References of "2008"
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See detailOn the Quantum Potential and Pulsating Wave Packet in the Harmonic Oscillator
Dubois, Daniel ULg

in Dubois, Daniel (Ed.) COMPUTING ANTICIPATORY SYSTEMS (2008)

A fundamental mathematical formalism related to the Quantum Potential factor, Q, is presented in this paper. The Schrödinger equation can be transformed to two equations depending on a group velocity and ... [more ▼]

A fundamental mathematical formalism related to the Quantum Potential factor, Q, is presented in this paper. The Schrödinger equation can be transformed to two equations depending on a group velocity and a density of presence of the particle. A factor, in these equations, was called “Quantum Potential” by D. Bohm and B. Hiley. In 1999, I demonstrated that this Quantum Potential, Q, can be split in two Quantum Potentials, Q1, and Q2, for which the relation, Q=Q1+Q2, holds. These two Quantum Potentials depend on a fundamental new variable, what I called a phase velocity, u, directly related to the probability density of presence of the wave-particle, given by the modulus of the wave function. This paper gives some further developments for explaining the Quantum Potential for oscillating and pulsating Gaussian wave packets in the Harmonic Oscillator. It is shown that the two Quantum Potentials play a central role in the interpretation of quantum mechanics. A breakthrough in the formalism of the Quantum Mechanics could be provoked by the physical properties of these Quantum Potentials. The probability density of presence of the oscillating and pulsating Gaussian wave packets in the Harmonic Oscillator is directly depending on the ratio Q2/Q1 of the two Quantum Potentials. In the general case, the energy of these Gaussian wave packets is not constant, but is oscillating. The energy is given by the sum of the kinetic energy, T, the potential energy, V, and the two Quantum Potentials: E=T+V+Q1+Q2. For some conditions, given in the paper, the energy can be a constant. The first remarkable result is the fact that the first Quantum Potential, Q1, is related to the ground state energy, E0, of the Quantum Harmonic Oscillator: Q1=[barred aitch]omega/2=E0. The second result is related to the property of the second Quantum Potential, Q2, which plays the role of an anti-potential, Q2=-V(x), where V is the harmonic oscillator potential. This Quantum Potential counter-balances the harmonic oscillator potential, so there is no more harmonic potential in the quantum harmonic oscillator. It remains just a constant potential given by the first Quantum Potential, Q1. The interpretation is as follows: a quantum system can annihilate a classical potential, and so gives rise to a quantum tunnelling, which violates the principles of Classical Mechanics. [less ▲]

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See detailQuality of life after abdominal aortic aneurysm repair: similar long-term results with endovascular and open techniques.
Kolh, Philippe ULg

in European Journal of Vascular and Endovascular Surgery (2008), 36(3), 290-1

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See detailThree-stage autoignition of gasoline in an HCCI engine: An experimental and chemical kinetic modeling investigation
Machrafi, Hatim ULg; Cavadias, Simeon

in Combustion & Flame (2008), 155(4), 557-570

The alternative HCCI combustion mode presents a possible means for decreasing the Pollution with respect to conventional gasoline or diesel engines, while maintaining the efficiency of a diesel engine or ... [more ▼]

The alternative HCCI combustion mode presents a possible means for decreasing the Pollution with respect to conventional gasoline or diesel engines, while maintaining the efficiency of a diesel engine or even increasing it. This paper investigates the possibility Of using gasoline in an HCCI engine and analyzes the autoignition of gasoline in such an engine. The compression ratio that has been used is 13.5, keeping the inlet temperature at 70 degrees C, varying the equivalence ratio from 0.3 to 0.54, and the EGR (represented by N-2) ratio from 0 to 37 vol%. For comparison, a PRF95 and a Surrogate containing 11 vol% n-heptane, 59 vol% iso-octane, and 30 vol% toluene are used. A previously validated kinetic surrogate mechanism is Used to analyze the experiments and to yield possible explanations to kinetic phenomena. From this work, it seems quite possible to use the high octane-rated gasoline for autoignition purposes, even Under lean inlet conditions. Furthermore, it appeared that gasoline and its Surrogate, unlike PRF95, show a three-stage autoignition. Since the PRF95 does not contain toluene, it is Suggested by the Kinetic mechanism that the benzyl radical, issued from toluene, causes this so-defined "obstructed preignition" and delaying thereby the final ignition for gasoline and its surrogate. The results of the kinetic mechanism supporting this explanation are shown in this paper. (C) 2008 The Combustion Institute. Published by Elsevier Inc. All rights reserved. [less ▲]

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See detailDetermination of plant height for weed detection in stereoscopic images
Piron, Alexis ULg; Leemans, Vincent ULg; Kleynen, Olivier et al

in AGENG 2008 Conference - Agricultural & Biosystems Engineering for a Sustainable World (2008)

The aim of this study was twofold. The first goal was to acquire high accuracy stereoscopic images of small-scale field scenes, the second to examine the potential of plant height as a discriminant factor ... [more ▼]

The aim of this study was twofold. The first goal was to acquire high accuracy stereoscopic images of small-scale field scenes, the second to examine the potential of plant height as a discriminant factor between crop and weed, within carrot rows. Emphasis was put on how to determine actual plant height taking into account the variable distance from camera to ground and ground irregularities for in-field measurements. Multispectral stereoscopic images were taken over a period of 19 days starting one week after crop emergence and seven weed species were considered. Images were acquired with a mobile vision system consisting in a filter wheel based multispectral camera and a video projector. The stereoscopy technique used belonged to the coded structured light family. The stereoscopic acquisition method yielded good results despite the numerous stereoscopic difficulties exhibited by the scenes. A plant height parameter as opposed to distance from camera to plant pixels gave better results for classification (classification accuracy of up [less ▲]

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See detailSurvival of yolk’s immunoglobulins directed against Salmonella Enteritidis and Salmonella Typhimurium in the gastro-intestinal tract of the broiler chicken
Marcq, Christopher ULg; Graide, Virginie; Beckers, Yves ULg et al

in Proceedings of the Thirteenth Conference on Food Microbiology (2008)

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See detailPersistence of an intact endometrial matrix and vessels structure in women exposed to VA-2914, a selective progesterone receptor modulator.
Ravet, Stéphanie ULg; Munaut, Carine ULg; Blacher, Silvia ULg et al

in Journal of Clinical Endocrinology and Metabolism (2008), 93(11), 4525-31

Background: VA-2914 is a selective progesterone receptor modulator with potential contraceptive activity that induces amenorrhea, whereas progestins cause endometrial spotting and bleeding. This abnormal ... [more ▼]

Background: VA-2914 is a selective progesterone receptor modulator with potential contraceptive activity that induces amenorrhea, whereas progestins cause endometrial spotting and bleeding. This abnormal bleeding due to progestins is a consequence of focal stromal proteolysis by an increase in naked vessel size and density. Objective: Our objective was to quantify the effects of VA-2914 on endometrial vascularization, fibrillar matrix, and vascular endothelial growth factor (VEGF)-A expression in endometrial biopsies from 41 women before and after 12 wk daily treatment with a placebo, or 2.5, 5, or 10 mg VA-2914. Methods: Collagen fibrillar network was stained by silver impregnation. Vessel area, density, and structure were quantified with a computer-assisted image analysis system after double immunostaining using an anti-von Willebrand factor (endothelial cells) and an anti- smooth muscle actin (vascular smooth muscle cells) marker antibody. VEGF-A mRNAs were quantified by RT-PCR and localized by immunohistochemistry. Results: The endometrial vessels, collagen network, and mRNA levels of VEGF-A were identical during the luteal phase at baseline and in VA-2914 treated women. VEGF-A distribution was unchanged. Conclusions: VA-2914 does not alter the endometrial matrix and cells, and does not modify the endometrial vessel morphology as compared with baseline biopsies. [less ▲]

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See detailBovine colostrum as a natural growth promoter for newly weaned piglets: a review.
Boudry, Christelle ULg; Dehoux, Jean-Paul; Portetelle, Daniel ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (2008), 12(2), 157-170

The aim of this review is to present the potential of bovine colostrum as growth promoter in piglet-weaner diet. The consequences of weaning on the growth performance, on the gastro-intestinal tract and ... [more ▼]

The aim of this review is to present the potential of bovine colostrum as growth promoter in piglet-weaner diet. The consequences of weaning on the growth performance, on the gastro-intestinal tract and on the metabolic and endocrine systems of the piglet are described in the first part of this review. The second part is dedicated to the bovine colostrum, with a description of the actions due to its main growth promoters and antimicrobial factors. Finally, the reported effects of bovine specific components or bovine fractions on the growth performance and on the structure and function of the gastro-intestinal tract of piglets in the early postweaning period are presented. They show clearly the potential of bovine colostrum to reduce the growth-check related to the weaning of the piglet. [less ▲]

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See detailModel of Irrigation Development for Floodplain of the Tonle Sap Great Lake
someth, Paradis; Kubo, n; Ly, Sarann ULg et al

Poster (2008)

Rice is a staple crop in Cambodia. To meet the large requirement of rice consumption due to rapid increased population and to boost the economy, the rice production in this country needs to be enhanced ... [more ▼]

Rice is a staple crop in Cambodia. To meet the large requirement of rice consumption due to rapid increased population and to boost the economy, the rice production in this country needs to be enhanced. The Tonle Sap Great Lake of Cambodia has huge floodplain suitable for large amount for rice production and potential water resources for rice-based farming system. Due to large variation of water level of the lake, some areas around the lake are flooded in wet season and shortage of water in dry season. Studies to exploit the flood and the water rsources of the lake and its tributaries have not been well conducted yet. The West Baray and Batheay irrigation systems are located in the floodplain of the Tonle Sap Great Lake and the Mekong River. In this research, the irrigation systems are studied as model sites for future development of the floodplain of the Tonle Sap Great Lake. [less ▲]

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See detailGuideline on antiplatelet and anticoagulation management in cardiac surgery.
Dunning, Joel; Versteegh, Michel; Fabbri, Alessandro et al

in European Journal of Cardio - Thoracic Surgery (2008), 34(1), 73-92

This document presents a professional view of evidence-based recommendations around the issues of antiplatelet and anticoagulation management in cardiac surgery. It was prepared by the Audit and ... [more ▼]

This document presents a professional view of evidence-based recommendations around the issues of antiplatelet and anticoagulation management in cardiac surgery. It was prepared by the Audit and Guidelines Committee of the European Association for Cardio-Thoracic Surgery (EACTS). We review the following topics: evidence for aspirin, clopidogrel and warfarin cessation prior to cardiac surgery; perioperative interventions to reduce bleeding including the use of aprotinin and tranexamic acid; the use of thromboelastography to guide blood product usage; protamine reversal of heparin; the use of factor VIIa to control severe bleeding; anticoagulation after mechanical, tissue valve replacement and mitral valve repair; the use of antiplatelets and clopidogrel after cardiac surgery to improve graft patency and reduce thromboembolic complications and thromboprophylaxis in the postoperative period. This guideline is subject to continuous informal review, and when new evidence becomes available. The formal review date will be at 5 years from publication (September 2013). [less ▲]

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See detailÉcologisation : Objets et concepts intermédiaires
Melard, François ULg

Book published by P.I.E. Peter-Lang (2008)

Les questions environnementales contemporaines sont éminemment complexes et réticulaires. La manière privilégiée de les aborder consiste à s'intéresser aux moyens matériels et conceptuels employés par les ... [more ▼]

Les questions environnementales contemporaines sont éminemment complexes et réticulaires. La manière privilégiée de les aborder consiste à s'intéresser aux moyens matériels et conceptuels employés par les acteurs eux-mêmes (gestionnaires, experts, riverains, etc.) pour diagnostiquer, pour se coordonner et pour agir. Nous verrons ainsi comment des cartes (d'épandage ou d'un réseau écologique), des schémas (d'aménagement d'un site classé), des fiches projets (d'une politique de conservation de la nature), un tableau (de mise en correspondance des pratiques de consommation et de leurs impacts sur l'environnement), un diagramme (dans le milieu de la production du boeuf bio) ou encore des concepts (de classement de zones humides ou de gestion d'un lac) sont autant de repères à la fois pour la description par l'observateur de ce qui est en construction dans le travail de concertation, mais surtout pour l'action même des acteurs engagés. Nous les appellerons, avec d'autres, des objets et concepts intermédiaires. Ces entités techniques - quelques fois ésotériques - suivies dans leurs élaborations ou dans leur détournement renseignent sur des représentations des milieux et des ressources naturels et sur leurs transformations et peuvent être de véritables médiatrices dans l'émergence de dynamiques collectives originales. Elles constituent le fil d'Ariane par lequel l'environnement entre en société. Contenu : François Mélard : Introduction - François Mélard : L'héritage des études sociales de l'objet dans l'action - Marc Mormont/Bernard Hubert : De l'environnement au développement durable. Le rôle des médiateurs - Catherine Mougenot/Pierre M. Stassart : Les objets éphémères du développement durable. Un mécanisme de « représentation/transformation » - Marc Mormont : La carte comme schéma prospectif négocié - Hélène Brives : Les appuis matériels de l'action collective. La construction d'une carte communale des terres d'épandage - Hélène Brives/Marc Mormont : Les médiations de l'action collective « environnementale » - Isabelle Haynes/Catherine Mougenot : La socialisation des politiques environnementales par des objets intermédiaires - Régine Teulier/Bernard Hubert : Des concepts intermédiaires pour la conception collective. Les situations d'action collective avec acteurs hétérogènes - Patrick Steyaert : Des concepts intermédiaires producteurs de sens pour la gestion environnementale. Une étude de cas sur les zones humides côtières en France - François Mélard : Conclusion. [less ▲]

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See detailProtein synthesis and folding is a rate limiting step for bacterial growth at low temperatures.
Piette, Florence; D'Amico, Salvino; Leprince, Pierre ULg et al

Poster (2008)

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See detailMultiscale modeling of equal channel angular extruded aluminium with strain gradient crystal plasticity and phenomenological models
Duchene, Laurent ULg; Geers, M. G. D.; Brekelmans, W. A. M. et al

in Rollett, A. (Ed.) Proceedings of the 15th International Conference on the Texture of Materials (ICOTOM-15) (2008)

The Equal Channel Angular Extrusion process is used to modify the microstructure of an AA1050 aluminum alloy in order to produce an ultra fine grained material. Due to the severe plastic deformation ... [more ▼]

The Equal Channel Angular Extrusion process is used to modify the microstructure of an AA1050 aluminum alloy in order to produce an ultra fine grained material. Due to the severe plastic deformation undergone by the material during the ECAE process, the subsequent behavior of the material is non-conventional and difficult to model with classical constitutive laws (e.g. ECAE aluminum presents a large initial back-stress which must be adequately incorporated in the model). In this study, the evolution of the back-stress during the ECAE process is analyzed. Two different numerical models were investigated in this respect. The first one is a single crystal strain gradient plasticity model based on dislocation densities. The second model is the Teodosiu and Hu’s hardening model, which is a microstructuraly based phenomenological model at the macroscale. The results provided by the two models are obviously distinct. Nevertheless, some common trends can be pointed out, among which the amplitude of the back-stress that is similar. In agreement with the cyclic deformation mode of the studied route C ECAE process, the evolution of the predicted back-stress is also cyclic in both models. [less ▲]

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See detailEtude de la variabilité de la qualité de la viande de porc par analyse en composantes principales
Leroy, Bernadette ULg; Etienne, Grégory; China, Bernard et al

in Sciences des Aliments (2008), 28(6), 451-468

Study of the variability of pork quality by Principal Component Analysis (PCA) Principal component analysis (PCA) was performed to study the relationships between technological, organoleptic ... [more ▼]

Study of the variability of pork quality by Principal Component Analysis (PCA) Principal component analysis (PCA) was performed to study the relationships between technological, organoleptic, microbiological and zootechnic variables, measured on 264 pigs belonging to different Belgian production systems. The four first principal components explained 63 % of the total variability. The variables such as the pH, the electrical conductivity, the brightness and the color of meat presented the best correlation with the first principal component whereas the variables such as the E. coli Count and the Total Viable Count measured on the carcass, the hot carcass weight and the cooking loss of meat presented the best correlation with the second principal component. The first principal component was defined as an axis of technological and organoleptic quality whereas the second was defined as a microbiological axis. PCA allowed to differentiate two groups in terms of technological and organoleptic properties. A group including samples belonged to the first quality production chain and a part of samples belonged to the second was separated from the principal group by a lower pH, measured 45 minutes post mortem, and a paler meat. [less ▲]

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See detailShear strength of unsaturated soil and its influence on slope stability
Tomboy, Olivier; Whenham, Valérie; De Vos, Monika et al

in 1st European Conference on Unsaturated Soils (2008)

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See detailRapid, postmortem 9.4 T MRI of spinal cord injury: correlation with histology and survival times.
Scholtes, Félix ULg; Phan-Ba, Rémy ULg; Theunissen, Evi et al

in Journal of Neuroscience Methods (2008), 174(2), 157-67

High field magnetic resonance imaging (MRI) has been increasingly used to assess experimental spinal cord injury (SCI). In the present investigation, after partial spinal cord injury and excision of the ... [more ▼]

High field magnetic resonance imaging (MRI) has been increasingly used to assess experimental spinal cord injury (SCI). In the present investigation, after partial spinal cord injury and excision of the whole spine, pathological changes of the spinal cord were studied in spinal cord-spine blocks, from the acute to the chronic state (24 h to 5 months). Using proton density (PD) weighted imaging parameters at a magnetic field strength of 9.4 tesla (T), acquisition times ranging from <1 to 10 h per specimen were used. High in-plane pixel resolution (68 and 38 microm, respectively) was obtained, as well as high signal-to-noise ratio (SNR), which is important for optimal contrast settings. The quality of the resulting MR images was demonstrated by comparison with histology. The cord and the lesion were shown in their anatomical surroundings, detecting cord swelling in the acute phase (24 h to 1 week) and cord atrophy at the chronic stage. Haemorrhage was detected as hypo-intense signal. Oedema, necrosis and scarring were hyper-intense but could not be distinguished. Histology confirmed that the anatomical delimitation of the lesion extent by MRI was precise, both with high and moderate resolution. The present investigation thus demonstrates the precision of spinal cord MRI at different survival delays after compressive partial SCI and establishes efficient imaging parameters for postmortem PD MRI. [less ▲]

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See detailValidation of a nonaqueous capillary electrophoretic method for the enantiomeric purity determination of R-flurbiprofen using a single-isomer amino cyclodextrin derivative
Rousseau, Anne ULg; Chiap, Patrice ULg; Ivanyi, Robert et al

in Journal of Chromatography. A (2008), 1204(2), 219-225

Nonaqueous capillary electrophoresis (NACE) was successfully applied to the enantiomeric purity determination of R-flurbiprofen using 6-monodeoxy-6-mono(2-hydroxy)propylamino-beta-cyclodextrin (IPA-beta ... [more ▼]

Nonaqueous capillary electrophoresis (NACE) was successfully applied to the enantiomeric purity determination of R-flurbiprofen using 6-monodeoxy-6-mono(2-hydroxy)propylamino-beta-cyclodextrin (IPA-beta-CD) as chiral selector. The nonaqueous BGE was made up of 20 mM IPA-beta-CD, 20 mM ammonium camphorsulfortate and 40 mM ammonium acetate in methanol. Flufenamic acid was selected as internal standard. The CE method was carefully optimized in order to prevent the adsorption of the cationic CD onto the capillary wall, and therefore, to avoid loss of peak efficiency and enantioresolution. To achieve this goal, the addition of ammonium camphorsulfonate was found to be necessary. In the selected conditions, the determination of 0.1% of S-flurbiprofen in R-flurbiprofen could be performed using the method of standard additions. The NACE method was then fully validated by applying a novel strategy using accuracy profiles. (c) 2008 Elsevier B.V. All rights reserved. [less ▲]

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