Publications ORBi OA
Bookmark and Share    
Full Text
See detailL'astronomie dans le monde
Manfroid, Jean ULg

Article for general public (2007)

COROT; Etoiles proches; Energie noire aux débuts de l'univers; De nouvelles particules; Galaxie lointaine; Bombardement lunaire; Matière organique primitive dans des météorites; L'eau sur Mars; Extinction ... [more ▼]

COROT; Etoiles proches; Energie noire aux débuts de l'univers; De nouvelles particules; Galaxie lointaine; Bombardement lunaire; Matière organique primitive dans des météorites; L'eau sur Mars; Extinction K-T; Monts titaniens; Sous-sol martien; Stardust : les premiers résultats scientifiques; Obésité stellaire; Télescope géant [less ▲]

Detailed reference viewed: 12 (2 ULg)
Full Text
Peer Reviewed
See detailMicroeconomic co-evolution model for financial technical analysis signals
Rotundo, G.; Ausloos, Marcel ULg

in Physica A-Statistical Mechanics and its Applications (2007), 373

Technical analysis (TA) has been used for a long time before the availability of more sophisticated instruments for financial forecasting in order to suggest decisions on the basis of the occurrence of ... [more ▼]

Technical analysis (TA) has been used for a long time before the availability of more sophisticated instruments for financial forecasting in order to suggest decisions on the basis of the occurrence of data patterns. Many mathematical and statistical tools for quantitative analysis of financial markets have experienced a fast and wide growth and have the power for overcoming classical TA methods. This paper aims to give a measure of the reliability of some information used in TA by exploring the probability of their occurrence within a particular microeconomic agent-based model of markets, i.e., the co-evolution Bak-Sneppen model originally invented for describing species population evolutions. After having proved the practical interest of such a model in describing financial index so-called avalanches, in the prebursting bubble time rise, the attention focuses on the occurrence of trend line detection crossing of meaningful barriers, those that give rise to some usual TA strategies. The case of the NASDAQ crash of April 2000 serves as an illustration. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 5 (1 ULg)
Full Text
Peer Reviewed
See detailDiscovery of magnetic fields in three He variable Bp stars with He and Si spots
Briquet, Maryline ULg; Hubrig, S.; Schöller, M. et al

in Astronomische Nachrichten (2007), 328

It is essential for the understanding of stellar structure models of high mass stars to explain why constant stars, non-pulsating chemically peculiar hot Bp stars and pulsating stars co-exist in the ... [more ▼]

It is essential for the understanding of stellar structure models of high mass stars to explain why constant stars, non-pulsating chemically peculiar hot Bp stars and pulsating stars co-exist in the slowly pulsating B stars and β Cephei instability strips. We have conducted a search for magnetic fields in the four Bp stars HD 55522, HD 105382, HD 131120, and HD 138769 which previously have been wrongly identified as slowly pulsating B stars. A recent study of these stars using the Doppler Imaging technique revealed that the elements He and Si are inhomogeneously distributed on the stellar surface, causing the periodic variability. Using FORS 1 in spectropolarimetric mode at the VLT, we have acquired circular polarisation spectra to test the presence of a magnetic field in these stars. A variable magnetic field is clearly detected in HD 55522 and HD 105382, but no evidence for the existence of a magnetic field was found in HD 131120. The presence of a magnetic field in HD 138769 is suggested by one measurement at 3 σ level. We discuss the occurrence of magnetic B stars among the confirmed pulsating B stars and find strong magnetic fields of order kG and oscillations to be mutually exclusive. Based on observations collected at the European Southern Observatory, Paranal, Chile (ESO programmes 71.D-0308(A), 072.D-0377(A), and 073.D-0466(A)). [less ▲]

Detailed reference viewed: 7 (0 ULg)
Full Text
Peer Reviewed
See detailA deconvolution-based algorithm for crowded field photometry with unknown point spread function
Magain, Pierre ULg; Courbin, F.; Gillon, Michaël ULg et al

in Astronomy and Astrophysics (2007), 461

A new method is presented for determining the point spread function (PSF) of images that lack bright and isolated stars. It is based on the same principles as the MCS image deconvolution algorithm. It ... [more ▼]

A new method is presented for determining the point spread function (PSF) of images that lack bright and isolated stars. It is based on the same principles as the MCS image deconvolution algorithm. It uses the information contained in all stellar images to achieve the double task of reconstructing the PSFs for single or multiple exposures of the same field and to extract the photometry of all point sources in the field of view. The use of the full information available allows us to construct an accurate PSF. The possibility to simultaneously consider several exposures makes it well suited to the measurement of the light curves of blended point sources from data that would be very difficult or even impossible to analyse with traditional PSF fitting techniques. The potential of the method for the analysis of ground-based and space-based data is tested on artificial images and illustrated by several examples, including HST/NICMOS images of a lensed quasar and VLT/ISAAC images of a faint blended Mira star in the halo of the giant elliptical galaxy NGC 5128 (Cen A). [less ▲]

Detailed reference viewed: 26 (4 ULg)
Full Text
Peer Reviewed
See detailL'art de la fugue
Paques, Frédéric ULg

in 9e Art : Les Cahiers du Musée de la Bande Dessinée (2007), 13

Detailed reference viewed: 22 (3 ULg)
Full Text
See detailPALETTE : User centred description of PALETTE tools and services and first analysis of usability
Vandeput, Etienne ULg; Denis, Brigitte ULg; Ledent, M. et al

Report (2007)

The present deliverable aims at providing any CoP member, CoP animator or CoP mediator with the most complete view of the PALETTE tools and services. It gives a voice to the developer, the educationalist ... [more ▼]

The present deliverable aims at providing any CoP member, CoP animator or CoP mediator with the most complete view of the PALETTE tools and services. It gives a voice to the developer, the educationalist, the ergonomist and of course the user to explain how they consider them. So, it suggests use cases, scenarios but also shows to the reader where are the obstacles of use (with the aim of avoiding a too quick discouragement on his/her part) and it provides real users’ testimonies. It illustrates the participative design, core of the project, by showing how various kinds of partners in the project work at their evolvement. Several times, it evokes how they interact in that way. More, for the sake of completeness, external services which are "social network" oriented, are described in terms of functionalities and with the concern of providing the audience with a largest view of how ICT may help CoPs to grow up. [less ▲]

Detailed reference viewed: 15 (1 ULg)
Full Text
See detailAbstract numeration systems and recognizability
Charlier, Emilie ULg

Conference (2007, January)

In this talk, I will present some results concerning multiplication by a constant in an abstract numeration system built on a bounded language. More precisely, we will show that this operation does not ... [more ▼]

In this talk, I will present some results concerning multiplication by a constant in an abstract numeration system built on a bounded language. More precisely, we will show that this operation does not preserve regularity, and therefore cannot be computed by a finite automaton. [less ▲]

Detailed reference viewed: 10 (1 ULg)
Full Text
See detailVers une gestion intégrée et participative de la forêt? L'exemple de la commune de Nassogne
Lejeune, Philippe ULg; Claessens, Hugues ULg; Alderweireld, Matthieu ULg et al

in Forêt Wallonne (2007), (86), 11-23

Un projet pilote de gestion intégrée et participative d’un massif forestier est en cours depuis 1998 sur une étendue de 20 000 hectares au plateau de Saint-Hubert. En quoi consiste une telle démarche ... [more ▼]

Un projet pilote de gestion intégrée et participative d’un massif forestier est en cours depuis 1998 sur une étendue de 20 000 hectares au plateau de Saint-Hubert. En quoi consiste une telle démarche ? Quel est son intérêt ? Comment se différencie-t-elle d’un aménagement classique ? Voici, entre autres, les questions auxquelles cet article tente de répondre à partir de l’exemple de la révision de l’aménagement de la propriété forestière communale de Nassogne. [less ▲]

Detailed reference viewed: 69 (18 ULg)
Full Text
Peer Reviewed
See detailA prospective randomised multicentre study comparing continuous and intermittent treatment with celecoxib in patients with osteoarthritis of the knee or hip
Luyten, F. P.; Geusens, P.; Malaise, Michel ULg et al

in Annals of the Rheumatic Diseases (2007), 66(1), 99-106

Objective: To compare the effects of continuous and intermittent celecoxib treatment in patients with knee or hip osteoarthritis in flare. Methods: In this 24-week, prospective, randomised, double-blind ... [more ▼]

Objective: To compare the effects of continuous and intermittent celecoxib treatment in patients with knee or hip osteoarthritis in flare. Methods: In this 24-week, prospective, randomised, double-blind, placebo-controlled study, patients were randomly assigned to receive continuous (n = 62) or intermittent (n = 61) treatment with celecoxib 200 mg once daily. The primary efficacy end point was the area under the curve (AUC) of the change in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total scores between baseline and week 24 divided by the time interval. Secondary end points included the percentage of days with intake of the flare drug, the AUC of the change in the WOMAC total scores, the mean change from baseline in the WOMAC scores, and the patient's and physician's global assessment of osteoarthritis. Results: There were no significant differences between patients randomised to continuous or intermittent treatment in the primary end point or most of the secondary end points, although a consistent trend supporting continuous treatment was observed. The percentage of days with intake of the flare drug was significantly lower (p = 0.031) in the group receiving continuous versus intermittent celecoxib. Both treatment regimens were well tolerated. Conclusion: The results of this pilot study indicate a potential clinical difference between continuous and intermittent treatment with celecoxib, and may be useful in designing future trials. A larger trial on both efficacy and safety outcomes is required for conclusive evidence in favour of either continuous or intermittent treatment. [less ▲]

Detailed reference viewed: 26 (3 ULg)
Full Text
Peer Reviewed
See detailLe traitement de la pericardite recidivante: a propos d'un cas et revue de la litterature
Martin y Porras, M.; Waleffe, André ULg; Pierard, Luc ULg

in Revue Médicale de Liège (2007), 62(1), 21-4

Benign acute pericarditis is a common disorder. Recurrence is probably the most troublesome complication, characterized by a return of pericardial pain after recovery from an episode of typical acute ... [more ▼]

Benign acute pericarditis is a common disorder. Recurrence is probably the most troublesome complication, characterized by a return of pericardial pain after recovery from an episode of typical acute pericarditis. Treatment of recurrence is often difficult and the guidelines issued by scientific societies remain vague. A number of investigators published enthusiastic reports on the efficacy of colchicine as adjuvant treatment of recurrent pericarditis and other authors suggested that colchicine should also be used as part of the treatment regimen of acute pericarditis. Colchicine is effective and safe and may be proposed as treatment of choice, especially in the idiopathic form. Treatment with corticosteroids exacerbates and extends the course of recurrent pericarditis and attenuates the efficacy of colchicine. [less ▲]

Detailed reference viewed: 39 (0 ULg)
Full Text
Peer Reviewed
See detailSolutions imaginées par les enseignants en éducation physique du secondaire pour lutter contre le phénomène de la dispense dans le cours de natation
Motter, Pascale; Maraite, Anne-Aymone ULg; Cloes, Marc ULg

in e Journal de la Recherche sur l'Intervention en Éducation Physique et Sport (2007), 11

En Communauté française de Belgique, les professeurs d’éducation physique de l’enseignement secondaire sont actuellement confrontés à une augmentation du nombre d’élèves cherchant à ne pas participer à ... [more ▼]

En Communauté française de Belgique, les professeurs d’éducation physique de l’enseignement secondaire sont actuellement confrontés à une augmentation du nombre d’élèves cherchant à ne pas participer à leurs cours. Ce phénomène atteint des proportions particulièrement préoccupantes dans les cours de natation, avec les classes de filles. Cette étude s’intéresse aux pistes d’actions expérimentées par 50 enseignantes qui ont été interviewées par téléphone. Les réponses ont été classées inductivement dans un système de catégories avec un taux de 97,2% d’accords intra-analystes. Trois types de solutions ont été identifiées : (1) celles qui ont donné des résultats positifs ; (2) celles qui se sont montrées inefficaces et (3) celles que les sujets souhaiteraient tester. Parmi les premières (n = 46), les actions les plus fréquentes se répartissent entre une catégorie coercitive (« menaces/sanctions ») et une catégorie constructive (« Contenu des séances »). Plusieurs autres pistes originales sont discutées. Les solutions s’étant montrées inefficaces s’avèrent étonnamment similaires aux précédentes, mettant en exergue l’extrême variabilité des effets des stimuli pédagogiques. Enfin, il est encourageant de constater que certains enseignants se mobilisent afin de résoudre les problèmes rencontrés sur le terrain. Deux exemples de solutions à expérimenter ont ainsi été identifiés et discutés. [less ▲]

Detailed reference viewed: 208 (16 ULg)
Full Text
Peer Reviewed
See detailPreconditioning of the tumor vasculature and tumor cells by intermittent hypoxia: implications for anti-cancer therapies
Martinive, Philippe ULg

Poster (2007, January)

Hypoxia is a common feature in tumors associated with an increased resistance of tumor cells to therapies. In addition to O(2) diffusion-limited hypoxia, another form of tumor hypoxia characterized by ... [more ▼]

Hypoxia is a common feature in tumors associated with an increased resistance of tumor cells to therapies. In addition to O(2) diffusion-limited hypoxia, another form of tumor hypoxia characterized by fluctuating changes in pO(2) within the disorganized tumor vascular network is described. Here, we postulated that this form of intermittent hypoxia promotes endothelial cell survival, thereby extending the concept of hypoxia-driven resistance to the tumor vasculature. We found that endothelial cell exposure to cycles of hypoxia reoxygenation not only rendered them resistant to proapoptotic stresses, including serum deprivation and radiotherapy, but also increased their capacity to migrate and organize in tubes. By contrast, prolonged hypoxia failed to exert protective effects and even seemed deleterious when combined with radiotherapy. The use of hypoxia-inducible factor-1alpha (HIF-1alpha)-targeting small interfering RNA led us to document that the accumulation of HIF-1alpha during intermittent hypoxia accounted for the higher resistance of endothelial cells. We also used an in vivo approach to enforce intermittent hypoxia in tumor-bearing mice and found that it was associated with less radiation-induced apoptosis within both the vascular and the tumor cell compartments (versus normoxia or prolonged hypoxia). Radioresistance was further ascertained by an increased rate of tumor regrowth in irradiated mice preexposed to intermittent hypoxia and confirmed in vitro using distinctly radiosensitive tumor cell lines. In conclusion, we have documented that intermittent hypoxia may condition endothelial cells and tumor cells in such a way that they are more resistant to apoptosis and more prone to participate in tumor progression. Our observations also underscore the potential of drugs targeting HIF-1alpha to resensitize the tumor vasculature to anticancer treatments. PMID: 17178869 [PubMed - indexed for MEDLINE] [less ▲]

Detailed reference viewed: 46 (14 ULg)
Full Text
Peer Reviewed
See detailThird Belgian multicentre survey of antibiotic susceptibility of anaerobic bacteria
Wybo, Ingrid; Piérard, Denis ULg; Verschraegen, Inge et al

in Journal of Antimicrobial Chemotherapy (2007), 59(1), 132-139

Objectives: To collect recent data on the susceptibility of anaerobes and to compare them with results from previous studies. Methods: Four hundred and forty-three anaerobic clinical isolates from various ... [more ▼]

Objectives: To collect recent data on the susceptibility of anaerobes and to compare them with results from previous studies. Methods: Four hundred and forty-three anaerobic clinical isolates from various body sites were prospectively collected from October 2003 to February 2005 in nine Belgian hospitals. MICs were determined for nine anti-anaerobic and three recently developed antibiotics. Results: Most Gram-negative bacilli except Fusobacterium spp. were resistant to penicillin. Piperacillin/tazobactam, metronidazole, chloramphenicol, meropenem and amoxicillin/clavulanic acid were very active against all groups, but only 86% of Bacteroides fragilis group strains were susceptible to the latter. Cefoxitin, cefotetan and clindamycin were less active. In particular, only 62%, 52% and 48% of B. fragilis group strains were susceptible, respectively. Clindamycin shows a continuing decrease in activity, as 83% were still susceptible in 1987 and 66% in 1993-94. Anti-anaerobic activity of the new antibiotics is interesting, with MIC50 and MIC90 of 1 and > 32 mg/L for moxifloxacin, 2 and 4 mg/L for linezolid and 0.5 and 8 mg/L for tigecycline. Conclusions: The susceptibility of anaerobic bacteria remains stable in Belgium, except for clindamycin, which shows a continuous decrease in activity. However, for each of the tested antibiotics, at least a few resistant organisms were detected. Consequently, for severe infections involving anaerobic bacteria, it could be advisable to perform microbiological testing instead of relying on known susceptibility profiles. Periodically monitoring background susceptibility remains necessary to guide empirical therapy. [less ▲]

Detailed reference viewed: 23 (4 ULg)
Full Text
See detailUne déontologie manipulée ?
Durand, Pascal ULg; Grégoire, Arnaud

Article for general public (2007)

Detailed reference viewed: 49 (5 ULg)
Full Text
Peer Reviewed
See detailMiroir interne déformant de l'image de soi : élaboration conceptuelle intégrant la clinique et les découvertes récentes des neurosciences
Scholl, Jean-Marc ULg; Philippe, Paule ULg

Poster (2007, January)

Neurosciences : Un réseau neuronal spécifiquement référé au "self" du sujet est mis en évidence en neuroimagerie (Ph Fossati). Il intervient pour se remémore des attributs référés au self. Ce réseau est ... [more ▼]

Neurosciences : Un réseau neuronal spécifiquement référé au "self" du sujet est mis en évidence en neuroimagerie (Ph Fossati). Il intervient pour se remémore des attributs référés au self. Ce réseau est différent de celui qui permet au sujet de donner des attributs à d'autres individus. Le réseau référé au self permet d'être en contact immédiat avec l'image et la connaissance de soi. De plus, le rappel mnésique des attributs positifs et négatifs référés au self met en jeu des réseaux neuronaux différents. Les attributs positifs référés au self activent la région préfrontale antéromédiane droite, les attributs négatifs référés au self la région préfrontale dorsolatérale droite. Le sujet sain active les deux réseaux de façon simultanée pour restituer une image de soi intégrée. Définition conceptuelle: Le "miroir interne" – distingué de l'objet qui lui est présenté – correspond¬ au réseau neuronal référé spécifiquement au self. Ce réseau accède à l'image de soi. S'il y a un dysfonctionnement du réseau référé au self, il restitue une image déformée de soi, et le "miroir interne" devient déformant. Le sujet associera son identité à cette image déformée. Clinique du «miroir interne déformant de l'image de soi» : Le regard de l'enfant sur lui-même lui renvoie une image plus négative que ce que ses interlocuteurs ne perçoivent de lui. Dès le départ, l'enfant a une mauvaise perception de lui-même. Lorsqu'un interlocuteur lui fait une remarque, l'enfant bascule dans une image déformée et bien plus négative que celle que ne lui prête l'interlocuteur. Un dysfonctionnement de ces réseaux déséquilibre la balance et ne fait apparaître "qu'une seule couleur" dans le "miroir interne" par une restitution mnésique univoque : ou des attributs positifs, ou des attributs négatifs. Une prépondérance de l'image négative évoque un terrain dépressif, des personnalités évitante ou dépendante. Une prépondérance de l'image positive évoque des personnalités narcissiques, une image mégalomaniaque. Un dysfonctionnement neuronal peut induire une labilité et une instabilité de cette image (borderline), ou, une bascule rapide en "on-off" d'images positives et négatives de soi (rencontrée en pédopsychiatrie). Une psychoéducation permet la prise de conscience de ce miroir interne déformant. [less ▲]

Detailed reference viewed: 71 (2 ULg)
Full Text
See detailCutting planes from lattice-point-free polyhedra
Louveaux, Quentin ULg

Conference (2007, January)

In this talk, we generalize the concept of a split (that leads to split cuts) to any lattice-point-free polyhedron. We show how we can generate cutting planes for a polyhedron from these objects ... [more ▼]

In this talk, we generalize the concept of a split (that leads to split cuts) to any lattice-point-free polyhedron. We show how we can generate cutting planes for a polyhedron from these objects. Associated to any lattice-point-free polyhedron, we define a "split-dimension" (which is equal to 1 in the case of a split in the usual sense). We then consider the operation of adding to a polyhedron all cutting planes that we can obtain from considering all the lattice-point-free polyhedra with a split-dimension lower or equal to d. We call the obtained object the "d-dimensional split closure" of the initial polyhedron. We discuss whether this object is again a polyhedron or not. As an important illustration, we focus on objects of split-dimension equal to 1 or 2. [less ▲]

Detailed reference viewed: 14 (0 ULg)
Full Text
Peer Reviewed
See detailA novel 24-base pair deletion in the coding region of CCR5 in an African population
Karasi, Jean Claude ULg

in AIDS (2007), 21(1), 111-113

Detailed reference viewed: 17 (1 ULg)
Full Text
Peer Reviewed
See detailLe depistage du cancer colorectal
Piront, Patricia ULg; Louis, Edouard ULg; Belaiche, Jacques ULg et al

in Revue Médicale de Liège (2007), 62(1), 15-20

Colorectal cancer is the second leading cause of death in Northern countries and need a national screening program to reduce mortality and improve quality of life. Screening has to be cost-effective and ... [more ▼]

Colorectal cancer is the second leading cause of death in Northern countries and need a national screening program to reduce mortality and improve quality of life. Screening has to be cost-effective and acceptable for patients. Many screening tools, invasive or not, are existing and often debated: FOBT, sigmoidoscopy and complete colonoscopy. New tools are in development and have to be evaluated in current practice: virtual colonoscopy, new endoscopic technologies, DNA on faeces or proteomics with markers in serum. [less ▲]

Detailed reference viewed: 195 (2 ULg)