References of "Garcia, R"
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See detailKepler Detected Gravity-Mode Period Spacings in a Red Giant Star
Beck, P. G.; Bedding, T. R.; Mosser, B. et al

in Science (2011), 332

Stellar interiors are inaccessible through direct observations. For this reason, helioseismologists made use of the Sun’s acoustic oscillation modes to tune models of its structure. The quest to detect ... [more ▼]

Stellar interiors are inaccessible through direct observations. For this reason, helioseismologists made use of the Sun’s acoustic oscillation modes to tune models of its structure. The quest to detect modes that probe the solar core has been ongoing for decades. We report the detection of mixed modes penetrating all the way to the core of an evolved star from 320 days of observations with the Kepler satellite. The period spacings of these mixed modes are directly dependent on the density gradient between the core region and the convective envelope. [less ▲]

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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 detailKepler observations: Light shed on the hybrid γ Doradus - δ Scuti pulsation phenomenon
Grigahcène, A.; Uytterhoeven, K.; Antoci, V. et al

in Astronomische Nachrichten (2010), 331

Through the observational study of stellar pulsations, the internal structure of stars can be probed and theoretical models can be tested. The main sequence γ Doradus (Dor) and δ Scuti (Sct) stars with ... [more ▼]

Through the observational study of stellar pulsations, the internal structure of stars can be probed and theoretical models can be tested. The main sequence γ Doradus (Dor) and δ Scuti (Sct) stars with masses 1.2-2.5 M[SUB]ȯ[/SUB] are particularly interesting for asteroseismic study. The γ Dor stars pulsate in high-order gravity (g) modes, with pulsational periods of order of one day. The δ Sct stars, on the other hand, show low-order g and pressure (p) modes with periods of order of 2 hours. Theory predicts the existence of `hybrid' stars, i.e. stars pulsating in both types of modes, in an overlap region between the instability strips of γ Dor and δ Sct stars in the Hertzsprung-Russell diagram. Hybrid stars are particularly interesting as the two types of modes probe different regions of the stellar interior and hence provide complementary model constraints. Before the advent of Kepler, only a few hybrid stars had been confirmed. The {{Kepler}} satellite is providing a true revolution in the study of and search for hybrid stars. Analysis of the first 50 days of {{Kepler}} data of hundreds of γ Dor and δ Sct candidates reveals extremely rich frequency spectra, with most stars showing frequencies in both the δ Sct and γ Dor frequency range. As these results show that there are practically no pure δ Sct or γ Dor pulsators, a new observational classification scheme is proposed by \cite{Grig10}. We present their results and characterize 234 stars in terms of δ Sct, γ Dor, δ Sct/γ Dor or γ Dor/δ Sct hybrids. [less ▲]

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See detailSkin in maturity: the endocrine and neuroendocrine pathways.
Quatresooz, Pascale ULg; Pierard, Claudine ULg; Kharfi, Monia et al

in International Journal of Cosmetic Science (2007), 29(1), 1-6

Irrespective of age, most of the skin components are under the physiological control of endocrine and neuroendocrine factors. There is evidence that skin ageing appears complex showing much ... [more ▼]

Irrespective of age, most of the skin components are under the physiological control of endocrine and neuroendocrine factors. There is evidence that skin ageing appears complex showing much interindividual variability. Conceptually, ageing is a single biological process that is influenced and modulated by a series of various internal and exogenous factors. Among them, hormones and neuroendocrine signals play key roles in several ways. Ageing of most endocrine glands will in turn alter the skin biology. In addition, the age-related reduction in the intrinsic neuroendocrine activity of the skin will also alter the ageing rate of this organ. At last, various endocrinopathies will boost or conversely decrease the severity of the signs of cutaneous ageing. [less ▲]

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See detailA dynamic upper atmosphere of Venus as revealed by VIRTIS on Venus Express
Drossart, P.; Piccioni, G.; Gérard, Jean-Claude ULg et al

in Nature (2007), 450

The upper atmosphere of a planet is a transition region in which energy is transferred between the deeper atmosphere and outer space. Molecular emissions from the upper atmosphere (90-120 km altitude) of ... [more ▼]

The upper atmosphere of a planet is a transition region in which energy is transferred between the deeper atmosphere and outer space. Molecular emissions from the upper atmosphere (90-120 km altitude) of Venus can be used to investigate the energetics and to trace the circulation of this hitherto little-studied region. Previous spacecraft(1) and ground-based(2-4) observations of infrared emission from CO2, O-2 and NO have established that photochemical and dynamic activity controls the structure of the upper atmosphere of Venus. These data, however, have left unresolved the precise altitude of the emission(1) owing to a lack of data and of an adequate observing geometry(5,6). Here we report measurements of day-side CO2 non-local thermodynamic equilibrium emission at 4.3 mu m, extending from 90 to 120 km altitude, and of night-side O-2 emission extending from 95 to 100 km. The CO2 emission peak occurs at similar to 115 km and varies with solar zenith angle over a range of similar to 10 km. This confirms previous modelling(7), and permits the beginning of a systematic study of the variability of the emission. The O-2 peak emission happens at 96 km +/- 1 km, which is consistent with three-body recombination of oxygen atoms transported from the day side by a global thermospheric sub-solar to anti-solar circulation, as previously predicted(8). [less ▲]

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See detailPitted keratolysis: new ultrastructural insight in keratohyalin granule and corneodesmosome alterations.
Hermanns-Lê, Trinh ULg; Garcia, R.; Arrese Estrada, Jean-Marie ULg et al

in Exogenous Dermatology : Physical, Chemical, Biological (2004), 3

Background: Pitted keratolysis (PK) is a superficial cutaneous infection caused by different species of bacteria. It is characterized by discrete crateriform and malodorous pits and erosions coalescing to ... [more ▼]

Background: Pitted keratolysis (PK) is a superficial cutaneous infection caused by different species of bacteria. It is characterized by discrete crateriform and malodorous pits and erosions coalescing to form bizarre figures on the soles. Objective: To investigate the process of corneocyte shedding in PK. Method: Biopsies from typical lesions of three patients were investigated by transmission electron microscopy. Results: Microorganisms were found both inter- and intracellularly in corneocytes and keratinocytes of the upper layers of the stratum spinosum. Bacteria exhibited different morphologic aspects related to their localisation in the epidermis. Keratohyalin granules were strikingly abnormal, showing sharp segregation between rounded dense areas and more electron-translucent areas. Some keratohyalin granules exhibited only alveolar dense areas. These altered keratohyalin granules were still present inside corneocytes. The corneodesmosomes at the bottom of the pits were in part cleaved leading to partial corneocyte dissociation. Conclusion: It is suggested that proteases secreted by the bacteria alter the structure of both the corneodesmosomes and the keratohyalin granules. The latter appeared more resistant to the normal processing of profilaggrin inside the corneocytes. [less ▲]

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See detailPrévention de la fibrillation auriculaire récidivante et resynchronisation bi-atriale
Evrard, P.; Sakalihasan, Natzi ULg; Garcia, R. et al

in Revue Médicale de Liège (1999), 54(6), 522-6

After conversion of atrial fibrillation, it is important to maintain sinus rhythm. In addition antiarrhythmic drugs, biatrial resynchronization seems to prevent recurrences of atrial fibrillation in ... [more ▼]

After conversion of atrial fibrillation, it is important to maintain sinus rhythm. In addition antiarrhythmic drugs, biatrial resynchronization seems to prevent recurrences of atrial fibrillation in patients with interatrial conduction block: local experience. [less ▲]

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