432 research outputs found
The Persint visualization program for the ATLAS experiment
The Persint program is designed for the three-dimensional representation of
objects and for the interfacing and access to a variety of independent
applications, in a fully interactive way. Facilities are provided for the
spatial navigation and the definition of the visualization properties, in order
to interactively set the viewing and viewed points, and to obtain the desired
perspective. In parallel, applications may be launched through the use of
dedicated interfaces, such as the interactive reconstruction and display of
physics events. Recent developments have focalized on the interfacing to the
XML ATLAS General Detector Description AGDD, making it a widely used tool for
XML developers. The graphics capabilities of this program were exploited in the
context of the ATLAS 2002 Muon Testbeam where it was used as an online event
display, integrated in the online software framework and participating in the
commissioning and debug of the detector system.Comment: 9 pages, 10 figures, proceedings of CHEP200
Evaluating the performance of survey-based operational management procedures
The design and evaluation of survey-based management strategies is addressed in this article, using three case-study fisheries: North Sea herring, Bay of Biscay anchovy and North Sea cod, with a brief history and the main management issues with each fishery outlined. A range of operational management procedures for the case study stocks were designed and evaluated using trends that may be derived from survey indices (spawner biomass, year-class strength and total mortality) with an array of simple and more structured observation error regimes simulated. Model-free and model-based indicators of stock status were employed in the management procedures. On the basis of stochastic stock-specific simulations, we identified the following key determinants of successful management procedures: (i) adequate specification of the stock-recruit relationship (model structure, parameter estimates and variability), (ii) knowledge of the magnitude and structure of the variation in the survey indices, and (iii) explication of the particular management objectives, when assessing management performance. More conservative harvesting strategies are required to meet specified targets in the presence of increasing stochasticity, due to both process and observation error. It was seen that survey-based operational management procedures can perform well in the absence of commercial data, and can also inform aspects of survey design with respect to acceptable levels of error or bias in the surveys
The Arrowhead Mini-Supercluster of Galaxies
Superclusters of galaxies can be defined kinematically from local evaluations
of the velocity shear tensor. The location where the smallest eigenvalue of the
shear is positive and maximal defines the center of a basin of attraction.
Velocity and density fields are reconstructed with Wiener Filter techniques.
Local velocities due to the density field in a restricted region can be
separated from external tidal flows, permitting the identification of
boundaries separating inward flows toward a basin of attraction and outward
flows. This methodology was used to define the Laniakea Supercluster that
includes the Milky Way. Large adjacent structures include Perseus-Pisces, Coma,
Hercules, and Shapley but current kinematic data are insufficient to capture
their full domains. However there is a small region trapped between Laniakea,
Perseus-Pisces, and Coma that is close enough to be reliably characterized and
that satisfies the kinematic definition of a supercluster. Because of its
shape, it is given the name the Arrowhead Supercluster. This entity does not
contain any major clusters. A characteristic dimension is ~25 Mpc and the
contained mass is only ~10^15 Msun.Comment: Accepted for publication in The Astrophysical Journal. Video can be
viewed at http://irfu.cea.fr/arrowhea
Giant disk galaxies : Where environment trumps mass in galaxy evolution
We identify some of the most HI massive and fastest rotating disk galaxies in
the local universe with the aim of probing the processes that drive the
formation of these extreme disk galaxies. By combining data from the Cosmic
Flows project, which has consistently reanalyzed archival galaxy HI profiles,
and 3.6m photometry obtained with the Spitzer Space Telescope, with which
we can measure stellar mass, we use the baryonic Tully-Fisher (BTF)
relationship to explore whether these massive galaxies are distinct. We discuss
several results, but the most striking is the systematic offset of the
HI-massive sample above the BTF. These galaxies have both more gas and more
stars in their disks than the typical disk galaxy of similar rotational
velocity. The "condensed" baryon fraction, , the fraction of the baryons
in a dark matter halo that settle either as cold gas or stars into the disk, is
twice as high in the HI-massive sample than typical, and almost reaches the
universal baryon fraction in some cases, suggesting that the most extreme of
these galaxies have little in the way of a hot baryonic component or cold
baryons distributed well outside the disk. In contrast, the star formation
efficiency, measured as the ratio of the mass in stars to that in both stars
and gas, shows no difference between the HI-massive sample and the typical disk
galaxies. We conclude that the star formation efficiency is driven by an
internal, self-regulating process, while is affected by external factors.
We also found that the most massive HI detected galaxies are located
preferentially in filaments. We present the first evidence of an environmental
effect on galaxy evolution using a dynamical definition of a filament.Comment: 14 pages, in press MNRA
Planes of satellite galaxies and the cosmic web
Recent observational studies have demonstrated that the majority of satellite
galaxies tend to orbit their hosts on highly flattened, vast, possibly
co-rotating planes. Two nearly parallel planes of satellites have been
confirmed around the M31 galaxy and around the Centaurus A galaxy, while the
Milky Way also sports a plane of satellites. It has been argued that such an
alignment of satellites on vast planes is unexpected in the standard
({\Lambda}CDM) model of cosmology if not even in contradiction to its generic
predictions. Guided by {\Lambda}CDM numerical simulations, which suggest that
satellites are channeled towards hosts along the axis of the slowest collapse
as dictated by the ambient velocity shear tensor, we re-examine the planes of
local satellites systems within the framework of the local shear tensor derived
from the Cosmicflows-2 dataset. The analysis reveals that the Local Group and
Centaurus A reside in a filament stretched by the Virgo cluster and compressed
by the expansion of the Local Void. Four out of five thin planes of satellite
galaxies are indeed closely aligned with the axis of compression induced by the
Local Void. Being the less massive system, the moderate misalignment of the
Milky Way's satellite plane can likely be ascribed to its greater
susceptibility to tidal torques, as suggested by numerical simulations. The
alignment of satellite systems in the local universe with the ambient shear
field is thus in general agreement with predictions of the {\Lambda}CDM model.Comment: 9 pages, 3 figures, 3 tables. Accepted by MNRAS, 9 June 201
WALLABY Pre-Pilot Survey: H I Content of the Eridanus Supergroup
We present observations of the Eridanus supergroup obtained with the Australian Square Kilometre Array Pathfinder (ASKAP) as part of the pre-pilot survey for the Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY). The total number of detected H I sources is 55, of which 12 are background galaxies not associated with the Eridanus supergroup. Two massive H I clouds are identified and large H I debris fields are seen in the NGC 1359 interacting galaxy pair, and the face-on spiral galaxy NGC 1385. We describe the data products from the source finding algorithm and present the basic parameters. The presence of distorted H I morphology in all detected galaxies suggests ongoing tidal interactions within the subgroups. The Eridanus group has a large fraction of H I deficient galaxies as compared to previously studied galaxy groups. These H I deficient galaxies are not found at the centre of the group. We find that galaxies in the Eridanus supergroup do not follow the general trend of the atomic gas fraction versus stellar mass scaling relation, which indicates that the scaling relation changes with environmental density. In general, the majority of these galaxies are actively forming stars
Clinical Simulation in Nursing Community
Podeu consultar la Vuitena trobada de professorat de Ciències de la Salut completa a: http://hdl.handle.net/2445/66524La finalidad de esta investigación fue evaluar los resultados de aprendizaje del
alumno en relación a las competencias en enfermería comunitaria y valorar la
satisfacción de los mismos respecto a la simulación clínica en este contexto.
Material y métodos: Estudio descriptivo observacional realizado en el primer
semestre del curso 2014/2015 en el Campus Docent Sant Joan de Déu.
Se hizo un análisis cualitativo de la conducción de 30 debriefings donde se
evaluaron los resultados de aprendizaje en relación a los siguientes ítems
(aspectos emocionales, toma de decisiones, valoración integral del paciente,
valoración del paciente en atención domiciliaria, comunicación, educación
sanitaria y habilidades técnicas).
La satisfacción de los estudiantes se evaluó mediante un cuestionario
compuesto por 8 ítems valorados mediante una escala ordinal (contenidos,
coordinación, tiempo, metodología, utilidad, material, conocimientos,
expectativas) y se realizó un análisis descriptivo de cada uno de ellos.
Resultados: El análisis de los debriefings mostró que los alumnos tienen
dificultades para realizar la valoración del paciente con los instrumentos que se
utilizan en la práctica clínica, sin embargo presentan buenas habilidades
comunicativas con el usuario y la familia. Respecto el grado de satisfacción,
participaron en la cumplimentación del cuestionario, 47 estudiantes de tercer
curso de Grado, la puntuación media total de los alumnos fue de 9,08 (DE
0,85). La utilidad del taller fue valorada con una media superior a 9.
Conclusiones: La simulación clínica es una metodología docente valorada
satisfactoriamente por parte de los alumnos, que permite trabajar objetivos
relacionados con habilidades técnicas y con habilidades no técnicas
Simulación clínica en enfermería comunitaria
Introducción: La finalidad de esta investigación fue evaluar los resultados de aprendizaje del alumno en relación a las competencias en enfermería comunitaria y valorar la satisfacción de los mismos respecto a la simulación clínica en este contexto. Material y métodos: Estudio descriptivo observacional realizado en el primer semestre del curso 2014/2015 en el Campus Docent Sant Joan de Déu. Se hizo un análisis cualitativo de la conducción de 30 debriefings donde se evaluaron los resultados de aprendizaje en relación a los siguientes ítems (aspectos emocionales, toma de decisiones, valoración integral del paciente, valoración del paciente en atención domiciliaria, comunicación, educación sanitaria y habilidades técnicas). La satisfacción de los estudiantes se evaluó mediante un cuestionario compuesto por 8 ítems valorados mediante una escala ordinal (contenidos, coordinación, tiempo, metodología, utilidad, material, conocimientos, expectativas) y se realizó un análisis descriptivo de cada uno de ellos. Resultados: El análisis de los debriefings mostró que los alumnos tienen dificultades para realizar la valoración del paciente con los instrumentos que se utilizan en la práctica clínica, sin embargo presentan buenas habilidades comunicativas con el usuario y la familia. Respecto el grado de satisfacción, participaron en la cumplimentación del cuestionario, 47 estudiantes de tercer curso de Grado, la puntuación media total de los alumnos fue de 9,08 (DE 0,85). La utilidad del taller fue valorada con una media superior a 9. Conclusiones: La simulación clínica es una metodología docente valorada satisfactoriamente por parte de los alumnos, que permite trabajar objetivos relacionados con habilidades técnicas y con habilidades no técnicas. Palabras clave: simulación clínica, enfermería comunitaria, simulación con actores, habilidades no técnicas
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