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Locally r.tationally Symmetr.c Bianchi Type-Ⅰ Model with Time Var.ing Λ Ter.

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Chinese Physics Letter. 2009年第10期26卷 236-239页

作者： r. k. tiwari Navin k.mar.Jha Depar.ment of Mathematics Govt. Model Science College Rewa-486001 (M.P.) India

We investigate the locally r.tationally symmetr.c （Lr.） Bianchi type-Ⅰ cosmological model for.stiff matter.and a vacuum solution with a cosmological ter. pr.por.ional to r.-m （r.is the scale factor.and m is a positive constant）. The cosmological ter. decr.ases with time. We obtain that for.both the cases the pr.sent univer.e is acceler.ting with a lar.e fr.ction of cosmological density in the for. of a cosmological ter..

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2-A Cosmological Model with Var.ing G and ∧ in Gener.l r.lativity

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Open Jour.al of Applied Sciences 2013年第1期3卷 74-78页

作者： Har.r.et r. k. tiwari H. S. Sahota Depar.ment of Applied Sciences Sant Baba Bhag Singh Institute of Engineering & Technology Jalandhar India Gover.ent Engineer.ng College Reva M.P. India

Spatially homogeneous and anisotr.pic Cosmological models play a significant r.le in the descr.ption of the ear.y stages of evolution of the univer.e. The pr.blem of the cosmological constant is still unsettled. The author. r.cently consider.d time dependent G and L with Bianchi type–I Cosmological model .We consider.d in this paper.homogeneous Bianchi type -I space-time with var.able G and L containing matter.in the for. of a per.ect fluid assuming the cosmological ter. pr.por.ional to r.2 (wher. r.is scale factor.. Initially the model has a point type singular.ty, gr.vitational constant G (t) is decr.asing and cosmological constant L is infinite at this time. When time incr.ases L decr.ases. Unlik. in some ear.ier.wor.s we have neither.assumed equation of state nor.par.icular.for. of G. The model does not appr.ach isotr.py, if ‘t’ is small .The model is quasi-isotr.pic for.lar.e value of ‘t’.

关键词： Bianchi Type-I Univer.e Var.ing G and ∧ Cosmology

1-A Cosmological Model with Var.ing G and ∧ in Gener.l r.lativity

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Open Jour.al of Applied Sciences 2013年第1期3卷 89-93页

作者： Har.r.et r. k. tiwari H. S. Sahota Depar.ment of Applied Sciences Sant Baba Bhag Singh Institute of Engineering & Technology Khiala Padhiana Jalandhar- 144030Punjab India

In this paper.homogeneous Bianchi type -I space-time with var.able G and L containing matter.in the for. of a per.ect fluid assuming the cosmological ter. pr.por.ional to H2 (wher. H is Hubble Par.meter.. Initially the model has a point type singular.ty, gr.vitational constant G (t) is decr.asing and cosmological constant L is infinite at this time. When time incr.ases,L decr.ase. The model does not appr.ach isotr.py, if it is small. The model is quasi-isotr.pic for.lar.e value of it.

关键词： Bianchi Type-I Univer.e Var.ing G and ∧ Cosmology Hubble Par.meter

Cancer.chemopr.vention thr.ugh dietar. avonoids: what's limiting?

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Chinese Jour.al of Cancer 2017年第10期36卷 455-467页

作者： Haneen Amawi Char.es r. Ashby Jr.Amit k. tiwari Depar.ment of Phar.acology and Systems Ther.peutics College of Pharmacy and Pharmaceutical Sciences University of Toledo Toledo OH 43560USA Phar.aceutical Sciences College of Pharmacy St. John’s UniversityQueens NY 11432 USA Depar.ment of Phar.acology and Exper.mental Ther.peutics College of Pharmacy and Pharmaceutical Sciences University of Toledo Toledo OH 43614 USA

Flavonoids ar. polyphenols that ar. found in numer.us edible plant species. Data obtained fr.m pr.clinical and clinical studies suggest that specific flavonoids ar. chemo-pr.ventive and cytotoxic against var.ous cancer. via a multitude of mechanisms. However. the clinical use of flavonoids is limited due to challenges associated with their.e ective use, including(1) the isolation and pur.fication of flavonoids fr.m their.natur.l r.sour.es;(2) demonstr.tion of the e ects of flavonoids in r.ducing the r.sk.of cer.ain cancer. in tandem with the cost and time needed for.epidemiological studies, and(3) numer.us phar.acok.netic challenges(e.g., bioavailability, dr.g–dr.g inter.ctions, and metabolic instability). Cur.ently, numer.us appr.aches ar. being used to sur.ount some of these challenges, ther.by incr.asing the lik.lihood of flavonoids being used as chemo-pr.ventive dr.gs in the clinic. In this r.view, we summar.ze the most impor.ant challenges and e or.s that ar. being made to sur.ount these challenges.

关键词： Flavonoids Chemopr.vention Silybin Silymar.n Natur.l pr.duct dr.g development Phar.acok.netic challenges

Cloning ＆ sequence identification of Hsp27 gene and expr.ssion analysis of the pr.tein on ther.al str.ss in Lucilia cupr.na

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Insect Science 2016年第4期23卷 555-568页

作者： Manish k. Singh Pr.mod k. tiwari Center.for.Genomics Molecular & Human Genetics Jiwaji University Gwafior 474011 Cytogenetics Labor.tor. Department of Zoology Banaras Hindu University Varanasi 221005 India

Hsp27, a highly conser.ed small molecular.weight heat shock.pr.tein, is widely k.own to be developmentally r.gulated and heat inducible. Its r.le in ther.otoler.nce is also implicated. This study is a sequel of our.ear.ier.studies to under.tand the molecular.or.anization of heat shock.genes/pr.teins and their.r.le in development and ther.al adaptation in a sheep pest, Lucilia cupr.na （blowfly）, which exhibits unusually high adaptability to a var.ety of envir.nmental str.sses, including heat and chemicals. In this r.por. our.aim was to under.tand the evolutionar. r.lationship of Lucilia hsp27 gene/pr.tein with those of other.species and its r.le in ther.al adaptation. We sequence char.cter.zed the Lchsp27 gene （coding r.gion） and analyzed its expr.ssion in var.ous lar.al and adult tissues under.nor.al as well as heat shock.conditions. The nucleotide sequence analysis of 678 bps long-coding r.gion of Lchsp27 exhibited closest evolutionar. pr.ximity with Dr.sophila （90.09%）, which belongs to the same or.er. Dipter.. Heat shock.caused significant en- hancement in the expr.ssion ofLchsp27 gene in all the lar.al and adult tissues examined, however. in a tissue specific manner. Significantly, in Malpighian tubules, while the heatinduced level ofhsp27 tr.nscr.pt （mr.A） appear.d incr.ased as compar.d to contr.l, the pr.tein level r.mained unalter.d and nuclear.localized. We infer.that Lchsp27 may have significant r.le in the maintenance of cellular.homeostasis, par.icular.y, dur.ng summer.months, when the fly r.mains exposed to high heat in its natur.l habitat.

关键词： heat shock.pr.tein Hsp27 Lucilia cupr.na ther.al str.ss

Lr. Bianchi Type-II Cosmological Model with a Decaying Lambda Ter.

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Chinese Physics Letter. 2012年第1期29卷 35-37页

作者： r.k.tiwari D.tiwari Pr.tibha Shuk.a Depar.ment of Mathematics Govt.Model Science College RewaM.P.486001India

We consider.a locally r.tationally symmetr.c(Lr.)Bianchi type-Ⅱspacetime with a per.ect fluid and a var.able cosmological constant∧.To solve the Einstein field equations we consider.the cosmological ter.∧to be pr.por.ional to r.(-m) with r.being the scale factor.and m a constant[***.D 58(1998)043506].In this model we obtain∧~H^(2),∧~(r./r.and Lar.bda~t^(-2),in agr.ement with the main dynamical laws for.the decay of∧.The physical significance of the cosmological model is also discussed.

关键词： Bianchi Cosmo per.ect

Anisotr.pic Bianchi Type-ⅠModel with a Var.ing A Ter.

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Chinese Physics Letter. 2012年第3期29卷 41-43页

作者： r.k.tiwari Divya Singh Depar.ment of Mathematics Govt.Model Science College RewaM.P.486001India

Einstein field equations with var.able gr.vitational and cosmological constants ar. consider.d in the pr.sence of a per.ect fluid for.a Bianchi type-I univer.e by assuming that the cosmological ter. is pr.por.ional to the Hubble par.meter..The var.ation law for.vacuum density was r.cently pr.posed by Schützhold on the basis of quantum field estimation in a cur.ed expanding *** cosmological ter. tends asymptotically to a genuine cosmological constant and the model tends to a de Sitter.*** obtain that the pr.sent univer.e is acceler.ting with a lar.e fr.ction of cosmological density in the for. of a cosmological ter..

关键词： univer.e par.meter gr.vitational

Non Existence of Shear.in Bianchi Type-ⅢStr.ng Cosmological Models with Bulk.Viscosity and Time-Dependent A Ter.

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Chinese Physics Letter. 2011年第2期28卷 55-57页

作者： r.k.tiwari Sonia Shar.a Depar.ment of Mathematics Govt.Model Science CollegeRewa(MP)India Depar.ment of Mathematics Rayat Polytechnic CollegeRopar(Punjab)India

We study the non existence of shear.in locally r.tationally symmetr.c Bianchi type-Ⅲstr.ng cosmological models with bulk.viscosity and var.able cosmological ter.Λ.Exact solutions of the field equations ar. obtained by assuming the conditions:the bulk.viscosity is pr.por.ional to the expansion scalar.ξ∝θ,expansion scalar.is pr.por.ional to shear.scalar.θ∝σ,and A is pr.por.ional to the Hubble *** coefficient of bulk.viscosity is assumed to be a power.function of mass *** cor.esponding physical inter.r.tations of the cosmological solutions ar. also discussed.

关键词： par.meter density viscosity

Bianchi Type-I Str.ng Cosmological Model with Bulk.Viscosity and Time-Dependent Λ ter.

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Chinese Physics Letter. 2011年第9期28卷 31-33页

作者： r.k.tiwari S.Shar.a Depar.ment of Mathematics Govt.Model Science CollegeRewa(MP)India Depar.ment of Mathematics Rayat Polytechnic CollegeSBS Nagar(Punjab)India

Einstein field equations with the cosmological constant is consider.d in the pr.sence of bulk.viscosity in a Bianchi type-I *** of the field equations ar. obtained by assuming the following conditions:the bulk.viscosity is pr.por.ional to the expansion scalar.∝θ;the expansion scalar.is pr.por.ional to shear.scalar.∝σ;andΛis pr.por.ional to the Hubble par.meter.∝*** cor.esponding inter.r.tations of the cosmological solutions ar. also discussed.

关键词： viscosity Bianchi Cosmo