945 research outputs found
Evaluation of Body Composition and Somatotype Characteristics of Male
In an effort to describe the physique and body composition associated with performance of University level male track and field athlete of India, this study was conducted on 93 track and field athletes from South India, comprised of 22 sprinters (100 and 200 mts), mean age 19.5 years, height 172.1cm and weight 68.2 kg, 20 middle distance runners (800 and 1500 mts), mean age 19 years, height 166.8cm and weight 62.5 kg, 16 long distance runners (5000 and 10000 mts), mean age 18.7 years, height 167.2cm and weight 62.1kg, 20 throwers, (shot, discus and hammer throw), mean age 19 years, height 170.8cm and weight 72.6 kg and Jumpers (High, long and triple jump), mean age 18.3 years, height 169.9cm, weight 64.1kg. Besides height and weight, six skinfolds (triceps, chest, subscapular, abdomen, suprailiac and calf), two bicondylar breadths (humerus and femur) and two girths (biceps and calf) were measured. Somatotype evaluations were made according to Heath & Carter method. Percent body fat was assessed using equation prescribed by Berzerk et al. (1963). BMI was calculated as body mass divided by square of height (kg/m2). The somatochart indicated that sprinters and middle distance runners are ectomorphic mesomorphs, long distance runners are mesomorph ectomorphs while throwers are endomorphic mesomorphs. The jumpers fell into the somatotype category of balanced mesomorphs. Among all groups body fat percentage is lowest in sprinters (6.23±.83%) and highest in throwers (7.38±.85%). This was reflected in their endomorphic components which is lowest in sprinters (2.53±.0.45) and highest in throwers (3.39±0.65). Ectomorphic component is highly marked in long distance runners (3.56±0.65) while mesomophy was highest in sprinters (4.31±0.91). Throwers have significantly higher values of skinfolds than other groups. Compared to their overseas counterparts, the athletes of both track and field events in the present study exhibited greater endomorphic values. The present data will serve as a reference standard for the anthropometry and body composition of Indian track and field athletes. Â
Differential induction of chitinase in Piper colubrinum in response to inoculation with Phytophthora capsici, the cause of foot rot in black pepper
AbstractPlant chitinases have been of particular interest since they are known to be induced upon pathogen invasion. Inoculation of Piper colubrinum leaves with the foot rot fungus, Phytophthora capsici leads to increase in chitinase activity. A marked increase in chitinase activity in the inoculated leaves was observed, with the maximum activity after 60h of inoculation and gradually decreased thereafter. Older leaves showed more chitinase activity than young leaves. The level of chitinase in black pepper (Piper nigrum L.) upon inoculation was found to be substantially high when compared to P. colubrinum. RT–PCR using chitinase specific primers revealed differential accumulation of mRNA in P. colubrinum leaves inoculated with P. capsici. However, hyphal extension assays revealed no obvious differences in the ability of the protein extracts to inhibit growth of P. capsici in vitro
Double-Logarithmic Two-Loop Self-Energy Corrections to the Lamb Shift
Self-energy corrections involving logarithms of the parameter Zalpha can
often be derived within a simplified approach, avoiding calculational
difficulties typical of the problematic non-logarithmic corrections (as
customary in bound-state quantum electrodynamics, we denote by Z the nuclear
charge number, and by alpha the fine-structure constant). For some logarithmic
corrections, it is sufficient to consider internal properties of the electron
characterized by form factors. We provide a detailed derivation of related
self-energy ``potentials'' that give rise to the logarithmic corrections; these
potentials are local in coordinate space. We focus on the double-logarithmic
two-loop coefficient B_62 for P states and states with higher angular momenta
in hydrogenlike systems. We complement the discussion by a systematic
derivation of B_62 based on nonrelativistic quantum electrodynamics (NRQED). In
particular, we find that an additional double logarithm generated by the
loop-after-loop diagram cancels when the entire gauge-invariant set of two-loop
self-energy diagrams is considered. This double logarithm is not contained in
the effective-potential approach.Comment: 14 pages, 1 figure; references added and typographical errors
corrected; to appear in Phys. Rev.
Extra-dimensional cosmology with domain-wall branes
We show how to define a consistent braneworld cosmology in a model in which
the brane is constructed as a field-theoretic domain wall of finite thickness.
The Friedmann, Robertson-Walker metric is recovered in the region of the brane,
but, remarkably, with scale factor that depends on particle energy and on
particle species, constituting a breakdown of the weak equivalence principle on
sufficiently small scales. This unusual effect comes from the extended nature
of particles confined to a domain-wall brane, and the fact that they feel an
"average" of the bulk spacetime. We demonstrate how to recover the standard
results of brane cosmology in the infinitely-thin brane limit, and comment on
how our results have the potential to place bounds on parameters such as the
thickness of domain-wall braneworlds.Comment: 23 pages; v2 has additional references and reflects journal versio
A first-principles study of oxygen vacancy pinning of domain walls in PbTiO3
We have investigated the interaction of oxygen vacancies and 180-degree
domain walls in tetragonal PbTiO3 using density-functional theory. Our
calculations indicate that the vacancies do have a lower formation energy in
the domain wall than in the bulk, thereby confirming the tendency of these
defects to migrate to, and pin, the domain walls. The pinning energies are
reported for each of the three possible orientations of the original Ti-O-Ti
bonds, and attempts to model the results with simple continuum models are
discussed.Comment: 8 pages, with 3 postscript figures embedded. Uses REVTEX and epsf
macros. Also available at
http://www.physics.rutgers.edu/~dhv/preprints/lh_dw/index.htm
Energy Flow in Interjet Radiation
We study the distribution of transverse energy, Q_Omega, radiated into an
arbitrary interjet angular region, Omega, in high-p_T two-jet events. Using an
approximation that emphasizes radiation directly from the partons that undergo
the hard scattering, we find a distribution that can be extrapolated smoothly
to Q_Omega=Lambda_QCD, where it vanishes. This method, which we apply
numerically in a valence quark approximation, provides a class of predictions
on transverse energy radiated between jets, as a function of jet energy and
rapidity, and of the choice of the region Omega in which the energy is
measured. We discuss the relation of our approximation to the radiation from
unobserved partons of intermediate energy, whose importance was identified by
Dasgupta and Salam.Comment: 26 pages, 8 eps figures. Revised to include a discussion of
non-global logarithm
Disruption of the murine major vault protein (MVP/LRP) gene does not induce hypersensitivity to cytostatics
Vaults are ribonucleoprotein particles with a distinct structure and a
high degree of conservation between species. Although no function has been
assigned to the complex yet, there is some evidence for a role of vaults
in multidrug resistance. To confirm a direct relation between vaults and
multidrug resistance, and to investigate other possible functions of
vaults, we have generated a major vault protein (MVP/lung
resistance-related protein) knockout mouse model. The MVP(-/-) mice are
viable, healthy, and show no obvious abnormalities. We investigated the
sensitivity of MVP(-/-) embryonic stem cells and bone marrow cells derived
from the MVP-deficient mice to various cytostatic agents with different
mechanisms of action. Neither the MVP(-/-) embryonic stem cells nor the
MVP(-/-) bone marrow cells showed an increased sensitivity to any of the
drugs examined, as compared with wild-type cells. Furthermore, the
activities of the ABC-transporters P-glycoprotein, multidrug
resistance-associated protein and breast cancer resistance protein were
unaltered on MVP deletion in these cells. In addition, MVP wild-type and
deficient mice were treated with the anthracycline doxorubicin. Both
groups of mice responded similarly to the doxorubicin treatment. Our
results suggest that MVP/vaults are not directly involved in the
resistance to cytostatic agents
One-loop corrections to the metastable vacuum decay
We evaluate the one-loop prefactor in the false vacuum decay rate in a theory
of a self interacting scalar field in 3+1 dimensions. We use a numerical
method, established some time ago, which is based on a well-known theorem on
functional determinants. The proper handling of zero modes and of
renormalization is discussed. The numerical results in particular show that
quantum corrections become smaller away from the thin-wall case. In the
thin-wall limit the numerical results are found to join into those obtained by
a gradient expansion.Comment: 31 pages, 7 figure
Surface and interface modification of Zr/SiC interface by swift heavy ion irradiation
In this study thin Zr films (135 nm) were deposited on 6H-SiC substrate at room temperature by sputter
deposition. The Zr/SiC couples were irradiated by 167 MeV Xe26+ ions at room temperature at fluences of
5.0 1012, 1.0 1013, 5.0 1013, 2.0 1014, 3.1 1014 and 6.3 1014 ions/cm2. The samples were analysed
before and after irradiation using Rutherford backscattering spectroscopy (RBS), atomic force
microscopy (AFM) and secondary electron microscopy (SEM). The surface morphology from SEM analysis
revealed a homogeneous Zr surface which did not vary with increasing fluences of irradiation. AFM analysis
revealed that the Rrms surface roughness did increase from the as-deposited value of 1.6 nm and then
decrease at higher SHI irradiation fluences to 1.4 nm. RBS results indicate that interface mixing between
Zr and SiC interface occurred and varied linearly with irradiation ion fluence. The value obtained for diffusivity
of Zr shows that the mixing was due to interdiffusion across the interface during a transient melt
phase according to the thermal spike model.http://www.elsevier.com/locate/nimb2016-07-01hb201
Virtual Compton Scattering and Neutral Pion Electroproduction in the Resonance Region up to the Deep Inelastic Region at Backward Angles
We have made the first measurements of the virtual Compton scattering (VCS)
process via the H exclusive reaction in the nucleon resonance
region, at backward angles. Results are presented for the -dependence at
fixed GeV, and for the -dependence at fixed near 1.5 GeV.
The VCS data show resonant structures in the first and second resonance
regions. The observed -dependence is smooth. The measured ratio of
H to H cross sections emphasizes the different
sensitivity of these two reactions to the various nucleon resonances. Finally,
when compared to Real Compton Scattering (RCS) at high energy and large angles,
our VCS data at the highest (1.8-1.9 GeV) show a striking -
independence, which may suggest a transition to a perturbative scattering
mechanism at the quark level.Comment: 20 pages, 8 figures. To appear in Phys.Rev.
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