Browsing by Author "Navarro, Mario"

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    Correlation and variability of the HeI 4471 and MgII 4481 absorption lines in Be stars: A possible diagnostic tool for nonradial pulsations
    (1990) Vogt, Nikolaus; Barrera, Luis H.; Navarro, Mario
    In a total of 181 photographic spectrograms, obtained at the Manuel Foster Observatory of the Catholic University in Santiago (Chile), the equivalent widths of the absorption lines HeI 4471 and MgII 4481 have been determined for 10 selected southern Be stars and 4 normal B-type stars. The mean equivalent widths of each star are compared to published mean values from largers samples of B stars. On the average, Be stars coincide with normal B-type stars in their equivalent width. However, a striking difference between rapidly and slowly rotating stars in their line ratios (HeI/MgII) was found, which is probably an artifact due to a systematic misclassification of spectral types of rapidly rotating B stars (v sini>200 km s?1). Six of the ten Be stars show evidence for variability in HeI and/or MgII with time-scales shorter than a few days and amplitudes up to a factor 2 in equivalent width. Line variability occurs in the entire range of projected rotation velocity (70 km s?1
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    Xanthine-oxidase inhibitors and statins in chronic heart failure: Effects on vascular and functional parameters
    (ELSEVIER SCIENCE INC, 2011) Greig, Douglas; Alcaino, Hernan; Castro, Pablo F.; Garcia, Lorena; Verdejo, Hugo E.; Navarro, Mario; Lopez, Rafael; Mellado, Rosemarie; Tapia, Fabiola; Gabrielli, Luigi A.; Nogerol, Camilo; Chiong, Mario; Godoy, Ivan; Lavandero, Sergio
    BACKGROUND: Increased oxidative stress in heart failure (HF) leads to inflammation and endothelial dysfunction (ED). Both statins and allopurinol have known anti-oxidant properties, but their utility in HF has not been fully assessed.