1,141 research outputs found
D'ailleurs elle est d'ici. A propos de "La mort du dieu serpent" de D. Froidevaux
No full textA l'occasion des projections de "La mort du Dieu serpent" film de Damien Froidevaux au Festival du Réel (les 20 et 28 mars prochains) et dans de nombreux autres festivals dans les prochains mois, le texte écrit par Alexandra Galitzine-Loumpet, à la suite de ceux de Marie Darrieussecq et de Laurent Mauvignier (télécharger le dossier de presse ici). D'ailleurs, elle est d'ici. Le film commence par le récit haché d’une jeune femme - un débit de mitraillette, des gestes désorientés. Une ..
D'ailleurs elle est d'ici. A propos de "La mort du dieu serpent" de D. Froidevaux
No full textA l'occasion des projections de "La mort du Dieu serpent" film de Damien Froidevaux au Festival du Réel (les 20 et 28 mars prochains) et dans de nombreux autres festivals dans les prochains mois, le texte écrit par Alexandra Galitzine-Loumpet, à la suite de ceux de Marie Darrieussecq et de Laurent Mauvignier (télécharger le dossier de presse ici). D'ailleurs, elle est d'ici. Le film commence par le récit haché d’une jeune femme - un débit de mitraillette, des gestes désorientés. Une ..
Novel DGT Configurations for the Assessment of Bioavailable Plutonium, Americium, and Uranium in Marine and Freshwater Environments
No full textPlutonium, americium, and uranium contribute to the radioactive contamination of the environment and are risk factors for elevated radiation exposure via ingestion through food or water. Due to the significant environmental inventory of these radioelements, a sampling method to accurately monitor their bioavailable concentrations in natural waters is necessary, especially since physicochemical factors can cause significant temporal fluctuations in their waterborne concentrations. To this end, we engineered novel diffusive gradients in thin-film (DGT) configurations using resin gels, which are selective for UO22+, Pu(IV + V), and Am(III) among an excess of extraneous cations. In this work, we also report an improved synthesis of our in-house ion-imprinted polymer resin, which we used to manufacture a resin gel to capture Am(III). The effective diffusion coefficients of Pu, Am, and U in agarose cross-linked polyacrylamide were determined in freshwater and seawater simulants and in natural seawater, to calibrate these configurations for environmental deployments.</p
Time-integrated bioavailability proxy for actinides in a contaminated estuary
No full textActinides accumulate within aquatic biota in concentrations several orders of magnitude higher than in the seawater [the concentration factor (CF)], presenting an elevated radiological and biotoxicological risk to human consumers. CFs currently vary widely for the same radionuclide and species, which limits the accuracy of the modeled radiation dose to the public through seafood consumption. We propose that CFs will show less dispersion if calculated using a time-integrated measure of the labile (bioavailable) fraction instead of a specific spot sample of bulk water. Herein, we assess recently developed configurations of the diffusive gradients in thin films (DGT) sampling technique to provide a more accurate predictor for the bioaccumulation of uranium, plutonium, and americium within the biota of the Sellafield-impacted Esk Estuary (UK). We complement DGT data with the cross-flow ultrafiltration of bulk seawater to assess the DGT-labile fraction versus the bulk concentration. Sequential elution of Fucus vesiculosis reveals preferential internalization and strong intracellular binding of less particle-reactive uranium. We find significant variations between CF values in biota calculated using a spot sample versus using DGT, which suggest an underestimation of the CF by spot sampling in some cases. We therefore recommend a revision of CF values using time-integrated bioavailability proxies
Have breasts been forgotten in feminist struggles?
No full textVersion française ICI.*all the citations have been translated by myself. Camille Froidevaux-Metterie has just published Seins : en quête d'une libération (Anamosa, 2020). Her work follows in the wake of phenomenology as used by Simone de Beauvoir and Iris Marion Young. To read our interview, click HERE. At the beginning of this book on breasts, Camille Froidevaux-Metterie tells us a personal anecdote, which undoubtedly echoes in many of us. One day, the author goes to a lingerie store to buy..
Ordinary and indicator kriging of monthly mean nitrogen dioxide concentration in the United Kingdom
No full textThe UARS microwave limb sounder version 5 data set: Theory, characterization, and validation
No full textThis paper describes the latest and (for most products) definitive data set from the Microwave Limb Sounder (MLS) on the Upper Atmosphere Research Satellite (UARS). MLS data have formed the basis of numerous studies, and the version 5 data, produced using more advanced algorithms than earlier versions, represent a significant improvement in quality and scientific applicability for most of the MLS data products. The version 5 data include midstratospheric to lower mesospheric temperature and geopotential height (the latter is a new product from MLS), water vapor from the upper troposphere to the mesosphere, stratospheric and mesospheric ozone, and stratospheric nitric acid, chlorine monoxide, and methyl cyanide (also a new product). The vertical retrieval grid over the stratosphere and lower mesosphere has been doubled, to six surfaces per decade change in pressure (∼2.5 km), compared to three surfaces per decade in previous versions. The accuracy and precision of lower stratospheric ozone, chlorine monoxide, and nitric acid have been improved. For each product, a description of relevant changes to the algorithms is given, along with an update on its validation, a description of the accuracy, precision, and vertical resolution of the data, and information on what quality control methods to apply when using the data
Seismic imaging, plate velocities and geoid: the direct and inverse problem
No full textcited By 4International audienceThe dynamics of the Earth's mantle, which has a clear signature at the surface in the form of plate motion, can only be investigated indirectly. We discuss a physical model based on a viscous mantle with rigid surface plates. The mantle circulation excited by seismically defined density heterogeneities is computed. It is highly 3-D, and exhibits two major upwellings located beneath the two observed geoid highs. The same physical model is then used to solve the inverse problem, where plate velocities, geoid and plate surface topography are used as constraints for predicting the best mantle viscosity profile. -from Author
Integration of Detectors Into a Large Experiment: Examples From ATLAS and CMS
No full textIntegration of Detectors Into a Large Experiment: Examples From ATLAS andCMS, part of 'Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms: Numerical Data and Functional Relationships in Science and Technology, Volume 21B2: Detectors for Particles and Radiation. Part 2: Systems and Applications'. This document is part of Part 2 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Chapter '5 Integration of Detectors Into a Large Experiment: Examples From ATLAS and CMS' with the content: 5 Integration of Detectors Into a Large Experiment: Examples From ATLAS and CMS 5.1 Introduction 5.1.1 The context 5.1.2 The main initial physics goals of ATLAS and CMS at the LHC 5.1.3 A snapshot of the current status of the ATLAS and CMS experiments 5.2 Overall detector concept and magnet systems 5.2.1 Overall detector concept 5.2.2 Magnet systems 5.2.2.1 Radiation levels 5.2.3 Lessons learned from the construction experience 5.2.3.1 Time-scales, project phases and schedule delays 5.2.3.2 Physicists and engineers: how to strike the right balance? 5.2.3.3 International and distributed: a strength or a weakness? 5.2.3.4 A well integrated and strong Technical Co-ordination team 5.3 Inner tracking system 5.3.1 Introduction 5.3.2 Construction experience 5.3.2.1 General aspects 5.3.2.2 Silicon-strip and straw tube trackers 5.3.2.3 Pixel detectors 5.4 Calorimeter system 5.4.1 General considerations 5.4.1.1 Performance requirements 5.4.1.2 General features of electromagnetic calorimetry 5.4.1.3 General features of hadronic calorimetry 5.4.2 Construction experience and measured performance in test beam 5.5 Muon spectrometer system 5.5.1 General considerations 5.5.1.1 Muon chamber types 5.5.1.2 Muon chamber alignment and B-field reconstruction 5.5.1.3 Alignment 5.5.2 Construction experience and measured performance in laboratory and test beam 5.6 Trigger and data acquisition system 5.6.1 General considerations 5.6.2 L1 trigger system 5.6.2.1 Muon trigger 5.6.2.2 Calorimeter trigger 5.6.3 High-level trigger and data acquisition systems 5.6.3.1 Data acquisition 5.6.3.2 High-level trigger 5.7 Computing and Software 5.7.1 Computing Model 5.7.1.1 Event Data Model 5.7.1.2 Data Flow and Processing 5.7.2 Software 5.7.3 Analysis Model 5.8 Expected performance of installed detectors 5.8.1 Tracker performance 5.8.2 Calorimeter performance 5.8.2.1 Electromagnetic calorimetry 5.8.2.2 Hadronic calorimetry 5.8.3 Muon performance 5.8.4 Trigger performance 5.9 Conclusio
Bioavailable actinide fluxes to the Irish Sea from Sellafield-labelled sediments
No full textNuclear discharges to the oceans have given rise to significant accumulations of radionuclides in sediments which can later remobilise back into the water column. A continuing supply of radionuclides to aquatic organisms and the human food chain can therefore exist, despite the absence of ongoing nuclear discharges. Radionuclide remobilisation from sediment is consequently a critical component of the modelled radiation dose to the public. However, radionuclide remobilisation fluxes from contaminated marine sediments have never been quantitatively determined in-situ to provide a valid assessment of the issue. Here, we combine recent advances in the Diffusive Gradients in Thin Films (DGT) sampling technique with ultrasensitive measurement by accelerator mass spectrometry (AMS) to calculate the remobilisation fluxes of plutonium, americium and uranium isotopes from the Esk Estuary sediments (UK), which have accumulated historic discharges from the Sellafield nuclear reprocessing facility. Isotopic evidence indicates the local biota are accumulating remobilised plutonium and demonstrates the DGT technique as a valid bioavailability proxy, which more accurately reflects the elemental fractionation of the actinides in the biota than traditional bulk water sampling. These results provide a fundamental evaluation of the re-incorporation of bioavailable actinides into the biosphere from sediment reservoirs. We therefore anticipate this work will provide a tool and point of reference to improve radiation dose modelling and contribute insight for other environmental projects, such as the near-surface and deep disposal of nuclear waste
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