13 research outputs found

    Electrical semiconduction modulated by light in a cobalt and naphthalene diimide metal-organic framework

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    Metal–organic frameworks (MOFs) have emerged as an exciting class of porous materials that can be structurally designed by choosing particular components according to desired applications. Despite the wide interest in and many potential applications of MOFs, such as in gas storage, catalysis, sensing and drug delivery, electrical semiconductivity and its control is still rare. The use and fabrication of electronic devices with MOF-based components has not been widely explored, despite significant progress of these components made in recent years. Here we report the synthesis and properties of a new highly crystalline, electrochemically active, cobalt and naphthalene diimide-based MOF that is an efficient electrical semiconductor and has a broad absorption spectrum, from 300 to 2500 nm. Its semiconductivity was determined by direct voltage bias using a four-point device, and it features a wavelength dependant photoconductive–photoresistive dual behaviour, with a very high responsivity of 2.5 × 105 A W−1

    J Ultrasound Med

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    Chest CT is the reference test for assessing pulmonary injury in suspected or diagnosed COVID-19 with signs of clinical severity. This study aimed to evaluate the association of a lung ultrasonography score and unfavorable clinical evolution at 28 days. The eChoVid is a multicentric study based on routinely collected data that was conducted in 8 emergency units in France; patients were included between March 19, 2020 and April 28, 2020 and underwent lung ultrasonography, a short clinical assessment by 2 emergency physicians blinded to each other's assessment, and chest CT. Lung ultrasonography consisted of scoring lesions from 0 to 3 in 8 chest zones, thus defining a global score (GS) of severity from 0 to 24. The primary outcome was the association of lung damage severity as assessed by the GS at day 0 and patient status at 28 days. Secondary outcomes were comparing the performance between GS and CT scan and the performance between a new trainee physician and an ultrasonography expert in scores. For the 328 patients analyzed, the GS showed good performance in predicting clinical worsening at 28 days (area under the receiver operating characteristic curve [AUC] 0.83, sensitivity 84.2%, specificity 76.4%). The GS showed good performance in predicting the CT severity assessment (AUC 0.84, sensitivity 77.2%, specificity 83.7%). A lung ultrasonography GS is a simple tool that can be used in the emergency department to predict unfavorable assessment at 28 days in patients with COVID-19

    Di(Ό-oxo) Binuclear Manganese(III,IV) Poly(bipyridyl) Complexes Bearing Four Ruthenium(II) Photoactive Units: Synthesis, Characterization, and Photoinduced Electron-Transfer Properties

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    International audienceIn order to model the photoinduced electron-transfer reactions from the manganese cluster to the photoactive P680 chlorophylls in photosystem II, three heterohexanuclear complexes, [Mn2III,IVO2{RuII(bpy)2(Ln)}4]11+ [bpy = 2,2'-bipyridine, n = 2 (1a), 4 (1b), 6 (1c)], in which one MnIII,IV(ÎŒ-O)2 center is covalently linked to four RuII(bpy)3-like moieties by bridged bis(bipyridine) Ln ligands, have been synthesized and characterized. The electrochemical, photophysical, and photochemical properties of these complexes have been investigated in CH3CN. The cyclic voltammograms and rotating-disk electrode curves of the three complexes show the presence of two very close successive reversible oxidation processes corresponding to the Mn2III,IV/Mn2IV,IV and RuII/RuIII redox couples (estimated E1/2 ≈ 0.82 and 0.90 V, respectively). The lower potential of the Mn2III,IV subunit compared to those of the RuII moieties indicates that the RuIII species can act as an efficient oxidant toward the Mn2III,IV core. The two oxidized forms of the complexes [Mn2IV,IVO2{RuII(bpy)2(Ln)}4]12+ (2a-c) and [Mn2IV,IVO2{RuIII(bpy)2(Ln)}4]16+ (3a-c) obtained in good yields (>90% for 2a-c and >85% for 3a-c) by sequential electrolyses are very stable. Photophysical studies show that the 3MLCT excited state of the Ru(bpy)3 centers is moderately quenched by the Mn2III,IV(ÎŒ-O)2 core (15-25% depending on the length of the bridging alkyl chain). Nevertheless, this energy transfer can be easily short-circuited in the presence of an external irreversible electron acceptor like the (4-bromophenyl)diazonium cation, by an electron transfer leading, in a stepwise fashion, to the stable one- and five-electron-oxidized species 2a-c and 3a-c, respectively, also in good yields, under continuous irradiation of the solutions. Electro- and photoinduced oxidation experiments have been followed by UV-visible and electron paramagnetic resonance spectroscopy

    Incidence of stroke and socioeconomic neighborhood characteristics: an ecological analysis of Dijon stroke registry.

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    International audienceBACKGROUND AND PURPOSE: Studies have shown higher stroke incidence in areas with higher levels of deprivation. We aimed to determine the pattern of association between various area socioeconomic status (SES) indicators and stroke incidence in specific sex and age groups. METHODS: Data are from the Dijon stroke registry for the period 1995 to 2003. The analyses included 1255 cases aged older than 40 (median age, 76.8). Poisson regression was used to model stroke incidence according to the SES level of 61 small areas. RESULTS: Among women, stroke incidence was higher in neighborhoods with large income inequality (incidence rate ratio, 1.34; P=0.003), higher proportions of unemployed (1.24; P=0.02), of non-French nationals (1.21, P=0.02), and of rented housing (1.31; P=0.03). Areas with a higher proportion of people aged older than 60 were associated with lower stroke incidence (incidence rate ratio, 0.72; P=0.01). Analysis by specific age-groups showed stronger effects among the 60- to 74-year-olds. Among men, no associations between SES and stroke incidence were identified overall but analysis by age groups showed significant effect among the 40- to 59-year-olds. In this age group, incidence rate ratios were 1.47 for unemployment (P=0.01), 1.86 for no car ownership (P=0.02), and 1.56 for income inequality (P=0.01). Among stroke cases, no trend in vascular risk factors prevalence according to area SES was identified. CONCLUSIONS: Variations of stroke incidence were more marked for the SES indicators of wealth and of income inequality. They were apparent at an earlier age in men and showed a stronger gradient among women

    A Planetary Science VO prototype

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    International audienceThe goal of the JRA4 Work Package of Europlanet-RI was to set the basis for a European Virtual Observatory in Planetary Science. The objective in this first step was to save time during searches in big archives and small databases, as well as to facilitate data access and visualization. The system is based on a new access protocol based on TAP, a specific client to query the available services, and intensive recycling of tools developed for the Astronomy VO. Some new databases were also produced in the EuroPlaNet-RI framework and are available in this context. This system should be extensible to all fields of Planetary Science, and open to external data providers

    A Planetary Science VO prototype

    No full text
    International audienceThe goal of the JRA4 Work Package of Europlanet-RI was to set the basis for a European Virtual Observatory in Planetary Science. The objective in this first step was to save time during searches in big archives and small databases, as well as to facilitate data access and visualization. The system is based on a new access protocol based on TAP, a specific client to query the available services, and intensive recycling of tools developed for the Astronomy VO. Some new databases were also produced in the EuroPlaNet-RI framework and are available in this context. This system should be extensible to all fields of Planetary Science, and open to external data providers

    A Planetary Science VO prototype

    No full text
    International audienceThe goal of the JRA4 Work Package of Europlanet-RI was to set the basis for a European Virtual Observatory in Planetary Science. The objective in this first step was to save time during searches in big archives and small databases, as well as to facilitate data access and visualization. The system is based on a new access protocol based on TAP, a specific client to query the available services, and intensive recycling of tools developed for the Astronomy VO. Some new databases were also produced in the EuroPlaNet-RI framework and are available in this context. This system should be extensible to all fields of Planetary Science, and open to external data providers

    Developing the Planetary Science Virtual Observatory

    No full text
    International audienceIn the frame of the Europlanet-RI program, a prototype Virtual Observatory dedicated to Planetary Science has been set up. Most of the activity was dedicated to the definition of standards to handle data in this field. The aim was to facilitate searches in big archives as well as sparse databases, to make on-line data access and visualization possible, and to allow small data providers to make their data available in an interoperable environment with minimum effort. This system makes intensive use of studies and developments led in Astronomy (IVOA), Solar Science (HELIO), and space archive services (IPDA).The current architecture connects existing data services with IVOA or IPDA protocols whenever relevant. However, a more general standard has been devised to handle the specific complexity of Planetary Science, e.g. in terms of measurement types and coordinate frames. This protocol, named EPN-TAP, is based on TAP and includes precise requirements to describe the contents of a data service (Erard et al Astron & Comp 2014). A light framework (DaCHS/GAVO) and a procedure have been identified to install small data services, and several hands-on sessions have been organized already. The data services are declared in standard IVOA registries. Support to new data services in Europe will be provided during the proposed Europlanet H2020 program, with a focus on planetary mission support (Rosetta, Cassini...).A specific client (VESPA) has been developed at VO-Paris (http://vespa.obspm.fr). It is able to use all the mandatory parameters in EPN-TAP, plus extra parameters from individual services. A resolver for target names is also available. Selected data can be sent to VO visualization tools such as TOPCAT or Aladin though the SAMP protocol.Future steps will include the development of a connection between the VO world and GIS tools, and integration of heliophysics, planetary plasma and reference spectroscopic data.The EuroPlaNet-RI project was funded by the European Commission under the 7th Framework Program, grant 228319 "Capacities Specific Programme"

    Developing the Planetary Science Virtual Observatory

    No full text
    International audienceIn the frame of the Europlanet-RI program, a prototype Virtual Observatory dedicated to Planetary Science has been set up. Most of the activity was dedicated to the definition of standards to handle data in this field. The aim was to facilitate searches in big archives as well as sparse databases, to make on-line data access and visualization possible, and to allow small data providers to make their data available in an interoperable environment with minimum effort. This system makes intensive use of studies and developments led in Astronomy (IVOA), Solar Science (HELIO), and space archive services (IPDA).The current architecture connects existing data services with IVOA or IPDA protocols whenever relevant. However, a more general standard has been devised to handle the specific complexity of Planetary Science, e.g. in terms of measurement types and coordinate frames. This protocol, named EPN-TAP, is based on TAP and includes precise requirements to describe the contents of a data service (Erard et al Astron & Comp 2014). A light framework (DaCHS/GAVO) and a procedure have been identified to install small data services, and several hands-on sessions have been organized already. The data services are declared in standard IVOA registries. Support to new data services in Europe will be provided during the proposed Europlanet H2020 program, with a focus on planetary mission support (Rosetta, Cassini...).A specific client (VESPA) has been developed at VO-Paris (http://vespa.obspm.fr). It is able to use all the mandatory parameters in EPN-TAP, plus extra parameters from individual services. A resolver for target names is also available. Selected data can be sent to VO visualization tools such as TOPCAT or Aladin though the SAMP protocol.Future steps will include the development of a connection between the VO world and GIS tools, and integration of heliophysics, planetary plasma and reference spectroscopic data.The EuroPlaNet-RI project was funded by the European Commission under the 7th Framework Program, grant 228319 "Capacities Specific Programme"
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