1,608 research outputs found
Nesting Success of Kemp’s Ridley Sea Turtles, Lepidochelys kempi, at Rancho Nuevo, Tamaulipas, Mexico, 1982–2004
The Kemp’s ridley sea turtle, Lepidochelys kempi, was on the edge of extinction owing to a combination of intense
egg harvesting and incidental capture in commercial fishing trawls. Results from a cooperative conservation strategy initiated in 1978 between Mexico and the United States to protect and restore the Kemp’s ridley turtle at the main nesting beach at Rancho Nuevo, Tamaulipas, Mexico are
assessed. This strategy appears to be working as there are signs that the species is starting to make a recovery. Recovery indicators include: 1) increased numbers of nesting turtles, 2) increased numbers of 100+ turtle nesting aggregations (arribadas), 3) an expanding nesting season now extending from March to August, and 4) significant nighttime nesting since 2003. The population low point at Rancho Nuevo was in 1985 (706 nests) and the population began to significantly increase in 1997
(1,514 nests), growing to over 4,000 nests in 2004. The size and numbers of arribadas have increased each year since 1983 but have yet to exceed the 1,000+ mark; most
arribadas are still 200–800+ turtles
EFECTO DEL ÁCIDO CÍTRICO COMO PRETRATAMIENTO SOBRE LA ACTIVIDAD DE AGUA Y COMPORTAMIENTO DE SORCIÓN EN CALLO DE ALMEJA SECO (Nodipecten subnodosus)
En presente estudio se aplicó un tratamiento de inmersión en ácido cítrico a callo de almeja, con el objetivo de reducir el tiempo de secado de la almeja mano de león. Las muestras se sometieron a inmersión en ácido cítrico 0.1 M, durante cero (control), una y tres h. Se evaluó el efecto del pre-tratamiento de inmersión en solución ácida y la temperatura de secado (50, 60 y 70 °C), sobre la aw y el fenómeno de sorción en el callo seco. Ambas variables mostraron un efecto significativo (
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 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&
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
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
Two-dimensional multi-component photometric decomposition of CALIFA galaxies
We present a two-dimensional multi-component photometric decomposition of 404 galaxies from the Calar Alto Legacy Integral Field Area Data Release 3 (CALIFA-DR3). They represent all possible galaxies with no clear signs of interaction and not strongly inclined in the final CALIFA data release. Galaxies are modelled in the g, r, and i Sloan Digital Sky Survey (SDSS) images including, when appropriate, a nuclear point source, bulge, bar, and an exponential or broken disc component. We use a human-supervised approach to determine the optimal number of structures to be included in the fit. The dataset, including the photometric parameters of the CALIFA sample, is released together with statistical errors and a visual analysis of the quality of each fit. The analysis of the photometric components reveals a clear segregation of the structural composition of galaxies with stellar mass. At high masses (log(M⋆/M⊙) > 11), the galaxy population is dominated by galaxies modelled with a single Sérsic or a bulge+disc with a bulge-to-total (B/T) luminosity ratio B/T > 0.2. At intermediate masses (9.5 < log(M⋆/M⊙) < 11), galaxies described with bulge+disc but B/T < 0.2 are preponderant, whereas, at the low mass end (log(M⋆/M⊙)< 9.5), the prevailing population is constituted by galaxies modelled with either pure discs or nuclear point sources+discs (i.e., no discernible bulge). We obtain that 57% of the volume corrected sample of disc galaxies in the CALIFA sample host a bar. This bar fraction shows a significant drop with increasing galaxy mass in the range 9.5 < log(M⋆/M⊙) < 11.5. The analyses of the extended multi-component radial profile result in a volume-corrected distribution of 62%, 28%, and 10% for the so-called Type I (pure exponential), Type II (down-bending), and Type III (up-bending) disc profiles, respectively. These fractions are in discordance with previous findings. We argue that the different methodologies used to detect the breaks are the main cause for these differences.PostprintPeer reviewe
The Pierre Auger Observatory III: Other Astrophysical Observations
Astrophysical observations of ultra-high-energy cosmic rays with the Pierre
Auger ObservatoryComment: Contributions to the 32nd International Cosmic Ray Conference,
Beijing, China, August 201
Morpho-kinematic properties of field S0 bulges in the CALIFA survey
We study a sample of 28 S0 galaxies extracted from the integral-field
spectroscopic (IFS) survey CALIFA. We combine an accurate two-dimensional (2D)
multi-component photometric decomposition with the IFS kinematic properties of
their bulges to understand their formation scenario. Our final sample is
representative of S0s with high stellar masses ().
They lay mainly on the red sequence and live in relatively isolated
environments similar to that of the field and loose groups. We use our 2D
photometric decomposition to define the size and photometric properties of the
bulges, as well as their location within the galaxies. We perform mock
spectroscopic simulations mimicking our observed galaxies to quantify the
impact of the underlying disc on our bulge kinematic measurements (
and ). We compare our bulge corrected kinematic measurements with the
results from Schwarzschild dynamical modelling. The good agreement confirms the
robustness of our results and allows us to use bulge reprojected values of
and . We find that the photometric ( and ) and
kinematic ( and ) properties of our field S0 bulges are not
correlated. We demonstrate that this morpho-kinematic decoupling is intrinsic
to the bulges and it is not due to projection effects. We conclude that
photometric diagnostics to separate different types of bulges (disc-like vs
classical) might not be useful for S0 galaxies. The morpho-kinematics
properties of S0 bulges derived in this paper suggest that they are mainly
formed by dissipation processes happening at high redshift, but dedicated
high-resolution simulations are necessary to better identify their origin.Comment: 31 pages, 19 figures. Accepted for publication in MNRA
A histologic scoring system for prognosis of patients with Alcoholic hepatitis
BACKGROUND & AIMS: There is no histologic classification system to determine prognoses of patients with alcoholic hepatitis (AH). We identified histologic features associated with disease severity and created a histologic scoring system to predict short-term (90-day) mortality. METHODS: We analyzed data from 121 patients admitted to the Liver Unit (Hospital Clinic, Barcelona, Spain) from January 2000 to January 2008 with features of AH and developed a histologic scoring system to determine the risk of death using logistic regression. The system was tested and updated in a test set of 96 patients from 5 academic centers in the United States and Europe, and a semiquantitative scoring system called the Alcoholic Hepatitis Histologic Score (AHHS) was developed. The system was validated in an independent set of 109 patients. Interobserver agreement was evaluated by weighted κ statistical analysis. RESULTS: The degree of fibrosis, degree of neutrophil infiltration, type of bilirubinostasis, and presence of megamitochondria were independently associated with 90-day mortality. We used these 4 parameters to develop the AHHS to identify patients with a low (0-3 points), moderate (4-5 points), or high (6-9 points) risk of death within 90 days (3%, 19%, and 51%, respectively; P < .0001). The AHHS estimated 90-day mortality in the training and test sets with an area under the receiver operating characteristic value of 0.77 (95% confidence interval, 0.71-0.83). Interrater agreement values were 0.65 for fibrosis, 0.86 for bilirubinostasis, 0.60 for neutrophil infiltration, and 0.46 for megamitochondria. Interestingly, the type of bilirubinostasis predicted the development of bacterial infections. CONCLUSIONS: We identified histologic features associated with the severity of AH and developed a patient classification system that might be used in clinical decision making
Prognostic factors in left-sided endocarditis: results from the andalusian multicenter cohort
<p>Abstract</p> <p>Background</p> <p>Despite medical advances, mortality in infective endocarditis (IE) is still very high. Previous studies on prognosis in IE have observed conflicting results. The aim of this study was to identify predictors of in-hospital mortality in a large multicenter cohort of left-sided IE.</p> <p>Methods</p> <p>An observational multicenter study was conducted from January 1984 to December 2006 in seven hospitals in Andalusia, Spain. Seven hundred and five left-side IE patients were included. The main outcome measure was in-hospital mortality. Several prognostic factors were analysed by univariate tests and then by multilogistic regression model.</p> <p>Results</p> <p>The overall mortality was 29.5% (25.5% from 1984 to 1995 and 31.9% from 1996 to 2006; Odds Ratio 1.25; 95% Confidence Interval: 0.97-1.60; p = 0.07). In univariate analysis, age, comorbidity, especially chronic liver disease, prosthetic valve, virulent microorganism such as <it>Staphylococcus aureus</it>, <it>Streptococcus agalactiae </it>and fungi, and complications (septic shock, severe heart failure, renal insufficiency, neurologic manifestations and perivalvular extension) were related with higher mortality. Independent factors for mortality in multivariate analysis were: Charlson comorbidity score (OR: 1.2; 95% CI: 1.1-1.3), prosthetic endocarditis (OR: 1.9; CI: 1.2-3.1), <it>Staphylococcus aureus </it>aetiology (OR: 2.1; CI: 1.3-3.5), severe heart failure (OR: 5.4; CI: 3.3-8.8), neurologic manifestations (OR: 1.9; CI: 1.2-2.9), septic shock (OR: 4.2; CI: 2.3-7.7), perivalvular extension (OR: 2.4; CI: 1.3-4.5) and acute renal failure (OR: 1.69; CI: 1.0-2.6). Conversely, <it>Streptococcus viridans </it>group etiology (OR: 0.4; CI: 0.2-0.7) and surgical treatment (OR: 0.5; CI: 0.3-0.8) were protective factors.</p> <p>Conclusions</p> <p>Several characteristics of left-sided endocarditis enable selection of a patient group at higher risk of mortality. This group may benefit from more specialised attention in referral centers and should help to identify those patients who might benefit from more aggressive diagnostic and/or therapeutic procedures.</p
Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study
[EN] Regulated expression of the Ena1 Na+-ATPase is a crucial event for adaptation to high
salt and/or alkaline pH stress in the budding yeast Saccharomyces cerevisiae. ENA1
expression is under the control of diverse signaling pathways, including that mediated
by the calcium-regulatable protein phosphatase calcineurin and its downstream
transcription factor Crz1. We present here a quantitative study of the expression of
Ena1 in response to alkalinization of the environment and we analyze the contribution
of Crz1 to this response. Experimental data and mathematical models substantiate the
existence of two stress-responsive Crz1-binding sites in the ENA1 promoter and
estimate that the contribution of Crz1 to the early response of the ENA1 promoter is
about 60%. The models suggest the existence of a second input with similar kinetics,
which would be likely mediated by high pH-induced activation of the Snf1 kinase.This work was supported by grants BFU2011-30197-C3-01, BFU2014-54591-C2-1-P and EUI2009-04147 (SysMo2) to JA. (Ministry of Industry and Competitivity, Spain, and Fondo Europeo de Desarrollo Regional [FEDER]). JA is the recipient of an Ajut 2014SGR-4 award (Generalitat de Catalunya). DC was recipient of a predoctoral fellowship from the Spanish Ministry of Education. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Petrezsélyová, S.; López-Malo, M.; Canadell, D.; Roque, A.; Serra-Cardona, A.; Marques Romero, MC.; Vilaprinyó, E.... (2016). Regulation of the Na+/K+-ATPase Ena1 Expression by Calcineurin/Crz1 under High pH Stress: A Quantitative Study. PLoS ONE. 11(6):e0158424-e0158424. https://doi.org/10.1371/journal.pone.0158424Se0158424e015842411
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