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Tectonic complexity of the Incapuquio Fault System, Peruvian Andes: Paleoseismic evidence for cascading Mw7 earthquakes along the Western Andean Front
No full textThis article is part of a Special issue entitled: ‘Paul Tapponnier’ published in TectonophysicsInternational audienceUnderstanding millennial-scale crustal fault activity through paleoseismological investigations is essential for seismic hazard assessment in active mountain belts. While megathrust seismicity in the Peruvian subduction zone is well-monitored, crustal fault activity along the densely populated Western Andes remains largely overlooked. In southern Peru, the Incapuquio Fault System (IFS) is a prominent active structure capable of generating recurrent Mw >7 earthquakes. This study presents paleoseismic evidence from three newly excavated trenches and integrates them with three previously published sites – six trenches in total - along four fault strands of the IFS, revealing at least five surface-rupturing earthquakes during the Holocene. The overlap in time of the most recent event, the Chiribaya event (∼500 BP), identified in all trenches, suggests two possible scenarios: (1) a single large rupture propagating along the Western Toquepala Fault (WTF), Eastern Toquepala Fault (ETF), and Copapuquio Fault (CF), implying a Mw 7.5 earthquake, or (2) a cluster of closely spaced events, likely within a few centuries. Additionally, two earlier surface-rupturing earthquakes were identified: the Miculla event (∼2300 BP), recorded in the Western Toquepala Fault, Copapuquio Fault, and Sama-Calientes Fault (SCF), and the Toquepala event (∼11,600 BP), which was identified in the Copapuquio Fault (CF). These events are temporally coincident with Plinian eruptions of the Misti volcano and large-scale landslides in the Andean forearc, raising the possibility of interactions among crustal faulting, volcanism, and stress redistribution associated with the megathrust seismic cycle. The IFS is a key seismic hazard driver in southern Peru, underscoring the need to expand assessments beyond megathrust activity
Biomarqueurs du cancer du rein chez des modèles murins
No full textInternational audienceKidney cancer (RCC) has been rising steadily for over 30 years, especially in Western countries. Kidney cancer is mostly asymptomatic in its early stages. There is a significant need for innovative diagnostic and prognostic tools, including biomarkers and imaging techniques, to screen for and diagnose RCC. This review aims to provide a list of the key molecular biomarkers involved in tumor promotion and proliferation, as well as the main histopathological and imaging measures used to assess renal tumorigenesis in small animals.A biomarker is a substance in blood, urine or tissue that indicates a measure of physiological or pathological state, which may or may not be in response to an environmental agent, whether chemical, physical or biological.L'incidence du cancer du rein est en constante augmentation depuis plus de 30 ans, notamment dans les pays occidentaux. Ce cancer est le plus souvent asymptomatique à ses débuts. Il existe un besoin important d'outils diagnostiques et pronostiques innovants, tels que des biomarqueurs et des techniques d'imagerie, pour le dépistage et le diagnostic du carcinome à cellules rénales (RCC).Cette revue vise à présenter une liste des principaux biomarqueurs moléculaires impliqués dans la promotion et la prolifération tumorales, ainsi que les principales mesures histopathologiques et d'imagerie utilisées pour évaluer la tumorigenèse rénale chez les petits animaux.Un biomarqueur est une substance présente dans le sang, l'urine ou les tissus qui indique un état physiologique ou pathologique, pouvant être ou non une réponse à un agent environnemental, qu'il soit chimique, physique ou biologique
Development of Evidence-based Guidelines on Assessment and Management of Internal Contamination with Transuranic Actinides
No full textInternational audienceObjectives: To describe the process of the development of evidence-based guidelines on the assessment and clinical management of internal contamination with transuranic actinides (specifically plutonium, americium, and curium) in incidents where workers, emergency responders, and the public might uptake these radionuclides internally through inhalation, ingestion, or wound contamination.Methods: The World Health Organization (WHO) set up a guidelines development group (GDG) that follows the protocol required for producing evidence-based recommendations as described elsewhere. The GRADE® approach was applied throughout the process, including developing research questions formulation, prioritization and rating the importance for the outcomes, assessing the certainty of the evidence, considering contextual factors, and making recommendations.Results: Through 3 working group meetings held 2023-2024, the GDG defined and rated patient-important health outcomes, and evidence gathered through systematic reviews and its certainty rating, working towards formulating the recommendations using an evidence-torecommendation (EtR) framework.Conclusions: The WHO protocol for developing health care management guidelines uses a transparent and robust evidence-based GRADE® approach. Once published, these guidelines will provide the first evidence-based recommendations for assessment and clinical management of internal contamination with transuranic actinides
Etude de l’alimentation totale française 3 (EAT3) - Rapport méthode
No full textCitation suggérée : Anses. (2025). Etude de l’alimentation totale française 3 (EAT3) - Rapport méthode. (saisine2019-SA-0010). Maisons-Alfort : Anses, 90 p
Avis de l'Anses relatif à la caractérisation et évaluation des impacts sur la santé de la consommation d’aliments dits ultratransformés
No full textAnses. (2024). Avis relatif à la caractérisation et à l'évaluation des impacts sur la santé de la consommation d’aliments dits ultratransformés. (saisine 2022-SA-0155). Maisons-Alfort : Anses, 104 p.L’Anses a été saisie le 27 août 2022 par la Direction générale de l’alimentation (DGAL) et par la Direction générale de la santé (DGS) pour caractériser et évaluer les impacts sur la santé de la consommation d'aliments dits ultratransformés.CONTEXTE ET OBJET DE LA SAISINE : Les résultats de l’étude Inca 3 (2014-2015) de l’Anses, publiée en 2017, ont documenté une augmentation de la consommation de produits transformés par les Français, en particulier ,chez les jeunes, par rapport à ce qui était observé dans l’étude Inca 2 (2006-2007). Cela contribue à « créer une distance entre les individus et leur alimentation, notamment en termes de connaissance de la composition des aliments » (Anses 2017).L’effet des aliments dits ultratransformés sur la santé est une thématique de recherche émergente, qui a conduit certaines agences sanitaires à s’emparer du sujet (AESAN 2020; FAO/OMS 2019; NNR 2023; SACN 2023). Un nombre croissant de publications scientifiques a en effet rapporté une association entre la consommation de produits dits ultratransformés et le risque de maladies chroniques.Si la préoccupation est aujourd’hui internationale et partagée tant au niveau scientifique qu’au niveau sociétal, il n’existe pas à ce jour de définition consensuelle des aliments transformés.La classification Nova, qui est la classification la plus utilisée par la recherche en épidémiologie, différencie les aliments en quatre classes en fonction notamment de leur degré de transformation et la classe Nova 4 correspond aux aliments considérés comme les plus transformés. En France, bien qu’il n’existe pas de définition réglementaire pour les aliments qualifiés d’ultratransformés, plusieurs recommandations officielles y font référence. Ainsi, les objectifs du Haut Conseil de la santé publique pour le Programme national nutrition santé (PNNS) sont « d’interrompre la croissance de la consommation des produits ultratransformés » et Santé publique France recommande « de limiter les boissons sucrées, les aliments gras, sucrés, salés et ultratransformés ». Le Programme national de l’alimentation et de la nutrition (PNAN) prévoit la caractérisation des aliments ultratransformés, l’étude de l’impact pour la santé de leur consommation et la priorisation des actions à mener. De plus, de nombreuses propositions, issues de rapports parlementaires, de la Convention citoyenne pour le climat ou d’initiatives citoyennes, portent sur les aliments ultratransformés, en lien avec l’étiquetage, la taxation, l’interdiction de la publicité ou la limitation en restauration collective.En réponse à la demande de la DGAL et de la DGS, l’Anses a mené une expertise sous les cinq angles suivants, procédant à :1 – la caractérisation des produits dits ultratransformés par une identification des procédés de transformation susceptibles d’induire sur la composition des aliments des modifications présentant un danger pour la santé ;2 – le recensement des classements existants des aliments selon leur degré de transformation et évaluation de leur pertinence au regard des caractéristiques identifiées précédemment ; 3 – l’étude des relations épidémiologiques entre la consommation d’aliments dits ultratransformés et les risques de maladies chroniques non transmissibles (MCNT) ;4 – la détermination, le cas échéant, en fonction des risques identifiés, à l’issue de l’analyse des études épidémiologiques, des facteurs responsables de la nocivité des aliments dits ultratransformés en vue d’identifier des leviers permettant de limiter les risques associés à leur consommation ;5 – l’identification des travaux scientifiques devant être conduits pour mieux caractériser les impacts sanitaires des aliments dits ultratransformés
Dust collection after the high fluence campaign of the WEST tokamak
No full textPart of special issue - Proceedings of the 26th International Conference on Plasma Surface Interactions in Controlled Fusion Devices (PSI-26)International audienceFor Phase 2 of WEST, the lower divertor was entirely equipped with actively cooled ITER grade plasma-facing units made of chains of tungsten beveled monoblocks. In this configuration, dust particles were collected in 2023, after the first plasma campaign mainly dedicated to repetitive long pulses in the conditions of attached plasmas to the divertor. Due to a high particle fluence and a significant tungsten erosion, large quantities of dust were produced. In addition to those produced during off-normal events and the flaking of deposits which are typical of tokamak wall erosion, dust particles due to the flaking of pure tungsten thin layers deposited on the shadowed areas of beveled monoblocks were found. As specific characteristic, these thin layers may not adhere to the divertor and consequently, may be peeled off and mobilized during plasma operation.This article is part of a special issue entitled: 'PSI-26' published in Nuclear Materials and Energy
Evaluation of the uncertainty in calculating nanodosimetric quantities due to the use of different interaction cross sections in Monte Carlo track structure codes
No full textInternational audienceThis study evaluates the uncertainty in nanodosimetric calculations caused by variations in interaction cross sections within Monte Carlo Track Structure (MCTS) simulation codes. Nanodosimetry relies on accurately simulating particle interactions at the molecular scale. Different MCTS codes employ distinct physical models and datasets for electron interactions in liquid water, a surrogate for biological tissues. The paper focuses on the Ionization Cluster Size Distribution (ICSD) generated by electrons of varying energies in nanometric volumes. Seven MCTS codes were tested using their native cross sections and a common dataset derived from averaging data used in the participating codes. The results reveal significant discrepancies among the codes in ICSDs and derived biologically relevant nanodosimetric quantities such as mean ionization numbers (M1) and probabilities of obtaining two or more ionizations (F2). The largest variations were observed for low-energy electrons, where the contribution from interaction cross sections dominates the overall uncertainties. For instance, M1 values for ICSDs of electron of 20 eV can differ by around 45 % (RSD) and 34 % (RSD) was found for F2 values of ICSDs of electrons of 50 eV. Using common cross sections substantially reduced the discrepancies, suggesting that cross section datasets are the primary source of variability. Finally, estimates of deoxyribonucleic acid (DNA) damage using the PARTRAC code highlight tht cross section variations have a non-negligible impact simulated biological outcomes, particularly for double-strand breaks (DSBs) Indeed, despite the fact that many other parameters in the simulation that can greatly differ from one code to another, the different interaction cross-sections studied in this work can lead to differences in the number of DSBs calculated with the PARTRAC code of up to 15%
Characterization and Modeling of Gravity-Driven Flashing of Superheated Water in a Pool Heated from Below
No full textInternational audienceGravity-driven flashing of superheated water, the topic of this paper, is a phase change phenomenonthat is tightly linked with some of the safety issues of a spent-fuel-pool loss-of-cooling accident. As detailed in thisarticle, the phenomenon has been empirically studied and characterized within the Aquarius laboratory-scaleexperimental device. Primarily, the performed tests unveil the occurrence conditions of the gravity-driven flashingphenomenon in a pool heated from below and its coupling with the degassing of dissolved gases that may takeplace within the liquid. Next, a set of dimensionless correlations describing the studied heat and mass transfers isderived from the data and presented for both the single-phase and the two-phase regimes of any conducted test.Then, a lumped-parameter model, relying on those correlations and describing the studied physics, is introduced.The model resolves the coupled mass and energy balance equations of the heated liquid pool. Last, this model isused to simulate a selected reference test. The performed simulations are successfully compared with the availableempirical data, with moderate discrepancies, thereby verifying the adequateness of the proposed model
Modeling and dosimetric characterization of a 3D printed pregnant woman phantom for fetal dosimetry in radiotherapy
No full textInternational audienceA phantom-based estimation of the fetal dose for pregnant women undergoing radiotherapy and its optimization are recommended by the French society for radiation oncology. The objective of this study was to model and print 3D bellies representing various stages of pregnancy, that could be added to a female ATOM® phantom, enabling fetal dose assessment through measurements for optimization studies. The bellies were designed based on fundal height values from gynecological references and printed using a Stratasys 3D Printer and VeroWhite resin. Its chemical composition was determined using a CHONS analyzer: 65.51% carbon (C), 7.95% hydrogen(H), 23.3% oxygen (O), and 2.89% nitrogen (N). Its physical density was assessed using the helium pycnometry method: 1.190 +/-0.001. The linear attenuation coefficients for VeroWhite resin were evaluated using two methods: by calculations based on the linear attenuation coefficients of each chemical element and by experimental attenuation measurements using a 6MV beam. Consistent results were obtained with both methods; the VeroWhite resin is approximately 15% higher attenuation than water according to the calculation method and approximately 12% higher attenuation than RW3 water equivalent plates with the experimental method. These results were considered as acceptable for comparative parametric studies of fetal dose