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See detailBulletin agrométéorologique - Juillet 2004
Tychon, Bernard ULg; Ozer, Pierre ULg; Horion, S. et al

in Bulletin Agrométéorologique (2004), 3(4), 1-4

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See detailDynamical study of the pentaquark antidecuplet
Stancu, Floarea ULg

in Physics Letters B (2004), 595

Dynamical calculations are performed for all isomultiplets of the flavour antidecuplet to which the newly discovered pentaquark Theta(+) belongs. The framework is a constituent quark model where the short ... [more ▼]

Dynamical calculations are performed for all isomultiplets of the flavour antidecuplet to which the newly discovered pentaquark Theta(+) belongs. The framework is a constituent quark model where the short-range interaction has a flavour-spin structure. In this model the lowest pentaquarks have positive parity. Each antidecuplet member is described by a variational solution with the Pauli principle properly taken into account. By fitting the mass of Theta(+) of minimal content uudd, the mass of Xi(--), of minimal content ddss (u) over bar, is predicted at approximately 1960 MeV. The influence of the octet-antidecuplet mixing on the masses of the Y = I and 0 pentaquarks is considered within the same model and the role of the hyperfine interaction in this mixing is pointed out. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

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See detailLes territoires paysagers de Wallonie, première étape de connaissance en vue de la mise en œuvre de la Convention européenne du paysage en Région wallonne
Droeven, Emilie ULg; Kummert, Magali

in Conférence de la Convention européenne du paysage à l’occasion de son entrée en vigueur. Conseil de l’Europe, Palais de l’Europe, Strasbourg 17 juin 2004. Rapport (2004)

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See detailFocii determination of an off axis ellipsoid : Theory to practice
Houbrechts, Yvette ULg; Roose, Stéphane ULg; Stockman, Yvan ULg

in Osten, W.; Novak, E. (Eds.) Proceedings of the Eighth International Conference on Laser and Laser Information Technologies (2004, August 02)

In the frame of cryogenic test on an off axis ellipsoid, it has been required to set-up an unambiguous method to determine and track the foci position during temperature transitions. This procedure was ... [more ▼]

In the frame of cryogenic test on an off axis ellipsoid, it has been required to set-up an unambiguous method to determine and track the foci position during temperature transitions. This procedure was mandatory to avoid: (1) impact of the operator skills working on triple shift scheme to assure continuously monitoring of the ellipsoid shape during cool down. (2) correctly dissociate the impact of the thermal deformation on the mirror shape with respect to alignment errors. This paper will demonstrate the process, starting from ideal ellipsoid shape, then introducing 3D metrology data in a model, and finally presents the results in a practical situation. [less ▲]

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See detailAbout the methods of preparation of poly(ethylene oxide)-b-poly(epsilon-caprolactone) nanoparticles in water. Analysis by dynamic light scattering
Vangeyte, Patrick; Gautier, Sandrine; Jérôme, Robert ULg

in Colloids and Surfaces A : Physicochemical and Engineering Aspects (2004), 242(1-3), 203-211

Self-assembly of nonionic amphiphilic poly(ethylene oxide)-b-poly(ε-caprolactone) (PEO-b-PCL) and poly(ethylene oxide)-b-poly(γ-methyl-ε-caprolactone) (PEO-b-PMCL) has been studied in water by dynamic ... [more ▼]

Self-assembly of nonionic amphiphilic poly(ethylene oxide)-b-poly(ε-caprolactone) (PEO-b-PCL) and poly(ethylene oxide)-b-poly(γ-methyl-ε-caprolactone) (PEO-b-PMCL) has been studied in water by dynamic light scattering (DLS). The aqueous solutions have been prepared by three methods, i.e., dialysis of solutions in a common organic solvent against water, rapid addition of water to organic solutions, and rapid addition of organic solutions into water. Several common organic solvents have been used: tetrahydrofuran (THF), dimethylformamide (DMF), dimethylacetamide (DMAc) and dimethylsulfoxide (DMSO). The dialysis method is not reproducible and leads to very large and polydispersed particles (~1µm). In contrast, nanoparticles are formed by the two other methods with a low polydispersity and a size in the 30-10 nm range, depending on the organic solvent used. The particle size increases when the concentration in the organic solvent is decreased. The effect of temperature and length of the hydrophobic block has also been studied. [less ▲]

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See detailOn the determination of oxygen abundances in chromospherically active stars
Morel, Thierry ULg; Micela, G.

in Astronomy and Astrophysics (2004), 423

We discuss oxygen abundances derived from [O I] λ6300s and the O I triplet in stars spanning a wide range in chromospheric activity level, and show that these two indicators yield increasingly discrepant ... [more ▼]

We discuss oxygen abundances derived from [O I] λ6300s and the O I triplet in stars spanning a wide range in chromospheric activity level, and show that these two indicators yield increasingly discrepant results with higher chromospheric/coronal activity measures. While the forbidden and permitted lines give fairly consistent results for solar-type disk dwarfs, spuriously high O I triplet abundances are observed in young Hyades and Pleiades stars, as well as in individual components of RS CVn binaries (up to 1.8 dex). The distinct behaviour of the [O I]-based abundances which consistently remain near-solar suggests that this phenomenon mostly results from large departures from LTE affecting the O I triplet at high activity level that are currently unaccounted for, but also possibly from a failure to adequately model the atmospheres of K-type stars. These results suggest that some caution should be exercised when interpreting oxygen abundances in active binaries or young open cluster stars. Based on observations collected at the European Southern Observatory, Chile (Proposals 64.L-0249 and 071.D-0260). Table \ref{tab_data} is only available in electronic form at http://www.edpsciences.org [less ▲]

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See detailSynthesis of data availability for the river Meuse and the aquifer located in the alluvial plain in the Walloon Meuse catchment region
Batlle-Aguilar, Jordi; Popescu, Ileana-Cristina; Orban, Philippe ULg et al

Report (2004)

During the three first months of the AQUATERRA project, the Group of Hydrogeology and Environmental Geology from the University of Liège (HGULg) has performed a general inventory of data sources and ... [more ▼]

During the three first months of the AQUATERRA project, the Group of Hydrogeology and Environmental Geology from the University of Liège (HGULg) has performed a general inventory of data sources and availability for the Walloon part of the Meuse basin in Belgium. This deliverable provides the information in the form of a summary table that gives a general description of data types, accessibility (public or confidential, free or charged…) and, if existing, a website with further useful information. In this synthesis, emphasis is put on hydrogeological information. However, general information on surface water is also provided when available. In the following months, needed data will be collected for the Meuse/Basin experimental sites in the Walloon region. Collected datasets will be introduced into the Hydrogeological Database HYGES developed by HGULg. This database is presently updated for the needs of the AQUATERRA Project. This synthesis will be further updated when new information and data sources are available. [less ▲]

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See detailOrganisation of « sport + studies programmes » at secondary school level: the perceptions of the students and the staff
Cloes, Marc ULg

in Klissouras, V.; Kellis, S.; Mouratidis, I. (Eds.) Proceedings of the 2004 Pre-Olympic Congress. Sport Science through the Ages. (2004, August)

It is undeniable that sporting success requires an intensive practice, increasingly early and strictly supervised. This necessarily implies that the young athltes find a balance btween the sporting and ... [more ▼]

It is undeniable that sporting success requires an intensive practice, increasingly early and strictly supervised. This necessarily implies that the young athltes find a balance btween the sporting and school education. All around the world, seceral organisations were proposed in order to facilitate the task of the sporting hopes and to enable them to encure their future life as well as possible. [less ▲]

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See detailMigration of contaminants through the unsaturated zone overlying the Hesbaye chalky aquifer in Belgium: a field investigation
Brouyère, Serge ULg; Dassargues, Alain ULg; Hallet, Vincent

in Journal of Contaminant Hydrology (2004), 72(1-4), 135-164

This paper presents the results of a detailed field investigation that was performed for studying groundwater recharge processes and solute downward migration mechanisms prevailing in the unsaturated zone ... [more ▼]

This paper presents the results of a detailed field investigation that was performed for studying groundwater recharge processes and solute downward migration mechanisms prevailing in the unsaturated zone overlying a chalk aquifer in Belgium. Various laboratory measurements were performed on core samples collected during the drilling of boreholes in the experimental site. In the field, experiments consisted of well logging, infiltration tests in the unsaturated zone, pumping tests in the saturated zone and tracer tests in both the saturated and unsaturated zones. Results show that gravitational flows govern groundwater recharge and solute migration mechanisms in the unsaturated zone. In the variably saturated chalk, the migration and retardation of solutes is strongly influenced by recharge conditions. Under intense injection conditions, solutes migrate at high speed along the partially saturated fissures, downward to the saturated zone. At the same time, they are temporarily retarded in the almost immobile water located in the chalk matrix. Under normal recharge conditions, fissures are inactive and solutes migrate slowly through the chalk matrix. Results also show that concentration dynamics in the saturated zone are related to fluctuations of groundwater levels in the aquifer. A conceptual model is proposed to explain the hydrodispersive behaviour of the variably saturated chalk. Finally, the vulnerability of the chalk to contamination issues occurring at the land surface is discussed. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailPorous poly(α-hydroxyacid)/Bioglass® composite scaffolds for bone tissue engineering. I: preparation and in vitro characterisation
Maquet, Véronique; Boccaccini, Aldo R.; Pravata, Laurent et al

in Biomaterials (2004), 25(18), 4185-4194

Highly porous composites scaffolds of poly-D,L-lactide (PDLLA) and poly(lactide-co-glycolide) (PLGA) containing different amounts (10, 25 and 50wt%) of bioactive glass (45S5 bioglass®) were prepared by ... [more ▼]

Highly porous composites scaffolds of poly-D,L-lactide (PDLLA) and poly(lactide-co-glycolide) (PLGA) containing different amounts (10, 25 and 50wt%) of bioactive glass (45S5 bioglass®) were prepared by thermally induced solid-liquid phase separation (TIPS) and subsequent solvent sublimation. The addition of increasing amounts of bioglass® into the polymer foams decreased the pore volume. Conversely, the mechanical properties of the polymer materials were improved. The composites were incubated in phosphate buffer saline at 37°C to study the in vitro degradation of the polymer by measurement of water absorption, weight loss as well as changes in the average molecular weight of the polymer and in the pH of the incubation medium as a function of the incubation time. The addition of bioglass®to polymer foams increased the water absorption and weight loss compared to neat polymer foams. However, the polymer molecular weight, determined by size exclusion chromatography, was found to decrease more rapidly and to a larger extent in absence of bioglass®. The presence of the bioactive filler was therefore found to delay the degradation rate of the polymer as compared to the neat polymer foams. Formation of hydroxyapatite on the surface of composites, as an indication of their bioactivity, was recorded by EDXA, X-ray diffractometry and confirmed by Raman spectroscopy. [less ▲]

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See detailAnalysis of the volleyball spike: relationships between several parameters and the speed of the ball
Cloes, Marc ULg; Croisier, Jean-Louis ULg; Barsin, M. et al

Poster (2004, August)

In volleyball, the spike's effectiveness is a determining element of the team's success. To perform at a high level, a player must be able to produce spikes characterized by a speed of the ball that ... [more ▼]

In volleyball, the spike's effectiveness is a determining element of the team's success. To perform at a high level, a player must be able to produce spikes characterized by a speed of the ball that increase the defence's uncertainly. A high speed spike needs technical and muscular qualities. ... [less ▲]

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See detailImprovement of students’ motivation in a pe class. An action-research project
Cloes, Marc ULg; Viseur, C.; Motter, Pascale

in Klissouras, V.; Kellis, S.; Mouratidis, I. (Eds.) Proceedings of the 2004 Pre-Olympic Congress. Sport Science through the Ages. (2004, August)

Adolescents' motivation is a major concern of PE teachers. Many students, especially girls, are characterized by unmotivated behaviours in the gym. For two decades, quantitative research has been ... [more ▼]

Adolescents' motivation is a major concern of PE teachers. Many students, especially girls, are characterized by unmotivated behaviours in the gym. For two decades, quantitative research has been conducted to better understand the problem. More recently, some qualitative studies have been proposed. ... [less ▲]

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See detailAnalysis of anthropometric caracteristics and jumping ability in junior top level volleyball athletes. Comparison by role
Ciccarone, G.; Fontani, G.; Albert, Adelin ULg et al

Poster (2004, August)

This study is focused on the comparison of the players characteristics in youth Italian top level volleyball athletes according to the role on the game.

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See detailPE teachers’ competencies: which ones are considered as the most important and where are they acquired?
Cloes, Marc ULg; Laraki, Nadine; Piéron, Maurice

Poster (2004, August)

It is well accepted that teacher prepration is a long term process during which a large array of competencies are progressively developed. Since 2001, in the French Community of Belgium, a decree lists ... [more ▼]

It is well accepted that teacher prepration is a long term process during which a large array of competencies are progressively developed. Since 2001, in the French Community of Belgium, a decree lists the competencies that teachers should develop to achieve their role within the educational system. This study aimed to identify competencies taht PE teachers consider as important and to determine, from their point of view, in which context these competencies are developed. [less ▲]

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See detailAbnormal response to metabolic stress in schizophrenia: marker of vulnerability or acquired sensitization?
Marcelis, Machteld; Cavalier, Etienne ULg; Gielen, Jacques ULg et al

in Psychological Medicine (2004), 34(6), 1103-1111

Background. Previous work suggests that individuals with schizophrenia display an altered homovanillic acid (HVA) response to metabolic stress. The present study replicated and extended this paradigm ... [more ▼]

Background. Previous work suggests that individuals with schizophrenia display an altered homovanillic acid (HVA) response to metabolic stress. The present study replicated and extended this paradigm, including individuals with elevated genetic risk for schizophrenia. Method. Patients with psychosis (n = 50), non-psychotic first-degree relatives of patients with psychosis (n = 5 1) and controls without psychosis (n = 50) underwent, in randomized order, double-blind administration of placebo and the glucose analogue 2-deoxy-D-glucose (2DG), which induces a mild, transient clinical state of glucoprivation. Plasma HVA and cortisol were assessed twice before the start of the 2DG/placebo infusion (baseline values), as well as four times post infusion. Data were analysed using multi-level random regression techniques. Results. During the stress condition, significant increases in plasma HVA and cortisol were found. The increase in plasma HVA level during the stress condition was significantly stronger in patients than in controls, whereas this was not the case in relatives v. controls. The increase in plasma cortisol during the stress condition was significantly less in patients than controls, but no significant difference in the increase of plasma cortisol during stress was found in the comparison between relatives and controls. Conclusions. Patients with psychosis, but not their non-psychotic first-degree relatives, show an altered neurobiological response to metabolic stress, suggesting that this dysregulation is not a genetically transmitted vulnerability, but an illness-related effect, possibly reflecting acquired sensitization of neuroendocrine systems by repeated environmental stressors or repeated stimulation with agonistic drugs. [less ▲]

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See detailEquivalence of indapamide SR and enalapril on microalbuminuria reduction in hypertensive patients with type 2 diabetes: The NESTOR* study
Marre, Michel; Garcia Puig, Juan; Kokot, Franciszek et al

in Journal of Hypertension (2004), 22(8), 1613-1622

Objectives To test whether microalbuminuria in patients with type 2 diabetes and hypertension is primarily dependent on the severity of hypertension, and to compare the effectiveness of two anti ... [more ▼]

Objectives To test whether microalbuminuria in patients with type 2 diabetes and hypertension is primarily dependent on the severity of hypertension, and to compare the effectiveness of two anti hypertensive drugs with opposite effects on the renin-angiotensin system [the diuretic, indapamide sustained release (SR), and an angiotensin-converting enzyme inhibitor, enalapril] in reducing microalbuminuria. Design A multinational, multicentre, controlled, double-blind, double-dummy, randomized, two-parallel-groups study over 1 year. Methods After a 4-week placebo run-in period, 570 patients (ages 60.0 +/- 9.9 years, 64% men) with type 2 diabetes, essential hypertension [systolic blood pressure (SBP) 140-180 mmHg, and diastolic blood pressure (DBP) < 110 mmHg], and persistent microalbuminuria (20-200 mu g/min) were allocated randomly to groups to receive indapamide SR 1.5 mg (n = 284) or enalapril 10 mg (n = 286) once a day. Amlodipine, atenolol, or both were added, if necessary, to achieve the target blood pressure of 140/85 mmHg. Results There was a significant reduction in the urinary albumin: creatinine ratio. Mean reductions were 35% [95% confidence interval (Cl) 24 to 43] and 39% (95% Cl 30 to 47%) in the indapamide SR and enalapril groups, respectively. Equivalence was demonstrated between the two groups [1.08 (95% Cl 0.89 to 1.31%); P = 0.01]. The reductions in mean arterial pressure (MAP) were 16.6 +/- 9.0 mmHg for the indapamide SR group and 15.0 +/- 9.1 mmHg for the enalapril group (NS); the reduction in SBP was significantly greater (P = 0.0245) with indapamide SR. More than 50% of patients in each group required additional antihypertensive therapy, with no differences between groups. Both treatments were well tolerated. Conclusions lndapamide-SR-based therapy is equivalent to enalapril-based therapy in reducing microalbuminuria with effective blood pressure reduction in patients with hypertension and type 2 diabetes. [less ▲]

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See detailFluorinated tracers for imaging cancer with positron emission tomography
Couturier, Olivier; Luxen, André ULg; Chatal, Jean-François et al

in European Journal of Nuclear Medicine and Molecular Imaging (2004), 31(8), 1182-1206

2-[F-18]fluoro-2-deoxy-D-glucose (FDG) is currently the only fluorinated tracer used in routine clinical positron emission tomography (PET). Fluorine-18 is considered the ideal radioisotope for PET ... [more ▼]

2-[F-18]fluoro-2-deoxy-D-glucose (FDG) is currently the only fluorinated tracer used in routine clinical positron emission tomography (PET). Fluorine-18 is considered the ideal radioisotope for PET imaging owing to the low positron energy (0.64 MeV), which not only limits the dose rate to the patient but also results in a relatively short range of emission in tissue, thereby providing high-resolution images. Further, the 110-min physical half-life allows for high-yield radiosynthesis, transport from the production site to the imaging site and imaging protocols that may span hours, which permits dynamic studies and assessment of potentially fairly slow metabolic processes. The synthesis of fluorinated tracers as an alternative to FDG was initially tested using nucleophilic fluorination of the molecule, as performed when radiolabelling with iodine-124 or bromide-76. However, in addition to being long, with multiple steps, this procedure is not recommended for bioactive molecules containing reactive groups such as amine or thiol groups. Radiochemical yields are also often low. More recently, radiosynthesis from prosthetic group precursors, which allows easier radiolabelling of biomolecules, has led to the development of numerous fluorinated tracers. Given the wide availability of 18F, such tracers may well develop into important routine tracers. This article is a review of the literature concerning fluorinated radiotracers recently developed and under investigation for possible PET imaging in cancer patients. Two groups can be distinguished. The first includes "generalist" tracers, i.e. tracers amenable to use in a wide variety of tumours and indications, very similar in this respect to FDG. These are tracers for non-specific cell metabolism, such as protein synthesis, amino acid transport, nucleic acid synthesis or membrane component synthesis. The second group consists of "specific" tracers for receptor expression (i.e. oestrogens or somatostatin), cell hypoxia or bone metabolism. [less ▲]

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See detailPotentiation of tumor necrosis factor-induced NF-kappa B activation by deacetylase inhibitors is associated with a delayed cytoplasmic reappearance of I kappa B alpha (vol 23, pg 6200, 2003)
Adam, Emmanuelle; Quivy, Vincent; Bex, Françoise et al

in Molecular and Cellular Biology (2004), 24(15), 6890

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See detailThe XMM-LSS survey - First high redshift galaxy clusters: Relaxed and collapsing systems
Valtchanov, I.; Pierre, M.; Willis, J. et al

in Astronomy and Astrophysics (2004), 423(1), 75-85

We present five newly found galaxy clusters at z > 0.6 from the XMM Large-Scale Structure Survey (XMM-LSS). All five objects are extended X-ray sources in the XMM images. For three of them we have ... [more ▼]

We present five newly found galaxy clusters at z > 0.6 from the XMM Large-Scale Structure Survey (XMM-LSS). All five objects are extended X-ray sources in the XMM images. For three of them we have sufficient spectroscopically confirmed member galaxies that an estimate of the velocity dispersion is possible: XLSSC 001 at z = 0.613 and sigma(nu) = 867(-60)(+80) km s(-1), XLSSC 002 at z = 0.772 and sigma(nu) = 524(-116)(+267) km s(-1) and XLSSC 003 at z = 0.839 and sigma(V) = 780(-75)(+137) km s(-1). These three clusters have X-ray bolometric luminosities L-X similar to 1-3 x 10(44) erg s(-1) and temperatures 2-4 keV, and consequently are less massive than previously known clusters at similar redshifts, but nevertheless they follow the low redshift scaling relations between L-X, T and sigma(upsilon), within the limits of the measurement errors. One of the clusters, XLSSC 004, is detected independently as an over-density of galaxies of a colour R - z' = 1.4 that matches the redshift of the central galaxy z = 0.87, although it cannot unambiguously be confirmed by the spectroscopic observations alone. The highest redshift candidate cluster pertaining to this paper, XLSSC 005, is most likely a double cluster complex at a redshift around unity, associated with an extended X-ray source with probable substructure. [less ▲]

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See detailLimiting windstorm effects on tower by the « low drag » cable
Lilien, Jean-Louis ULg; Snegovski, Dmitri; Capelle, Thierry et al

(2004, August)

Hurricane winds affect the flow around electrical conductor in a way that it may reach the critical (Drag crisis) and postcritical states. It is thus important to introduce the cable aerodynamic drag as ... [more ▼]

Hurricane winds affect the flow around electrical conductor in a way that it may reach the critical (Drag crisis) and postcritical states. It is thus important to introduce the cable aerodynamic drag as Reynolds-dependent when calculating the response of the power transmission line under hurricane. To represent the respective wind loading on cable, the turbulent, spatially non-uniform wind model is used. In order to assess the behaviour and cyclic fatigue loads under hurricane conditions of different transmission line conductors, the time response analyses were done. Results of comparative study of the smooth cable AERO-Z and classical multistrand cable, including the percentage of load reduction offered to supporting structure, are presented. [less ▲]

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