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See detailMicrolensing in binary systems
Ricci, Davide ULg

(2008)

We present an easy way to simulate and fit light curves of microlensing events for the particular case of binary stellar systems with occultation, using semi-automatic graphical interfaces written in IDL ... [more ▼]

We present an easy way to simulate and fit light curves of microlensing events for the particular case of binary stellar systems with occultation, using semi-automatic graphical interfaces written in IDL language. Gravitational microlensing effects are known to induce light amplifications of the background source and, until now, photometry has been the main technique used to study this phenomenon. A good software, capable to fit multiple parameters of the observed light curve of the microlens event, would allow astronomers to obtain important informations about the physical characteristics of the objects studied. The developpement of such a software is focused to some peculiar case, briefly treated in Sec. 1. The software, written following the parametrization described in Sec. 2, is presented in Sec. 3 and 4. [less ▲]

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See detailAventures historiographiques. Contextes et stratégies d’interprétations métalittéraires
Provenzano, François ULg

in Houdebine, Anne-Marie; Klinkenberg, Jean-Marie (Eds.) Les aventures de l'interprétation (2008)

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See detailA special year for Fusarium Head Blight and associated mycotoxins in Luxembourg
Giraud, Frédéric; Vrancken, Carine; El Jarroudi, Moussa ULg et al

in Toxicology Letters (2008), 180

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See detailComparison of functional residual capacity and static compliance of the respiratory system during a positive end-expiratory pressure (PEEP) ramp procedure in an experimental model of acute respiratory distress syndrome.
Lambermont, Bernard ULg; Ghuysen, Alexandre ULg; Janssen, Nathalie ULg et al

in Critical Care (2008), 12(4), 91

INTRODUCTION: Functional residual capacity (FRC) measurement is now available on new ventilators as an automated procedure. We compared FRC, static thoracopulmonary compliance (Crs) and PaO2 evolution in ... [more ▼]

INTRODUCTION: Functional residual capacity (FRC) measurement is now available on new ventilators as an automated procedure. We compared FRC, static thoracopulmonary compliance (Crs) and PaO2 evolution in an experimental model of acute respiratory distress syndrome (ARDS) during a reversed, sequential ramp procedure of positive end-expiratory pressure (PEEP) changes to investigate the potential interest of combined FRC and Crs measurement in such a pathologic state. METHODS: ARDS was induced by oleic acid injection in six anesthetised pigs. FRC and Crs were measured, and arterial blood samples were taken after induction of ARDS during a sequential ramp change of PEEP from 20 cm H2O to 0 cm H2O by steps of 5 cm H2O. RESULTS: ARDS was responsible for significant decreases in FRC, Crs and PaO2 values. During ARDS, 20 cm H2O of PEEP was associated with FRC values that increased from 6.2 +/- 1.3 to 19.7 +/- 2.9 ml/kg and a significant improvement in PaO2. The maximal value of Crs was reached at a PEEP of 15 cm H2O, and the maximal value of FRC at a PEEP of 20 cm H2O. From a PEEP value of 15 to 0 cm H2O, FRC and Crs decreased progressively. CONCLUSION: Our results indicate that combined FRC and Crs measurements may help to identify the optimal level of PEEP. Indeed, by taking into account the value of both parameters during a sequential ramp change of PEEP from 20 cm H2O to 0 cm H2O by steps of 5 cm H2O, the end of overdistension may be identified by an increase in Crs and the start of derecruitment by an abrupt decrease in FRC. [less ▲]

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See detailDirected evolution on the cold adapted properties of TAB5 alkaline phosphatase
Koutsioulis, D.; Wang, E.; Tzanodaskalaki, M. et al

in Protein Engineering, Design & Selection (2008), 21(5), 319-27

Psychrophilic alkaline phosphatase (AP) from the Antarctic strain TAB5 was subjected to directed evolution in order to identify the key residues steering the enzyme's cold-adapted activity and stability ... [more ▼]

Psychrophilic alkaline phosphatase (AP) from the Antarctic strain TAB5 was subjected to directed evolution in order to identify the key residues steering the enzyme's cold-adapted activity and stability. A round of random mutagenesis and further recombination yielded three thermostable and six thermolabile variants of the TAB5 AP. All of the isolated variants were characterised by their residual activity after heat treatment, Michaelis-Menten kinetics, activation energy and microcalorimetric parameters of unfolding. In addition, they were modelled into the structure of the TAB5 AP. Mutations which affected the cold-adapted properties of the enzyme were all located close to the active site. The destabilised variants H135E and H135E/G149D had 2- and 3-fold higher kcat, respectively, than the wild-type enzyme. Wild-type AP has a complex heat-induced unfolding pattern while the mutated enzymes loose local unfolding transitions and have large shifts of the Tm values. Comparison of the wild-type and mutated TAB5 APs demonstrates that there is a delicate balance between the enzyme activity and stability and that it is possible to improve the activity and thermostability simultaneously as demonstrated in the case of the H135E/G149D variant compared to H135E. [less ▲]

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See detailMultifractality and intermediate statistics in quantum maps
Martin, John ULg; Giraud, O.; Georgeot, B.

in Physical Review. E : Statistical, Nonlinear, and Soft Matter Physics (2008), 77

We study multifractal properties of wave functions for a one-parameter family of quantum maps displaying the whole range of spectral statistics intermediate between integrable and chaotic statistics. We ... [more ▼]

We study multifractal properties of wave functions for a one-parameter family of quantum maps displaying the whole range of spectral statistics intermediate between integrable and chaotic statistics. We perform extensive numerical computations and provide analytical arguments showing that the generalized fractal dimensions are directly related to the parameter of the underlying classical map, and thus to other properties such as spectral statistics. Our results could be relevant for Anderson and quantum Hall transitions, where wave functions also show multifractality. [less ▲]

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See detailOsteonecrosis vertebral y vertebroplastia percutanea.
Rossello, Lluis; Palliso, Francesc; Ferrer, Jesus et al

in Reumatologia clinica (2008), 4(4), 162-5

Vertebral osteonecrosis is characterized by the presence of the intravertebral vacuum phenomenon. It is a relatively uncommon disease and although it may be caused by different pathologies, the most ... [more ▼]

Vertebral osteonecrosis is characterized by the presence of the intravertebral vacuum phenomenon. It is a relatively uncommon disease and although it may be caused by different pathologies, the most frequent cause is posttraumatic. The explanation for the presence of intravertebral gas is not known completely. We present the case of a 74-year-old patient who after suffering a vertebral traumatism, to complain of intense vertebral pain. A simple radiological study, CT scan, and magnetic resonance confirmed the presence of intravertebral vacuum phenomenon. We studied this radiological sign and then commented on its evolution after percutaneous vertebroplasty. [less ▲]

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See detailItinéraire géologique et paleontologique dans la carrière d'Ampsin (Amay, Belgique)
Barchy, Laurent; Marion, Jean-Marc ULg; Poty, Edouard ULg

Diverse speeche and writing (2008)

Close to the museum "Master of the Fire" at Ampsin (Amay, Belgium), an abandoned quarry is used to present both the local and regional geologic history, and the fauna and flora related to the site. For ... [more ▼]

Close to the museum "Master of the Fire" at Ampsin (Amay, Belgium), an abandoned quarry is used to present both the local and regional geologic history, and the fauna and flora related to the site. For all. [less ▲]

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See detailSelection of the most efficient wavelength bands for discriminating weeds from crop
Piron, Alexis ULg; Leemans, Vincent ULg; Kleynen, O. et al

in Computers & Electronics in Agriculture (2008), 62(2), 141-148

The aim of this study was to select the best combination of filters for detecting various weed species located within carrot rows. In-field images were taken under artificial lighting with a multispectral ... [more ▼]

The aim of this study was to select the best combination of filters for detecting various weed species located within carrot rows. In-field images were taken under artificial lighting with a multispectral device consisting of a black and white camera coupled with a rotating wheel holding 22 interference filters in the VIS-NIR domain. Measurements were performed over a period of 19 days, starting 1 week after crop emergence (early weeding can increase yields) and seven different weeds species were considered. The selection of the best filter combination was based on a quadratic discriminant analysis. The best combination of filters included three interference filters, respectively centred on 450, 550 and 700 nm. With this combination, the overall classification accuracy (CA) was 72%. When using only two filters, a slight degradation of the CA was noticed. When the classification results were reported on field images, a systematic misclassification of carrot cotyledons appears. Better results were obtained with a more advanced growth stage. (c) 2007 Elsevier B.V. All rights reserved. [less ▲]

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See detailTerritoire en mutation
Dawans, Stéphane ULg

Article for general public (2008)

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See detailDéveloppement rural et coopération interuniversitaire
Dang Vu, Binh; Vu Dinh, Ton; Lebailly, Philippe ULg et al

Conference (2008)

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See detailAdiabatic decoupling of the reaction coordinate
Lorquet, Jean-Claude ULg

in International Journal of Quantum Chemistry (2008), 108(10), 1629-1636

When the dynamics is constrained by adiabatic invariance, a reactive process can be described as a one-dimensional motion along the reaction coordinate in an effective potential. This simplification is ... [more ▼]

When the dynamics is constrained by adiabatic invariance, a reactive process can be described as a one-dimensional motion along the reaction coordinate in an effective potential. This simplification is often valid for central potentials and for the curved harmonic valley studied in the reaction path Hamiltonian model. For an ionolecule reaction, the action integral < Pθ> = (1/2π){clockwise contour integral}P θdθ is an adiabatic invariant. The Poisson bracket of <Pθ>2 with Hamiltonians corresponding to a great variety of long-range electrostatic interactions is found to decrease with the separation coordinate r, faster than the corresponding potential. This indicates that the validity of the adiabatic approximation is not directly related to the shape of the potential energy surface. The leading role played by the translational momentum is accounted for by Jacobi's form of the least action principle. However, although the identification of adiabatic regions by this procedure is limited to a specific range of coordinate configurations, equivalent constraints must persist all along the reaction coordinate and must operate during the entire reaction, as a result of entropy conservation. The study of the translational kinetic energy released on the fragments is particularly appropriate to detect restrictions on energy exchange between the reaction coordinate and the bath of internal degrees of freedom. ©2008 Wiley Periodicals, Inc. [less ▲]

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See detailOwl or lark? Stroop-related cerebral activity is modulated by time of day and chronotype
Schmidt, Christina ULg; Collette, Fabienne ULg; Sterpenich, Virginie et al

in Journal of Sleep Research (2008), 17(Suppl. 1),

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See detailMeiotic Analysis of the Germplasm of three Medicinal Species from the Asteraceae Family
Olkoski, D; Laughinghouse IV, Haywood ULg; Silva, ACF et al

in Ciencia Rural (2008), 38(6), 1777-1780

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See detailLe cas clinique du mois. Un cas rare d'épanchement pleural unilatéral: le syndrome d'hyperstimulation des ovaires.
Barile, D.; Bataille, Yoann ULg; Duysinx, Bernard ULg et al

in Revue Médicale de Liège (2008), 63(7-8), 474-9

Ovarian hyperstimulation syndrome is the most severe iatrogenic complication of fertilization modern methods. This syndrome is characterized by a massive cystic ovarian enlargement associated with an ... [more ▼]

Ovarian hyperstimulation syndrome is the most severe iatrogenic complication of fertilization modern methods. This syndrome is characterized by a massive cystic ovarian enlargement associated with an acute body fluid shift. Ascite is the most frequent manifestation of this syndrome. In some rare cases ovarian hyperstimulation syndrome is complicated by massive unilateral pleural effusion without ascite. We describe the case of a 36 year old woman who developed a massive unilateral pleural effusion without ascite. An ovarian hyperstimulation syndrome was diagnosed. Chest tube drainage improved patient parameters and symptoms. We discuss the diagnostic approach of pleural effusions. [less ▲]

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See detailRaconter la recherche-intervention, retour sur trois opérations de gestion de la biodiversité
Petit, S.; Fleury, P.; Michel, V. et al

in Natures Sciences Sociétés (2008), 16

L'article se fonde sur un matériau peu courant : des récits de projets de gestion de la biodiversité associant les mondes de l'agriculture et de l'environnement. Trois situations de recherche-intervention ... [more ▼]

L'article se fonde sur un matériau peu courant : des récits de projets de gestion de la biodiversité associant les mondes de l'agriculture et de l'environnement. Trois situations de recherche-intervention sont ainsi analysées grâce aux concepts de la science en action. Elles mettent en évidence les caractéristiques de ces collectifs, les connaissances qu'ils mobilisent, ainsi que les outils d'intervention qu'ils construisent dans des processus mêlant recherche et action. La biodiversité dont il est question ici n'est ni celle du ministère dont les collectifs constitués autour de questions inédites se donnent la charge. En les suivant, grâce aux récits qu'en font les chercheurs, nous analysons les ressorts de la recherche-intervention, comparativement à une recherche plus classique. [less ▲]

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See detailContributions of a 3D numerical environment for architectural sketches.
Mayeur, A.; Darses, F.; Leclercq, Pierre ULg

in Lecture Notes in Computer Science (2008)

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See detailAntitumor and anti-angiogenic effects of aplidin in the 5T33MM model, syngeneic model of multiple myeloma
Caers, Jo ULg; De Raeve, Hendrik; Lepage, Doreen et al

in British Journal of Cancer (2008), 98(12), 1966-74

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See detailSystemic resistance and lipoxygenase-related defence response induced in tomato by Pseudomonas putida strain BTP1.
Akram, Adam; Ongena, MARC ULg; Duby, Franceline et al

in BMC Plant Biology (2008), 8

BACKGROUND: Previous studies showed the ability of Pseudomonas putida strain BTP1 to promote induced systemic resistance (ISR) in different host plants. Since ISR is long-lasting and not conducive for ... [more ▼]

BACKGROUND: Previous studies showed the ability of Pseudomonas putida strain BTP1 to promote induced systemic resistance (ISR) in different host plants. Since ISR is long-lasting and not conducive for development of resistance of the targeted pathogen, this phenomenon can take part of disease control strategies. However, in spite of the numerous examples of ISR induced by PGPR in plants, only a few biochemical studies have associated the protective effect with specific host metabolic changes. RESULTS: In this study, we showed the protective effect of this bacterium in tomato against Botrytis cinerea. Following treatment by P. putida BTP1, analyses of acid-hydrolyzed leaf extracts showed an accumulation of antifungal material after pathogen infection. The fungitoxic compounds thus mainly accumulate as conjugates from which active aglycones may be liberated through the activity of hydrolytic enzymes. These results suggest that strain BTP1 can elicit systemic phytoalexin accumulation in tomato as one defence mechanism. On another hand, we have shown that key enzymes of the lipoxygenase pathway are stimulated in plants treated with the bacteria as compared with control plants. Interestingly, this stimulation is observed only after pathogen challenge in agreement with the priming concept almost invariably associated with the ISR phenomenon. CONCLUSION: Through the demonstration of phytoalexin accumulation and LOX pathway stimulation in tomato, this work provides new insights into the diversity of defence mechanisms that are inducible by non-pathogenic bacteria in the context of ISR. [less ▲]

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