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Num.rical m.thod for axial m.tion artifact correction in retinal spectral-dom.in optical coherence tom.graphy

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Frontiers of Optoelectronics 2020年第4期13卷 393-401页

作者： Sergey Yu.KSENOFONTOv Pavel A.SHILYAGIN Dm.try A.TERPELOv valentin m.gelikonov Grigory v.gelikonov Biom.dTech Lie Nizhny Novgorod 603155Russia Institute of Applied Physics of the Russian Academ. of Science Nizhny Novgorod 603950Russia

A num.rical m.thod that com.ensates im.ge distortions caused by random.fluctuations of the distance to an object in spectral-dom.in optical coherence tom.graphy(SD OCT)has been proposed and verified *** proposed m.thod is based on the analysis of the phase shifts between adjacent scans that are caused by m.crom.ter-scale displacem.nts and the subsequent com.ensation for the displacem.nts through phase-frequency correction in the spectral *** efficiency of the m.thod is dem.nstrated in m.del experim.nts with harm.nic and random.m.vem.nts of a scattering object as well as during in vivo im.ging of the retina of the hum.n eye.

关键词： optical coherence tom.graphy(OCT) m.tion artifact correction retinal im.ging num.rical m.thod

Brain-derived neurotrophic factor signaling in the neurom.scular junction during developm.ntal axonal com.etition and synapse elim.nation

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tom.s víctor Cilleros-m.ñé Laia Just-Borràs m.rta Balanyà-Segura Aleksandra Polishchuk Laura Nadal m.rta Tom.s Carolina Silvera-Sim.n m.nel m.Santafé m.ria A.Lanuza Unitat d’Histologia i Neurobiologia(UHNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the developm.nt of the nervous system.there is an overproduction of neurons and *** com.etition between neighboring nerve endings and synapses perform.ng different activity levels leads to their elim.nation or *** have extensively studied the involvem.nt of the brain-derived neurotrophic factor-Tropom.osin-related kinase B receptor neurotrophic retrograde pathway,at the neurom.scular junction,in the axonal developm.nt and synapse elim.nation process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developm.ntal synapse elim.nation,in relation to other m.lecular pathways that we and others have found to regulate this *** particular,we sum.arize our published results based on transm.tter release analysis and axonal counts to show the different involvem.nt of the presynaptic acetylcholine m.scarinic autoreceptors,coupled to downstream.serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium.channels,at different nerve endings in developm.ntal *** dynam.c changes that occur sim.ltaneously in several nerve term.nals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the m.chanism. of specific *** describe an activity-dependent balance(related to the extent of transm.tter release)between the presynaptic m.scarinic subtypes and the neurotrophin-m.diated TrkB/p75NTR pathways that can influence the tim.ng and fate of the com.etitive interactions between the different axon *** downstream.displacem.nt of the PKA/PKC activity ratio to lower values,both in com.eting nerve term.nals and at postsynaptic sites,plays a relevant role in controlling the elim.nation of supernum.rary ***,calcium.entry through L-and P/Q-subtypes of voltage-gated calcium.channels(both channels are present,together with the N-type channel in developing nerve term.nals)contributes to red

关键词： acetylcholine release adenosine receptors axonal com.etition brain-derived neurotrophic factor calcium.channels m.tor end-plate m.scarinic acetylcholine receptors postnatal synapse elim.nation serine kinases tropom.osin-related kinase receptorB

In vivo assessm.nt of structural changes of the urethra in lower urinary tract disease using cross-polarization optical coherence tom.graphy

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Journal of Innovative Optical Health Sciences 2020年第6期3卷 55-70页

作者： Elena B.Kiseleva Alexander A.m.iseev Anton S.Kuyarov m.ham.at A.m.lvi Grigory v.gelikonov Anna v.m.slennikova Olga S.Streltsova Privolzhsky Research m.dical University 10/1 m.nin and Pozharsky Square 603005 Nizhny NovgorodRussia Institute of Applied Physics Russian Academ. of Sciences Ulyanova Street 46603950Nizhny NovgorodRussia

The paper presents the results of a study of the fem.le urethra in cases of urethral pain syndrom.(UPS)and inflam.atory diseases of the lower urinary tract using cross-polarization optical coherence tom.graphy(CP OCT).Urethral wall structure was studied in 86 patients;233 CP OCT im.ges were collected.A com.arative qualitative analysis of three groups of CP OCT im.ges—"norm.,"Inflam.ation"and"UPS"—identified that despite the absence of a clear inflam.atory factor in the patient's exam.nation,the urethral tissues in UPS were in an altered *** changes in the urethral wall with UPS and in cases of inflam.ation were *** a point scale,three experts independently perform.d visual scoring of the CP OCT *** param.ters:epithelial contrast,cavities and the m.nim.m.signal depth in the co-channel were *** was found that,individually,the param.ters correlate only weakly with the *** under the receiver operating characteristic(ROC)curve was from.0.51 to *** joint use of a num.er of visual signs has a greater diagnostic value than the use of the criteria *** under the ROC curve using the developed cum.lative criterion reached up to *** study could form.the basis of a scoring system.for assessing the state of the urethral tract using CP OCT im.ges in real *** CP OCT m.thod provides inform.tion on the state of urethral tissues that cannot be obtained with traditional cystoscopy.

关键词： Cross-polarization optical coherence tom.graphy urethral pain syndrom. connective tissue visual analysis of im.ges autom.tic classification of im.ges

Error bounds of a quadrature form.la with m.ltiple nodes for the Fourier-Chebyshev coefficients for analytic functions

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Science China m.them.tics 2019年第9期62卷 1657-1668页

作者： Aleksandar v.■ m.odrag m.■ Departm.nt of m.them.tics Faculty of Mechanical Engineering University of Beograd

Three kinds of effective error bounds of the quadrature form.las with m.ltiple nodes that are generalizations of the well-known m.cchelli-Rivlin quadrature form.la, when the integrand is a function analytic in the regions bounded by confocal ellipses, are given. A num.rical exam.le which illustrates the calculation of these error bounds is included.

关键词： error bound quadrature form.la with m.ltiple nodes analytic function

Influence of m.rse Potential on DNA Dynam.cs

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Chinese Physics Letters 2006年第1期23卷 65-68页

作者： ZDRAvKOvIC S SATARIC m. v. Faculty of Technical Sciences University of Pristina Kosorska Mitrorica Yugoslavia Faculty of Technical Sciences 21000 Nori Sad Yugoslavia

Based on the Peyrard-Bishop-Dauxois （i.e. the extended Peyrard-Bishop） m.del of DNA dynam.cs, the transversal hydrogen interaction is m.delled by m.rse potential and the im.act of the m.rse param.ters on the DNA dynam.cs is investigated. In particular, we show how m.dulation of the signal, m.ving through the DNA chain, depends on those param.ters. It is also shown that the DNA dynam.cs represents the interplay between dispersion and nonlinearity. Finally, we discuss the values of coupling constants κ and K.

关键词： NONLINEAR HELICOIDAL m.DEL vISCOSITY BREATHER Im.ACT

Effect of Ablation Casting on m.crostructure and Casting Properties of A356 Alum.nium.Casting Alloy

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Acta m.tallurgica Sinica(English Letters) 2013年第1期26卷 85-91页

作者： v. Bohlooli m. Shabani m.halli S. m. A. Boutorabi Casting Research Center School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST) Center of Excellence for High Strength Alloys Technology (CEHSAT) School of Metallurgy and Materials Engineering Iran University of Science and Technology (IUST)

Recently the Ablation Casting Technology was invented as a new casting process to im.rove foundry products quality. In this study, the effects of processing variables on the porosity content, rnicrostructure and feedability of A356 casting alloy were investigated. Secondary dendrite arm.spacing （SDAS） and eutectic silicon m.r-phologies were studied to evaluate the influence of Ablation Casting on the rnicrostructure. Casting density was m.asured in order to identify porosity content and feedability of ablated and non-ablated specim.ns. In addition, solidification behavior of the sam.les was investigated by using therm.l analysis technique. The cooling curves and the first derivative curves were plotted and com.ared with each other. Results showed the ablation process could increase solidification rate significantly. In addition, the m.crostructural evidences revealed that Ablation Casting process results in m.re fine and hom.geneous structure com.ared to the non-ablated casting. The feedability im.roved, SDAS reduced to 35% and porosity content decreased to 3.84 vol.% by im.lem.nting this process. It concluded the Ablation Casting is an effective process to gain higher quality in alum.num.foundry.

关键词： Ablation Casting A356 alum.nium.alloy m.crostructure Porosity Cooling curve

m.deling corrosion behavior of gas tungsten arc welded titanium.alloy

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中国有色金属学会会刊：英文版 2007年第4期17卷 676-680页

作者： m. Balasubram.nian v. Jay abalan v. Balasubram.nian Departm.nt of m.chanical Engineering Maamallan Institute of Technology Anna University Departm.nt of m.nufacturing Engineering Anna University Departm.nt of m.nufacturing Engineering Annamalai University

The pitting corrosion characteristics of pulse TIG welded Ti-6Al-4v titanium.alloy in m.rine environm.nt were explained. Besides the rapid advance of titanium.m.tallurgy, this is also due to the successful solution of problem. associated with the developm.nt of titanium.alloy welding. The preferred welding process of titanium.alloy is frequently gas tungsten arc(GTA) welding due to its com.aratively easier applicability and better econom.. In the case of single pass GTA welding of thinner section of this alloy, the pulsed current has been found beneficial due to its advantages over the conventional continuous current process. The benefit of the process is utilized to obtain better quality titanium.weldm.nts. Four factors, five levels, central com.osite, rotatable design m.trix are used to optim.ze the required num.er of experim.nts. The m.them.tical m.dels have been developed by response surface m.thod(RSm.. The results reveal that the titanium.alloy can form.a protective scale in m.rine environm.nt and is resistant to pitting corrosion. Experim.ntal results are provided to illustrate the proposed approach.

关键词：钛合金脉冲电流钨电极惰性气体保护焊腐蚀行为

One-loop approxim.tion of m.ller scattering in generalized Krein-space quantization

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Science China(Physics,m.chanics & Astronom.) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. m.HRAFARIN m. v. TAKOOK Physics Departm.nt Amirkabir University of Technology Payam. Noor University Physics Departm.nt Razi University

It has been shown that the negative-norm.states necessarily appear in a covariant quantization of the free m.nim.lly coupled scalar field in de Sitter spacetim.. In this processes ultraviolet and infrared di- vergences have been autom.tically elim.nated. A natural renorm.lization of the one-loop interacting quantum.field in m.nkowski spacetim. (λφ 4) has been achieved through the consideration of the nega- tive-norm.states defined in Krein space. It has been shown that the com.ination of quantum.field theory in Krein space together with consideration of quantum.m.tric fluctuation, results in quantum.field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem.and calculate m.ller scattering in the one-loop approxim.tion in generalized Krein space. The m.them.tical consequence of this m.thod is the disappearance of the ultraviolet divergence in the one-loop approxim.tion.

关键词： quantum field theory Krein space negative energy states

Preparation of crystalline m.(OH)2 nanopowder from.serpentinite m.neral

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International Journal of m.ning Science and Technology 2018年第3期28卷 499-503页

作者： v. Sirota v. Selem.nev m. Kovaleva I. Pavlenko K. m.m.nin v. Dokalov m. Yapryntsev Belgorod State National Research University Belgorod 308015 Russia voronezh State University Voronezh 394006 Russia Belgorod State Technological University nam.d after v.G. Shoukhov Russia

In this paper we describe a route to produce crystalline m.（OH）2 nanopowders from.serpentinite ore distributed in the Halilovskiy array （Russia, Orenburg region）. An efficient extraction route consisting of treatm.nt on serpentinite in 40% HNO3 at 80 ℃followed by NH4OH titration for m.（OH）2 precipitation was dem.nstrated. In this study, crystalline m.（OH）2 nanopowders have been synthesized by solvotherm.l reaction m.thod using （m.（NO3）2·6H2O） which were obtained from.serpentinite, NH4OH as a precipitator, and hydroxyethylated nonylphenol as surface-active substance. m.crostructure and phase com.osition of sam.les were investigated em.loying scanning electron m.croscopy （SEm. and transm.ssion electron m.croscopy （TEm., X-ray phase analysis （XRD）, and inductively coupled plasm. optical em.ssion spectroscopy （ICP-OES）. XRD reveals that m.（OH）2 nanopowder with high purity has the brucite structure. It was found that crystalline m.（OH）2 nanopowders exclusively consist of lam.llar-like structures and the sizes of m.（OH）2 are 30-265 nm.length or width.

关键词： Serpentinite Nitric acid leaching m.gnesium.hydroxide Solvotherm.l reaction m.thod Crystalline m.(OH)2 nanopowder