570 research outputs found
La eficacia de la prisión preventiva en los delitos de corrupción
Este estudio se propuso como objetivo general establecer las circunstancias que generan la ineficacia de la prisión preventiva, como medida cautelar personal, en el sistema anticorrupción de Lima Centro, aplicando un método aplicativo, descriptivo, explicativo, la población se formó con 59 colaboradores, quienes al absolver la encuesta asumieron en un 90% que las circunstancias afectan la eficacia de la prisión preventiva en los delitos de corrupción de funcionarios son de dos tipos: de índole legal: por cuanto la trasforman en una mecanismo para ejercer la prevención general en la sociedad y, en la administración de justicia por cuanto apareja despilfarro de recursos públicos y pérdida de tiempo para el Fiscal y el Juez de la Investigación Preparatoria
Análisis del desempeño docente y logro de las competencias en TOK de los estudiantes del COAR-IB en el contexto de pandemia COVID-19
El contexto de pandemia ha afectado de manera directa a la educación
presencial. La educación que se ha desarrollo en el año 2020 y 2021 ha
presentado dificultades en los estudiantes en cuanto al logro de las
competencias y también en el desempeño docente. Ante esta problemática se
ha realizado la investigación teniendo como objetivo: analizar la relación entre el
desempeño docente y el logro de las competencias en TOK de los estudiantes
del COAR-IB. La población es de 250 estudiantes de quinto grado del COARIB,
conforman COAR Ancash, Ica y San Martín. Se emplea la metodología de
enfoque cualitativo, nivel descriptivo, tipo pura o básica, diseño teoría
fundamental y con el método inductivo y análisis. Esto ha generado como
resultado que, el desempeño docente del área de TOK es la más óptima para
los estudiantes que asisten a las clases sincrónicas y para los estudiantes con
materiales impresos es regular; y en cuanto al logro de las competencias los
estudiantes en área de TOK presentan grandes dificultades. Se llega a la
conclusión, que sí existe una relación significativa entre el desempeño docente
y el logro de las competencias
Quantified HI Morphology I: Multi-Wavelengths Analysis of the THINGS Galaxies
Galaxy evolution is driven to a large extent by interactions and mergers with
other galaxies and the gas in galaxies is extremely sensitive to the
interactions. One method to measure such interactions uses the quantified
morphology of galaxy images. Well-established parameters are Concentration,
Asymmetry, Smoothness, Gini, and M20 of a galaxy image. Thus far, the
application of this technique has mostly been restricted to restframe
ultra-violet and optical images. However, with the new radio observatories
being commissioned (MeerKAT, ASKAP, EVLA, WSRT/APERTIF, and ultimately SKA), a
new window on the neutral atomic hydrogen gas (HI) morphology of a large
numbers of galaxies will open up. The quantified morphology of gas disks of
spirals can be an alternative indicator of the level and frequency of
interaction. The HI in galaxies is typically spatially more extended and more
sensitive to low-mass or weak interactions. In this paper, we explore six
morphological parameters calculated over the extent of the stellar (optical)
disk and the extent of the gas disk for a range of wavelengths spanning UV,
Optical, Near- and Far-Infrared and 21 cm (HI) of 28 galaxies from The HI
Nearby Galaxy Survey (THINGS). Though the THINGS sample is small and contains
only a single ongoing interaction, it spans both non-interacting and
post-interacting galaxies with a wealth of multi-wavelength data. We find that
the choice of area for the computation of the morphological parameters is less
of an issue than the wavelength at which they are measured. The signal of
interaction is as good in the HI as in any of the other wavelengths in which
morphology has been used to trace the interaction rate to date, mostly
star-formation dominated ones (near- and far-ultraviolet). The Asymmetry and
M20 parameters are the ones which show the most promise as tracers of
interaction in 21 cm line observations.Comment: 16 pages, 11 figure, table 1, accepted by MNRAS, appendix not
include
Revisiting the Hubble sequence in the SDSS DR7 spectroscopic sample: a publicly available bayesian automated classification
We present an automated morphological classification in 4 types
(E,S0,Sab,Scd) of ~700.000 galaxies from the SDSS DR7 spectroscopic sample
based on support vector machines. The main new property of the classification
is that we associate to each galaxy a probability of being in the four
morphological classes instead of assigning a single class. The classification
is therefore better adapted to nature where we expect a continuos transition
between different morphological types. The algorithm is trained with a visual
classification and then compared to several independent visual classifications
including the Galaxy Zoo first release catalog. We find a very good correlation
between the automated classification and classical visual ones. The compiled
catalog is intended for use in different applications and can be downloaded at
http://gepicom04.obspm.fr/sdss_morphology/Morphology_2010.html and soon from
the CasJobs database.Comment: A&A in press, english corrections from language editor adde
Parametrising arbitrary galaxy morphologies: potentials and pitfalls
We demonstrate that morphological observables (e.g. steepness of the radial
light profile, ellipticity, asymmetry) are intertwined and cannot be measured
independently of each other. We present strong arguments in favour of
model-based parametrisation schemes, namely reliability assessment,
disentanglement of morphological observables, and PSF modelling. Furthermore,
we demonstrate that estimates of the concentration and Sersic index obtained
from the Zurich Structure & Morphology catalogue are in excellent agreement
with theoretical predictions. We also demonstrate that the incautious use of
the concentration index for classification purposes can cause a severe loss of
the discriminative information contained in a given data sample. Moreover, we
show that, for poorly resolved galaxies, concentration index and M_20 suffer
from strong discontinuities, i.e. similar morphologies are not necessarily
mapped to neighbouring points in the parameter space. This limits the
reliability of these parameters for classification purposes. Two-dimensional
Sersic profiles accounting for centroid and ellipticity are identified as the
currently most reliable parametrisation scheme in the regime of intermediate
signal-to-noise ratios and resolutions, where asymmetries and substructures do
not play an important role. We argue that basis functions provide good
parametrisation schemes in the regimes of high signal-to-noise ratios and
resolutions. Concerning Sersic profiles, we show that scale radii cannot be
compared directly for profiles of different Sersic indices. Furthermore, we
show that parameter spaces are typically highly nonlinear. This implies that
significant caution is required when distance-based classificaton methods are
used.Comment: 18 pages, 13 figure
Intrinsic colors and ages of extremely red elliptical galaxies at high redshift
In order to know the formation epoch of the oldest elliptical galaxies as a
function of mass and observed redshift, a statistical analysis for 333
extremely red objects (EROs) classified as old galaxies (OGs) at 0.8<z<2.3 is
carried out. Once we get M_V and (B-V) at rest for each galaxy, we calculate
the average variation of this intrinsic color with redshift and derive the
average age through a synthesis model (the code for the calculation of the age
has been made publicly available). The average gradient of the (B-V) color at
rest of EROs/OGs is 0.07-0.10 Gyr^{-1} for a fixed luminosity. The stars in
these extremely red elliptical galaxies were formed when the Universe was ~2
Gyr old on average. We have not found a significant enough dependence on the
observed redshift and stellar mass: dt_{formation}/dt_{observed}=-0.46+/-0.32,
dt_{formation}/(d log_10 M_*)=-0.81+/-0.98 Gyr. This fits a scenario in which
the stellar formation of the objects that we denominate as EROs-OGs is more
intense at higher redshifts, at which the stellar populations of the most
massive galaxies form earlier than or at the same time as less massive
galaxies.Comment: accepted to be published in A
La importancia de la comunicación externa del Centro Juvenil de Medio Cerrado Lima – 01 para mejorar su percepción frente a padres de familia de 35 a 55 años pertenecientes a los sectores B y C
La presente investigación tiene como objetivo principal analizar cómo es la comunicación externa del Centro Juvenil de Medio Cerrado Lima –01 para informar acerca de la reinserción social de los adolescentes de 14 a 18 años en la sociedad. Determinar la comunicación externa, ayudará a conocer si la ciudadanía está correctamente informada sobre la labor que desarrolla el centro con los adolescentes infractores para reinsertarlos adecuadamente a la sociedad. Se realizó una investigación cualitativa y cuantitativa, donde se aplicaron encuestas, entrevistas y el método de observación, a fin de obtener una vista amplia sobre el tema. Lo que nos pertimió conocer que la sociedad tiene un mal concepto sobre los adolescentes infractores y de la labor que realiza el Centro Juvenil de Medio Cerrado Lima –01, por dos puntos: desconocen del tema y consideran que los adolescentes reincidirán en actos delictivos.Campus Lima Centr
Adaptive Optics Rest-Frame V-band Imaging of Lyman Break Galaxies at z~3: High-surface Density Disk-like Galaxies ?
In order to reveal the rest-frame V-band morphology of galaxies at z~3, we
conducted AO-assisted K-band imaging observations of z~3 LBGs with Mv*-0.5 to
Mv*+3.0 mag. LBGs brighter than Mv* have larger rHL (0.40") than the fainter
LBGs (0.23") on average, and there is no bright LBGs with a small rHL. The LBGs
brighter than Mv* have red rest-frame U-V colors (average of 0.2 mag) and most
of the fainter LBGs show blue rest-frame U-V colors (average of -0.4 mag). The
K-band peaks of some of the LBGs brighter than K=22.0 mag show significant
shift from those in the optical images. The images of all but one of the LBGs
with K<21.5 mag are fitted well with Sersic profile with n index less than 2,
similar to disk galaxies in the local universe. Assuming that the LBGs have a
disk-shape, we compared their size-luminosity and size-stellar mass relation
with those of z=0 and z=1 disk galaxies. The LBGs are brighter than z=0 and z=1
disk galaxies at the same effective radius. The rest-frame V-band surface
brightness of the LBGs are 2.2-2.9 mag and 1.2-1.9 mag brighter than the disk
galaxies at z=0 and z=1, respectively. The size-stellar mass relation of the
LBGs shows that the effective radii of the LBGs do not depend on their stellar
mass. For the LBGs brighter than Mv*, the average surface stellar mass density
is 3-6 times larger than those of the z=0 and z=1 disk galaxies. We also
examine the profiles of the serendipitously observed DRGs. They are also fitted
with the Sersic profiles with n<2. The implications of the dominance of n<2
population among galaxies at z~3 and the presence of the high surface stellar
mass density disk systems are discussed.Comment: Accepted for publication in Astrophysical Journal Supplement. 38
pages, 26 postscript figures. Original version with high resolution figures
is available from http://www.naoj.org/staff/akiyama/papers/LBG_AO.pd
The Structures of Distant Galaxies V: The Evolution of Galaxy Structure in Stellar Mass at z < 1
Galaxy structure and morphology is nearly always studied using the light
originating from stars, however ideally one is interested in measuring
structure using the stellar mass distribution. Not only does stellar mass trace
out the underlying distribution of matter, it also minimises the effects of
star formation and dust on the appearance and structure of a galaxy. We present
in this paper a study of the stellar mass distributions and structures of
galaxies at z<1 as found within the GOODS fields. We use pixel by pixel
K-corrections to construct stellar mass and mass-to-light ratio maps of 560
galaxies of known morphology at magnitudes z_{850}<24. We measure structural
and size parameters using these stellar mass maps, as well as on ACS BViz band
imaging. This includes investigating the structural CAS-Gini-M_{20} parameters
and half-light radius for each galaxy. We compare structural parameters and
half-light radii in the ACS z_{850}-band and stellar mass maps, finding no
systematic bias introduced by measuring galaxy sizes in z_{850}. We furthermore
investigate relations between structural parameters in the ACS BViz bands and
stellar mass maps, and compare our result to previous morphological studies.
Combinations of various parameters in stellar mass generally reveal clear
separations between early and late type morphologies, but cannot easily
distinguish between star formation and dynamically disturbed systems. We also
show that while ellipticals and early-type spirals have fairly constant CAS
values at z<1 we find a tendency for late-type spiral and peculiar
morphological types to have a higher A(M_{*}) at higher redshift. We argue that
this, and the large fraction of peculiars that appear spiral-like in stellar
mass maps, are possible evidence for either an active bulge formation in some
late-type disks at z<1 or the presence of minor merger events.Comment: 27 pages, MNRAS in pres
Compact High-Redshift Galaxies Are the Cores of the Most Massive Present-Day Spheroids
Observations suggest that effective radii of high-z massive spheroids are as
much as a factor ~6 smaller than low-z galaxies of comparable mass. Given the
apparent absence of low-z counterparts, this has often been interpreted as
indicating that the high density, compact red galaxies must be 'puffed up' by
some mechanism. We compare the ensemble of high-z observations with large
samples of well-observed low-z ellipticals. At the same physical radii, the
stellar surface mass densities of low and high-z systems are comparable.
Moreover, the abundance of high surface density material at low redshift is
comparable to or larger than that observed at z>1-2, consistent with the
continuous buildup of spheroids over this time. The entire population of
compact, high-z red galaxies may be the progenitors of the high-density cores
of present-day ellipticals, with no need for a decrease in stellar density from
z=2 to z=0. The primary difference between low and high-z systems is thus the
observed low-density material at large radii in low-z spheroids (rather than
the high-density material in high-z spheroids). Such low-density material may
either (1) assemble at z2.
Mock observations of low-z massive systems show that the high-z observations do
not yet probe sufficiently low surface brightness material to detect the low
surface density 'wings' (if present). Thus, if the high-z galaxies resemble the
most massive systems today, their inferred effective radii could be
under-estimated by factors ~2-4. This difference arises because massive systems
at low redshift are not well-fit by single Sersic profiles. We discuss
implications of our results for physical models of galaxy evolution.Comment: 14 pages, 6 figures, accepted to MNRAS (revised to match published
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