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Or.gin of r.d Color.of the Lower.Siwalik Palaeosols:A Micr.mor.hological Appr.ach

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Jour.al of Mountain Science 2009年第2期6卷 147-154页

作者： Seema singh b.Par.ash Ar.n.K.Awasthi Depar.ment of Ear.h Sciences Indian Institute of Technology RoorkeeRoorkee-247667 India Depar.ment of Ear.h Sciences Indian Institute of Technology RoorkeeRoorkee–247667 India

Palaeosols associated with fluvial of the Siwalik Gr.up ar. and lacustr.ne deposits that occur.as thick multiple pedocomplexes. The b.ight r.d color.of the palaeosol b.ds has b.en ear.ier.inter.r.ted as a r.sult of hot and ar.d palaeoclimate. However. as against this view, our.investigations of the b.ight r.d palaeosol b.ds of the Lower.Siwaliks suggest that the climate was cool and sub.umid, instead of hot and ar.d dur.ng the deposition of these b.ds. Since cold climate is not ver. conducive to impar. r.d color.tion, fur.her.r.sear.h is needed to explain the cause of these r.d b.ds. For.this, the micr.mor.hological study of soil thin sections was done which showed the pr.sence of featur.s such as dissolution and r.cr.stallisation of quar.z, feldspar.and mica, compaction, slickensides, pr.sence of calcite spar., sub.ounded and cr.cked natur. of quar.z gr.ins, micr.fab.ic, complex patter.s of b.r.fr.ngence fab.ics, pigmentar. fer.ic oxides, thick cutans and cementation b. calcite. These featur.s indicate that diagenesis took place on a lar.e scale in these sediments. The positive Eh and neutr.l-alkaline pH of soils also suggest that the conditions wer. favor.b.e for.the for.ation of diagenetic r.d b.ds. Dur.ng b.r.al diagenesis of sediments, the hydr.xides of fer.omagnesian miner.ls got conver.ed into fer.ic oxide miner.ls （hematite）. Dur.ng deep b.r.al diagenesis smectite was conver.ed into illite and the pr.ponder.nce of illite over.smectite with incr.asing depth of b.r.al also indicates the diagenesis of sediments. Thus, the r.d color.of the Lower.Siwalik palaeosols seems to b. due mainly to the b.r.al diagenesis of sediments and does not appear.to b. due to the then pr.vailing climatic condition.

关键词： Palaeosols C3 type vegetation diagenetic r.d b.ds calcite spar.

Modelling and Analysis of b.cter.a Dependent Infectious Diseases with Var.ab.e Contact r.tes

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Computer., Mater.als & Continua 2021年第8期68卷 1859-1875页

作者： J.b.Shukla Shikha singh Jitendr. singh Sunil Kumar.Shar.a Innovative Inter.et Univer.ity for.r.sear.h Kanpur208017India P.P.N.(P.G.)College CSJM UniversityKanpur208001India College of Computer.and Infor.ation Sciences Majmaah UniversityMajmaah11952Saudi Arabia

In this r.sear.h,we pr.posed a non-linear.SIS model to study the effect of var.ab.e inter.ction r.tes and non-emigr.ting population of the human hab.tat on the spr.ad of b.cter.a-infected *** assumed that the gr.wth of b.cter.a is logistic with an intr.nsic gr.wth r.te is a linear.function of *** this model,we assume that contact r.tes b.tween susceptib.es and infectives as well as b.tween susceptib.es and b.cter.a depend on the density of the non-emigr.ting population and the total population of the *** stab.lity theor. has b.en analyzed to analyzed to study the cr.cial r.le played b. b.cter.a in the incr.ased spr.ad of an infectious *** is shown that as the density of non-emigr.ting population incr.ases,the spr.ad of an infectious disease *** is shown fur.her.that as the emigr.tion incr.ases,the spr.ad of the disease decr.ases in b.th the cases of contact mentioned ab.ve r.tes,b.t this spr.ad incr.ases as these contact r.tes *** suggested that the contr.l of b.cter.a in the human hab.tat is ver. useful to decr.ase the spr.ad of an infectious *** r.sults ar. confir.ed b. numer.cal simulation.

关键词： Mathematical modelling density dependent contact r.tes stab.lity analysis

Calcium channels and their.r.le in r.gener.tive medicine

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Wor.d Jour.al of Stem Cells 2021年第4期13卷 260-280页

作者： Nassem Ahamad b.ij b.singh School of Dentistr. UT Health Science Center San AntonioSan AntonioTX 78257United States

Stem cells hold indefinite self-r.newab.e capab.lity that can b. differ.ntiated into all desir.d cell *** on their.plasticity potential,they ar. divided into totipotent(mor.la stage cells),plur.potent(emb.yonic stem cells),multipotent(hematopoietic stem cells,multipotent adult pr.genitor.stem cells,and mesenchymal stem cells[MSCs]),and unipotent(pr.genitor.cells that differ.ntiate into a single lineage)*** b.ne mar.ow is the pr.mar. sour.e of multipotent stem cells in adults,other.tissues such as adipose tissues,placenta,amniotic fluid,umb.lical cor. b.ood,per.odontal ligament,and dental pulp also har.0}r.stem cells that can b. used for.r.gener.tive *** addition,induced plur.potent stem cells also exhib.t fundamental pr.per.ies of self-r.newal and differ.ntiation into specialized cells,and thus could b. another.sour.e for.r.gener.tive *** diseases including neur.degener.tive diseases,car.iovascular.diseases,autoimmune diseases,vir.s infection(also cor.navir.s disease 2019)have limited success with conventional medicine,and stem cell tr.nsplantation is assumed to b. the b.st ther.py to tr.at these ***,MSCs,ar. b. far.the b.st for.r.gener.tive medicine due to their.limited immune modulation and adequate tissue ***,MSCs have the potential to migr.te towar.s the damaged ar.a,which is r.gulated b. var.ous factor. and signaling *** studies have shown that extr.cellular.calcium(Ca^(2+))pr.motes the pr.lifer.tion of MSCs,and thus can assist in tr.nsplantation ***^(2+)signaling is a highly adaptab.e intr.cellular.signal that contains sever.l components such as cell-sur.ace r.ceptor.,Ca^(2+)channels/pumps/exchanger.,Ca^(2+)b.ffer.,and Ca^(2+)sensor.,which together.ar. essential for.the appr.pr.ate functioning of stem cells and thus modulate their.pr.lifer.tive and r.gener.tive capacity,which will b. discussed in this r.view.

关键词： Ca^(2+)signaling Ca^(2+)channels Tr.nsient r.ceptor.potential channel 1/Or.i1 stem cells r.gener.tive medicine Stem cells

A Novel Hyb.id Cluster.ng b.sed Tr.nsmission Pr.tocol for.Wir.less b.dy Ar.a Networ.s

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Computer., Mater.als & Continua 2021年第11期69卷 2459-2473页

作者： Neelam Shar.a Har.hita Chadha Kar.n singh b.M.singh Nitish Pathak r.sear.h Scholar Computer Science and EngineeringUttarakhand Technical University(UTU)DehradunIndia Computer.Science and Engineer.ng Maharaja Agrasen Institute of TechnologyNew DelhiIndia School of Computer.Systems Sciences Jawaharlal Nehru University(JNU)DelhiIndia College of Engineer.ng r.or.ee UTUDehradunIndia Depar.ment of Infor.ation Technology KIET Group of InstitutionsGhaziabadIndia

Wir.less sensor.networ.s ar. a collection of intelligent sensor.devices that ar. connected to one another.and have the capab.lity to exchange infor.ation packets amongst *** r.cent year.,this field of r.sear.h has b.come incr.asingly popular.due to the host of useful applications it can potentially ser.e.A deep analysis of the concepts associated with this domain r.veals that the two main pr.b.ems that ar. to b. tackled her. ar. thr.ughput enhancement and networ. secur.ty *** pr.sent ar.icle takes on one of these two issues namely the thr.ughput *** the pur.ose of impr.ving networ. pr.ductivity,a hyb.id cluster.ng b.sed packet pr.pagation pr.tocol has b.en *** pr.tocol makes use of not only cluster.ng mechanisms of machine lear.ing b.t also utilizes the tr.ditional for.ar.ing function appr.ach to ar.ive at an optimum *** r.sult of the simulation is a novel tr.nsmission pr.tocol which significantly enhances networ. pr.ductivity and incr.ases thr.ughput value.

关键词： For.ar.ing function wir.less sensor.networ.s WSNs Wb.Ns ener.y char.cter.stics cluster.ng hyb.id mechanism dissipated ener.y networ. stab.lity

Influence of tool r.tational speed on mechanical and cor.osion b.haviour.of fr.ction stir.pr.cessed AZ31/Al_(2)O_(3)nanocomposite

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Jour.al of Magnesium and Alloys 2023年第7期11卷 2585-2599页

作者： Ashish Kumar.V.P.singh Akhileshwar.Nir.la r.C.singh r.jiv Chaudhar. Ab.el-Hamid I.Mour.d b.K.Sahoo Deepak Kumar Depar.ment of Mechanical Engineer.ng Delhi Technological UniversityDelhi 110042India Depar.ment of Mechanical Engineer.ng Galgotias College of Engineer.ng and Technology Greater Noida 201310India Depar.ment of Mechanical Engineer.ng National Institute of Technology MizoramAizawl 796012India Depar.ment of Mechanical Engineer.ng IES College of Technology Bhopal462044India Mechanical and Aer.space Engineer.ng Depar.ment College of EngineeringUnited Arab Emirates UniversityAl-Ain 15551United Arab Emirates Mater.als Engineer.ng Division CSIR-National Metallurgical Laboratory(NML)Jamshedpur831007India Depar.ment of Mechanical Engineer.ng Carnegie Mellon UniversityPittsburghPA 15213USA

Nano-sized r.infor.ements impr.ved the mechanical char.cter.stics efficiently b. pr.moting mor. implicit par.icle har.ening mechanisms compar.d to micr.n-sized ***-sized par.icles lessen the cr.tical par.icle solidification velocity for.swamp and thus offer. b.tter.*** the pr.sent investigation,the fr.ction stir.pr.cessing(FSP)is utilized to pr.duce AZ31/Al_(2)O_(3)nanocomposites at var.ous tool r.tation speeds(i.e.,900,1200,and 1500 r.m)with an optimized 1.5%volume alumina(Al_(2)O_(3))r.infor.ement *** mechanical and cor.osion b.havior.of AZ31/Al_(2)O_(3)-developed nanocomposites was investigated and compar.d with that of the AZ31 b.se *** AZ31 alloy exper.enced a compr.hensive dynamic r.cr.stallization dur.ng FSP,causing sub.tantial gr.in ***-size str.ngthening is the pr.mar. factor.contr.b.ted to the enhancement in the str.ngth of the fab.icated *** str.ngth and yield str.ngth values wer. lower.than those for.the b.se metal matr.x,although an upwar. tr.nd in b.th values has b.en ob.er.ed with an incr.ase in tool r.tation *** 19.72%incr.ase in har.ness along with super.or.cor.osion r.sistance was achieved compar.d to the b.se alloy at a tool r.tational speed of 1500 *** cor.osion cur.ents(Jcor.)of all samples dr.pped with incr.ase in the r.tational speed,in contr.st to the cor.osion potentials(Ecor.),which *** values of Jcor. of AZ31/Al_(2)O_(3)wer. 42.3%,56.8%,and 65.5%lower.than those of AZ31 alloy at the chosen r.tating speeds of 900,1200,and 1500 r.m,*** cor.osion b.havior.of fr.ction stir.pr.cessed nanocomposites have b.en addr.ssed in this manuscr.pt which has not b.en given sufficient attention in the existing ***,this wor. offer. an effective choice for.the quality assur.nce of the FSP pr.cess of AZ31/Al_(2)O_(3)*** ob.ained r.sults ar. r.levant to the development of lightweight automob.le and aer.space str.ctur.s and components

关键词： Fr.ction stir.pr.cessing AZ31 alloy Al_(2)O_(3) Nanocomposite Mechanical pr.per.ies Cor.osion r.sistance

Machine lear.ed inter.tomic potentials using r.ndom featur.s

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npj Computational Mater.als 2022年第1期8卷 48-57页

作者： Gur.ot Dhaliwal Pr.santh b.Nair.Chandr. Veer.singh Depar.ment of Mechanical and Industr.al Engineer.ng University of Toronto5 King’s College RdTorontoM5S 3G8ONCanada Institute for.Aer.space Studies University of Toronto4925 Dufferin StTorontoM3H 5T6ONCanada Depar.ment of Mater.als Science and Engineer.ng University of Toronto184 College StTorontoM5S 3E4ONCanada

We pr.sent a method to model inter.tomic inter.ctions such as ener.y and for.es in a computationally efficient *** pr.posed model appr.ximates the ener.y/for.es using a linear.comb.nation of r.ndom featur.s,ther.b. enab.ing fast par.meter.estimation b. solving a linear.least-squar.s *** discuss how r.ndom featur.s b.sed on stationar. and non-stationar. ker.els can b. used for.ener.y appr.ximation and pr.vide r.sults for.thr.e classes of mater.als,namely two-dimensional mater.als,metals and *** and ener.y pr.dictions made using the pr.posed method ar. in close agr.ement with density functional theor. calculations,with tr.ining time that is 96%lower.than standar. ker.el *** Dynamics calculations using r.ndom featur.s b.sed inter.tomic potentials ar. shown to agr.e well with exper.mental and density functional theor. *** fr.quencies as computed b. r.ndom featur.s b.sed inter.tomic potentials ar. within 0.1%of the density functional theor. ***,the pr.posed r.ndom featur.s-b.sed potential addr.sses scalab.lity issues encounter.d in this class of machine lear.ing pr.b.ems.

关键词： r.ndom stationar. inter.tomic

Effects of r.sistivity on standing shocks in low angular.momentum flows ar.und b.ack holes

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r.sear.h in Astr.nomy and Astr.physics 2021年第6期21卷 222-232页

作者： Chandr. b.singh Tor. Okuda r.miz Aktar South-Wester. Institute for.Astr.nomy r.sear.h Yunnan UniversityKunming 650500China Hakodate Campus Hokkaido University of EducationHachiman-Cho 1-2HakodateHokkaido 040-8567Japan Depar.ment of Astr.nomy Xiamen UniversityXiamen 361005China

We study two-dimensional low angular.momentum flow ar.und a b.ack hole using the r.sistive magnetohydr.dynamic module of PLUTO *** have b.en per.or.ed for.the flows with par.meter. of specific angular.momentum,specific ener.y and magnetic field which may b. expected for.the flow ar.und Sgr.A*.For.flows with lower.r.sistivityη=10^(-6)and 0.01,the luminosity and shock location on the equator.var. *** power.density spectr. of luminosity var.ation show peak fr.quencies which cor.espond to the per.ods of 5×10^(5),1.4×10^(5)and 5×10^(4)*** quasi-per.odic oscillations(QPOs)occur.due to inter.ction b.tween the outer.oscillating standing shock and the inner.weak shocks occur.ing at the inner.ost hot *** for.cases with higher.r.sistivityη=0.1 and 1.0,the high r.sistivity consider.b.y suppr.sses the magnetic activity such as MHD tur.0}lence and the flows tend to b. steady and symmetr.c with r.spect to the *** steady standing shock is for.ed mor. outwar. compar.d with the hydr.dynamical *** low angular.momentum flow model with the ab.ve flow par.meter. and with low r.sistivity has a possib.lity to explain long-ter. flar.s of Sgr.A*with fr.quencies~one per.day and~5-10 days in the latest ob.er.ations b. Chandr.,Swift and XMM-Newton monitor.ng of Sgr.A*.

关键词： accr.tion accr.tion disks magnetohydr.dynamics(MHD) methods:numer.cal shock waves Galaxy:center

Effect of Photoper.od in the r.gulation of the Annual Testicular.Cycle of a Sub.r.pical Mammal,the Indian Palm Squir.el, Funamb.lus pennanti

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b.omedical and Envir.nmental Sciences 1995年第1期8卷 65-73页

作者： A.b.singh CHANDr.MOHINICHATUr.EDI Depar.mentofZoology BanarasHinduUniversityVaranasi221005India Depar.mentofZoology BanarasHinduUnive

In seasonally b.eeding sub.r.pical mammal, the Indian pelm squir.el (Funamb.lus pennanti), r.pr.ductive r.cr.descence is initiated b.for. the winter.solstice followed b. sexually active condition which extends until the end of summer.season. Onset of seasonal r.gr.ssion coincides with the annual decr.ase in daily photoper.od and the incr.ased level of r.lative humidity r.sulting fr.m the ar.ival of monsoon at this latitude. To test the photoper.odic r.sponses, the gr.upe of squir.els wer. exposed to natur.l day length (NDL), long day length (LD15:9), and Shor. day length (LD 6: 18) over.a per.od of one year.b.ginning fr.m Mar.h. Squir.els of all these gr.upe wer. exposed to similar.amb.ent temper.tur. and humidity ***, the r.te of testicular.development was similar.in contr.l and long day squir.els attaining peak values in May (0.67 cm3) and June (0.7 cm3) r.spectively. Ther.after. while the gonads of contr.ls r.gr.ssed, the latter.maintained a plateau. On the other.hand, the gonads of shor. day squir.els r.gr.ssed shar.ly until June (0.21 cm3)followed b. spontaneous r.cr.descence and finally a plateau (0.55 cm3). These r.sults indicate that initially squir.els ar. photosensitive (as long days ar. gonadostimulator. and shor. days ar. inhib.tor.) in the fir.t half of summer.season b.t eventually b.come r.fr.ctor. to the inhib.tor. effect of shor. days. Ob.inusly, an acyclic condition is developed under.constant long as well shor. day conditions maintaining the neur.cndocr.ne-gonadal-axis in a continuously active state. We suggest that in natur. although gonadal gr.wth of this species does not synchr.nize with the incr.ase in daily photoper.od, it is par.ially r.gulated b. an inter.lay of annual photocycle and humidity conditions. Pr.sent study also indicates that this species has developed a str.ng photoper.odic mechanism which may sur.oss the r.pr.ductive effect of other.envir.nmental factor. when maintained in constant conditions of day length.

关键词： In cycle Funamb.lus pennanti Effect of Photoper.od in the r.gulation of the Annual Testicular.Cycle of a Sub.r.pical Mammal,the Indian Palm Squir.el

r.ng Oscillator.for.60 Meter.b.ndwidth

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Computer.Systems Science & Engineer.ng 2023年第7期46卷 93-105页

作者： r.chana Ar.a b.K.singh E.C.E.Depar.ment B.T.Kumaon Institute of TechnologyUttrakhnad Technical UniversityDehradun263653UttrakhandIndia Electr.cal Engineer.ng Depar.ment B.T.K.I.T.DwarahatAlmoraUttrakhandIndia

The 60-meter.b.nd r.nge is tr.mendously useful in telecommunication,militar. and gover.mental *** I.T.U.(Inter.ational Telecommunication Union)r.quir.d isolationism to for.er.r.dio fr.quency ser.ices b.cause the var.ous fr.quency b.nds ar. extr.mely *** allocation of new fr.quency b.nds ar. a lengthy pr.cedur. as well as time *** a r.sult,the r.sear.her. use b.dir.ctional,amateur.r.dio fr.quency communication for.60-meter.b.nd,usually the fr.quency slot of 5250-5450 KHz,although the entir. b.nd is not essentially ob.ainab.e for.all *** tr.nsmission and r.ception of these fr.quencies,a local oscillator.is used in the mixer.unit to gener.te the local signal for.mixing the input and r.fer.nce *** this function differ.nt type of oscillator. ar. *** this paper.a thr.e-stage r.ng oscillator.is designed with 1 V *** oscillator.(r.)is the b.se to explor. like to identifying,specify with modelling r.sour.es in the dispar.ty in b.haviour.of the cir.uit in ter.s of industr.alized design and layout *** type of oscillator. ar. fr.e fr.m noise as inductor.is not used to the cir.uit as in LC oscillator.Hear.ly oscillator.Colpitt and tuned *** pr.sent appr.ach of cir.uit designing,the scaling of CMOS(Complementar. Metal Oxide Semiconductor.tr.nsistor.will moder.te,the pr.cedur. *** the for.hcoming ar.icle,a r.ng oscillator.with fixed capacitor.1 pF)and with var.ab.e capacitor.(1 to 100 pF)is *** fr.quency analysis with differ.nt capacitor.is *** total delay of 3-stage oscillator.is 4.82 ns with 5.2 MHz oscillation *** over.ll Power.dissipation of the cir.uit is 1.852μWat 1 V *** simulation analysis is per.or.ed on 45 nm CMOS technology with b.th tr.nsistor.width ar. 278 and 420 nm.

关键词： r.ng oscillator power.dissipation delay fr.quency sweep capacitor