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See detailA remote controlled XRF system for field analysis of cultural heritage objects
Hocquet, François-Philippe ULg; Garnir, Henri-Pierre ULg; Marchal, André ULg et al

in X-Ray Spectrometry [=XRS] (2008), 37(4), 304-308

X-ray fluorescence (XRF) is a nondestructive, multielemental, fast and cost-effective analysis technique. It can be applied in a nonvacuum environment directly on the samples without any preparation. As ... [more ▼]

X-ray fluorescence (XRF) is a nondestructive, multielemental, fast and cost-effective analysis technique. It can be applied in a nonvacuum environment directly on the samples without any preparation. As archaeological and historical objects are often unique and may not be easily movable, a mobile XRF detector system allowing in situ analysis is ideally suited for archaeometric applications. A mobile system was designed and built at the IPNAS laboratory to provide such analyses. The system includes an industrial grade x-ray generator which supplies the primary x-ray beam, an air-cooled silicon rift Detector detector (SDD) with a 5-mm(2) active area. The data acquisition system measures the energy and the intensity of the secondary fluorescence x-rays. The detector signal is amplified and analyzed by a multichannel recorder coupled to a microcomputer running JavaSpectre which visualizes and analyzes spectra obtained from the detector. The detection head, containing the detector, the x-ray tube and its power supply, are fixed on a movable platform allowing independent vertical and horizontal movement. All displacements are controlled by a hand-held personal digital assistant (PDA) (Palm) which exchanges data with microcontrollers embedded in the system providing a very precise positioning of the detector over a surface of many square meters. This system control, as well as a typical application of this XRF spectrometer for analyzing pigment composition of a wall painting, will be described. Copyright (C) 2008 John Wiley & Sons, Ltd. [less ▲]

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See detailRemote sensing and near surface structures and circulation in the Ligurian Sea off Corsica
Djenidi, Salim ULg

in Bulletin de la Société Royale des Sciences de Liège (1985), 54(4-5), 277-284

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See detailRemote Sensing and Urban Analysis
Donnay, Jean-Paul ULg; Barnsley, Mike J.; Longley, Paul A.

Book published by Taylor & Francis (2001)

One of the key geographical developments over the last two centuries has been that of urbanisation. In recent years this has exploded globally, particularly in developing countries. It is essential for ... [more ▼]

One of the key geographical developments over the last two centuries has been that of urbanisation. In recent years this has exploded globally, particularly in developing countries. It is essential for governments, planners and researchers in geography and allied fields to understand this process and the main way of being able to do this is to accurately map these changes. The main method of this mapping is Remote Sensing.This up-to-date analysis of the area looks at a wide range of methodologies currently being used to produce and analyse remotely sensed data of urban areas. The authors examine the various techniques used to extract information from digital, multispectral images of urban areas. Donnay and Barnsley then go on to look at the identification of urban forms, the delineation of agglomerations and the development of urban morphology, considering the analysis of integrated data sets and surface models and going on to look at the estimation of human population levels. [less ▲]

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See detailRemote Sensing and Urban Analysis - Introduction
Donnay, Jean-Paul ULg; Barnsley, Mike; Longley, Paul

in Donnay, Jean-Paul; Barnsley, Mike; Longley, Paul (Eds.) Remote Sensing and Urban Analysis (2001)

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See detailRemote Sensing and Urban Analysis : A Research Agenda
Longley, Paul; Barnsley, Mike; Donnay, Jean-Paul ULg

in Donnay, Jean-Paul; Barnsley, Mike; Longley, Paul (Eds.) Remote Sensing and Urban Analysis (2001)

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See detailRemote Sensing and Urban Change
Donnay, Jean-Paul ULg; Barnsley, Mike

in GISDATA Newsletter (1995), 6

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See detailRemote sensing assessement of irrigated areas extension in the Kou watershed
Traore, Farid ULg; Tychon, Bernard ULg

Scientific conference (2010, January 12)

The Kou watershed is a geographical space having important water resources, whose are used between: drinking water supply of Bobo-Dioulasso city (Burkina-Faso’s second most important city) and surrounding ... [more ▼]

The Kou watershed is a geographical space having important water resources, whose are used between: drinking water supply of Bobo-Dioulasso city (Burkina-Faso’s second most important city) and surrounding localities; agriculture through very important irrigated surfaces; industry; fauna and flora preservation, through a minimal sanitary debit guaranteed. Since some decades, one observes more and more increased pressure on Kou water resources. From an agricultural point of view, a comparative visual observation of irrigated surfaces during the years 1980 and during years 2000 shows an increase of surfaces. It would be then appropriate to establish a potential of irrigation of the set of available water resources in order to estimate maximal irrigable surfaces by water resources. Thus, this study has for goal the evaluation of Kou watershed irrigated zones surface, with the help of remote sensing. In order to facilitate irrigated zones detection, the study will focused on the period between January and June, where all cultures are irrigated with Kou watershed surface water and/or groundwater. The chosen methodology is images classification in order to extract irrigated zones surface. We had for this study a set of images and various data: Landsat-4 TM, Landsat-5 TM, Landsat-7 ETM+, SPOT 5, aerial views, agro meteorological data, cartographic data (GIS), data investigation reports, etc. Because of images various origins, we conducted images pretreatment that essentially consisted in image reflectance calibration. This operation appears to be indispensable when working with images from coming different sensors. Classification methods that we used are: a maximum likelihood classification, then a decision tree classification applied to images for which vegetation index (NDVI) has been calculated. The later classification method has been introduced in order to permit a better discrimination between natural vegetation and crops which can often react in similar spectral ranges. This method is based on threshold detection of vegetation classes. Classification methods used allowed us to estimate until a certain point irrigated surfaces, without having, however, a finer information. With 30 m spatial resolution images covering a survey zone with "reduced" to "mean" agricultural lands size, it is sometimes enough difficult to discern natural vegetation pixels from crop pixels. So, we should have considered mixed classes of pixels that strongly skewed our final results. The overall accuracy of our classifications are between 70% and 90%, with Kappa coefficients between 0.4 and 0.85. These Kappa coefficients our results between "tolerable" and "good". However, our evaluations seem to be near enough of those gotten by the means of hydro agricultural inventories led on the same zone. The committed mistakes remain in an interval of +/-20%. [less ▲]

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See detailA Remote Sensing Based Calibration Framework for the MOLAND Urban Growth Model of Dublin
Van de Voorde, Tim; van der Kwast, Johannes; Canters, Frank et al

in International Journal of Agricultural and Environmental Information Systems (2012), 3(2), 1-21

Land-use change models are useful tools for assessing and comparing the environmental impact of alternative policy scenarios. Their increasing popularity as spatial planning instruments also poses new ... [more ▼]

Land-use change models are useful tools for assessing and comparing the environmental impact of alternative policy scenarios. Their increasing popularity as spatial planning instruments also poses new scientific challenges, such as correctly calibrating the model. The challenge in model calibration is twofold: obtaining a reliable and consistent time series of land-use information and finding suitable measures to compare model output to reality. Both of these issues are addressed in this paper. The authors propose a model calibration framework that is supported by information on urban form and function derived from medium-resolution remote sensing data through newly developed spatial metrics. The remote sensing derived maps are compared to model output of the same date for two model scenarios using well-known spatial metrics. Results demonstrate a good resemblance between the simulation output and the remote sensing derived maps. [less ▲]

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See detailRemote sensing of colour, temperature and salinity – new challenges and opportunities
Alvera Azcarate, Aïda ULg; Ruddick, Kevin; Minnett, Peter

in Remote Sensing of Environment (in press)

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See detailRemote Sensing of Suspended Particulate Matter in Turbid Waters: State of the Art and Future Perspectives.
Ruddick, Kevin; Nechad, Bouchra; Park, Youngje et al

Conference (2008, October)

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See detailRemote sensing of the energy of auroral electrons in Saturn’s atmosphere: Hubble and Cassini spectral observations
Gérard, Jean-Claude ULg; Gustin, Jacques ULg; Pryor, Wayne et al

in Icarus (2013), 223

Saturn’s north ultraviolet aurora has been successfully observed twice between March and May 2011 with the STIS long-slit spectrograph on board the Hubble Space Telescope. Spatially resolved spectra at ... [more ▼]

Saturn’s north ultraviolet aurora has been successfully observed twice between March and May 2011 with the STIS long-slit spectrograph on board the Hubble Space Telescope. Spatially resolved spectra at ∼12 Å spectral resolution have been collected at different local times from dawn to dusk to determine the amount of hydrocarbon absorption. For this purpose, the HST telescope slewed across the auroral oval from mid-latitudes up to beyond the limb while collecting spectral data in the timetag mode. Spectral images of the north ultraviolet aurora were obtained within minutes and hours with the UVIS spectrograph on board Cassini. Several daytime sectors and one nightside location were observed and showed signatures of weak absorption by methane present in (or above) the layer of the auroral emission. No absorption from other hydrocarbons (e.g. C2H2) has been detected. For the absorbed spectra, the overlying slant CH4 column varies from 3x1015 to 2x1016 cm-2, but no clear dependence on local time is identified. A Monte Carlo electron transport model is used to calculate the vertical distribution of the H2 emission and to relate the observed spectra to the energy of the primary auroral electrons. Assuming electron precipitation with a Maxwellian energy distribution into a standard model atmosphere, we find that the mean energy ranges from less than 3 to ∼10 keV. These results are compared with previous determinations of the energy of Saturn’s aurora based on ultraviolet spectra and limb images. We conclude that the energies derived from spectral methods indicate a wide range of electron energies while the nightside limb images suggest that the auroral precipitation is consistently soft. We emphasize the need for more realistic model atmospheres with temperature and hydrocarbon distributions appropriate to high-latitude conditions. [less ▲]

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See detailRemote sensing of the proton aurora characteristics from IMAGE-FUV
Bisikalo, D. V.; Shematovich, V. I.; Gérard, Jean-Claude ULg et al

in Annales Geophysicae [= ANGEO] (2003), 21

The combination of simultaneous global images of the north polar region obtained with the IMAGE-FUV imaging system makes it possible to globally map the properties of the electron and proton auroral ... [more ▼]

The combination of simultaneous global images of the north polar region obtained with the IMAGE-FUV imaging system makes it possible to globally map the properties of the electron and proton auroral precipitation. The SI12 imager, which observes the Doppler-shifted Lyman-a [less ▲]

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See detailRemotely sensed data contributes to GIS socioeconomic analysis
Donnay, Jean-Paul ULg

in GIS-Europe (1992), 1(10), 38-41

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See detailRemotely sensed seasonal dynamics of phytoplankton in the Ligurian Sea in 1997-1999
Nezlin, N. P.; Lacroix, G.; Kostianoy, A. G. et al

in Journal of Geophysical Research. Oceans (2004), 109(C07013),

[1] Remotely sensed data and a one-dimensional hydrophysical model were used to study the seasonal dynamics of surface plant pigments concentration in the Ligurian-Provencal basin. The variations of ... [more ▼]

[1] Remotely sensed data and a one-dimensional hydrophysical model were used to study the seasonal dynamics of surface plant pigments concentration in the Ligurian-Provencal basin. The variations of phytoplankton biomass were estimated from the observations of the Coastal Zone Color Scanner ( 1978 - 1986) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) ( September 1997 to October 1999) radiometers. The factors of physical environment analyzed included remotely sensed sea surface temperature ( from advanced very high resolution radiometers), wind, air temperature, and atmospheric precipitation. The Geohydrodynamics and Environment Research (GHER) model was used to explain the observed correlations between the physical forcing and the response of phytoplankton biomass. The general pattern of phytoplankton seasonal dynamics was typical to subtropical areas: maximum biomass during cold season from October to April and low biomass during summer months. The intensity of winter/spring bloom significantly varied during different years. The correlation was revealed between the summer/autumn air temperature contrast ( expressed as the difference between the air temperatures in August and in November) and the maximum monthly averaged surface chlorophyll concentration during the subsequent winter/spring bloom. The features of seasonal dynamics of phytoplankton are regulated by the physical impacts influencing water stratification. The difference between two seasonal cycles ( from September 1997 to October 1999) illustrates the response of phytoplankton growth to local meteorological conditions. In March - April 1999 the vernal bloom was much more pronounced; it resulted from deeper winter cooling and more intensive winter convection. Heating of surface water layer, wind mixing, and freshwater load with rains and river discharge either stimulate or depress the development of phytoplankton, depending on what limiting environmental factor ( light or nutrient limitation) prevailed. [less ▲]

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See detailRemoval of Androgens and Estrogens from Water by Reactive Materials
Kai, Cai; Phillips, D. H.; Elliott, Christian et al

in Journal of Water Resource and Protection (2010), 2(11), 990-993

Nowadays, endocrine disruptor compounds in the water system have become a concern due to the risk of contamination to wild life and humans even at the nanogram level. Excess estrogens and androgens are a ... [more ▼]

Nowadays, endocrine disruptor compounds in the water system have become a concern due to the risk of contamination to wild life and humans even at the nanogram level. Excess estrogens and androgens are a major contributor group of endocrine compounds. Statistical surveys have shown that dairy farms contribute to over 90% of the total estrogens in the UK and US. An analytical system is being developed to assess the efficiency of reactive materials to remove target hormonal contaminants from dairy farm effluent. This can be achieved using reporter gene assays (RGAs) to detect low level steroid hormones. A preliminary study comparing the efficiency of granular activated carbon, zero-valent iron, and organoclay was carried out using bench-scale evaluations in negative control HPLC water. Their potential ability to remove testosterone and 17-β- estradiol spiked at reported environmental levels was measured by androgenic and estrogenic luminescent reporter assay respectively. [less ▲]

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See detailRemoval of Androgens and Estrogens from Water by Reactive Materials
Kai, Cai; Phillips, D. H.; Elliott, Chris et al

in 2010 4th International Conference on Bioinformatics and Biomedical Engineering (iCBBE 2010) (2010)

Nowadays, endocrine disruptor compounds in the water system have become a concern due to the risk of contamination to wild life and humans even at the nanogram level. Excess estrogens and androgens are a ... [more ▼]

Nowadays, endocrine disruptor compounds in the water system have become a concern due to the risk of contamination to wild life and humans even at the nanogram level. Excess estrogens and androgens are a major contributor group of endocrine compounds. Statistical surveys have shown that dairy farms contribute to over 90% of the total estrogens in the UK and US. An analytical system is being developed to assess the efficiency of reactive materials to remove target hormonal contaminants from dairy farm effluent. This can be achieved using reporter gene assays (RGAs) to detect low level steroid hormones. A preliminary study comparing the efficiency of granular activated carbon, zero-valent iron, and organoclay was carried out using bench-scale evaluations in negative control HPLC water. Their potential ability to remove testosterone and 17- beta -estradiol spiked at reported environmental levels was measured by androgenic and estrogenic luminescent reporter assay respectively. [less ▲]

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See detailRemoval of C-terminal Src kinase from the immune synapse by a new binding protein
Rahmouni, Souad ULg; Vang, Torkel; Alonso, Andres et al

in Molecular and Cellular Biology (2005), 25(6), 2227-2241

The Csk tyrosine kinase negatively regulates the Src family kinases Lek and Fyn in T cells. Engagement of the T-cell antigen receptor results in a removal of Csk from the lipid raft-associated ... [more ▼]

The Csk tyrosine kinase negatively regulates the Src family kinases Lek and Fyn in T cells. Engagement of the T-cell antigen receptor results in a removal of Csk from the lipid raft-associated transmembrane protein PAG/Cbp. Instead, Csk becomes associated with an similar to72-kDa tyrosine-phosphorylated protein, which we identify here as G3BP, a phosphoprotein reported to bind the SH3 domain of Ras GTPase-activating protein. G3BP reduced the ability of Csk to phosphorylate Lek at Y505 by decreasing the amount of Csk in lipid rafts. As a consequence, G3BP augmented T-cell activation as measured by interleukin-2 gene activation. Conversely, elimination of endogenous G3BP by RNA interference increased Lek Y505 phosphorylation and reduced TCR signaling. In antigen-specific T cells, endogenous G3BP moved into a intracellular location adjacent to the immune synapse, but deeper inside the cell, upon antigen recognition. Csk colocalization with G3BP occurred in this "parasynaptic" location. We conclude that G3BP is a new player in T-cell-antigen receptor signaling and acts to reduce the amount of Csk in the immune synapse. [less ▲]

Detailed reference viewed: 48 (7 ULg)