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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 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 ▲]

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See detailRemoval of dioxins and PCB from fish oil by activated carbon and its influence on the nutritional quality of the oil
Maes, Jeroen; De Meulenaer, B.; Van Heerswynghels, P. et al

in Journal of the American Oil Chemists' Society [=JAOCS] (2005), 82(8), 593-597

Fish oils are well-known sources of nutritionally valuable components such as the n-3 FA EPA and DHA as well as the fat-soluble vitamins A, D, and E. However, some fish oils can be contaminated with ... [more ▼]

Fish oils are well-known sources of nutritionally valuable components such as the n-3 FA EPA and DHA as well as the fat-soluble vitamins A, D, and E. However, some fish oils can be contaminated with considerable amounts of dioxins and dioxin-like PCB. The most important challenge during fish oil refining is to remove these contaminants without altering the levels of nutritionally valuable compounds and the oxidative status and stability of the oil. Treatment with an apolar adsorbent, e.g., activated carbon (AC), seems to be the most efficient process today. Very little information about the adsorption of different dioxin and PCB congeners is available. Four grades of AC were evaluated for their efficiency in removing these compounds. In addition, the effects of the treatment on the nutritional and oxidative quality of the oil were evaluated. After treatment of contaminated cod liver oil [5.4 ppt toxic equivalents (TEQ) polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F), 18.1 ppt TEQ dioxin-like PCB] with 0.5% AC, almost all PCDD/F and up to 80% of the dioxin-like PCB could be removed. AC showed low affinity for mono-ortho PCB (< 30% removal), which could be explained by their noncoplanar structure. Removal efficiencies were dependent on the grade and percentage of AC used. The treatment of contaminated cod liver oil caused no important effects on oil quality or FA composition in the conditions tested. [less ▲]

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See detailRemoval of dioxins and PCBs in fish oils: comparison of CALUX and GC-HRMS results
Carbonnelle, Sophie; Eppe, Gauthier ULg; Hellebosch, Laeticia et al

in Organohalogen Compounds (2005)

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See detailRemoval of dyes from textile wastewater by chemical coagulation
Janezcko, Marta; Gaydardzhiev, Stoyan ULg

in Önal, G. (Ed.) XXIII International Mineral Processing Congress, 3-8 September 2006, Istanbul (2006)

Dye removal mechanisms from textile effluents has been studied by means of surface charge measurempents and image analysis of floc sludge (size, shape, sedimentation properties). Reactive Black 5 and Acid ... [more ▼]

Dye removal mechanisms from textile effluents has been studied by means of surface charge measurempents and image analysis of floc sludge (size, shape, sedimentation properties). Reactive Black 5 and Acid Black 1 commercial dyes have been tested as simulated effluent water solutions treated with synthetic primary coagulants. [less ▲]

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See detailRemoval of PCDD/Fs and DL-PCBs from fish oil by activated carbon: Compliance with European Legislation
Eppe, Gauthier ULg; Carbonnelle, Sophie; Hellebosch, Laeticia et al

in Organohalogen Compounds (2005), 67

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See detailREMOVAL OF PCDD/FS AND DL-PCBS FROM FISH OILS BY VOLATILISATION PROCEDURES
Carbonnelle, Sophie; Eppe, Gauthier ULg; Hellebosch, L. et al

in Organohalogen Compounds (2006)

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See detailRemoval of phosphorous through roasting of oolitic iorn ore with alkaline earth additives
Ionkov, Krassimir ULg; Gaydardzhiev, Stoyan ULg; Bastin, David ULg et al

in Proceedings of the XXVI International Mineral Processing Congress (2012, September)

The present study is devoted to improvement of the leaching efficiency during phosphorous removal from high phosphorous gravity-magnetic concentrate. Before leaching the concentrate has been subjected to ... [more ▼]

The present study is devoted to improvement of the leaching efficiency during phosphorous removal from high phosphorous gravity-magnetic concentrate. Before leaching the concentrate has been subjected to roasting with the addition of either Ca(OH)2 or CaO. The oolitic iron ore is roasted at 900°C for one hour. This reflects in reaction between alkaline earth additive and quartz, aluminosilicates, phosphorus, and some other minor components of the gangue minerals. The application of leaching, physical separation, and wash out of salts has resulted in the decrease of phosphorus from 0.7 to 0.15 % and it is established that the major influencing factor is the concentration of acid and to a less extent duration of the leaching process. About two third of the phosphorus can be removed by roasting with 3 % CaO to hematite, coarse grinding to d50 0.3 mm, dry high intensity magnetic separation and leaching of the magnetic fraction with hydro-chloric or nitric acid. [less ▲]

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See detailRemoval of selected azo dyes from textile wastewater by chemical coagulation/flocculation: implication of the dye destabilization mechanism
Janeczko, M.; Gaydardzhiev, Stoyan ULg; Ay, P.

in Fecko P et al. (Ed.) Proceedings of 10-th Conference on Environment and Mineral Processing (2006, June)

The results of the coagulation/flocculation of six commercially used textile azo dyes coagulated with synthetic primary coagulants are discussed in the paper. Surface charge measurement of coagulated dye ... [more ▼]

The results of the coagulation/flocculation of six commercially used textile azo dyes coagulated with synthetic primary coagulants are discussed in the paper. Surface charge measurement of coagulated dye-flocs was employed to find a correlation between its sign and the level of colour removal. Additionally, flocs characterization was done with the aim to link data with surface charge and on this basis to outline the predominant mechanism of colour removal. Based on the results obtained, the evident correlation between surface charge density progression of coagulated dye flocs and colour removal after different solid/liquid separation methods was observed. Thus, it was concluded that the charge neutralization was the predominant mechanism responsible for dye destabilisation. It was found out also that flocs produced at optimal dosage are characterized by large median size and high value of fractal dimension [less ▲]

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