present an AI-enhanced process that combines intelligent sorting with sustainable hydrometallurgy for high-yield/high-purity Ta recovery. A hybrid sorting system, cascading an interpretable convolutional neural network (CNN) with automated multi-energy X-ray transmission (MEXRT) spectroscopy, achieved 99.6 % precision and 96.9 % recall at 3000 components/hour, resolving the Ta/Nb ambiguity. Spatial activation mapping illustrated the visual sorting mechanism, facilitating feature-driven upgrading. Meanwhile, Canny edge detection and K-edge detection enabled real-time and pixel-wise spectral analysis under multi-threaded processing. Downstream, streamlined physical separation and thermodynamically guided reverse leaching selectively recovered Ta with 98.2 % efficiency under mild conditions. Advanced characterization using transmission electron microscopy and ion beam analysis revealed a quantifiable core-shell Ta/Ta2O5 structure in leached products, guiding calcination into >99.8 % pure Ta2O5. This work establishes a closed-loop urban mining framework, demonstrating how AI and tailored refining enable a circular economy for critical metals
Post-intensive care syndrome. What clinicians and researchers must know
No full textInternational audienceThe COVID-19 pandemic has highlighted intensive care as a cornerstone of modern medicine. In spite of global aging and the increase of comorbidities in the general population, a large proportion of patients survive their hospitalization in the Intensive Care Unit (ICU). Nevertheless, these positive results are challenged by the higher mortality rates than other non-critically ill populations after discharge. Moreover, there is growing evidence that ICU survivors display a high rate of mental health disorders (anxiety and depression symptoms, post-traumatic stress disorders), somatic impairment (muscle atrophy, neuropathy, and myopathy with persistent muscle weakness, chronic kidney disease, chronic respiratory failure), or cognitive impairment. Patient’s relatives also suffer from mental health disorders (anxiety and depression symptoms, complicated bereavement). All these chronic health issues significantly impair the quality of life and increase healthcare costs. Post-Intensive Care Syndrome (PICS) is a term that encompasses all these complications. The COVID-19 pandemic has highlighted PICS as a public health concern. This review summarizes the most recent findings on PICS. It addresses epidemiological data about the frequency of somatic disorders, cognitive impairment, and mental health problems in both patients and their relatives and describes the pathophysiology mechanisms underlying PICS. The review also provides insights into management experimentations and treatment interventions that have been tested so far to improve the outcome of critically ill survivors. Finally, the review proposes measures to implement PICS management in follow-up centers and a research agenda to pave the future research on this topic
A Cauchy-Piola framework for micro-based micromorphic continua
No full textInternational audienceMany results on micromorphic media can be found in the literature, where the equations of motion and the energetic foundations of the Eringen micromorphic continuum have been well established. The present paper has been devoted to the continuum modeling of a finite number of interacting, separated continua (microdomains) at the microscale, in which the strain energy has been formulated through a generalization of the Cauchy-Green deformation tensor, resulting in a degenerate metric at the considered scale, and a (6 × 6) Green-Lagrange strain tensor. The equilibrium equations have been obtained by systematically applying the method of virtual power. For one of the first time, boundary-layer conditions appear in micromorphic mechanics. The paper concludes with a discussion on the number of constitutive parameters, shown to coincide, in number, with those of classical (Cauchy) elasticity, together with the recovery of micropolar continua as a special case and wide spectrum of applications of the proposed framework. Further details concerning the algebraic expressions of the tensors involved are provided in the Appendices
Oral indomethacin modifies small intestine biofilms and host-microbe interaction mediators
No full textInternational audienceBackground and aims: Nonsteroidal anti-inflammatory drugs (NSAIDs) can cause small intestinal injury and dysbiosis. Although NSAID-induced dysbiosis is well-characterized and contributes to enteropathy, the changes in host-bacterial interactions during enteropathy remain largely unexplored. Here we assessed the expression pattern of six toll-like receptors (TLRs) and three antimicrobial peptides (AMPs) over the course of indomethacin (IND)-induced enteropathy in rats, and evaluated their correlations with inflammation and dysbiosis. In addition, we assessed for the first time the effect of IND on small intestinal mucosal biofilm structure.Materials and methods: Mucosal injury, inflammation and expression of TLR and AMP genes were evaluated at five time points following IND administration. Gut microbiota composition was determined by 16S rRNA gene sequencing. Small intestinal mucosal biofilms were visualized using fluorescent in situ hybridisation.Key findings: We found that TLR1, TLR2 and cathelicidin were upregulated, TLR5 was downregulated, whereas TLR6 and TLR9 were not altered in enteropathy. TLR4 expression showed only subtle differences, but correlated with α-defensin 5 and β-defensin 2 levels. We found several correlations between TLRs, AMPs, inflammation and gut bacteria in severe enteropathy, but in early disease stage TLR1, TLR2, TLR5 and cathelicidin expression were more strongly associated with inflammation, whereas TLR4 and defensins were more dependent on gut dysbiosis. IND treatment also caused mild damage to the mucosal microbiota biofilm.Significance: This is the first comprehensive characterization of the time-dependent changes in TLRs, AMPs and mucosal biofilm in NSAID-treated rats, which may help to identify new strategies for the treatment of enteropathy
Virtual Reality-Based HSI for a Human-Centric Systems Engineering Metaverse
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Toward sustainable transformer oil recycling: comparative efficacy of adsorbents and CFD simulation analysis
No full textInternational audienceTransformer insulating oils undergo progressive degradation due to oxidation, accumulation of aging by-products, and contamination by metallic particles. Proper regeneration of these oils is crucial to extend transformer lifespan and reduce environmental impact. This study investigates the performance of locally activated Algerian adsorbents (Illite and Maghnite) compared to commercial adsorbents (activated Bauxite and Sepiolite) for the regeneration of degraded transformer oils. The materials were evaluated for their adsorption efficiency toward acids, water, and oxidation products, as well as their ability to restore key electrical and thermalproperties. Activated Illite and Maghnite demonstrated performance comparable to commercial adsorbents, significantly reducing the acid number from 0.23 to 0.01 mg KOH/g. Illite exhibited superior reusability, maintaining regeneration efficiency over 300 cycles. Additionally, sulfur compounds were reduced from 344 to 40 ppm. Treated oils achieved a breakdown voltage of 78 kV and a dielectric dissipation factor of 0.995, closely matching new oil standards. Computational fluid dynamics (CFD) simulations were employed to assess Illite’s behavior in industrial-scale oil treatment, supporting its effectiveness as a substitute for Bauxite. The results highlight Illite’s potential as a viable, sustainable, and locally available alternative for transformer oil recycling. Nevertheless, challenges related to large-scale implementation, including material availability, cost, and process integration, remain and warrant further investigation. This study contributes to the development of environmentally responsible and economically competitive solutions for the regeneration of insulating oils using natural adsorbents.Les huiles isolantes des transformateurs subissent une dégradation progressive due à l'oxydation, à l'accumulation de sous-produits de vieillissement et à la contamination par des particules métalliques. Une régénération adéquate de ces huiles est essentielle pour prolonger la durée de vie des transformateurs et réduire leur impact sur l'environnement. Cette étude examine les performances d'adsorbants algériens activés localement (illite et maghnite) par rapport à des adsorbants commerciaux (bauxite activée et sépiolite) pour la régénération d'huiles de transformateur dégradées. Les matériaux ont été évalués en fonction de leur efficacité d'adsorption des acides, de l'eau et des produits d'oxydation, ainsi que de leur capacité à restaurer les propriétés électriques et thermiques essentielles. L'illite et la maghnite activées ont démontré des performances comparables à celles des adsorbants commerciaux, réduisant considérablement l'indice d'acide de 0,23 à 0,01 mg KOH/g. L'illite a montré une réutilisabilité supérieure, conservant son efficacité de régénération pendant plus de 300 cycles. De plus, les composés soufrés ont été réduits de 344 à 40 ppm. Les huiles traitées ont atteint une tension de claquage de 78 kV et un facteur de dissipation diélectrique de 0,995, ce qui correspond étroitement aux nouvelles normes applicables aux huiles. Des simulations de dynamique des fluides computationnelle (CFD) ont été utilisées pour évaluer le comportement de l'illite dans le traitement du pétrole à l'échelle industrielle, confirmant son efficacité en tant que substitut à la bauxite. Les résultats soulignent le potentiel de l'illite en tant qu'alternative viable, durable et disponible localement pour le recyclage des huiles de transformateur. Néanmoins, les défis liés à la mise en œuvre à grande échelle, notamment la disponibilité des matériaux, le coût et l'intégration des processus, demeurent et méritent d'être approfondis. Cette étude contribue au développement de solutions respectueuses de l'environnement et économiquement compétitives pour la régénération des huiles isolantes à l'aide d'adsorbants naturels
Gold nanoparticles–polyoxometalates composites: a comprehensive overview from synthesis and characterization to applications
No full textInternational audienceGold nanoparticles (AuNPs) have attracted attention for their unique electronic and optical properties and their wide range of applications. The development of hybrid nanoparticles by combining AuNPs with other molecules or materials is a powerful way of introducing new functions and extending their use. In particular, gold nanoparticles can be associated to organometallic complexes, biological molecules, coordination polymers or polyoxometalates (POMs), the latter being a group of soluble anionic metal oxides composed of transition metals in high oxidation states. Inorganic POMs come in a wide variety of shapes and sizes and are valued especially for their biological and catalytic properties. They are particularly interesting for the synthesis of AuNPs composites, as they can stabilize nanoparticles through electrostatic or covalent interactions and steric effects without the presence of additional surfactants, reduce gold cations by photochemical, electrochemical, or chemical reduction, or directly when used in their reduced form, and confer properties to the resulting systems. POMs can also be covalently combined with organic molecules of interest, which can in turn contribute to the functionalities of the gold nanoparticles. This review focuses on gold nanoparticles directly coated with POMs and covers their synthesis and characterization. Particular attention is also paid to their applications, including (photo)(electro)catalysis, biomedical applications (antibacterial, anticancer and anti-Alzheimer's) and their use as sensors
The impact of mine ownership on trade of metal ores
No full textInternational audienceMetals are essential to the global economy, yet traditional criticality assessments, often based solely on the geographic concentration of mining production, overlook the corporate control dimension of risk. Here, we analyzed whether ownership structures affect trade patterns in critical minerals and examined how production and corporate control diverged from 2000 to 2022. We developed a comprehensive country-level dataset using S&P Capital IQ Pro for 12 key metals and metal ores, calculated Herfindahl-Hirschman indices (HHI) for production and ownership, and statistically tested the relationship between foreign mine ownership and international trade flows using logistic and fixed-effects regressions. Finally, we built scenarios for production and ownership in 2030 to match demand estimates from the International Energy Agency (IEA). Results showed only 2%-14% of global ore trade value overlaping with existing foreign ownership ties and no statistically significant relationship between foreign mine ownership and trade flows. Additionally, clear divergences emerged between ownership and production concentration: cobalt production was highly geographically concentrated (HHI of 4602 in 2022) but had dispersed corporate ownership (HHI of 1985), and high-income countries frequently held substantial ownership stakes despite declining shares of actual production. Projected scenarios indicated continued shifts, notably reduced cobalt and lithium production shares in traditional producer countries, offset by growing Canadian and Australian ownership. Although market dynamics do not appear to be influenced by ownership structures today, corporate control remains a potential lever for supply chain disruption. This underscores the need to incorporate ownership into criticality assessments for a more comprehensive understanding of supply risks.</div
Primary School Teachers’ Media and Information Literacy: A Contrastive Study Between France and Peru
No full textInternational audienceThis qualitative study examines the implementation of Media and Information Literacy (MIL) in French and Peruvian primary schools, considering teachers’ information practices. Data collection involved individual teacher interviews (21), classroom observations (20), and student group interviews (21) in both countries. Despite contrasting national contexts, findings reveal a scarcity of MIL-focused learning activities, with information-seeking tasks being the most prevalent, often occurring outside of school hours (such as homework). While teachers acknowledge the importance of MIL, time constraints, technical and pedagogical challenges, and a lack of dedicated training were cited as significant barriers. Teachers rely heavily on self-training and personal information habits to implement MIL-related learning activities in the classroom. They struggle with information seeking for teaching purposes, such as lesson plans. Theoretically, the study highlights the need to address the research gap on teachers’ information practices. Practically, the findings shed light on the necessity of educating primary school teachers in the MIL area, taking into account the role of information in their everyday lives as well as in their jobs, and the way these information experiences shape classroom MIL implementation. Findings suggest that public policies should consider teachers’ actual ability to educate students in MIL (beyond computer equipment and how-to-use training) to reduce information inequalities