Evaluation of the numeric rating scale for perception of effort during isometric elbow flexion exercise

This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s00421-011-2074-1.The aim of the study was to examine the reliability and validity of the numerical rating scale (0-10 NRS) for rating perception of effort during isometric elbow flexion in healthy people. 33 individuals (32 ± 8 years) participated in the study. Three re-test measurements within one session and three weekly sessions were undertaken to determine the reliability of the scale. The sensitivity of the scale following 10 min isometric fatiguing exercise of the elbow flexors as well as the correlation of the effort with the electromyographic (EMG) activity of the flexor muscles were tested. Perception of effort was tested during isometric elbow flexion at 10, 30, 50, 70, 90, and 100% MVC. The 0-10 NRS demonstrated an excellent test–retest reliability [intra class correlation (ICC) = 0.99 between measurements taken within a session and 0.96 between 3 consecutive weekly sessions]. Exploratory curve fitting for the relationship between effort ratings and voluntary force, and underlying EMG showed that both are best described by power functions (y = ax b ). There were also strong correlations (range 0.89–0.95) between effort ratings and EMG recordings of all flexor muscles supporting the concurrent criterion validity of the measure. The 0-10 NRS was sensitive enough to detect changes in the perceived effort following fatigue and significantly increased at the level of voluntary contraction used in its assessment (p < 0.001). These findings suggest the 0-10 NRS is a valid and reliable scale for rating perception of effort in healthy individuals. Future research should seek to establish the validity of the 0-10 NRS in clinical settings.School of Health Science and Social Care, Brunel Universit

Dynamical Scaling from Multi-Scale Measurements

We present a new measure of the Dynamical Critical behavior: the "Multi-scale Dynamical Exponent (MDE)"Comment: 9 pages,Latex, Request figures from [email protected]

Once more on the Witten index of 3d supersymmetric YM-CS theory

The problem of counting the vacuum states in the supersymmetric 3d Yang-Mills-Chern-Simons theory is reconsidered. We resolve the controversy between its original calculation by Witten at large volumes and the calculation based on the evaluation of the effective Lagrangian in the small volume limit. We show that the latter calculation suffers from uncertainties associated with the singularities in the moduli space of classical vacua where the Born-Oppenheimer approximation breaks down. We also show that these singularities can be accurately treated in the Hamiltonian Born-Oppenheimer method, where one has to match carefully the effective wave functions on the Abelian valley and the wave functions of reduced non-Abelian QM theory near the singularities. This gives the same result as original Witten's calculation.Comment: 27 page

Generation of focusing ion beams by magnetized electron sheath acceleration.

We present the first 3D fully kinetic simulations of laser driven sheath-based ion acceleration with a kilotesla-level applied magnetic field. The application of a strong magnetic field significantly and beneficially alters sheath based ion acceleration and creates two distinct stages in the acceleration process associated with the time-evolving magnetization of the hot electron sheath. The first stage delivers dramatically enhanced acceleration, and the second reverses the typical outward-directed topology of the sheath electric field into a focusing configuration. The net result is a focusing, magnetic field-directed ion source of multiple species with strongly enhanced energy and number. The predicted improvements in ion source characteristics are desirable for applications and suggest a route to experimentally confirm magnetization-related effects in the high energy density regime. We additionally perform a comparison between 2D and 3D simulation geometry, on which basis we predict the feasibility of observing magnetic field effects under experimentally relevant conditions

Application of the DRA method to the calculation of the four-loop QED-type tadpoles

We apply the DRA method to the calculation of the four-loop `QED-type' tadpoles. For arbitrary space-time dimensionality D the results have the form of multiple convergent sums. We use these results to obtain the epsilon-expansion of the integrals around D=3 and D=4.Comment: References added, some typos corrected. Results unchange

The nutrition transition in India

No Abstract.South African Journal of Clinical Nutrition Vol. 18(2) 2005: 198-20

A Posteriori Error Estimates for Nonconforming Approximations of Evolutionary Convection-Diffusion Problems

We derive computable upper bounds for the difference between an exact solution of the evolutionary convection-diffusion problem and an approximation of this solution. The estimates are obtained by certain transformations of the integral identity that defines the generalized solution. These estimates depend on neither special properties of the exact solution nor its approximation, and involve only global constants coming from embedding inequalities. The estimates are first derived for functions in the corresponding energy space, and then possible extensions to classes of piecewise continuous approximations are discussed.Comment: 10 page

Deformations of circle-valued Morse functions on surfaces

Let $M$ be a smooth connected orientable compact surface. Denote by $F(M,S^1)$ the space of all Morse functions $f:M\to S^1$ having no critical points on the boundary of $M$ and such that for every boundary component $V$ of $M$ the restriction $f|_{V}:V\to S^1$ is either a constant map or a covering map. Endow $F(M,S^1)$ with the $C^{\infty}$-topology. In this note the connected components of $F(M,S^1)$ are classified. This result extends the results of S. V. Matveev, V. V. Sharko, and the author for the case of Morse functions being locally constant on the boundary of $M$.Comment: 8 pages, 4 figure

Discrete Convex Functions on Graphs and Their Algorithmic Applications

The present article is an exposition of a theory of discrete convex functions on certain graph structures, developed by the author in recent years. This theory is a spin-off of discrete convex analysis by Murota, and is motivated by combinatorial dualities in multiflow problems and the complexity classification of facility location problems on graphs. We outline the theory and algorithmic applications in combinatorial optimization problems