2,825 research outputs found
Tratamiento asistido por artroscopia de las fracturas de radio distal
ResumenLa artroscopia proporciona una valoración directa de la superficie articular y permite detectar lesiones asociadas en las fracturas de la extremidad distal del radio. Su incorporación al tratamiento de estas fracturas ha supuesto un mejor control de la reducción de los trazos articulares, pero se trata de una técnica compleja que aún no está generalizada entre la mayoría de los cirujanos ortopédicos y/o de la mano y la muñeca.Se realiza una revisión y actualización de las ventajas, las indicaciones, las claves técnicas, los resultados y los datos científicos de su utilidad para el tratamiento de las fracturas del radio distal.AbstractArthroscopy provides a direct evaluation of the joint surface and enables associated injuries to be detected in fractures of the distal end of the radius. Although its incorporation into the treatment of these fractures has led to a better control in the reduction of joint traces, it is a complicated technique that is still not in general use by the majority of orthopaedic and/or hand and wrist surgeons.A review is presented here, as well as an update of the advantages, indications, the key techniques, results, and scientific data of its use in the treatment of distal radius fractures
A Multi-wavelength analysis of M81: insight on the nature of Arp's loop
Context: The optical ring like structure detected by Arp (1965) around M81
(commonly referenced as "Arp's loop") represents one of the most spectacular
feature observed in nearby galaxies. Arp's loop is commonly interpreted as a
tail resulting from the tidal interaction between M81 and M82. However, since
its discovery the nature of this feature has remained controversial. Aims: Our
primary purpose was to identify the sources of optical and infrared emission
observed in Arp's loop. Methods: The morphology of the Arp's loop has been
investigated with deep wide-field optical images. We also measured its colors
using IRAS and Spitzer-MIPS infrared images and compared them with those of the
disk of M81 and Galactic dust cirrus that fills the area where M81 is located.
Results: Optical images reveal that this peculiar object has a filamentary
structure characterized by many dust features overlapping M81's field. The
ratios of far-infrared fluxes and the estimated dust-to-gas ratios indicate the
infrared emission of Arp's loop is dominated by the contribution of cold dust
that is most likely from Galactic cirrus. Conclusions: The above results
suggest that the light observed at optical wavelengths is a combination of
emission from i) a few recent star forming regions located close to M81, where
both bright UV complexes and peaks in the HI distribution are found, ii) the
extended disk of M81 and iii) scattered light from the same Galactic cirrus
that is responsible for the bulk of the far infrared emission.Comment: 7 pages, 7 figures, accepted for publication by A&
Assessment of Health benefits from a nutrition program aimed at inmates with cardiovascular risk factors at Huelva prison
ABSTRACT Background: Diet and lifestyle are important factors in improving cardiovascular health and preventing chronic diseases
Percepción de las conductas contrarias a la convivencia en el profesorado de Educación Secundaria Obligatoria
The learning environment influences the teaching-learning process as well as the welfare of the educational community members. Moreover, it is a question addressed by numerous scientific studies.The main objective of this research project is to describe and analyze the main conflicting behaviors of students in mandatory secondary education and relate to variables such as the location of institutions and participants, teacher gender, years of seniority as a teacher, management position and educational stage.In the research we worked with a sample of 147 teachers of Physical Education actively practicing in mandatory secondary education schools. Participants completed two ad hoc questionnaires to evaluate students´ problem behaviour at school. We followed the ‘factor analysis’ approach and finally we obtained five behavioural factors. We also applied the chi-squared test or so-called ‘Exact test of Fisher’ to associate these behaviours to other relevant variables. We conclude that the most frequent unruly behaviour are disruptive attitude and verbal abuse. Behaviours related to “Defiance and bullying” are more likely to happen when teachers are women. Less experienced teachers recorded more “attention deficit” behaviours in their classroom. Teachers having experience on management positions had to deal less often with behaviours related to “attention deficit” and “misuse of materials”.La convivencia escolar en los centros educativos influye en el proceso de enseñanza-aprendizaje, así como en el bienestar de los miembros de la comunidad educativa. Además, es una cuestión abordada por numerosos estudios científicos. El objetivo principal del presente trabajo es describir y analizar las principales conductas contrarias a la convivencia en Educación Secundaria Obligatoria y relacionarlas con variables como la ciudad de procedencia, género del profesor, antigüedad en el cuerpo, desempeño de cargo directivo y ciclo educativo.Los participantes son 147 profesores de Educación Física que ejercen activamente la profesión en centros de Educación Secundaria Obligatoria. Dicha muestra cumplimentó individual y expresamente dos cuestionarios diseñados “ad hoc” para evaluar las conductas contrarias a la convivencia en el alumnado. A las conductas se les aplicó la técnica de análisis factorial obteniendo finalmente cinco factores de conducta. Además, se aplicó chi-cuadrado o test exacto de Fisher para relacionar las conductas con otras variables de interés.Se concluye que las conductas contrarias a la convivencia más frecuentes son las disruptivas y las agresiones verbales. Respecto al género del profesorado las conductas pertenecientes a “desafío y acoso” son más frecuentes cuando la profesora es mujer que cuando el profesor es hombre. Cuantos menos años lleva el profesor en el cuerpo, más frecuentes son las conductas pertenecientes a “déficit de atención”. Las conductas pertenecientes a “déficit de atención” y “mal uso de materiales” son más frecuentes cuando el profesor no desempeña ni ha desempeñado cargo directivo alguno.
The ALHAMBRA survey : Estimation of the clustering signal encoded in the cosmic variance
The relative cosmic variance () is a fundamental source of
uncertainty in pencil-beam surveys and, as a particular case of count-in-cell
statistics, can be used to estimate the bias between galaxies and their
underlying dark-matter distribution. Our goal is to test the significance of
the clustering information encoded in the measured in the ALHAMBRA
survey. We measure the cosmic variance of several galaxy populations selected
with band luminosity at as the intrinsic dispersion in
the number density distribution derived from the 48 ALHAMBRA subfields. We
compare the observational with the cosmic variance of the dark
matter expected from the theory, . This provides an
estimation of the galaxy bias . The galaxy bias from the cosmic variance is
in excellent agreement with the bias estimated by two-point correlation
function analysis in ALHAMBRA. This holds for different redshift bins, for red
and blue subsamples, and for several band luminosity selections. We find
that increases with the band luminosity and the redshift, as expected
from previous work. Moreover, red galaxies have a larger bias than blue
galaxies, with a relative bias of . Our results
demonstrate that the cosmic variance measured in ALHAMBRA is due to the
clustering of galaxies and can be used to characterise the affecting
pencil-beam surveys. In addition, it can also be used to estimate the galaxy
bias from a method independent of correlation functions.Comment: Astronomy and Astrophysics, in press. 9 pages, 4 figures, 3 table
The ALHAMBRA survey: evolution of galaxy spectral segregation
We study the clustering of galaxies as a function of spectral type and
redshift in the range using data from the Advanced Large
Homogeneous Area Medium Band Redshift Astronomical (ALHAMBRA) survey. The data
cover 2.381 deg in 7 fields, after applying a detailed angular selection
mask, with accurate photometric redshifts [] down to
. From this catalog we draw five fixed number density,
redshift-limited bins. We estimate the clustering evolution for two different
spectral populations selected using the ALHAMBRA-based photometric templates:
quiescent and star-forming galaxies. For each sample, we measure the real-space
clustering using the projected correlation function. Our calculations are
performed over the range Mpc, allowing us to find a
steeper trend for Mpc, which is especially clear for
star-forming galaxies. Our analysis also shows a clear early differentiation in
the clustering properties of both populations: star-forming galaxies show
weaker clustering with evolution in the correlation length over the analysed
redshift range, while quiescent galaxies show stronger clustering already at
high redshifts, and no appreciable evolution. We also perform the bias
calculation where similar segregation is found, but now it is among the
quiescent galaxies where a growing evolution with redshift is clearer. These
findings clearly corroborate the well known colour-density relation, confirming
that quiescent galaxies are mainly located in dark matter halos that are more
massive than those typically populated by star-forming galaxies.Comment: 14 pages, 9 figures, accepted by Ap
The ALHAMBRA survey : band luminosity function of quiescent and star-forming galaxies at by PDF analysis
Our goal is to study the evolution of the band luminosity function (LF)
since using ALHAMBRA data. We used the photometric redshift and the
band selection magnitude probability distribution functions (PDFs) of those
ALHAMBRA galaxies with mag to compute the posterior LF. We
statistically studied quiescent and star-forming galaxies using the template
information encoded in the PDFs. The LF covariance matrix in
redshift-magnitude-galaxy type space was computed, including the cosmic
variance. That was estimated from the intrinsic dispersion of the LF
measurements in the 48 ALHAMBRA sub-fields. The uncertainty due to the
photometric redshift prior is also included in our analysis. We modelled the LF
with a redshift-dependent Schechter function affected by the same selection
effects than the data. The measured ALHAMBRA LF at and the
evolving Schechter parameters both for quiescent and star-forming galaxies
agree with previous results in the literature. The estimated redshift evolution
of is and , and of is
and . The measured faint-end slopes are and . We find a significant
population of faint quiescent galaxies, modelled by a second Schechter function
with slope . We find a factor decrease in the
luminosity density of star-forming galaxies, and a factor
increase in the of quiescent ones since , confirming the continuous
build-up of the quiescent population with cosmic time. The contribution of the
faint quiescent population to increases from 3% at to 6% at .
The developed methodology will be applied to future multi-filter surveys such
as J-PAS.Comment: Accepted for publication in Astronomy and Astrophysics. 25 pages, 20
figures, 7 table
From traits to life-history strategies: Deconstructing fish community composition across European seas
En prens
Aperture effects on the oxygen abundance determinations from CALIFA data
This paper aims at providing aperture corrections for emission lines in a
sample of spiral galaxies from the Calar Alto Legacy Integral Field Area Survey
(CALIFA) database. In particular, we explore the behavior of the
log([OIII]5007/Hbeta)/([NII]6583/Halpha) (O3N2) and log[NII]6583/Halpha (N2)
flux ratios since they are closely connected to different empirical
calibrations of the oxygen abundances in star forming galaxies.
We compute median growth curves of Halpha, Halpha/Hbeta, O3N2 and N2 up to
2.5R_50 and 1.5 disk R_eff. The growth curves simulate the effect of observing
galaxies through apertures of varying radii. The median growth curve of the
Halpha/Hbeta ratio monotonically decreases from the center towards larger
radii, showing for small apertures a maximum value of ~10% larger than the
integrated one. The median growth curve of N2 shows a similar behavior,
decreasing from the center towards larger radii. No strong dependence is seen
with the inclination, morphological type and stellar mass for these growth
curves. Finally, the median growth curve of O3N2 increases monotonically with
radius. However, at small radii it shows systematically higher values for
galaxies of earlier morphological types and for high stellar mass galaxies.
Applying our aperture corrections to a sample of galaxies from the SDSS
survey at 0.02<=z<=0.3 shows that the average difference between fiber-based
and aperture corrected oxygen abundances, for different galaxy stellar mass and
redshift ranges, reaches typically to ~11%, depending on the abundance
calibration used. This average difference is found to be systematically biased,
though still within the typical uncertainties of oxygen abundances derived from
empirical calibrations. Caution must be exercised when using observations of
galaxies for small radii (e.g. below 0.5R_eff) given the high dispersion shown
around the median growth curves.Comment: Accepted for publication in Ap
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