The rotational Predissociation of HeH+: Energy and Lifetime measurements.

in Chemical Physics (1976), 15

Relative lifetimes and energies above the dissociation limit have been determined for the rotational predissociation of several quasibound levels of the X1Sigma+ state of 4HeH+. In particular the ... [more ▼]

Relative lifetimes and energies above the dissociation limit have been determined for the rotational predissociation of several quasibound levels of the X1Sigma+ state of 4HeH+. In particular the lifetimes are very sensitive to the shape of the potential energy curve. These measurements are used to discriminate between two ab initio potential curves which differ by only 0.00004 a.u. (about 1 meV). Using the lifetime data, relative population factors were determined for the observed levels. [less ▲]

Rotational splittings for slow to moderate rotators. Latitudinal dependence or higher order effects in Ω?

in Astronomy and Astrophysics (2012), 542(A99),

Context. The unprecedented photometric quality reached by the CoRoT and Kepler space missions opens new prospects for studying stellar rotation. Information about the rotation rate is contained on the one ... [more ▼]

Context. The unprecedented photometric quality reached by the CoRoT and Kepler space missions opens new prospects for studying stellar rotation. Information about the rotation rate is contained on the one hand in the low frequency part of the power spectra, where signatures of nonuniform surface rotation are expected, and on the other hand in the frequency splittings induced by the internal rotation rate. Aims: We wish to figure out whether the differences between the seismic rotation period determined by a mean rotational splitting, and the rotation period measured from the low frequency peak in the Fourier spectrum - observed for some of CoRoT's targets - can provide constraints on the rotation profile. Methods: For uniform moderate rotators,perturbative corrections to second and third order in terms of the rotation angular velocity Ω, must not be neglected. These effects, in particular, may mimic differential rotation. We apply our perturbation method to evaluate mode frequencies that are accurate up to Ω3 for uniform rotation. The effects of latitudinal dependence are calculated in the linear approximation. Numerical results were obtained for selected models of the upper and lower parts of the main sequence. For the latitudinal dependence, we adopt two types of rotation profile: one with rotation uniform in depth, and one with a solar-like tachocline. Results: Deviations from the first-order splitting for a uniformly rotating star can be due to both cubic-order effects of rotation and latitudinal differential rotation. In models of β Cephei pulsators, which represent upper main sequence stars, third order effects become comparable to that of a horizontal shear similar to the solar one at rotation rates well below the breakup values. These nonlinear effects are strongly mode-dependent. We show how a clean signature of the latitudinal shear may be extracted. Our models of two CoRoT target HD 181906 and HD 181420, which are solar-like pulsators, represent lower main sequence objects. These are slow rotators and nonlinear effects in splittings are accordingly small. We use data for one low frequency peak and one splitting of a dipolar mode to constrain the rotation profile in HD 181420 and HD 181906. Conclusions: The relative influences of the two effects strongly depend on the type of oscillation modes excited in the star and the magnitude of the rotation rate. Given the mean rotational splitting and the frequency of a spot signature, it is possible to distinguish between the two hypotheses. In the case of differential rotation in latitude, we propose a method to determine the type of rotation profile and a range of values for the shear. [less ▲]

Rotenoid content and in vitro acaricidal activity of Tephrosia vogelii leaf extract on the tick Rhipicephalus appendiculatus

in Veterinary Parasitology (2012), 190(1-2), 204-209

Rottlerin inhibits human T cell responses

in Biochemical Pharmacology (2007), 73(4), 515-525

Rottlerin is a pharmacological inhibitor of protein kinase C (PKC) theta, a novel PKC selectively expressed in T lymphocytes. PKC theta is known to regulate T cell receptor (TCR)/CD28 signalling pathways ... [more ▼]

Rottlerin is a pharmacological inhibitor of protein kinase C (PKC) theta, a novel PKC selectively expressed in T lymphocytes. PKC theta is known to regulate T cell receptor (TCR)/CD28 signalling pathways in T lymphocytes, but the impact of PKC theta inhibition on human T cell responses remains undefined. In this work, we describe the effects of rottlerin on the responses of CD4+ and CD8+ human T lymphocytes upon polyclonal activation. We observed a dose-dependent inhibition of CD4+ and CD8+ T cell proliferation in response to anti-CD3/antiCD28 antibodies stimulation in the presence of rottlerin. This inhibition was associated with impaired CD25 expression and decreased interleukin (IL)-2 production in activated T cells. In contrast, rottlerin did not alter IL-2-induced T cell proliferation. Furthermore, we demonstrated that rottlerin blocked interferon (IFN) gamma, IL-10 and IL-13 mRNA expression in TCR/CD28 activated CD4+ T cells. These findings place rottlerin as a potent immunosuppressive agent for the development of novel therapies in T cell mediated immune disorders. (c) 2006 Elsevier Inc. All rights reserved. [less ▲]

Rouge Métal : 100 ans d’histoire des métallos liégeois de la FGTB

in Institut d'Histoire ouvrière, économique et sociale (IHOES) (Ed.) Rouge Métal : 100 ans d’histoire des métallos liégeois de la FGTB (2006)

L’ouvrage retrace les principaux jalons qui ont rythmé les cent ans de la Fédération syndicale des Métallurgistes de Liège – FGTB, depuis sa création en 1905 jusqu’à nos jours. Au travers de l’évocation ... [more ▼]

L’ouvrage retrace les principaux jalons qui ont rythmé les cent ans de la Fédération syndicale des Métallurgistes de Liège – FGTB, depuis sa création en 1905 jusqu’à nos jours. Au travers de l’évocation des figures ayant marqué la Fédération et des principaux mouvements et conflits qui ont émaillé son histoire, Rouge Métal met en évidence l’apport de la Fédération aux revendications syndicales fondamentales, aux grands mouvements sociaux de l’histoire ouvrière wallonne et au fédéralisme. L’ouvrage offre également un aperçu de l’évolution de la Fédération en termes d’organisation interne (structure, effectifs, formation des militants…) et veille à replacer son action dans le contexte économique et social. [less ▲]

Roughness analysis on powders using mathematical morphology

in Acta Stereologica (1992), 11(Suppl. 1), 533-538

Rouille brune du blé, un modèle pour évaluer les risques

in Phytoma-la défense des végétaux (2010), 637

L’article présente un outil de prévision de la rouille brune au G.-D. de Luxembourg. De 2000 à 2003, cette maladie apparaissait à la fin de l’épiaison, mais depuis 2003, elle apparaît de plus en plus tôt ... [more ▼]

L’article présente un outil de prévision de la rouille brune au G.-D. de Luxembourg. De 2000 à 2003, cette maladie apparaissait à la fin de l’épiaison, mais depuis 2003, elle apparaît de plus en plus tôt (GS45 stade gonflement). Cette apparition précoce est probablement liée à des températures printanières supérieures par rapport à la normale 1971-2000. Une analyse des données météorologiques nocturnes et des données d’observation de la maladie sur quatre sites expérimentaux (Everlange, Christnach, Burmerange et Reuler) entre 2000 et 2003 a révélé une forte corrélation positive entre la prédiction de la maladie basée sur le critère d’au moins 12 heures consécutives avec une température comprise entre 8 et 16°C et une humidité supérieure à 60% et la maladie observée sur la F1 (R = 0.93 ; P < 0.05) et sur la F2 (R = 0.87 ; P < 0.05). Les sorties de ce modèle qui a été développé sur base d’une approche stochastique ont été utilisées dans les bulletins d’avertissements diffusés conjointement par le Centre de Recherche Public – Gabriel Lippmann et l’Université de Liège-Campus d’Arlon à partir de 2004. La mise en application de ce modèle a montré un taux de réussite oscillant entre 80 et 85% pour la simulation de la rouille brune au G.-D. de Luxembourg. L’effort se poursuit pour spatialiser les sorties du modèle sur tout le territoire luxembourgeois et faciliter son utilisation par tous les vulgarisateurs agricoles. [less ▲]

La rouille suisse du Douglas

in Silva Belgica (2011), 6/2011

Round Table Conference on Mediators of Sepsis--Brussels, Belgium, March 21-23, 1992

in Intensive Care Medicine (1994), 20(3), 238-41

Round table discussion on glucocorticoid replacement therapy

Scientific conference (2009, April 27)