Validation of ammonia diffusive and pumped samplers in a controlled atmosphere test facility using traceable Primary Standard Gas Mixtures

We report the determination of ammonia (NH3) diffusive sampling rates for six different designs of commercial diffusive samplers (CEH ALPHA sampler, Gradko diffusion tube, Gradko DIFRAM-400, Passam ammonia sampler,and ICS Maugeri Radiello radial sampler (blue and white turbulence barriers)), together with the validation test results for a pumped sampler (CEH DELTA denuder). The devices were all exposed in the UK's National Physical Laboratory's (NPL) controlled atmosphere test facility (CATFAC). For each of the seven diffusive sampler exposure tests there were traceable concentrations of ammonia (in the range 3–25 μgm−3) generated under well-defined conditions of temperature, relative humidity and wind speed, which are applicable to a variety of ambient monitoring environments. The sampler exposure time at each concentration was 28 days, except for the radial devices, which were exposed for 14 days. The work relied on the dilution of newly developed stable Primary Standard Gas Mixtures (PSMs) prepared by gravimetry in passivated gas cylinders as a method of improving the metrological traceability of ammonia measurements. The exposed diffusive samplers were sent blind to the participants for analysis and the reported NH3 concentrations were then compared against the known reference concentration. From the results for each sampler type a diffusive sampling rate was calculated and compared against the rate used routinely by the participants. Some measurement results were in good agreement with the known traceable reference concentration (particularly for one diffusive sampler design (ALPHA)), while other devices exhibited over-reading and under-reading (each with a clear bias). The new diffusive sampling rates determined in the laboratory study were then applied to measurements in a field comparison campaign, and this was found to deliver an improvement in agreement between the different devices deployed

MetNH3 Whim Bog Intercomparison Off-line ammonia metrology intercomparison

There is no regular quality assurance programme for ammonia passive samplers despite widespread use of these samplers across Europe and the rest of the world. In order to improve standards and begin to embed quality assurance in the measurement of ambient ammonia using passive samplers, within the EMRP MetNH3 project a passive sampler intercomparison was planned to enable side-by side exposure of the samplers to varying levels of ammonia in the field. From this experiment and in parallel the NPL CATFAC experiment (also within MetNH3), sufficient information and protocols could be developed. The method and infrastructure developed will then be available for future studies

Literature review on the performance of diffusive samplers for the measurement of ammonia in ambient air and emissions to air

The information in this document has formed the basis from which a new standard on measurements employing ammonia diffusive samplers by CEN TC264 WG11 'Ambient air - Diffusive samplers' is being developed and provides an open reference document for the ammonia passive sampling techniques

The Theia Land Data Centre

International audienceNine French public institutions involved in Earth Observation, environmental studies and scientific research (CEA, CNES, Cirad, CNRS, IGN, INRA, IRD, Irstea and Météo-France), have launched in 2012 the Theia Land Data Centre, pooling their expertise and resources to make satellite data available to the environmental research community and to public policy actors. The Theia primary mission is (i) to build a national space data infrastructure able to produce value-added space data over land and provide services fitted to users’ needs, (ii) to support the sharing of experience and scientific knowledge on methodologies relevant to process and use space data for land thematic issues. To this end, Theia is working to produce data, products, methods and services linked to space observations of continental areas, from local (ecosystem and territory) to global scale, and make them available to the user community. It is backed up by a distributed spatial data infrastructure (SDI), and by scientific expertise hubs in various regions. The SDI links Montpellier (GEOSUD at Maison de la Télédétection) and Toulouse (CNES supported by the CESBIO laboratory, and IGN). The SDI provides already through its portal (www.theia-land.fr) a number of satellite products : yearly coverages at high resolution over the French territory with Spot and Rapid Eye, results from the Take 5 – Spot 4 experiment over 45 sites wordwide from February to June 2013 to simulate Sentinel-2 imagery, time series of orthorectified, atmospherically corrected Landsat data over France. Much more is to come : a first batch of 100 000 images over areas worldwide from the Spot World Heritage programme, provided free of charge for non commercial users, time series of river and lakes height worldwide, atmospherically corrected and monthly composites of Sentinel-2 data over an area equivalent to that of Europe, a new climate record of vegetal variables at global scale with AVHRR, and others. The organisation of science expertise hubs at national level has been initiated. A number of science teams have been created with the goal to prepare processing lines of value added satellite products, in particular from the Sentinel satellites, such as land cover, watered areas, snow areas, imperviousness areas, albedo, vegetal variables at decametric scale, water quality and height, and others

Pôle thématique surfaces continentales THEIA : infrastructure de données pour les scientifiques et les acteurs publics

International audienceUn pôle national de données appelé Theia a été créé fin 2012 avec pour vocation de contribuer à répondre aux besoins de la communauté scientifique nationale et aux acteurs publics en matière de données, de produits, de méthodes et de formation liés à l’observation des surfaces continentales en particulier depuis l’espace. Dix institutions publiques françaises impliquées dans l’observation de la terre et les sciences de l’environnement sont aujourd’hui actifs dans ce pôle. Les objectifs assignés à Theia sont (1) de construire un dispositif commun capable de produire des données spatiales (échelles locale à globale) à valeur ajoutée pour la communauté surfaces continentales et fournir des services en lien avec les besoins des utilisateurs, (2) de favoriser le partage d'expérience et la capitalisation des méthodes, (3) de rendre visible les réalisations nationales à l’échelle européenne et internationale. Le pôle est structuré en une Infrastructure de Données et de Services (IDS) distribuée entre plusieurs acteurs et un réseau de centres d'expertise scientifique (CES) dans les différentes régions métropolitaines et les territoires français d'outre-mer. Les produits fournis par Theia correspondent à des couvertures annuelles d’images satellite du territoire national, des séries temporelles de réflectance de surface, des variables biophysiques (biomasse, les niveaux d'eau, l'humidité de surface, …), des outils de visualisation et de prétraitement des données, des méthodes et des algorithmes de traitement, des guides méthodologiques pour des applications thématiques. Cette infrastructure contribuera à améliorer les connaissances et à soutenir le développement d’applications issues de la recherche utiles aux politiques publiques, pour une meilleure gestion durable des territoires, dans toutes ses dimensions, anthropique, écologique, agricole

Purification of active matrix metalloproteinase catalytic domains and its use for screening of specific stromelysin-3 inhibitors.

The matrix metalloproteinase (MMP) stromelysin-3 (ST3) has been shown to be involved in malignant tumor progression and therefore represents an attractive therapeutical target. In order to screen for ST3 synthetic inhibitors, we have produced and purified the catalytic domain of ST3, matrilysin, stromelysin-2, and membrane type-1 MMP from inclusion bodies in a bacterial system. Our strategy allowed the purification of MMPs directly in the active form, thereby avoidingin vitroactivation. A total of 140,000 synthetic compounds from the Bristol-Myers Pharmaceutical Research Institute chemical deck were tested, using a substrate-based colorimetric enzymatic assay, in which ST3 activity was evaluated through its ability to cleave and inactivate α-1 proteinase inhibitor. One ST3 inhibitor belonging to the cephalosporin family of antibiotics was thereby identified

Le pôle thématique surfaces continentales THEIA

International audienceNeuf institutions publiques françaises impliquées dans l’observation de la terre et les sciences de l’environnement ont créé fin 2012 un pôle national de données appelé THEIA (fille d’Ouranos – le Ciel – et de Gaïa – la Terre), structure scientifique et technique ayant pour vocation de contribuer à répondre aux besoins de la communauté scientifique nationale en matière de données, de produits, de méthodes et de formation liés à l’observation des surfaces continentales en particulier depuis l’espace. Les objectifs assignés à Theia sont (1) de construire un dispositif commun capable de produire des données spatiales (échelles locale à globale) à valeur ajoutée pour la communauté surfaces continentales et fournir des services en lien avec les besoins des utilisateurs, (2) de favoriser le partage d'expérience et la capitalisation des méthodes, (3) de rendre visible les réalisations nationales à l’échelle européenne et internationale. Le pôle est structuré en un Centre de Gestion et de Traitement des Données (CGTD) distribué entre plusieurs acteurs et un réseau de centres d'expertise scientifique (CES) dans les différentes régions métropolitaines et les territoires français d'outre-mer. Les produits fournis par Theia correspondent à des couvertures annuelles d’images satellite du territoire national, des séries temporelles de réflectance de surface, des variables biophysiques (biomasse, les niveaux d'eau, l'humidité de surface, …), des outils de visualisation et de prétraitement des données, des méthodes et des algorithmes de traitement, des guides méthodologiques pour des applications thématiques. Cette infrastructure contribuera à améliorer les connaissances et à soutenir le développement d’applications issues de la recherche utiles aux politiques publiques, pour une meilleure gestion durable des territoires, dans toutes ses dimensions, anthropique, écologique, agricole