Selection of the solvent and extraction conditions for maximum recovery of antioxidant phenolic compounds from coffee silverskin

The extraction of antioxidant phenolic compounds from coffee silverskin (CS) was studied. Firstly, the effect of different solvents (methanol, ethanol, acetone, and distilled water) on the production of antioxidant extracts was evaluated. All the extracts showed antioxidant activity (FRAP and DPPH assays), but those obtained with methanol and ethanol had significantly higher (p < 0.05) DPPH inhibition than the remaining ones. Due to the lower toxicity, ethanol was selected as extraction solvent, and further experiments were performed in order to define the solvent concentration, solvent/solid ratio, and time to maximize the extraction results. The best condition to produce an extract with high content of phenolic compounds (13 mg gallic acid equivalents/g CS) and antioxidant activity [DPPH = 18.24 μmol Trolox equivalents/g CS and FRAP = 0.83 mmol Fe(II)/g CS] was achieved when using 60 % ethanol in a ratio of 35 ml/g CS, during 30 min at 60–65 °C.This work was supported by the Portuguese Foundation for Science and Technology (FCT). The authors gratefully acknowledge Teresa Conde, student of Biological Engineering, for the help and interest in this work

Rest-frame UV Properties of Luminous Strong Gravitationally Lensed Lyα\alpha Emitters from the BELLS GALLERY Survey

We present deep rest-frame UV spectroscopic observations using the Gran Telescopio Canarias of six gravitationally lensed Lya emitters (LAEs) at $2.36<z<2.82$ selected from the BELLS GALLERY survey. By taking the magnifications into account, we show that LAEs can be as luminous as L(Lya) = 30x10$^{42}$ erg s-1 and M(UV) = -23 (AB) without invoking an AGN component, in contrast with previous findings. We measure Lya rest-frame equivalent widths, EW(Lya), ranging from 16\AA to 50\AA and Lya escape fractions, fesc(Lya), from 10% to 40%. Large EW(Lya) and fesc(Lya) are found predominantly in LAEs showing weak low-ionization ISM absorption (EW < 1\AA) and narrow Lya profiles (< 300 km s-1 FWHM) with their peak close (< 80 km s-1) to their systemic redshifts, suggestive of less scatter from low HI column densities that favours the escape of Lya photons. We infer stellar metallicities of Z/Zsun ~ 0.2 in almost all LAEs by comparing the P-Cygni profiles of the wind lines NV1240\AA and CIV1549\AA with those from stellar synthesis models. We also find a trend between M(UV) and the velocity offset of ISM absorption lines, such as the most luminous LAEs experience stronger outflows. The most luminous LAEs show star formation rates up to 180 Msun yr-1, yet they appear relatively blue ($\beta$(UV) ~ -1.8 to -2.0) showing evidence of little dust attenuation (E(B-V) = 0.10-0.14). These luminous LAEs may be particular cases of young starburst galaxies that have had no time to form large amounts of dust. If so, they are ideal laboratories to study the early phase of massive star formation, stellar and dust mass growth, and chemical enrichment histories of starburst galaxies at high-z.Comment: 23 pages, 10 figures, 6 tables. Accepted for publication in MNRA

Assessing the photometric redshift precision of the S-PLUS survey: The Stripe-82 as a test-case

Indexación ScopusIn this paper we present a thorough discussion about the photometric redshift (photo-z) performance of the Southern Photometric Local Universe Survey (S-PLUS). This survey combines a seven narrow +5 broad passband filter system, with a typical photometric-depth of r ∼ 21 AB. For this exercise, we utilize the Data Release 1 (DR1), corresponding to 336 deg2 from the Stripe-82 region. We rely on the BPZ2 code to compute our estimates, using a new library of SED models, which includes additional templates for quiescent galaxies. When compared to a spectroscopic redshift control sample of ∼100 k galaxies, we find a precision of σz <0.8 per cent, <2.0 per cent, or <3.0 per cent for galaxies with magnitudes r < 17, <19, and <21, respectively. A precision of 0.6 per cent is attained for galaxies with the highest Odds values. These estimates have a negligible bias and a fraction of catastrophic outliers inferior to 1 per cent. We identify a redshift window (i.e. 0.26 < z < 0.32) where our estimates double their precision, due to the simultaneous detection of two emission lines in two distinct narrow bands; representing a window opportunity to conduct statistical studies such as luminosity functions. We forecast a total of ∼2 M, ∼16 M and ∼32 M galaxies in the S-PLUS survey with a photo-z precision of σz <1.0 per cent, <2.0 per cent, and <2.5 per cent after observing 8000 deg2. We also derive redshift probability density functions, proving their reliability encoding redshift uncertainties and their potential recovering the n(z) of galaxies at z < 0.4, with an unprecedented precision for a photometric survey in the Southern hemisphere. © 2020 The Author(s)https://academic-oup-com.recursosbiblioteca.unab.cl/mnras/article/499/3/3884/585601

Papel de la enfermería en las unidades de cuidados intensivos cardiológicos para predecir la estancia media hospitalaria mediante el índice de Barthel en pacientes con síndrome coronario agudo

1.240 JCR (2013) Q4, 24/27 Critical care medicineUE

Papel de la enfermería en las unidades de cuidados intensivos cardiológicos para predecir la estancia media hospitalaria mediante el índice de Barthel en pacientes con síndrome coronario agudo

1.240 JCR (2013) Q4, 24/27 Critical care medicineUE

Rest-frame UV properties of luminous strong gravitationally lensed Ly¿ emitters from the BELLS GALLERY Survey

We present deep rest-frame UV spectroscopic observations using the Gran Telescopio Canarias of six gravitationally lensed Ly¿ emitters (LAEs) at 2.36 < z < 2.82 selected from the BELLS GALLERY survey. By taking the magnifications into account, we show that LAEs can be as luminous as LLy¿ ¿ 30 × 1042 erg s-1 and MUV ¿ -23 (AB) without invoking an AGN component, in contrast with previous findings. We measure Ly¿ rest-frame equivalent widths, EW0 (Ly¿), ranging from 16 to 50 Å and Ly¿ escape fractions, f_esc (Ly¿), from 10 per cent to 40 per cent. Large EW0 (Ly¿) and f_esc (Ly¿) are found predominantly in LAEs showing weak low-ionization ISM absorption (EW0 ¿ 1 Å) and narrow Ly¿ profiles (¿300 km s-1 FWHM) with their peak close (¿80 km s-1) to their systemic redshifts, suggestive of less scatter from low H I column densities that favours the escape of Ly¿ photons. We infer stellar metallicities of Z/Z¿ ¿ 0.2 in almost all LAEs by comparing the P-Cygni profiles of the wind lines N V1240 Å and C IV1549 Å with those from stellar synthesis models. We also find a trend between MUV and the velocity offset of ISM absorption lines, such as the most luminous LAEs experience stronger outflows. The most luminous LAEs show star formation rates up to ¿180 M¿ yr-1, yet they appear relatively blue (ßUV ¿ -1.8 to -2.0) showing evidence of little dust attenuation [E(B - V) = 0.10-0.14]. These luminous LAEs may be particular cases of young starburst galaxies that have had no time to form large amounts of dust. If so, they are ideal laboratories to study the early phase of massive star formation, stellar and dust mass growth, and chemical enrichment histories of starburst galaxies at high-z.With funding from the Spanish government through the "María de Maeztu Unit of Excellence" accreditation (MDM-2017-0737