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See detailInfluence of a nonlinear reference temperature profile on oscillatory Benard-Marangoni convection.
Dondlinger, M.; Colinet, P.; Dauby, Pierre ULg

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2003), 68(6 Pt 2), 066310

We analyze oscillatory instabilities in a fluid layer of infinite horizontal extent, heated from above or cooled from below, taking into account the nonlinearity of the reference temperature profile ... [more ▼]

We analyze oscillatory instabilities in a fluid layer of infinite horizontal extent, heated from above or cooled from below, taking into account the nonlinearity of the reference temperature profile during the transient state of heat conduction. The linear stability analysis shows that a nonlinear reference temperature profile can have a strong effect on the system, either stabilizing or destabilizing, depending on the relative importance of buoyancy and surface tension forces. For the nonlinear analysis we use a Galerkin-Eckhaus method leading to a finite set of amplitude equations. In the two-dimensional (2D) case, we show the solution of these amplitude equations are standing waves. [less ▲]

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See detailDeficient splines wavelets
Bastin, Françoise ULg; Laubin, P.; Kerner, R. et al

in Group 24 : Physical And Mathematical Aspects Of Symmetries (2003), 173

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See detailSolution structural study of BlaI: implications for the repression of genes involved in beta-lactam antibiotic resistance.
Melckebeke, Helene Van; Vreuls, Christelle ULg; Gans, Pierre et al

in Journal of Molecular Biology (2003), 333(4), 711-20

beta-Lactamase and penicillin-binding protein PBP2' mediate staphylococcal resistance to beta-lactam antibiotics, which are otherwise highly clinically effective. Two repressors (BlaI and MecI) regulate ... [more ▼]

beta-Lactamase and penicillin-binding protein PBP2' mediate staphylococcal resistance to beta-lactam antibiotics, which are otherwise highly clinically effective. Two repressors (BlaI and MecI) regulate expression of these inducible proteins. Here, we present the first solution structure of the 82 amino acid residue DNA-binding domain of Bacillus licheniformis BlaI which is very similar in primary sequence to the medically significant Staphyloccocal BlaI and MecI proteins. This structure is composed of a compact core of three alpha-helices and a three-stranded beta-sheet typical of the winged helix protein (WHP) family. The protein/DNA complex was studied by NMR chemical shift comparison between the free and complexed forms of BlaI. Residues involved in DNA interaction were identified and a WHP canonical model of interaction with the operators is proposed. In this model, specific contacts occur between the base-pairs of the TACA motif and conserved amino acid residues of the repressor helix H3. These results help toward understanding the repression and induction mechanism of the genes coding for beta-lactamase and PBP2'. [less ▲]

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See detailCharacterisation of different inulin samples by DSC - Influence of polymerisation degree on melting temperature
Blecker, Christophe ULg; Chevalier, J. P.; Fougnies, C. et al

in Journal of Thermal Analysis & Calorimetry (2003), 71(1), 215-224

Melting behaviour of powder inulin has been studied by differential scanning calorimetry. DSC curves show two endothermic peaks, relative to water elimination and to inulin melting, respectively. The ... [more ▼]

Melting behaviour of powder inulin has been studied by differential scanning calorimetry. DSC curves show two endothermic peaks, relative to water elimination and to inulin melting, respectively. The second peak is dependent on inulin type and a shift to a higher temperature is observed with increasing average polymerisation degree (DP) of the sample. For similar crystallinity index, linear relations have been underlined and so predicting inulin mean DP can be done by DSC analysis. The study shows that a relatively high heating rate (25degreesC min(-1)) can be used and brings a supplementary interest by an important reduction of analysis time. [less ▲]

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See detailEffect of rival males on the courtship of paedomorphic and metamorphic Triturus alpestris (Amphibia : Salamandridae)
Denoël, Mathieu ULg

in Copeia (2003), 2003(3), 618-623

Current theories on the alternative mating tactics suppose that individuals may opt for particular behavioral patterns depending of their morphological status. Facultative paedomorphosis in newts and ... [more ▼]

Current theories on the alternative mating tactics suppose that individuals may opt for particular behavioral patterns depending of their morphological status. Facultative paedomorphosis in newts and salamanders is a suitable process to explore this question because it implies the coexistence of two different morphological morphs differing by the presence of gills and epigamic traits. The aim of this study was to find out whether paedomorphs and metamorphs use similar tactics to attract mates in the presence of a rival and whether there are differences in sexual activity and success between alternative morphs. Sexual interactions in triadic encounters were staged and analyzed in a standardized experimental design. The two kinds of males did not differ in terms of sexual activity, spermatophore deposition or female responsiveness. Both rival paedomorphic and metamorphic males exhibited sexual interference, but in most encounters, intruders just disturbed the courting pair. Sperm transfer success was lower in triadic encounters than in dyadic encounters. These results illustrate that intermorph breeding also occurs in the presence of competitors but that the success rate of the newts is considerably decreased in such competitive situations. Moreover, newts do not use alternative reproductive tactics depending on their status (i.e., paedomorph or metamorph). [less ▲]

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See detailThe extraforaminal juxtafacet cyst as a rare cause of L5 radiculopathy: a case report.
Salmon, Bernard L; Deprez, Manuel ULg; Stevenaert, Achille ULg et al

in Spine (2003), 28(19), 405-7

STUDY DESIGN: This is a report of a case. OBJECTIVE: To document the clinical, radiographic, and histologic characteristics of a lumbar extraforaminal juxtafacet cyst. SUMMARY OF BACKGROUND DATA: Spinal ... [more ▼]

STUDY DESIGN: This is a report of a case. OBJECTIVE: To document the clinical, radiographic, and histologic characteristics of a lumbar extraforaminal juxtafacet cyst. SUMMARY OF BACKGROUND DATA: Spinal juxtafacet cysts develop most frequently at the dorsal aspect of the zygapophysial joint, sometimes in the posterolateral area of the canal. In one case, they have been described in the foraminal and extraforaminal region. METHODS: Description of the case report. RESULT: The authors report one case of a strictly extraforaminal juxtafacet cyst responsible for L5 sciatica. CONCLUSIONS: Juxtafacet cysts of the spine represent an infrequent cause of sciatica, usually when they grow in the canal, or more exceptionally when they occupy the foraminal or extraforaminal areas. [less ▲]

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See detail2D1/2 thermo-mechanical model of continuous casting using FEM
Pascon, Frédéric ULg; Habraken, Anne ULg

in Brucato, V. (Ed.) Proceedings of the 6th International ESAFORM Conference on Material Forming (2003)

Two complementary approaches of steel continuous casting modelling using the finite element code LAGAMINE have been developed in the M&S Department. The first one (at a macroscopic scale) describes the ... [more ▼]

Two complementary approaches of steel continuous casting modelling using the finite element code LAGAMINE have been developed in the M&S Department. The first one (at a macroscopic scale) describes the whole continuous casting process, from the free surface in the mould and through the entire machine, including thermal and mechanical behaviour of the steel. The second approach focuses on the prediction of cracks and is developed at grain scale. We present in this paper a description of the context in which the study started, the description of the macroscopic approach and some results. [less ▲]

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See detailAssociation of milk traits with SSCP polymorphisms at the growth hormone gene in the serrana goat
Marques, P. X.; Pereira, M.; Marques, M. R. et al

in Small Ruminant Research (2003), 50

The five exons and the 5' and 3'-untranslated regions (5'-UTR and 3'-UTR) of the oGH gene were screened for mutations using PCR-single strand conformation polymorphism (PCR-SSCP) procedures in 523 Serra ... [more ▼]

The five exons and the 5' and 3'-untranslated regions (5'-UTR and 3'-UTR) of the oGH gene were screened for mutations using PCR-single strand conformation polymorphism (PCR-SSCP) procedures in 523 Serra da Estrela ewes and were found to be highly polymorphic. The region extending across and between the GH2-N and GH2-Z copies was sequenced allowing the design of primers for the specific PCR amplification of each copy. These were cloned and sequenced in 20 animals representative of all SSCP patterns. The corresponding genotypes were established for each copy following nucleotide sequencing of SSCP alleles. Twenty-four polymorphic sites were found at the GH2-N (or GH1) and fourteen at the GH2-Z copies. Eight amino acid substitutions were predicted at the GH2-N and six at the GH2-Z copies. Milk yield adjusted to 150 lactation days was analysed for the genotype of each oGH gene copy taken separately or together (associated genotypes) by restricted maximum likelihood (REML) through a univariate best linear unbiased prediction (BLUP) animal model with repeated measures. Significant associations between genotypes and milk yield were observed. Within GH2-N genotypes there was a milk yield differential of 21.4+/-0.2 l/150 d between the most (N7) and the least (N5) productive ones. Within GH2-Z genotypes there was a differential of 21.6+/-0.2 l/150 d between the most (Z8) and the least (Z1) productive ones. The effect of associated GH2-N and GH2-Z genotypes revealed a differential of 39.6+/-0.3 l/150 d between the most (N1+Z7) and the least (N3+Z2) productive associated genotypes. The results show that GH2-N and GH2-Z genotypes significantly affect milk yield in Serra da Estrela ewes. Moreover, the apparent joint effect of GH2-N and GH2-Z genotype could improve milk yield in 25% as compared with the mean milk production of the analysed population. [less ▲]

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See detailLe cocher de Mithra
Swennen, Philippe ULg

in Religious themes and texts of pre-Islamic Iran and Central Asia (Studies in honour of Professor Gherardo Gnoli on the occasion of his 65th birthday on 6th December 2002) (2003)

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See detailMode Identification and Seismic Modelling of the Cep Star EN(16)Lac
Aerts, C.; Lehmann, H.; Scuflaire, Richard ULg et al

in Asteroseismology Across the HR Diagram (2003)

Not Available

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See detailPhotometric Mode Identification in the Two Doradus Stars HD 12901 and HD 48501
Aerts, C.; Cuypers, J.; Dupret, Marc-Antoine ULg et al

in Asteroseismology Across the HR Diagram (2003)

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See detailNon-adiabatic Pulsational Observables in Scuti and Doradus Stars: a Comparison of Different Numerical Codes
Moya, A.; Garrido, R.; Dupret, Marc-Antoine ULg

in Asteroseismology Across the HR Diagram (2003)

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See detailChronique de la 56ème Session de la Société Internationale Fernand de Visscher à Cagliari (17-21 Septembre 2002)
Gerkens, Jean-François ULg

in Revue Internationale des Droits de l'Antiquité [= RIDA] (2003), L

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See detailDe nouveaux entrelacs territoriaux, Globalisation et diversification des modes d'habiter.
Schmitz, Serge ULg

in Lask, Tomke (Ed.) Les constructions sociales de l'espace. Les territoires de l'anthropologie de la communicaiton. (2003)

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See detailPrevention de la vulnerabilite de la personne agee: un defi demographique.
Ethgen, Olivier ULg; Richy, F.; Gosset, Christiane ULg et al

in Revue Médicale de Liège (2003), 58(4), 175-82

World population is ageing. This phenomenon is unprecedented, universal, long-lasting and has important implications. Unprecedented, because never before in human history, so many individuals have reached ... [more ▼]

World population is ageing. This phenomenon is unprecedented, universal, long-lasting and has important implications. Unprecedented, because never before in human history, so many individuals have reached an advanced age. Universal, because all countries are now concerned. Long-lasting, because ageing started in the second half of the XXth century and will become even more pronounced over the XXIst century. With important implications, because it has and will have substantial consequences on human life and social composition. This article reviews quantitative data on ageing to appraise its extent and implication, the goal being to extend and stimulate the debate on ageing. International data are first presented, then analysis moves to Belgium estimates. [less ▲]

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See detailÉlaboration d'une base de données en vue de l'informatisation du catalogue de la cartothèque de l'Unité de documentation des Sciences de la Terre de l'Université de Liège
Borsus, Olivier ULg

Master's dissertation (2003)

Ce mémoire est destiné à l'Unité de Documentation (U.D.) des Sciences de la Terre de l'Université de Liège et consiste en l'élaboration d'une base de données pour le catalogue de son fonds cartographique ... [more ▼]

Ce mémoire est destiné à l'Unité de Documentation (U.D.) des Sciences de la Terre de l'Université de Liège et consiste en l'élaboration d'une base de données pour le catalogue de son fonds cartographique. En effet, l'interface LIBER utilisée à l'Université ne répond pas entièrement aux attentes de l'U.D en terme de critères de recherche spécifiques aux documents cartographiques. Par conséquent il était nécessaire de réaliser une interface conviviale et pratique pour la recherche et la saisie des références de ces cartes. Le logiciel utilisé est FileMaker Pro 5. Pour faciliter l'utilisation de cette base de données, un thésaurus reprenant tous les pays du monde a été créé. A cette fin, les difficultés dues aux changements de noms régionaux et nationaux résultant des évolutions historiques et politiques au fil du temps ont fait l'objet d'une attention particulière. [less ▲]

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See detailEnergies libres de surface des solides et des liquides: une approche de la compréhension des phénomènes interfaciaux
Courard, Luc ULg; Michel, Frédéric ULg

in Gagné, Richard (Ed.) Compte-rendu des Journées Scinetifiques du (RF)2B (2003)

Les propriétés de surface des matériaux conditionnent leur aptitude au mélange et à la réalisation de composites incluant deux ou plusieurs types de milieux différents. A coté des liaisons chimiques ... [more ▼]

Les propriétés de surface des matériaux conditionnent leur aptitude au mélange et à la réalisation de composites incluant deux ou plusieurs types de milieux différents. A coté des liaisons chimiques proprement dites et des aspects liés à l’interpénétration mécanique des matériaux, la thermodynamique des équilibres constitue une étape fondamentale pour comprendre les interactions potentielles au niveau de l’interface nouvellement créé. La loi de YOUNG-DUPRE, qui s’applique à l’équilibre entre une surface solide et un liquide, décrit les interactions qui se créent sur base des énergies libres des surfaces solides et liquides, de la tension interfaciale et de l’angle de contact solide - liquide. Les résultats présentés auront trait principalement au problème de la réparation des bétons et de la compatibilité des produits de réparation. [less ▲]

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See detailHow Daphnia copes with excess carbon in its food
Darchambeau, François ULg; Faerovig, P. J.; Hessen, D. O.

in Oecologia (2003), 136(3), 336-346

Animals that maintain near homeostatic elemental ratios may get rid of excess ingested elements from their food in different ways. C regulation was studied in juveniles of Daphnia magna feeding on two ... [more ▼]

Animals that maintain near homeostatic elemental ratios may get rid of excess ingested elements from their food in different ways. C regulation was studied in juveniles of Daphnia magna feeding on two Selenastrum capricornutum cultures contrasting in P content (400 and 80 C:P atomic ratios). Both cultures were labelled with C-14 in order to measure Daphnia ingestion and assimilation rates. No significant difference in ingestion rates was observed between P-low and P-rich food, whereas the net assimilation of C-14 was higher in the treatment with P-rich algae. Some Daphnia were also homogeneously labelled over 5 days on radioactive algae to estimate respiration rates and excretion rates of dissolved organic C (DOC). The respiration rate for Daphnia fed with high C:P algae (38.7% of body C day(-1)) was significantly higher than for those feeding on low C:P algae (25.3% of body C day(-1)). The DOC excretion rate was also higher when animals were fed on P-low algae (13.4% of body C day(-1)) than on P-rich algae (5.7% of body C day(-1)) . When corrected for respiratory losses, total assimilation of C did not differ significantly between treatments (around 60% of body C day(-1)). Judging from these experiments, D. magna can maintain its stoichiometric balance when feeding on unbalanced diets (high C:P) primarily by disposing of excess dietary C via respiration and excretion of DOC. [less ▲]

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See detailInteret des expectorations induites dans l'exploration de l'asthme.
Louis, Renaud ULg; Bettiol, Jane; Cataldo, Didier ULg et al

in Revue des Maladies Respiratoires (2003), 20(2 Pt 1), 215-23

INTRODUCTION: The technique of induced expectoration generates sputum by the inhalation of hypertonic saline. On account of its non-invasive character, its simplicity, its relative harmlessness, its cost ... [more ▼]

INTRODUCTION: The technique of induced expectoration generates sputum by the inhalation of hypertonic saline. On account of its non-invasive character, its simplicity, its relative harmlessness, its cost effectiveness and its reproducibility this technique, that appeared in the early 1990's, has rapidly established itself as the technique of choice in the investigation of bronchial inflammation in asthma. STATE OF THE ART: We present the results of our studies that have contributed to the validation of the technique at the methodological level and to the exploitation of the cellular contents as much as the fluid phase of the expectorations in characterising bronchial inflammation in asthmatics. Our results confirm an infiltration of the airways of asthmatics with eosinophils that appears to be proportional to the severity of the illness. We evaluate the effect of inhaled steroids and of theophylline on sputum eosinophilia and bronchial reactivity and discuss the role of eosinophils on bronchial hyperreactivity. Finally we discuss the use of induced expectoration in clinical practice in asthma. PERSPECTIVES: The analysis of induced sputum could well become a valuable tool in the clinical evaluation and monitoring of asthma in the same way as symptoms and abnormalities of lung function. CONCLUSIONS: Induced expectoration has certainly contributed to the understanding of the cellular and molecular mechanisms of asthma as well as the role of bronchial inflammation in the clinical manifestations of the disease. [less ▲]

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See detailCiel ouvert : la fin de l'attente
Dumoulin, André ULg

in Sur, Serge; Roche, Jean-Jacques (Eds.) Annuaire français de relations internationales 2003 (2003)

Le 1er janvier 2002 entrait en vigueur le traité sur le régime « Ciel ouvert ». Longtemps attendu, cette mesure de confiance et de sécurité repose sur la surveillance aérienne codifiée de pratiquement ... [more ▼]

Le 1er janvier 2002 entrait en vigueur le traité sur le régime « Ciel ouvert ». Longtemps attendu, cette mesure de confiance et de sécurité repose sur la surveillance aérienne codifiée de pratiquement tous les territoires d’États membres de l’OSCE, de l’Atlantique à l’Oural. Pur produit de la guerre froide, « Ciel ouvert » avait pour objectif de réduire la suspicion entre les États Parties. L’instabilité qui règne aujourd’hui dans certaines régions, le caractère complémentaire du régime par rapport au traité sur les Forces conventionnelles en Europe (FCE) et l’ouverture possible et à terme de « Ciel ouvert » à des nouvelles tâches grâce aux nouvelles technologies de surveillance aérienne, offrent à ce traité de nouvelles opportunités. [less ▲]

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