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See detailEtat de l'art de l'holographie dynamique : systèmes appliqués à la métrologie et au contrôle non destructif
Georges, Marc ULg; Thizy, Cédric ULg; Ryhon, Sébastien et al

Conference (2004, January)

Dans ce papier, nous présentons le résultat de plus de dix années de recherche et développement au Centre Spatial de Liège (CSL) concernant une caméra holographique (utilisant la technique de l ... [more ▼]

Dans ce papier, nous présentons le résultat de plus de dix années de recherche et développement au Centre Spatial de Liège (CSL) concernant une caméra holographique (utilisant la technique de l'interférométrie holographique) capable d'effectuer des mesures, sans contact et sur un grand champ, de déplacements dans la gamme des microns et submicrons. Les principales applications montrées sont la recherche de défauts, l'identification de modes de vibration et la métrologie de déplacements. [less ▲]

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See detailDynamic holography for fringerprints detection
Lemaire, Philippe; Georges, Marc ULg

Conference (2004, January)

Fingerprint detection method is generally based on optical contrast technique. We present a special case of holographic interferometry use, that envisages fingerprint visualisation on base of their relief ... [more ▼]

Fingerprint detection method is generally based on optical contrast technique. We present a special case of holographic interferometry use, that envisages fingerprint visualisation on base of their relief. Background of the algorithm is first presented and discussed. We finish by practical application. [less ▲]

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See detailGranular size segregation in underwater sand ripples
Rousseaux, G.; Caps, Hervé ULg; Wesfreid, J. E.

in European Physical Journal E -- Soft Matter (2004), 13(2), 213-219

We report an experimental study of a binary sand bed under an oscillating water flow. The formation and evolution of ripples is observed. The appearance of a granular segregation is shown to strongly ... [more ▼]

We report an experimental study of a binary sand bed under an oscillating water flow. The formation and evolution of ripples is observed. The appearance of a granular segregation is shown to strongly depend on the sand bed preparation. The initial wavelength of the mixture is measured. In the final steady state, a segregation in volume is observed instead of a segregation at the surface as reported before. The correlation between this phenomenon and the fluid flow is emphasised. Finally, different "exotic" patterns and their geophysical implications are presented. [less ▲]

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See detailEffects of silicon addition on the electrical and magnetic properties of copper-doped (La,Ca)MnO3 compounds
Vertruyen, Bénédicte ULg; Rulmont, André ULg; Cloots, Rudi ULg et al

in Journal of Magnetism and Magnetic Materials (2004), 268(3), 364-373

In this paper we report about the electrical properties of La0.7Ca0.3MnO3 compounds substituted by copper on the manganese site and/or deliberately contaminated by SiO2 in the reactant mixture. Several ... [more ▼]

In this paper we report about the electrical properties of La0.7Ca0.3MnO3 compounds substituted by copper on the manganese site and/or deliberately contaminated by SiO2 in the reactant mixture. Several phenomena have been observed and discussed. SiO2 addition leads to the formation of an apatite-like secondary phase that affects the electrical conduction through the percolation of the charge carriers. On the other hand, depending on the relative amounts of copper and silicon, the temperature dependence of the electrical resistivity can be noticeably modified: our results enable us to compare the effects of crystallographic vacancies on the A and B sites of the perovskite with the influence of the copper ions substituted on the manganese site. The most original result occurs for the compounds with a small ratio Si/Cu, which display double-peaked resistivity vs. temperature curves. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailFour extended formulations of the corner polyhedron
Louveaux, Quentin ULg

Conference (2004, January)

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See detailActualites en anesthésie-réanimation en chirurgie cardiaque adulte
Roediger, Laurence ULg; Larbuisson, Robert ULg; Senard, Marc ULg et al

in Revue Médicale de Liège (2004), 59(1), 35-45

Anesthetic techniques and treatment of cardiac surgery patients have considerably evolved over the past twenty years. The demand for cardiac surgical procedures is increasing. This demand coincides with a ... [more ▼]

Anesthetic techniques and treatment of cardiac surgery patients have considerably evolved over the past twenty years. The demand for cardiac surgical procedures is increasing. This demand coincides with a change in the profile of patients presenting for surgery, requiring modification in perioperative management strategies. Several new anesthetics, related drugs, and technologies have become available in recent years that inevitably have made new approaches with patient management possible. In parallel to these new developments, there have appeared real opportunities to apply novel physiologic and pharmacologic concepts that may redefine our clinical practice. Fast-tracking, which emphasizes the major role of anesthetic management in postoperative outcome, is one such line of investigation. Fast-tracking was first introduced in an attempt to decrease the time to tracheal extubation and reduce expensive time in intensive care unit areas. Large doses of opioids have been clearly identified as a factor in delaying weaning from mechanical ventilatory support after cardiac surgery. Thus, early investigations emphasized the importance of limiting the dose of potent opioid analgesics during the intraoperative period to achieve early recovery. Supplementation with hypnotic drugs allows reduction of the opioid dose, enabling earlier extubation without compromising hemodynamic stability. Fast track cardiac anesthesia (FTCA) is becoming an accepted practice for perioperative management of cardiac surgical patients. FTCA is a key component to successful conduction of fast-track cardiac surgery. Also, analgesia management in cardiac surgery is becoming more important with the establishment of minimally invasive direct coronary artery bypass surgery and fast track management of conventional cardiac surgery patients. [less ▲]

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See detailDegenerative musculoskeletal disease
Ethgen, Olivier ULg; Reginster, Jean-Yves ULg

in Annals of the Rheumatic Diseases (2004), 63(1), 1-3

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See detailValidation and comparative evaluation of the osteoporosis self-assessment tool (OST) in a Caucasian population from Belgium
Richy, F.; Gourlay, M.; Ross, P. D. et al

in QJM : Monthly Journal of the Association of Physicians (2004), 97(1), 39-46

BACKGROUND: Risk indices have been developed to identify women at risk of low bone mineral density (BMD) who should undergo BMD testing. Aim: To compare the performance of four risk indices in White ... [more ▼]

BACKGROUND: Risk indices have been developed to identify women at risk of low bone mineral density (BMD) who should undergo BMD testing. Aim: To compare the performance of four risk indices in White ambulatory women in Belgium. DESIGN: Epidemiological cross-sectional study. METHODS: Records were analysed for 4035 postmenopausal White women without Paget's disease or advanced osteoarthritis, seen at an out-patient osteoporosis centre between January 1996 and September 1999. Osteoporosis risk index scores were compared to bone density T-scores. The ability of each risk index to identify women with low BMD (T-score < -2.0) or osteoporosis (T < -2.5) was evaluated. RESULTS: Using an Osteoporosis Self-Assessment Tool (OST) score <2 to recommend DXA referral, sensitivity ranged from 85% at the lumbar spine to 97% at the total hip to detect BMD T-scores of <or= -2.5, and specificity ranged from 34% at the total hip to 37% at the femoral neck and lumbar spine. The negative predictive value was high at all skeletal sites (89-99%), demonstrating the usefulness of the OST to identify patients who have normal BMD and should not receive DXA testing. All risk indices performed similarly, although the OST had somewhat better sensitivity and somewhat lower specificity than the other indices at the cut-offs evaluated. Among the 11-12% of women who were classified as highest risk using OST or the Osteoporosis Index of Risk (OSIRIS), 81-85% had low bone mass and 68-74% had osteoporosis. DISCUSSION: The performance of these risk indices among women in Belgium was similar to that reported earlier for other samples in Asian countries, the US, and the Netherlands. The OST and other risk indices are effective and efficient tools to help target high-risk women for DXA testing. [less ▲]

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See detailChrysopentamine, an antiplasmodial anhydronium base from Strychnos usambarensis leaves
Frederich, Michel ULg; Cristino, Assunção; Choi, Young Hae et al

in Planta Medica (2004), 70(1), 72-76

A new derivative of strychnopentamine was isolated from the leaves of Strychnos usambarensis. This compound, named chrysopentamine, was identified by detailed spectroscopic methods (UV, IR, HR-ESI-MS, 1D ... [more ▼]

A new derivative of strychnopentamine was isolated from the leaves of Strychnos usambarensis. This compound, named chrysopentamine, was identified by detailed spectroscopic methods (UV, IR, HR-ESI-MS, 1D and 2D NMR). Chrysopentamine presented an original hydroxy substitution on C-14 and an aromatization of the ring D of strychnopentamine leading to anhydronium base proper-ties and exhibited strong antiplasmodial properties (IC50 less than 1 muM). [less ▲]

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See detailBases d'une croissance du transport intermodal en Belgique
Marchal, Jean ULg; Macharis, Cathy; Lundoluka, Ferdinand et al

Report (2004)

The project "Bases of a growth of intermodal transport in Belgium: the search of “missing links” "is a coherent whole of tasks carried out by two transport research centers, one working within the ... [more ▼]

The project "Bases of a growth of intermodal transport in Belgium: the search of “missing links” "is a coherent whole of tasks carried out by two transport research centers, one working within the university of Liege (Ulg) and the other working within the Vrije Universiteit Brussel (VUB). The two research centers constituted a common team in order to work together on a certain number of topics concerning the transportation in general. This research project is based on various former research projects carried out by the two research centers. These previous researches led to the conclusion that the practitioners as well as the public decision-makers should concentrate on specific elements to stimulate a better growth of the intermodal transport in Belgium. The team has identified four elements which constitute real "missing links", not enough taken into account by the public policy and the administrators of the intermodal transport. These four elements are: 1. A tool to follow the prices of the intermodal transport 2. An analysis of the most critical value added services that should be supplied by the intermodal terminal operators 3. A series of directives to optimize the packaging of the goods to stimulate the intermodal transport 4. An instrument of follow-up of "modal scan" These elements are analysed and each of them constitute an entire module of this report. [less ▲]

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See detailPhysionomie et composition des zones riveraines des cours d'eau de Wallonie
Mouchet, F.; Debruxelles, N.; Graux, G. et al

in Forêt Wallonne (2004), (68), 2-7

La physionomie des abords d’un cours d’eau est très variable, tantôt forestière, tantôt traversant les champs ou totalement anthropisée. Dans quelle proportion retrouve-t-on chaque type de milieu ? Quels ... [more ▼]

La physionomie des abords d’un cours d’eau est très variable, tantôt forestière, tantôt traversant les champs ou totalement anthropisée. Dans quelle proportion retrouve-t-on chaque type de milieu ? Quels sont les arbres qui forment les cordons rivulaires ? Ce sont des résultats maintenant disponibles à l’échelle de la Région wallonne suite à la mise sur pied d’un inventaire des zones riveraines de nos cours d’eau. Ceci a été rendu possible par la collaboration du personnel de deux conventions I- II passées entre la Faculté universitaire des Sciences agronomiques de Gembloux et la Direction des Cours d’Eau non Navigables (MRW, DGRNE). [less ▲]

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See detailLa sylviculture d'arbres "objectif" ou d'arbres de place (cahier technique n°27)
Baar, F.; Snoeck, B.; Balleux, P. et al

in Forêt Wallonne (2004), (68), 2-8

Ce cahier technique se présente en deux parties. La première est constituée du dossier remis à l’ensemble des agents de l’administration forestière lors des journées de formation. La seconde présente les ... [more ▼]

Ce cahier technique se présente en deux parties. La première est constituée du dossier remis à l’ensemble des agents de l’administration forestière lors des journées de formation. La seconde présente les exercices de la formation ainsi que les résultats obtenus. Complémentaires, ces deux parties cherchent à confronter la théorie et la pratique, l’exposé académique et les discussions à bâtons rompus. Cette formation a été délivrée, dans le contexte de l’accord cadre de recherche forestière liant l’Université Catholique de Louvain, la Faculté universitaire des Sciences agronomiques de Gembloux et l’asbl Forêt Wallonne, à l’ensemble des agents forestiers des cantonnements de la Région wallonne. [less ▲]

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See detailRiemannian geometry of Grassmann manifolds with a view on algorithmic computation
Absil, P.-A.; Mahony, R.; Sepulchre, Rodolphe ULg

in Acta Applicandae Mathematicae (2004), 80(2), 199-220

We give simple formulas for the canonical metric, gradient, Lie derivative, Riemannian connection, parallel translation, geodesics and distance on the Grassmann manifold of p-planes in R-n. In these ... [more ▼]

We give simple formulas for the canonical metric, gradient, Lie derivative, Riemannian connection, parallel translation, geodesics and distance on the Grassmann manifold of p-planes in R-n. In these formulas, p-planes are represented as the column space of n x p matrices. The Newton method on abstract Riemannian manifolds proposed by Smith is made explicit on the Grassmann manifold. Two applications - computing an invariant subspace of a matrix and the mean of subspaces - are worked out. [less ▲]

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See detailCharacteristics of peri-urban dairy herds of Bobo-Dioulasso (Burkina Faso)
Sidibe, M.; Boly, Hamidou ULg; Lakouetene, T. et al

in Tropical Animal Health and Production (2004), 36(1), 95-100

Peri-urban dairy cattle farms within 50 km of Bobo-Dioulasso were studied to assess herd type, disease incidence, management, feeding and breeding strategy. Out of 417 cattle farmers, 42% had dairy ... [more ▼]

Peri-urban dairy cattle farms within 50 km of Bobo-Dioulasso were studied to assess herd type, disease incidence, management, feeding and breeding strategy. Out of 417 cattle farmers, 42% had dairy objectives and were studied. Among these peri-urban dairy farmers, 60% were settled, 36% semi-settled, and 4% transhumant. In total, they held 4558 dairy cows, of which 32% lactated during the study. The prevalence of mastitis (55%) increased (p<0.05) with herd size. Advanced strategies for supplementary feeding and breeding were most frequent in small herds (< 30 cattle). None of the large herds ( > 60 cattle) had advanced breeding strategies. Bulls and cows were culled at younger ages in herds with better breeding strategy. Overall, this resulted in higher individual milk offtake in small herds (2.46 L/day) compared with large herds (1.25 L/day). Pure breeds were rarely used, and the presence of Bos taurus baoule naturally selected for trypanotolerance was low. The prevalence of trypanosomosis (40%) in herds dominated by Bos indicus zebu and Mere (Zebu x Baoule) is an argument for maintenance of biodiversity and selection of Baoule for milk production. [less ▲]

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See detailb - tau Yukawa nonunification in supersymmetric SU(5) with an Abelian flavor symmetry
Aristizabal Sierra, Diego ULg; Nardi, Enrico

in Physics Letters B (2004), 578

We present a supersymmetric SU(5) x U(1)H model, free from gauge anomalies, where the Abelian factor U(1)H, introduced to account for the hierarchy of fermion masses and mixings, is broken by the same ... [more ▼]

We present a supersymmetric SU(5) x U(1)H model, free from gauge anomalies, where the Abelian factor U(1)H, introduced to account for the hierarchy of fermion masses and mixings, is broken by the same adjoint representations of SU(5) that also break the GUT symmetry. The model predicts approximate, but never exact, bottom-τ Yukawa unification. The deviations are related to group theoretical coefficients and can naturally be at the level of 10%-20%. [less ▲]

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See detailLes troubles phonologiques : cadre théorique, diagnostic et traitement
Schelstraete, Marie -Anne; Maillart, Christelle ULg

in Schelstraete, Marie-Anne; Noel, Marie-Pascale (Eds.) Les troubles du langage et du calcul chez l’enfant. (2004)

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See detailL’évaluation des troubles phonologiques : illustration de la démarche linguistique par la présentation d’épreuves qualitatives.
Maillart, Christelle ULg; Schelstraete, Marie-Anne

in Schelstraete, Marie-Anne; Noël, Marie-Pascale (Eds.) Les troubles du langage et du calcul chez l’enfant. (2004)

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See detailL'insertion internationale des petits pays. Le cas de l'Uruguay: de l'indépendance au nouveau régionalisme
Santander, Sébastian ULg; Bizzozero, Lincoln

in Santander, Sébastian (Ed.) Globalisation, gouvernance et logiques régionales dans les Amériques (2004)

L'article se penche sur les pays à faible poids économique et politique sur l'arène internationale. Il analyse la stratégie d'intégration régionale sud-américaine de l'Uruguay qui est entouré par deux ... [more ▼]

L'article se penche sur les pays à faible poids économique et politique sur l'arène internationale. Il analyse la stratégie d'intégration régionale sud-américaine de l'Uruguay qui est entouré par deux pays puissants que sont l'Argentine et le Brésil. [less ▲]

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