Marine 5-thiohistidines as protective molecules from skin damage

Introduction Marine environment is a great source of bioactive molecules, whose biological properties and applications are often used especially to prevent skin diseases and aging caused by UVA­exposure. Ovothiols are methyl­5­thiohistidines from marine invertebrates, bacteria, and microalgae, which protect cells from environmental stressors. Recently, we have shown that, ovothiol, isolated from sea urchin eggs, exerts anti­inflammatory and antioxidant activities on human endothelial cells, and exhibits antifibrotic effect in an in vivo model of liver fibrosis.info:eu-repo/semantics/publishedVersio

Examining the relationship between sugar content, packaging features, and food claims of breakfast cereals

Excessive free-sugar intake has become highly prevalent in numerous countries, and Portugal is not the exception. One product category that contributes to the daily intake of free sugars is breakfast cereals. In the current work, we identified 289 exemplars from two major retailers in Portugal and collected information on their nutritional profile (e.g., sugar, salt, fiber per 100 g), price, packaging features, type of food claims present (e.g., statements about the composition, sensory features, the origin of the product), and ingredients list. Overall, the sugar content of breakfast cereals was high (Mean = 19.9 g), and less than 10% of the products complied with the current national guidelines (i.e., 5 g of sugar per 100 g of product). Sugar (or other sugar sources) was listed in the top three ingredients for over 85% of the products. On average, each product included about four claims (Mean = 3.9), and sugar content was lower when the claims were related to the product composition. Critically, the sugar content was particularly high for children-oriented products (Mean = 26.4 g). Correlation analysis showed that breakfast cereals with higher sugar content also were cheaper and had lower quantities of fiber, proteins, and salt. Our findings suggest the need to implement strategies to reduce sugar in this product category (e.g., incentivize manufacturers to reformulate products). Also, our results may inform strategies aimed at promoting consumers’ awareness about the sugar content in breakfast cereals and other processed foods, facilitating healthier decision-making.info:eu-repo/semantics/publishedVersio

Evidence for a Physically Compact Narrow-Line Region in the Seyfert 1 Galaxy NGC 5548

We have combined HST/FOS and ground-based spectra of the Seyfert 1 galaxy NGC 5548 to study the narrow emission lines over the 1200 -- 10,000 angstrom region. All of the spectra were obtained when the broad emission line and continuum fluxes were at an historic low level, allowing us to accurately determine the contribution of the narrow-line region (NLR) to the emission lines. We have generated multicomponent photoionization models to investigate the relative strength of the high ionization lines compared to those in Seyfert 2 galaxies, and the weakness of the narrow Mg II 2800 line. We present evidence for a high ionization component of NLR gas that is very close to the nucleus (~1 pc). This component must be optically thin to ionizing radiation at the Lyman edge (tau = 2.5) to avoid producing [O I] and Mg II in a partially ionized zone. The very high ionization lines (N V, [Ne V], [Fe VII], [Fe X]) are stronger than the predictions of our standard model, and we show that this may be due to supersolar abundances and/or a ``blue bump'' in the extreme ultraviolet (although recent observations do not support the latter). An outer component of NLR gas (at only ~70 pc from the continuum source) is needed to produce the low ionization lines. We show that the outer component may contain dust, which further reduces the Mg II flux by depletion and by absorption of the resonance photons after multiple scatterings. We show that the majority of the emission in the NLR of NGC 5548 must arise within about ~70 pc from the nucleus. Thus, the NLR in this Seyfert 1 galaxy is very physically compact, compared to the typical NLR in Seyfert 2 galaxies.Comment: 38 pages, Latex, includes 2 figures (postscript), to appear in Ap

UVES observations of QSO 0000-2620: oxygen and zinc abundances in the Damped Ly-alpha galaxy at z_abs=3.3901

Observations of the QSO 0000-2620 with UVES spectrograph at the 8.2m ESO KUEYEN telescope are used for abundance analysis of the damped Ly-alpha system at z_{abs}=3.3901. Several Oxygen lines are identified in the Ly_alpha forest and a measure for the oxygen abundance is obtained at [O/H]=-1.85 +/- 0.1 by means of the unsaturated OI 925 A and OI 950 A lines. This represents the most accurate O measurement in a damped Ly_alpha galaxy so far. We have also detected ZnII 2026 A and CrII 2056, 2062 A redshifted at about 8900 A and found abundances [Zn/H] = -2.07 +/- 0.1 and [Cr/H]=-1.99 +/- 0.1. Furthermore, previous measurements of Fe, Si, Ni and N have been refined yielding [Fe/H]=-2.04 +/- 0.1, [Si/H]=-1.90 +/- 0.1, [Ni/H]=-2.27 +/- 0.1, and [N/H]=-2.68 +/- 0.1. The abundance of the non-refractory element zinc is the lowest among the damped Ly-alpha systems showing that the associated intervening galaxy is indeed in the early stages of its chemical evolution. The fact that the Zn abundance is identical to that of the refractory elements Fe and Cr suggests that dust grains have not formed yet. In this Damped Ly-alpha system the observed [O,S,Si/Zn,Fe,Cr] ratios, in whatever combination are taken, are close to solar (i.e 0.1-0.2 dex) and do not show the [alpha-element/Fe] enhancement observed in Milky Way stars of comparable metallicity. The observed behavior supports a galaxy evolution model characterized by either episodic or low star formation rate rather than a Milky-Way-type evolutionary model.Comment: Accepted by Ap

An Imaging and Spectroscopic Study of the z=3.38639 Damped Lyman Alpha System in Q0201+1120: Clues to Star Formation Rate at High Redshift

We present the results of a series of imaging and spectroscopic observations aimed at identifying and studying the galaxy responsible for the z = 3.38639 damped lya system in the z = 3.61 QSO Q0201+1120. We find that the DLA is part of a concentration of matter which includes at least four galaxies (probably many more) over linear comoving dimensions, greater than 5h^-1Mpc. The absorber may be a 0.7 L* galaxy at an impact parameter of 15 h^-1 kpc, but follow-up spectroscopy is still required for positive identification. The gas is turbulent, with many absorption components distributed over approximately 270 km/s and a large spin temperature, T_s greater than 4000K. The metallicity is relatively high for this redshift, Z(DLA) approximately 1/20 Z(solar). From consideration of the relative ratios of elements which have different nucleosynthetic timescales, it would appear that the last major episode of star formation in this DLA occurred at z greater than 4.3, more than approximately 500 Myr prior to the time when we observe it.Comment: Accepted for publication in Ap

Effect of variable levels of dietary cholesterol and plant sterols on the growth performance and bone metabolism in gilthead seabream (Sparus aurata) juveniles

Cholesterol is found in all animal tissues and is an important component of biological cell membranes with functions such as precursor to bile acids, hormones and vitamins. Fish meal and fish oil are cholesterol-rich ingredients. Replacement of these marine-derived ingredients by plant proteins and vegetable oils tends to reduce dietary cholesterol levels

Accuracy of prenatal culture in predicting intrapartum group B streptococcus colonization status

Objective: To evaluate the positive predictive value (PPV) of group B Streptococcus (GBS) cultures at 35–37 weeks of gestation relative to GBS colonization status at delivery. Methods: Rectovaginal swabs from 221 women at labor in four Lisbon hospitals were collected for GBS screening according to the CDC guidelines. Results: The PPV was 24.4%. IAP was administered to 100% of prenatally GBS positive women. There was no case of early onset GBS disease (EOD). Conclusions: Poor accuracy of prenatal cultures in identifying true candidates for IAP highlights the need for Portuguese clinical and laboratory guidelines to prevent EOD and antibiotic overtreatment of pregnant women

Electron temperature fluctuations in NGC 346

The existence and origin of large spatial temperature fluctuations in HII regions and planetary nebulae are assumed to explain the differences between the heavy element abundances inferred from collisionally excited and recombination lines, although this interpretation remains significantly controversial. We investigate the spatial variation in electron temperature inside NGC 346, the brightest HII region in the Small Magellanic Cloud. Long slit spectrophotometric data of high signal-to-noise were employed to derive the electron temperature from measurements derived from localized observations of the [OIII]($\lambda4959 + \lambda5007)/\lambda4363$ ratio in three directions across the nebula. The electron temperature was estimated in 179 areas of 5$^{\prime\prime}\times1.5^{\prime\prime}$ of size distributed along three different declinations. A largely homogeneous temperature distribution was found with a mean temperature of 12 269 K and a dispersion of 6.1%. After correcting for pure measurements errors, a temperature fluctuation on the plane of the sky of $t^2_{\rm s} = 0.0021$ (corresponding to a dispersion of 4.5%) was obtained, which indicates a 3D temperature fluctuation parameter of $t^2 \approx 0.008$. A large scale gradient in temperature of the order of $-5.7\pm1.3$ K arcsec$^{-1}$ was found. The magnitude of the temperature fluctuations observed agrees with the large scale variations in temperature predicted by standard photoionization models, but is too small to explain the abundance discrepancy problem. However, the possible existence of small spatial scale temperature variations is not excluded.Comment: 6 pages, 5 figures, 2 table

BBN and the Primordial Abundances

The relic abundances of the light elements synthesized during the first few minutes of the evolution of the Universe provide unique probes of cosmology and the building blocks for stellar and galactic chemical evolution, while also enabling constraints on the baryon (nucleon) density and on models of particle physics beyond the standard model. Recent WMAP analyses of the CBR temperature fluctuation spectrum, combined with other, relevant, observational data, has yielded very tight constraints on the baryon density, permitting a detailed, quantitative confrontation of the predictions of Big Bang Nucleosynthesis with the post-BBN abundances inferred from observational data. The current status of this comparison is presented, with an emphasis on the challenges to astronomy, astrophysics, particle physics, and cosmology it identifies.Comment: To appear in the Proceedings of the ESO/Arcetri Workshop on "Chemical Abundances and Mixing in Stars in the Milky Way and its Satellites", eds., L. Pasquini and S. Randich (Springer-Verlag Series, "ESO Astrophysics Symposia"

Experimental characterization and test-beam results of MACACO III Compton camera

The IRIS group at IFIC-Valencia is developing a Compton camera prototype with the aim of applying it in hadron therapy treatment monitoring. Recently, a third version of the prototype MACACO (Medical Applications CompAct COmpton camera) has been built. The system is composed of three Lanthanum (III) bromide scintillator crystals coupled to silicon photomultipliers. To improve its performance for the final application, several detectors are tested, two different silicon photomultipliers (25 and 50 um) have been chosen as possible candidates. The 25 up photodetector provided better performance in therms of dynamic range, energy resolution (5.2/ FWHM at 511 keV) and stability with temperature variations. MACACO III has also been tested in the CNA cyclotron (Seville) with 18 MeV proton beam to produce 4.439 MeV gamma rays. Data have been acquired with a graphite target in five different positions at 2.5 nA nominal beam intensity. Images with 4.439 MeV photons have been reconstructed, demonstrating the system capability to reconstruct images at energies relevant for hadron therapy. Moreover, the system has been able to distinguish 1mm displacements in the target position