References of "1998"
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See detailCaractérisation des catalyseurs métalliques supportés
Heinrichs, Benoît ULg

Conference (1998, November 13)

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See detailEvaluation des enseignements en 1re et 2e candidatures, année académique 1997-1998 : rapport de synthèse
Gilles, Jean-Luc ULg; Collet, Marie; Debry, Marianne et al

Report (1998)

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See detailPositive Action in Belgium: Fragmentation or Reinforcement of Belgian Citizenship ?
Martiniello, Marco ULg

Scientific conference (1998, November 09)

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See detailPositive Action in Belgium: Fragmentation or Reinforcement of Belgian Citizenship ?
Martiniello, Marco ULg

Scientific conference (1998, November 06)

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See detailSuspension de l'exécution d'un permis d'urbanisme : conditions
Delnoy, Michel ULg

in Immobilier (1998), 20

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See detailRelative Reproductive success of males in polyandrous crosses of Barbus meridionalis (Cyprinidae) revealed by microsatellite genotyping
Chenuil, A.; Cattaneo-Berrebi, G.; Binda et al

in Folia Zoologica (1998), 47

Using microsatellite genotyping in Barbus meridionalis, we tried to assess the identity of fathers of progeny produced during four experimental polyandrous crosses involving the same four males and one or ... [more ▼]

Using microsatellite genotyping in Barbus meridionalis, we tried to assess the identity of fathers of progeny produced during four experimental polyandrous crosses involving the same four males and one or two females. The pooled analysis revealed that males had significantly different reproductive successes. We found no conspicuous causes explaining differential reproductive success in the behavioural data or in the physical characteristics of the males but a genetic determinism is the most parsimonious hypothesis to account for this variability. We argue that this conclusion is compatible with the hypothesis that the reproductive strategy of barbels, which involves large aggregations of males, is a result of sexual selection. This study provides guidelines for future interspecific crosses and constitutes the preliminary experiment of an investigation of the origin of a hybrid zone between Barbus barbus and Barbus meridionalis. [less ▲]

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See detailThree photometric methods tested on ground-based data of Q 2237+0305
Burud, I.; Stabell, R.; Magain, Pierre ULg et al

in Astronomy and Astrophysics (1998), 339

The Einstein Cross, Q 2237+0305, has been photometrically observed in four bands on two successive nights at NOT (La Palma, Spain) in October 1995. Three independent algorithms have been used to analyse ... [more ▼]

The Einstein Cross, Q 2237+0305, has been photometrically observed in four bands on two successive nights at NOT (La Palma, Spain) in October 1995. Three independent algorithms have been used to analyse the data: an automatic image decomposition technique, a CLEAN algorithm and the new MCS deconvolution code. The photometric and astrometric results obtained with the three methods are presented. No photometric variations were found in the four quasar images. Comparison of the photometry from the three techniques shows that both systematic and random errors affect each method. When the seeing is worse than 1farcs0 , the errors from the automatic image decomposition technique and the Clean algorithm tend to be large (0.04-0.1 magnitudes) while the deconvolution code still gives accurate results (1sigma error below 0.04) even for frames with seeing as bad as 1farcs7 . Reddening is observed in the quasar images and is found to be compatible with either extinction from the lensing galaxy or colour dependent microlensing. The photometric accuracy depends on the light distribution used to model the lensing galaxy. In particular, using a numerical galaxy model, as done with the MCS algorithm, makes the method less seeing dependent. Another advantage of using a numerical model is that eventual non-homogeneous structures in the galaxy can be modeled. Finally, we propose an observational strategy for a future photometric monitoring of the Einstein Cross. Based on observations obtained at NOT, La Palma. [less ▲]

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See detailDesign and verification of the Far Ultraviolet Spectrographic Imager (FUV-SI) for the IMAGE mission
Renotte, Etienne ULg; Habraken, Serge ULg; Rochus, Pierre ULg et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (1998, November 01)

The IMAGE FUV-SI is simultaneously imaging auroras at 121.8 nm and 135.8 nm. The spectrograph design challenge is the efficient rejection of the intense Lyman-alpha emission at 121.6 nm while passing its ... [more ▼]

The IMAGE FUV-SI is simultaneously imaging auroras at 121.8 nm and 135.8 nm. The spectrograph design challenge is the efficient rejection of the intense Lyman-alpha emission at 121.6 nm while passing its Doppler-shifted component at 121.8 nm. The FUV-SI opto-mechanical design, analysis integration, and verification of performances against environment are discussed in this paper. In absence of STM environmental constraints at subsystem levels are derived analytically from F.E.M. and used for pre-qualifying optical subsystems. [less ▲]

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See detailJuifs et Romains. Quelques jalons pour une histoire de l’antijudaïsme à Rome
Rochette, Bruno ULg

Scientific conference (1998, November)

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See detailCrossing of two mobile averages: A method for measuring the roughness exponent
Vandewalle, Nicolas ULg; Ausloos, Marcel ULg

in Physical Review. E : Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics (1998), 58(5), 6832-6834

Self-affine signals characterized by a defined Hurst (roughness) exponent H can be investigated through mobile averages. The density rho of crossing points between any two moving averages is a measure of ... [more ▼]

Self-affine signals characterized by a defined Hurst (roughness) exponent H can be investigated through mobile averages. The density rho of crossing points between any two moving averages is a measure of long-range power-law correlations in the signal. The method is compared to the detrended fluctuation analysis. We rake advantage of our findings in order to propose a practically powerful and accurate technique for determining H and apply it right away to cases with persistent or antipersistent correlations. [less ▲]

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See detailModèles conceptuels de la base de données Brussels UrbIS 2®© suivant les formalismes CONGOO et Entité/Relation - version 2
Billen, Roland ULg; Cornélis, Bernard; Pantazis, Dimos

Poster (1998, November)

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See detailShape signifiers for throttle control of a low-order compressor model
Sepulchre, Rodolphe ULg; Kokotovic, Petar

in IEEE Transactions on Automatic Control (1998), 43(11), 1643-1648

Rotating stall and surge, two instability mechanisms limiting the performance of aeroengines compressors, are studied on the third-order Moore–Greitzer model. The skewness of the compressor characteristic ... [more ▼]

Rotating stall and surge, two instability mechanisms limiting the performance of aeroengines compressors, are studied on the third-order Moore–Greitzer model. The skewness of the compressor characteristic, a single parameter shape signifier, is shown to determine the key qualitative properties of feedback control. [less ▲]

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See detailGestion de ressources humaines volatiles : la GRH à l’heure des Techniciens de l’Information
Schoenaers, Frédéric ULg; Zune, Marc

in collectif (Ed.) Actes du Congrès de l'AGRH (1998, November)

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See detailInterférométrie holographique avec cristaux photoréfractifs en régime impulsionnel. Développements et résultats préliminaires
Georges, Marc ULg; Pauliat, Gilles; Lemaire, Philippe et al

in Actes du 10e séminaire SFO/HOLO3 : Nouveaux moyens optiques pour l'industrie (1998, November)

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See detailLes effets de l'induction du travail sur le déroulement de l'accouchement
Gucciardo, L.; Thoumsin, H.; Foidart, Jean-Michel ULg

in Revue Médicale de Liège (1998), 53(11), 665-8

Labour induction has become a common practice. Given the significant number of induced deliveries carried out each year, it is important to know the consequences of this induction policy. The effects of ... [more ▼]

Labour induction has become a common practice. Given the significant number of induced deliveries carried out each year, it is important to know the consequences of this induction policy. The effects of labour induction on the childbirth are still the subject of considerable controversy. The increase of the caesarean and instrumental extraction rates has already been emphasized in previous studies. This article is based on an analysis of 10,045 deliveries carried out in the CHR Obstetrical Clinic of La Citadelle, between 1991 and 1997. The conclusions are instructive. Thus a departmental policy of setting an induction level of 35% will allocate 2/3 of the workload between 8:00 AM and 8:00 PM during the week, with a preponderance on Friday. The Caesarean rate is not increased but peridurals and recourse to instrumental extraction are more frequent. [less ▲]

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See detailMethod Development Strategies for the Enantioseparation of Drugs by Capillary Electrophoresis Using Cyclodextrins as Chiral Additives
Fillet, Marianne ULg; Hubert, Philippe ULg; Crommen, Jacques ULg

in Electrophoresis (1998), 19(16-17), 2834-40

General strategies for the development of capillary electrophoretic methods for the enantiomeric separation of basic, acidic or neutral drugs were developed. For all kinds of compounds, the use of a ... [more ▼]

General strategies for the development of capillary electrophoretic methods for the enantiomeric separation of basic, acidic or neutral drugs were developed. For all kinds of compounds, the use of a buffer made of 100 mM phosphoric acid adjusted to pH 3 with triethanolamine and containing anionic and/or uncharged cyclodextrin (CD) derivatives as chiral selectors was recommended. Two different optimization schemes depending on the acidic or basic character of the analytes, were elaborated. For most basic compounds present in cationic form at pH 3, enantiomeric separation could be achieved in the normal polarity mode. Different beta-cyclodextrin derivatives were first tested at a given concentration. Five derivatives were found to be particularly useful for enantioseparations in capillary electrophoresis (CE): the anionic carboxymethyl-beta-CD (CMCD) and sulfobutyl-beta-CD (SBCD) and the neutral dimethyl-beta-CD (DMCD), trimethyl-beta-CD (TMCD) and hydroxypropyl-beta-CD (HPCD). After selection of the most suitable CD, its concentration was optimized with respect to chiral resolution. If necessary, a further improvement in resolution could often be obtained for the enantiomers of cationic solutes by increasing the buffer pH from 3 to 5 using CMCD as chiral additive. Another possible alternative for enhancement in chiral resolution was the addition of metharlol or cyclohexanol to the buffer. For acidic drugs, essentially present in uncharged form at pH 3, and for neutral solutes, anionic CD derivatives such as SBCD or CMCD were first tested at a given concentration in the reversed polarity mode. Dual systems, based on the simultaneous addition of a charged CD (SBCD or CMCD) and a neutral CD (TMCD or DMCD), could then be investigated for resolution improvement. After optimization of the CD concentrations, the use of dual systems with CMCD at pH 5 could also be tested if necessary, especially for very weak acidic and neutral drugs. By applying these optimization strategies, 48 of the 50 drugs examined as model compounds could be fully enantioseparated by CE in short analysis times (usually less than 10 min). [less ▲]

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