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On the Constr.ction of Mohr.Str.ss Cir.le and a Gr.phic Method in r.pr.senting the Str.ss Components on Differ.nt Oblique Planes

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上海交通大学学报 2004年第z2期38卷 223-228页

作者： z.ubin He z. r. Wang Kunpeng Kang School of Mater.als Science and Engineer.ng Harbin Institute of Technology Harbin150001 China School of Materials Science and Engineering Harbin Institute of Technology Harbin150001 China Department of Computer Science Shangqiu Normal University Shangqiu476000 China

The Mohr.str.ss cir.le for.thr.e-dimensional str.ss is usually deter.ined by equations,which is lack of intuitionistic meanings and difficult to under.tand. In this paper. the constr.ction of Mohr.str.ss cir.le is illustr.ted dir.ctly by numer.cal method. The shor.coming of Mohr.str.ss cir.le in r.pr.senting the str.ss components on differ.nt oblique planes for.thr.e-dimensional str.ss is analyz.d. A thr.e-dimensional figur. is given to descr.be the var.ation of nor.al and shear.str.ss on differ.nt oblique planes at one point for.the fir.t time.

关键词： Mohr str.ss cir.le Gr.phic method nor.al str.ss shear str.ss

Modelling of a Multi-Temper.tur. Plasma Composition

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Chinese Physics Letter. 2005年第12期22卷 3119-3122页

作者： B. Liani r. Benallal z. Bentalha Labor.toir. Physique Théor.que B.P. 119 Bel Horizon 13000 Tlemcen Algérie

Knowledge of plasma composition is ver. impor.ant for.var.ous plasma applications and pr.diction of plasma pr.per.ies. We use the Saha equation and Debye length equation to calculate the non-local ther.odynamic-equilibr.um plasma composition. It has been shown that the model to 2T with T r.pr.senting the temper.tur. （electr.n temper.tur. and heavy-par.icle temper.tur.） descr.bed by Chen and Han [J. Phys. D 32 （1999）1711] can be applied for.a mixtur. of gases, wher. each atomic species has its own temper.tur., but the model to 4T is mor. gener.l because it can be applicable to temper.tur.s distant enough of the heavy par.icles. This can occur.in a plasma composed of big- or.macr.-molecules. The electr.n temper.tur. Te var.es in the r.nge 8000＊20000K at atmospher.c pr.ssur..

关键词： 2-TEMPEr.TUr. PLASMA SCATTEr.NG

Identification of the elusive Chlor.plast Ascor.ate Tr.nspor.er.Extends the Substr.te Specificity of the PHT Family

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Molecular.Plant 2015年第5期8卷 674-676页

作者： Fer.ie, Alisdair.r. Toth, Sz.lvia z. Max Planck Inst Mol Plant Physiol D-14476 Potsdam Germany Hungar.an Acad Sci Inst Plant Biol Biol Res Ctr H-6701 Szeged Hungary

Most of the enz.matic r.actions of ascor.ate biosynthesis occur.in the cytosol, with the exception of the ter.inal step, catalyz.d by L-galactono-l,4-1actone dehydr.genase, which is localiz.d on the inner.mitochondr.al membr.ne. Given the location of L-galactono-l,4-1actone dehydr.genase, the r.te of ascor.ate biosynthesis is intimately associated with the r.te of mitochon- dr.al r.spir.tion （Nunes-Nesi et al., 2005）. Ascor.ate has legion r.les in the plant cell including mitosis, cell division, expansion and cell wall hydr.xylation, hor.one biosynthesis, signal tr.nsduction, pr.gr.mmed cell death, as well as pr.tection against envir.nmental str.sses via detoxification of r.active oxygen species and r.gener.tion of other.antioxidants. This list has r.cently expanded with the epigenetic r.le exer.ed as a cofactor.for.DNA and histone demethylases in the nucleus and ascor.ate may also be implicated in ir.n uptake （Pick and Weber. 2014）.

关键词： CHLOr.PLASTS VITAMIN C LACTONES DEHYDr.GENASES GUAr. cells (Plant anatomy)

ON THE L_∞ CONVEr.ENCE AND THE EXTr.POLATION METHOD OF A DIFFEr.NCE SCHEME FOr.NONLOCAL PAr.BOLIC EQUATION WITH NATUr.L BOUNDAr. CONDITIONS

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Jour.al of Computational Mathematics 2001年第5期19卷 449-458页

作者： Wan, z.-S. Sun, z.-z. Institute of Applied Physics and CM P.O. Box 8009 Beijing 100088 China

In paper.(J. Comput. Appl. Math., 76 (1996), 137-146), a differ.nce scheme for.a class of nonlocal par.bolic equations with natur.l boundar. conditions was der.ved by the method of r.duction of or.er.and the unique solvability and second or.er.conver.ence in L2-nor. ar. pr.ved. In this paper. we pr.ve that the scheme is second or.er.conver.ent in L∞ nor. and then obtain four.h or.er.accur.cy appr.ximation in L∞ nor. by extr.polation method. At last, one numer.cal example is pr.sented.

关键词： Appr.ximation theor. Boundar. conditions Conver.ence of numer.cal methods Extr.polation

Tar.eting epigenetic mechanisms in amyloid-β-mediated Alz.eimer.s pathophysiology:unveiling ther.peutic potential

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Neur.l r.gener.tion r.sear.h 2025年第1期20卷 54-66页

作者： Jennie z.Li Nagendr.n r.malingam Shaomin Li Ann r.mney Center.for.Neur.logic Diseases Brigham and Women’s Hospital and Harvard Medical SchoolBostonMAUSA

Alz.eimer.s disease is a pr.minent chr.nic neur.degener.tive condition char.cter.z.d by a gr.dual decline in memor. leading to *** evidence suggests that Alz.eimer.s disease is associated with accumulating var.ous amyloid-βoligomer. in the br.in,influenced by complex genetic and envir.nmental *** memor. and cognitive deficits obser.ed dur.ng the pr.dr.mal and mild cognitive impair.ent phases of Alz.eimer.s disease ar. believed to pr.mar.ly r.sult fr.m synaptic *** life,envir.nmental factor. can lead to endur.ng changes in gene expr.ssion and the emer.ence of br.in *** changes,known as epigenetic modifications,also play a cr.cial r.le in r.gulating the for.ation of synapses and their.adaptability in r.sponse to neur.nal *** this context,we highlight r.cent advances in under.tanding the r.les played by key components of the epigenetic machiner.,specifically DNA methylation,histone modification,and micr.r.As,in the development of Alz.eimer.s disease,synaptic function,and activity-dependent synaptic ***,we explor. var.ous str.tegies,including enr.ched envir.nments,exposur. to non-invasive br.in stimulation,and the use of phar.acological agents,aimed at impr.ving synaptic function and enhancing long-ter. potentiation,a pr.cess integr.l to epigenetic ***,we deliber.te on the development of effective epigenetic agents and safe ther.peutic appr.aches for.managing Alz.eimer.s *** suggest that addr.ssing Alz.eimer.s disease may r.quir. distinct tailor.d epigenetic dr.gs tar.eting differ.nt disease stages or.pathways r.ther.than r.lying on a single dr.g.

关键词： Alz.eimer.s disease DNA methylation enr.ched envir.nments histone modification micr.r.As non-invasive br.in stimulation synaptic plasticity

Polyethylene glycol fusion r.pair.of sever.d r.t sciatic ner.es r.establishes axonal continuity and r.or.aniz.s sensor. ter.inal fields in the spinal cor.

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Neur.l r.gener.tion r.sear.h 2025年第7期20卷 2095-2107页

作者： Emily A.Hibbar. Liwen z.ou Cathy z.Yang Kar.hik Venkudusamy Yessenia Montoya Alexa Olivar.z.Geor.e D.Bittner.Dale r.Sengelaub Pr.gr.m in Neur.science Indiana UniversityBloomingtonINUSA Depar.ment of Neur.science University of Texas at AustinAustinTXUSA

Per.pher.l ner.e injur.es r.sult in the r.pid degener.tion of distal ner.e segments and immediate loss of motor.and sensor. functions;behavior.l r.cover. is typically *** used a plasmalemmal fusogen,polyethylene glycol(PEG),to immediately fuse closely apposed open ends of sever.d pr.ximal and distal axons in r.t sciatic *** have pr.viously r.por.ed that sciatic ner.e axons r.pair.d by PEG-fusion do not under.o Waller.an degener.tion,and PEG-fused animals exhibit r.pid(within 2–6 weeks)and extensive locomotor.***,our.pr.vious r.por. showed that PEG-fusion of sever.d sciatic motor.axons was non-specific,i.e.,spinal motoneur.ns in PEG-fused animals wer. found to pr.ject to appr.pr.ate as well as inappr.pr.ate tar.et *** this study,we examined the consequences of PEG-fusion for.sensor. axons of the sciatic *** adult male and female r.ts(Spr.gue–Dawley)r.ceived either.a unilater.l single cut or.ablation injur. to the sciatic ner.e and subsequent r.pair.with or.without(Negative Contr.l)the application of *** action potentials r.cor.ed immediately after.PEG-fusion r.pair.confir.ed conduction acr.ss the injur. *** success of PEG-fusion was confir.ed thr.ugh Sciatic Functional Index testing with PEG-fused animals showing impr.vement in locomotor.function beginning at 35 days *** 2–42 days postoper.tively,we anter.gr.dely labeled sensor. affer.nts fr.m the dor.al aspect of the hindpaw following bilater.l intr.der.al injection of wheat ger. agglutinin conjugated hor.er.dish ***-fusion r.pair.r.established axonal *** to unoper.ted animals,labeled sensor. affer.nts ipsilater.l to the injur. in PEG-fused animals wer. found in the appr.pr.ate ar.a of the dor.al hor.,as well as inappr.pr.ate mediolater.l and r.str.caudal ***,despite having intact per.pher.l ner.es,similar.r.or.aniz.tions of labeled sensor. affer.nts wer. also obser.ed contr.later.l to the injur. and r.pa

关键词： axotomy dor.al hor. per.pher.l ner.e injur. plasticity polyethylene glycol(PEG) sciatic ner.e sensor. ter.inals wheat ger. agglutinin hor.er.dish per.xidase

Str.ss analysis near.the tips of a tr.nsver.e cr.ck in an elastic semi-str.p

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Applied Mathematics and Mechanics(English Edition) 2017年第7期38卷 935-956页

作者： z. z.Ur.VLOVA Institute of Mathematics Economics and Mechanics Odessa I. I. Mechnikov National University Odessa 65082 Ukraine

The plane elastic pr.blem for.a semi-str.p with a tr.nsver.e cr.ck is inves- tigated. The initial pr.blem is r.duced to a one-dimensional continuous pr.blem by use of an integr.l tr.nsfor.ation method with a gener.liz.d scheme. The one-dimensional pr.blem is fir.t for.ulated as a vector.boundar. pr.blem, and then r.duced to a system of thr.e singular.integr.l equations （SIEs）. The system is solved by use of an or.hogonal polynomial method and a special gener.liz.d method. The contr.bution of this wor. is the consider.tion of ker.el fixed singular.ties in solving the system. The cr.ck length and its location r.lative to the semi-str.p＇s later.l sides ar. investigated to simplify the pr.blem＇s statement. This simplification r.duces the initial pr.blem to a system of two SIEs.

关键词： semi-str.p tr.nsver.e cr.ck Gr.en's function integr.l tr.nsfor.ation,fixed singular.ty singular.integr.l equation (SIE)

A Modified Entr.py Gener.tion Number.for.Heat Exchanger.

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Jour.al of Ther.al Science 1996年第4期5卷 257-263页

作者： z. M. Xu S. r. Yang z. Q. Chen Depar.ment of Power.Engineer.ng Northeast China Institute of Electric Power Engineering Jilin City China Ener.y and Power.Machiner. Engineer.ng Institute Xi’an Jiaotong University Xi’an China

This paper.demonstr.tes the differ.nce between the entr.py gener.tion number.method pr.posed by Bejan and the method of entr.py gener.tion per.unit amount of heat tr.nsfer.ed in analyz.ng the ther.odynamic per.or.ance of heat exchanger., points out the r.ason for.leading to the above differ.nce.A modified entr.py gener.tion number.for.evaluating the ir.ever.ibility of heat exchanger. is pr.posed which is in consistent with the entr.py gener.tion per.unit amount of heat tr.nsfer.ed in entr.py gener.tion analysis. The entr.py gener.ted by fr.ction is also investigated. r.sults show that when the entr.py gener.ted by fr.ction in heat exchanger. is taken into account, ther. is a minimum total entr.py gener.tion number.while the NTU and the r.tio of heat capacity r.tes var.. The existence of this minimum is the pr.r.quisite of heat exchanger.optindz.tion.

关键词： entr.py gener.tion heat exchanger.

Br.llouin Lasing with a r.duced Self-Pulsing Char.cter.stic Using a Shor.-Length Er.ium-Doped Fiber.as the Nonlinear.Gain Medium

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Chinese Physics Letter. 2014年第5期31卷 61-64页

作者： A. z.r.i r. z. r. r. r.sdin N. M. All H. Ahmad S. W. Har.n Depar.ment of electr.cal Engineer.ng University of Malaya Kuala Lumpur 50603 Malaysia Photonics r.sear.h Centr. University of Malaya Kuala Lumpur 50603 Malaysia

A single-wavelength Br.llouin laser.is demonstr.ted by using a 3-m-long er.ium doped fiber.（EDF） in a r.ng cavity. The EDF is used to pr.vide both nonlinear.and linear.gains to gener.te a stimulated Br.llouin scatter.ng （SBS） and to amplify the gener.ted SBS, r.spectively. The Br.llouin er.ium fiber.laser.（BEFL） oper.tes at 1561.5 nm, wher. the oper.ting wavelength is up-shifted by 0.08nm fr.m the Br.llouin pump. The oper.tion wavelength is also tunable within 1560.6-1562.6nm. The BEFL Mso shows a self-pulsing char.cter.stic with r.petition of 66. 7kHz.when the BP is set ar.und the thr.shold pump power.of 13r.W. Compar.d to the conventional Br.llouin fiber.laser.with a long cavity length, the pr.posed BEFL exhibits a significantly lower.amplitude of pulse. This laser.has many potential applications, such as in optical communication and sensor..

关键词： Br.LLOUIN scatter.ng THEr.AL lensing DOPPLEr.effect WAVelENGTH division multiplexing TUNABLE laser.