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See detailDeregulated expression of pro-survival and pro-apoptotic p53-dependent genes upon Elongator deficiency in colon cancer cells.
Cornez, Isabelle ULg; Creppe, Catherine ULg; Gillard, Magali ULg et al

in Biochemical Pharmacology (2008), 75

Elongator, a multi-subunit complex assembled by the IkappaB kinase-associated protein (IKAP)/hELP1 scaffold protein is involved in transcriptional elongation in the nucleus as well as in tRNA ... [more ▼]

Elongator, a multi-subunit complex assembled by the IkappaB kinase-associated protein (IKAP)/hELP1 scaffold protein is involved in transcriptional elongation in the nucleus as well as in tRNA modifications in the cytoplasm. However, the biological processes regulated by Elongator in human cells only start to be elucidated. Here we demonstrate that IKAP/hELP1 depleted colon cancer-derived cells show enhanced basal expression of some but not all pro-apoptotic p53-dependent genes such as BAX. Moreover, Elongator deficiency causes increased basal and daunomycin-induced expression of the pro-survival serum- and glucocorticoid-induced protein kinase (SGK) gene through a p53-dependent pathway. Thus, our data collectively demonstrate that Elongator deficiency triggers the activation of p53-dependent genes harbouring opposite functions with respect to apoptosis. [less ▲]

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See detailLa libéralisation du secteur postal
Gautier, Axel ULg

in Regards économiques (2008), 60

En 2011, le marché postal sera entièrement libéralisé. Le service universel sera-t-il maintenu ? Comment sera-t-il financé ? Dans cet article, nous abordons la question du financement du service universel ... [more ▼]

En 2011, le marché postal sera entièrement libéralisé. Le service universel sera-t-il maintenu ? Comment sera-t-il financé ? Dans cet article, nous abordons la question du financement du service universel postal dans un environnement concurrentiel. La Commission européenne propose plusieurs pistes, les Etats Membres doivent maintenant choisir la solution la plus appropriée à leur marché. [less ▲]

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See detailAccess Pricing and Entry in the Postal Sector
Bloch, Francis; Gautier, Axel ULg

in Review of Network Economics (2008), 7(2), 207-230

In a fully liberalized postal market, two business models will be possible for a new postal operator: (1) access: where the firm performs the upstream operations and uses the incumbent's network for final ... [more ▼]

In a fully liberalized postal market, two business models will be possible for a new postal operator: (1) access: where the firm performs the upstream operations and uses the incumbent's network for final delivery and (2) bypass where the competing firm controls the entire supply chain and delivers mails with its own network. The choice between access and bypass depends on the entrant's delivery cost relative to the access price. In this paper, we derive welfare maximizing prices for the incumbent operator and we show how these prices should be re-balanced when the entry method is considered as endogenous. [less ▲]

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See detailSteel and composite building frames: sway response under conventional loading and developmet of membrane effects in beams further to an exceptional action
Demonceau, Jean-François ULg

Doctoral thesis (2008)

The present thesis is dedicated to the study of the behaviour of steel and composite steel-concrete building frames with a particular attention paid to the beam-to-column joint behaviour. Two main topics ... [more ▼]

The present thesis is dedicated to the study of the behaviour of steel and composite steel-concrete building frames with a particular attention paid to the beam-to-column joint behaviour. Two main topics are investigated herein: the behaviour of sway building frames subjected to “conventional” loadings and the development of the membrane forces in structural beams further to the loss of a column. Regarding the first topic, the main objective is to propose a simplified analytical method to predict the ultimate load factor of composite sway building frames, a case not yet covered by the actual codes and standards. To achieve this goal, the behaviour of composite joints subjected to bending moments is first studied through experimental and analytical investigations; indeed, the joints are key elements influencing the response of sway frames. Through these investigations, a new collapse mode is identified for single-sided composite joints subjected to hogging moments and an analytical method is proposed and validated to introduce this new collapse mode in the joint design. In addition, an analytical method is also proposed and validated to predict the response of composite joints subjected to sagging moment, a situation which can occur in composite sway frames subjected to horizontal loads but not yet covered by the actual codes. Afterwards, the numerical tool used to predict the response of composite sway frames is validated through a benchmark study and through comparisons with experimental test results coming from two tests performed in European laboratories. With the so-validated software, the behaviour of actual sway building frames (i.e. frames extracted from existing buildings) is investigated, highlighting their particularities. The applicability to composite sway frames of two simplified analytical method initially developed for steel sway frames (an elastic one called the “amplified sway moment method” and a plastic one called the “Merchant-Rankine approach”) is then studied. From these investigations, it is demonstrated that the elastic method can be applied with good confidence to composite sway frames while the plastic one illustrates the same problems of accuracy already observed in previous studies on steel sway frames; in particular, the plastic method may prove to be very unsafe if the collapse mode associated to the ultimate limit state is a panel plastic mechanism. Finally, according to these results, a simplified analytical method is developed for the prediction of the ultimate load factor of steel and composite sway frames. The proposed method is founded on the Ayrton-Perry formulation and is validated through comparison to results obtained with full non-linear numerical analyses performed on more than 300 steel and composite frames. The so-validated method is easy to apply and permits to predict with a very good accuracy the ultimate load factor of a sway frame and the collapse mode appearing at the ultimate limit state. Founded on the knowledge gained from the previous topic on the structural behaviour of steel and composite structures, the behaviour of such structures subjected to an exceptional event is investigated within the second topic. The main objective is to propose a simplified analytical procedure to predict the development of the membrane forces within a structure further to the loss of a column and their effects on the structural response. In a first step, a general procedure allowing the prediction of the response of a structure further to the loss of a column is first defined, with a particular attention paid to the influence of the development of the catenary action on this response. Then, an experimental test performed at Liège University and simulating the loss of a column in a composite frame is described. The objective of this test is to observe the development of the catenary action within the tested structure and its effect on the joint behaviour. The described test constitutes a European first in this domain. Also, as for the previous topic, the behaviour of joints is investigated in details. Here, the particularity is the fact that the joints are subjected to combined bending moments and axial loads when the membrane effects developed in the structure. In a previous PhD thesis presented at Liège University, an analytical procedure founded on the component method was developed to predict the response of steel joints subjected to such loading. Within the present thesis, this method is extended to composite joints and validated through comparisons to experimental tests. Afterwards, the numerical tool used for the numerical investigations is validated through a benchmark study and through comparisons with the results of the experimental test performed at Liège University. In particular, the difficulty of simulating the actual behaviour of beam-to-column joints subjected to combined bending moments and axial loads is illustrated. With the so-validated software, a simplified substructure modelling, on which the developed analytical method is founded, is then validated. In addition, parametric numerical studies are performed on the substructure modelling in order to identify the parameters to be considered within the developed method. Finally, the developed simplified analytical method is described and validated through comparisons between the experimental results and the analytical prediction. With this “easy-to-apply” method, a very good accuracy is achieved; in particular, it is possible to predict the requested deformation capacity in the structural elements where plastic hinges are developed and the membrane forces which have to be supported by the structure [less ▲]

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See detailLa transmission du pouvoir dans les entreprises familiales
Pirnay, Fabrice ULg; LAMBRECHT, Johan

Report (2008)

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See detailOdour annoyance assessments around landfill sites:methods and results
Nicolas, Jacques ULg; Romain, Anne-Claude ULg; Delva, Julien ULg et al

in Chemical Engineering Transactions (2008, June), 15

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See detailFictions de l'universalité du savoir dans la Physiologie du goût de Brillat-Savarin
Stienon, Valérie ULg

in Signes, Discours et Sociétés. Revue semestrielle en sciences humaines et sociales dédiée à l'analyse des Discours (2008), 1

While nothing seemed to announce it, why did Brillat-Savarin become with his Physiologie du goût an important reference of French good taste in the field of gastronomy ? A study of discursive and ... [more ▼]

While nothing seemed to announce it, why did Brillat-Savarin become with his Physiologie du goût an important reference of French good taste in the field of gastronomy ? A study of discursive and enunciative processes used in this text can explain how the Physiologie has been conveniently fit into a discourse of French universalism, thanks to the development of a fictional complicity with the reader, and through the establishment of a pragmatic based on a special didactic relationship. These observations lead to the study of an ambiguous reference to science. [less ▲]

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See detailEffective arterial elastance as an index of pulmonary vascular load.
Morimont, Philippe ULg; Lambermont, Bernard ULg; Ghuysen, Alexandre ULg et al

in American Journal of Physiology - Heart and Circulatory Physiology (2008), 294(6), 2736-42

The aim of this study was to test whether the simple ratio of right ventricular (RV) end-systolic pressure (Pes) to stroke volume (SV), known as the effective arterial elastance (Ea), provides a valid ... [more ▼]

The aim of this study was to test whether the simple ratio of right ventricular (RV) end-systolic pressure (Pes) to stroke volume (SV), known as the effective arterial elastance (Ea), provides a valid assessment of pulmonary arterial load in case of pulmonary embolism- or endotoxin-induced pulmonary hypertension. Ventricular pressure-volume (PV) data (obtained with conductance catheters) and invasive pulmonary arterial pressure and flow waveforms were simultaneously recorded in two groups of six pure Pietran pigs, submitted either to pulmonary embolism (group A) or endotoxic shock (group B). Measurements were obtained at baseline and each 30 min after injection of autologous blood clots (0.3 g/kg) in the superior vena cava in group A and after endotoxin infusion in group B. Two methods of calculation of pulmonary arterial load were compared. On one hand, Ea provided by using three-element windkessel model (WK) of the pulmonary arterial system [Ea(WK)] was referred to as standard computation. On the other hand, similar to the systemic circulation, Ea was assessed as the ratio of RV Pes to SV [Ea(PV) = Pes/SV]. In both groups, although the correlation between Ea(PV) and Ea(WK) was excellent over a broad range of altered conditions, Ea(PV) systematically overestimated Ea(WK). This offset disappeared when left atrial pressure (Pla) was incorporated into Ea [Ea * (PV) = (Pes - Pla)/SV]. Thus Ea * (PV), defined as the ratio of RV Pes minus Pla to SV, provides a convenient, useful, and simple method to assess the pulmonary arterial load and its impact on the RV function. [less ▲]

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See detailHST observations of gravitationally lensed QSOs
Claeskens, Jean-François ULg; Sluse, Dominique ULg; Surdej, Jean ULg

in proceedings of the 41st ESLAB Symposium "The Impact of HST on European Astronomy" (June 2007) (2008, June)

Thanks to its sharp view, HST has significantly improved our knowledge of tens of gravitationally lensed quasars in four different respects: (1) confirming their lensed nature; (2) detecting the lensing ... [more ▼]

Thanks to its sharp view, HST has significantly improved our knowledge of tens of gravitationally lensed quasars in four different respects: (1) confirming their lensed nature; (2) detecting the lensing galaxy responsible for the image splitting; (3) improving the astrometric accuracy on the positions of the unresolved QSO images and of the lens; (4) resolving extended lensed structures from the QSO hosts into faint NIR or optical rings or arcs. These observations have helped to break some degeneracies on the lens potential, to probe the galaxy evolution and to reconstruct the true shape of the QSO host with an increased angular resolution. [less ▲]

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See detailOn the Role of the Deterministic and Circumferential Stresses in Throughflow Calculations
Simon, Jean-Francois; Léonard, Olivier ULg

in Proceedings of the ASME Turbo Expo 2008 (2008, June)

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See detailWhole body vibration and fibromyalgia: Influence on muscle performances
Maquet, Didier ULg; Philippe, Isabelle; Faymonville, Marie ULg et al

in Journal of Rehabilitation Medicine Supplement (2008, June), 47

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See detailAnalyse théorique et numérique de l'influence de la formulation des termes de production et de dissipation dans les équations d'écoulement à surface libre
Machiels, Olivier ULg

Master's dissertation (2008)

Depuis toujours, l’homme sait la richesse mais aussi le danger que représente l’eau. Il a donc sans cesse essayé de la maitriser. Dans ce souci de maitrise des écoulements, la modélisation de ceux-ci ... [more ▼]

Depuis toujours, l’homme sait la richesse mais aussi le danger que représente l’eau. Il a donc sans cesse essayé de la maitriser. Dans ce souci de maitrise des écoulements, la modélisation de ceux-ci représente un enjeu économique important. Les termes de frottement et de turbulence des différentes formulations à la base de l’hydraulique jouent un rôle capital pour l’efficacité de ces modélisations. C’est pourquoi de nombreux auteurs se sont intéressés à décrire le plus correctement ces termes de production et de dissipation. Dans la large gamme de formulations de frottement et de turbulence existante, il convient cependant de faire un tri. En effet, à chaque loi est associé un domaine de validité dépendant des hypothèses d’études qui ont mené à son élaboration. De plus, le succès qu’ont connu certaines lois est principalement dû à leur caractère simplifié qui pourrait cacher un manquement de rigueur physique. L’étude menée lors de ce travail a permis dans un premier temps de catégoriser les différentes lois afin de pouvoir comparer leurs domaines de validité et définir ainsi les lois à utiliser pour chaque modélisation (écoulement stationnaire ou non, régime laminaire ou turbulent, rugosité de fond plus ou moins importante,…). Cette étude comparative, portée sur les lois usuelles de frottement, est validée sur base de modélisations numériques. Celles-ci ont été menées sur des écoulements de rivière mettant en évidence les caractéristiques d’écoulement étudiées. Ce travail a donc permis d’établir les domaines de validité des différentes lois existantes sur base d’une représentation la plus proche possible de la physique réelle des écoulements. Il a également permit la mise en place d’une formulation continue capable de représenter numériquement l’ensemble des écoulements apparaissant sur une zone donnée (variation de hauteur d’eau, de débit, de rugosité,…). [less ▲]

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See detailInfluence de l’utilisation des combustibles de substitution sur le cycle de vie du ciment
Belboom, Sandra ULg

Master's dissertation (2008)

Dans ce travail de fin d’études, nous avons appliqué la méthodologie de l’Analyse de Cycle de Vie (ACV), également appelée méthodologie LCA (Life Cycle Assessment) à trois systèmes produisant du ciment et ... [more ▼]

Dans ce travail de fin d’études, nous avons appliqué la méthodologie de l’Analyse de Cycle de Vie (ACV), également appelée méthodologie LCA (Life Cycle Assessment) à trois systèmes produisant du ciment et utilisant chacun un taux différent d’utilisation des combustibles de substitution. Les trois systèmes envisagés sont :  Le système CBR Lixhe se basant sur les données techniques de 2006 de l’usine CBR Lixhe. Il utilise les combustibles de substitution pour plus de 50% des besoins en énergie du four de clinkérisation.  Le système BREF charbon qui est une modélisation d’une cimenterie se basant sur les émissions du document BREF Ciment et Chaux de 2001. Il utilise uniquement des combustibles fossiles, à savoir du gaz naturel et du charbon noir.  Le système SimaPro7.1 qui utilise la base de données Ciment de Portland du logiciel SimaPro7.1. L’évaluation des impacts environnementaux a été réalisée en utilisant la méthode normalisée (ISO 14042) Eco-Indicator 99. D’après les valeurs des scores globaux, quelle que soit la perspective envisagée, la charge environnementale du système CBR Lixhe sera moindre que celle du système SimaPro7.1 qui elle-même est moindre que celle du système BREF Charbon. En ce qui concerne les étapes des deux premiers systèmes envisagés (le système SimaPro7.1 n’est pas décomposable en étapes vu la globalité de la base de données), le four est l’étape prépondérante pour l’impact environnemental, ce qui était attendu. Dans le cadre de la perspective Hiérarchiste, définie dans la méthode Eco-Indicator 99 et employée dans ce travail, les dommages affectent tout d’abord la Santé humaine, puis les Ressources (extraction des combustibles fossiles) et enfin la Qualité de l’écosystème, et ce pour les trois systèmes envisagés. Dans le but de vérifier la validité du modèle, des systèmes et des hypothèses de travail, nous avons effectué une analyse de sensibilité. Les résultats obtenus lors de celle-ci montrent que, vu les données de départ, les systèmes sont correctement définis et que la méthodologie LCA – Eco-Indicator 99 est applicable au cycle envisagé. Ils mettent également en évidence les paramètres clés qui modifient de façon notable les scores globaux et qui pourront être régulés afin d’obtenir le meilleur score possible pour le cycle du ciment. [less ▲]

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See detailCombined Intra- and Inter-domain Traffic Engineering using Hot-Potato Aware Link Weights Optimization
Balon, Simon ULg; Leduc, Guy ULg

in ACM SIGMETRICS Performance Evaluation Review (2008), 36(1), 441-442

A well-known approach to intradomain traffic engineering consists in finding the set of link weights that minimizes a network-wide objective function for a given intradomain traffic matrix. This approach ... [more ▼]

A well-known approach to intradomain traffic engineering consists in finding the set of link weights that minimizes a network-wide objective function for a given intradomain traffic matrix. This approach is inadequate because it ignores a potential impact on interdomain routing due to hot-potato routing policies. This may result in changes in the intradomain traffic matrix that have not been anticipated by the link weights optimizer, possibly leading to degraded network performance. <br /> <br />We propose a BGP-aware link weights optimization method that takes these hot-potato effects into account. This method uses the interdomain traffic matrix and other available BGP data, to extend the intradomain topology with external virtual nodes and links, on which all the well-tuned heuristics of a classical link weights optimizer can be applied. Our method can also optimize the traffic on the interdomain peering links. [less ▲]

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See detailMichel Contat, Pour Sartre (Paris, Presses Universitaires de France, 2008)
Durand, Pascal ULg

in Année Sartrienne (L') : Bulletin du Groupe d'Etudes Sartriennes (2008), 22

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See detailPremiers résultats de l'enquête internationale sur les Pratiques Docimologiques dans l'Enseignement Supérieur (PraDES)
Gilles, Jean-Luc ULg

in Chafiqi, Fouad (Ed.) Mondialisation et éducation - Vers une société de la connaissance. Recueil des résumés des conférences et des communications (tome I) (2008, June)

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See detailRoom-acoustics predictions using a diffusion process – a state of the art
Billon, Alexis ULg

Conference (2008, June)

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See detailLe domaine universitaire du Sart Tilman Propositions d’aménagement de la zone Nord
Prégardien, Michel ULg; Collette, Jean-Pierre ULg

in Les Cahiers de l’Urbanisme (2008), 68

Il est désormais nécessaire de reconsidérer l’organisation du domaine universitaire du Sart Tilman, campus de l’Université de Liège, non seulement en se replaçant dans le contexte de l’époque actuelle ... [more ▼]

Il est désormais nécessaire de reconsidérer l’organisation du domaine universitaire du Sart Tilman, campus de l’Université de Liège, non seulement en se replaçant dans le contexte de l’époque actuelle, mais aussi dans l’optique d’une démarche prospective. Le présent article se concentre sur l’intervention dans la zone Nord, partie la plus peuplée du domaine, point d’entrée de l’université et donc limite stratégique entre la ville et son université. [less ▲]

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