608 research outputs found
A genetic linkage map of the hermaphrodite teleost fish Sparus aurata L.
The gilthead sea bream (Sparus aurata L.) is a marine fish of great importance for fisheries and aquaculture. It has also a peculiar sex-determination system, being a protandrous hermaphrodite. Here we
report the construction of a first-generation genetic linkage map for S. aurata, based on 204 microsatellite
markers. Twenty-six linkage groups (LG) were found. The total map length was 1241.9 cM. The ratio
between sex-specific map lengths was 1:1.2 (male:female). Comparison with a preliminary radiation hybrid
(RH) map reveals a good concordance, as all markers located in a single LG are located in a single RH
group, except for Ad-25 and CId-31. Comparison with the Tetraodon nigroviridis genome revealed a considerable number of evolutionary conserved regions (ECRs) between the two species. The mean size of
ECRs was 182 bp (sequence identity 60–90%). Forty-one ECRs have a known chromosomal location in the
pufferfish genome. Despite the limited number of anchoring points, significant syntenic relationships were
found. The linkage map presented here provides a robust comparative framework for QTL analysis in S.
aurata and is a step toward the identification of genetic loci involved both in the determination of economically important traits and in the individual timing of sex reversal
J-PLUS: Identification of low-metallicity stars with artificial neural networks using SPHINX
We present a new methodology for the estimation of stellar atmospheric
parameters from narrow- and intermediate-band photometry of the Javalambre
Photometric Local Universe Survey (J-PLUS), and propose a method for target
pre-selection of low-metallicity stars for follow-up spectroscopic studies.
Photometric metallicity estimates for stars in the globular cluster M15 are
determined using this method. By development of a neural-network-based
photometry pipeline, we aim to produce estimates of effective temperature,
, and metallicity, [Fe/H], for a large subset of stars in the
J-PLUS footprint. The Stellar Photometric Index Network Explorer, SPHINX, is
developed to produce estimates of and [Fe/H], after training on a
combination of J-PLUS photometric inputs and synthetic magnitudes computed for
medium-resolution (R ~ 2000) spectra of the Sloan Digital Sky Survey. This
methodology is applied to J-PLUS photometry of the globular cluster M15.
Effective temperature estimates made with J-PLUS Early Data Release photometry
exhibit low scatter, \sigma() = 91 K, over the temperature range
4500 < (K) < 8500. For stars from the J-PLUS First Data Release
with 4500 < (K) < 6200, 85 3% of stars known to have [Fe/H]
<-2.0 are recovered by SPHINX. A mean metallicity of [Fe/H]=-2.32 0.01,
with a residual spread of 0.3 dex, is determined for M15 using J-PLUS
photometry of 664 likely cluster members. We confirm the performance of SPHINX
within the ranges specified, and verify its utility as a stand-alone tool for
photometric estimation of effective temperature and metallicity, and for
pre-selection of metal-poor spectroscopic targets.Comment: 18 pages, 12 figure
The use of Pd catalysts on carbon-based structured materials for the catalytic hydrogenation of bromates in different types of water
[EN] The aim of this work is to study the activity of new Pd catalysts, supported on two different nano structured carbon materials, for bromate catalytic hydrogenation. The influence of the support has been studied, obtaining the best results with a palladium catalyst supported on carbon nanofibers (CNF) grown in sintered metal fibers (SMF). The results have shown the importance of the catalyst support in order to minimize the mass-transfer limitations ensuring an efficient catalyst use. In this way the most active catalysts are those with a mesoporous structure containing high dispersed Pd nanoparticles. The activity of this catalyst for bromate reduction has been tested in different types of water, namely, distilled water, natural water and industrial wastewater. It has been shown that the catalyst activity depends on the water matrix and bromate reduction rate depends on the hydrogen partial pressure. The potential use of the catalyst has been studied in a continuous reactor. It has been observed that the catalyst is active without any important deactivation at least during 100 h of reaction, but is necessary to avoid salt precipitation and plugging problems.The authors thank the European Union (European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement no. 226347 Project) for financial support. A.E. Palomares also acknowledges the support from the Spanish Government through the project MAT2012-38567-C02-01.Palomares Gimeno, AE.; Franch Martí, C.; Yuranova, T.; Kiwi-Minsker, L.; Garcia Bordeje, JE.; Derrouiche, S. (2014). The use of Pd catalysts on carbon-based structured materials for the catalytic hydrogenation of bromates in different types of water. Applied Catalysis B: Environmental. 146:186-191. https://doi.org/10.1016/j.apcatb.2013.02.056S18619114
Stellar populations of galaxies in the ALHAMBRA survey up to . I. MUFFIT: A Multi-Filter Fitting code for stellar population diagnostics
We present MUFFIT, a new generic code optimized to retrieve the main stellar
population parameters of galaxies in photometric multi-filter surveys, and we
check its reliability and feasibility with real galaxy data from the ALHAMBRA
survey. Making use of an error-weighted -test, we compare the
multi-filter fluxes of galaxies with the synthetic photometry of mixtures of
two single stellar populations at different redshifts and extinctions, to
provide through a Monte Carlo method the most likely range of stellar
population parameters (mainly ages and metallicities), extinctions, redshifts,
and stellar masses. To improve the diagnostic reliability, MUFFIT identifies
and removes from the analysis those bands that are significantly affected by
emission lines. We highlight that the retrieved age-metallicity locus for a
sample of early-type galaxies in ALHAMBRA at different stellar
mass bins are in very good agreement with the ones from SDSS spectroscopic
diagnostics. Moreover, a one-to-one comparison between the redshifts, ages,
metallicities, and stellar masses derived spectroscopically for SDSS and by
MUFFIT for ALHAMBRA reveals good qualitative agreements in all the parameters.
In addition, and using as input the results from photometric-redshift codes,
MUFFIT improves the photometric-redshift accuracy by -, and it
also detects nebular emissions in galaxies, providing physical information
about their strengths. Our results show the potential of multi-filter galaxy
data to conduct reliable stellar population studies with the appropiate
analysis techniques, as MUFFIT.Comment: 31 pages, 18 figures, accepted for publication in A&
J-PLUS: analysis of the intracluster light in the Coma cluster
The intracluster light (ICL) is a luminous component of galaxy clusters
composed of stars that are gravitationally bound to the cluster potential but
do not belong to the individual galaxies. Previous studies of the ICL have
shown that its formation and evolution are intimately linked to the
evolutionary stage of the cluster. Thus, the analysis of the ICL in the Coma
cluster will give insights into the main processes driving the dynamics in this
highly complex system. Using a recently developed technique, we measure the ICL
fraction in Coma at several wavelengths, using the J-PLUS unique filter system.
The combination of narrow- and broadband filters provides valuable information
on the dynamical state of the cluster, the ICL stellar types, and the
morphology of the diffuse light. We use the Chebyshev-Fourier Intracluster
Light Estimator (CICLE) to disentangle the ICL from the light of the galaxies,
and to robustly measure the ICL fraction in seven J-PLUS filters. We obtain the
ICL fraction distribution of the Coma cluster at different optical wavelengths,
which varies from , showing the highest values in the narrowband
filters J0395, J0410, and J0430. This ICL fraction excess is distinctive
pattern recently observed in dynamically active clusters (mergers), indicating
a higher amount of bluer stars in the ICL compared to the cluster galaxies.
Both the high ICL fractions and the excess in the bluer filters are indicative
of a merging state. The presence of younger/lower-metallicity stars the ICL
suggests that the main mechanism of ICL formation for the Coma cluster is the
stripping of the stars in the outskirts of infalling galaxies and, possibly,
the disruption of dwarf galaxies during past/ongoing mergers.Comment: 10 pages, 3 figures, 1 table. Accepted for publication in A&
Personality in interaction: how the Big Five relate to the reception of interactive narratives
In this study, we explore how users’ personalities affect their responses to interactive narratives. In particular, we analyze the relationship between personality traits and relevant variables in narrative reception: identification with characters, enjoyment, self-perceived physiological sensations, emotional experience and content. Experimental participants (N=310) answered the NEO- FFI personality questionnaire and watched a movie in one of four experimental conditions that combined modality (interactive vs. linear) and content (happy vs. tragic end). Results suggest that personality traits influence users’ responses to fiction and interactivity.En este trabajo, exploramos como la personalidad de los usuarios afecta su respuesta a las narrativas interactivas. En particular, analizamos la relación entre los rasgos de personalidad y variables relevantes en recepción de narrativas: identificación con los personajes, disfrute, sensaciones fisiológicas, emociones y contenido. Los participantes (N=310) respondieron el inventario NEO-FFI de la personalidad y vieron una película en una de las cuatro condiciones experimentales en las que se combinó modalidad (interactiva vs. no interactiva) y contenido (final feliz vs. trágico). Los resultados sugieren que la personalidad influye las respuestas de los usuarios a las ficciones y a la interactividad
High redshift galaxies in the ALHAMBRA survey: I. selection method and number counts based on redshift PDFs
Context. Most observational results on the high redshift restframe UV-bright
galaxies are based on samples pinpointed using the so called dropout technique
or Ly-alpha selection. However, the availability of multifilter data allows now
replacing the dropout selections by direct methods based on photometric
redshifts. In this paper we present the methodology to select and study the
population of high redshift galaxies in the ALHAMBRA survey data. Aims. Our aim
is to develop a less biased methodology than the traditional dropout technique
to study the high redshift galaxies in ALHAMBRA and other multifilter data.
Thanks to the wide area ALHAMBRA covers, we especially aim at contributing in
the study of the brightest, less frequent, high redshift galaxies. Methods. The
methodology is based on redshift probability distribution functions (zPDFs). It
is shown how a clean galaxy sample can be obtained by selecting the galaxies
with high integrated probability of being within a given redshift interval.
However, reaching both a complete and clean sample with this method is
challenging. Hence, a method to derive statistical properties by summing the
zPDFs of all the galaxies in the redshift bin of interest is introduced.
Results. Using this methodology we derive the galaxy rest frame UV number
counts in five redshift bins centred at z=2.5, 3.0, 3.5, 4.0, and 4.5, being
complete up to the limiting magnitude at m_UV(AB)=24. With the wide field
ALHAMBRA data we especially contribute in the study of the brightest ends of
these counts, sampling well the surface densities down to m_UV(AB)=21-22.
Conclusions. We show that using the zPDFs it is easy to select a clean sample
of high redshift galaxies. We also show that statistical analysis of the
properties of galaxies is better done using a probabilistic approach, which
takes into account both the incompleteness and contamination in a natural way.Comment: 16 pages, 11 figures; Accepted for A&A; language correcte
J-PLUS: A wide-field multi-band study of the M15 globular cluster. Evidence of multiple stellar populations in the RGB
The Javalambre Photometric Local Universe Survey (J-PLUS) provides wide
field-of-view images in 12 narrow, intermediate and broad-band filters
optimized for stellar photometry. Here we have applied J-PLUS data for the
first time for the study of Galactic GCs using science verification data
obtained for the very metal-poor GC M\,15. Our J-PLUS data provide
low-resolution spectral energy distributions covering the near-UV to the
near-IR, allowing us to search for MPs based on pseudo-spectral fitting
diagnostics. J-PLUS CMDs are found to be particularly useful to search for
splits in the sequences formed by the upper red giant branch (RGB) and
asymptotic giant branch (AGB) stars. We interpret these split sequences as
evidence for the presence of MPs. This demonstrates that the J-PLUS survey will
have sufficient spatial coverage and spectral resolution to perform a large
statistical study of GCs through multi-band photometry in the coming years.Comment: 11 pages, 11 figures. Accepted for publication @ A&
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