Stellar Population gradients in galaxy discs from the CALIFA survey

While studies of gas-phase metallicity gradients in disc galaxies are common, very little has been done in the acquisition of stellar abundance gradients in the same regions. We present here a comparative study of the stellar metallicity and age distributions in a sample of 62 nearly face-on, spiral galaxies with and without bars, using data from the CALIFA survey. We measure the slopes of the gradients and study their relation with other properties of the galaxies. We find that the mean stellar age and metallicity gradients in the disc are shallow and negative. Furthermore, when normalized to the effective radius of the disc, the slope of the stellar population gradients does not correlate with the mass or with the morphological type of the galaxies. Contrary to this, the values of both age and metallicity at $\sim$2.5 scale-lengths correlate with the central velocity dispersion in a similar manner to the central values of the bulges, although bulges show, on average, older ages and higher metallicities than the discs. One of the goals of the present paper is to test the theoretical prediction that non-linear coupling between the bar and the spiral arms is an efficient mechanism for producing radial migrations across significant distances within discs. The process of radial migration should flatten the stellar metallicity gradient with time and, therefore, we would expect flatter stellar metallicity gradients in barred galaxies. However, we do not find any difference in the metallicity or age gradients in galaxies with without bars. We discuss possible scenarios that can lead to this absence of difference.Comment: 24 pages, 17 figures, accepted for publication in A&

Atmospheric pressure gas chromatography-time-of-flight-mass spectrometry (APGC-ToF-MS) for the determination of regulated and emerging contaminants in aqueous samples after stir bar sorptive extraction (SBSE)

This work presents the development, optimization and validation of a multi-residue method for the simultaneous determination of 102 contaminants, including fragrances, UV filters, repellents, endocrine disruptors, biocides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and several types of pesticides in aqueous matrices. Water samples were processed using stir bar sorptive extraction (SBSE) after the optimization of several parameters: agitation time, ionic strength, presence of organic modifiers, pH, and volume of the derivatizing agent. Target compounds were extracted from the bars by liquid desorption (LD). Separation, identification and quantification of analytes were carried out by gas chromatography (GC) coupled to time-of-flight (ToF-MS) mass spectrometry. A new ionization source, atmospheric pressure gas chromatography (APGC), was tested. The optimized protocol showed acceptable recovery percentages (50–100%) and limits of detection below 1 ng L−1 for most of the compounds. Occurrence of 21 out of 102 analytes was confirmed in several environmental aquatic matrices, including seawater, sewage effluent, river water and groundwater. Non-target compounds such as organophosphorus flame retardants were also identified in real samples by accurate mass measurement of their molecular ions using GC-APGC–ToF-MS. To the best of our knowledge, this is the first time that this technique has been applied for the analysis of contaminants in aquatic systems. By employing lower energy than the more widely used electron impact ionization (EI), AGPC provides significant advantages over EI for those substances very susceptible to high fragmentation (e.g., fragrances, pyrethroids)

Diagnostic Accuracy of Anthropometric Markers of Obesity for Prediabetes: A Systematic Review and Meta-Analysis

Introduction: Prediabetes is a significant public health concern due to its high risk of progressing to diabetes. Anthropometric measures of obesity, including body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) have been demonstrated as key risk factors in the development of prediabetes. However, there is a lack of clarity on the diagnostic accuracy and cut-off points of these measures. Objective: To determine the diagnostic accuracy of these anthropometric measures for their most effective use in identifying prediabetes. Methodology: A systematic review (SR) with metanalysis of observational studies was carried out. The search was conducted in four databases: Pubmed/Medline, SCOPUS, Web of Science, and EMBASE. For the meta-analysis, sensitivity and specificity, together with their 95% confidence intervals (CI 95%) were calculated. Results: Among all the manuscripts chosen for review, we had four cross-sectional studies, and three were classified as cohort studies. The forest plots showed the combined sensitivity and specificity for both cross-sectional and cohort studies. For cross-sectional studies, the values were as follows: BMI had a sensitivity of 0.63 and specificity of 0.56, WC had a sensitivity of 0.59 and specificity of 0.58, and WHtR had a sensitivity of 0.63 and specificity of 0.73. In the cohort studies, the combined sensitivity and specificity were: BMI at 0.70 and 0.45, WC at 0.68 and 0.56, and WHtR at 0.68 and 0.56, respectively. All values are provided with 95% confidence intervals. Conclusions: This systematic review and meta-analysis evaluated the diagnostic accuracy of BMI, WC, and WHtR in identifying prediabetes. The results showed variations in sensitivity and specificity, with WHtR having the highest specificity in cross-sectional studies and BMI having improved sensitivity in cohort studies

The Mass-Metallicity relation explored with CALIFA: I. Is there a dependence on the star formation rate?

We present the results on the study of the global and local M-Z relation based on the first data available from the CALIFA survey (150 galaxies). This survey provides integral field spectroscopy of the complete optical extent of each galaxy (up to 2-3 effective radii), with enough resolution to separate individual HII regions and/or aggregations. Nearly $\sim$3000 individual HII regions have been detected. The spectra cover the wavelength range between [OII]3727 and [SII]6731, with a sufficient signal-to-noise to derive the oxygen abundance and star-formation rate associated with each region. In addition, we have computed the integrated and spatially resolved stellar masses (and surface densities), based on SDSS photometric data. We explore the relations between the stellar mass, oxygen abundance and star-formation rate using this dataset. We derive a tight relation between the integrated stellar mass and the gas-phase abundance, with a dispersion smaller than the one already reported in the literature ($\sigma_{\Delta{\rm log(O/H)}}=$0.07 dex). Indeed, this dispersion is only slightly larger than the typical error derived for our oxygen abundances. However, we do not find any secondary relation with the star-formation rate, other than the one induced due to the primary relation of this quantity with the stellar mass. We confirm the result using the $\sim$3000 individual HII regions, for the corresponding local relations. Our results agree with the scenario in which gas recycling in galaxies, both locally and globally, is much faster than other typical timescales, like that of gas accretion by inflow and/or metal loss due to outflows. In essence, late-type/disk dominated galaxies seem to be in a quasi-steady situation, with a behavior similar to the one expected from an instantaneous recycling/closed-box model.Comment: 19 Pages, 8 figures, Accepted for Publishing in Astronomy and Astrophysics (A&A

Newborns of Mothers with Venous Disease during Pregnancy Show Increased Levels of Lipid Peroxidation and Markers of Oxidative Stress and Hypoxia in the Umbilical Cord

The study (FIS-PI18/00912) was supported by the Instituto de Salud Carlos III (grant no. Estatal de I + D + I 2013–2016) and co-financed by the European Development Regional Fund “A way to achieve Europe” and B2017/BMD-3804 MITIC-CM (Comunidad de Madrid), and Halekulani S.L.Chronic venous disease (CVD) encompasses a set of disorders of the venous system that have a high prevalence in Western societies and are associated with significant sociohealth costs. Pregnancy is a period in which different hormonal and haemodynamic changes occur that lead to significant changes in the cardiovascular system, increasing the risk of developing venous problems, especially during the third trimester of gestation. In turn, CVD involves a series of local and systemic alterations that can have negative repercussions in pregnancy. In this context, the role of oxidative stress in the pathophysiology of this condition has been shown to significantly affect other vascular structures during pregnancy, such as the placenta. However, the effects of oxidative stress on the umbilical cord in women with CVD have not yet been fully elucidated. Thus, the objective of this study was to analyse the gene and protein expression of the enzymes NOX-1, NOX-2 and iNOS, which are involved in the production of reactive oxygen and nitrogen species, respectively. Similarly, the presence of hypoxia-inducible factor 1-alpha (HIF-1α) in the umbilical cord in women with CVD was compared to that of pregnant control women, and the levels of the lipid peroxidation marker malonyldialdehyde (MDA) in cord tissue and blood was also analysed. Our results support a significant increase in the enzymes NOX-1, NOX-2 and iNOS and HIF-1α and MDA in the umbilical cord tissue and blood of women with CVD. For the first time, our work demonstrates an increase in oxidative stress and cellular damage in the umbilical cords of pregnant women who develop this condition, deepening the understanding of the consequences of CVD during pregnancy.Depto. de Salud Pública y Materno - InfantilFac. de MedicinaTRUEUnión EuropeaComunidad de MadridInstituto de Salud Carlos IIIHalekulanipu

Peces de la subcuenca del río Catatumbo, cuenca del Lago de Maracaibo, Colombia y Venezuela

Records from the literature supplemented by reviewing reference collection specimens of fish in the Humboldt Institute - IAvH-P, Rancho Grande Biological Station - EBRG and Museum of Natural Sciences Guanare -MCNG, show 109 freshwater native species and 14 of marine estuarine origin living in the Catatumbo river basin, making it the system with the highest diversity of fish species on Maracaibo Lake. These species belong to 10 orders, 39 families and 91 genera. The taxonomic orders with the highest number of families, genera and species were Siluriformes with 12 families, 42 genera and 61 species and Characiformes with 11 families, 24 genera and 32 species. The richest families were Loricariidae (16 genera and 25 species), Characidae (13 genera and 18 species) and Pimelodidae (6 genera and 8 species), there were between one and five species recorded in each of the remaining 37 families. Of the 123 species registered, 69 were collected and cataloged as sampling results of this study and 11 are new registers for Colombia. As for the Catatumbo 61 of the 68 species are considered endemic to the Maracaibo Lake basin and 40 were established themselves as commonly fished species for commercial purposes, six marine - estuarine and 34 freshwater. This paper discusses changes in the number of species registered in the different lists and their implications for species richness Catatumbo basin

Peces de la subcuenca del río Catatumbo, cuenca del Lago de Maracaibo, Colombia y Venezuela

Records from the literature supplemented by reviewing reference collection specimens of fish in the Humboldt Institute - IAvH-P, Rancho Grande Biological Station - EBRG and Museum of Natural Sciences Guanare -MCNG, show 109 freshwater native species and 14 of marine estuarine origin living in the Catatumbo river basin, making it the system with the highest diversity of fish species on Maracaibo Lake. These species belong to 10 orders, 39 families and 91 genera. The taxonomic orders with the highest number of families, genera and species were Siluriformes with 12 families, 42 genera and 61 species and Characiformes with 11 families, 24 genera and 32 species. The richest families were Loricariidae (16 genera and 25 species), Characidae (13 genera and 18 species) and Pimelodidae (6 genera and 8 species), there were between one and five species recorded in each of the remaining 37 families. Of the 123 species registered, 69 were collected and cataloged as sampling results of this study and 11 are new registers for Colombia. As for the Catatumbo 61 of the 68 species are considered endemic to the Maracaibo Lake basin and 40 were established themselves as commonly fished species for commercial purposes, six marine - estuarine and 34 freshwater. This paper discusses changes in the number of species registered in the different lists and their implications for species richness Catatumbo basin.Registros de literatura, complementados con la revisión de ejemplares de colección de referencia de peces del Instituto Humboldt - IAvH-P (Colombia), Estación Biológica de Rancho Grande - EBRG y Museo de Ciencias Naturales de Guanare - MCNG (Venezuela), muestran que 109 especies nativas de agua dulce y 14 de origen marino y estuarino habitan la subcuenca el río Catatumbo, constituyéndose en el sistema con mayor diversidad de especies de peces de la cuenca del Lago de Maracaibo. Estas especies pertenecen a 10 órdenes, 39 familias y 91 géneros. Los órdenes con mayor número de familias, géneros y especies fueron Siluriformes con 12 familias, 42 géneros y 60 especies, y Characiformes 11 familias, 24 géneros y 32 especies. Las familias con mayor riqueza fueron Loricariidae (16 géneros y 25 especies), Characidae (13 géneros y 18 especies) y Pimelodidae (6 géneros y 8 especies); presentando las restantes 37 familias entre una y cinco especies. De las 123 especies registradas, 69 fueron capturadas y catalogadas como resultados de los muestreos durante el presente estudio y 11 corresponden a nuevos registros para Colombia. Para el río Catatumbo se registraron 61 especies de las 68 consideradas endémicas para la cuenca del Lago de Maracaibo y se establecieron como especies pesqueras 40, de las cuales seis fueron marino-estuarinas y 34 dulceacuícolas. Se discute las variaciones del número de especies registradas en los diferentes listados y sus implicaciones en la riqueza de especies para la subcuenca del Catatumbo

CALIFA, the Calar Alto Legacy Integral Field Area survey: I. Survey presentation

We present here the Calar Alto Legacy Integral Field Area (CALIFA) survey, which has been designed to provide a first step in this direction.We summarize the survey goals and design, including sample selection and observational strategy.We also showcase the data taken during the first observing runs (June/July 2010) and outline the reduction pipeline, quality control schemes and general characteristics of the reduced data. This survey is obtaining spatially resolved spectroscopic information of a diameter selected sample of $\sim600$ galaxies in the Local Universe (0.005< z <0.03). CALIFA has been designed to allow the building of two-dimensional maps of the following quantities: (a) stellar populations: ages and metallicities; (b) ionized gas: distribution, excitation mechanism and chemical abundances; and (c) kinematic properties: both from stellar and ionized gas components. CALIFA uses the PPAK Integral Field Unit (IFU), with a hexagonal field-of-view of \sim1.3\sq\arcmin', with a 100% covering factor by adopting a three-pointing dithering scheme. The optical wavelength range is covered from 3700 to 7000 {\AA}, using two overlapping setups (V500 and V1200), with different resolutions: R\sim850 and R\sim1650, respectively. CALIFA is a legacy survey, intended for the community. The reduced data will be released, once the quality has been guaranteed. The analyzed data fulfill the expectations of the original observing proposal, on the basis of a set of quality checks and exploratory analysis. We conclude from this first look at the data that CALIFA will be an important resource for archaeological studies of galaxies in the Local Universe.Comment: 32 pages, 29 figures, Accepted for publishing in Astronomy and Astrophysic

Eliminating Error in the Chemical Abundance Scale for Extragalactic HII Regions

In an attempt to remove the systematic errors which have plagued the calibration of the HII region abundance sequence, we have theoretically modeled the extragalactic HII region sequence. We then used the theoretical spectra so generated in a double blind experiment to recover the chemical abundances using both the classical electron temperature + ionization correction factor technique, and the technique which depends on the use of strong emission lines (SELs) in the nebular spectrum to estimate the abundance of oxygen. We find a number of systematic trends, and we provide correction formulae which should remove systematic errors in the electron temperature + ionization correction factor technique. We also provide a critical evaluation of the various semi-empirical SEL techniques. Finally, we offer a scheme which should help to eliminate systematic errors in the SEL-derived chemical abundance scale for extragalactic HII regions.Comment: 24 pages, 9 Tables, 13 figures, accepted for publication in MNRAS. Updated considering minor changes during the final edition process and some few missing reference

Stress-Softening and Residual Strain Effects in Suture Materials

This work focuses on the experimental characterization of suture material samples of MonoPlus, Monosyn, polyglycolic acid, polydioxanone 2–0, polydioxanone 4–0, poly(glycolide-co-epsilon-caprolactone), nylon, and polypropylene when subjected to cyclic loading and unloading conditions. It is found that all tested suture materials exhibit stress-softening and residual strain effects related to the microstructural material damage upon deformation from the natural, undistorted state of the virgin suture material. To predict experimental observations, a new constitutive material model that takes into account stress-softening and residual strain effects is developed. The basis of this model is the inclusion of a phenomenological nonmonotonous softening function that depends on the strain intensity between loading and unloading cycles. The theory is illustrated by modifying the non-Gaussian average-stretch, full-network model to capture stress-softening and residual strains by using pseudoelasticity concepts. It is shown that results obtained from theoretical simulations compare well with suture material experimental data