14,398 research outputs found
G_2 invariant 7D Euclidean super Yang-Mills theory as a higher-dimensional analogue of the 3D super-BF theory
A formulation of the N_T=1, D=8 Euclidean super Yang-Mills theory with
generalized self-duality and reduced Spin(7)-invariance is given which avoids
the peculiar extra constraints of Nishino and Rajpoot, hep-th/0210132. Its
reduction to 7 dimensions leads to the G_2-invariant N_T=2, D=7 super
Yang-Mills theory which may be regarded as a higher-dimensional analogue of the
N=2, D=3 super-BF theory. When reducing further that G_2-invariant theory to 3
dimensions one gets the N_T=2 super-BF theory coupled to a spinorial
hypermultiplet.Comment: 9 pages, Late
A short term comparative evaluation of the efficacy of diode laser with desensitizing toothpastes and mouthwashes in the treatment of dentinal hypersensitivity
Treatment of dentinal hypersensitivity (DH) has always been challenging with a wide variety of therapeutic options, in-office and home care. The study objective was to compare the clinical efficacy of diode laser [DL] with four commercially available des
Salivary and gingival crevicular fluid histatin in periodontal health and disease
Objectives: Histatin, with its anti bacterial, anti protease, and wound closure stimulating property might influence
the pathogenesis of periodontal disease. This study assessed the presence of histatin in gingival crevicular fluid
(GCF); the levels of salivary and GCF histatin in periodontal disease.
Material and methods: It was a cross sectional study that included systemically healthy forty five subjects (22 males
and 23 females) between the age group of 20 to 45 years. Based on Gingival Index (Loe and Silness ,1963) and
Russell's Periodontal Index they were grouped as 15 healthy (Group 1), 15 gingivitis (Group 2), and 15 periodontitis (Group 3) subjects. Whole pooled unstimulated saliva was collected by asking the patient to spit in a sterile
container and GCF samples were collected using a micropipette from all the subjects. Histatin levels were assessed
using Enzyme Linked Immunosorbent Assay (ELISA). The intergroup comparison was done by ANOVA and Mann
Whitney U Test was done for pair wise comparison.
Results: The results of this study show that histatin is present in saliva and gingival crevicular fluid. When the
salivary histatin levels were compared it was found that the levels of histatin increase from health to periodontitis
but the levels of histatin in the gingival crevicular fluid and saliva had no correlation with severity of periodontal
disease as there was no statistically significant difference between the three groups.
Conclusions: It can be concluded that histatin cannot be used as a potential marker of periodontal disease
A clinical study of the effect of calcium sodium phosphosilicate on dentin hypersensitivity
Objective: Dentinal hypersensitivity is a commonly encountered problem with varied treatment options for its management.
A large number of home use products have been tested and used for the management of dentinal hypersensitivity.
This 8 week clinical trial investigates the temporal efficacy of commercially available calcium sodium
phosphosilicate containing toothpaste in comparison to a potassium nitrate containing toothpaste.
Methods: A total 20 subjects between the ages of 18 to 65 years were screened for a visual analogue score (VAS) for
sensitivity of 5 or more by testing with a cold stimulus and randomly divided into test and positive control groups.
Baseline sensitivity VAS scores to air evaporative stimulus were recorded for minimum two teeth. The subjects
were prescribed respective dentifrices and revaluated for sensitivity scores at 2, 4 and 8 weeks.
Results:The study demonstrated reduction in symptoms for all treatment groups from baseline to 2, 4 and 8 weeks.
The calcium sodium phosphosilicate group showed a higher degree of effectiveness at reducing hypersensitivity to
air evaporative stimulus at 2 weeks, than commercially available potassium nitrate. However, there was no significant
difference in scores of subjects using the calcium sodium phosphosilicate toothpaste as compared to potassium
nitrate at 4 weeks and 8 weeks.
Conclusion: Calcium sodium phosphosilicate showed greater reduction in sensitivity compared to potassium nitrate
at an earlier stage which is of high clinical value. However, based on the findings of the present study long term
effects of calcium sodium phosphosilicate seem to be less promising than previously claimed
Coset Construction of Gravitational Instantons
We study Ricci-flat metrics on non-compact manifolds with the exceptional
holonomy . We concentrate on the metrics which are defined on
. If the homogeneous coset spaces have weak ,
SU(3) holonomy, the manifold may have
holonomy metrics. Using the formulation with vector fields, we investigate the
metrics with holonomy on . We have found the explicit volume-preserving vector fields on
these manifold using the elementary coordinate parameterization. This
construction is essentially dual to solving the generalized self-duality
condition for spin connections. We present most general differential equations
for each coset. Then, we develop the similar formulation in order to calculate
metrics with holonomyComment: 29 pages, no figure; (v2) Errors are corrected ; (v3) Some
explanations are added. More general differential equations for SU(3)/U(1)
coset are give
Multi-frequency, Multi-Epoch Study of Mrk 501: Hints for a two-component nature of the emission
Since the detection of very high energy (VHE) -rays from Mrk 501, its
broad band emission of radiation was mostly and quite effectively modeled using
one zone emission scenario. However, broadband spectral and flux variability
studies enabled by the multiwavelength campaigns carried out during the recent
years have revealed rather complex behavior of Mrk 501. The observed emission
from Mrk 501 could be due to a complex superposition of multiple emission
zones. Moreover new evidences of detection of very hard intrinsic -ray
spectra obtained from {\it Fermi}--LAT observations have challenged the
theories about origin of VHE -rays. Our studies based on {\it
Fermi}--LAT data indicate the existence of two separate components in the
spectrum, one for low energy -rays and the other for high energy
-rays. Using multiwaveband data from several ground and space based
instruments, in addition to HAGAR data, the spectral energy distribution of
Mrk~501 is obtained for various flux states observed during 2011. In the
present work, this observed broadband spectral energy distribution is
reproduced with a leptonic, multi-zone Synchrotron Self-Compton model.Comment: Published in Astrophysical Journal (ApJ
Phase transition and hybrid star in a SU(2) chiral sigma model
We use a modified SU(2) chiral sigma model to study nuclear matter at high
density using mean field approach. We also study the phase transition of
nuclear matter to quark matter in the interior of highly dense neutron stars.
Stable solutions of Tolman-Oppenheimer-Volkoff equations representing hybrid
stars are obtained with a maximum mass of 1.69 , radii around 9.3
kms and a quark matter core constituting nearly 55-85 % of the star radii.Comment: 19 pages, 9 figures, accepted for Mod. Phys. Letts.
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