372 research outputs found
Canonical quantization of the relativistic particle in static spacetimes
We perform the canonical quantization of a relativistic spinless particle
moving in a curved and static spacetime. We show that the classical theory
already describes at the same time both particle and antiparticle. The analyses
involves time-depending constraints and we are able to construct the
two-particle Hilbert space. The requirement of a static spacetime is necessary
in order to have a well defined Schr\"odinger equation and to avoid problems
with vacuum instabilities. The severe ordering ambiguities we found are in
essence the same ones of the well known non-relativistic case.Comment: Revtex, 9 page
Phase Transition and Hybrid Star in a Nonlinear model
The phase transition between the nuclear matter and the quark matter is
examined. The relativistic mean field theory(RMF) is consider with interacting
nucleons and mesons using TM1 parameter set for the nuclear matter equations of
state. It is found that the trasition point depends on coupling constant
and bag pressure. From the study of the structure of a hybrid
neutron star, it is observed that the star contains quark matter in the
interior and neutron matter on the outer perifery.Comment: 8 pages, 7 figures, to appear in Int. J. Mod. Phy.
An observational study of clinicoetiological profile of stroke patients in a new tertiary care hospital in North Odisha, India
Background: Stroke is one of the leading causes of morbidity and mortality in India. The objective was to study the clinical profile, risk factors, neurological characters, pattern of brain stroke, areas of brain affected as per CT scan findings in patients with stroke.Methods: This observational study was carried out from June 2018 to Jan 2019 of all new patients admitted with stroke in Pandit Raghunath Murmu Medical College and Hospital, Baripada, Mayurbhanj, Odisha, India.Results: The incidence of stroke is maximum in 46-60 years of age group. The average age+SD was 59.3+13.5 in our study. 274 (46.52%) patients had ischemic stroke and 315 (53.48%) patients had hemorrhagic stroke. The male to female ratio was 1.46:1. Anterior circulation (86.42%) was the most common territory involved in the brain. The most common risk factor was hypertension with 77.76% followed by dyslipidemia (53.99%). The most common clinical presentation was hemiplegia (85.23%).Conclusions: The incidence of stroke is maximum in 46-60 years of age group. The average age+SD was 59.3+13.5 in our study. 274 (46.52%) patients had ischemic stroke and 315 (53.48%) patients had hemorrhagic stroke. The male to female ratio was 1.46:1. Anterior circulation (86.42%) was the most common territory involved in the brain. The most common risk factor was hypertension with 77.76% followed by dyslipidemia (53.99%). The most common clinical presentation was hemiplegia (85.23%).
Monodromy Matrix in the PP-Wave Limit
We construct the monodromy matrix for a class of gauged WZWN models in the
plane wave limit and discuss various properties of such systems.Comment: 16 page
U(1,1)--Invariant Generation of Charges for Einstein--Maxwell--Dilaton--Axion Theory
The action of the isometry subgroup which preserves the trivial values of the
fields is studied for the stationary D=4 Einstein--Maxwell--Dilaton--Axion
theory. The technique for generation of charges and the corresponding procedure
for construction of new solutions is formulated. A solution describing the
double rotating dyon with independent values of all physical charges is
presented.Comment: 14 pages, RevTex, no figurie
Kaluza-Klein Black Holes in String Theory
Exact solutions of heterotic string theory corresponding to four-dimensional
magnetic black holes in supergravity are described. The solutions
describe the black holes in the throat limit, and consist of a tensor product
of an WZW orbifold with the linear dilaton vacuum, supersymmetrized to
world sheet SUSY. One dimension of the model is interpreted as
a compactified fifth dimension, leading to a four dimensional solution with a
Kaluza-Klein gauge field having a magnetic monopole background; this
corresponds to a solution in supergravity, since that theory is obtained
by dimensional reduction of string theory.Comment: 13p. uses Harvma
An Infinite Dimensional Symmetry Algebra in String Theory
Symmetry transformations of the space-time fields of string theory are
generated by certain similarity transformations of the stress-tensor of the
associated conformal field theories. This observation is complicated by the
fact that, as we explain, many of the operators we habitually use in string
theory (such as vertices and currents) have ill-defined commutators. However,
we identify an infinite-dimensional subalgebra whose commutators are not
singular, and explicitly calculate its structure constants. This constitutes a
subalgebra of the gauge symmetry of string theory, although it may act on
auxiliary as well as propagating fields. We term this object a {\it weighted
tensor algebra}, and, while it appears to be a distant cousin of the
-algebras, it has not, to our knowledge, appeared in the literature before.Comment: 14 pages, Plain TeX, report RU93-8, CTP-TAMU-2/94, CERN-TH.7022/9
Soliton solution in dilaton-Maxwell gravity
The inverse scattering problem method application to construction of exact
solution for Maxwell dilaton gravity system ia considered. By use of Belinsky
and Zakharov L - A pair the solution of the theory is constructed. The rotating
Kerr - like configuration with NUT - parameter is obtained.Comment: 8 pages in LaTex; published in Gen. Rel. Grav. pp. 32 (2000)
2219-222
Evaluation of the Immunoprotective Potential of Recombinant Paraflagellar Rod Proteins of Trypanosoma evansi in Mice
Trypanosomosis, caused by Trypanosoma evansi, is an economically significant disease of livestock. Systematic antigenic variation by the parasite has undermined prospects for the development of a protective vaccine that targets the immunodominant surface antigens, encouraging exploration of alternatives. The paraflagellar rod (PFR), constituent proteins of the flagellum, are prominent non-variable vaccine candidates for T. evansi owing to their strategic location. Two major PFR constituent proteins, PFR1 (1770bp) and PFR2 (1800bp), were expressed using Escherichia coli. Swiss albino mice were immunized with the purified recombinant TePFR1 (89KDa) and TePFR2 (88KDa) proteins, as well as with the mix of the combined proteins at equimolar concentrations, and subsequently challenged with virulent T. evansi. The PFR-specific humoral response was assessed by ELISA. Cytometric bead-based assay was used to measure the cytokine response and flow cytometry for quantification of the cytokines. The recombinant TePFR proteins induced specific humoral responses in mice, including IgG1 followed by IgG2a and IgG2b. A balanced cytokine response induced by rTePFR 1 and 2 protein vaccination associated with extended survival and improved control of parasitemia following lethal challenge. The observation confirms the immunoprophylactic potential of the covert antigens of T. evansi
Scattering of Four-Dimensional Black Holes
The moduli space metric for an arbitrary number of extremal black holes in
four dimensions with arbitrary relatively supersymmetric charges is found.Comment: 16 pages, REVTeX; references adde
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