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Respirer avec K. Méthodes et enjeux cartographiques
No full textNational audienceCe texte se propose de mener une discussion avec et autour d’une cartographie , celle de l’itinéraire de K., un homme, asthmatique et allergique. Nous - deux chercheurs et une architecte cartographe - avons expérimenté avec K. un itinéraire en marchant centré sur sa respiration et son expérience ordinaire de l’air, en nous donnant l’objectif suivant : produire une cartographie qui non seulement exprime l’expérience de l’itinéraire, mais aussi constitue un outil réflexif et critique des espaces publics contemporain
Proton beam monitoring through water scintillation in radiobiology experiments
No full textInternational audienceNon-invasive methods based on the detection of secondary particles generated in the irradiated medium are being investigated to monitor ion beams without disturbing the beam. This study investigates the use of water scintillation as a beam monitoring tool, taking into account the challenges posed by the radiobiology experiment constraints. An experimental setup has been designed to measure the depth deposited energy profile produced by protons of (67.5 ± 0.4) MeV entering a water tank, through the water scintillation detected with a photomultiplier. The beam current during the experiment was around 100 pA, and beam intensity fluctuations were monitored using a parallel plate ionization chamber and a Faraday cup. The experiment was repeated with a second ionization chamber as a reference detector placed inside the water tank, and simulated with the GATE Monte Carlo code. The position of the Bragg peak, measured with the water scintillation, shows significant agreement (deviation of 0.5 mm) with the positions obtained from the ionization chamber and the Monte Carlo simulation within a submillimeter uncertainty. The ionization quenching effect was also observed and corrected using the Birks and Chou models. A new value of the key parameter for these models (k · B = (8.0 ± 4.0) × 10−3 g/MeV.cm2) has been determined for water, which is in good agreement with the data available in the literature for organic scintillators. This study demonstrated the feasibility of using water scintillation measured with a collimated photomultiplier as a tool for monitoring the depth deposited energy profile in water. •Water scintillation is used to monitor proton beams in radiobiological experiment.•The Bragg peak is localized with submillimeter uncertainty.•The Chou model allows for correction of ionization quenching for water.•The Birks and Chou parameters were determined for water
Differences in VLE adoption: longitudinal and large-scale analysis of contextual effects on French teachers' TEL practices
No full textInternational audienceAgainst the widespread use of virtual learning environments (VLEs) in French schools, this research examines their adoption by primary and secondary school teachers by detecting digital maturity profiles based on activity traces. The aim is to analyze the diversity and intensity of the activities carried out in VLEs to identify these profiles and better understand the conditions of their emergence. Based on the statistical processing of VLE data from 144,900 teachers in three academies over 2 school years, we constructed three indicators (MatU, MatD, MatF) to qualify the use in terms of combination, diversity, and frequency of VLE services used. The results reveal five general profiles that differ according to the academic district, the level of education, or the period in which the VLE was deployed. This shows that digital maturity is strongly linked to contextual variables. These profiles suggest that some contexts favor the adoption of complex, collaborative uses, especially in schools that adopted VLE just after the health crisis. The study thus highlights the role of the institutional framework in structuring and sustaining the use of digital technologies in education
Les animaux dans le monde romain. Penser l’anthropocentrisme
No full textInternational audienceWhat is anthropocentrism? How does it differ from speciesism? When did our unbalanced relationship with animals begin? Why and how? This book answers these questions by going back to the roots of our culture, the Roman world, not forgetting our Greek heritage. It was then that the relationship with animals and their place within the city was theorised. Animals were also ‘animalised’, in the same way that women and barbarians were animalised. However, nothing was set in stone: some voices pleaded their cause, but were quickly silenced. Philosophers and theologians preferred to go in search of a hypothetical ‘proper of man’, while jurists enshrined his excellence in law. The book leaves no stone unturned and questions the logic behind certain practices (veterinary medicine, vivisection, zootechnics, etc.).Drawing on our history and the contributions of cognitive science and anthropology, the author proposes a redefinition of anthropocentrism and presents speciesism as a choice of civilisation to which we are heirs.Qu’est-ce que l’anthropocentrisme ? Qu’est-ce qui le différencie du spécisme ? Quand notre rapport aux animaux, si déséquilibré, s’est-il mis en place ? Pourquoi et selon quelles modalités ? C’est à ces questions que ce livre répond en revenant aux racines de notre culture, le monde romain, non sans tenir compte de l’héritage grec. C’est alors que l’on a théorisé la relation aux animaux et leur place au sein de la cité. Alors aussi les animaux ont été « animalisés », au même titre que l’on a animalisé les femmes et les barbares. Pour autant, rien n’était tracé : des voix ont plaidé leur cause, vite étouffées. Philosophes et théologiens ont préféré partir à la recherche d’un hypothétique « propre de l’homme », tandis que les juristes ont consacré son excellence dans le droit. Le livre n’écarte aucun écueil et interroge les logiques commandant certaines pratiques (médecine vétérinaire, vivisection, zootechnie…).Par le truchement de notre histoire et en se fondant sur l’apport des sciences cognitives et de l’anthropologie, l’auteur propose de redéfinir l’anthropocentrisme et présente le spécisme comme un choix de civilisation dont nous sommes les héritiers
The grammar of ‘unanalyzable’ sentences in early child language production: Production mismatches in the development of Recursion in English
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Recombinant Human IgG1 Enhances Complement-Mediated Bacteriolysis and Macrophage Phagocytosis of Pseudomonas aeruginosa via Targeting Cell Surface Polysaccharides
No full textInternational audienceThe development of innovative therapeutics against WHO priority pathogens is an urgent global need. Here, we demonstrate the functionalities of a human antibody, previously isolated by whole cell biopanning of the phage display scFv library. The yPgi3G4 IgG1 could mediate antibody-dependent phagocytosis of Pseudomonas aeruginosa by human matured THP-1 monocytes, of which colocalization with caveolin was clearly observed at 24 h. Next, the antibacterial activity against live P. aeruginosa was demonstrated by an agglutination assay and complement-mediated killing of the bacteria. Lipopolysaccharide (LPS) extraction and Western blot (WB) analysis suggested that LPS was the target of the yPgi3G4 IgG1 antibody. A cross-reactivity assay to available isolates in Thailand and France showed that the antibody could detect 6 P. aeruginosa serotypes including several multidrug-resistant clinical isolates. This study proved the potential of using this strategy to identify a biotherapeutic for a certain quotient of multidrug-resistant P. aeruginosa and other bacterial infections
Qu’est-ce qui remplit les salles de concerts ? La nostalgie, pardi !
No full texthttps://theconversation.com/quest-ce-qui-remplit-les-salles-de-concerts-la-nostalgie-pardi-272744Sur les scènes françaises, les tournées « best of » ou les « tribute bands » occupent le terrain, remplissent les salles et structurent un véritable marché de la « nostalgie live ». Portés par une demande de réconfort émotionnel et de communion mémorielle, ces spectacles du passé remixés au présent interrogent. Comment comprendre un tel engouement pour ces pastiches et jusqu’où cette économie de la copie peut-elle prospérer sans trop étouffer la création
Multi-solvent suppression ultrafast 2D COSY for high-throughput wine screening
No full textInternational audienceNuclear Magnetic Resonance (NMR) is a powerful analytical tool for wine analysis, to identify and quantify a metabolite composition. However, a limiting factor of 1D 1 H NMR spectroscopy is the overlap of signals in complex mixtures. While conventional 2D NMR methods disperse the signal over two dimensions, they are associated with long experiment times. In the case of wine, interesting metabolites are also often masked by the large water and ethanol peaks. To improve wine analysis by NMR, a method that uses the advantages of 2D NMR while suppressing solvent signals and being within the timeframe of 1D NMR is highly desirable. Interleaved ultrafast COSY (iuf-COSY) offers a possibility for fast acquisition of a 2D spectrum and has been demonstrated as a powerful tool in metabolomics studies, as a complement to 1D NMR methods. Here, the iuf-COSY experiment has been adapted to suppress water and ethanol signals by using a shaped pulse and a NOESY block. This approach efficiently suppresses solvent signals and gives a 2D COSY spectrum of wine in approximately 20 min. Important metabolites that originally were covered by solvent signals could be annotated, while minimal interleaving artefacts were observed. This is an efficient method to acquire a COSY spectrum of a wine sample, which can aid with the identification and discrimination of metabolites in future wine studies through additional cross peaks, while working within a high-throughput time scale. This might be particularly interesting in the field of wine metabolomics, quality control, authenticity and fraud
Faster 4D Flow MRI Scan with 3D Arbitrary-Scale Super-Resolution
No full textInternational audience4D Flow MRI enables comprehensive hemodynamic assessment but remains constrained by prolonged acquisition times (10-15 min) and limited spatial resolution, hindering clinical deployment. Conventional super-resolution (SR) methods aim to enhance the original spatial resolution without accounting for acquisition time. This study investigates arbitrary-scale super-resolution (ASSR) frameworks applied to reduced-time acquisitions to recover clinical-grade resolution. Two generalisable ASSR architectures - LIIF and LTE - originally designed for 2D natural imagery, are reformulated for 3D volumetric data and trained exclusively on in-vivo measurements. To suppress background noise reconstruction, a Weighted Mean Frequencies (WMF)-based loss function is introduced, emphasising regions of high pulsatility. Furthermore, a physics-based regularisation term enforcing mass conservation is incorporated, analogous to PINN. Quantitative evaluation demonstrates that both ASSR models markedly outperform linear interpolation and a CFD-pretrained SURFR-Net baseline. The LTE model exhibits superior in-scale fidelity, whereas LIIF demonstrates enhanced generalisation across unseen scaling factors
"Moi, Arcade Hoang, Interprète chinois du Roi-Soleil" (法国太阳王的中文翻译 - 黄嘉略)
No full textISBN 2-7003-0474-8Danielle ElisseeffMoi, Arcade Hoang, Interprète chinois du Roi-Soleil"L'interprète chinois du Roi Soleil - Arcade Huang" est une autobiographie présentant un pionnier des premiers échanges culturels entre la Chine et la France. Le livre présente principalement la vie de Huang Jialiu, le premier Chinois à s'installer à Paris, et ses contributions à la diffusion de la culture chinoise et chinoise dans les premiers échanges entre la Chine et la France