10,631 research outputs found
Gait parameter changes during 10000 metre treadmill running
The purpose of this study was to measure the effects of fatigue on gait parameters during running. Research has shown that changes due to fatigue include those of step length, cadence, flight time, and joint angles. Thirteen male distance runners ran 10000 m at a pace equivalent to 103% of their personal best time. Kinetic data was collected using a Gaitway treadmill (1000 Hz), and kinematic data using two RedLake MotionPro high-speed cameras (250 Hz). Data was collected at five points. Repeated measures ANOVA showed that there were significant differences in maximum force, impulse, and contact time (p < .01). Dependent t-tests showed a significant difference for the knee angle at take-off (p < .01). The kinetic and temporal changes occurred as early as 3000 m. Athletes are recommended to race at a constant pace to reduce the effects of fatigue
Probing the spin-parity of the Higgs boson via jet kinematics in vector boson fusion
Determining the spin and the parity quantum numbers of the recently
discovered Higgs-like boson at the LHC is a matter of great importance. In this
paper, we consider the possibility of using the kinematics of the tagging jets
in Higgs production via the vector boson fusion (VBF) process to test the
tensor structure of the Higgs-vector boson () interaction and to determine
the spin and CP properties of the observed resonance. We show that an anomalous
vertex, in particular its explicit momentum dependence, drastically
affects the rapidity between the two scattered quarks and their transverse
momenta and, hence, the acceptance of the kinematical cuts that allow to select
the VBF topology. The sensitivity of these observables to different spin-parity
assignments, including the dependence on the LHC center of mass energy, are
evaluated. In addition, we show that in associated Higgs production with a
vector boson some kinematical variables, such as the invariant mass of the
system and the transverse momenta of the two bosons and their separation in
rapidity, are also sensitive to the spin--parity assignments of the Higgs--like
boson.Comment: 15 pages, 5 figure
On Thermal-Pulse-Driven Plasma Flows in Coronal Funnels as Observed by Hinode/EUV Imaging Spectrometer (EIS)
Using one-arcsecond-slit scan observations from the Hinode/EUV Imaging
Spectrometer (EIS) on 05 February 2007, we find the plasma outflows in the open
and expanding coronal funnels at the eastern boundary of AR 10940. The Doppler
velocity map of Fe XII 195.120 A shows that the diffuse close-loop system to be
mostly red-shifted. The open arches (funnels) at the eastern boundary of AR
exhibit blue-shifts with a maximum speed of about 10-15 km/s. This implies
outflowing plasma through these magnetic structures. In support of these
observations, we perform a 2D numerical simulation of the expanding coronal
funnels by solving the set of ideal MHD equations in appropriate VAL-III C
initial temperature conditions using the FLASH code. We implement a rarefied
and hotter region at the footpoint of the model funnel, which results in the
evolution of slow plasma perturbations propagating outward in the form of
plasma flows. We conclude that the heating, which may result from magnetic
reconnection, can trigger the observed plasma outflows in such coronal funnels.
This can transport mass into the higher corona, giving rise to the formation of
the nascent solar wind.Comment: 17 Pages; 7 Figure
Exploration of the Genetic Epidemiology of Asthma: A Review, With a Focus on Prevalence in Children and Adolescents in the Caribbean
Asthma is a chronic disease caused by the inflammation of the main air passages of the lungs. This paper outlines a review of the published literature on asthma. While a few studies show a trend of rising asthma cases in the Caribbean region, even fewer have explored the genetic epidemiological factors of asthma. This is a literature review that seeks to sum the body of knowledge on the epidemiology of asthma. Specifically, the major objective of the literature review is to provide a unified information base on the current state of factors involved in the genetic epidemiology of asthma. The review is a simple, yet detailed summary of the literature sources and their methodology and findings on the genetic epidemiology of asthma. Further, it seeks to direct this effort to the Caribbean region. The paper then reviews a summarized and synthesized collection of the body of previous research. Of specific interest are peer-reviewed sources that have been published in recent times. The paper provides more recent insight and recapitulates on the previous research, while tracing the intellectual progress on the debate. Where possible, reviewing and discussing the results of the previous literature, this review singles out the gaps and potential future research directions for studying the genetic epidemiology of asthma. Overall, we hope to contribute to a more synthesized knowledge and improved understanding of the previous literature and future potential direction of genetic and epidemiological asthma research
GRB000301C with peculiar afterglow emission
The CCD magnitudes in Johnson V and Cousins R and I photometric passbands are
determined for GRB 000301C afterglow starting ~ 1.5 day after the gamma-ray
burst. In fact we provide the earliest optical observations for this burst.
Light curves of the afterglow emissions in U, B, V, R, I, J and K' passbands
are obtained by combining the present measurements with the published data.
Flux decay shows a very uncommon variation relative to other well observed
GRBs. Overall, there is a steepening of the optical and near-infrared flux
decay caused by a geometric and sideways expanding jet. This is superimposed by
a short term variability especially during early time (Delta t < 8 days). The
cause of variability is not well understood, though it has occurred
simultaneously with similar amplitude in all the filters. We derive the early
and late time flux decay constants using jet model. The late time flux decay is
the steepest amongst the GRB OTs observed so far with alpha ~ 3. Steepening in
the flux decay seems to have started simultaneously around Delta t ~ 7.6 day in
all passbands. The value of spectral index in the optical-near IR region is ~
-1.0. Redshift determination with z=2.0335 indicates cosmological origin of the
GRB having a luminosity distance of 16.6 Gpc. Thus it becomes the second
farthest amongst the GRBs with known distances. An indirect estimate of the
fluence > 20 keV indicates, if isotropic,> =10^53 ergs of release of energy.
The enormous amount of released energy will be reduced, if the radiation is
beamed which is the case for this event. Using a jet break time of 7.6 days, we
infer a jet opening angle of ~ 0.15 radian. This means the energy released is
reduced by a factor of ~ 90 relative to the isotropic value.Comment: LaTeX file, 11 pages including 4 figures, uses psfig.sty, Bull.
Astron. Society of India(accepted, Sept, 2000 issue
Quantum non-demolition measurements of single donor spins in semiconductors
We propose a technique for measuring the state of a single donor electron
spin using a field-effect transistor induced two-dimensional electron gas and
electrically detected magnetic resonance techniques. The scheme is facilitated
by hyperfine coupling to the donor nucleus. We analyze the potential
sensitivity and outline experimental requirements. Our measurement provides a
single-shot, projective, and quantum non-demolition measurement of an
electron-encoded qubit state.Comment: 8+ pages. 4 figures. Published versio
Design of Static Segment Adder for Approximating Computing Applications
The digital VLSI design needs to attain high performance with desired reliability range. The high performance involves low power, area efficiency and high speed. This paper proposes a design of High speed energy efficient static segment adder (SSA) to enhance the overall performance based on approximation technique. Static segmentation includes both accurate and inaccurate part. The normal full adder performs accurate part and the carry select adder is used for inaccurate part. By using static segmentation the approximate computation is done. Approximate computing is a computation which generates “good enough” result rather than totally accurate result. Image processing is accomplished using SSA design. In this process 99.4% whole computational accuracy for 16 bit addition and also for 8 bit addition can be achieved
Numerical Study of the Lowest Energy Configurations for Global String-Antistring Pairs
We investigate the lowest energy configurations for string - antistring pairs
at fixed separations by numerically minimizing the energy. We show that for
separations smaller than a critical value, a region of false vacuum develops in
the middle due to large gradient energy density. Consequently, well defined
string - antistring pairs do not exist for such separations. We present an
example of vortex - antivortex production by vacuum bubbles where this effect
seems to play a dynamical role in the annihilation of the pair. We also study
the dependence of the energy of an string-antistring pair on their separation
and find deviations from a simple logarithmic dependence for small separations.Comment: 14 pages, in LATEX, 7 figures (not included
STUDY ON PREVALENCE OF DEPRESSION AND ADVERSE DRUG REACTIONS AMONG SOUTH INDIAN EPILEPTIC PATIENTS
Objectives: To compare the prevalence and intensity of adverse drug reactions (ADR) in patients receiving antiepileptic monotherapy and polytherapy,and to assess the pattern of depression associated with the therapy.Methods: This is a prospective observational study conducted in neurology outpatient department for a time period of 6 months in a tertiary carehospital, South India. Patients diagnosed as epileptic for more than 6 months and receiving stable doses of antiepileptic drugs (AED) for 3 monthswere included in the study. Study participants receiving monotherapy and polytherapy were divided into groups. A detailed validated questionnairewas used to assess the incidence and severity of depression and ADRs among the study participants. Mann–Whitney test, Kruskal–Wallis test, andWilcoxon signed rank test were used to know the statistical significance at p<0.05.Results: Among 91 patients with epilepsy, depression was observed mainly in the study group receiving polytherapy than monotherapy. The severityof ADR observed among various study groups during the first and second visit were compared, which showed that all range of intensity scores werereported. During the second visit, the severity of ADR was high when compared to the first visit. Further incidence of ADRs with AED therapy wascompared which showed clinically significant values in all ADRs reported in both monotherapy and polytherapy.Conclusion: Our study showed, maximum ADRs were among the patients receiving polytherapy, and depression was observed in patients receivingpolytherapy. This suggests the need for safe drug practice.Keywords: Epilepsy, Anti-epileptics, Adverse drug reactions, Depression, Monotherapy, Polytherapy.Â
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