1,056 research outputs found
Recreational soccer is an effective health-promoting activity for untrained men
Copyright BMJ publishing GroupTo examine the effects of regular participation in recreational soccer on health profile, 36 healthy untrained Danish men aged 20-43 years were randomised into a soccer group (SO; n=13), a running group (RU; n=12) and a control group (CO; n=11). Training was performed for 1 h two or three times per week for 12 weeks; at an average heart rate of 82% (SEM 2%) and 82% (1%) of HRmax for SO and RU, respectively. During the 12 week period, maximal oxygen uptake increased (p < 0.05) by 13% (3%) and 8% (3%) in SO and RU, respectively. In SO, systolic and diastolic blood pressure were reduced (p < 0.05) from 130 (2) to 122 (2) mm Hg and from 77 (2) to 72 (2) mm Hg, respectively, after 12 weeks, with similar decreases observed for RU. After the 12 weeks of training, fat mass was 3.0% (2.7 (0.6) kg) and 1.8% (1.8 (0.4) kg) lower (p < 0.05) for SO and RU, respectively. Only SO had an increase in lean body mass (1.7 (0.4) kg, p < 0.05), an increase in lower extremity bone mass (41 (8) g, p < 0.05), a decrease in LDL-cholesterol (2.7 (0.2) to 2.3 (0.2) mmol/l; p < 0.05) and an increase (p < 0.05) in fat oxidation during running at 9.5 km/h. The number of capillaries per muscle fibre was 23% (4%) and 16% (7%) higher (p < 0.05) in SO and RU, respectively, after 12 weeks. No changes in any of the measured variables were observed for CO. In conclusion, participation in regular recreational soccer training, organised as small-sided drills, has significant beneficial effects on health profile and physical capacity for untrained men, and in some aspects it is superior to frequent moderate-intensity running
Eigentheory of Cayley-Dickson algebras
We show how eigentheory clarifies many algebraic properties of Cayley-Dickson
algebras. These notes are intended as background material for those who are
studying this eigentheory more closely.Comment: 17 page
Interactions between magnetohydrodynamic shear instabilities and convective flows in the solar interior
Motivated by the interface model for the solar dynamo, this paper explores
the complex magnetohydrodynamic interactions between convective flows and
shear-driven instabilities. Initially, we consider the dynamics of a forced
shear flow across a convectively-stable polytropic layer, in the presence of a
vertical magnetic field. When the imposed magnetic field is weak, the dynamics
are dominated by a shear flow (Kelvin-Helmholtz type) instability. For stronger
fields, a magnetic buoyancy instability is preferred. If this stably stratified
shear layer lies below a convectively unstable region, these two regions can
interact. Once again, when the imposed field is very weak, the dynamical
effects of the magnetic field are negligible and the interactions between the
shear layer and the convective layer are relatively minor. However, if the
magnetic field is strong enough to favour magnetic buoyancy instabilities in
the shear layer, extended magnetic flux concentrations form and rise into the
convective layer. These magnetic structures have a highly disruptive effect
upon the convective motions in the upper layer.Comment: 11 pages, 10 figures, accepted for publication in MNRA
Logarithmic Corrections to Schwarzschild and Other Non-extremal Black Hole Entropy in Different Dimensions
Euclidean gravity method has been successful in computing logarithmic
corrections to extremal black hole entropy in terms of low energy data, and
gives results in perfect agreement with the microscopic results in string
theory. Motivated by this success we apply Euclidean gravity to compute
logarithmic corrections to the entropy of various non-extremal black holes in
different dimensions, taking special care of integration over the zero modes
and keeping track of the ensemble in which the computation is done. These
results provide strong constraint on any ultraviolet completion of the theory
if the latter is able to give an independent computation of the entropy of
non-extremal black holes from microscopic description. For Schwarzschild black
holes in four space-time dimensions the macroscopic result seems to disagree
with the existing result in loop quantum gravity.Comment: LaTeX, 40 pages; corrected small typos and added reference
Proportionate vs disproportionate distribution of wealth of two individuals in a tempered Paretian ensemble
We study the distribution P(\omega) of the random variable \omega = x_1/(x_1
+ x_2), where x_1 and x_2 are the wealths of two individuals selected at random
from the same tempered Paretian ensemble characterized by the distribution
\Psi(x) \sim \phi(x)/x^{1 + \alpha}, where \alpha > 0 is the Pareto index and
is the cut-off function. We consider two forms of \phi(x): a bounded
function \phi(x) = 1 for L \leq x \leq H, and zero otherwise, and a smooth
exponential function \phi(x) = \exp(-L/x - x/H). In both cases \Psi(x) has
moments of arbitrary order.
We show that, for \alpha > 1, P(\omega) always has a unimodal form and is
peaked at \omega = 1/2, so that most probably x_1 \approx x_2. For 0 < \alpha <
1 we observe a more complicated behavior which depends on the value of \delta =
L/H. In particular, for \delta < \delta_c - a certain threshold value -
P(\omega) has a three-modal (for a bounded \phi(x)) and a bimodal M-shape (for
an exponential \phi(x)) form which signifies that in such ensembles the wealths
x_1 and x_2 are disproportionately different.Comment: 9 pages, 8 figures, to appear in Physica
Scandinavian Flagship Universities: an Appraisal of Leading National Universities in the European Context
In the immediate post-Sputnik era, Clark Kerr saw America’s breed of universities as “multiversities,” characterized by growing enrollment, an increasingly diversified academic community, and as the emerging driver of knowledge production and innovation (Kerr 2001: xi). This is now a widely shared vision throughout the world. Governments have provided additional funding, fueling further growth in academic programs and attracting talent. One result: the number of perceived stakeholders has increased, along with their expectations
Logarithmic Corrections to Extremal Black Hole Entropy from Quantum Entropy Function
We evaluate the one loop determinant of matter multiplet fields of N=4
supergravity in the near horizon geometry of quarter BPS black holes, and use
it to calculate logarithmic corrections to the entropy of these black holes
using the quantum entropy function formalism. We show that even though
individual fields give non-vanishing logarithmic contribution to the entropy,
the net contribution from all the fields in the matter multiplet vanishes. Thus
logarithmic corrections to the entropy of quarter BPS black holes, if present,
must be independent of the number of matter multiplet fields in the theory.
This is consistent with the microscopic results. During our analysis we also
determine the complete spectrum of small fluctuations of matter multiplet
fields in the near horizon geometry.Comment: LaTeX file, 52 pages; v2: minor corrections, references adde
Border Terriers under primary veterinary care in England: demography and disorders
The Border Terrier is a working terrier type that is generally considered to be a relatively healthy and hardy breed. This study aimed to characterise the demography and common disorders of Border Terriers receiving veterinary care in England using de-identified electronic patient record data within the VetCompass™ Programme
Techniques for temporal detection of neural sensitivity to external stimulation
We propose a simple measure of neural sensitivity for characterizing stimulus coding. Sensitivity is defined as the fraction of neurons that show positive responses to n stimuli out of a total of N. To determine a positive response, we propose two methods: Fisherian statistical testing and a data-driven Bayesian approach to determine the response probability of a neuron. The latter is non-parametric, data-driven, and captures a lower bound for the probability of neural responses to sensory stimulation. Both methods are compared with a standard test that assumes normal probability distributions. We applied the sensitivity estimation based on the proposed method to experimental data recorded from the mushroom body (MB) of locusts. We show that there is a broad range of sensitivity that the MB response sweeps during odor stimulation. The neurons are initially tuned to specific odors, but tend to demonstrate a generalist behavior towards the end of the stimulus period, meaning that the emphasis shifts from discrimination to feature learning
Normalizing acronyms and abbreviations to aid patient understanding of clinical texts: ShARe/CLEF eHealth Challenge 2013, Task 2
Background: The ShARe/CLEF eHealth challenge lab aims to stimulate development of natural language
processing and information retrieval technologies to aid patients in understanding their clinical reports. In clinical
text, acronyms and abbreviations, also referenced as short forms, can be difficult for patients to understand. For one
of three shared tasks in 2013 (Task 2), we generated a reference standard of clinical short forms normalized to the
Unified Medical Language System. This reference standard can be used to improve patient understanding by
linking to web sources with lay descriptions of annotated short forms or by substituting short forms with a more
simplified, lay term.
Methods: In this study, we evaluate 1) accuracy of participating systems’ normalizing short forms compared to a
majority sense baseline approach, 2) performance of participants’ systems for short forms with variable majority
sense distributions, and 3) report the accuracy of participating systems’ normalizing shared normalized concepts
between the test set and the Consumer Health Vocabulary, a vocabulary of lay medical terms.
Results: The best systems submitted by the five participating teams performed with accuracies ranging from 43 to
72 %. A majority sense baseline approach achieved the second best performance. The performance of participating
systems for normalizing short forms with two or more senses with low ambiguity (majority sense greater than
80 %) ranged from 52 to 78 % accuracy, with two or more senses with moderate ambiguity (majority sense
between 50 and 80 %) ranged from 23 to 57 % accuracy, and with two or more senses with high ambiguity
(majority sense less than 50 %) ranged from 2 to 45 % accuracy. With respect to the ShARe test set, 69 % of short
form annotations contained common concept unique identifiers with the Consumer Health Vocabulary. For these
2594 possible annotations, the performance of participating systems ranged from 50 to 75 % accuracy.
Conclusion: Short form normalization continues to be a challenging problem. Short form normalization systems
perform with moderate to reasonable accuracies. The Consumer Health Vocabulary could enrich its knowledge base
with missed concept unique identifiers from the ShARe test set to further support patient understanding of
unfamiliar medical terms.</p
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