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See detailCharacterisation of disks around YSOs with GENIE
Kaltenegger, Lisa; Absil, Olivier ULg; Eiroa, Carlos et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

Recent interferometric observations show that the interfered near-IR size of the circumstellar material around Young Stellar Object (YSO) are larger than those expected from accretion disk models. There ... [more ▼]

Recent interferometric observations show that the interfered near-IR size of the circumstellar material around Young Stellar Object (YSO) are larger than those expected from accretion disk models. There are currently different models that account for the excess IR emission of Young Stellar Objects (YSO). At the same time, the answers to many questions on the evolutionary status and the origin of the activity and variability depend critically on the relative importance of circumstellar distribution of material in disks or envelopes at different spatial scales. Operating at mid-infrared wavelengths, the Ground-based European Nulling Interferometer Experiment (GENIE) will be particularly sensitive to warm circumstellar dust and will thus provide the opportunity to characterize dust disks around YSOs. Observations with GENIE will enable us to investigate the properties of the circumstellar dust, which are responsible for the excess near-infrared fluxes. The nulling of the central star will bring out the disk in much more detail and hence put stronger constraints on these models. [less ▲]

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See detailCan GENIE characterize debris disks around nearby stars?
Absil, Olivier ULg; Kaltenegger, L.; Eiroa, C. et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

The Ground-based European Nulling Interferometer Experiment will combine the light collected by two or more VLT telescopes and make them interfere in a destructive way, thereby revealing the close ... [more ▼]

The Ground-based European Nulling Interferometer Experiment will combine the light collected by two or more VLT telescopes and make them interfere in a destructive way, thereby revealing the close neighborhood of nearby stars. Operating at mid-infrared wavelengths, GENIE will be particularly sensible to warm circumstellar dust. This paper presents simulated observations of the debris disk around the nearby A2V star zeta Leporis obtained with the GENIE simulation software. Parameters such as inclination, density power-law exponent and inner radius can be retrieved with a relative precision of 1% or better using only six observations of 15 minutes. In the context of the DARWIN/TPF mission, warm circumstellar dust could be a serious limitation to the detection of Earth-like exoplanets. This paper shows that GENIE will detect disks as faint as 23 times our local zodiacal cloud around Sun-like stars at 10 pc, and will thus allow to discard unsuitable targets for DARWIN/TPF. [less ▲]

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See detailGENIEsim: the GENIE simulation software
Absil, Olivier ULg; den Hartog, R.; Erd, C. et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

GENIEsim, the GENIE simulation software, is an IDL-based code to simulate future observations with the Ground-based European Nulling Interferometer Experiment, which should be commissioned on the Very ... [more ▼]

GENIEsim, the GENIE simulation software, is an IDL-based code to simulate future observations with the Ground-based European Nulling Interferometer Experiment, which should be commissioned on the Very Large Telescope Interferometer (VLTI) in 2007. The code simulates operation in the mid-infrared (L' and N bands) and includes all major noise sources. The atmospheric turbulence is described by a Kolmogorov power spectrum, from which random time series are computed for perturbations to the optical paths. The effect of turbulence is reduced by means of control loops, which are either included in the VLTI facility (MACAO, PRIMA) or specific to the GENIE instrument. The output of GENIEsim is a time series of fluxes computed by integration of a source field multiplied by the GENIE transmission map, projected onto the plane of the sky. Simulations have already allowed to identify critical points in the design of the instrument, such as OPD and dispersion control, calibration of stellar leakage and background subtraction. [less ▲]

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See detailThe Ground-based European Nulling Interferometry Experiment (DARWIN-GENIE)
Gondoin, P.; Absil, Olivier ULg; den Hartog, R. et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

Darwin is one of the most challenging space projects ever considered by the European Space Agency (ESA). Its principal objectives are to detect Earth-like planets around nearby stars and to characterise ... [more ▼]

Darwin is one of the most challenging space projects ever considered by the European Space Agency (ESA). Its principal objectives are to detect Earth-like planets around nearby stars and to characterise their atmospheres. Darwin is conceived as a space "nulling interferometer" which makes use of on-axis destructive interferences to extinguish the stellar light while keeping the off-axis signal of the orbiting planet. Within the frame of the Darwin program, the European Space Agency (ESA) and the European Southern Observatory (ESO) intend to build a ground-based technology demonstrator called GENIE (Ground based European Nulling Interferometry Experiment). Such a ground-based demonstrator built around the Very Large Telescope Interferometer (VLTI) in Paranal will test some of the key technologies required for the Darwin Infrared Space Interferometer. It will demonstrate that nulling interferometry can be achieved in a broad mid-IR band as a precursor to the next phase of the Darwin program. [less ▲]

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See detailCould GENIE detect hot Jupiters?
den Hartog, Roland; Absil, Olivier ULg; Kaltenegger, L. et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

The prime objective of GENIE (Ground-based European Nulling Interferometry Experiment) is to obtain experience with the design, construction and operation of an IR nulling interferometer, as a preparation ... [more ▼]

The prime objective of GENIE (Ground-based European Nulling Interferometry Experiment) is to obtain experience with the design, construction and operation of an IR nulling interferometer, as a preparation for the DARWIN/TPF mission. In this context, the detection of a planet orbiting another star would provide an excellent demonstration of nulling interferometry. Doing this through the atmosphere, however, is a formidable task. In this paper we assess the prospects of detecting, with nulling interferometry on ESO's VLT, a Hot Jupiter, a giant planet in a close orbit around its parent star. First we discuss the definition of the optimal target. Then we present a simulated observation of the Tau Bootis system, which suggests that GENIE, in a L'-band single Bracewell configuration, could detect the hot Jupiter in a few hours time with a signal-to-noise ratio of up to ~80. Although there are strong requirements on the control-loop performance, background subtraction and accuracy of the photometry calibration, we conclude that at present there do not seem to be fundamental problems that would prevent GENIE from detecting hot Jupiters. Hence the answer to the question in the title is yes. [less ▲]

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See detailOverview of the DARWIN mission
Kaltenegger, L.; Karlsson, A.; Fridlund, M. et al

in Fridlund, Malcolm; Henning, Thomas (Eds.) Towards Other Earths: DARWIN/TPF and the Search for Extrasolar Terrestrial Planets (2003, October 01)

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See detailThe timing of normal puberty and the age limits of sexual precocity: Variations around the world, secular trends, and changes after migration
Parent, Anne-Simone ULg; Teilmann, G.; Juul, A. et al

in Endocrine Reviews (2003), 24(5), 668-693

During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been ... [more ▼]

During the past decade, possible advancement in timing of puberty has been reported in the United States. In addition, early pubertal development and an increased incidence of sexual precocity have been noticed in children, primarily girls, migrating for foreign adoption in several Western European countries. These observations are raising the issues of current differences and secular trends in timing of puberty in relation to ethnic, geographical, and socioeconomic background. None of these factors provide an unequivocal explanation for the earlier onset of puberty seen in the United States. In the formerly deprived migrating children, refeeding and catch-up growth may prime maturation. However, precocious puberty is seen also in some nondeprived migrating children. Attention has been paid to the changing milieu after migration, and recently, the possible role of endocrine-disrupting chemicals from the environment has been considered. These observations urge further study of the onset of puberty as a possible sensitive and early marker of the interactions between environmental conditions and genetic susceptibility that can influence physiological and pathological processes. [less ▲]

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See detailStudy of antirestenosis with the BiodivYsio dexamethasone-eluting stent (STRIDE): A first-in-human multicenter pilot trial
Liu, X. S.; Huang, Y. M.; Hanet, C. et al

in Catheterization and Cardiovascular Interventions : Official Journal of the Society for Cardiac Angiography & Interventions (2003), 60(2), 172-178

The aim of this multicenter pilot study was to evaluate the acute safety and efficacy of the dexamethasone-eluting stent (0.5 mug/mm(2) of stent) implanted in patients with de novo single-vessel disease ... [more ▼]

The aim of this multicenter pilot study was to evaluate the acute safety and efficacy of the dexamethasone-eluting stent (0.5 mug/mm(2) of stent) implanted in patients with de novo single-vessel disease. This study included 71 patients, 42% of whom had unstable angina pectoris. An appropriately sized BiodivYsio Matrix Lo stent loaded with a total dexamethasone dose of 0.5 mug/mm(2) of stent was used. Technical device success rate was 95%. Six-month MACE occurred in two patients (3.3%). Binary restenosis rate was 13.3%. Late loss was 0.45. Late loss and percent diameter stenosis were lower in the unstable angina pectoris patients compared to the stable patients (0.32 +/- 0.39 vs. 0.60 +/- 0.55 mm, P < 0.07, and 26.86 +/- 14 vs. 38.40 +/- 16%, P < 0.02). This study demonstrated the feasibility and safety of the implantation of a dexamethasone-eluting stent and its effect on in-stent neointimal hyperplasia. (C) 2003 Wiley-Liss, Inc. [less ▲]

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See detailLe dosage rapide des peptides natriuretiques cardiaques. Une nouvelle contribution au diagnostic, au suivi therapeutique et au pronostic des affections cardio-vasculaires
Borgoens, Philippe ULg; Pierard, Luc ULg

in Revue Médicale de Liège (2003), 58(10), 615-20

Only about half of the diagnoses of heart failure are correct. The limitations of clinical judgment and complementary investigations are described in this article. Recently, BNP was found to be a good ... [more ▼]

Only about half of the diagnoses of heart failure are correct. The limitations of clinical judgment and complementary investigations are described in this article. Recently, BNP was found to be a good biological marker of ventricular dysfunction. Rapid and reliable BNP measurement is now available and the clinical value of this peptide was examined in many studies. The role of BNP in the diagnosis and management of heart failure will be increasing. [less ▲]

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See detailLe cas clinique du mois. Precordialgies evoquant un syndrome coronaire instable, un ecueil diagnostique
Gach, Olivier ULg; Troisfontaines, Paul ULg; Legrand, Victor ULg

in Revue Médicale de Liège (2003), 58(10), 611-4

Chest pain represents a frequent motivation for consultation in which the differential diagnosis is not always easy. We present a case where a misdiagnosis lead to serious complications. Therefore we ... [more ▼]

Chest pain represents a frequent motivation for consultation in which the differential diagnosis is not always easy. We present a case where a misdiagnosis lead to serious complications. Therefore we review the clinical and electrocardiographic characteristics of the evoked diagnosis. [less ▲]

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See detailExposition hormonale precoce et repercussions comportementales dans l'hyperplasie congenitale des surrenales: a propos d'un cas
Tortolani, Isabelle ULg; Scantamburlo, Gabrielle ULg; Ansseau, Marc ULg et al

in Revue Médicale de Liège (2003), 58(10), 631-4

Congenital adrenal hyperplasia is a recessive autosomal transmission endocrine pathology that exposes people who suffer from it to an abnormally high concentration of adrenal androgens during the prenatal ... [more ▼]

Congenital adrenal hyperplasia is a recessive autosomal transmission endocrine pathology that exposes people who suffer from it to an abnormally high concentration of adrenal androgens during the prenatal and early postnatal periods. This disease induces female's virilism of variable degree. The case of a 29 year-old patient, who suffers from this affection and also presents a psychiatric disorder, raises questions about the possible consequences of an early exposure to androgens on the adult behaviour. [less ▲]

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See detailCharacteristics of adolescent attempts to manage overweight
Grignard, Sophie ULg; Bourguignon, Jean-Pierre ULg; Born, Michel ULg et al

in Patient Education & Counseling (2003), 51(2), 183-189

This study evaluates the actions taken by obese adolescents in an attempt to lose weight in relation to changes in weight. Particular emphasis is put on the context surrounding the management process ... [more ▼]

This study evaluates the actions taken by obese adolescents in an attempt to lose weight in relation to changes in weight. Particular emphasis is put on the context surrounding the management process. Thirty one obese adolescents aged 14-18 participated in this study. The adolescents answered a written questionnaire, took a body-size dissatisfaction test and were interviewed. Their family physicians were interviewed by telephone. Quantitative data concerned changes in weight and body-size dissatisfaction scores. Qualitative analysis included cases analyses and building up of synthesis variables. Loss of weight is linked with continuity of management attempts as well as with medical follow-up. The most frequent management attempt is diet. Self-image is correlated with weight. The exclusive emphasis put on diet is discussed in relation to the importance of more psychosocial factors such as self-image, denial and attraction to discontinuity. Some recommendations for the management of overweight adolescents are then outlined. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved. [less ▲]

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See detailAn investigation of verbal short-term memory and phonological processing in four children with Williams syndrome
Majerus, Steve ULg; Barisnikov, K.; Vuillemin, I. et al

in Neurocase : Case Studies in Neuropsychology, Neuropsychiatry & Behavioural Neurology (2003), 9(5), 390-401

Although phonological processing is generally considered to be a proficiency in Williams syndrome (WS), there are very few studies which have extensively explored phonological processing abilities in WS ... [more ▼]

Although phonological processing is generally considered to be a proficiency in Williams syndrome (WS), there are very few studies which have extensively explored phonological processing abilities in WS. In this study, we re-assessed phonological processing in WS by exploring verbal STM and phonological awareness abilities in 4 children with WS (CA: 10-12 years) and two control groups, one matched for chronological age (CA) and the other matched for verbal mental age (VA). Our results confirm and extend previous claims of preserved phonological STM in WS by showing specifically preserved STM performance for non-words, compared to both VA and CA control groups. However, we observed that this was the case only for non-words where support of phonological and lexico-semantic knowledge was minimized, with reduced phonological and lexico-semantic effects on STM performance. Furthermore, a more direct assessment of phonological processing abilities through phonological awareness tasks showed impaired performance for the 4 WS children. Our data confirm that STM for non-words represents a real strength in. WS but they do not support previous assumptions of a more general preservation of phonological processing abilities in WS. Implications for impaired and preserved cognitive processes underlying verbal STM and phonological awareness abilities in WS are discussed. [less ▲]

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See detailTraitement de la lombalgie chronique : intérêts du reconditionnement physique
Vanderthommen, Marc ULg; Demoulin, Christophe ULg; charlier, M. et al

in Abstract book du Symposium FNDLK – Kinésithérapie passive ou active ? (2003, October)

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See detailProfil isocinétique des fléchisseurs et extenseurs du coude
Maquet, Didier ULg; Croisier, Jean-Louis ULg; Forthomme, Bénédicte ULg et al

in Abstract book des 4èmes Journées Belges d’Isocinétisme (2003, October)

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See detailEvaluation d'une méthode de prédiction des déplacements de terminaux dans les réseaux mobiles
François, Jean-Marc; Leduc, Guy ULg; Martin, Sylvain ULg

in Ingénierie des protocoles - Réseaux mobiles et ad hoc, qualité de service, test et validation (2003, October)

Dans les réseaux mobiles, la prédiction du déplacement des terminaux fait régulièrement l'objet d'études: c'est une étape importante sur le chemin des garanties de QoS dans ces réseaux. Dans les ... [more ▼]

Dans les réseaux mobiles, la prédiction du déplacement des terminaux fait régulièrement l'objet d'études: c'est une étape importante sur le chemin des garanties de QoS dans ces réseaux. Dans les infrastructures actuelles, les sources d'informations permettant d'induire le déplacement d'un mobile sont multiples; de plus, le cas des terminaux incapables d'émettre de telles informations est aussi fréquent qu'important. Dans ces conditions, pour qu'un mécanisme de prédiction puisse se déployer, il lui faut pouvoir s'adapter à cette diversité de façon flexible. L'évaluation d'un tel mécanisme est le sujet de cet article; il s'agit d'une méthode simple et s'appuyant sur peu d'hypothèses. [less ▲]

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See detailReconnaissance des cultes : le projet d’accord de coopération concernant la reconnaissance des cultes, les traitements et pensions des ministres des cultes, les fabriques d'église et les établissements chargés de la gestion du temporel des cultes reconnus
Husson, Jean-François ULg

in Mouvement communal (2003)

Cet article dans Mouvement communal, périodique de l'Union des Villes et Communes de Wallonie, présente ce qui était alors le projet d'accord de coopération entre l'Etat fédéral et les trois Régions ... [more ▼]

Cet article dans Mouvement communal, périodique de l'Union des Villes et Communes de Wallonie, présente ce qui était alors le projet d'accord de coopération entre l'Etat fédéral et les trois Régions belges en matière de temporel des cultes. Cet accord de coopération, officiellement approuvé en 2004, mettait ainsi en oeuvre -en la clarifiant- la réforme de l'Etat de 2001. [less ▲]

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See detailLarge-scale modelling within the PIRENE programme in the Walloon Region of Belgium
Dassargues, Alain ULg

Scientific conference (2003, September 29)

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See detailStructural and functional adaptations to extreme temperatures in psychrophilic, mesophilic, and thermophilic DNA ligases
Georlette, D.; Damien, B.; Blaise, Vinciane ULg et al

in Journal of Biological Chemistry (2003), 278(39), 37015-37023

Psychrophiles, host of permanently cold habitats, display metabolic fluxes comparable to those exhibited by mesophilic organisms at moderate temperatures. These organisms have evolved by producing, among ... [more ▼]

Psychrophiles, host of permanently cold habitats, display metabolic fluxes comparable to those exhibited by mesophilic organisms at moderate temperatures. These organisms have evolved by producing, among other peculiarities, cold-active enzymes that have the properties to cope with the reduction of chemical reaction rates induced by low temperatures. The emerging picture suggests that these enzymes display a high catalytic efficiency at low temperatures through an improved flexibility of the structural components involved in the catalytic cycle, whereas other protein regions, if not implicated in catalysis, may be even more rigid than their mesophilic counterparts. In return, the increased flexibility leads to a decreased stability of psychrophilic enzymes. In order to gain further advances in the analysis of the activity/flexibility/stability concept, psychrophilic, mesophilic, and thermophilic DNA ligases have been compared by three-dimensional-modeling studies, as well as regards their activity, surface hydrophobicity, structural permeability, conformational stabilities, and irreversible thermal unfolding. These data show that the cold-adapted DNA ligase is characterized by an increased activity at low and moderate temperatures, an overall destabilization of the molecular edifice, especially at the active site, and a high conformational flexibility. The opposite trend is observed in the mesophilic and thermophilic counterparts, the latter being characterized by a reduced low temperature activity, high stability and reduced flexibility. These results strongly suggest a complex relationship between activity, flexibility and stability. In addition, they also indicate that in cold-adapted enzymes, the driving force for denaturation is a large entropy change. [less ▲]

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