240 research outputs found

    Detection of seismic site effects: Development of experimental methods and application to the city of Nice

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    Les effets de site reprĂ©sentent un enjeu important pour la prĂ©vention parasismique, puisqu’ils peuvent aggraver considĂ©rablement les dommages lors d’un sĂ©isme. La connaissance de la rĂ©ponse des sols aux sĂ©ismes permet d’adapter la rĂ©glementation parasismique Ă  ces contraintes lors de l’élaboration de microzonages et de Plan de PrĂ©vention des risques. Les mĂ©thodes expĂ©rimentales de dĂ©termination des effets de site visent Ă  obtenir les paramĂštres de l’amplification sismique par la mesure de sĂ©ismes ou de bruit de fond sismique. Cet article prĂ©sente les principaux rĂ©sultats obtenus jusqu’en 2005 par l’ERA « Risque sismique » dans la mise au point de ces techniques et leur application comparĂ©e sur la ville de Nice. Cette ville a effectivement constituĂ© le principal chantier d’application grĂące Ă  de multiples campagnes d’enregistrements sismiques. De nombreux sĂ©ismes ont d’abord Ă©tĂ© analysĂ©s par la mĂ©thode des fonctions de transfert. La mĂ©thode « H/V bruit de fond » a Ă©tĂ© appliquĂ©e sur plus de 600 points et les rĂ©sultats interpolĂ©s spatialement. Un modĂšle gĂ©otechnique du sous-sol a ensuite permis de comparer les rĂ©sultats obtenus avec la gĂ©ologie et des simulations numĂ©riques de la propagation des ondes. La complĂ©mentaritĂ© des mĂ©thodes et leurs atouts respectifs sont mis en valeur sur ce territoire Ă  fort enjeu.Site effects represent a critical challenge in the field of earthquake prevention since these effects are capable of seriously exacerbating damage whenever an earthquake strikes. Knowledge of the soil response to seismic activity allows adapting earthquake protection regulations to better incorporate these constraints during the process of defining microzones and producing the Risk Prevention Plan. The experimental methods employed to determine site effects seek to obtain seismic amplification parameters by means of measuring earthquakes or seismic background noise. This article presents the main set of results derived until 2005 by the “Seismic risk” ERA research team during development of these techniques as well as their comparative application to Nice, a city that has constituted the main field application site thanks to its hosting of multiple seismic recording campaigns. For starters, many earthquakes have been analyzed according to the transfer function method. The “Horizontal/Vertical background noise” method was in particular applied to over 600 points, with results being spatially interpolated. A geotechnical model of the subsoil then served to compare the results output with both the geology and numerical simulations of wave propagation. The complementarity of methods and their respective advantages are highlighted in this seismically-active setting

    Ici, là ou ailleurs ?

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    Cet article interroge l’action politique territorialisĂ©e sous l’angle de la localisation d’un grand Ă©quipement touristique, l’Espace de restitution de la grotte Chauvet (ERGG) (Sud-ArdĂšche, France). Fac-similĂ© de la grotte ornĂ©e Chauvet-Pont d’Arc, celui-ci vise Ă  restituer au plus grand nombre le contenu de cette derniĂšre, maintenue fermĂ©e pour des raisons de conservation. Entre la dĂ©couverte de la grotte (1994) et la sĂ©lection du site d’implantation pour l’ERGC (2009), quinze annĂ©es se sont Ă©coulĂ©es. Plusieurs projets se sont succĂ©dĂ©, les sites d’implantation retenus Ă©voluant selon les critĂšres mobilisĂ©s, eux-mĂȘmes liĂ©s aux Ă©volutions du contexte territorial. L’ERGC permet ainsi, sur un pas de temps relativement long, d’observer dans quelle mesure la localisation d’un grand Ă©quipement touristique interagit avec le registre de “la qualitĂ© des lieux”. AprĂšs une nĂ©cessaire mise en contexte, l’analyse des critĂšres et des sites successivement envisagĂ©s contribue Ă  Ă©clairer les enjeux que les acteurs attribuent Ă  cet Ă©quipement.This article deals with the territorialized political action under the prism of a big tourist equipping location: the copy of the Chauvet Cave (South of ArdĂšche, France). This one aims to restore to the largest public the original Chauvet Cave maintained closed for preservation reason. Between the discovery of the cave (1994) and the choice of the location for the restoring equipping (2009), fifteen years passed by. Several projects followed one another and the different locations selected for the restoring place have changed, depending on stakeholder’s game. This big tourist equipping project allows observing, with a diachronic approach, how the location decision process is connected with the “qualitĂ© des lieux”. The presentation of the local territorial context will then been followed by the comparison between these several projects, in order to explain the stakes and values attributed by the stakeholders to this equipping

    Identification of differentially expressed genes in chickens differing in muscle glycogen content and meat quality

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    <p>Abstract</p> <p>Background</p> <p>The processing ability of poultry meat is highly related to its ultimate pH, the latter being mainly determined by the amount of glycogen in the muscle at death. The genetic determinism of glycogen and related meat quality traits has been established in the chicken but the molecular mechanisms involved in variations in these traits remain to be fully described. In this study, Chicken Genome Arrays (20 K) were used to compare muscle gene expression profiles of chickens from Fat (F) and Lean (L) lines that exhibited high and low muscle glycogen content, respectively, and of individuals exhibiting extremely high (G+) or low (G-) muscle glycogen content originating from the F<sub>2 </sub>cross between the Fat and Lean lines. Real-time RT-PCR was subsequently performed to validate the differential expression of genes either selected from the microarray analysis or whose function in regulating glycogen metabolism was well known.</p> <p>Results</p> <p>Among the genes found to be expressed in chicken P. major muscle, 197 and 254 transcripts appeared to be differentially expressed on microarrays for the F vs. L and the G+ vs. G- comparisons, respectively. Some involved particularly in lipid and carbohydrate metabolism were selected for further validation studies by real-time RT-PCR. We confirmed that, as in mammals, the down-regulation of CEBPB and RGS2 coincides with a decrease in peripheral adiposity in the chicken, but these genes are also suggested to affect muscle glycogen turnover through their role in the cAMP-dependent signalling pathway. Several other genes were suggested to have roles in the regulation of glycogen storage in chicken muscle. PDK4 may act as a glycogen sensor in muscle, UGDH may compete for glycogen synthesis by using UDP-glucose for glucoronidation, and PRKAB1, PRKAG2, and PHKD may impact on glycogen turnover in muscle, through AMP-activated signalling pathways.</p> <p>Conclusions</p> <p>This study is the first stage in the understanding of molecular mechanisms underlying variations in poultry meat quality. Large scale analyses are now required to validate the role of the genes identified and ultimately to find molecular markers that can be used for selection or to optimize rearing practices.</p

    SchizophrĂ©nie, approche spĂ©cialisĂ©e et continuitĂ© de soins. Le programme spĂ©cifique d’intervention Premier-Épisode de l’HĂŽtel-Dieu de LĂ©vis

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    La schizophrénie est une maladie complexe à caractÚre évolutif. Reposant sur un cadre conceptuel d'orientation cognitive, le programme spécifique d'intervention Premier épisode de l'HÎtel-Dieu de Lévis fournit une évaluation complÚte et standardisée au plan individuel et familial. Puis sont rendues disponibles différentes modalités de traitement, selon une approche individuelle (psycho-éducation, psychothérapie) et de groupe (intervention psychologique au plan cognitif ou Integrated Psychological Therapy, de Brenner). L'intervention psycho-éducative familiale est également offerte aux familles. Les structures et la démarche décrites s'harmonisent avec celles qui étaient en place avant la création du programme, ce qui offre une continuité de soins. Le cadre conceptuel sous-jacent et les modalités du fonctionnement du programme sont aussi présentés.Schizophrenia is a complex illness with an evolutive character. Based on a conceptual framework of cognitive orientation, the specific intervention program First Episode of HÎtel-Dieu in Lévis includes a complete and standardized assessment to an individualized and family plan. Different methods of treatment acording to an individualized approach (psyhco-education, psychotherapy) as well as group therapy (psychological intervention at the cognitive level or Brenner's Integrated psychological therapy) are then proposed. Psycho-education intervention for families is also offered. Structures and different steps described here, harmonize with those already in place before the program's creation thus offering a continuity in care. The underlying conceptual framework and the different methods of functioning of the program are also presented.La esquizofrenia es una enfermedad compleja da caracter evolu-tivo. El programa especifico de intervention Primer episodio de HÎtel-Dieu de Lévis que reposa en un marco conceptual de orientaciÎn cognoscitiva, ofrece una evaluaciÎn compléta y estandarizada a nivel individual y familiar. Ademùs se ofrecen diferentes modalidades de tratamiento, segûn un enfoque individual (psicoeducaciÎn, psicoterapia) y de grupo (intervenciÎn psicolÎgica a nivel cognoscitivo o Integrated psychological therapy, de Brenner). Igualmente se le ofrece a las fami-lias, la IntervenciÎn psioeducativa familiar. Las estructuras y los pasos a seguir que se describen se armonizan a las que ya existian antes de la creation del programa, Io que ofrece una continuidad de tratamiento. Son presentados, el marco conceptual subyacente y las modalidades del fucionamiento des programa

    Sesame Project - Deliverable D08-02 - WP02 H/V technique : experimental conditions - Final report on Measurement Guidelines

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    In the following we report the final results for WP02-Measurement Guidelines. This work was conducted under the framework of the SESAME Project (Site Effects Assessment Using Ambient Excitations, EC-RGD, Project No. EVG1-CT-2000-00026 SESAME), Task A (H/V technique), Work Package 02 (WP02 – Measurement Guidelines).European Commission – Research General Directorate Project No. EVG1-CT-2000-00026 SESAMEPublished4.1. Metodologie sismologiche per l'ingegneria sismicaope

    The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

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    The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer, studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory, a versatile observatory designed to address the Hot and Energetic Universe science theme, selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), it aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over an hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR, browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters. Finally we briefly discuss on the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, and touch on communication and outreach activities, the consortium organisation, and finally on the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. (abridged).Comment: 48 pages, 29 figures, Accepted for publication in Experimental Astronomy with minor editin

    The Athena X-ray Integral Field Unit: a consolidated design for the system requirement review of the preliminary definition phase

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    The Athena X-ray Integral Unit (X-IFU) is the high resolution X-ray spectrometer studied since 2015 for flying in the mid-30s on the Athena space X-ray Observatory. Athena is a versatile observatory designed to address the Hot and Energetic Universe science theme, as selected in November 2013 by the Survey Science Committee. Based on a large format array of Transition Edge Sensors (TES), X-IFU aims to provide spatially resolved X-ray spectroscopy, with a spectral resolution of 2.5 eV (up to 7 keV) over a hexagonal field of view of 5 arc minutes (equivalent diameter). The X-IFU entered its System Requirement Review (SRR) in June 2022, at about the same time when ESA called for an overall X-IFU redesign (including the X-IFU cryostat and the cooling chain), due to an unanticipated cost overrun of Athena. In this paper, after illustrating the breakthrough capabilities of the X-IFU, we describe the instrument as presented at its SRR (i.e. in the course of its preliminary definition phase, so-called B1), browsing through all the subsystems and associated requirements. We then show the instrument budgets, with a particular emphasis on the anticipated budgets of some of its key performance parameters, such as the instrument efficiency, spectral resolution, energy scale knowledge, count rate capability, non X-ray background and target of opportunity efficiency. Finally, we briefly discuss the ongoing key technology demonstration activities, the calibration and the activities foreseen in the X-IFU Instrument Science Center, touch on communication and outreach activities, the consortium organisation and the life cycle assessment of X-IFU aiming at minimising the environmental footprint, associated with the development of the instrument. Thanks to the studies conducted so far on X-IFU, it is expected that along the design-to-cost exercise requested by ESA, the X-IFU will maintain flagship capabilities in spatially resolved high resolution X-ray spectroscopy, enabling most of the original X-IFU related scientific objectives of the Athena mission to be retained. The X-IFU will be provided by an international consortium led by France, The Netherlands and Italy, with ESA member state contributions from Belgium, Czech Republic, Finland, Germany, Poland, Spain, Switzerland, with additional contributions from the United States and Japan.The French contribution to X-IFU is funded by CNES, CNRS and CEA. This work has been also supported by ASI (Italian Space Agency) through the Contract 2019-27-HH.0, and by the ESA (European Space Agency) Core Technology Program (CTP) Contract No. 4000114932/15/NL/BW and the AREMBES - ESA CTP No.4000116655/16/NL/BW. This publication is part of grant RTI2018-096686-B-C21 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. This publication is part of grant RTI2018-096686-B-C21 and PID2020-115325GB-C31 funded by MCIN/AEI/10.13039/501100011033

    COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

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    Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≀ 18 years: 69, 48, 23; 85%), older adults (≄ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P &lt; 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

    Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star

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    Search for eccentric black hole coalescences during the third observing run of LIGO and Virgo

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    Despite the growing number of confident binary black hole coalescences observed through gravitational waves so far, the astrophysical origin of these binaries remains uncertain. Orbital eccentricity is one of the clearest tracers of binary formation channels. Identifying binary eccentricity, however, remains challenging due to the limited availability of gravitational waveforms that include effects of eccentricity. Here, we present observational results for a waveform-independent search sensitive to eccentric black hole coalescences, covering the third observing run (O3) of the LIGO and Virgo detectors. We identified no new high-significance candidates beyond those that were already identified with searches focusing on quasi-circular binaries. We determine the sensitivity of our search to high-mass (total mass M&gt;70 M⊙) binaries covering eccentricities up to 0.3 at 15 Hz orbital frequency, and use this to compare model predictions to search results. Assuming all detections are indeed quasi-circular, for our fiducial population model, we place an upper limit for the merger rate density of high-mass binaries with eccentricities 0&lt;e≀0.3 at 0.33 Gpc−3 yr−1 at 90\% confidence level
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