32 research outputs found
Cold atoms in space: community workshop summary and proposed road-map
We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies.publishedVersio
Cold atoms in space: community workshop summary and proposed road-map
We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies
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Cold atoms in space: community workshop summary and proposed road-map
We summarise the discussions at a virtual Community Workshop on Cold Atoms in Space concerning the status of cold atom technologies, the prospective scientific and societal opportunities offered by their deployment in space, and the developments needed before cold atoms could be operated in space. The cold atom technologies discussed include atomic clocks, quantum gravimeters and accelerometers, and atom interferometers. Prospective applications include metrology, geodesy and measurement of terrestrial mass change due to, e.g., climate change, and fundamental science experiments such as tests of the equivalence principle, searches for dark matter, measurements of gravitational waves and tests of quantum mechanics. We review the current status of cold atom technologies and outline the requirements for their space qualification, including the development paths and the corresponding technical milestones, and identifying possible pathfinder missions to pave the way for missions to exploit the full potential of cold atoms in space. Finally, we present a first draft of a possible road-map for achieving these goals, that we propose for discussion by the interested cold atom, Earth Observation, fundamental physics and other prospective scientific user communities, together with the European Space Agency (ESA) and national space and research funding agencies
OLES Online Laboratory for Environmental Sciences
International audienceThe integrated cyber-infrastructure, OLES, provides an access to observation data and to tools and models built to enhance our understanding on the evolution of the Earth's water resources and climate. OLES aims at i) extracting the required data from database portals using OGC webservice (CSW, SOS), ii) building a specific process chain based on modules that use NetCDF format for exchanging data, iii) running the process in chosen computing facilities, OLES can connect outside on a private LAN and iv) visualizing the result of the process. Based on J2EE, the MMI of OLES is a web interface and interacts with EJB objects. OLES uses web services to communicate with a sequencer developed in C++
MobRISK: a model for assessing the exposure of road users to flash flood events
International audienceRecent flash flood impact studies highlight that road networks are often disrupted due to adverse weather and flash flood events. Road users are thus particularly exposed to road flooding during their daily mobility. Previous exposure studies, however, do not take into consideration population mobility. Recent advances in transportation research provide an appropriate framework for simulating individual travel-activity patterns using an activity-based approach. These activity-based mobility models enable the prediction of the sequence of activities performed by individuals and locating them with a high spatial-temporal resolution. This paper describes the development of the MobRISK microsimulation system: a model for assessing the exposure of road users to extreme hydrometeorological events. MobRISK aims at providing an accurate spatiotemporal exposure assessment by integrating travel-activity behaviors and mobility adaptation with respect to weather disruptions. The model is applied in a flash-flood-prone area in southern France to assess motorists' exposure to the September 2002 flash flood event. The results show that risk of flooding mainly occurs in principal road links with considerable traffic load. However , a lag time between the timing of the road submersion and persons crossing these roads contributes to reducing the potential vehicle-related fatal accidents. It is also found that sociodemographic variables have a significant effect on individual exposure. Thus, the proposed model demonstrates the benefits of considering spatiotemporal dynamics of population exposure to flash floods and presents an important improvement in exposure assessment methods. Such improved characterization of road user exposures can present valuable information for flood risk management services
Magnetic resonance imaging as a tool to predict reparability of longitudinal full-thickness meniscus lesions
Prediction of meniscus reparability is useful for surgeons to optimise surgical scheduling and to inform patients about postoperative management. This study was designed to determine the accuracy of MRI in predicting the reparability of longitudinal full-thickness meniscus lesions. We studied 100 MRIs of longitudinal full-thickness medial or lateral meniscus lesions located from the meniscosynovial junction to the axial part of the meniscus. The MRI criteria of reparability were a peripheral rim smaller than 4 mm and a lesion longer than 10 mm. At arthroscopy the menisci were considered as reparable when the lesion was located in redâred or redâwhite zones and when it was more than 1 cm in length. A heterogeneous or homogeneous aspect of the meniscus body was also considered. The length of the meniscus lesion averaged 17.6 mm and the thickness of the rim 3.4 mm. A heterogeneous signal of the axial fragment and of the rim was found in 11 cases and in 48 cases, respectively. In 90 cases, there was no difference between the MRI-predicted reparability and the arthroscopic findings. Global sensitivity of MRI to determine reparability of full-thickness meniscus lesions was 94%, increasing to 96% for the medial meniscus and dropping to 83% for the lateral meniscus. Global specificity was 81%, and was higher for the lateral meniscus (90%) than for the medial one (82%). Global positive predictive value was 0.94 and global negative predictive value was 0.82. A heterogeneous aspect of the rim did not compromise arthroscopic reparability whereas a heterogeneous aspect of the axial fragment indicated an irreparable meniscus. The described MRI criteria can predict meniscus reparability. Their accuracy is limited for lateral meniscus lesions close to the popliteal hiatus and for very young active patients in whom repair of whiteâwhite lesions can be attempted. Longitudinal full-thickness meniscus lesions are a good indication for repair in young active patients
Toxi-infection alimentaire collective Ă Salmonella Enteritidis suite Ă la consommation de viande de sanglier
International audienc
Tubulointerstitial nephropathies in HIV-infected patients over the past 15 years: a clinico-pathological study.
International audienceBACKGROUND AND OBJECTIVES: The therapy and outcome of HIV infection have dramatically changed over the last 15 years, resulting in a change in renal complications. This study analyzed the characteristics of HIV-infected patients and biopsy-proven tubulointerstitial nephropathies to define disease patterns and therapeutic implications. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A clinico-pathologic retrospective study of 59 consecutive renal biopsies showing predominant tubular and/or interstitial lesions in HIV-infected patients referred to the nephrology department between 1995 and 2011 was performed. HIV-associated nephropathy and vascular diseases were excluded from the study. RESULTS: Tubulointerstitial nephropathies accounted for 26.6% of 222 native renal biopsies performed in HIV-infected patients. Two pathologic groups were analyzed, tubulopathy and interstitial nephritis, which represented 49% and 51% of tubulointerstitial nephropathies, respectively. Most patients presented with AKI (76.3%) and high-grade proteinuria (57.7%). Drug-related nephrotoxicity was the leading cause (52.5%). Alternative etiologies included infections (15.2%), dysimmune disorders (8.5%), malignancies (3.4%), and chronic (10.2%) and acute (10.2%) tubulointerstitial nephropathies of undetermined origin. Tubulopathy was strongly associated with antiretroviral drug toxicity (75.9%) and mostly caused by tenofovir (55.2%), which was associated with proximal tubular dysfunction (87.5%), overt Fanconi's syndrome (37.5%), and nephrogenic diabetes insipidus (12.5%). Interstitial nephritis was associated with a broader spectrum of pathologic lesions and etiologies. CONCLUSIONS: In this series, tubulointerstitial nephropathies accounted for 26.6% of renal diseases in HIV-infected patients. Considering the therapeutic implications of diagnoses of drug toxicity, infection, and dysimmune syndromes, this study underscores the importance of monitoring renal parameters in HIV-infected patients and points to the relevance of kidney biopsy to allow an accurate diagnosis