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See detailMonitoring sanitaire des ongulés sauvages
Linden, Annick ULg

Article for general public (2003)

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See detailMonitoring soil organic carbon in croplands using imaging spectroscopy (moca project)
Stevens, Antoine; van Wesemael, Bas; Tychon, Bernard ULg et al

Conference (2008, February 12)

The detection of changes in soil organic carbon (SOC) concentration is essential in both the assessment of SOC sequestration and soil quality. Within the EU soil thematic strategy the depletion of organic ... [more ▼]

The detection of changes in soil organic carbon (SOC) concentration is essential in both the assessment of SOC sequestration and soil quality. Within the EU soil thematic strategy the depletion of organic matter is mentioned as one of the major threats to the soil resource. As one of the first countries Luxemburg has taken the initiative to monitor the SOC concentration of individual fields to allow for eventual CO2 credits and as an indicator for good agro-ecological conditions (GAEC). The aim of this project is to develop an efficient and operational methodology to detect SOC changes in croplands using Imaging Spectroscopy and to map the SOC contents of croplands with high resolution and minimal calibration. [less ▲]

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See detailMonitoring System For The Biocontrol Agent Pichia Anomala Strain K Using Quantitative Competitive Pcr-Elosa
Pujol, M.; De Clercq, D.; Cognet, S. et al

in Plant Pathology (2004), 53(1), 103-109

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See detailMonitoring temperature changes during heat tracing experiments using electrical resistivity tomography
Hermans, Thomas ULg; Wildemeersch, Samuel ULg; Nguyen, Frédéric ULg

Conference (2013, December 06)

Thermal tracing experiments are becoming common in hydrogeology to estimate parameters governing heat transport processes and to study geothermal reservoirs. Electrical resistivity tomography (ERT) has ... [more ▼]

Thermal tracing experiments are becoming common in hydrogeology to estimate parameters governing heat transport processes and to study geothermal reservoirs. Electrical resistivity tomography (ERT) has proven its ability to monitor salt tracer tests, but few studies have investigated its performances, both qualitatively and quantitatively, in thermal tracing experiments. In this study, we monitored a heat injection and pumping experiment in an alluvial aquifer using both surface and crosshole ERT. The data sets of the surface profile, located along the main direction of flow, are distorted during injection by an electrical short-circuit through the external pumping-heating-injection experimental set-up. Current is flowing outside the subsurface leading to bad data for electrode dipoles located near the pumping and injection wells. The crosshole ERT panel is perpendicular to the main direction of flow. Difference inversion time-lapse images clearly show a preferential flow path in the bottom of the aquifer related to the presence of a coarse and clean gravel layer. Direct temperature measurements are available in control piezometers during the experiment to validate the ERT-derived temperatures and confirm the spatial pattern of temperature observed with ERT. Breakthrough curves are correctly retrieved in time and difference of 10 to 20% are observed for temperature estimation. The latter requires site-specific petrophysical laws and chemical stability assumptions that must be carefully verified. Our study proves that ERT, especially crosshole ERT, is a reliable tool to follow thermal tracing experiments but also to characterize heat transfer in the subsurface and to monitor geothermal resource exploitations. We also show that surface ERT may be impacted by the survey layout in unsuspected ways. [less ▲]

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See detailMonitoring the circadian rhythm of serum and salivary cortisol concentrations in the horse
Bohak, Zs; Szabo, F.; Beckers, Jean-François ULg et al

in Domestic Animal Endocrinology (2013), 45(1), 38-42

Daily fluctuations of cortisol concentration in the blood or saliva have been repeatedly reported. However, several contradictions in the existing literature appear on this subject. The present study was ... [more ▼]

Daily fluctuations of cortisol concentration in the blood or saliva have been repeatedly reported. However, several contradictions in the existing literature appear on this subject. The present study was performed to definitively establish options for testing adrenocortical function. To the best of our knowledge, this is the first study to evaluate parallel circadian rhythms in salivary and serum cortisol concentrations during a 24-h period. Twenty horses were examined under the same conditions. Blood and saliva samples were taken every 2 h for 24 h to determine the daily changes in cortisol concentrations of saliva and serum at rest and to determine the relationship between salivary and serum cortisol levels. Cosinor analysis of group mean data confirmed a significant circadian component for both serum and salivary cortisol concentrations (P < 0.001 in both cases). The serum cortisol circadian rhythm had an acrophase at 10:50 AM (95% CI, 10:00 AM-11:40 AM), a MESOR of 22.67 ng/mL, and an amplitude of 11.93 ng/mL. The salivary cortisol circadian rhythm had an acrophase at 10:00 AM (95% CI, 9:00 AM-11:00 AM), a MESOR of 0.52 ng/mL, and an amplitude of 0.12 ng/mL. We found a significant but weak association between salivary and serum cortisol concentrations; the Pearson correlation coefficient was 0.32 (P < 0.001). The use of salivary cortisol level as an indicator of hypothalamic-pituitary-adrenal axis activity may be warranted. However, the salivary cortisol levels are more likely to be correlated with free plasma cortisol than with the total plasma cortisol concentration. [less ▲]

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See detailMonitoring the dayside and nightside reconnection rates during various auroral event using IMAGE-FUV and SUPERDARN data
Hubert, Benoît ULg; Palmroth, M.; Milan, S. E. et al

in Syrjasuo, M.; Donovan, E. (Eds.) Substorms VIII (2006, March)

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See detailMonitoring the evolution of irrigated areas with Landsat images using backward and forward change detection analysis in the Kou watershed
Traore, Farid ULg; Cornet, Yves ULg; Denis, Antoine ULg et al

in Geocarto International (2013)

The Kou watershed is characterized by important water resources used for drinking, agriculture (especially in the important irrigated areas), industry and the preservation of aquatic fauna and flora. For ... [more ▼]

The Kou watershed is characterized by important water resources used for drinking, agriculture (especially in the important irrigated areas), industry and the preservation of aquatic fauna and flora. For several decades there has been increasing pressure on the Kou’s water resources, partly because of the expansion of the irrigated agricultural areas. This study was conducted to examine this issue, focusing on one specific irrigated area. In order to monitor the expansion of irrigated areas in developing countries, a low-cost remote sensing method based on Landsat images and aerial photographs was developed. The method is based on maximum-likelihood classifications, followed by backward and forward change detection analysis requiring agronomic expertise. Using pixel trajectory analysis, the method connects all pixels to their consecutive states in order to correct their current states. The study showed that the irrigated area has expanded by almost 80% over 20 years, with most of this expansion occurring in the past 10 years. The approach, if validated, could be used to obtain information on past occupation in the rural irrigated areas for which there is no archived data. [less ▲]

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See detailMonitoring the exhaust air of a compost pile as a process variable with an e-nose
Romain, Anne-Claude ULg; Godefroid, D.; Kuske, M. et al

in Sensors and actuators. B, Chemical (2005), 106(1), 29-35

In this paper, the monitoring of the composting process with an e-nose is presented. An emission chamber is developed for this purpose and put on a household waste compost pile. A lab-made e-nose with ... [more ▼]

In this paper, the monitoring of the composting process with an e-nose is presented. An emission chamber is developed for this purpose and put on a household waste compost pile. A lab-made e-nose with metal oxide sensors is located at the exit of this chamber. Simultaneously to the e-nose measurements, air sampling on sorbent tubes as well as physico-chemical analysis are realised. The adsorbed air samples are analysed in the lab by gas chromatography coupled to mass spectrometry (GC-MS). In addition, some parameters of the composting process are collected (compost temperature, age of the pile, date of the aeration). Correlation between the sensors and 14 chemical families is determined by principal component analysis (PCA). By canonical analysis, two models are developed and calibrated by the proportion of each chemical family and in function of the compost process events. Thanks to these models, monitoring of various kinds of compost process events is possible with only one measurement device. © 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailMonitoring the exhaust air of a compost pile with an e-nose and comparison with GC-MS data
Romain, Anne-Claude ULg

Textual, factual or bibliographical database (2006)

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See detailMonitoring the influence of light intensity on the growth and mortality of duckweed (Lemna minor) through digital images processing
Tangou Tabou, Thierry ULg; Baya, Dehenould Trésor; Musibono Eyul'anki, Dieudonné et al

Conference (2013, August)

The growth of duckweed (Lemna minor), depending on biotic and abiotic factors (i.e. temperature, light intensity, photoperiod, pH, nutrients), is an important compartment of the treatment process in ... [more ▼]

The growth of duckweed (Lemna minor), depending on biotic and abiotic factors (i.e. temperature, light intensity, photoperiod, pH, nutrients), is an important compartment of the treatment process in wastewater floating macrophytes ponds. Excess or shortage of this biomass might be responsible of the dysfunction of such ponds. Modeling these duckweed ponds through mass balances based on Petersen’s matrix should help in an optimal management of such facilities. This article focused on (i) the influence of light intensity on the growth, and (ii) the mortality of Lemna minor under a constant temperature. Experiments were carried out in a growth chamber using a pilot consisting of transparent cubic tanks, with an initial fresh Lemna minor biomass. In order to monitor Lemna minor biomass, digital image processing was achieved in addition to fresh weight and dry weight measurements methods. The results showed that Lemna minor reached a maximum growth rate (0.19 d-1) for light intensities ranging between 250 μmol.m-².s-1 and 300 μmol.m-². s-1. Light intensities from 300 μmol.m-².s-1 to 400 μmol.m-².s-1 induced a slight growth inhibition. This inhibition was strongly marked at 450 μmol.m-².s-1. As for mortality, very low levels (< 0.05 d-1) were determined. These results thus provide a contribution in the modeling of duckweed waste stabilization ponds. [less ▲]

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See detailMonitoring the ionospheric activity using GNSS. From dual frequency GPS to multi-constellation multi-frequency GNSS
Warnant, René ULg; Bidaine, Benoît; Lonchay, Matthieu ULg et al

Scientific conference (2012, June 20)

Detailed reference viewed: 48 (1 ULg)
See detailMonitoring the ionospheric positioning error with a GNSS dense network
Wautelet, Gilles ULg; Lejeune, Sandrine; Warnant, René ULg

Conference (2010, May 06)

Detailed reference viewed: 31 (4 ULg)
See detailMonitoring the Ionospheric TEC using GPS Data
Warnant, René ULg; Wanninger, Lambert

in Kersley, Len (Ed.) Proceedings of Beacon Satellite Symposium '94 (1994)

Detailed reference viewed: 7 (0 ULg)
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See detailMonitoring the odour of compost as a process variable
Romain, Anne-Claude ULg; Kuske, M.; Nicolas, Jacques ULg

in Kleperis, janis (Ed.) book of abstracts of the 10th international symposium on olfaction and electronic nose (2003)

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See detailMonitoring the stratospheric chlorine budget during the past decades: the Montreal Protocol at work
Mahieu, Emmanuel ULg; Zander, Rodolphe ULg; Mélen, Francine et al

in NASDA (Ed.) Proceedings of the Quadriennal ozone symposium - Sapporo 2000 (2000)

The study of series of ground-based solar observations performed within the frame of the NDSC indicates that the rate of increase of the atmospheric loading of inorganic chlorine has progressively slowed ... [more ▼]

The study of series of ground-based solar observations performed within the frame of the NDSC indicates that the rate of increase of the atmospheric loading of inorganic chlorine has progressively slowed down, then stabilized around 1996-97, with a subsequent tendency towards a decrease. The investigation is based on total column abundances of HCl and ClONO2 measured at the Jungfraujoch station in the Swiss Alps and on stratospheric columns of HCl derived from observations at Kitt Peak National Observatory (Arizona, USA). The observed changes are compared with near-global observations of HCl around the stratopause by HALOE and with a global, best-case emission scenario of Cl-bearing ground-level source gases compiled by UNEP [less ▲]

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See detailMonitoring the zinc affinity of the metallo-beta-lactamase CphA by automated nanoESI-MS
De Vriendt, K.; Van Driessche, G.; Devreese, B. et al

in Journal of the American Society for Mass Spectrometry (2006), 17(2), 180-188

Metallo-beta-lactamases are zinc containing enzymes that are able to hydrolyze and inactivate beta-lactam antibiotics. The subclass B2 enzyme CphA of Aeromonas hydrophila is a unique metallo-p-lactamase ... [more ▼]

Metallo-beta-lactamases are zinc containing enzymes that are able to hydrolyze and inactivate beta-lactam antibiotics. The subclass B2 enzyme CphA of Aeromonas hydrophila is a unique metallo-p-lactamase because it degrades only carbapenems efficiently and is only active when it has one zinc ion bound. A zinc titration experiment was used to study the zinc affinity of the wild-type and of several mutant CphA enzymes. It shows that a second Zn2+ is also bound at high ion concentrations. All samples were analyzed using mass spectrometry in combination with an automated nanoESI source. The metal-free enzyme has a bimodal charge distribution indicative of two conformational states. A completely folded enzyme is detected when the apo-enzyme has bound the first zinc. Intensity ratios of the different enzyme forms were used to deduce the zinc affinities. CphA enzymes mutated in metal ligands show decreased zinc affinity compared to wild-type, especially D120 mutants. [less ▲]

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See detailLe monitoring thérapeutique des antidépresseurs
Charlier, Corinne ULg; Ansseau, Marc ULg; Gougnard, Thierry et al

in Revue Médicale de Liège (1997), 52(5), 336-44

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See detailMonitoring, tracking and forecasting ionospheric perturbations using GNSS techniques
Jakowski, Norbert; Béniguel, Yannick; De Franceschi, Giorgiana et al

in Journal of Space Weather and Space Climate (2012), 2(A22),

The paper reviews the current state of GNSS-based detection, monitoring and forecasting of ionospheric perturbations in Europe in relation to the COST action ES0803 ‘‘Developing Space Weather Products and ... [more ▼]

The paper reviews the current state of GNSS-based detection, monitoring and forecasting of ionospheric perturbations in Europe in relation to the COST action ES0803 ‘‘Developing Space Weather Products and Services in Europe’’. Space weather research and related ionospheric studies require broad international collaboration in sharing databases, developing analysis software and models and providing services. Reviewed is the European GNSS data basis including ionospheric services providing derived data products such as the Total Electron Content (TEC) and radio scintillation indices. Fundamental ionospheric perturbation phenomena covering quite different scales in time and space are discussed in the light of recent achievements in GNSS-based ionospheric monitoring. Thus, large-scale perturbation processes characterized by moving ionization fronts, wave-like travelling ionospheric disturbances and finally small-scale irregularities causing radio scintillations are considered. Whereas ground and space-based GNSS monitoring techniques are well developed, forecasting of ionospheric perturbations needs much more work to become attractive for users who might be interested in condensed information on the perturbation degree of the ionosphere by robust indices. Finally, we have briefly presented a few samples illustrating the space weather impact on GNSS applications thus encouraging the scientific community to enhance space weather research in upcoming years. [less ▲]

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See detailEl monje y la hija del verdugo
Bierce, Ambrose; Willson, Patricia ULg

Book published by Libros del Zorro Rojo (2011)

Detailed reference viewed: 20 (3 ULg)