22,015 research outputs found
Types of hyperodontic anomalies in permanent dentition: Report of 5 cases
Hyperodontia is a term used to express for the teeth more than the normal series in either dentition. Supernumerary teeth are developmental anomalies and are not uncommonly observed in permanent dentition of either jaw. Supernumerary teeth (multiple) have been reported with certain syndromes but multiple supernumeraries in non-syndromic individual have not been frequently reported. Several theories of this kind of developmental anomaly have been proposed but the precise etiology of non-syndromic supernumerary teeth is not clearly known. In patients with non-syndromic supernumerary teeth heredity factor has been proposed in several reports, therefore family history should be carefully explored. This article provides series of case reports of all common types of supernumerary teeth seen in the permanent dentition, along with literature review, anatomy, etiology, incidences and treatment options suggested by various authors have been discussed.  
Vector meson masses in hot nuclear matter : the effect of quantum corrections
The medium modification of vector meson masses is studied taking into account
the quantum correction effects for the hot and dense hadronic matter. In the
framework of Quantum Hadrodynamics, the quantum corrections from the baryon and
scalar meson sectors were earlier computed using a nonperturbative variational
approach through a realignment of the ground state with baryon-antibaryon and
sigma meson condensates. The effect of such corrections was seen to lead to a
softer equation of state giving rise to a lower value for the compressibility
and, an increase in the in-medium baryonic masses than would be reached when
such quantum effects are not taken into account. These quantum corrections
arising from the scalar meson sector result in an increase in the masses of the
vector mesons in the hot and dense matter, as compared to the situation when
only the vacuum polarisation effects from the baryonic sector are taken into
account.Comment: 13 pages revtex file, 6 figure
Effect of shear force on the separation of double stranded DNA
Using the Langevin Dynamics simulation, we have studied the effects of the
shear force on the rupture of short double stranded DNA at different
temperatures. We show that the rupture force increases linearly with the chain
length and approaches to the asymptotic value in accordance with the
experiment. The qualitative nature of these curves almost remains same for
different temperatures but with a shift in the force. We observe three
different regimes in the extension of covalent bonds (back bone) under the
shear force.Comment: 4 pages, 4 figure
Role of Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) as a Better Tool for Early Diagnosis of Human Rabies
Structure of the Vacuum in Nuclear Matter - A Nonperturbative Approach
We compute the vacuum polarisation correction to the binding energy of
nuclear matter in the Walecka model using a nonperturbative approach. We first
study such a contribution as arising from a ground state structure with
baryon-antibaryon condensates. This yields the same results as obtained through
the relativistic Hartree approximation of summing tadpole diagrams for the
baryon propagator. Such a vacuum is then generalized to include quantum effects
from meson fields through scalar-meson condensates. The method is applied to
study properties of nuclear matter and leads to a softer equation of state
giving a lower value of the incompressibility than would be reached without
quantum effects. The density dependent effective sigma mass is also calculated
including such vacuum polarisation effects.Comment: 26 pages including 5 eps files, uses revtex style; PACS number:
21.65.+f,21.30.+
Resolution of puzzles from the LSND, KARMEN, and MiniBooNE experiments
This work has attempted to reconcile puzzling neutrino oscillation results
from the LSND, KARMEN and MiniBooNE experiments. We show that the LSND evidence
for oscillations, its long-standing
disagreement with the results from KARMEN, and the anomalous event excess
observed by MiniBooNE in and data could all be
explained by the existence of a heavy sterile neutrino (). All these
results are found to be consistent with each other assuming that the is
created in neutral-current interactions and decays radiatively into a
photon and a light neutrino. Assuming the is produced through mixing
with , the combined analysis of the LSND and MiniBooNe excess events
suggests that the mass is in the range from 40 to 80 MeV, the mixing
strength is , and the lifetime is
s. Surprisingly, this LSND-MiniBooNE parameters
window is found to be unconstrained by the results from the most sensitive
experiments searching for heavy neutrino. We set new limits on
for the LSND-MiniBooNE favorable mass region from the precision measurements of
the Michel spectrum by the TWIST experiment. The results obtained provide a
strong motivation for a sensitive search for the in a near future
decay or neutrino experiments, which fit well in the existing/planned
experimental programs at CERN or FNAL. The question of whether the heavy
neutrino is Dirac or Majorana particle is briefly discussed.Comment: 24 pages, 28 figures, version to appear in PR
Chiral symmetry breaking, color superconductivity and color neutral quark matter: a variational approach
We investigate the vacuum realignment for chiral symmetry breaking and color
superconductivity at finite density in Nambu-Jona-Lasinio model in a
variational method. The treatment allows us to investigate simultaneous
formation of condensates in quark antiquark as well as in diquark channels. The
methodology involves an explicit construction of a variational ground state and
minimisation of the thermodynamic potential. Color and electric charge
neutrality conditions are imposed through introduction of appropriate chemical
potentials. Color and flavor dependent condensate functions are determined
through minimisation of the thermodynamic potential. The equation of state is
calculated. Simultaneous existence of a mass gap and superconducting gap is
seen in a small window of quark chemical potential within the model when charge
neutrality conditions are not imposed. Enforcing color and electric charge
neutrality conditions gives rise to existence of gapless superconducting modes
depending upon the magnitude of the gap and the difference of the chemical
potentials of the condensing quarks.Comment: 13 pages, 6 figures,to appear in Phys. Rev.
Current-Induced Spin Polarization in Gallium Nitride
Electrically generated spin polarization is probed directly in bulk GaN using
Kerr rotation spectroscopy. A series of n-type GaN epilayers are grown in the
wurtzite phase both by molecular beam epitaxy (MBE) and metalorganic chemical
vapor deposition (MOCVD) with a variety of doping densities chosen to broadly
modulate the transverse spin lifetime, T2*. The spin polarization is
characterized as a function of electrical excitation energy over a range of
temperatures. Despite weak spin-orbit interactions in GaN, a current-induced
spin polarization (CISP) is observed in the material at temperatures of up to
200 K.Comment: 16 pages, 3 figure
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