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See detailVLT + UVES spectroscopy of the low-ionization intrinsic absorber in SDSS J001130.56+005550.7
Hutsemekers, Damien ULg; Hall, Patrick; Brinkmann, J.

in Astronomy and Astrophysics (2004), 415

We analyse high-resolution VLT+UVES spectra of the low-ionization intrinsic absorber observed in the BAL QSO SDSS J001130.56+005550.7. Two narrow absorption systems at velocities -600 km s[SUP]-1[/SUP ... [more ▼]

We analyse high-resolution VLT+UVES spectra of the low-ionization intrinsic absorber observed in the BAL QSO SDSS J001130.56+005550.7. Two narrow absorption systems at velocities -600 km s[SUP]-1[/SUP] and -22 000 km s[SUP]-1[/SUP] are detected. The low-velocity system is part of the broad absorption line (BAL), while the high-velocity one is well detached. While most narrow absorption components are only detected in the high-ionization species, the lowest velocity component is detected in both high- and low-ionization species, including in the excited Si II[SUP]*[/SUP] and C II[SUP]*[/SUP] lines. From the analysis of doublet lines, we find that the narrow absorption lines at the low-velocity end of the BAL trough are completely saturated but do not reach zero flux, their profiles being dominated by a velocity-dependent covering factor. The covering factor is significantly smaller for Mg II than for Si IV and N V , which demonstrates the intrinsic nature of absorber. From the analysis of the excited Si II[SUP]*[/SUP] and C II[SUP]*[/SUP] lines in the lowest velocity component, we find an electron density ~=10[SUP]3[/SUP] cm[SUP]-3[/SUP]. Assuming photoionization equilibrium, we derive a distance ~=20 kpc between the low-ionization region and the quasar core. The correspondence in velocity of the high- and low-ionization features suggests that all these species must be closely associated, hence formed at the same distance of Ë 20 kpc, much higher than the distance usually assumed for BAL absorbers. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile (ESO 267.A-5698). [less ▲]

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See detailMAGRITTE: an instrument suite for the solar atmospheric imaging assembly (AIA) aboard the Solar Dynamics Observatory
Rochus, Pierre ULg; Defise, Jean-Marc ULg; Halain, Jean-Philippe ULg et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2004, February 01)

The Solar Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory will characterize the dynamical evolution of the solar plasma from the chromosphere to the corona, and will follow the ... [more ▼]

The Solar Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory will characterize the dynamical evolution of the solar plasma from the chromosphere to the corona, and will follow the connection of plasma dynamics with magnetic activity throughout the solar atmosphere. The AIA consists of 7 high-resolution imaging telescopes in the following spectral bandpasses: 1215Å. Ly-a, 304 Å He II, 629 Å OV, 465 Å Ne VII, 195 Å Fe XII (includes Fe XXIV), 284 Å Fe XV, and 335 Å Fe XVI. The telescopes are grouped by instrumental approach: the MAGRITTE Filtergraphs (R. MAGRITTE, famous 20th Century Belgian Surrealistic Artist), five multilayer EUV channels with bandpasses ranging from 195 to 1216 Å, and the SPECTRE Spectroheliograph with one soft-EUV channel at OV 629 Å. They will be simultaneously operated with a 10-second imaging cadence. These two instruments, the electronic boxes and two redundant Guide Telescopes (GT) constitute the AIA suite. They will be mounted and coaligned on a dedicated common optical bench. The GTs will provide pointing jitter information to the whole SHARPP assembly. This paper presents the selected technologies, the different challenges, the trade-offs to be made in phase A, and the model philosophy. From a scientific viewpoint, the unique combination high temporal and spatial resolutions with the simultaneous multi-channel capability will allow MAGRITTE / SPECTRE to explore new domains in the dynamics of the solar atmosphere, in particular the fast small-scale phenomena. We show how the spectral channels of the different instruments were derived to fulfill the AIA scientific objectives, and we outline how this imager array will address key science issues, like the transition region and coronal waves or flare precursors, in coordination with other SDO experiments. We finally describe the real-time solar monitoring products that will be made available for space-weather forecasting applications. [less ▲]

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See detailAcidophilic adaptation of family 11 endo--1,4-xylanases: Modeling and mutational analysis
De Lemos Esteves, Frédéric ULg; Ruelle, Virginie; Lamotte-Brasseur, Josette ULg et al

in Protein Science : A Publication of the Protein Society (2004), 13(5), 12091218

Xyl1 from Streptomyces sp. S38 belongs to the low molecular mass family 11 of endo--1,4-xylanases. Its three-dimensional structure has been solved at 2.0 Å and its optimum temperature and pH for enzymatic ... [more ▼]

Xyl1 from Streptomyces sp. S38 belongs to the low molecular mass family 11 of endo--1,4-xylanases. Its three-dimensional structure has been solved at 2.0 Å and its optimum temperature and pH for enzymatic activity are 60°C and 6.0, respectively. Aspergillus kawachii xylanase XynC belongs to the same family but is an acidophilic enzyme with an optimum pH of 2.0. Structural comparison of Xyl1 and XynC showed differences in residues surrounding the two glutamic acid side chains involved in the catalysis that could be responsible for the acidophilic adaptation of XynC. Mutations W20Y, N48D, A134E, and Y193W were introduced by site-directed mutagenesis and combined in multiple mutants. Trp 20 and Tyr 193 are involved in substrate binding. The Y193W mutation inactivated Xyl1 whereas W20Y decreased the optimum pH of Xyl1 to 5.0 and slightly increased its specific activity. The N48D mutation also decreased the optimum pH of Xyl1 by one unit. The A134E substitution did not induce any change, but when combined with N48D, a synergistic effect was observed with a 1.4 unit decrease in the optimum pH. Modeling showed that the orientations of residue 193 and of the fully conserved Arg 131 are different in acidophilic and alkaline xylanases whereas the introduced Tyr 20 probably modifies the pKa of the acid-base catalyst via residue Asn 48. Docking of a substrate analog in the catalytic site highlighted striking differences between Xyl1 and XynC in substrate binding. Hydrophobicity calculations showed a correlation between acidophilic adaptation and a decreased hydrophobicity around the two glutamic acid side chains involved in catalysis. [less ▲]

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See detailNebulised salbutamol administered during sputum induction improves bronchoprotection in patients with asthma
Delvaux, Muriel ULg; Henket, Monique ULg; Lau, L. et al

in Thorax (2004), 59(2), 111-115

Background: Inhalation of hypertonic or even isotonic saline during sputum induction may cause bronchospasm in susceptible patients with asthma, despite premedication with 400 mug inhaled salbutamol ... [more ▼]

Background: Inhalation of hypertonic or even isotonic saline during sputum induction may cause bronchospasm in susceptible patients with asthma, despite premedication with 400 mug inhaled salbutamol delivered by pressurised metered dose inhaler (pMDI). The bronchoprotection afforded by additional inhaled salbutamol administered through the ultrasonic nebuliser during sputum induction was investigated. Methods: Twenty patients with moderate to severe asthma underwent sputum induction by inhaling saline 4.5% (or 0.9% if post-bronchodilation forced expiratory volume in 1 second (FEV1) <65% predicted) for 10 minutes according to two protocols given 1 week apart in random order. At visit A the patients received 400 mg salbutamol administered through a pMDI + spacer 20 minutes before induction while at visit B the premedication was supplemented by 1500 mg nebulised salbutamol inhaled throughout the induction procedure. Both the investigator and the patients were blind to the nebulised solution used. FEV1 was recorded during sputum induction at 1, 3, 5, and 10 minutes. Sputum cell counts and histamine, tryptase and albumin levels in the supernatants were determined. Results: The mean (SE) maximal reduction in FEV1 over the 10 minute period of sputum induction was 11.7 (2.8)% at visit A, which was significantly greater than at visit B (2.6 (1.2)%; mean difference 9% (95% CI 2.7 to 15.4), p < 0.01). Total and differential sputum cell counts as well as albumin, tryptase, and histamine levels did not differ between the two visits. Conclusion: The addition of inhaled salbutamol through an ultrasonic nebuliser markedly improves bronchoprotection against saline induced bronchoconstriction in patients with moderate to severe asthma undergoing sputum induction without affecting cell counts and inflammatory markers. [less ▲]

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See detailUnderstanding bilingual memory: models and data
French, R.; Jacquet, Maud ULg

in Trends in Cognitive Sciences (2004), 8(2), 87-93

Bilingual memory research in the past decade and, particularly, in the past five years, has developed a range of sophisticated experimental, neuropsychological and computational techniques that have ... [more ▼]

Bilingual memory research in the past decade and, particularly, in the past five years, has developed a range of sophisticated experimental, neuropsychological and computational techniques that have allowed researchers to begin to answer some of the major long-standing questions of the field. We explore bilingual memory along the lines of the conceptual division of language knowledge and organization, on the one hand, and the mechanisms that operate on that knowledge and organization, on the other. Various interactive-activation and connectionist models of bilingual memory that attempt to incorporate both organizational and operational considerations will serve to bridge these two divisions. Much progress has been made in recent years in bilingual memory research, which also serves to illuminate general (language-independent) memory processes. [less ▲]

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See detailSustained antihypertensive activity of telmisartan vs valsartan
Lacourciere, Yves; Krzesinski, Jean-Marie ULg; White, William et al

Poster (2004, February)

DBP reduction in the last 6 h of the once-daily dosing interval and 24-h mean DBP control when a dose is missed are significantly superior with telmisartan than with valsartan. Thus, telmisartan due to ... [more ▼]

DBP reduction in the last 6 h of the once-daily dosing interval and 24-h mean DBP control when a dose is missed are significantly superior with telmisartan than with valsartan. Thus, telmisartan due to its longer half-life offers more sustained BP control, especially at the end of the dosing period and provides sustained efficacy in poorly compliant patients. [less ▲]

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See detailCONVENTION ''PLAN DE L'AIR EN REGION WALLONNE'' Rapport final – Partie ''odeurs'' Etude comparative des différentes méthodes de caractérisation quantitative et qualitative des odeurs dans l'environnement dans le but de déterminer une méthode applicable en région wallonne.
Nicolas, Jacques ULg; Craffe, Flavien

Report (2004)

The report presents a part of a complete study aiming at inventory policies, standards and measurement methods for air quality assessment. It concerns more particularly the "odour" part and considers ... [more ▼]

The report presents a part of a complete study aiming at inventory policies, standards and measurement methods for air quality assessment. It concerns more particularly the "odour" part and considers qualitative and quantitative methods, key odorous compounds, standards and guidelines for odour assessment. [less ▲]

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See detailAdenylation-dependent conformation and unfolding pathways of the NAD(+)-dependent DNA ligase from the thermophile Thermus scotoductus
Georlette, D.; Blaise, Vinciane ULg; Bouillenne, Fabrice ULg et al

in Biophysical Journal (2004), 86(2), 1089-1104

In the last few years, an increased attention has been focused on NAD(+)-dependent DNA ligases. This is mostly due to their potential use as antibiotic targets, because effective inhibition of these ... [more ▼]

In the last few years, an increased attention has been focused on NAD(+)-dependent DNA ligases. This is mostly due to their potential use as antibiotic targets, because effective inhibition of these essential enzymes would result in the death of the bacterium. However, development of an efficient drug requires that the conformational modifications involved in the catalysis of NAD(+)-dependent DNA ligases are understood. From this perspective, we have investigated the conformational changes occurring in the thermophilic Thermus scotoductus NAD(+)-DNA ligase upon adenylation, as well as the effect of cofactor binding on protein resistance to thermal and chemical (guanidine hydrochloride) denaturation. Our results indicate that cofactor binding induces conformational rearrangement within the active site and promotes a compaction of the enzyme. These data support an induced "open-closure" process upon adenylation, leading to the formation of the catalytically active enzyme that is able to bind DNA. These conformational changes are likely to be associated with the protein function, preventing the formation of nonproductive complexes between deadenylated ligases and DNA. In addition, enzyme adenylation significantly increases resistance of the protein to thermal denaturation and GdmCl-induced unfolding, establishing a thermodynamic link between ligand binding and increased conformational stability. Finally, chemical unfolding of deadenylated and adenylated enzyme is accompanied by accumulation of at least two equilibrium intermediates, the molten globule and premolten globule states. Maximal populations of these intermediates are shifted toward higher GdmCl concentrations in the case of the adenylated ligase. These data provide further insights into the properties of partially folded intermediates. [less ▲]

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See detailNumerical modelling of steel beam-columns in case of fire - comparisons with Eurocode 3
Vila Real, Paulo; Lopes, Nuno; da Silva, Luis Simoes et al

in Fire Safety Journal (2004), 39(1), 23-39

This paper presents a numerical study of the behaviour of steel I-beams subjected to fire and a combination of axial force and bending moments. A geometrical and material non-linear finite element program ... [more ▼]

This paper presents a numerical study of the behaviour of steel I-beams subjected to fire and a combination of axial force and bending moments. A geometrical and material non-linear finite element program, specially established in Liege for the analysis of structures submitted to fire, has been used to determine the resistance of a beam-column at elevated temperature, using the material properties of Eurocode 3, part 1-2. The numerical results have been compared with those obtained with the Eurocode 3, part 1-2 (1995) and the new version of the same Eurocode (2002). The results have confirmed that the new proposal for Eurocode 3 (2002) is more conservative than the ENV-EC3 (1995) approach. (C) 2003 Elsevier Ltd. All rights reserved. [less ▲]

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See detailDesign of an implantable micropump
Smal, Olivier; Merken, Patrick; Croquet, Vincent et al

in Proceedings of the International Precision Assembly Seminar (2004, February)

The implantable programmable micropump is an interesting solution to treat chronic diseases such as diabetes with regular micro-injections of medicine. However, current applications of micropumps are ... [more ▼]

The implantable programmable micropump is an interesting solution to treat chronic diseases such as diabetes with regular micro-injections of medicine. However, current applications of micropumps are limited by their rather expensive cost. The challenge is therefore to develop a low cost alternative by reducing the number of parts and by simplifying the assembly. As the pump and its tank will be placed under the skin in order to increase comfort, such a system should be small and reliable. In this paper, we present the micropump we developed within the framework of the 4M-µ pump interuniversity project (Methods and Means for the Miniaturization of Machines). [less ▲]

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See detailNuclear bodies and compartmentalization of pre-mRNA splicing factors in higher plants
Docquier, Sarah; Tillemans, Vinciane ULg; Deltour, Roger et al

in Chromosoma (2004), 112(5), 255-266

We studied the fine structural organization of nuclear bodies in the root meristem during germination of maize and Arabidopsis thaliana using electron microscopy (EM). Cajal bodies (CBs) were observed in ... [more ▼]

We studied the fine structural organization of nuclear bodies in the root meristem during germination of maize and Arabidopsis thaliana using electron microscopy (EM). Cajal bodies (CBs) were observed in quiescent embryos as well as germinating cells in both species. The number and distribution of CBs were investigated. To characterize the nuclear splicing domains, immunofluorescence labelling with antibodies against splicing factors (U2B" and m3G-snRNAs) and in situ hybridisation (with U1/U6 antisense probes) were performed combined with confocal microscopy. Antibodies specific to the Arabidopsis SR splicing factor atRSp31 were produced. AtRSp31 was detected in quiescent nuclei and in germinating cells. This study revealed an unexpected nuclear speckled organization of atRSp31 in root epidermal cells where micro clusters of interchromatin granules were also observed by EM. Therefore, we examined the distribution of green fluorescent protein (GFP)-tagged atRSp31 in living cells after Agrobacterium-mediated transient expression. When expressed transiently, atRSp31-GFP exhibited a speckled distribution in leaf cells. Treatments with -amanitin, okadaic acid, staurosporine or heat-shock induced the speckles to reorganize. Furthermore, we have generated stable Arabidopsis transgenics expressing atRSp31-GFP. The distribution of the fusion protein was identical to the endogenous atRSp31. Three-dimensional time-lapse confocal microscopy showed that speckles were highly dynamic domains over time. [less ▲]

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See detailRegulation of HER-2 oncogene expression by cyclooxygenase-2 and prostaglandin E2
Benoit, Valérie; Relic, Biserka ULg; de Leval, Laurence ULg et al

in Oncogene (2004), 23(8), 1631-1635

The oncoprotein HER-2/neu is a prosurvival factor and its overexpression has been correlated with adverse prognosis in breast cancers. High levels of the cyclooxygenase-2 (COX-2), a proinflammatory and ... [more ▼]

The oncoprotein HER-2/neu is a prosurvival factor and its overexpression has been correlated with adverse prognosis in breast cancers. High levels of the cyclooxygenase-2 (COX-2), a proinflammatory and antiapoptotic enzyme, were detected in HER-2-positive tumors and this observation was linked to an HER-2-mediated induction of COX-2 gene transcription. Here, we report that COX-2 expression, and synthesis of its major enzymatic product, PGE2, leads in turn to an enhanced HER-2 expression. Moreover, COX-2 enzymatic inhibition dramatically reduced HER-2 protein levels, efficiently increased the cancer cells sensitility to chemotherapeutic treatment and acted in synergy with HER-2 inhibitor, trastuzumab. Therefore, we propose an original model where HER-2 and COX-2 transcriptionally regulate each other in a positive loop. [less ▲]

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See detailSome like it cold: biocatalysis at low temperatures
Georlette, D.; Blaise, Vinciane ULg; Collins, T. et al

in FEMS Microbiology Reviews (2004), 28(1), 25-42

In the last few years, increased attention has been focused on a class of organisms called psychrophiles. These organisms, hosts of permanently cold habitats, often display metabolic fluxes more or less ... [more ▼]

In the last few years, increased attention has been focused on a class of organisms called psychrophiles. These organisms, hosts of permanently cold habitats, often display metabolic fluxes more or less comparable to those exhibited by mesophilic organisms at moderate temperatures. Psychrophiles have evolved by producing, among other peculiarities, "cold-adapted" enzymes which have the properties to cope with the reduction of chemical reaction rates induced by low temperatures. Thermal compensation in these enzymes is reached, in most cases, through a high catalytic efficiency associated, however, with a low thermal stability. Thanks to recent advances provided by X-ray crystallography, structure modelling, protein engineering and biophysical studies, the adaptation strategies are beginning to be understood. The emerging picture suggests that psychrophilic enzymes are characterized by an improved flexibility of the structural components involved in the catalytic cycle, whereas other protein regions, if not implicated in catalysis, may be even more rigid than their mesophilic counterparts. Due to their attractive properties, i.e., a high specific activity and a low thermal stability, these enzymes constitute a tremendous potential for fundamental research and biotechnological applications. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier B.V. All rights reserved. [less ▲]

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See detailAnevrysmes mycotiques primaires de l'aorte sous-renale. A propos de deux cas
Rousie, Céline ULg; Van Damme, Hendrik ULg; Limet, Raymond ULg

in Revue Médicale de Liège (2004), 59(2), 89-94

Infrarenal mycotic aneurysms are rare. The classic symptomatic triad is abdominal pain, fever and a pulsatile, rapidly growing abdominal mass. We present two cases of mycotic abdominal aneurysm, recently ... [more ▼]

Infrarenal mycotic aneurysms are rare. The classic symptomatic triad is abdominal pain, fever and a pulsatile, rapidly growing abdominal mass. We present two cases of mycotic abdominal aneurysm, recently managed. The principles of diagnosis and treatment of mycotic aneurysm are reviewed and discussed. [less ▲]

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See detailBelgium's Undocumented Hold Lessons for EU
Martiniello, Marco ULg; Rea, Andrea

in Migration Information Source (2004)

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See detailMeer samen, beter toegankelijk. De maatschappelijke kracht van de sport verkend
Vincke, John; Cloes, Marc ULg

Book published by Koning Boudewijnstichting (2004)

This book aimed to propose policies designed to develop social links through sport and to improve the access to sport and physical activity.

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See detailLe cas clinique du mois. Cirrhose autoimmune traitee par transplantation hepatique 'a partir d'un lobe hepatique droit preleve chez un donneur vivant
Detry, Olivier ULg; De Roover, Arnaud ULg; Coimbra Marques, Carla ULg et al

in Revue Médicale de Liège (2004), 59(2), 69-74

The authors describe the case of a 17-year-old girl who suffered from end-stage liver failure due to chronic autoimmune hepatitis. Liver failure was complicated by severe portal hypertension ... [more ▼]

The authors describe the case of a 17-year-old girl who suffered from end-stage liver failure due to chronic autoimmune hepatitis. Liver failure was complicated by severe portal hypertension, hypersplenism and refractory ascites. Liver transplantation was indicated. She was listed for cadaveric whole liver transplantation, but her infrequent blood group (B) increased waiting time. Her condition deteriorated to Child C liver failure and living related liver transplant was considered. Her father was compatible and proposed himself for donation. Right lobe procurement was decided in order to provide sufficient liver mass. No transfusion of red cells, platelets, or fresh frozen plasma was used either in the donor or the recipient. Both recipient and donor left the ward at postoperative day 14, without complication. They were both asymptomatic and with normal liver tests at one year follow-up. Living related liver transplantation using the right lobe may offer an alternative to liver transplant candidates in this period of organ donor shortage. [less ▲]

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See detailAn educational simulation tool for power system control and stability
Vournas, Costas; Potamianakis, Emmanuel G.; Moors, Cédric et al

in IEEE Transactions on Power Systems (2004), 19(1), 48-55

This paper presents a Simulink-based educational tool developed for the purpose of illustrating power system control and stability notions as well as introducing students to realistic, though tractable in ... [more ▼]

This paper presents a Simulink-based educational tool developed for the purpose of illustrating power system control and stability notions as well as introducing students to realistic, though tractable in size, design problems. Relevant courses are taught to last-year undergraduate as well as graduate students at the University of, Liege, Belgium, and the National Technical University of Athens, Greece.. After a brief description of the corresponding curricula, the paper describes the simulation tool and gives examples of problems and assignments given to the students. [less ▲]

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