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International audience; This paper presents this analysis of the low power, high power and transient power commissioning tests of the CABRI reactor that were performed from 2015 to 2017. The comparison between experimental results and calculational results is given and concludes to a good consistency. Those tests allowed defining the authorized domain of operation of CABRI, better mastering the boundary conditions of the CABRI RIA tests and validating the reference neutronic calculation scheme used for safety and design studies.

International audience; CABRI is an experimental pulse reactor operated by the CEA at the Cadarache research center. After its refurbishment, it is now able to provide experiments in prototypical PWR conditions (155 bar, 300DC). Before operating, commissioning tests were performed, including control rod worth measurements. These experi-ments are done thanks to the rod-drop technique, which gathers static and dynamic effects. This paper reminds the theoretical background of the rod drop analysis. Then it gives a rigorous definition for the MSM factors (i.e. spatial correction factors to take into account the modification of the detector efficiency). An uncertainty analysis is performed and results prove the validity of the proposed model. Finally, the conclusion focuses on some possible improvements, like a rigorous importance calculation using the stochastic code TRIPOLI-4 and the use of different nuclear data libraries.

International audience; CABRI is an experimental pulse reactor operated by CEA at the Cadarache research center and funded by the French Nuclear Safety and Radioprotection Institute (IRSN).For the purpose of the CABRI International Program (CIP), operated and managed by IRSN under an OECD/NEA framework it has been refurbished since 2003 to be able to provide experiments in prototypical PWR conditions (155 bar, 300 DC) in order to study the fuel behavior under Reactivity Initiated Accident (RIA) conditions.This paper first reminds the design and the goals of the dosimetry program that was built in support of the commissioning tests performed for the reactor restart and requalification. Then it focuses on the irradiation conditions for each dosimeter and presents the measurement results. Finally, an analysis of the dosimetry campaign including measurement-calculation comparisons is presented.

Estimation de l’adhésion aux repères de la pyramide méditerranéenne chez les adultes des régions Provence-Alpes-Côte-d’Azur et Languedoc-Roussillon (PACA-LR). Journées francophones de nutrition (JFN 2016)

International audience; SFR are a solution for the future of nuclear energy. The safety constraints brought by nowadays standards, especially about Sodium void reactivity effect, require core designs which are highly heterogeneous axially and rather flat. These features require an in depth analysis of spatial effects which involves appropriate methodologies. This paper presents a comparison of results obtained with first order perturbation, flux harmonics and coupled-core theories. This last one presents some advantages compared to the other ones for understanding the spatial effects of large SFR cores, and for propagating nuclear data uncertainties.

National audience

National audience; The IRSN ENVIRHOM-Health research program, using an experimental animal model mimicking chronic contamination of residents of contaminated territories (such as those around Chernobyl and Fukushima), showed that chronic ingestion of low-dose radionuclides results in extensive but low-amplitude biological damage, with the subtle ruptures of metabolic equilibrium that are characteristic of internal exposure. In vivo internal contamination of radionuclides can affect numerous important metabolic systems of the organism, including those of cholesterol, vitamin D, iron, steroid hormones, and xenobiotics, without producing any toxic effects or visible pathology. To complement and refine these findings, in collaboration with the broad-spectrum metabolic analysis platform of the University of Aix-Marseille (CRIBIOM), we conducted studies that combined a metabolomic approach to low-dose radiotoxicology for the first time. The results of these experimental studies, which focused on the biological effects on rats of chronic ingestion of cesium 137 and natural uranium over several months, showed modifications of the metabolome after this internal exposure. Individuals exposed to these low doses could be identified metabolomically, even though their conventional clinical markers were unaffected. Thus, a metabolomic approach using simple blood or urine analysis appears useful for defining the biological signature of internal contamination by a low radionuclide dose. Finally, the identification and the simultaneous quantification of many affected molecules defined a specific fingerprint of exposure and could help to identify exposure biomarkers, early biological effects, and toxicity leading to the eventual development of pathology. In conclusion, metabolomics is one of the modern analytical approaches with considerable potential in the area of low-dose toxicology. Copyright © 2015 JOHN LIBBEY EUROTEXT.; Un modèle expérimental animal, mimant la contamination chronique des populations vivant sur des territoires contaminés a été utilisé dans le cadre du programme de recherche ENVIRHOM-Santé de l’Institut de radioprotection et de sûreté nucléaire (IRSN). Il a révélé que l’ingestion chronique de radionucléides à faibles doses entraînait des atteintes biologiques multiples de faibles amplitudes caractérisées par des ruptures subtiles d’équilibres métaboliques consécutives à l’exposition interne. En effet, il a été montré qu’une contamination interne de radionucléides était capable d’affecter in vivo un certain nombre de métabolismes majeurs de l’organisme, tels que le métabolisme du cholestérol, de la vitamine D, du fer, des hormones stéroïdiennes et des xénobiotiques sans effet toxique ou apparition de pathologie. Pour compléter et affiner ces connaissances, des études associant pour la première fois une approche métabolomique à la radiotoxicologie des faibles doses ont été initiées en collaboration avec la plate-forme d’analyse métabolique à large spectre de l’université d’Aix-Marseille (CRIBIOM). Les résultats de ces études expérimentales, qui portent sur les effets biologiques d’une ingestion chronique de césium 137 ou d’uranium naturel chez le rat pendant plusieurs mois, ont permis de montrer que, suite à ces expositions internes, il était possible d’identifier des individus contaminés par de faibles doses de radionucléides (bien que leurs taux de marqueurs cliniques classiques n’étaient pas affectés) par une modification de leur métabolome. Aussi, une simple analyse sanguine ou urinaire par approche métabolomique semble pertinente pour définir la signature biologique d’une contamination interne à faible dose de radionucléide. Enfin, l’identification et la quantification simultanée de plusieurs acteurs moléculaires impactés ont permis de définir « l’empreinte métabolique » spécifique de l’exposition et pourraient permettre de révéler des biomarqueurs d’exposition, d’effets biologiques précoces, de toxicité voire d’éventuels développements pathologiques. En conclusion, la métabolomique fait partie des approches analytiques modernes dont le potentiel reste considérable dans le domaine des faibles doses.

International audience; With the evolution of technology and the development of many mobile applications, the concepts of support, monitoring, guiding and safety of persons are democratized, and affect more or less strong on people mobility. With the multitude of applications that emerged, presentations, features, purposes and usages are many. The possibility of setting scenario and connection between them is a complex and burdensome exercise. In this context, we have worked in terms of features and use, transcending the applications themselves.