57 research outputs found

    Evaluation de la pollution de l'eau par les Ethers de glycol (Eg)

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    Les Eg sont des substances largement utilisées dans les produits domestiques et industriels. Certains sont des toxiques, principalement de la reproduction et du sang. Leur présence dans les milieux aqueux a été peu recherchée, car leur polarité fait que les méthodes classiques sont inadéquates pour les détecter. Une méthode d'extraction de type SPME (Solid Phase Micro Extraction), couplée avec une analyse CG/FID ou CG/SM a été mise au point et utilisée pour évaluer la pollution dans un certain nombre de milieux aquatiques. Le traitement dans les stations diminue fortement la pollution de l'eau, mais certains pics de pollution subsistent. Les indications relatives à la pollution des nappes montrent qu'une étude plus systématique est nécessaire, notamment autour de décharges ayant reçu des déchets contenant des Eg

    Environmental benzene exposure assessment for parent-child pairs in Rouen, France

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    International audienceThere is a lack of data on environmental benzene exposure in children. In this study, we compared personal benzene exposure and inhalation uptake in a group of children to those of their parents. We also compared levels of urinary benzene metabolites, trans, trans-muconic acid (MA) and hydroquinone (HQ), for those two groups, and assessed the correlation between personal benzene exposure and urinary MA and HQ concentrations. The study was performed on 21, 2-3-year-old children and their parents recruited on a voluntary basis among non-smokers from the three largest day-care centers of the town of Rouen in France. Average benzene concentrations were measured over 5 consecutive days with diffusive. samplers. The following simultaneous measurements were carried out: personal exposure of the parents, concentrations inside and outside the day care centers, and inside the volunteer's bedrooms. Morning and evening urine samples were collected during the same period. Benzene personal exposure levels were 14.4 +/- 7.7 mug/m(3) and 11.09 +/- 6.15 mug/m(3) in parents and children, respectively. Benzene inhalation uptake estimates were 2.51 +/- 1.23 mug/kg/day in the group of parents and 5.68 +/- 3.17 mug/kg/day in the group of children. Detectable levels of MA and HQ were found in 85% and 100% of the samples, respectively. Intra-individual variation of urinary MA and HQ concentrations expressed as a coefficient of variation (CV) ranged from 63 to 232% and from 13 to 144%, respectively. Mean values of MA and HQ (in mg/g creatinine) were 1.6- and 1.8-fold higher in the group of children than in the group of parents (P=0.008 and P<0.0001, respectively). Significant correlations between metabolites levels and benzene were not found

    Low loss coatings for the VIRGO large mirrors

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    présentée par L. PinardThe goal of the VIRGO program is to build a giant Michelson type interferometer (3 kilometer long arms) to detect gravitational waves. Large optical components (350 mm in diameter), having extremely low loss at 1064 nm, are needed. Today, the Ion beam Sputtering is the only deposition technique able to produce optical components with such performances. Consequently, a large ion beam sputtering deposition system was built to coat large optics up to 700 mm in diameter. The performances of this coater are described in term of layer uniformity on large scale and optical losses (absorption and scattering characterization). The VIRGO interferometer needs six main mirrors. The first set was ready in June 2002 and its installation is in progress on the VIRGO site (Italy). The optical performances of this first set are discussed. The requirements at 1064 nm are all satisfied. Indeed, the absorption level is close to 1 ppm (part per million), the scattering is lower than 5 ppm and the R.M.S. wavefront of these optics is lower than 8 nm on 150 mm in diameter. Finally, some solutions are proposed to further improve these performances, especially the absorption level (lower than 0.1 ppm) and the mechanical quality factor Q of the mirrors (thermal noise reduction)

    Large-Scale Recombinant Production of the SARS-CoV-2 Proteome for High-Throughput and Structural Biology Applications

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    The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortium’s collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com, we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form

    Some experiences of atmospheric PAH monitoring in France

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    International audienceOver recent years INERIS has carried out PAH measurements in ambient air. The aim of these studies is to propose methods which could be used by air quality monitoring networks in order to meet future regulations. INERIS used high volume samplers to collect PAH in particulate phase and in gaseous phase, and analysed 17 compounds. During field campaigns in urban sites, INERIS worked in close relation with LHVP, which has an experience in the low volume samplers

    Improved extraction of glycol ethers from water by solid-phase micro extraction by carboxen polydimethylsiloxane-coated fiber

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    International audience15 glycol ethers can be extracted from water by solid-phase microextraction with a carboxen-polydimethylsiloxane and separated by GC a Carbowax column. Water containing 15 glycol ethers at concentrations 0.1-10 mg.L-1 is saturated at ambient temperature with NaCl. A carboxen-polydimethylsiloxane-coated fiber is then exposed to the liquid for 20 min and then automatically injected into a capillary GC injection port. Calibration curves were linear for different glycol ethers in the range 0.1-10 mg.L-1 Detection limits of each component of the mixture of glycol ethers between 50-500 mu g.L-1. The SPME method with direct immersion in water results in better sensivity than methods based on liquid-liquid extractio

    Forum Santé & Environnement

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    Fédération des Maisons Médicales et des Collectifs de santé francophone – Institut Bruxellois pour la gestion de l’Environnementinfo:eu-repo/semantics/publishe
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