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See detailBiometry and paleoenvironment of Retispora lepidophyta (Kedo) Playford 1976 and associated miospores in the latest Famennian nearshore marine facies, eastern Ardenne (Belgium)
Maziane, N.; Higgs, K. T.; Streel, Maurice ULg

in Review of Palaeobotany and Palynology (2002), 118(1-avr Sp. Iss. SI), 211-226

The size diameter of Retispora lepidophyta, a stratigraphically important miospore, is reexamined in greater detail than in previous studies using three sections of the latest Famennian nearshore marine ... [more ▼]

The size diameter of Retispora lepidophyta, a stratigraphically important miospore, is reexamined in greater detail than in previous studies using three sections of the latest Famennian nearshore marine facies of the eastern Ardenne. The evolutionary character of the size reduction with time is confirmed and is used for accurate correlations between the three sections. Cluster analyses (dendrograms) are performed on the percentages of a selection of miospore species from the two most complete sections and show a clear analogy in the lateral distribution of R. lepidophyta and Vallatisporites hystricosus, a species known elsewhere (West Virginia, USA) to belong to coastal 'downstream' near-swamp plant communities [Streel and Scheckler, Rev. Palaeobot. Palynol. 64 (1990) 315-324]. By comparison also with the West Virginia data, three Diducites species are believed to represent the 'coal' swamp vegetation. A decrease in the proportion of the Diducites species from the lower to the upper portion of the studied sections is observed. Using biometric analysis, high resolution correlation between these sections reveals a lateral shift of facies with time during the latest Famennian in the eastern Ardenne. Local synsedimentary block-faulting processes were probably responsible. (C) 2002 Elsevier Science B.V. All rights reserved. [less ▲]

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See detailEtude electromyographique paravertebrale dorso-lombaire. Analyse en mode multi-MUP et etablissement de normes au sein d'une population de reference
Tomasella, Marco ULg; Crielaard, Jean-Michel ULg; WANG, François-Charles ULg

in Neurophysiologie Clinique = Clinical Neurophysiology (2002), 32(2), 109-17

OBJECTIVE: The aim of this study was to contribute to draw up reference values relating to electromyographic (EMG) parameters in dorsal and lumbar paraspinal muscles. MATERIALS AND METHODS: 75 healthy ... [more ▼]

OBJECTIVE: The aim of this study was to contribute to draw up reference values relating to electromyographic (EMG) parameters in dorsal and lumbar paraspinal muscles. MATERIALS AND METHODS: 75 healthy subjects without back pain underwent electromyography of multifidus bundles, which are innervated uni-segmentally by the dorsal ram of the spinal nerve. T8, L3, L4, L5 and S1 myotomes were systematically explored. Output variables were spontaneous denervation activity and quantitative EMG data obtained by multi-MUP (Motor Unit action Potential) analysis. RESULTS: No abnormal insertional or spontaneous activity (such as fibrillation, positive sharp waves or fasciculation) was recorded at rest. Neither sex nor age influenced motor unit action potential features in our series. Reference values were drawn up for T8 and L5 segmental levels using the mean values of 20 motor unit potentials in each patient studied, the reference interval being defined by the lower and the upper outlier limits on individual values. CONCLUSION: This study offers reference data to electromyographers to help better identifying possible myogenic or neurogenic pathological changes, especially in lumbosacral radiculopathies. [less ▲]

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See detailDetermination of the singlet oxygen quantum yield of bacteriochlorin a: a comparative study in phosphate buffer and aqueous dispersion of dimiristoyl-L-a-phosphatidylcholine liposomes
Hoebeke, Maryse ULg; Damoiseau, Xavier

in Photochemical & Photobiological Sciences (2002), 1(4), 283-287

The production of singlet oxygen (1O2) by bacteriochlorin a (BCA) was studied in phosphate buffer and in dimyristoyl-L-α-phosphatidylcholine (DMPC) unilamellar liposomes. The comparative method used to ... [more ▼]

The production of singlet oxygen (1O2) by bacteriochlorin a (BCA) was studied in phosphate buffer and in dimyristoyl-L-α-phosphatidylcholine (DMPC) unilamellar liposomes. The comparative method used to measure 1O2 production was a quantitative analysis of photooxidation reactions leading to the loss of absorbance of the water-soluble specific probe: anthracene 9,10-dipropionic acid. Rose Bengal, whose 1O2 quantum yield (ΦRB) is well known in alcohols and phosphate buffer, was used as the standard for the quantification of the BCA singlet oxygen production. Our results confirm quantitatively that solubilization of BCA in liposomes leads to an increase in 1O2 production. Indeed, the quantum yield of 1O2 production by BCA (ΦBCA) is 0.05 in phosphate buffer and 0.33 in DMPC liposomes. Furthermore, the diffusion characteristics of 1O2 produced by BCA bound to liposome were also examined using the isotopic lifetime enhancement effect of D2O. It was shown that 1O2 spent at least 70% of its lifetime in the vesicular environment [less ▲]

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See detailFull-scale tests of torsional damper and detuner (TDD) antigalloping device
Lilien, Jean-Louis ULg; Vinogradov, Alexander

in IEEE Transactions on Power Delivery (2002), 17(2), 638-643

A new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed ... [more ▼]

A new antigalloping device for overhead lines with bundle conductors was introduced ten years ago, after laboratory tests and observations on actual 400-kV lines. A systematic fullscale test was performed in Kazakhstan in order to better evaluate torsional damper and detuner (TDD) efficiency. This report details the test station and the results obtained over a several month period of testing and measurement. The tests were carried out thanks to the mutual efforts of the ESSP and the Kazakh Power Research Institute (KazNIIE) at the field tests stand located in Chokpar. [less ▲]

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See detailA real-time operational procedure for GPS TEC based reconstruction of the electron profile at a single ionosonde location
Stankov, Stanimir; Warnant, René ULg; Jodogne, Jean-Claude

in Geophysical Research Abstracts (2002, April), 4(ABS No. EGS02-A-05554),

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See detailClinique et cytologie sputaire de l'asthme intrinseque
Bettiol, J.; Radermecker, Maurice ULg; Louis, Renaud ULg

in Revue Médicale de Liège (2002), 57(4), 223-7

The diagnosis of intrinsic asthma is evoked in patients with clinical criteria of asthma but, who contrarily to atopic asthmatics, lack history of allergy, specific IgE and skin positive reaction towards ... [more ▼]

The diagnosis of intrinsic asthma is evoked in patients with clinical criteria of asthma but, who contrarily to atopic asthmatics, lack history of allergy, specific IgE and skin positive reaction towards common aeroallergens of the environment. While the bronchial cytology of these two types of asthma is comparable, the immunological mechanisms of intrinsic asthma remain poorly understood because the factors responsible for the bronchial inflammation are unknown. Intrinsic asthma normally begins in adulthood and carries often a more severe prognosis. This disease is more frequent in women and is often associated to nasal polyposis and/or aspirin hypersensitivity. In this work, we have retrospectively studied the demographic and clinical characteristics, as well as the lung function and the sputum cell counts of intrinsic asthmatic outpatients seen during the period of 1996 to 1998 in the Pneumology Department of the CHU Sart Tilman. [less ▲]

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See detailLa cardiologie preventive: strategies chez l'enfant
Massin, M.; Vandoorne, Chantal ULg; Coremans, C. et al

in Revue Médicale de Liège (2002), 57(4), 207-12

The importance of preventive cardiology in youth has been established by several critical observations: there is evidence that the atherogenic process begins in childhood, and that the degree of ... [more ▼]

The importance of preventive cardiology in youth has been established by several critical observations: there is evidence that the atherogenic process begins in childhood, and that the degree of atherogenesis is related to measurable risk factors present during childhood. The literature indicated that long-range prevention of atheroselerosis and its sequelae by control of those risk factors should begin in childhood. This article reviews the established risk factors, the identification of high-risk individuals, public health strategies for the promotion of health in the French Community of Belgium and treatment of high-risk individuals. [less ▲]

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See detailEvaluation of thermodynamic properties of concrete substrates and cement slurries modified with admixtures
Courard, Luc ULg

in Materials and Structures (2002), 35(247), 149-155

The study of the creation and the stability of the interface between concrete substrates and repair systems needs the knowledge of the thermodynamic properties of materials. The measurement of the surface ... [more ▼]

The study of the creation and the stability of the interface between concrete substrates and repair systems needs the knowledge of the thermodynamic properties of materials. The measurement of the surface free energies of liquids is realised by means of Wilhelmy plate method on reference liquid and repair products. In order to determine polar and dispersive components, it is necessary to measure the contact angle of these liquids and products on reference solid surfaces and on concrete, mortars and aggregates. Centrifuged solutions of repair product systems elements were prepared in order to measure surface free energies on pure liquids without solid particles in suspension. Evolution of properties versus time were also taken into account and analysed in comparison with well-known liquids and products. [less ▲]

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See detailQualité de la prise en charge de l'hypertension artérielle. Pouvons-nous, devons-nous faire mieux?
Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2002), 57(4), 202-206

Hypertension is well controlled in only less than 30% of the patients treated by drugs. It is thus important to improve this situation first by checking the treatment compliance but also by trying to ... [more ▼]

Hypertension is well controlled in only less than 30% of the patients treated by drugs. It is thus important to improve this situation first by checking the treatment compliance but also by trying to better educate the hypertensive population about the risk of uncontrolled hypertension and how to decrease this risk. [less ▲]

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See detailPolyethylene-layered silicate nanocomposites prepared by the polymerization-filling technique: synthesis and mechanical properties
Alexandre, Michaël ULg; Dubois, Philippe ULg; Sun, Tao et al

in Polymer (2002), 43(8), 2123-2132

Polyethylene-layered silicate nanocomposites were prepared by the in situ intercalative polymerization of ethylene by the so-called polymerization-filling technique and analyzed by transmission electron ... [more ▼]

Polyethylene-layered silicate nanocomposites were prepared by the in situ intercalative polymerization of ethylene by the so-called polymerization-filling technique and analyzed by transmission electron microscopy (TEM), X-ray diffraction analysis (XRD), differential scanning calorimetry, dynamic mechanical analysis and tensile testing. Non-modified montmorillonite and hectorite were first treated by trimethylaluminum-depleted methylaluminoxane before being contacted by a Ti-based constrained geometry catalyst. The nanocomposite was formed by addition and polymerization of ethylene. In the absence of a chain transfer agent, ultra high molecular weight polyethylene was produced. The tensile properties of these nanocomposites were poor and essentially independent of the nature and content of the silicate. Upon hydrogen addition, the molecular weight of the polyethylene was decreased with parallel improvement of the tensile and shear moduli, in relation to the filler content. The exfoliation of the layered silicates was confirmed by XRD analysis and TEM observation. The mechanical kneading of the molten nanocomposites resulted in the partial collapse of the exfoliated structure driven by the thermodynamic stability of the layered filler. [less ▲]

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See detailL'EAD au service d'une approche centrée sur l'apprenant et sur la médiatisation de l'expérience
Georges, François ULg; Demily, Fabian; Leclercq, Dieudonné ULg et al

(2002, April)

Le Laboratoire de Soutien à l’Enseignement Télématique (LabSET, directrice : M. Poumay) a, entre autres, pour mission d’aider les enseignants et les formateurs à concevoir et à développer leurs cours et ... [more ▼]

Le Laboratoire de Soutien à l’Enseignement Télématique (LabSET, directrice : M. Poumay) a, entre autres, pour mission d’aider les enseignants et les formateurs à concevoir et à développer leurs cours et activités sur Internet. Nous travaillons non seulement avec des institutions d’enseignement supérieur (Université et Hautes Ecoles), mais aussi avec des centres de formation, des centres de compétences, des organismes d’insertion socio-professionnelle et des fédérations d’entreprises. Ces partenariats ont dernièrement fait l’objet de deux projets : Technifutur, du nom de son commanditaire, et FORMADIS subsidié par la Communauté Européenne, le Ministère de l’emploi et de la formation de la région wallonne et le Ministère de l’enseignement supérieur de la Communauté Française de Belgique. L'article décrit ces initiatives. [less ▲]

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See detailComparison of different impulse response measurement techniques
Stan, Guy-Bart; Embrechts, Jean-Jacques ULg; Archambeau, Dominique

in Journal of the Audio Engineering Society (2002), 50(4), 249-262

The impulse response of an acoustical space or transducer is one of its most important characterizations. In order to perform the measurement of their impulse responses, four of the most suitable methods ... [more ▼]

The impulse response of an acoustical space or transducer is one of its most important characterizations. In order to perform the measurement of their impulse responses, four of the most suitable methods are compared: MLS (maximum-length sequence), IRS (inverse repeated sequence), time-stretched pulses, and SineSweep. These methods have already been described in the literature. Nevertheless, the choice of one of them depending on the measurement conditions is critical. Therefore an extensive comparison has been realized. This comparison was done through the implementation and realization of a complete, fast, reliable, and cheap measurement system. Finally, a conclusion for the use of each method according to the principal measurement conditions is presented. It is shown that in the presence of nonwhite noise, the MLS and IRS techniques seem to be more accurate. On the contrary, in quiet environments the logarithmic SineSweep method seems to be the most appropriate. [less ▲]

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See detailLes logiques participatives dans le cadre du parcours d'insertion
Jacquemain, Marc ULg; Carpentier, Dominique

Conference (2002, April)

Le document décrit une intervention sociologique de près de deux années visant à mettre sur pied un dispositif participatif dans le cadre du "parcours d'insertion" des chômeurs en formation. Il s ... [more ▼]

Le document décrit une intervention sociologique de près de deux années visant à mettre sur pied un dispositif participatif dans le cadre du "parcours d'insertion" des chômeurs en formation. Il s'interroge sur les fondements normatifs d'un tel dispositif, mais aussi sur les conditions pratiques de sa réalisation. Il décrit les résultats obtenus et débouche sur la question fondamentale à poser dans le cadre de la participation des citoyens les plus fragiles : ouverture démocratique ou manipulation ? La réponse proposée se trouve évidemment entre ces deux pôles. [less ▲]

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See detailModulation of adipose tissue expression of murine matrix metalloproteinases and their tissue inhibitors with obesity
Maquoi, Erik ULg; Munaut, Carine ULg; Colige, Alain ULg et al

in Diabetes (2002), 51(4), 1093-1101

The potential role of the matrix metalloproteinase (MMP) system in the pathophysiology of the adipose tissue was investigated in a mouse model of nutritionally induced obesity. mRNA levels of 16 MMPs and ... [more ▼]

The potential role of the matrix metalloproteinase (MMP) system in the pathophysiology of the adipose tissue was investigated in a mouse model of nutritionally induced obesity. mRNA levels of 16 MMPs and 4 tissue inhibitors of MMPs (TIMPs) were measured by semiquantitative RT-PCR in adipose tissue isolated from mice maintained for 15 weeks on a standard or high-fat diet. In mice on standard diet, with the exception of MMP-8, all MMP and TIMP transcripts were detected in both gonadal and subcutaneous depots. In obese mice, the expression of MMP-3, -11, -12, -13, and -14 and TIMP-1 mRNAs was upregulated, whereas that of MMP-7, -9, -16, and -24 and TIMP-4 was downregulated. Most MMP and TIMP mRNAs were expressed at higher levels in stromal-vascular cells than in mature adipocytes. Analysis of adipose tissue by in situ fluorescent zymography revealed MMP-dependent proteolytic activities, demonstrating the presence of active MMPs in the intact tissue. In vitro conversion of adipogenic 3T3-F442A cells into mature adipocytes was associated with substantial modulations of MMP and TIMP expression. Moreover, this in vitro adipogenesis was reduced in the presence of a synthetic MMP inhibitor. Thus, the adipose tissue expresses a large array of MMPs and TIMPs, which modulate adipocyte differentiation. [less ▲]

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See detailEtude expérimentale des sons auto-entretenus d’un jet plan impactant sur une fente dans un milieu non confiné
Billon, Alexis ULg; Sakout, Anas; Valeau, Vincent

Conference (2002, April)

Cette étude expérimentale s’intéresse aux sons auto-entretenus générés par un écoulement non confiné : un jet turbulent à grand rapport d’aspect impactant sur une plaque munie d’une fente biseautée. Les ... [more ▼]

Cette étude expérimentale s’intéresse aux sons auto-entretenus générés par un écoulement non confiné : un jet turbulent à grand rapport d’aspect impactant sur une plaque munie d’une fente biseautée. Les éléments caractéristiques des sons auto-entretenus sont mis en avant. L’influence de la distance entre la plaque et la bouche du jet, ainsi que celle de la vitesse du jet ont été étudiées. La fréquence des sons mesurés est comparée aux fréquences propres longitudinales du système et à la fréquence la plus instable de la couche de cisaillement du jet, calculée à l’aide de la théorie de la stabilité linéaire. [less ▲]

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See detailMain concepts of the "European approach" to karst-groundwater-vulnerability assessment and mapping
Daly, Donald; Dassargues, Alain ULg; Drew, David et al

in Hydrogeology Journal (2002), 10(2), 340-345

In order to achieve some consistency in the establishment of groundwater intrinsic vulnerability maps in Europe. a new, approach is proposed by Working Group 1 of the European COST Action 620 on ... [more ▼]

In order to achieve some consistency in the establishment of groundwater intrinsic vulnerability maps in Europe. a new, approach is proposed by Working Group 1 of the European COST Action 620 on "Vulnerability mapping for the protection of carbonate (karst) aquifers". A general procedure is offered which provides consistency while allowing the required flexibility for application to a continent and under conditions of varying geology, scale, information availability, time, and resources. The proposed methodology is designed to be clearly more physically based than the existing vulnerability-mapping techniques. It takes the specificity of the karstic environments into account without necessarily excluding the applicability to other geological conditions. Combined "core factors" for overlying layers and for concentration of flow, account for the relative protection of groundwater from contamination while taking into account any bypass of the overlying layers. A precipitation factor is distinguished for describing: characteristics of the input of water to the system. Differentiation is made between groundwater resource intrinsic vulnerability Mapping and Source intrinsic vulnerability mapping. For the latter, a factor describing the karst network development is relevant. This short technical note describes a first stop in the work program of Working Group 1 of the COST Action 620. Future steps are now in progress to quantify the approach and to apply it in various European pilot areas. [less ▲]

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See detailAlgorithms for openings of binary and label images with rectangular structuring elements
Van Droogenbroeck, Marc ULg

in Talbot, Hugues; Beare, Richard (Eds.) International Symposium on Mathematical morphology (ISMM) (2002, April)

Two new families of algorithms for computing openings of binary and label images are presented in this paper. The first family of algorithms is based on an horizontal scan, and a vertical scan that takes ... [more ▼]

Two new families of algorithms for computing openings of binary and label images are presented in this paper. The first family of algorithms is based on an horizontal scan, and a vertical scan that takes the result of the horizontal scan as input. With the results of these two scans it is possible to compute an opening with respect to a rectangle of any size. The second family of algorithms is based on the construction of an exhaustive list of rectangles included in an object. Rectangles of this list all have a maximal extension, i.e. no larger rectangle included in a region contains them. The opening then results from filling the output image with rectangles larger than the structuring element. After a description of the algorithms we provide a comparison of several algorithms in terms of computation time efficiency. The comparison shows that some of the new algorithms advantageously compete with existing algorithms. [less ▲]

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See detailPurificacao, caracterizacao e dosagem radioimunologica de glicoproteinas associadas a gestacao em zebuinos
Melo de Sousa, Noelita ULg

Doctoral thesis (2002)

The pregnancy-associated glycoproteins (PAGs) constitute a large family of aspartic proteinases expressed in the outer epithelial cell layer of the Artyodactyla placenta. In the first part of the present ... [more ▼]

The pregnancy-associated glycoproteins (PAGs) constitute a large family of aspartic proteinases expressed in the outer epithelial cell layer of the Artyodactyla placenta. In the first part of the present work, two biochemical approaches were used to characterize PAGs isolated from zebu (Bos indicus) fetal cotyledons. The first procedure, used to isolate PAG from zebu placenta removed late in pregnancy, included extraction of proteins at neutral pH, acidic and ammonium sulfate precipitations, anion and cation exchange chromatographies. The second procedure, used to investigate PAG in placentas removed at early and mid gestational periods, included protein extractions at acid or alkaline pH followed by pepstatin-A agarose affinity chromatography. A bovine PAG radioimmunoassay was used to monitor the immunoreactivity throughout the isolation procedures. The most immunoreactive fractions issued from cation exchange and affinity chromatographies were analyzed by SDS-PAGE and Western Blot, before transfer to polyvinylidene difluoride (PVDF) membrane for NH2-microsequence determination. By use of SDS-PAGE and Western Blot, different isoforms of PAG with apparent molecular masses from 51 to 69 kDa and isoeletric points varying from 3.1 to 6.7 were identified in placentas from different gestational ages. After CM ceramic chromatography of all except 0.32 M NaCl DEAE fraction, the most immunoreactive proteins revealed N-terminal amino acid sequences (10 to 25 aa long) which were 100% identical to bovine PAG-1. The same sequence (14 aa long) was found after pepstatin-agarose affinity chromatography of proteins extracted from placentas removed earlier in pregnancy. These results converged towards the expression of one major N-terminal PAG amino acid sequence in zebu placentas at different gestational ages. In the second part of this study, two specific RIA systems were developed then used to measure plasmatic PAG concentrations during gestation and postpartum period in Azawak zebu cows. Twelve females palpated per rectum and diagnosed as pregnant were bled at 5-10 days interval approximately from Week 8 of gestation till Week 10 postpartum (pp). One zebu cow initially diagnosed as pregnant showed PAG concentrations lower than the assay sensitivity (<0.20 ng/ml) and did not calve. Another cow showed abnormally high PAG concentrations during gestation, being excluded from the general PAG profile. The 10 other zebu cows gave a very homogeneous PAG profile. In these animals, concentrations increased progressively from Week 8 to Week 35 of gestation (from 6.04.2 to 196.034.8 ng/ml), remaining relatively constant until Week 39 (210.874.8 ng/ml), when they increased sharply to reach their highest level (1,095.6607.2 ng/ml) at parturition. After delivery, PAG concentrations declined significantly (P<0.05) till the Week 2 postpartum (348.4  85.6 ng/ml) and slowly till the Week 10 postpartum. These results revealed that PAG concentrations in zebu cattle were lower than those previously described in taurine breeds between week 35 and 39 of gestation. [less ▲]

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