7,031 research outputs found
Radiative two-pion decay of the tau lepton
We consider the bremsstrahlung and model-dependent contributions to the
radiative decay in the context of a
meson dominance model. We focus on several observables related to this decay,
including the branching ratio and the photon and di-pion spectra. Particular
attention is paid to the sensitivity of different observables upon the effects
of model-dependent contributions and of the magnetic dipole moment of the
vector meson. Important numerical differences are found with
respect to results obtained in the framework of chiral perturbation theory.Comment: 14 pages, 8 figures, submitted for publicatio
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Capacity of English NHS hospitals to monitor quality in infection prevention and control using a new European framework: a multilevel qualitative analysis
Objective:(1) To assess the extent to which current English national regulations/policies/guidelines and local hospital practices align with indicators suggested by a European review of effective strategies for infection prevention and control (IPC); (2) to examine the capacity of local hospitals to report on the indicators and current use of data to inform IPC management and practice.
Design
A national and local-level analysis of the 27 indicators was conducted. At the national level, documentary review of regulations/policies/guidelines was conducted. At the local level data collection comprised: (a) review of documentary sources from 14 hospitals, to determine the capacity to report performance against these indicators; (b) qualitative interviews with 3 senior managers from 5 hospitals and direct observation of hospital wards to find out if these indicators are used to improve IPC management and practice.
Setting
2 acute English National Health Service (NHS) trusts and 1 NHS foundation trust (14 hospitals).
Participants
3 senior managers from 5 hospitals for qualitative interviews.
Primary and secondary outcome measures
As primary outcome measures, a ‘Red-Amber-Green’ (RAG) rating was developed reflecting how well the indicators were included in national documents or their availability at the local organisational level. The current use of the indicators to inform IPC management and practice was also assessed. The main secondary outcome measure is any inconsistency between national and local RAG rating results.
Results
National regulations/policies/guidelines largely cover the suggested European indicators. The ability of individual hospitals to report some of the indicators at ward level varies across staff groups, which may mask required improvements. A reactive use of staffing-related indicators was observed rather than the suggested prospective strategic approach for IPC management.
Conclusions
For effective patient safety and infection prevention in English hospitals, routine and proactive approaches need to be developed. Our approach to evaluation can be extended to other country settings
The alternative of EXERGAMEs in improving the quality of life of the elderly
Actualmente vivimos en una sociedad claramente condicionada por el alcance de las nuevas tecnologías. Asimismo, el significativo aumento del número de nuestros mayores constituye otra característica que la determina. Esta situación plantea la necesidad de propuestas que promuevan la calidad de vida y bienestar en la tercera edad. Para ello, se ha realizado una revisión bibliográfica considerando el ámbito de la actividad física, el cual se concretada como una de las bazas más importantes a tratar para lograr ese objetivo; y el papel que pueden jugar las nuevas tecnologías en él, concretamente los «Exergames». Por ello, y con el fin de buscar alternativas para la mejora de la salud en la tercera edad, este estudio pretende poner en relieve la utilización de las nuevas tecnologías con dicha meta. En este sentido, se destaca el uso de los videojuegos activos, una tecnología que lleva en auge desde hace algún tiempo, con la cual nuestros mayores podrán no solo mejorar su condición física y mental, sino su calidad de vida de forma global
Two short mass-loss events that unveil the binary heart of Minkowski's Butterfly Nebula
Studying the appearance and properties of bipolar winds is critical to
understand the stellar evolution from the AGB to the planetary nebula (PN)
phase. Many uncertainties exist regarding the presence and role of binary
stellar systems, mainly due to the deficit of conclusive observational
evidences. We investigate the extended equatorial distribution around the early
bipolar planetary nebula M 2-9 ("Minkowski's Butterfly Nebula") to gather new
information on the mechanism of the axial ejections. Interferometric millimeter
observations of molecular emission provide the most comprehensive view of the
equatorial mass distribution and kinematics in early PNe. Here we present
subarcsecond angular-resolution observations of the 12CO J=2-1 line and
continuum emission with the Plateau de Bure interferometer. The data reveal two
ring-shaped and eccentric structures at the equatorial basis of the two coaxial
optical lobes. The two rings were formed during short mass-loss episodes (~ 40
yr), separated by ~ 500 yr. Their positional and dynamical imprints provide
evidence of the presence of a binary stellar system at the center, which yields
critical information on its orbital characteristics, including a mass estimate
for the secondary of ~< 0.2 \ms. The presence of a stellar system with a
modest-mass companion at the center of such an elongated bipolar PN strongly
supports the binary-based models, because these are more easily able to explain
the frequent axisymmetric ejections in PNe.Comment: 8 page
Variables de influencia en la productividad de biomasa de matorral en la mancomunidad de El Alto Jarama-Atazar
La situación energética actual, caracterizada por la búsqueda de nuevas fuentes de energía, sustitutivas de los combustibles fósiles tradicionales y menos agresivas con el medio ambiente, ha hecho necesaria la puesta en marcha de políticas y acuerdos a nivel mundial, que buscan reducir la contaminación y fomentar las energías renovables. La biomasa, recurso renovable perteneciente a cada país y con un poder calorífico suficientemente alto como para emplearse energéticamente, surge como alternativa a dichos combustibles fósiles.
Estos aspectos han convertido el estudio del potencial biomásico de los montes en uno de los pasos previos imprescindibles para cualquier proyecto vinculado al desarrollo de las bioenergías.
Sin embargo, la evaluación de la biomasa encierra numerosas dificultades, dado que como recurso vegetal y renovable que es, presenta un carácter variable, cualitativa y cuantitativamente. Este factor, junto a la complejidad de estimar el potencial biomásico de grandes extensiones, provoca que únicamente se calcule la biomasa arbórea, en detrimento de la arbustiva, proporcionando un valor generalmente más bajo del realmente disponible en cada zona.
Este estudio establece una metodología más precisa para el cálculo de la biomasa potencial generada por el matorral, en una determinada zona de estudio (Mancomunidad de El Alto Jarama-Atazar).____________________________________The present situation in the energy field is mainly characterized by the constant search of new energy sources, traditional fossil fuel substitutive and less aggressive towards the environment. All this has favoured the implementation of policies and worldwide agreements to reduce pollution and to promote Renewable Energies. The Biomass, a renewable resource belonging to each country and with a sufficiently high heating value to use energetically, arises as an alternative to the above mentioned fossil fuels.
These aspects have turned the study of the forestry biomass resources into one of the previous essential steps of any project related to the development of Bioenergy.
However, Biomass quantifying has numerous difficulties given that as vegetable and as renewable resource, it presents a changeable character, both qualitatively and quantitatively. In addition the impossibility to estimate the Biomass potential in large extensions causes that only arboreal biomass to be calculated, to the detriment of the bush tree, and therefore, generally the estimation provides a value that is minor than the real one.
This study tries to establish a more accurate methodology for the calculation of the potential Biomass generated by the thickets in a specific study zone (Mancomunidad de El Alto Jarama-Atazar)
Association of Motivational Climate With Addictive Behaviors Depending on Type of Sport in University Students: Structural Equation Analysis
This research study aims at contrasting a structural model of the associations between the alcohol consumption, tobacco
dependence, and the problematic use of video games with motivational climate toward sport depending on the category of
sports practiced in a sample of Physical Education university students. The sample consisted of 775 university students from
the Autonomous Community of Andalusia (Spain), aged between 21 and 35 (22.22 ± 3.76) years. The instruments used
were the Perceived Motivational Climate in Sport Questionnaire (PMCSQ-2), the Alcohol Use Disorders Identification Test
(AUDIT), the Fagerström Test for Nicotine Dependence (FTND), and the Questionnaire of Experiences Related to Video
Games (QERV) questionnaires. A path model that fitted properly in the multigroup analysis for both categories of sports was
used, χ2 = 19.843; gl = 8; p = .011; comparative fit index (CFI) = 0.911; normed fit index (NFI) = 0.903; incremental fit
index (IFI) = 0.912; root mean square error approximation (RMSEA) = 0.085. An inverse association was shown between
task climate and tobacco consumption in individual sports, being weaker in collective sports. This association is not significant
for collective sports, but it is for individual sports for ego climate. However, a positive association was found between ego
climate and the use of video games in individual sports, not being significant in the case of collective sports. The importance
of promoting motivational climates oriented toward tasks that are based on the practice of collective sports is established,
because they could act as protective factors against the development of addictive behavior in university students.This
research study has been supported by the Education Innovation
Project PID 16-45, named “Implementation of digital resources in
the classroom for the development of psychosocial and motivational
factors in students of the degree in Primary Education with
the speciality in Physical Education,” funded by the University of
Granada. Education Innovation Project PIBD Advanced 470,
named “Program of teaching intervention in students of the degree
in primary education and early childhood education through the use
of new technologies for the improvement of the psychosocial factors
of the students,” funded by the University of Granada. Project
I+D+I “DISPERSA,” with code number TIN2015-67149-C3-R,
named “Design of Pervasive Games Based on Learning Experiences
Sensitive to Context” funded by the Ministry of Economy and
Competitiveness. Precompetitive Research Projects for Young
Researchers (PPJI_B-05); Self-plan Research of the University of
Granada
The effect of personalization on smartphone-based fall detectors
The risk of falling is high among different groups of people, such as older people, individuals with Parkinson''s disease or patients in neuro-rehabilitation units. Developing robust fall detectors is important for acting promptly in case of a fall. Therefore, in this study we propose to personalize smartphone-based detectors to boost their performance as compared to a non-personalized system. Four algorithms were investigated using a public dataset: three novelty detection algorithms—Nearest Neighbor (NN), Local Outlier Factor (LOF) and One-Class Support Vector Machine (OneClass-SVM)—and a traditional supervised algorithm, Support Vector Machine (SVM). The effect of personalization was studied for each subject by considering two different training conditions: data coming only from that subject or data coming from the remaining subjects. The area under the receiver operating characteristic curve (AUC) was selected as the primary figure of merit. The results show that there is a general trend towards the increase in performance by personalizing the detector, but the effect depends on the individual being considered. A personalized NN can reach the performance of a non-personalized SVM (average AUC of 0.9861 and 0.9795, respectively), which is remarkable since NN only uses activities of daily living for training
The disrupted molecular envelope of Frosty Leo
We present maps of CO emission in the protoplanetary nebula Frosty Leo. Observations of the rotational transitions ^(12)CO J=2-1 and 1-0 have been obtained with the IRAM interferometer and the OVRO array. The molecular envelope of Frosty Leo is found to be complex and compact; most of the gas extends ≾6" and shows a structure that is very different to the extended optical nebula. It is composed of a central ring-like structure, whose symmetry axis is inclined ~-40° with respect to the sky plane and expands at speeds of up to ~30 km s^(-1), and high-velocity jets distributed along the symmetry axis of the ring, which reach expansion velocities as high as ~75 km s^(-1). The symmetry axis of the molecular jets in the plane of the sky coincides with the direction of some jet-like features seen in the optical, which are not aligned at all with the main symmetry axis of the optical nebula. The brightness distribution of the ring presents a clumpy structure. We have modeled the spatio-kinematical distribution of, and the excitation conditions in, the molecular envelope. For both transitions, the ^(12)CO emission is found to be very optically thick in the center of the nebula. From our best-fit model, we find that the nebular particle density varies between ~10^5 cm^(-3) and ~10^3 cm^(-3), and that the rotational temperature is very low, ~10 K. The kinematical lifetime of the molecular jets is ~1700 yr, long in comparison with the lifetime of the post-AGB winds of most PPNe. It is very remarkable that the bulk of the gas accelerated during the post-AGB phase of Frosty Leo is located within the central ring, reaching expansion velocities of up to ~30 km s^(-1). The central ring-like distribution of Frosty Leo is probably not the undisrupted remnant of the previous AGB envelope (as found for most PPNe), but its dynamics likely result from multiple post-AGB interactions
Searching for galactic sources in the Swift GRB catalog
Since the early 1990s Gamma Ray Bursts have been accepted to be of
extra-galactic origin due to the isotropic distribution observed by BATSE and
the redshifts observed via absorption line spectroscopy. Nevertheless, upon
further examination at least one case turned out to be of galactic origin. This
particular event presented a Fast Rise, Exponential Decay (FRED) structure
which leads us to believe that other FRED sources might also be Galactic. This
study was set out to estimate the most probable degree of contamination by
galactic sources that certain samples of FREDs have. In order to quantify the
degree of anisotropy the average dipolar and quadripolar moments of each sample
of GRBs with respect to the galactic plane were calculated. This was then
compared to the probability distribution of simulated samples comprised of a
combination of isotropically generated sources and galactic sources. We observe
that the dipolar and quadripolar moments of the selected subsamples of FREDs
are found more than two standard deviations outside those of random
isotropically generated samples.The most probable degree of contamination by
galactic sources for the FRED GRBs of the Swift catalog detected until February
2011 that do not have a known redshift is about 21 out of 77 sources which is
roughly equal to 27%. Furthermore we observe, that by removing from this sample
those bursts that may have any type of indirect redshift indicator and multiple
peaks gives the most probable contamination increases up to 34% (17 out of 49
sources). It is probable that a high degree of contamination by galactic
sources occurs among the single peak FREDs observed by Swift.Comment: Published to A&A, 4 pages, 5 figures, this arXiv version includes
appended table with all the bursts considered in this stud
Minkowski's Footprint revisited. Planetary Nebula formation from a single sudden event?
M1-92 can be considered an archetype of bipolar pre-planetary nebulae. It
shows a clear axial symmetry, along with the kinematics and momentum excess
characteristic of this class of envelopes around post-AGB stars. By taking
advantage of the new extended configuration of the IRAM Plateau de Bure
interferometer, we wanted to study the morphology and velocity field of the
molecular gas better in this nebula, particularly in its central part. We
performed sub-arcsecond resolution interferometric observations of the J=2-1
rotational line 13CO M1-92. We found that the equatorial component is a thin
flat disk, which expands radially with a velocity proportional to the distance
to the center. The kinetic age of this equatorial flow is very similar to that
of the two lobes. The small widths and velocity dispersion in the gas forming
the lobe walls confirm that the acceleration responsible for the nebular shape
could not last more than 100-120 yr. The present kinematics of the molecular
gas can be explained as the result of a single brief acceleration event, after
which the nebula reached an expansion velocity field with axial symmetry. In
view of the similarity to other objects, we speculate on the possibility that
the whole nebula was formed as a result of a magneto-rotational explosion in a
common-envelope system.Comment: 4 pages (2 figures
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