721 research outputs found
A KINEMATIC COMPARISON OF RUNNING ON TREADMILL AND OVERGROUND SURFACES
Treadmills are often used for research in sport running shoes and physical training. The purpose of this study was to compare the kinematics in treadmill and overground running, and to investigate if the shoe testing on treadmill can reflect the performance of the running shoes on overground surfaces. Thirteen male subjects were recruited to run on treadmill, tartan, grass and concrete surfaces. Effective vertical stiffness, temporal and kinematic parameters were measured. The results showed that the running patterns within overground surfaces were not significantly different, while the significant differences were found between treadmill and overground running
Superheavy dark matter and ultrahigh energy cosmic rays
The phase of inflationary expansion in the early universe produces superheavy
relics in a mass window between 10^{12} GeV and 10^{14} GeV. Decay or
annihilation of these superheavy relics can explain the observed ultrahigh
energy cosmic rays beyond the Greisen-Zatsepin-Kuzmin cutoff. We emphasize that
the pattern of cosmic ray arrival directions with energies beyond 20 EeV will
decide between the different proposals for the origin of ultrahigh energy
cosmic rays.Comment: Based on an invited talk given by RD at Theory Canada 1, Vancouver,
June 2-5, 200
QCD Chiral restoration at finite under the Magnetic field: Studies based on the instanton vacuum model
We investigate the chiral restoration at finite temperature under the
strong external magnetic field of the SU(2) light-flavor
QCD matter. We employ the instanton-liquid QCD vacuum configuration accompanied
with the linear Schwinger method for inducing the magnetic field. The
Harrington-Shepard caloron solution is used to modify the instanton parameters,
i.e. the average instanton size and inter-instanton distance
, as functions of . In addition, we include the meson-loop
corrections (MLC) as the large- corrections because they are critical
for reproducing the universal chiral restoration pattern. We present the
numerical results for the constituent-quark mass as well as chiral condensate
which signal the spontaneous breakdown of chiral-symmetry (SBS), as
functions of and . Besides we find that the changes for the and
due to the magnetic field is relatively small, in comparison to those
caused by the finite effect.Comment: 4 pages, 1 table, 6figs. arXiv admin note: significant text overlap
with arXiv:1103.605
Cultural orientation of self-bias in perceptual matching
This work was supported by grants from the Economic and Social Research Council (ES/K013424/1), the National Natural Science Foundation of China (31371017), and the Research Grants Council of Hong Kong (HKU758412H)Peer reviewedPublisher PD
Theoretical study of the absorption spectra of the sodium dimer
Absorption of radiation from the sodium dimer molecular states correlating to
Na(3s)-Na(3s) is investigated theoretically. Vibrational bound and continuum
transitions from the singlet X Sigma-g+ state to the first excited singlet A
Sigma-u+ and singlet B Pi-u states and from the triplet a Sigma-u+ state to the
first excited triplet b Sigma-g+ and triplet c Pi-g states are studied
quantum-mechanically. Theoretical and experimental data are used to
characterize the molecular properties taking advantage of knowledge recently
obtained from ab initio calculations, spectroscopy, and ultra-cold atom
collision studies. The quantum-mechanical calculations are carried out for
temperatures in the range from 500 to 3000 K and are compared with previous
calculations and measurements where available.Comment: 19 pages, 8 figures, revtex, eps
Defense gene expression and phenotypic changes of rice (Oryza sativa L.) at the reproductive stage in response to whitebacked planthopper (Sogatella furcifera Horvath) infestation
This study was to determine the gene expression pattern and phenotypic change of Cheongcheong, Nagdong, TN1, and 8 different pedigrees of the CNDH population when WBPH infestation initiated at the reproductive stage of the crop. WBPH infested plants generally showed higher expression level of defense genes compared with the uninfected plants. LOX transcriptional levels in Nagdong and CNDH42-1 did not increase after WBPH feeding at all-time course. Chlorophyll content declined in infested plants compared to their controls, but still CNDH3, CNDH14-2, and CNDH65 were healthier. Heavy and extensive WBPH feeding affected rice yield and grain quality although the infestation started at the reproductive stage
Approach to equilibrium for a class of random quantum models of infinite range
We consider random generalizations of a quantum model of infinite range
introduced by Emch and Radin. The generalization allows a neat extension from
the class of absolutely summable lattice potentials to the optimal class
of square summable potentials first considered by Khanin and Sinai and
generalised by van Enter and van Hemmen. The approach to equilibrium in the
case of a Gaussian distribution is proved to be faster than for a Bernoulli
distribution for both short-range and long-range lattice potentials. While
exponential decay to equilibrium is excluded in the nonrandom case, it is
proved to occur for both short and long range potentials for Gaussian
distributions, and for potentials of class in the Bernoulli case. Open
problems are discussed.Comment: 10 pages, no figures. This last version, to appear in J. Stat. Phys.,
corrects some minor errors and includes additional references and comments on
the relation to experiment
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