68 research outputs found

    Textural and knowledge-based lithological classification of remote sensing data in southwestern Prieska sub-basin, Transvaal Supergroup, South Africa

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    TM data and other medium spatial resolution satellite data are used in geological and lithological-mineralogical classification on regular basis, although their usefulness is limited because of relatively coarse spectral resolution. In this contribution, we provide an example for the application of TM data for classification of rocks and minerals within the Neoarchean sedimentary and volcanic basin of Griqualand West, South Africa. An improved methodology is introduced that results in significantly higher classification accuracy. The TM multispectral image and Principal Component analysis (PCA) image of the test area were individually combined with textural features and then classified individually using a maximum-likelihood supervised classification (MLC). Subsequently, the two classified images were integrated, compared and re-classified in a knowledge-based system (KBS) using the generalized supplementary geological map on 1:250,000 scale. With this method, the accuracy was improved from 54.3% to 83.2%, when compared to the former supervised classification. The method integrates the spectral and textural features, greatly contributing to the precision of the lithological classification, mapping and prospecting, in extensive areas where field work is limited by time and cost constrains.The China Scholarship Council (CSC) and to the LMU International Office for supporting Li‟s doctoral research at the Ludwig-Maximilians University München.http://www.elsevier.com/locate/jafrearscihb2016Geolog

    A multi-technology analysis of the 2017 North Korean nuclear test

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    On 3 September 2017 official channels of the Democratic People's Republic of Korea announced the successful test of a thermonuclear device. Only seconds to minutes after the alleged nuclear explosion at the Punggye-ri nuclear test site in the mountainous region in the country's northeast at 03:30:02 (UTC), hundreds of seismic stations distributed all around the globe picked up strong and distinct signals associated with an explosion. Different seismological agencies reported body wave magnitudes of well above 6.0, consequently estimating the explosive yield of the device on the order of hundreds of kT TNT equivalent. The 2017 event can therefore be assessed as being multiple times larger in energy than the two preceding North Korean events in January and September 2016. This study provides a multi-technology analysis of the 2017 North Korean event and its aftermath using a wide array of geophysical methods. Seismological investigations locate the event within the test site at a depth of approximately 0.6&thinsp;km below the surface. The radiation and generation of P- and S-wave energy in the source region are significantly influenced by the topography of the Mt. Mantap massif. Inversions for the full moment tensor of the main event reveal a dominant isotropic component accompanied by significant amounts of double couple and compensated linear vector dipole terms, confirming the explosive character of the event. The analysis of the source mechanism of an aftershock that occurred around 8&thinsp;min after the test in the direct vicinity suggest a cavity collapse. Measurements at seismic stations of the International Monitoring System result in a body wave magnitude of 6.2, which translates to an yield estimate of around 400&thinsp;kT TNT equivalent. The explosive yield is possibly overestimated, since topography and depth phases both tend to enhance the peak amplitudes of teleseismic P waves. Interferometric synthetic aperture radar analysis using data from the ALOS-2 satellite reveal strong surface deformations in the epicenter region. Additional multispectral optical data from the Pleiades satellite show clear landslide activity at the test site. The strong surface deformations generated large acoustic pressure peaks, which were observed as infrasound signals with distinctive waveforms even at distances of 401&thinsp;km. In the aftermath of the 2017 event, atmospheric traces of the fission product 133Xe were detected at various locations in the wider region. While for 133Xe measurements in September 2017, the Punggye-ri test site is disfavored as a source by means of atmospheric transport modeling, detections in October 2017 at the International Monitoring System station RN58 in Russia indicate a potential delayed leakage of 133Xe at the test site from the 2017 North Korean nuclear test.</p

    The evolution of Wide-Area DInSAR: from regional and national services to the European Ground Motion Service

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    This study is focused on wide-area deformation monitoring initiatives based on the differential interferometric SAR technique (DInSAR). In particular, it addresses the use of advanced DInSAR (A-DInSAR) techniques, which are based on large sets of synthetic aperture radar (SAR) and Copernicus Sentinel-1 images. Such techniques have undergone a dramatic development in the last twenty years: they are now capable to process big sets of SAR images and can be exploited to realize a wide-area A-DInSAR monitoring. The study describes several initiatives to establish wide-area ground motion services (GMS), both at county- and region-level. In the second part of the study, some of the key technical aspects related to wide-area A-DInSAR monitoring are discussed. Finally, the last part of the study is devoted to the European ground motion service (EGMS), which is part of the Copernicus land monitoring service. It represents the most important wide-area A-DInSAR deformation monitoring system ever developed. The study describes its main characteristics and its main products. The end of the production of the first EGMS baseline product is foreseen for the last quarter of 202

    Ellipticine and benzo(a)pyrene increase their own metabolic activation via modulation of expression and enzymatic activity of cytochromes P450 1A1 and 1A2

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    Two compounds known to covalently bind to DNA after their activation with cytochromes P450 (CYPs), carcinogenic benzo(a)pyrene (BaP) and an antineoplastic agent ellipticine, were investigated for their potential to induce CYP and NADPH:CYP reductase (POR) enzymes in rodent livers, the main target organ for DNA adduct formation. Two animal models were used in the study: (i) rats as animals mimicking the fate of ellipticine in humans and (ii) mice, especially wild-type (WT) and hepatic POR null (HRN™) mouse lines. Ellipticine and BaP induce expression of CYP1A enzymes in livers of experimental models, which leads to increase in their enzymatic activity. In addition, both compounds are capable of generating DNA adducts, predominantly in livers of studied organisms. As determined by 32P postlabelling analysis, levels of ellipticine-derived DNA adducts formed in vivo in the livers of HRN™ mice were reduced (by up to 65%) relative to levels in WT mice, indicating that POR mediated CYP enzyme activity is important for the activation of ellipticine. In contrast to these results, 6.4 fold higher DNA binding of BaP was observed in the livers of HRN™ mice than in WT mice. This finding suggests a detoxication role of CYP1A in BaP metabolism in vivo. In in vitro experiments, DNA adduct formation in calf thymus DNA was up to 25 fold higher in incubations of ellipticine or BaP with microsomes from pretreated animals than with controls. This stimulation effect was attributed to induction of CYP1A1/2 enzymes, which are responsible for oxidative activation of both compounds to the metabolites generating major DNA adducts in vitro. Taken together, these results demonstrate that by inducing CYP1A1/2, ellipticine and BaP modulate their own enzymatic metabolic activation and detoxication, thereby modulating their either pharmacological (ellipticine) and/or genotoxic potential (both compounds)

    Analysis of benzo[a]pyrene metabolites formed by rat hepatic microsomes using high pressure liquid chromatography: optimization of the method

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    A simple and sensitive method was developed to separate the carcinogenic polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BaP), and six of its oxidation metabolites generated by rat hepatic microsomes enriched with cytochrome P450 (CYP) 1A1, by high pressure liquid chromatography (HPLC). The HPLC method, using an acetonitrile/water gradient as mobile phase and UV detection, provided appropriate separation and detection of both mono- and di-hydroxylated metabolites of BaP as well as BaP diones formed by rat hepatic microsomes and the parental BaP. In this enzymatic system, 3-hydroxy BaP, 9-hydroxy BaP, BaP-4,5-dihydrodiol, BaP-7,8-dihydrodiol, BaP-9,10-dihydrodiol and BaP-dione were generated. Among them the mono-hydroxylated BaP metabolite, 3-hydroxy BaP followed by di-hydroxylated BaP products, BaP-7,8-dihydrodiol and BaP-9,10-dihydrodiol, predominated, while BaP-dione was a minor metabolite. This HPLC method will be useful for further defining the roles of the CYP1A1 enzyme with both in vitro and in vivo models in understanding its real role in activation and detoxification of BaP

    Stream dissolved organic matter in permafrost regions shows surprising compositional similarities but negative priming and nutrient effects

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    Permafrost degradation is delivering bioavailable dissolved organic matter (DOM) and inorganic nutrients to surface water networks. While these permafrost subsidies represent a small portion of total fluvial DOM and nutrient fluxes, they could influence food webs and net ecosystem carbon balance via priming or nutrient effects that destabilize background DOM. We investigated how addition of biolabile carbon (acetate) and inorganic nutrients (nitrogen and phosphorus) affected DOM decomposition with 28-day incubations. We incubated late-summer stream water from 23 locations nested in seven northern or high-altitude regions in Asia, Europe, and North America. DOM loss ranged from 3% to 52%, showing a variety of longitudinal patterns within stream networks. DOM optical properties varied widely, but DOM showed compositional similarity based on Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) analysis. Addition of acetate and nutrients decreased bulk DOM mineralization (i.e., negative priming), with more negative effects on biodegradable DOM but neutral or positive effects on stable DOM. Unexpectedly, acetate and nutrients triggered breakdown of colored DOM (CDOM), with median decreases of 1.6% in the control and 22% in the amended treatment. Additionally, the uptake of added acetate was strongly limited by nutrient availability across sites. These findings suggest that biolabile DOM and nutrients released from degrading permafrost may decrease background DOM mineralization but alter stoichiometry and light conditions in receiving waterbodies. We conclude that priming and nutrient effects are coupled in northern aquatic ecosystems and that quantifying two-way interactions between DOM properties and environmental conditions could resolve conflicting observations about the drivers of DOM in permafrost zone waterways

    Landslide databases in the Geological Surveys of Europe

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    Acceso electrónico sólo desde el IGMELandslides are one of the most widespread geohazards in Europe, producing significant social and economic impacts. Rapid population growth in urban areas throughout many countries in Europe and extreme climatic scenarios can considerably increase landslide risk in the near future. Variability exists between European countries in both the statutory treatment of landslide risk and the use of official assessment guidelines. This suggests that a European Landslides Directive that provides a common legal framework for dealing with landslides is necessary. With this long-term goal in mind, this work analyzes the landslide databases from the Geological Surveys of Europe focusing on their interoperability and completeness. The same landslide classification could be used for the 849,543 landslide records from the Geological Surveys, from which 36% are slides, 10% are falls, 20% are flows, 11% are complex slides, and 24% either remain unclassified or correspond to another typology. Most of them are mapped with the same symbol at a scale of 1:25,000 or greater, providing the necessary information to elaborate European-scale susceptibility maps for each landslide type. A landslide density map was produced for the available records from the Geological Surveys (LANDEN map) showing, for the first time, 210,544 km2 landslide-prone areas and 23,681 administrative areas where the Geological Surveys from Europe have recorded landslides. The comparison of this map with the European landslide susceptibility map (ELSUS 1000 v1) is successful for most of the territory (69.7%) showing certain variability between countries. This comparison also permitted the identification of 0.98 Mkm2 (28.9%) of landslide-susceptible areas without records from the Geological Surveys, which have been used to evaluate the landslide database completeness. The estimated completeness of the landslide databases (LDBs) from the Geological Surveys is 17%, varying between 1 and 55%. This variability is due to the different landslide strategies adopted by each country. In some of them, landslide mapping is systematic; others only record damaging landslides, whereas in others, landslide maps are only available for certain regions or local areas. Moreover, in most of the countries, LDBs from the Geological Surveys co-exist with others owned by a variety of public institutions producing LDBs at variable scales and formats. Hence, a greater coordination effort should be made by all the institutions working in landslide mapping to increase data integration and harmonization.Earth Observation and Geohazards Expert Group (EOEG), EuroGeoSurveys, the Geological Surveys of Europe, BélgicaGeohazards InSAR Laboratory and Modeling Group, Instituto Geológico y Minero de España, EspañaRisk and Prevention Division, Bureau de Recherches Géologiques et Minières, FranciaEngineering Geology Department, Institute of Geology and Mineral Exploration, GreciaGeoHazard team, Geological Institute of Romania, RumaníaGeological Survey of Slovenia, EsloveniaCroatian Geological Survey, CroaciaItalian Institute for Environmental Protection and Research, Geological Survey of Italy, ItaliaSwiss Federal Office for the Environment, SuizaGeological Survey of Austria, AustriaPolish Geological Institute, National Research Institute, PoloniaGeological Survey of Ireland, IrlandaCzech Geological Survey, República ChecaFederal Institute for Geosciences and Natural Resources, AlemaniaGeological Survey of Norway, NoruegaCyprus Geological Survey, ChipreGeological Survey of Sweden, SueciaInstitut Cartogràfic i Geològic de Catalunya, EspañaBritish Geological Survey, Reino UnidoGeological Survey of Slovakia, EslovaquiaGeological Survey of Lithuania, LituaniaFederalni zavod za geologiju, Bosnia y HerzegovinaGeological Survey of Estonia, EstoniaLaboratório Nacional de Energia e Geologia, PortugalGeological Survey of Hungary, HungríaNorwegian Water and energy Directorate of Norway, Norueg

    Pitfalls of nurses' work in patient care during treatment by continuous elimination method

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    Problematika kontinuálních eliminačních metod a činnosti s ní související na jednotkách intenzivní péče jsou častou náplní práce všeobecných sester. V mnoha případech ale zdravotničtí pracovníci, a to zejména v situacích, kdy tuto činnost nevykonávají často či pravidelně, tápou a nejsou si zcela jisti v některých intervencích. I proto je vhodné, aby zdravotnická pracoviště, kde se intervence v souvislosti s touto metodou vykonávají, měla vhodný pracovní postup či standard dostupný všem zainteresovaným. V našem výzkumném šetření jsme se zaměřili na identifikaci potenciálních rizik, problémů a absenci potřebných informací, které mohou pomoci zdravotníkům ke zvládnutí dané problematiky, a budou jim oporou v jednotlivých intervencích souvisejících s kontinuální eliminační metodou.The issues of continual elimination methods and activity associated with them on intensive care units are frequent content of general nurses’ work. But in many cases the health workers, and especially in situations when they do not perform this activity often or frequently, fumble and are not completely certain in some interventions. And wherefore it is convenient for medical facilities where the interventions in accordance with this method are performed to have an appropriate working procedure or a standardization available to all involved personnel. In our research, we focused on the identification of potential risks, problems and absence of desired information which may help health workers to manage given issues and will be a support to them in individual interventions related to continual elimination method

    Aspekte des Bodenbewegungsdienstes Deutschlands

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    Deformationen der Erdoberfläche sind das Ergebnis geologischer Prozesse oder anthropogener Maßnahmen oder deren Kombination. Beispiele sind tektonische Bewegungen, Hangrutschungen, Subrosions-, Auslaugungs- und Quellprozesse. Die Deformationen treten darüber hinaus in Folge von Öl- und Gasextraktionen, Grundwasserbewirtschaftung, Verpressungen, Tunnelauffahrungen, Baugrubenmanagement oder Bergbau auf. Verformungen der Erdoberfläche lassen sich seit fast 30 Jahren millimetergenau mit der satellitengestützten Radarinterferometrie identifizieren und monitoren. Die Einsatzfähigkeit und Genauigkeit des Verfahrens ist durch zahlreiche nationale und internationale Forschungsprojekte, Pilotstudien und Anwendungsfälle nachgewiesen. Verursachen Bodenbewegungen Schäden, müssen die Ursachen ergründet und Fragen der Verantwortung und Kostenübernahme geklärt werden. Seit dem Start der Radarsatelliten Sentinel 1A und B des europäischen Copernicus Programms stehen flächendeckend umfangreiche Daten zum kostenfreien Download zur Verfügung. Unter Nutzung von Open-Source Software können inzwischen von zahlreichen Akteuren und Interessengruppen Deformationsdarstellung über die Erdoberfläche gewonnen und verbreitet werden. Daraus erwächst die Notwendigkeit für Verformungen der Erdoberfläche unabhängige, qualitätsgesicherte und allseits anerkannte Rahmenwerte, Entscheidungsgrundlagen und Prozessketten bereitzuhalten. Daher baut die BGR den satellitengestützten nationalen BodenBewegungsdienst Deutschland (BBD) auf (Kalia et al., 2017). Zurzeit sind zwei Datensätze des aufsteigenden und absteigenden Orbits der Copernicus-Satellitenmission Sentinel-1 prozessiert. Sie decken als konsistente Datensätze die gesamte Fläche Deutschlands ab. Im Beitrag wird der Sachstand des BBD präsentiert und ein Blick auf die ersten bundesweiten Datensätze mit Bezug zu geotechnischen und bergbaulichen Anwendungen geworfen. Darüber hinaus wird schlaglichtartig der Einsatz der Radarinterferometrie in Europa, auch Deutschland betreffend, beleuchtet
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