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See detailQuantification and monitoring of contaminant mass fluxes in heterogeneous subsurface media
Jamin, Pierre ULg; Brouyère, Serge ULg

Poster (2011, May 26)

Since the beginning of the years 2000, a consensus has been growing among the scientific, technical and decision makers community concerning the fact that the characterisation and the management of ... [more ▼]

Since the beginning of the years 2000, a consensus has been growing among the scientific, technical and decision makers community concerning the fact that the characterisation and the management of contaminated sites have to be performed in terms of contaminant flux metrics instead of to be based on a simplistic study of pollutant concentration coming from piezometers randomly spread over the site. Contaminant plumes and associated pollutant mass fluxes are extremely variable in space as well as in time. The scientific and technical challenge is to capture this double heterogeneity in order to consider it explicitly or statistically for the management of a contamination issue. This requires (1) the interception of the entire contaminated groundwater flowing section with a control panel; (2) the ability to measure and to calculate accurately groundwater and contaminant fluxes across that panel; and (3) the repetition of the measurement to bring out the spatial and the temporal variation of contaminant fluxes. This research project aims to develop an integrated pollutant flux measurement approach for contaminated groundwater at the scale of the contaminant plume. This approach lays on a triple integration of (1) single well tracing techniques – (2) passive sampling – (3) control panel. Spatial and temporal variability of groundwater fluxes will be quantified by the point dilution tracing method derived from the “FVPDM” technique (Brouyère et al. 2008). In the same time, the amount of pollutant flowing through the same location will be determined by the adequate passive sampling technique (PS). The integration of these two measures in an interpretation schema based on mathematical and numerical modelling will allow quantifying contaminant fluxes and their variability over time. The adaptation at the scale of the contaminant plume will be based on a logging-type use of techniques, repeated along the vertical axis of the monitoring wells and repeated from one well to an other of a control panel implanted to intercept the plume. All the research results and developed techniques will then be integrated into a complete measurement system (PS-FVPDM), mobile and easily usable on field. The whole development and testing will take place on several pilot contaminated test site located in various hydrogeological context. [less ▲]

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See detailQuantification by PIXE of metallic sites in proteins separated by electrophoresis
Strivay, David ULg; Schoefs, B.; Weber, Georges ULg

in Nuclear Instruments & Methods in Physics Research Section B (1998), 137

Electrophoresis on polyacrylamide gel (PAGE) is widely used in life sciences to determine the molecular weight of proteins in solution by separating them into different bands. By coupling electrophoresis ... [more ▼]

Electrophoresis on polyacrylamide gel (PAGE) is widely used in life sciences to determine the molecular weight of proteins in solution by separating them into different bands. By coupling electrophoresis and Particle Induced W-ray Emission (PIXE), the nature and the quantity of metals contained in proteins can be investigated. After the electrophoresis, the gel is dried and each track is scanned with a 2.5 MeV proton beam which induces X-ray emission. Analysis of these spectra allows the determination of the metals contained in an electrophoretic band. The metal content in each band is obtained by comparing the characteristic X-ray peak area with those obtained with polyacrylamide gels doped with the same metal. Finally, the relative concentration of each protein is determined by densitometry in order to compute the protein/metal ratio. An example of metallic site determination is presented. This procedure seems to be a very useful multielementary method for the determination of the metal amounts inside proteins after their separation by electrophoresis. Furthermore it allows to check if metals remain bound to proteins. (C) 1998 Elsevier Science B.V. [less ▲]

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See detailQuantification de la robustesse du procédé de thixoformage des aciers
Pierret, Jean-Christophe ULg

Doctoral thesis (2009)

This work aims to assess the robustness of the steel thixoforming process by a qualitative and quantitative study of the influence of the parameters involved in the process. Thixoforming is the shaping of ... [more ▼]

This work aims to assess the robustness of the steel thixoforming process by a qualitative and quantitative study of the influence of the parameters involved in the process. Thixoforming is the shaping of metals in the semi-solid state and with a globular microstructure. In this case, one shows that consistency decreases when shear rate increases and that the process parameters leading the behaviour are time dependent. As a key-step of the technology, heating is studied as well as forming. Influences of heating strategy, inductor’s geometry and external conditions are determined by the help of modelling and heating experiments. Handling system between heating furnace and press is also tackled. To study the forming’s relability and sensitivity, three geometries are used : direct extrusion, a rheological study part and an industrial part. Again, practical experiments and modelling are used in a complementary way. Effects of slug’s temperature, forming speed, lubrication and tool’s temperature are analysed. Repeatability of heating and forming are highlighted. The defects and structures obtained in the parts are presented before discussing the thixoformability of steel grades. In particular, qualification of especially designed grades as well as non adapted grades is discussed. Finally, the tooling wear and lifetime issues are detailed as it is one of the mean locks of the technology industrialisation. [less ▲]

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See detailQuantification des politiques versus démocratisation de l’évaluation : Etude des plans de cohésion sociale en Wallonie
Fallon, Catherine ULg; Feron, Pauline

in Mespoulet, Martine (Ed.) Usages des chiffres dans l’action publique territoriale (in press)

L’usage des chiffres dans l’action publique (ou la « quantification du politique ») mobilise deux registres en tension : premièrement celui de la performance, où « le chiffre est conçu comme un acteur ... [more ▼]

L’usage des chiffres dans l’action publique (ou la « quantification du politique ») mobilise deux registres en tension : premièrement celui de la performance, où « le chiffre est conçu comme un acteur contribuant à encadrer l’action en restreignant les options soumises à délibération et les choix ouverts à la décision collective », et deuxièmement la démocratie, perçue comme « un facteur d’extension du débat public et d’accroissement des sphères d’exercice de la responsabilité politique des citoyens ». Ogien relève le renforcement de cette tension, tout en soulignant l’absence de démocratisation de la mesure elle-même. Afin de remédier à cet écueil, l’auteur propose que les citoyens, rarement pris en considération dans l’élaboration et la définition des termes de la mesure, soient parties prenantes « du système du chiffre qui sert à rendre compte de leur existence et de leur destinée ». Cette contribution analyse les modalités concrètes de cette tension dans le cadre de l’évaluation d’une politique régionale mise en place au niveau local, les plans de cohésion sociale (PCS) en Région wallonne (Belgique), en mobilisant les données recueillies lors de l’évaluation des PCS terminée en mars 2013 . En effet, un enjeu important des PCS était la mise en place d’un processus d’évaluation qui se voulait « participatif» . La participation citoyenne étant une notion centrale de la philosophie PCS, un des objectifs de la Direction interdépartementale de la cohésion sociale (DiCS – administration régionale en charge du programme) était de la promouvoir à travers toutes les étapes de mise en œuvre de cette politique, y compris pour l’évaluation d’impact, inspirée en cela par les propositions méthodologiques du Conseil de l’Europe. Dans un premier temps, le bureau régional de statistique avait développé un indicateur composite « d’accès aux droits sociaux fondamentaux » afin d’objectiver la clé de répartition des ressources entre les territoires locaux. Ce n’est que dans un second temps, en fin de programme, que la DiCS était sommée de produire une « évaluation participative » mesurant l’impact des actions réalisées à travers les PCS sur la cohésion sociale et le bien-être. L’article propose de confronter ces deux démarches d’évaluation : celle qui aboutit à un indicateur quantitatif fondé sur une logique statistique et l’approche participative favorisant l’expression des parties prenantes. [less ▲]

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See detailQuantification et analyse évolutive de la désurbanisation
Halleux, Jean-Marie ULg; Lambotte, Jean-Marc ULg

in De Keersmaecker, M.-L. (Ed.) Les coûts de la désurbanisation (2002)

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See detailQuantification in postmortem blood and identification in urine of tramadol and its two main metabolites in two cases of lethal tramadol intoxication
De Backer, Benjamin ULg; Renardy, Françoise ULg; Denooz, Raphaël ULg et al

in Journal of Analytical Toxicology (2010), 34(9), 599-604

Tramadol has been extensively prescribed for two decades. It is an opioid analgesic considered to induce fewer side effects than other compounds of this class. However, serious complications may occur in ... [more ▼]

Tramadol has been extensively prescribed for two decades. It is an opioid analgesic considered to induce fewer side effects than other compounds of this class. However, serious complications may occur in case of intoxication. We report here two cases of fatal intoxication due to tramadol ingestion. Tramadol, O-desmethyltramadol (ODT) and N-desmethyltramadol (NDT) were quantitatively and qualitatively determined in postmortem blood and urine, respectively. An HPLC method coupled with fluorescence detection was validated using total error approach for the analysis of tramadol, ODT, and NDT in blood. In case1, concentrations of tramadol and its metabolites were 7.7 mg/L (tramadol), 1.33 mg/L (ODT), and 0.6mg/L (NDT). In case 2, concentrations found were 48.34 mg/L (tramadol), 2.43 mg/L (ODT), and 10.09 mg/L (NDT). Opposite ratios of ODT/NDT concentrations observed in different cases were suggested to be useful for the evaluation of the delay between ingestion and death. However, the changes in metabolites levels may also be explained by pharmacokinetic interactions and quantitative differences in the activity of the cytochrome-P450 2D6. Interestingly, norfluoxetine was detected in sub-therapeutic levels in case 2. Most of these aspects in tramadol-related fatalities are reviewed in this paper, and an overview of fatal intoxications due to tramadol is presented. [less ▲]

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See detailQuantification in postmortem blood and identification in urine of tramadol and its two main metabolites in two cases of lethal tramadol intoxication
De Backer, Benjamin ULg; Renardy, Françoise ULg; Denooz, Raphael ULg et al

in Mitteilungsblatt der Gesellschaft für Toxikologische und Forensische Chemie (2010), 77(3), 252

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See detailQuantification of Acrylamide in Various Belgian Potato Products Using Solid Phase Extraction and Liquid Chromatography Tandem Mass Spectrometry Detection
Douny, Caroline ULg; Widart, Joëlle ULg; Maghuin-Rogister, Guy ULg et al

in Food and Public Health (2012), 2(5), 137-141

Acrylamide (CH2=CHCONH2), a neurotoxic and potentially carcinogenic substance for human health, is in the glare of the spotlights for a few years. This is mostly due to the fact that acrylamide was found ... [more ▼]

Acrylamide (CH2=CHCONH2), a neurotoxic and potentially carcinogenic substance for human health, is in the glare of the spotlights for a few years. This is mostly due to the fact that acrylamide was found worldwide in various heated foodstuffs. Levels reported in the literature vary from 25 to 2000 ìg/kg and potato products are considered as the most contaminated. A possible pathway of synthesis of acrylamide is the Maillard reaction between reducing sugars and the amino acid asparagine. The aim of this study was to develop a liquid chromatography/mass spectrometry method to analyse as quickly as possible acrylamide in a variety of Belgian food samples such as potatoes, French fries, crisp bread, coffee, corn-flakes, etc. The sample preparation consisted in a liquid/liquid extraction, a centrifugation, followed by purification with Solid Phase Extraction (SPE). The instruments used were a Waters 2690 Alliance HPLC system coupled to a Micro-mass Quattro Ultima Platinum triple-quadrupole mass spectrometer. The analysis was performed in MS/MS mode using isotopic dilution technique for quantification. An internal 13C3 labelled standard was added prior to extraction. Quantifica-tion in MS/MS mode was calculated by reconstructing the ion current with the most abundant daughter ions for native and 13C labelled standard (ions of m/z 55 and 58). [less ▲]

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See detailQuantification of Angiogenesis of Embryonic Implantation Site by Image Analysis
Le Maire, Sophie; Blacher, Silvia ULg; Frankenne, F. et al

Conference (2003)

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See detailQuantification of angiogenesis on the rat aortic ring assay.
Blacher, Silvia ULg; Devy, L.; Noël, Agnès ULg et al

in Image Analysis and Stereology (2003), 22

Image analysis is used to quantify angiogenesis on the rat aortic ring model. This technique allows to determine: (1) the aortic ring area and factor shape; (2) the number of microvessels, the total ... [more ▼]

Image analysis is used to quantify angiogenesis on the rat aortic ring model. This technique allows to determine: (1) the aortic ring area and factor shape; (2) the number of microvessels, the total number of branching, the maximal microvessel length and the number of microvessels in function of the distance to the aortic ring; (3) the total number of isolated fibroblast-like cells and the number of fibroblast-like cells in function of the distance to the aortic ring. We show that this method is suitable to quantify spontaneous angiogenesis as well as to analyse a complex microvascular network induced by vascular endothelial growth factor (VEGF). [less ▲]

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See detailQuantification of aporphines in cassytha filiformis bu HPLC/UV : validation and application
Stevigny, C.; Wautier, M. C.; Chiap, Patrice ULg et al

Poster (2004)

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See detailQuantification of Bifidobacterium spp. and Lactobacillus spp. in rat fecal samples by real-time PCR.
Delroisse, Jean-Marc; Boulvin, Anne-Lise; Parmentier, Isabelle et al

in Microbiological research (2006), (5),

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See detailQuantification of Bifidobacterium ssp and Lactobacillus spp in rat fecal samples by real-time PCR
Delroisse, Jean-Marc; Boulvin, Anne-Lise; Parmentier, Isabelle et al

in Archives Internationales de Physiologie et de Biochimie (2005), 191

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See detailQuantification of bST in milk by electrochemiluminescence: a way for detection of treated cows.
Renaville, Robert ULg; Deaver, D.; Baronheid, Christophe et al

in Proceedings of the 4th International Conference on Farm Animal Endocrinology (2001, October)

Detailed reference viewed: 14 (0 ULg)