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Structural, morphological, and cytotoxicity evaluation of surfactant-modified niobium oxides
No full textInternational audienceAbstract The employment of metal nanoparticles for biomedical applications is gaining visibility as a result of their excellent properties. Niobium oxide (Nb 2 O 5 ) possesses interesting physicochemical properties that can be modified for its use in prosthetic coatings. However, there are only a limited number of studies in the literature concerning its characterization as a pure powder, its surface modification and their cytotoxicity. Therefore, the purpose of this study was to evaluate nine different Nb 2 O 5 samples synthesized using the microwave technique, each with a different surfactant. x-ray diffraction results indicated that all samples were amorphous, and the addition of surfactants did not seem to cause any alterations, as indicated by Raman and FTIR. Scanning electron microscopy (SEM) images revealed that the particles tended to form aggregates; modification of parameters such as surface area and acid sites was also observed, with pure Nb 2 O 5 having the highest area (230.4 m 2 g −1 ) and NbSDS5 having the highest total acidity (3141 µmol g −1 ). We assessed the cytotoxicity in sheep’s erythrocytes and the Zebrafish Liver (ZF-L) cell line. Pure Nb 2 O 5 exhibited high cytotoxicity at 10 mg ml −1 in red blood cells with an erythrocyte survival rate of 15%. The MTT assay that revealed that NbCA1 showed only 27.1% cell viability, while NbSDS1 was able to increase cell proliferation (101.1%) even at a lower pH. Compounds were also able to interfere with the intrinsic coagulation pathway, with several samples exceeding the clotting time (>120 s). Nb ions leaching to the medium does not seem to directly affect cytotoxicity. Pearson’s correlation does not indicate a direct relationship between surface area, acid sites, and cytotoxicity assays
« Écriture sociologique, écriture cinématographique. Normes et attendus partagés »
No full textInternational audienceThis communication questions the forms of writing in the social sciences from two projects carried out head-on last year: the financing file for a film entitled You will do it in memory of me (Region 2025 file) and the scientific file of request for delegation and HDR, whose heart is the production of the film. These two projects fall under different writing regimes - artistic and scientific - but answer each other in the same question: how can sociological research be expressed through a filmic language, and vice versa, how can cinema become a mode of investigation and knowledge?Cette communication interroge les formes d’écriture en sciences sociales à partir de deux projets menés de front cette dernière année : le dossier de financement d’un film intitulé Vous ferez cela en mémoire de moi (dossier Région 2025) et le dossier scientifique de demande de délégation et d’HDR, dont le coeur est la réalisation du film. Ces deux projets relèvent de régimes d’écriture différents – artistique et scientifique – mais se répondent dans une même interrogation : comment la recherche sociologique peut-elle s’exprimer à travers un langage filmique, et inversement, comment le cinéma peut-il devenir un mode d’enquête et de connaissance
Microbiote intestinal et cancer colorectal: futures implications cliniques
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New femoral evidence from the Afar reveal the early evolution of habitual squatting behaviors in the genus Theropithecus
No full textInternational audienceIntroduction: The femoral anatomy of fossil Theropithecus is poorly known, although it provides critical data for inferring squatting behaviors, a characteristic trait of extant Theropithecus gelada .Methods: Here, we describe and provide functional and taxonomic interpretations on two subcomplete femora from the Afar Depression using a combination of traditional morphometrics (bivariate and multivariate) and 2D geometric morphometric combined with multivariate analyses and hierarchical clustering.Results: The ca. 3.20 Ma A.L. 206–1 femur is identified as the oldest known and most complete femur of an adult Theropithecus cf. oswaldi darti and shows a morphology similar to that of extant T. gelada . It supports the hypothesis of an early emergence of squatting behaviors in Theropithecus , prior to the onset of dental adaptations related to the grazing diet of the genus. The ca. 2.60 Ma A.L. 94–5 femur is identified as the oldest and most complete femur known of an adult Theropithecus cf. oswaldi oswaldi . Its knee anatomy is distinct from that of T. o. darti but it nonetheless shares with T. gelada and other fossil Theropithecus functional traits related to squatting behaviors. Unexpected convergences with arboreal cercopithecids are observed in Theropithecus brumpti , indicating diversity in the femoral functional anatomy of Theropithecus .Discussion: Overall, our study highlights the future need to link femoral anatomical diversity with postural and locomotor behaviors by combining paleontological data with neontological data including biomechanical data on the squatting and climbing of large extant papionins
La réforme des fonds européens en région : quels enjeux ?
No full textInternational audienceCommunication lors du colloque sur L'avenir des fonds européens en région : évolution ou révolution ?, université de Poitiers, 1er oct. 202
Migration : cartographier les absents
No full textNational audienceDans son projet de doctorat, Léna Haziza explore le vécu de la migration et du lien àdistance à travers le point de vue des femmes algériennes qui restent. Comment représenter l’absence dans le contexte de la migration, du lien à distance et des femmes qui restent ? Tel est le fil directeur de notre démarche. Elle s’inscrit dans le cadre du projet de Léna Haziza (sociologue et doctorante au Mesopolhis et à Migrinter) qui s’intéresse au vécu de la migration du point de vue des personnes qui restent, c’est-à-dire, les femmes qui ne migrent pas mais dont un proche a dû partir à l’étranger. En appui à sa recherche, Anne Tricot ( ingénieure CNRS au Mesopolhis spécialiste méthodes qualitatives et créatives ) l'a accompagnée pour réaliser son protocole d'enquête et ses entretiens de terrain dans une perspective multimodale associant entretiens, cartes mentales et photo-élicitation. La présentation s'est faite sous forme de dialogue où la chercheuse et l’ingénieure montrent au fur et à mesure les adaptations nécessaires au contexte de la recherche : à l’objet de la recherche mais aussi au contexte du pays dans laquelle elle se déroule. Un contexte politique sensible, qui nécessite la prise de précautions pour que la recherche puisse se dérouler sans que la chercheure ne prenne de risques inconsidérés
L’évolution des pratiques de multitasking des étudiants à l’université
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