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Homo- and hetero-dinuclear CpFe and CpRu complexes of a 1,2,4-triazo-le-bis-Cp ligand with anticancer potential
No full textInternational audienceA homo- and a hetero-dinuclear organometallic complex, [(Cp)Fe(Cp)-CH(Tz)-(Cp)M(Cp)] (M = Fe (3a), Ru (3b); Cp- = cyclopentadienyl, Tz = 1,2,4-triazole), were prepared from carbinol precursors [(Cp)Fe(Cp)-CH(OH)-(Cp)M(Cp)] (M = Fe (2a), Ru (2b), and 1,2,4-triazole. Complexes 3a-b were characterized by 1H and 13C NMR spectroscopy, mass spectrometry (MS), and elemental analysis. The X-ray crystal structure of 3a reveals two ferrocenyl units, whereas 3b exhibits two Fe/Ru mixed-occupancy metal sites in a 1:1 ratio, along with disorder in the pendant Cp units in both structures. These findings are consistent with the MS data, which clearly show the [M]+ ion for 3a (Fe/Fe) and 3b (Fe/Ru), but no Fe/Fe or Ru/Ru species for 3b. The antiproliferative activities of 3a and 3b were evaluated against HeLa, MCF-7, and HT-29 cancer cell lines, with IC₅₀ values ranging from 14 to 95 μM. For comparison, cisplatin exhibited IC₅₀ values between 0.33 and 22 μM under the same conditions
Langue(s) et précarité(s)
No full textInternational audienceThis chapter describes the theoretical framework that underpinned the case studies in this book. It begins by setting out the defining elements of our approach to the subject of “language” as a linguistic system, a social practice and a symbolic and identity-related issue. Secondly, we define what we mean by precariousness, and also by precariousness as a dynamic process. Finally, we set out our methodological framework, based on the analysis of complex dynamic systems.Ce chapitre rend compte du cadre théorique à l’origine de la rédaction des études de cas qui constituent cet ouvrage. Il pose dans un premier temps les éléments définitoires de ce que nous avons retenu pour traiter de l’objet « langue », pris comme un système linguistique, comme une pratique sociale et comme enjeu symbolique et identitaire. Dans un second temps, nous définissons ce que nous entendons par précarité mais aussi par précarisation, en tant que processus dynamique. Enfin, nous posons le cadre méthodologique construit autour d’une analyse des systèmes dynamiques complexes
Déstabiliser sans bouleverser : proposer une ingénierie combinant pédagogies actives et outils technopédagogiques pour engager les étudiant.e.s à l’université
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Phytomanagement strategy leads to plant-derived catalysts for the sustainable synthesis of oxidized Hantzsch esters
No full textInternational audienceThis study proposes a phytomanagement strategy to produce plant-derived eco-catalysts from Lolium perenne (ryegrass) and Trifolium incarnatum (clover), cultivated in contaminated or nutrient-rich soils from two French regions (Pompey and Bordeaux, respectively) and two Belgium sites (Duferco and Vieille Montagne, respectively), for the sustainable oxidation of Hantzsch esters and other substrates. Accumulating plants, cultivated in nutrient-rich or contaminated soils, provide catalysts enriched with transition metals like copper and zinc, supporting green chemistry principles by minimizing hazardous waste and fostering resource circularity. These catalysts were evaluated for the oxidation of Hantzsch esters to pyridines, pyridine-4(1H)-thione to pyridine-4-thiol, cyclohex-2-enone to substituted phenol, and dihydroquinoxaline to hydroxyquinoxaline. Results demonstrated substrate-dependent performance influenced by electronic effects, metal composition, and reaction parameters, with conversions reaching up to 95% for BIO-P2 and 89% for BIO-V catalysts, surpassing traditional oxidants such as KMnO4. Solvent and catalyst loading optimizations further enhanced reaction efficiency, with acetonitrile identified as an appropriate solvent. This dual-purpose strategy combines environmental remediation with the development of efficient, plant-derived catalysts, offering a scalable, eco-friendly alternative for industrial and pharmaceutical oxidative processes while aligning with Sustainable Development Goals
Work Transformations and Changes in Healthcare Professionals’Identity in the Erea of Artificial Intelligence – A Sociological Literature Review
No full textInternational audienceThe rise of artificial intelligence (AI) in the healthcare sector is driving profound transformations in the work of healthcare professionals, altering both theirs practices and their relationship to work and professional identity. In response to these changes, this presentation offers a sociological literature review aimed at identifying the main themes studied, emerging research areas, and the blind spots in current research.The literature analysis reveals three major well-documented themes: automation and the redefinition of tasks, which raise questions about the delegation of activities to algorithms; the evolution of the caregiver-patient relationship, with a reconfiguration of human interactions in the face of digital tools; and the challenges of professional responsibility and ethics, which raise concerns about decision-making and professional ethics in a human-machine collaboration context.At the same time, three major emerging themes are gradually gaining attention in recent studies; social inequalities in the face of AI and the differentiated access to technologies, raising the issue of a digital divide within healthcare institutions; organizational transformations and the redistribution of responsibilities, particularly between healthcare professionals and managers in the governance of AI systems.Finally, several blind spots in research can be identified, three of which we aim to explore through a new research initiative: the technological appropriation processes by healthcare professionals and the actual use of AI; the meaning of work in a technological context to explore values and the evolution of the relationship to work; and the collective identity of professionals, facing a redefinition of their roles.This literature review thus aims to contribute to a better understanding of the ongoing transformations and to open new research perspectives
Ferrocene‐Based Kickers for the Radical Polymerization of Vinyl Chloride Under Suspension Conditions: Improvement of the Process
No full textInternational audiencePolyvinyl chloride (PVC) is primarily manufactured via radical suspension polymerization of vinyl chloride monomer (VCM). Previously, dual‐component ferrocene (Fc)‐based kickers have been shown to enhance this process by facilitating the controlled decomposition of organic peroxides into radicals during the initiation step. However, these systems often introduce issues such as suspension destabilization, crusting, and reduced PVC thermal stability. This study evaluates alternative Fc‐based kicker systems to address these challenges. Among the tested combinations, Fc/sodium hydroxymethanesulfinate (SFS) kicker proved most effective, reducing polymerization time by 24% while maintaining suspension stability. Additionally, PVC produced with Fc/SFS exhibited better thermal stability compared to previous systems employing Fc/ascorbyl palmitate (PAA). Nevertheless, uncontrolled energy release at high conversion rates posed challenges for industrial scalability. To address these issues, phase transfer agents, such as cetyltrimethylammonium bromide (CTAB), were incorporated alongside Fc/SFS to improve reactant interactions. Injecting CTAB at 40% VCM conversion stabilized the suspension and accelerated polymerization without excessive energy release. This optimized system achieved significant time savings while preserving PVC quality, presenting a promising solution for industrial implementation
Water soluble lignin extract from ozonation of Miscanthus giganteus for bioactive starch packaging films
No full textInternational audienceThe development of bio-based packaging materials is a crucial step toward sustainability, with natural additives playing a key role in enhancing their functionality. Due to their brittle structure, starch-based packaging materials require natural plasticizers at optimal concentrations to improve their flexibility and performance. In this study, we hypothesized that a water-soluble lignin derivative, obtained by ozonation of Miscanthus giganteus and exhibiting bioactive properties, could function simultaneously as plasticizer and bioactive agent to obtain active starch-based packaging films. The effects of lignin on mechanical, antioxidant, antimicrobial, UV-blocking properties, and retrogradation of potato starch-based films were examined. Starch-lignin films were prepared with varying lignin concentrations (0 %, 5 %, 10 %, and 20 %) using casting method. Increasing lignin content from 0 % to 10 % reduced Young's modulus and significantly improved ductility, with elongation rising from 35 % to 166 %, while 20 % lignin inclusion reversed these effects. The phenolic structure of lignin increased the contact angle from 50 % to 110 % for lignin contents of 0 %-10 %, without altering water vapor permeability. Xray diffraction analysis revealed a reduction in the crystallinity of lignin-containing films. All starch-lignin films exhibited UV-blocking properties. Antioxidant capacity, measured by the β-carotene assay, increased significantly from 0 % to 93 % with lignin content from 0 % to 20 %. Moreover, all the films containing lignin demonstrated bactericidal activity, reducing the viability of Escherichia coli and Staphylococcus aureus by 99.9 %. Lignin delayed film retrogradation during storage by reducing crystallinity compared to starch-glycerol films. These starch-lignin biofilms show significant potential as sustainable additives for active food packaging applications
Aux confins du silence : langages et métamorphoses du silence dans le monde hispanophone du Moyen Âge à nos jours
No full textEste número propone estudiar los lenguajes y metamorfosis del silencio en el mundo hispánico desde la Edad Media hasta nuestros días. Se parte de la constatación que el verbo «silenciar» en español no tiene traducción literal en francés porque cobra dos sentidos rotundamente opuestos, arrojando así luz en una contradicción inherente al estudio del silencio: se trata de la acción de un sujeto que decide callar algo, pero es también la sumisión de un sujeto por otro, es decir, la coerción sobre alguien obligado a permanecer callado. Con este número, deseamos ir más allá de la identificación de las formas, expresiones, relaciones al poder y rupturas del silencio. El objetivo es explorar la índole cambiante del silencio, la constante metamorfosis que hace de él un objeto en transformación. Se trata de estudiar hasta qué punto el silencio puede encontrarse en los confines –en el sentido de las zonas extremas atrapadas entre varios juegos de influencias–, por ejemplo, entre las diferentes disciplinas o entre las artes y los géneros. Es interesante además examinar cómo el silencio se desplaza más allá de las fronteras de la palabra y de la mera acción de hablar. Interrogar los lenguajes y las metamorfosis del silencio (subrayamos el plural), es a la vez identificar nuevas formas que permitan comprender el acto de no hablar mediante características que forman parte de su estructura expresiva y que son tan significativas como la propia palabra. Significa también identificar los espacios y las huellas del silencio: ¿dónde se sitúa? ¿El silencio se puede hallar únicamente en los vacíos de la ausencia, o puede encontrarse en el centro mismo de la diégesis, en descripciones o momentos de logorrea verbal? El silencio es esencialmente fluctuante, capaz de cambiar, de metamorfosearse para expresar, volver a expresar, aludir, romper fronteras y hacerse creativo.Ce numéro se propose d’étudier les langages et métamorphoses du silence dans le monde hispanique du Moyen-Âge à nos jours. Notre constat de départ est que le verbe « silenciar » en espagnol n’a pas de traduction littérale en français car il revêt deux sens diamétralement opposés, mettant ainsi en lumière une contradiction inhérente à l’étude du silence : c’est l’action d’un sujet qui choisit de taire quelque chose, mais c’est aussi la soumission d’un sujet par autrui, autrement dit, l’exercice d’une contrainte sur autrui alors forcé de rester coi. Par ce numéro, nous souhaitons aller au-delà de l’identification des formes, des expressions, des rapports au pouvoir et des ruptures du silence. La réflexion proposée veut interroger la forme en mouvement du silence, sa métamorphose constante qui en fait un objet en mutation. Il s’agit d’étudier dans quelle mesure le silence peut se retrouver dans les confins – au sens de zones des extrémités prises entre plusieurs jeux d’influences – par exemple entre les différentes disciplines, entre les arts et entre les genres, ou comment il se place au-delà des frontières de la parole et du simple dire. Interroger les langages et les métamorphoses du silence (nous insistons sur le pluriel), c’est à la fois identifier de nouvelles formes permettant de cerner l’acte de la non-parole par des traces qui font partie intégrante de sa structure d’expression et qui sont tout aussi signifiantes que le dire lui-même. Mais c’est tout autant identifier les lieux ou traces du silence : à quel niveau se situe le silence ? Le silence ne se retrouve-t-il que dans les béances de l’absence ou peut-il se retrouver au coeur même de la diégèse dans des descriptions ou des passages de logorrhée verbale ? Le silence est par essence fluctuant, capable de se mouvoir, de se métamorphoser pour exprimer, réexprimer, faire allusion, briser les frontières et devenir création
Identifying linear Ultra-Short Peptides in Agrifood: Challenges and Critical Insights.
No full textInternational audienceThis is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain