442 research outputs found
High-Resolution Spectroscopy during Eclipse of the Young Substellar Eclipsing Binary 2MASS 0535-0546. II. Secondary Spectrum: No Evidence that Spots Cause the Temperature Reversal
We present high-resolution optical spectra of the young brown-dwarf eclipsing
binary 2M0535-05, obtained during eclipse of the higher-mass (primary) brown
dwarf. Combined with our previous spectrum of the primary alone (Paper I), the
new observations yield the spectrum of the secondary alone. We investigate,
through a differential analysis of the two binary components, whether cool
surface spots are responsible for suppressing the temperature of the primary.
In Paper I, we found a significant discrepancy between the empirical surface
gravity of the primary and that inferred via fine analysis of its spectrum.
Here we find precisely the same discrepancy in surface gravity, both
qualitatively and quantitatively. While this may again be ascribed to either
cool spots or model opacity errors, it implies that cool spots cannot be
responsible for preferentially lowering the temperature of the primary: if they
were, spot effects on the primary spectrum should be preferentially larger, and
they are not. The Teff we infer for the primary and secondary, from the
TiO-epsilon bands alone, show the same reversal, in the same ratio, as is
empirically observed, bolstering the validity of our analysis. In turn, this
implies that if suppression of convection by magnetic fields on the primary is
the fundamental cause of the Teff reversal, then it cannot be a local
suppression yielding spots mainly on the primary (though both components may be
equally spotted), but a global suppression in the interior of the primary. We
briefly discuss current theories of how this might work.Comment: Final ApJ version. Small textual change in summary at the end (Sec
6.2), to include work published after submission of this paper; no changes in
our results or conclusion
Dimensiones de la asistencia legal. Una propuesta de política pública para el Distrito Federal
La asistencia legal se ha aplicado a personas en situación económica desfavorable, con el fin
de poner a su alcance el litigio y la ayuda profesional de abogados, sobre todo para asuntos relativos al
Derecho penal. Sin embargo, este contexto se ha expandido a otros ámbitos para favorecer a otros usuarios
y para incluir más disciplinas, de modo que se garantice el acceso a la justicia y por ende el debido proceso
legal. Este artículo aborda el tema de la asistencia legal siguiendo su trayectoria y sus implicaciones
políticas en el Estado de bienestar. Se analiza el régimen normativo de la asistencia legal en el Distrito
Federal en el contexto de la Constitución y en comparación con los estándares internacionales, a fin de
redefinir la defensoría de oficio y la asesoría jurídica en el Distrito Federal.Legal assistance has been applied to people in an adverse economic situation, in order to put at
their disposal the professional help of lawyers, especially in matters related to criminal law and litigation.
However, this context has expanded to other areas to help other users and to include more disciplines, so
as to ensure access to justice and therefore due legal process. This paper addresses the issue of legal assistance,
and it traces its trajectory and its political implications in the welfare State. The regulatory regime
of legal assistance in Mexico City is analyzed in the context of the Constitution and in comparison with
international standards, in order to redefine public defense and legal counseling in Mexico City
The Vice of Lust and its Impact on Intellectual Knowledge in the Teachings of Some Fathers of the Church
The question I want to put forth is whether the pleasure that ensues upon lust, regardless it being moderate or excessive, is so strong that it has the power to overwhelm the mind, bringing it into a state that prevents it from approaching reality serenely, and depriving it of clarity and the mental sharpness required to make right decisions and to attain a more accurate understanding of reality. I analyze the question stating as a conclusion that according to John Chrysostom, Gregory of Nyssa, Augustine of Hippo and Gregory the Great, the regulation of sexual desire, which is proper to chastity, anthropologically predisposes the intellect to greater clarity in order to know the truth, whereas lust is unsuitable to attain this knowledge
The Dynamics of Plant Cell Wall In Muro Modifications and its Physiological Implications on Seed Germination
Seed germination is a complex process in which the embryo, enclosed within the surrounding tissues, must quickly switch from a maturation program to a germination‐driven developmental process that will prepare the embryo for seedling growth and establishment. The germination process initiates with water uptake by the dry seed and culminates, usually, with the radicle protrusion. The radicle emergence from the seed is a highly regulated process that involves discrete and coordinated changes in plant cell wall extensibility and rearrangements of its components, among other processes. In this chapter we will review current knowledge of the physiological process of controlled cell separation and expansion, which give the primary cell wall its plastic properties by “loosening” of the main components of the cell wall during seed germination. We will focus on the physiological importance of primary cell wall constitution and modification by the activity in muro of a broad variety of cell wall‐modifying enzymes that include hydrolases and transglycosylases, as well as non‐enzymatic processes such as expansin‐mediated loosening during seed germination
Automated code for the selection of targets to be observed with the SAINT-EX telescope
In this contribution, we present the main characteristics and describe the functioning of the code developed in python language to automatically build the list of objects that are nightly observed in queue mode with the 1-m SAINT-EX telescope.Fil: Petrucci, Romina Paola. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Departamento de Astrofísica Estelar; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gómez Maqueo Chew, Yilen. Instituto de Astronomia; México. Universidad Nacional Autónoma de México; Méxic
Propiedades psicométricas del ASSIST en un grupo de estudiantes mexicanos
Los estudiantes jóvenes son un grupo vulnerable ante el consumo de sustancias: legales
e ilegales. Los instrumentos de detección efi caces son prioritarios para una atención y
canalización oportuna. El objetivo de este trabajo fue obtener la validez concurrente
y la confi abilidad test-retest del ASSIST (Alcohol, Smoking and Substance Involvement
Screening Test). Estudios previos en otros países, han demostrado que el ASSIST posee
validez de constructo, concurrente y discriminativa, así como confi abilidad test-retest
adecuadas. Este instrumento permite clasifi car a los individuos en tres niveles de riesgo
en relación al consumo de sustancias (bajo, moderado y alto). El trabajo se realizó en
dos estudios con una muestra total de 245 jóvenes, reclutados de dos bachilleratos
públicos del Distrito Federal, mediante un muestreo aleatorio simple estratifi cado.
Los instrumentos empleados fueron: ASSIST; AUDIT; Fagerström y el DAST-10. Los
resultados mostraron validez concurrente mediante correlaciones signifi cativas entre
las puntuaciones del ASSIST y las puntuaciones del AUDIT (r=0.50), Fagerström
(r=0.61) y DAST-10 (r=0.30). La prueba presentó estabilidad temporal con coefi cientes
de correlación intraclase (CCI) aceptables y estadísticamente signifi cativos, en un rango
de 0.20 al 0.84. Los hallazgos sugieren que el ASSIST es una prueba válida, confi able
y de aplicación sencilla para la identifi cación y manejo de estudiantes que presentan
consumo riesgo bajo y moderado de sustancias, en escenarios escolares.Young students are vulnerable as regards using legal and illegal drugs. It is important
to conduct studies for developing detection instruments that help health staff with
treatment and derivation. The objective of this paper is to measure concurrent validity
and test-retest reliability of the ASSIST (Alcohol, Smoking and Substance Involvement
Screening Test). Previous studies have shown that the instrument has good construct,
concurrent, and discriminative validity, as well as test-retest reliability. It also classifi es
subjects into three risk levels (low, moderate, and high). The study consisted of two
phases, with a total sample of 245 subjects, randomly selected in two high schools
from Mexico City. A battery of instruments was used: ASSIST, AUDIT, Fagerström, and
DAST-10. Results showed concurrent validity between ASSIST and AUDIT (r=0.50),
Fagerström (r=0.61) and DAST-10 (r=0.30). The ASSIST showed temporal stability (CCI
0.20-0.84). Results suggest that the ASSIST is a valid and reliable instrument, and easy
to use for identifying subjects that have a low and moderate risk of using substances in
school settings
Automated code for the selection of targets to be observed with the SAINT-EX telescope
In this contribution, we present the main characteristics and describe the functioning of the code developed in python language to automatically build the list of objects that are nightly observed in queue mode with the 1-m SAINT-EX telescope.Fil: Petrucci, Romina Paola. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Departamento de Astrofísica Estelar; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gómez Maqueo Chew, Yilen. Instituto de Astronomia; México. Universidad Nacional Autónoma de México; Méxic
A Strict Test of Stellar Evolution Models: The Absolute Dimensions of Massive Benchmark Eclipsing Binary V578 Mon
We determine the absolute dimensions of the eclipsing binary V578 Mon, a
detached system of two early B-type stars (B0V + B1V, P2.40848 d) in the
star-forming region NGC 2244 of the Rosette Nebula. From the light curve
analysis of 40 yr of photometry and the analysis of HERMES spectra, we find
radii of Rsun and Rsun, and temperatures of ~K and K respectively. We find that our
disentangled component spectra for V578 Mon agree well previous spectral
disentangling from the literature. We also reconfirm the previous spectroscopic
orbit of V578 Mon finding that masses of Msun and Msun are fully compatible with the new analysis. We compare the absolute
dimensions to the rotating models of the Geneva and Utrecht groups and the
models of Granada group. We find all three sets of models marginally reproduce
the absolute dimensions of both stars with a common age within uncertainty for
gravity-effective temperature isochrones. However - there are some apparent age
discrepancies for the corresponding mass-radius isochrones. Models with larger
convective overshoot worked best. Combined with our previously
determined apsidal motion of deg cycle,
we compute the internal structure constants (tidal Love number) for the
newtonian and general relativistic contribution to the apsidal motion,
and respectively. We find
the relativistic contribution to the apsidal motion of be small . We find
that the prediction of of the Granada
models fully agrees with our observed .Comment: accepted for publication in AJ 05/02/201
On the Abundance of Circumbinary Planets
We present here the first observationally based determination of the rate of
occurrence of circumbinary planets. This is derived from the publicly available
Kepler data, using an automated search algorithm and debiasing process to
produce occurrence rates implied by the seven systems already known. These
rates depend critically on the planetary inclination distribution: if
circumbinary planets are preferentially coplanar with their host binaries, as
has been suggested, then the rate of occurrence of planets with
orbiting with \ d is \% (95\% confidence limits),
higher than but consistent with single star rates. If on the other hand the
underlying planetary inclination distribution is isotropic, then this
occurrence rate rises dramatically, to give a lower limit of 47\%. This implies
that formation and subsequent dynamical evolution in circumbinary disks must
either lead to largely coplanar planets, or proceed with significantly greater
ease than in circumstellar disks. As a result of this investigation we also
show that giant planets () are significantly less common in
circumbinary orbits than their smaller siblings, and confirm that the proposed
shortfall of circumbinary planets orbiting the shorter period binaries in the
Kepler sample is a real effect.Comment: Accepted for publication in MNRAS (1st August 2014). 12 pages. Update
to match final version, including clarifications and new figures. Results are
unchange
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