Auroral Precipitation during the Bastille Day Storm Recovery

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 ▲]

Two types of localized auroral UV emission on the dayside

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 ▲]

The B-type variable HD 131120 modelled by rotational modulation

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 ▲]

Fonctionnement et performances des couloirs oscillants à glissement

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 ▲]

De bijdrage van de organisatiesociologie tot het begrijpen van het functioneren van justitie

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

Comparative In Vitro Activity of Amphotericine B, Itraconazole, Voriconazole and Posaconazole against Aspergillus fumigatus

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 ▲]

Importance of soft solution processing for advanced BaZrO3 materials

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 ▲]

Induced sputum - Comparison between isotonic and hypertonic saline solution inhalation in patients with asthma

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 ▲]

Spa, ensemble architectural du parc de Sept-Heures [...]

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

Systèmes d'assurance de qulaité dans le cadre des laboratoires de chimie médicale

Conference (2001, December)