The Mean Metal-line Absorption Spectrum of DLAs in BOSS

We study the mean absorption spectrum of the Damped Lyman alpha population at $z\sim 2.6$ by stacking normalized, rest-frame shifted spectra of $\sim 27\,000$ DLAs from the DR12 of BOSS/SDSS-III. We measure the equivalent widths of 50 individual metal absorption lines in 5 intervals of DLA hydrogen column density, 5 intervals of DLA redshift, and overall mean equivalent widths for an additional 13 absorption features from groups of strongly blended lines. The mean equivalent width of low-ionization lines increases with $N_{\rm HI}$, whereas for high-ionization lines the increase is much weaker. The mean metal line equivalent widths decrease by a factor $\sim 1.1-1.5$ from $z\sim2.1$ to $z \sim 3.5$, with small or no differences between low- and high-ionization species. We develop a theoretical model, inspired by the presence of multiple absorption components observed in high-resolution spectra, to infer mean metal column densities from the equivalent widths of partially saturated metal lines. We apply this model to 14 low-ionization species and to AlIII, SIII, SiIII, CIV, SiIV, NV and OVI. We use an approximate derivation for separating the equivalent width contributions of several lines to blended absorption features, and infer mean equivalent widths and column densities from lines of the additional species NI, ZnII, CII${}^{*}$, FeIII, and SIV. Several of these mean column densities of metal lines in DLAs are obtained for the first time; their values generally agree with measurements of individual DLAs from high-resolution, high signal-to-noise ratio spectra when they are available.Comment: Resubmitted after referee revision. Added evolution of metal-line equivalent widths with redshift (Section 5). Added assessment of result dependencies on sample and methodology. Comparison of relative abundances of DLAs vs Milky Way ISM and halo (Figure 16). Publicly available videos of composite quasar and DLA spectra realizations here: https://github.com/lluism

The cosmological bias factor of damped Lyman alpha systems: dependence on metal line strength

We measure the cosmological bias factor of damped Ly α absorbers (DLAs) from their crosscorrelation with the Ly α forest absorption, as a function of the DLA metal strength, defined from an average of equivalent widths of the strongest detectable low-ionization metal lines. A clear increase of the bias factor with metal strength is detected, as expected from a relation of metallicity and velocity dispersion with host halo mass. The relation is stronger after the metal strength is corrected for the H I column density, to make it more related to metallicity instead of metal column density. After correcting for the effects of measurement errors of the metal strength parameter, we find that the bias factor of DLAs with the weakest metal lines is close to unity, consistent with an origin in dwarf galaxies with host halo masses ∼1010M , whereas the most metal rich DLAs have a bias factor as large as bDLA ∼ 3, indicative of massive galaxies or galaxy groups in host haloes with masses ∼1012M . Our result confirms the physical origin of the relation of bias factors measured from cross-correlation studies to the host haloes of the absorbers

Origin of Metals around Galaxies. I. Catalogs of Metal-line Absorption Doublets from High-resolution Quasar Spectra

We present the first paper of the series Origin of Metals around Galaxies, which aims to explore the origin of the metals observed in the circumgalactic and intergalactic media. In this work we extract and build catalogs of metal absorbers that will be used in future analyses, and make our results publicly available to the community. We design a fully automatic algorithm to search for absorption metal-line doublets of the species C IV, N V, Si IV, and Mg II in high-resolution (R >=30,000) quasar spectra without human intervention, and apply it to the high-resolution and signal-to-noise ratio spectra of 690 quasars, observed with the UVES and HIRES instruments. We obtain 5656 C IV doublets, 7919 doublets of Mg II, 2258 of Si IV, and 239 of N V, constituting the largest high-resolution metaldoublet samples to date, and estimate the dependence of their completeness and purity on various doublet parameters such as equivalent width and redshift, using real and artificial quasar spectra. The catalogs include doublets with rest-frame line-equivalent widths down to a few mÅ, all detected at a significance above 3σ, and covering the redshifts between 1 < z =<5, properties that make them useful for a wide range of chemical evolution studies

Twice- vs. thrice-weekly moderate hypofractionated radiotherapy for prostate cancer: does overall treatment time matter?

To evaluate the influence of overall treatment time (OTT) in disease control, acute, and long-term side effects with moderate hypofractionated external beam radiotherapy (RT) for prostate cancer (PCa) delivered either twice- or thrice-a-week

The cosmological bias factor of damped Lyman alpha systems: dependence on metal line strength

We measure the cosmological bias factor of damped Ly α absorbers (DLAs) from their crosscorrelation with the Ly α forest absorption, as a function of the DLA metal strength, defined from an average of equivalent widths of the strongest detectable low-ionization metal lines. A clear increase of the bias factor with metal strength is detected, as expected from a relation of metallicity and velocity dispersion with host halo mass. The relation is stronger after the metal strength is corrected for the H I column density, to make it more related to metallicity instead of metal column density. After correcting for the effects of measurement errors of the metal strength parameter, we find that the bias factor of DLAs with the weakest metal lines is close to unity, consistent with an origin in dwarf galaxies with host halo masses ∼1010M , whereas the most metal rich DLAs have a bias factor as large as bDLA ∼ 3, indicative of massive galaxies or galaxy groups in host haloes with masses ∼1012M . Our result confirms the physical origin of the relation of bias factors measured from cross-correlation studies to the host haloes of the absorbers

The cosmological bias factor of damped Lyman alpha systems: dependence on metal line strength

We measure the cosmological bias factor of damped Ly α absorbers (DLAs) from their crosscorrelation with the Ly α forest absorption, as a function of the DLA metal strength, defined from an average of equivalent widths of the strongest detectable low-ionization metal lines. A clear increase of the bias factor with metal strength is detected, as expected from a relation of metallicity and velocity dispersion with host halo mass. The relation is stronger after the metal strength is corrected for the H I column density, to make it more related to metallicity instead of metal column density. After correcting for the effects of measurement errors of the metal strength parameter, we find that the bias factor of DLAs with the weakest metal lines is close to unity, consistent with an origin in dwarf galaxies with host halo masses ∼1010M , whereas the most metal rich DLAs have a bias factor as large as bDLA ∼ 3, indicative of massive galaxies or galaxy groups in host haloes with masses ∼1012M . Our result confirms the physical origin of the relation of bias factors measured from cross-correlation studies to the host haloes of the absorbers

TSH Levels as an Independent Risk Factor for NAFLD and Liver Fibrosis in the General Population

Thyroid hormones may be a risk factor for the development of non-alcoholic fatty liver disease (NAFLD) and its progression to liver fibrosis. The aim of this study is to investigate the relationship between thyroid stimulating hormone (TSH) levels, NAFLD, and liver fibrosis in the general population. A descriptive cross-sectional study was performed in subjects aged 18-75 years randomly selected from primary care centers between 2012 and 2016. Each subject underwent clinical evaluation, physical examination, blood tests and transient elastography. Descriptive and multivariate logistic regression analyses were used to identify factors associated with NAFLD and fibrosis. We included 2452 subjects (54 ± 12 years; 61% female). Subjects with TSH ≥ 2.5 μIU/mL were significantly associated with obesity, atherogenic dyslipidemia, metabolic syndrome (MetS), hypertransaminasemia and altered cholesterol and triglycerides. The prevalence of NAFLD and liver fibrosis was significantly higher in subjects with TSH ≥ 2.5 (μIU/mL). We found a 1.5 times increased risk of NAFLD, 1.8 and 2.3 times increased risk of liver fibrosis for cut-off points of ≥8.0 kPa and ≥9.2 kPa, respectively, in subjects with TSH ≥ 2.5 μIU/mL compared with TSH < 2.5 μIU/mL (control group), independent of the presence of MetS. These findings remained significant when stratifying TSH, with values ≥ 10 μIU/mL

Programmable Organic Chipless RFID Tags Inkjet Printed on Paper Substrates

Altres ajuts: Agència per a la Competitivitat de l'Empresa de la Generalitat de Catalunya by FEDER funds, Institució Catalana de Recerca i Estudis Avançats, and ERDF fundsIn this paper, an organic, fully recyclable and eco-friendly 20-bit inkjet-printed chipless RFID tag is presented. The tag operates in the near field and is implemented by means of chains of resonant elements. The characterization and manufacturing process of the tag, printed with a few layers of a commercial organic ink on conventional paper substrate (DIN A4), are presented, and tag functionality is demonstrated by reading it by means of a custom-designed reader. The tags are read by proximity (through the near field), by displacing them over a resonator-loaded transmission line, and each resonant element (bit) of the tag is interrogated by a harmonic signal tuned to the resonance frequency. The coupling between the reader line and the resonant elements of the tag produce and amplitude modulated (AM) signal containing the identification (ID) code of the tag

Origin of Metals around Galaxies. I. Catalogs of Metal-line Absorption Doublets from High-resolution Quasar Spectra

We present the first paper of the series Origin of Metals around Galaxies, which aims to explore the origin of the metals observed in the circumgalactic and intergalactic media. In this work we extract and build catalogs of metal absorbers that will be used in future analyses, and make our results publicly available to the community. We design a fully automatic algorithm to search for absorption metal-line doublets of the species C IV, N V, Si IV, and Mg II in high-resolution (R >=30,000) quasar spectra without human intervention, and apply it to the high-resolution and signal-to-noise ratio spectra of 690 quasars, observed with the UVES and HIRES instruments. We obtain 5656 C IV doublets, 7919 doublets of Mg II, 2258 of Si IV, and 239 of N V, constituting the largest high-resolution metaldoublet samples to date, and estimate the dependence of their completeness and purity on various doublet parameters such as equivalent width and redshift, using real and artificial quasar spectra. The catalogs include doublets with rest-frame line-equivalent widths down to a few mÅ, all detected at a significance above 3σ, and covering the redshifts between 1 < z =<5, properties that make them useful for a wide range of chemical evolution studies