References of "2001"
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See detailAuroral Precipitation during the Bastille Day Storm Recovery
Immel, T. J.; Mende, S. B.; Frey, H. U. et al

Conference (2001, December 01)

The recovery period following the geomagnetic storm of July 15-16, 2000 is marked by rapid changes in auroral morphology and brightness in the sunlit hemisphere. These observations are made by the FUV and ... [more ▼]

The recovery period following the geomagnetic storm of July 15-16, 2000 is marked by rapid changes in auroral morphology and brightness in the sunlit hemisphere. These observations are made by the FUV and EUV imagers aboard the IMAGE satelite. Clear signatures of magnetospheric convection are observed in the motion of the auroral forms, indicating sunward convection of plasma in the polar cap under the strong northward component of the IMF. Precipitation is also observed equatorward of the auroral oval on the dayside in large diffuse arcs. Unlike previously observed detached proton arcs, this precipitation appears to have a significant electron component. Determination of the characteristic energies and fluxes of electrons and protons requires the proper removal of FUV airglow emissions, which in this case have been strongly affected by the recent magnetic activity. EUV images provide a very clear signature of these events, with practically no airglow contamination. With proper modeling, these EUV images could provide improvements to the characterization of the magnetospheric energy input to the thermosphere and ionosphere from space-based imaging. [less ▲]

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See detailA novel approach for extracting time-delays from lightcurves of lensed quasar images
Burud, I.; Magain, Pierre ULg; Sohy, Sandrine ULg et al

in Astronomy and Astrophysics (2001), 380

We present a new method to estimate time delays from light curves of lensed quasars. The method is based on chi [SUP]2[/SUP] minimization between the data and a numerical model light curve. A linear ... [more ▼]

We present a new method to estimate time delays from light curves of lensed quasars. The method is based on chi [SUP]2[/SUP] minimization between the data and a numerical model light curve. A linear variation can be included in order to correct for slow long-term microlensing effects in one of the lensed images. An iterative version of the method can be applied in order to correct for higher-order microlensing effects. The method is tested on simulated light curves. When higher-order microlensing effects are present, the time delay is best constrained with the iterative method. Analysis of a published data set for the lensed double Q 0957+561 yields results in agreement with other published estimates. [less ▲]

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See detailTwo types of localized auroral UV emission on the dayside
Frey, H. U.; Mende, S. B.; Immel, T. J. et al

Conference (2001, December 01)

The FUV instrument on IMAGE frequently observes localized ultraviolet emission on the high latitude dayside, poleward of the normal auroral oval. There are two different types of these localized emissions ... [more ▼]

The FUV instrument on IMAGE frequently observes localized ultraviolet emission on the high latitude dayside, poleward of the normal auroral oval. There are two different types of these localized emissions. One is especially distinct in the observations of Doppler shifted Lyman alpha emission from proton precipitation. This type occurs during northward IMF and high solar wind dynamic pressure. We interpret this emission as the optical signature of proton precipitation into the cusp after lobe reconnection at the magnetopause. The second type of localized emission is visible in the wide-band (WIC) and oxygen (SI13) imagers, but is absent in the proton imager. This emission occurs during northward IMF but very low solar wind density and dynamic pressure. We interpret this emission as the optical signature of electron acceleration after reconnection. [less ▲]

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See detailThe B-type variable HD 131120 modelled by rotational modulation
Briquet, Maryline ULg; De Cat, P.; Aerts, C. et al

in Astronomy and Astrophysics (2001), 380

We present ground-based multi-colour Geneva photometry and high-resolution spectra of the variable B-type star HD 131120. All sets of data reveal a monoperiodic star with a period of 1.569 days. We ... [more ▼]

We present ground-based multi-colour Geneva photometry and high-resolution spectra of the variable B-type star HD 131120. All sets of data reveal a monoperiodic star with a period of 1.569 days. We compare the variability of the star with a non-radial g-mode pulsation model and with a rotational modulation model. The latter model appears to be the best explanation for the observed line-profile variations of the star. Moreover, contrary to the pulsational model, it is able to reproduce the behaviour of the first three moments of the Si and He lines as well as the large variability of their equivalent width. We therefore remove the star from the list of new Slowly Pulsating B stars found from Hipparcos data. Based on observations obtained with the Swiss photometric telescope and ESO's CAT/CES telescope, both situated at La Silla, Chile. [less ▲]

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See detailSpectroscopic monitoring of 10 new northern slowly pulsating B star candidates discovered from the HIPPARCOS mission
Mathias, P.; Aerts, C.; Briquet, Maryline ULg et al

in Astronomy and Astrophysics (2001), 379

A one-year follow-up campaign of high-resolution, high-signal-to-noise spectroscopy for 10 candidate slowly pulsating B stars, which were discovered from the HIPPARCOS astrometric mission, shows that all ... [more ▼]

A one-year follow-up campaign of high-resolution, high-signal-to-noise spectroscopy for 10 candidate slowly pulsating B stars, which were discovered from the HIPPARCOS astrometric mission, shows that all stars exhibit line-profile variability. From our data, and from the HIPPARCOS photometry, we conclude that all but one of the targets provide evidence of multiperiodicity, with periods of the order of days, confirming their pulsational nature. Thus they are confirmed slowly pulsating B stars. We summarize the pulsation periods and Q-values and select the most interesting targets for very-long-term follow-up observations with the goal of performing asteroseismology. Based on observations obtained at the Observatoire de Haute-Provence. [less ▲]

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See detailSimultaneous Observation of Magnetospheric Neutral Atoms and Proton Aurora
Mende, S. B.; Frey, H. U.; Immel, T. J. et al

in Eos (2001), 42

Data from the High Energy Neutral Atom (ENA) and the far ultraviolet (FUV) imagers on IMAGE were compared for a six hour period during which a reasonably intense substorm occurred. The substorm presented ... [more ▼]

Data from the High Energy Neutral Atom (ENA) and the far ultraviolet (FUV) imagers on IMAGE were compared for a six hour period during which a reasonably intense substorm occurred. The substorm presented is typical of a substorm expansive phase showing that while the total electron precipitation suddenly increase one whole order of magnitude, the protons increase only about 50%. In principle ENA images represent the trapped fluxes in the magnetosphere while the proton aurora measured by the FUV SI12 instrument represents the precipitating component. At substorm onset the increase in intensity of the auroral protons and electrons is very sudden while the intensification of the ENA-s coming from regions of L<6 is much more gradual. The intensification of the precipitating electrons is relatively short lived ( ~ 10 minutes) while the ENA enhancements are long lived (almost a whole hour). Just prior to the substorm expansive phase (in the growth phase) the precipitated proton and electron fluxes encounter a minimum while the ENA-s show a slight growth. [less ▲]

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See detailFonctionnement et performances des couloirs oscillants à glissement
Debongnie, Jean-François ULg; Masset, Luc ULg

in European Journal of Mechanical and Environmental Engineering (2001), 46(4), 243-254

This paper is devoted to the study of the efficiency of an oscillating trough for any value of the frequency. It is found that pure slipping or mixed cycles may occur, the latter comprising sticking ... [more ▼]

This paper is devoted to the study of the efficiency of an oscillating trough for any value of the frequency. It is found that pure slipping or mixed cycles may occur, the latter comprising sticking periods. The results of the present analysis concern the cyclic displacement, the mean velocity and the dissipated power. [less ▲]

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See detailAffections bénignes et radiothérapie : une enquête de la pratique en Belgique. Peer review de radiothérapie de BelgiqueBenign disease in radiation therapy: a survey in Belgium.
Vanderick, JEAN ULg; Baudouin; Deneufbourg, Jean-Marie ULg et al

in Cancer Radiotherapie (2001), 5(6), 766-9

n 1996 and 2000, a survey of radiation practice in Belgium was performed by sending a questionnaire to the different centers asking their opinion and number of patients treated. There was a great ... [more ▼]

n 1996 and 2000, a survey of radiation practice in Belgium was performed by sending a questionnaire to the different centers asking their opinion and number of patients treated. There was a great similarity between the two surveys both for indications and total number of patients irradiated. For the most common indications (prevention of cheloids, heterotopic bone formation, hyperthyroidy ophtalmopathy), there was a trend to use similar radiation technique following recent publications. In contrast, if the number of cases of macular degeneration is declining, the prevention of vessels restenosis is becoming more and more an indication. [less ▲]

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See detailPrésentation comparative et thématique des politiques de défense des Etats membres de l'UE
Dumoulin, André ULg; Mathieu, Raphaël; Metten, Vincent

in Sécurité et stratégie (2001), (68), 188

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See detailDe bijdrage van de organisatiesociologie tot het begrijpen van het functioneren van justitie
Schoenaers, Frédéric ULg

in toekomst van rechtssociologie in het justitiële beleid (2001, December)

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See detailGlobal analysis of a continuous-time flow whith computes time-optimal switchings
Grognard, F.; Sepulchre, Rodolphe ULg

in Proceedings of the 40th IEEE Conference on Decision and Control (2001, December)

The minimum-time bounded control of linear systems is generically bang-bang and the number of switchings does not exceed the dimension of the system if the eigenvalues of the system matrix are real. This ... [more ▼]

The minimum-time bounded control of linear systems is generically bang-bang and the number of switchings does not exceed the dimension of the system if the eigenvalues of the system matrix are real. This paper proposes a synthesis method for such problems based on dynamical systems that "compute" the optimal sequence of switching times. [less ▲]

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See detailComparative In Vitro Activity of Amphotericine B, Itraconazole, Voriconazole and Posaconazole against Aspergillus fumigatus
Hayette, Marie-Pierre ULg; Amadore, Agatha; Seidel, Laurence ULg et al

Poster (2001, December)

Background. New azoles have been successfully used as treatment of invasive aspergillosis. The purpose of this study was to compare the in vitro activity of posaconazole (Posa) with that of amphotericin B ... [more ▼]

Background. New azoles have been successfully used as treatment of invasive aspergillosis. The purpose of this study was to compare the in vitro activity of posaconazole (Posa) with that of amphotericin B (AmB), itraconazole (Itra) and voriconazole (Vor) against A. fumigatus isolates according to NCCLS method (M38-P), and to compare visual and spectrophotometric readings for MIC determination. Methods. A total of 106 A. fumigatus isolates were selected as follows: 88 clinical isolates from colonized patients, 18 from patients with invasive aspergillosis and 7 environmental isolates. Their in vitro susceptibility was evaluated by the NCCLS microdilution method (M38-P) in RPMI 1640 medium. Determination of results was made by visual and spectrophotometric readings (630 nm) after 48 hours incubation at 35 degreesC. Three A. fumigatus reference strains (IHEM 5734, 6149 and 13935) were included as control. Results. 1. Geometric mean MICs/MIC90 (microg/ml) obtained by visual reading were respectively 0.66/1 (AmB), 0.37/0.5 (Itra), 0.27/0.5 (Vor) and 0.02/0.03 (Posa). 2. MIC values were comparable by spectrophotometric and by visual readings for all antifungal agents tested (p>.05) and did not depend on the isolates origin (p>.05). 3. Posaconazole had the lowest MICs (p< 0.001). 4. The itraconazole-resistant reference strain did not give cross resistance with voriconazole and posaconazole. CONCLUSIONS: Among azoles, posaconazole had a better in vitro activity against A. fumigatus than did voriconazole or itraconazole. Spectrophotometric reading could replace the less standardized visual reading for NCCLS microdilution method and MIC values obtained were comparable among all A. fumigatus isolates. [less ▲]

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See detailImportance of soft solution processing for advanced BaZrO3 materials
Robertz, B.; Boschini, Frédéric ULg; Cloots, Rudi ULg et al

in International Journal of Inorganic Materials (2001), 3(8), 1185-1187

Barium zirconate is an interesting material for refractory applications as well as a good substrate for the manufacturing of high temperature superconductors. However, its solid state synthesis requires ... [more ▼]

Barium zirconate is an interesting material for refractory applications as well as a good substrate for the manufacturing of high temperature superconductors. However, its solid state synthesis requires high temperature and provides inhomogeneous powder with a broad particle size distribution. In order to avoid these disadvantages, soft solution routes are of growing importance in the ceramic powder synthesis. Precipitation. decomposition of precursors, combustion techniques offer alternative ways to the solid state method. Advantages of these are a lower calcination temperature, production of homogeneous and fine monodisperse powders. The obtained powders have been characterised by XRD, IR, SEM and DTA/TG analysis. The influence of the synthesis conditions on the properties of BaZrO3 has been studied. (C) 2001 Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailInduced sputum - Comparison between isotonic and hypertonic saline solution inhalation in patients with asthma
Cataldo, Didier ULg; Foidart, Jean-Michel ULg; Lau, L. et al

in CHEST (2001), 120(6), 1815-1821

Background: Sputum induction by hypertonic saline solution inhalation is widely used to study airways secretions in patients with asthma. However, hypertonic saline solution is a potent indirect ... [more ▼]

Background: Sputum induction by hypertonic saline solution inhalation is widely used to study airways secretions in patients with asthma. However, hypertonic saline solution is a potent indirect bronchoconstrictor. Study objectives: We studied the validity of isotonic saline solution (0.9%) inhalation as a means to induce sputum by comparing it to hypertonic saline solution (4.5%) inhalation. Patients: Sixteen patients with moderate-to-severe asthma reporting a clinical history of mucus hypersecretion. Methods: Subjects underwent sputum induction twice at 1-week intervals. Saline solution (hypertonic or isotonic) was inhaled For three periods of 5 min. The parameters assessed in sputum samples were cell counts, sodium, eosinophil cationic protein (ECP), and albumin concentrations, osmolality, and pro-matrix metalloproteinase (MMP)-9 activity by zymography. Results: The maximal fall in peak expiratory flow during sputum induction was greater after inhalation of hypertonic saline solution than after inhalation of isotonic saline solution (p < 0.01). Each subject produced analyzable sputum on both visits. There were no statistically significant differences in total and differential sputum cell counts, and the reproducibility coefficients were high for eosinophils and neutrophils when comparing the two methods. Likewise, sputum levels of ECP and albumin as well as sputum pro-MMP-9 activity were not different between the two methods, and were highly reproducible as shown by high intraclass coefficients (Ri) of correlation (0.72, 0.74, and 0.77 for ECP, albumin, and pro-MMP-9, respectively). Sputum sodium concentrations and osmolality were higher after inhalation of hypertonic saline solution (p < 0.05). Conclusion: In patients with moderate-to-severe asthma reporting a clinical history of mucus hypersecretion, inducing sputum by isotonic or hypertonic saline solution inhalation leads to comparable results in eosinophil and neutrophil cell counts and fluid phase mediators/proteins. [less ▲]

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See detailImpact studies and water management with WolfHydro : a new physically based hydrological solver
Archambeau, Pierre ULg; Mouzelard, Thibaut; Erpicum, Sébastien ULg et al

in International Symposium on Environmental Hydraulics (2001, December)

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See detailSpa, ensemble architectural du parc de Sept-Heures [...]
Heins, Pascal ULg

in Histoire et Archéologie spadoises (2001), 108(32), 176-184

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See detailSystemic inflammatory response to cardiac surgery: does female sex really protect?
SEGHAYE, Marie-Christine ULg; Qing, M.; von Bernuth, G.

in Critical Care (2001), 5(6), 280-2

Sex hormones have important interactions with the immune system and modulate the inflammatory response. In this regard, oestrogen inhibits the transcription of proinflammatory cytokines and confers tissue ... [more ▼]

Sex hormones have important interactions with the immune system and modulate the inflammatory response. In this regard, oestrogen inhibits the transcription of proinflammatory cytokines and confers tissue protection in experimental models. On the basis of this evidence, Trotter et al. in this issue of Critical Care addressed the question of whether, in children, female sex would protect against the deleterious effects of cardiac operations with cardiopulmonary bypass by providing a favourable anti-inflammatory cytokine balance. The observations made in that study suggest sex-related immunomodulation and organ protection during cardiac surgery in the paediatric population. Prospective trials conducted in large series, including sex hormone determination in neonates, infants and children with congenital cardiac defects, are necessary to test this hypothesis. The verification of sex-related intraoperative organ protection would provide new opportunities for preventing the uncontrolled systemic inflammatory response that may occur during cardiac surgery. [less ▲]

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See detailMulticriteria and multiactors interactive tool aiding to sketch the building envelope during the first stages of the architectural design, with objective of cost and energy performances
Hauglustaine, Jean-Marie ULg

in Performance of Exterior Envelopes of Whole Buildings VIII: Integration of Building Envelopes (2001, December)

The present study explores a Multiple Criteria Decision Aid (MCDA) procedure, an aid to help project authors optimise the building envelope during the sketch design, where a significant number of choices ... [more ▼]

The present study explores a Multiple Criteria Decision Aid (MCDA) procedure, an aid to help project authors optimise the building envelope during the sketch design, where a significant number of choices are fixed, having a determining impact on the future building cost and use. The objective of the design method is the respect of building costs – for the building construction and use – and the energy performance improvement. An interactive tool has been developed within multicriteria and multiactors context. In order to improve the architectural response to the client’s and regulation requirements, it gives decision-making aids to: - the project authors: in making up the project architectural forces, in accordance with the actors’ objectives; - the client: in reaching his objectives of costs, building duration, comfort and functionality, while serenely assuming his responsibilities related to his building energy and environment performances. The design tool is organised in two linked modules, any actor may go in any module in any time: - the first one manages parameters describing the project requirements; - the graphic module allows to draw the sketch; it calculates geometric parameter values that it puts back in the first module. Permanently informed on cost and energy performances, the user can any time search for optimal scenario giving best satisfaction or compromise: he has at his disposal at lot of graphs illustrating the performance sensitivity to parameter variation, as well as an optimisation procedure using a genetic algorithm to find the most efficient parameter set. The software is organised to manage new building projects of housings, schools and offices (small to medium size projects). [less ▲]

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