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Gilets jaunes et Anti-pass sanitaire : étude des obstacles à une coalition protestataire dans le centre de la France
No full textNational audienceThis article explores the emergence and subsequent fragmentation of the protest coalition formed by Yellow Vests and anti- health pass activists in 2021. Based on an analysis of political and strategic tensions within mobilizations in a medium- sized city in central France, it aims to understand the conditions that led to the split between the two protest groups. Considering the social characteristics and protest experiences of Yellow Vests and anti- health pass activists, it examines their distinct demands, incompatible policy preferences, and tactical disagreements.Cet article examine l’émergence puis la fragmentation de la coalition protestataire formée par des Gilets jaunes et des Anti- pass sanitaire en 2021. À partir d’une analyse des tensions politiques et stratégiques au sein des mobilisations dans une ville moyenne du centre de la France, il vise à appréhender les conditions de la rupture entre les deux groupes contestataires. À l’aune des propriétés sociales et des expériences protestataires des Gilets jaunes et des Anti- pass sanitaire, il rend compte de leurs revendications distinctes, de leurs dispositions politiques incompatibles et de leurs désaccords tactiques
Preparation of Se(IV) Aryltrifluoromethylselenide Dichlorides
No full textInternational audienceTrifluoromethylselenide dichlorides are rare selenium(IV) derivatives that have received limited attention despite their potential in organoselenium chemistry. We report a straightforward and efficient synthesis of dichloro(aryl)(trifluoromethyl)‐λ 4 ‐selanes (ArSeCl 2 CF 3 ) via chlorination of aryl trifluoromethylselenides in acetonitrile as the solvent of choice. After evaluating various chlorinating agents, sulfuryl chloride (SO 2 Cl 2 ) revealed to be very efficient in a broad scope of substrates. Complementary density functional theory calculations provided mechanistic insight, indicating that chlorination proceeds via an asynchronous concerted mechanism with an accessible activation barrier and is exergonic, readily leading to the formation of Se(IV) fluorinated compounds. In contrast, the formation of the Se(VI) tetra‐chlorinated derivative via oxidative addition of Cl 2 to the Se(IV) derivative was found to be both kinetically and thermodynamically infeasible
Faire de l'architecture rationaliste un patrimoine sans promouvoir le régime fasciste (?) Le cas de la province natale de Benito Mussolini
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Les expériences d’occupation : une gouvernance territoriale alternative ?
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The Trojan horse effect of nanoplastics exacerbates methylmercury-induced neurotoxicity during zebrafish development
No full textOger, Mathilde J L Bernay, Benoit Tessier, Emmanuel Amouroux, David Kestemont, Patrick Cornet, Valerie eng England 2025/08/10 Environ Pollut. 2025 Nov 1;384:126966. doi: 10.1016/j.envpol.2025.126966. Epub 2025 Aug 7.International audienceWhile the ability of plastic particles to transport heavy metals is well established, their Trojan horse effect on aquatic organisms remains debated, as they are suspected of facilitating the penetration of chemicals in tissues but also of reducing bioavailability and accelerating pollutant elimination. Here, we investigated the combined effects of 250 nm polystyrene nanoplastics (NPs) and methylmercury (MeHg) on zebrafish larvae over a 30-day exposure period. Larvae were exposed to 1000 mug/L NPs, 1 mug/L MeHg (MeHg1), 10 mug/L MeHg (MeHg10), or their respective combinations (Mix1 and Mix10). The presence of NPs enhanced MeHg accumulation and redirected its distribution toward the fish's head and eyes. On their own, NPs altered swimming activity, while MeHg10 induced mortality, reduced growth and diminished swimming activity. Proteomic analysis highlighted significant effects on lipid metabolism, oxidative stress, detoxification, myogenesis and catabolism. Although no light sensitivity deficits were detected through visual motor response testing, proteomic data suggested vision impairment in the mixture-exposed groups. High mortality rates were observed in Mix10-exposed fish, likely due to severe hypoactivity, which hindered feeding. This hypoactivity was linked to disrupted lipid metabolism, impaired neurotransmission, reduced ATP production, and neuroinflammation leading to neuronal degeneration. We concluded that the presence of NPs intensified MeHg neurotoxicity over a prolonged exposure, significantly increasing mortality
Development of novel sustainable lignin nanoparticles-caseinate nanocomposite films with properties for application as food packaging materials
No full textInternational audienceThe development of biodegradable and recyclable food packaging materials derived from biomass is a promising solution to mitigate resource depletion and minimize ecological contamination. In this study, lignin nano- particles (LNPs) were effectively produced from bamboo powder using an eco-friendly recyclable acid hydro- trope (RAH) strategy. A sustainable CA/LNPs nanocomposite film was then designed by incorporating these LNPs into a casein (CA) matrix. The LNPs served as nucleation templates, inducing ordered hydrogen bonding and close packing of the CA chains. The addition of 5 wt% LNPs significantly enhanced the mechanical properties of the film, with tensile strength enhanced to 21.42 MPa (219.7 % improvement) and elastic modulus rising to 354.88 MPa (220.3 % enhancement) compared to pure CA film. Notably, the resultant CA/LNPs nanocomposite film exhibited recyclable recasting characteristics, maintaining a reasonable mechanical strength even after three recasting cycles. The incorporation of LNPs also decreased the water solubility of the pure CA film from 31.65 % to 24.81 % indicating some interactions are taking place, while endowing the film with superior UV-blocking ability, achieving nearly complete absorption in the 200–400 nm range. Moreover, the inherent properties of LNPs imparted improved antibacterial and antioxidant activities to the CA/LNPs nanocomposite film. Owing to its comprehensive properties, the CA/LNPs nanocomposite film effectively extended the storage life of straw- berries. A soil burial degradation test confirmed over 100 % mass loss within 45 days, highlighting excellent degradability of the films. Therefore, the simple extraction of LNPs and the easily recovery of p-TsOH provide significant promise and feasibility for extending the developed methodologies in this work to rapidly promote the produced films in fields such as degradable and packaging materials
Rapid and precise determination of elemental impurities in pharmaceutical products by ICP-MS using combined standard addition and isotope dilution methods
No full textInternational audienceThe determination of elemental impurities in pharmaceutical products has received increased attention due to recent regulatory requirements involving the use of advanced atomic spectrometry techniques. The carbon-rich matrices of drugs and the presence of excipients make sample preparation difficult and give rise to matrix effects that considerably affect ICP-MS measurements. In this study, the sample preparation step was optimized by experimental design using two heating devices (heating blocks and microwave-assisted digestion) in presence of HNO 3 , HCl and HF. A digestion temperature of approximately 100 • C was found to achieve recoveries within the USP criteria (70-150 %) for 24 elements, with no significant difference in recoveries between the two devices. Isotope dilution (ID) was then applied for the first time to quantify 15 elemental impurities in the drug matrices. The procedure involving the addition of isotopic tracers prior to mineralization made it possible to overcome matrix effects and provided a unique sample preparation procedure regardless of the drug. The use of ID also improved measurement precision (mean RSD of 1.5 %) compared with external calibration (mean RSD of 2.3 %) or standard additions (mean RSD of 3.1 %). Recoveries ranged from 89 to 106 % for elements quantified by ID and from 80 to 110 % for those determined by standard additions. After successful validation according to USP requirements, the method was applied to different drugs. Concentrations found were below USP-authorized limits for all elements, with the exception of lead, which was present at concentrations of 0.2 μg g -1 in a hypertensive and 0.7 μg g -1 in a laxative (USP limit = 0.15 μg g -1 )
Chemical Characterisation of Inorganic Profile of Wine Obtained by Alternative Vinification in Comparison with Traditional One
No full textPré-dépôt HAL IPREM via X2HalInternational audienceThe complex dynamics between oxygen exposure, sulphur dioxide use, and wine quality are of the utmost importance in modern winemaking. While SO2 acts as an effective antiseptic and antioxidant, its excessive use raises health concerns, prompting stricter regulations (Council Regulation EC No. 1493/1999; Commission Regulation EC No. 1622/2000) and increasing interest in natural alternatives. In this context, Bioma SAdeveloped plant-based additives derived from vineyard by-products rich in phenolic compounds to replace SO2 in vinification. This study has evaluated the impact of these additives on the inorganic elemental composition of Sangiovese wines, comparing traditional sulphite-based vinification with the Bioma-based alternative. Using triple quadrupole ICP-MS, 23 elements were quantified and analysed via ANOVA and principal component analysis (PCA). The results revealed significant effects of the vinification protocol and ageing method on key elements such as Mn, Rb, Sr, Ni, and As. Importantly, all toxic elements, Pb (≤5.9 µg/L), Cd (≤0.3 µg/L), and As (≤12.1 µg/L), remained well below EU safety thresholds. PCA further highlighted distinct elemental profiles between traditional and Bioma wines. These findings confirm that Bioma additives enable the production of wines with reduced sulphur content and compliant elemental safety, supporting their potential as sustainable, health-conscious alternatives in modern oenology
Feather keratin hydrolysates as sustainable binders for high-density fiberboards
No full textInternational audienceThis study evaluates the potential of feather keratin hydrolysates, obtained through ultrasound-assisted alkaline hydrolysis at low and high temperatures, as sustainable binders for high-density fiberboards (HDFs). The performance of keratin-based adhesives was compared with that of current binders, namely urea-formaldehyde (UF) and soy protein isolate (SPI). Adhesives were applied at a content of 12%. Additionally, a second formulation using 15% keratin hydrolysate extracted at high temperature (KHT 15) was tested to assess the influence of binder loading. The mechanical and physical properties of the HDF panels—including modulus of rupture, modulus of elasticity, internal bond strength, screw withdrawal resistance, thickness swelling, water absorption, and surface wettability—were systematically evaluated. Both keratin formulations outperformed SPI and matched or surpassed UF in key performance indicators. Among them, keratin extracted at high temperature exhibited superior mechanical strength and moisture resistance, which may be related to the formation of stronger disulfide bonds. In particular, KHT 15 increased internal bond strength by 74% compared to UF and 96% compared to SPI, and reduced 24 h water absorption by 36% and 58% respectively. Keratin-based panels also retained higher water contact angles after 60 s, demonstrating improved surface hydrophobicity. Although keratin extracted at high temperature at 12% fulfilled the EN 622-5 standard for dry-use panels, increasing the content to 15% enabled compliance with the requirements for humid conditions, with TS below 30%. These results position keratin hydrolysates, particularly at high temperature, as viable, bio-based alternatives to synthetic and food-derived adhesives in engineered wood composites aligned with circular bioeconomy principles
Bilan du suivi du stock de saumon sur la Nivelle: Synthèse 1994-2024
No full textUn programme scientifique de suivi des poissons diadromes de la Nivelle est mis en œuvre depuis 1984. Il se déroule grâce à un large partenariat qui lie INRAE avec l’association MIGRADOUR, la Fédération pour la Pêche et la Protection des Milieux Aquatiques des Pyrénées Atlantiques, l’AAPPMA Nivelle – Côte Basque, l’Office Français pour la Biodiversité et la Communauté d’Agglomération Pays Basque. INRAE, MIGRADOUR et l’AAPPMA de la Nivelle assurent la collecte des données aux deux installations de piégeage d’Uxondoa et d’Olha. Le programme bénéficie du soutien financier de nombreux partenaires, dont en particulier l’Agence de l’Eau Adour-Garonne, l’Union Européenne (fonds FEDER) et la Fédération Nationale de la Pêche. L’objectif de ce programme était initialement l’évaluation à long terme d’une population de saumon sur un cours d’eau colonisés par cette espèce dans le sud de son aire de répartition et ce focus sur le saumon demeure.La Nivelle fait partie du réseau international des « Index Rivers » du Conseil International pour l’Exploitation de la Mer (CIEM). Elle émarge à un observatoire de recherche en environnement « Poissons diadromes dans les Fleuves Côtiers » (DiaPFC) au sein duquel elle est associée à 3 autres cours d’eau observatoires (l’Oir et la Bresle en Normandie et le Scorff en Bretagne). L’ORE DiaPFC est le fruit d’un partenariat étroit entre l’Office Français pour la Biodiversité et INRAE. Depuis le début des années 80, le programme de suivi de la population de saumon collecte des données à différents stades du cycle biologique de l’espèce : adultes anadromes lors de leur montaison grâce aux deux stations de contrôle d’Uxondoa et d’Olha. juvénile de l’année (tacon) en rivière avec la réalisation d’un échantillonnage en automne par pêche à l’électricité sur 22 stations distribuées sur la Nivelle et ses affluents. reproduction hivernale en décembre et janvier où les frayères de saumon sont dénombrées sur le cours principal de la Nivelle et ses affluents.L’évolution des retours d’adultes dans la Nivelle est marquée par une césure majeure intervenant au début des années 2000 (2002-2003), avec une réduction très significative des retours de castillons. C’est également à cette période que débute une diminution de la taille des adultes, plus marquée chez les castillons que chez les saumons de printemps. Les castillons, qui constituent la fraction largement majoritaire parmi les adultes anadromes, est donc celle qui a évolué globalement le plus négativement. Cette évolution s’accompagne d’une réduction de la part relative des castillons dans les retours. Avec seulement 4 individus estimés, 2024 est la pire remontée de castillons jamais observée alors que celle des saumons de printemps est au dessus dans la moyenne (44 individus).A la différence des retours d’adultes, l’abondance des juvéniles (tacons de l’année observés en automne) reste stable au cours du temps, bien que fluctuant fortement d’une année sur l’autre. La réduction de la quantité d’œufs pondus par les femelles adultes, intervenue au début des années 2000, n’a donc pas eu à ce jour d’effet significatif sur le renouvellement des générations sur le statut de conservation de la population. On notera cependant que la très faible densité d’œufs déposés dans la Nivelle en 2023 a produit la plus faible densité globale de tacons 0+ en 2024.Du suivi depuis 4 décennies de la population de saumon de la Nivelle émerge un bilan contrasté. Les capacités de production de juvéniles en eau douce (survie de l’œuf au tacon) se sont améliorée et la récente ouverture des parties les plus amont du réseau situées en Espagne devrait contribuer à accentuer cette évolution positive. Dans le même temps, la capacité à convertir les juvéniles produits en adultes anadromes de retour dans la Nivelle s’est dégradée. La résultante de ces 2 évolution opposées est plutôt négative si on la juge à l’aune des retours d’adultes et de la dépose d’œufs qui stagnent à des niveaux faibles depuis le début des années 2000.Dans ce contexte général, les toutes dernières années sont plus particulièrement préoccupantes, avec des taux retours très bas et successivement pour les 3 dernières cohortes, qui se traduisent au cours des 3 dernières années par des retours de castillons et des déposes d’œufs les plus faibles jamais observés. Les années qui viennent seront cruciales pour savoir si ce point bas est temporaire ou s’il marque l’entrée dans une période encore plus difficile pour la population de saumon de la Nivelle.Face à cet avenir incertain, qui sera influencé par les effets potentiellement négatifs du changement climatique en cours, l’extension significative des zones colonisables par le saumon sur le bassin consécutive à l’arasement du barrage d’Urrutinea en 2023 est un réel atout. Mais cela doit s’accompagner d’une réduction maximale de toutes les sources de mortalités maitrisables