References of "Leroy, B"
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See detailDiscovery of a magnetic field in the CoRoT hybrid B-type pulsator HD 43317
Briquet, Maryline ULg; Neiner, C.; Leroy, B. et al

in Astronomy and Astrophysics (2013), 557

Context. A promising way of testing the impact of a magnetic field on internal mixing (core overshooting, internal rotation) in main-sequence B-type stars is to perform asteroseismic studies of a sample ... [more ▼]

Context. A promising way of testing the impact of a magnetic field on internal mixing (core overshooting, internal rotation) in main-sequence B-type stars is to perform asteroseismic studies of a sample of magnetic pulsators. <BR /> Aims: The CoRoT satellite revealed that the B3IV star HD 43317 is a hybrid SPB/β Cep-type pulsator that has a wealth of pulsational constraints on which one can perform a seismic modelling, in particular, probing the extent of its convective core and mixing processes. Moreover, indirect indicators of a magnetic field in the star were observed: rotational modulation due to chemical or temperature spots and X-ray emission. Our goal was to directly investigate the field in HD 43317 and, if it is magnetic, to characterise it. <BR /> Methods: We collected data with the Narval spectropolarimeter installed at Télescope Bernard Lyot (TBL, Pic du Midi, France) and applied the least-squares deconvolution technique to measure the circular polarisation of the light emitted from HD 43317. We modelled the longitudinal field measurements directly with a dipole. <BR /> Results: Zeeman signatures in the Stokes V profiles of HD 43317 are clearly detected and rotationally modulated, which proves that this star exhibits an oblique magnetic field. The modulation with the rotation period deduced from the CoRoT light curve is also confirmed, and we found a field strength at the poles of about 1 kG. Our result must be taken into account in future seismic modelling work of this star. Based on observations obtained using the Narval spectropolarimeter at the Observatoire du Pic du Midi (France), which is operated by the Institut National des Sciences de l'Univers (INSU). [less ▲]

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See detailStochastic gravito-inertial modes discovered by CoRoT in the hot Be star HD 51452
Neiner, C.; Floquet, M.; Samadi, R. et al

in Astronomy and Astrophysics (2012), 546

Context. Be stars are rapidly rotating stars with a circumstellar decretion disk. They usually undergo pressure and/or gravity pulsation modes excited by the κ-mechanism, i.e. an effect of the opacity of ... [more ▼]

Context. Be stars are rapidly rotating stars with a circumstellar decretion disk. They usually undergo pressure and/or gravity pulsation modes excited by the κ-mechanism, i.e. an effect of the opacity of iron-peak elements in the envelope of the star. In the Milky Way, p-modes are observed in stars that are hotter than or equal to the B3 spectral type, while g-modes are observed at the B2 spectral type and cooler. <BR /> Aims: We observed a B0IVe star, HD 51452, with the high-precision, high-cadence photometric CoRoT satellite and high-resolution, ground-based HARPS and SOPHIE spectrographs to study its pulsations in great detail. We also used the lower resolution spectra available in the BeSS database. <BR /> Methods: We analyzed the CoRoT and spectroscopic data with several methods: Clean-NG, FreqFind, and a sliding window method. We also analyzed spectral quantities, such as the violet over red (V/R) emission variations, to obtain information about the variation in the circumstellar environment. We calculated a stellar structure model with the ESTER code to test the various interpretation of the results. <BR /> Results: We detect 189 frequencies of variations in the CoRoT light curve in the range between 0 and 4.5 c d[SUP]-1[/SUP]. The main frequencies are also recovered in the spectroscopic data. In particular we find that HD 51452 undergoes gravito-inertial modes that are not in the domain of those excited by the κ-mechanism. We propose that these are stochastic modes excited in the convective zones and that at least some of them are a multiplet of r-modes (i.e. subinertial modes mainly driven by the Coriolis acceleration). Stochastically excited gravito-inertial modes had never been observed in any star, and theory predicted that their very low amplitudes would be undetectable even with CoRoT. We suggest that the amplitudes are enhanced in HD 51452 because of the very rapid stellar rotation. In addition, we find that the amplitude variations of these modes are related to the occurrence of minor outbursts. <BR /> Conclusions: Thanks to CoRoT data, we have detected a new kind of pulsations in HD 51452, which are stochastically excited gravito-inertial modes, probably due to its very rapid rotation. These modes are probably also present in other rapidly rotating hot Be stars. The CoRoT space mission, launched on December 27, 2006, has been developed and is operated by CNES, with the contribution of Austria, Belgium, Brazil, ESA (RSSD, and Science Programs), Germany, and Spain. This work uses observations partly made with the HARPS instrument at the 3.6-m ESO telescope (La Silla, Chile) in the framework of the LP182.D-0356, as well as data obtained with Sophie at OHP and from the BeSS database.Table 3 is available in electronic form at <A href="http://www.aanda.org">http://www.aanda.org</A> [less ▲]

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See detailKepler observations of the variability in B-type stars
Balona, L. A.; Pigulski, A.; Cat, P De et al

in Monthly Notices of the Royal Astronomical Society (2011), 413

The analysis of the light curves of 48 B-type stars observed by Kepler is presented. Among these are 15 pulsating stars, all of which show low frequencies, characteristic of slowly pulsating B (SPB) stars ... [more ▼]

The analysis of the light curves of 48 B-type stars observed by Kepler is presented. Among these are 15 pulsating stars, all of which show low frequencies, characteristic of slowly pulsating B (SPB) stars. Seven of these stars also show a few weak, isolated high frequencies and they could be considered as SPB/β Cephei (β Cep) hybrids. In all cases, the frequency spectra are quite different from what is seen from ground-based observations. We suggest that this is because most of the low frequencies are modes of high degree which are predicted to be unstable in models of mid-B stars. We find that there are non-pulsating stars within the β Cep and SPB instability strips. Apart from the pulsating stars, we can identify stars with frequency groupings similar to what is seen in Be stars but which are not Be stars. The origin of the groupings is not clear, but may be related to rotation. We find periodic variations in other stars which we attribute to proximity effects in binary systems or possibly rotational modulation. We find no evidence for pulsating stars between the cool edge of the SPB and the hot edge of the δ Sct instability strips. None of the stars shows the broad features which can be attributed to stochastically excited modes as recently proposed. Among our sample of B stars are two chemically peculiar stars, one of which is a HgMn star showing rotational modulation in the light curve. [less ▲]

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See detailSkin mucus of Cyprinus carpio inhibits cyprinid herpesvirus 3 binding to epidermal cells
RAJ, Victor; Fournier, Guillaume ULg; Rakus, Krzysztof ULg et al

in Veterinary Research (2011), 42(92),

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See detailIdentification and localization of the structural proteins of anguillid herpesvirus 1
Van Beurden, Steven ULg; Leroy, B; Wattiez, R et al

in Veterinary Research (2011), 42(1), 105

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See detailThe Asteroseismic Potential of Kepler: First Results for Solar-Type Stars
Chaplin, W. J.; Appourchaux, T.; Elsworth, Y. et al

in Astrophysical Journal Letters (2010), 713

We present preliminary asteroseismic results from Kepler on three G-type stars. The observations, made at one-minute cadence during the first 33.5 days of science operations, reveal high signal-to-noise ... [more ▼]

We present preliminary asteroseismic results from Kepler on three G-type stars. The observations, made at one-minute cadence during the first 33.5 days of science operations, reveal high signal-to-noise solar-like oscillation spectra in all three stars: about 20 modes of oscillation may be clearly distinguished in each star. We discuss the appearance of the oscillation spectra, use the frequencies and frequency separations to provide first results on the radii, masses, and ages of the stars, and comment in the light of these results on prospects for inference on other solar-type stars that Kepler will observe. [less ▲]

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See detailThe genome of cyprinid herpesvirus 3 encodes 40 proteins incorporated in mature virions
Michel, Benjamin ULg; Leroy, B.; Victor, Stalinraj ULg et al

in Journal of General Virology (The) (2010)

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See detailAsteroseismology of solar-type stars with Kepler I: Data analysis
Karoff, C.; Chaplin, W. J.; Appourchaux, T. et al

in Astronomische Nachrichten (2010), 331

We report on the first asteroseismic analysis of solar-type stars observed by Kepler. Observations of three G-type stars, made at one-minute cadence during the first 33.5 days of science operations ... [more ▼]

We report on the first asteroseismic analysis of solar-type stars observed by Kepler. Observations of three G-type stars, made at one-minute cadence during the first 33.5 days of science operations, reveal high signal-to-noise solar-like oscillation spectra in all three stars: About 20 modes of oscillation can clearly be distinguished in each star. We discuss the appearance of the oscillation spectra, including the presence of a possible signature of faculae, and the presence of mixed modes in one of the three stars. [less ▲]

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See detailPhotodynamic therapy using methyl aminolevulinate in the management of primary superficial basal cell carcinoma: Clinical an health economic outcomes
Caekelbergh, K.; Nikkels, Arjen ULg; Leroy, B. et al

in Journal of Drugs in Dermatology (2009)

Background: Basal cell carcinoma (BBC) is the most common form of skin cancer worldwide. Different treatment options exist. The efficacy of photodynamic therapy with methyl aminolevulinate (MAL-PDT) has ... [more ▼]

Background: Basal cell carcinoma (BBC) is the most common form of skin cancer worldwide. Different treatment options exist. The efficacy of photodynamic therapy with methyl aminolevulinate (MAL-PDT) has been established in several randomized controlled trials (RCTs). Real life data can differ greatly from data derived from randomized controlled trials (RCTs). Objectives: To describe the results of a Belgian observational study concerning superficial BCC (sBCC) vis-à-vis clinical and health economic outcomes in order to evaluate the real-life practice of MAL-PDT. Methods: This study was a prospective, single-arm, open study conducted at eight dermatological institutions during six months after the first MAL-PDT treatment. Eligible patients had to present with lesions, suitable for MAL-PDT according to Belgian reimbursement criteria. Resource use was collected during the study period. Clinical Response (CR) and Cosmetic Outcome (CO), as well as cost of care were evaluated. A subset analysis of patients with sBCC only was conducted. Results: Ninety patients were identified for the analysis (mean age 65 years; 61 % female). The mean number of lesions per patient was 1.6, mostly located on the face, the back and the chest. For the entire period, the mean number of visits to a dermatologist was 4 per patient including two MAL-PDT sessions. The average, cumulative amount of MAL used per treatment was 1,256 mg. Two patients experienced adverse events at the application site, none of them serious, all resolved completely. The CR rate was 89 % at the end of the study. The CO was “excellent” or “good” in 96 % of the patients. Total cost of care was €289 ($ 414 U.S.) per patient. Cost per lesion was €195 ($ 280 U.S.). Conclusion: The result from the real-life practice study confirm the efficacy found in prior, prospective randomized trials. About four visits and less than one tube of MAL are needed for the full treatment of sBCC in one patient. [less ▲]

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See detailKératoses actiniques sous la loupe.
PIERARD, Gérald ULg; BASSET-SEGUIN, N.; HENGGE, U. et al

Book published by Publ. Artoos (2009)

Actinic keratoses are common lesions caused by the cumulative action of the sun’s rays on the skin of predisposed individuals. They generally develop in seniors, but they may be earlier in those who have ... [more ▼]

Actinic keratoses are common lesions caused by the cumulative action of the sun’s rays on the skin of predisposed individuals. They generally develop in seniors, but they may be earlier in those who have an occupational activity outside or who spend a lot of spare time under the sun. The depletion of the ozone layer might also be involved. [less ▲]

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See detailActinic keartosis under scrutiny: 20 questions and answers
PIERARD, Gérald ULg; BASSET-SEGUIN, N.; HENGGE, U. et al

Book published by Artoos (2009)

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See detailEmission line stars in the Milky Way with the GAIA space mission
Martayan, C.; Frémat, Y.; Blomme, R. et al

Poster (2009)

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See detailFirst asteroseismic results from CoRoT
Michel, Eric; Baglin, A.; Weiss, W. W. et al

in Communications in Asteroseismology (2008), 156

About one year after the end of the first observational run and six months after the first CoRoT data delivery, we comment the data exploitation progress for different types of stars. We consider first ... [more ▼]

About one year after the end of the first observational run and six months after the first CoRoT data delivery, we comment the data exploitation progress for different types of stars. We consider first results to illustrate how these data of unprecedented quality shed a new light on the field of stellar seismology. [less ▲]

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See detailThe Gaia satellite: a tool for Emission Line Stars and Hot Stars
Martayan, C.; Frémat, Y.; Blomme, R. et al

in SF2A-2008 (2008, November 01)

The Gaia satellite will be launched at the end of 2011. It will observe at least 1 billion stars, and among them several million emission line stars and hot stars. Gaia will provide parallaxes for each ... [more ▼]

The Gaia satellite will be launched at the end of 2011. It will observe at least 1 billion stars, and among them several million emission line stars and hot stars. Gaia will provide parallaxes for each star and spectra for stars till V magnitude equal to 17. After a general description of Gaia, we present the codes and methods, which are currently developed by our team. They will provide automatically the astrophysical parameters and spectral classification for the hot and emission line stars in the Milky Way and other close local group galaxies such as the Magellanic Clouds. [less ▲]

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