1,319 research outputs found
The Stability of an Isentropic Model for a Gaseous Relativistic Star
We show that the isentropic subclass of Buchdahl's exact solution for a
gaseous relativistic star is stable and gravitationally bound for all values of
the compactness ratio , where is the total mass and is
the radius of the configuration in geometrized units] in the range, , corresponding to the {\em regular} behaviour of the solution. This
result is in agreement with the expectation and opposite to the earlier claim
found in the literature.Comment: 9 pages (including 1 table); accepted for publication in GR
Shape Invariant Potential and Semi-Unitary Transformations (SUT) for Supersymmetric Harmonic Oscillator in T4-Space
Constructing the Semi - Unitary Transformation (SUT) to obtain the
supersymmetric partner Hamiltonians for a one dimensional harmonic oscillator,
it has been shown that under this transformation the supersymmetric partner
loses its ground state in T^{4}- space while its eigen functions constitute a
complete orthonormal basis in a subspace of full Hilbert space.
Keywords: Supersymmetry, Superluminal Transformations, Semi Unitary
Transformations.
PACS No: 14.80L
Twisted Virtual Braid Group
In this paper we study some subgroups and their decompositions in semi-direct
product of the twisted virtual braid group . In particular, the twisted
virtual pure braid group is the kernel of an epimorphism of
onto the symmetric group . We find the set of generators and defining
relations for and show that . Further we
prove that is a semi-direct product of some subgroup and abelian group
. As corollary we get that the virtual pure braid group
is a subgroup of . Also, we construct some other epimorphism of
onto . Its kernel, is an analogous of . We find its set of
generators and defining relations and construct its decomposition in a
semi-direct product.Comment: 20 pages, 2 figures, uses overlea
A Safe Vaccine (DV-STM-07) against Salmonella Infection Prevents Abortion and Confers Protective Immunity to the Pregnant and New Born Mice
Pregnancy is a transient immuno-compromised condition which has evolved to avoid the immune rejection of the fetus by the maternal immune system. The altered immune response of the pregnant female leads to increased susceptibility to invading pathogens, resulting in abortion and congenital defects of the fetus and a subnormal response to vaccination. Active vaccination during pregnancy may lead to abortion induced by heightened cell mediated immune response. In this study, we have administered the highly attenuated vaccine strain ΔpmrG-HM-D (DV-STM-07) in female mice before the onset of pregnancy and followed the immune reaction against challenge with virulent S. Typhimurium in pregnant mice. Here we demonstrate that DV-STM-07 vaccine gives protection against Salmonella in pregnant mice and also prevents Salmonella induced abortion. This protection is conferred by directing the immune response towards Th2 activation and Th1 suppression. The low Th1 response prevents abortion. The use of live attenuated vaccine just before pregnancy carries the risk of transmission to the fetus. We have shown that this vaccine is safe as the vaccine strain is quickly eliminated from the mother and is not transmitted to the fetus. This vaccine also confers immunity to the new born mice of vaccinated mothers. Since there is no evidence of the vaccine candidate reaching the new born mice, we hypothesize that it may be due to trans-colostral transfer of protective anti-Salmonella antibodies. These results suggest that our vaccine DV-STM-07 can be very useful in preventing abortion in the pregnant individuals and confer immunity to the new born. Since there are no such vaccine candidates which can be given to the new born and to the pregnant women, this vaccine holds a very bright future to combat Salmonella induced pregnancy loss
Analysis of MAGSAT data of the Indian region
Progress in the development of software for reading MAGSAT data tapes and for the reduction of anomaly data, and in the preparation of data for magnetic anomaly maps is reported
P01.46. Assessment of autonomic tone at rest and during meditation in a longitudinal study of an eight-week meditation intervention
Razlučivanje Zemljine rotacije i atmosferske cikulacije Walshovim spektrima:nesinusoidalna perspektiva
Lambeck and Hopgood (1981, 1982) have made a comparative study of spectral characteristics of the angular momentum of atmospheric circulation and fluctuations in the Length-of-Day (LOD) data. The Fourier analysis of these data reveals a good correlation between the two processes, including a large spread of power in the range of a 20- to 70-month period. We re-examine here the above two time series by using the Walsh spectral analysis, which seems to be more appropriate for series with sharp peaks and reversals. The comparative study shows that in addition to 12-, 6- and 3-month seasonal terms, the present work discovers statistically significant (90% confidence interval) periods of (i) 26 months (hitherto weakly resolved) associated with a quasibiennial term, and (ii) 40 ± 4 months in both the data. The resolution of the spread components removes meteorological noise uncertainity from astronomical observations of LOD in the study of the excitation mechanism of solid earth
SARS CoV-2 aggravates cellular metabolism mediated complications in COVID-19 infection.
Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the primary causative organism in corona virus disease-19 (COVID-19) infections, is a novel member of the human coronavirus family which was first identified in Wuhan, China, towards the end of 2019. This letter reveals new vital missing links in our current understanding of the mechanisms that lead to cell death triggered by ferroptotic stress in COVID-19 infection. It further reveal the importance of homocysteine mediated trans-sulfuration pathway in COVID-19 infection. Hence, Vitamin B6, folic acid, and Vitamin B12 should be incorporated in the treatment regimen for SARS CoV-2 infections to suppress complications, as the virus mediates altered host cell metabolism
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