286 research outputs found
Pseudo Newtonian Potential For a Rotating Kerr Black Hole Embedded in Quintessence
Pseudo-Newtonian Potential has always been a useful tool to discuss the
motion of a particle in space-time to avoid the tedious and nearly impossible
nonlinear computations coming from the field equations of general relativity.
Mukhopadhyay, in 2002, has introduced such a pseudo-Newtonian potential for
rotating Kerr black hole which is efficient enough to replicate the scenario of
the classical mechanics. But there was no such model to explain the dark energy
realm. In 2016 S Ghosh introduced a Lagrangian for such rotating black hole
embedded in quintessence. in this article we obtained a pseudo-Newtonian force
for this new black hole solution embedded quintessence. This paper introduces a
simple computational scheme to evaluate a pseudo-Newtonian force for any
space-time metric. This model possesses at most error corresponding
to general relativistic results. Since we took a popular agent of dark energy,
i.e., quintessence into account, this is a general form of pseudo-Newtonian
force to explain late time accelerating universe. In this paper, it also has
been discussed about the difference between the pseudo-Newtonian force with and
without dark energy effect. This paper also explains the natures of our present
universe and its fate(locally around a black hole when repulsive negative
pressure of dark energy is taken into account).Comment: 108 figure
Dark Energy from pNGB Mediated Dirac Neutrino Condensate
We consider an extension of the Standard Model that provide an unified
description of eV scale neutrino mass and dark energy. An explicit model is
presented by augmenting the Standard Model with an doublet scalar, a
singlet scalar and right handed neutrinos where all of them are assumed to be
charged under a global symmetry. A light pseudo-Nambu-Goldstone Boson,
associated with the spontaneously broken symmetry, acts as a
mediator of an attractive force leading to a Dirac neutrino condensate, with
large correlation length, and a non-zero gap in the right range providing a
cosmologically feasible dark energy scenario. The neutrino mass is generated
through the usual Dirac seesaw mechanism. Parameter space, reproducing viable
dark energy scenario while having neutrino mass in the right ballpark, is
presented.Comment: 12 pages, 2 figures, 2 tables; new clarifications and discussions are
added; updated reference list; matches published versio
HMGCS2 is a key ketogenic enzyme potentially involved in type 1 diabetes with high cardiovascular risk.
Diabetes increases the risk of Cardio-vascular disease (CVD). CVD is more prevalent in type 2 diabetes (T2D) than type 1 diabetes (T1D), but the mortality risk is higher in T1D than in T2D. The pathophysiology of CVD in T1D is poorly defined. To learn more about biological pathways that are potentially involved in T1D with cardiac dysfunction, we sought to identify differentially expressed genes in the T1D heart. Our study used T1D mice with severe hyperglycemia along with significant deficits in echocardiographic measurements. Microarray analysis of heart tissue RNA revealed that the T1D mice differentially expressed 10 genes compared to control. Using Ingenuity Pathway Analysis (IPA), we showed that these genes were significantly involved in ketogenesis, cardiovascular disease, apoptosis and other toxicology functions. Of these 10 genes, the 3-Hydroxy-3-Methylglutaryl-CoA Synthase 2 (HMGCS2) was the highest upregulated gene in T1D heart. IPA analysis showed that HMGCS2 was center to many biological networks and pathways. Our data also suggested that apart from heart, the expression of HMGCS2 was also different in kidney and spleen between control and STZ treated mice. In conclusion, The HMGCS2 molecule may potentially be involved in T1D induced cardiac dysfunction
Stereoselective debromination of aryl-substituted vic-dibromide with indium metal
Debromination of both meso and dl (erythro and threo) aryl-substituted vic-dibromides with indium metal in MeOH leads to trans-alkenes exclusively
Halo uncertainties in electron recoil events at direct detection experiments
The dark matter direct detection rates are highly correlated with the phase
space distribution of dark matter particles in our galactic neighbourhood. In
this paper, we make a systematic study of the impact of astrophysical
uncertainties on electron recoil events at the direct detection experiments
with Xenon and semiconductor detectors. We find that within the standard halo
model there can be up to deviation from the fiducial choice in the
exclusion bounds from these observational uncertainties. For non-standard halo
models, we report a similar deviation from the fiducial standard halo model
when fitted with recent cosmological -body simulations while even larger
deviations are obtained in case of the observational uncertainties.Comment: 27 pages, 16 figures, 3 tables, matches the published versio
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