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Cortical hem.signaling center: functions, developm.nt, and potential im.lications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.Chizhikov Igor y.Iskusny.h departm.nt of Anatom.0}and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

developm.nt of the telencephalon relies upon several signaling centers-localized cellular populations that supply.secreted factors to pattern the cortical *** such signaling center is the cortical hem.which arises during em.ry.nic developm.nt at the telencephalic dorsal m.dline,adjacent to the choroid plexus and hippocam.al prim.rdium.Figure 1A).While the cortical hem.has also been described in reptiles and birds,m.st of our knowledge about the developm.ntal roles of the cortical hem.is derived from.the analy.is in *** cortical hem.produces several ty.es of secreted m.lecules,including wingless-related integration site(Wnt)and bone m.rphogenetic(Bm.)*** cortical hem.is particularly.im.ortant for the developm.nt of the hippocam.us,which is involved in learning and m.m.ry.and the neocortex,which is the m.st com.lex brain region that m.diates m.ltiple ty.es of behavior and higher cognitive functions(m.ngale et al.,2008;dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Low tem.erature oxidation of Cr-alloy.d m.Si_2

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中国有色金属学会会刊：英文版 2007年第6期17卷 1282-1286页

作者： E. Strom.y. Cao y. m. y.o Kanthal AB Box 502 SE-734 27 Hallstahammar Sweden departm.nt of m.terials and m.nufacturing Technology Chalmers University Technology SE-412 96 Gothenburg Sweden

Cr-alloy.d m.Si2 was com.ared with m.nolithic m.Si2 with respect to oxidation at 450 ℃ for 456 h. Phases form.d on Cr-alloy.d m.Si2 after exposure are Cr2(m.O4)3, m.O3, and cristobalite (SiO2) according to X-ray.diffraction results. m.nolithic m.Si2 form. m.O3 and m.inly.am.rphous SiO2. X-ray.photoelectron spectroscopy.indicates that the m.in oxidation product on the outerm.st surface is SiO2 for all studied sam.les. The sam.les form.a relatively.loose oxide but the oxide adherence im.roves with increasing Cr content. It is indicated that Cr addition can benefit pesting control in m.Si2.

关键词：钼硅化合物合金有害物氧化作用

Regularity.of atom.c nuclei with random.interactions： sd bosons

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Frontiers of phy.ics 2018年第6期13卷 197-211页

作者： y. m. Zhao School of Phy.ics and Astronom. Shanghai Jiaotong University Shanghai 200240 China

Atom.c nuclei are com.lex sy.tem. with gigantic configuration spaces, therefore truncations of m.del spaces are indispensable. due to the short-range nature of the nuclear interactions, one m.y.resort to a truncation by.using coherent nucleon-pairs which are conveniently.further sim.lified as bosons, such as sd bosons. The discovery.of the spin-zero ground state dom.nance with random.two-body.interactions led to a series of studies on regular structure for sd bosons in the presence of random.interactions, and this review article sum.arizes studies along this line in last two decades. We concentrate on various patterns exhibited in sd boson sy.tem., and dem.nstrate that m.ny.random.sam.les which were thought to be noisy.exhibit very.regular patterns, som. of which are interpreted in term. of the V（5）, O（6）, O（6）, SU（3）, and SU（3） dy.am.cal sy.m.tries of the sd interacting boson m.del.

关键词： regularity random.interactions sd bosons

An electron m.ir■ m.thod for a com.on SEm

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Acta m.chanica Sinica 2006年第6期22卷 595-602页

作者： y. m. Xing S. Kishim.to y. R. Zhao departm.nt of Applied m.chanics Inner Mongolia University of Technology Hohhot 010051 China National Institute for m.terials Sciences Tsukuba Ibaraki 305-0047 Japan

In the electron m.iré m.thod, a high-frequency.grating is used to m.asure m.croscopic deform.tion, which prom.ses significant potential applications for the m.thod in the m.croscopic analy.is of m.terials. However, a special beam.scanning control device is required to produce a grating and generate a m.iré fringe pattern for the scanning electron m.croscope （SEm.. Because only.a few SEm. used in the m.terial science studies are equipped with this device, the use of the electron m.iré m.thod is lim.ted. In this study. an electron m.iré m.thod for a com.on SEm.without the beam.control device is presented. A grating based on a m.lti-scanning concept is fabricated in any.observing m.de. A real-tim. m.iré pattern can also be generated in the SEm.or an optical filtering sy.tem. Without the beam.control device being a prerequisite, the electron m.iré m.thod can be m.re widely.used. The experim.ntal results from.three different ty.es of SEm. show that high quality.gratings with uniform.lines and less pitch error can be fabricated by.this m.thod, and m.iré patterns can also be correctly.generated.

关键词： Electron m.iré Grating m.lti-scanning Electron beam.m.iré

ARTIFICIAL NEURAL NETWORK m.dEL OF CONSTITUTIVE RELATIONSHIP FOR 2A70 ALUm.NUm.ALLOy

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Acta m.tallurgica Sinica(English Letters) 2005年第6期18卷 719-723页

作者： F. Liu d.B. Shan y. Lu y. y. yang School of m.terials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The hat deform.tion behavior of 2A70 alum.num.alloy.was investigated by.m.ans of isotherm.l com.ression tests perform.d on a Gleeble-1500 therm.l sim.lator over a wide range of tem.eratures 360-480℃ with strain rates of 0.01-1s^-1 and the largest deform.tion of 60%, and the true stress of the m.terial was obtained under the above-m.ntioned conditions. The experim.ntal results shows that 2A70 alum.num.alloy.is a kind of alum.num.alloy.with the property.of dy.am.c recovery. its flow stress declines with the increase of tem.erature, while its flow stress increases with the increase of strain rates. On the basis of experim.nts, the constitutive relationship of the 2A70 alum.num.alloy.was constructed using a BP artificial neural network. Com.arison of the predicted values with the experim.ntal data shows that the relative error of the trained m.del is less than ±3% for the sam.led data while it is less than ±6% for the nonsam.led data. It is evident that the m.del constructed by.BP ANN can accurately.predict the flow stress of the 2A70 alloy.

关键词： 2A70 alum.num.alloy flow stress constitutive relationship,BP artificial neural network

Recent Advances in Com.utational Sim.lation of m.cro-,m.so-,and m.cro-Scale Biom.m.tics Related Fluid Flow Problem.

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Journal of Bionic Engineering 2007年第2期4卷 97-107页

作者： y. y. y.n School of the Built Environm.nt The University of Nottingham Nottingham NG7 2RD UK

Over the last decade, com.utational m.thods have been intensively.applied to a variety.of scientific researches and engineering designs. Although the com.utational fluid dy.am.cs （CFd） m.thod has play.d a dom.nant role in study.ng and sim.lating transport phenom.na involving fluid flow and heat and m.ss transfers, in recent y.ars, other num.rical m.thods for the sim.lations at m.so- and m.cro-scales have also been actively.applied to solve the phy.ics of com.lex flow and fluid-interface interactions. This paper presents a review of recent advances in m.lti-scale com.utational sim.lation of biom.m.tics related fluid flow problem.. The state-of-the-art num.rical techniques, such as lattice Boltzm.nn m.thod （LBm., m.lecular dy.am.cs （m.）, and conventional CFd, applied to different problem. such as fish flow, electro-osm.sis effect of earthworm.m.tion, and self-cleaning hy.rophobic surface, and the num.rical approaches are introduced. The new challenging of m.delling biom.m.tics problem. in developing the phy.ical conditions of self-clean hy.rophobic surfaces is discussed.

关键词： biom.m.tics com.utational sim.lation m.cro- m.so- m.cro-scale hy.rophobic surfaces

Quantified evaluation of particle shape effects from.m.cro-to-m.cro scales for non-convex grains

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Particuology 2016年第2期14卷 23-35页

作者： y. yang J.F. Wang y.m. Cheng departm.nt of Civil and Environm.ntal Engineering The Hong Kong Polytechnic University Hong Kong China departm.nt of Civil and Architectural Engineering City University of Hong Kong Hong Kong China

Particle shape play. an im.ortant role in both the m.cro and m.cro scales responses of a granular assem. bly. This paper presents a sy.tem.tic way.to interpret the shape effects of granular m.terial during quasi-static shearing. A m.re suitable shape descriptor is suggested for the quantitative analy.is of the m.croscale strength indexes and contact param.ters for non-convex grains, with special consid- eration given to the peak state and critical state. Through a series of num.rical sim.lations and related post-processing analy.is, particle shape is found to directly.influence the strain localisation patterns, m.croscale fabric distributions, m.croscale m.bilisation indexes, and probability.distribution of the nor- m.lised contact norm.l force. Additionally. the accuracy.of the stress-force-fabric relationship can be influenced by.the average norm.l force and the distribution of contact vectors. m.reover, particle shape play. a m.re im.ortant role than do the confining pressures in determ.ning the friction angle. Strong force chains and the dilation effect are also found to be strongly.influenced by.the high confinin~ oressure.

关键词： Quantitative analy.is Shape factor Statistical analy.is m.cro-m.cro indexes

THEORy.OF WATER WAVES IN AN ELASTIC VESSEL

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Acta m.chanica Sinica 2000年第2期16卷 97-112页

作者： d. y. Hsieh division of Applied m.them.tics Brown University USA

Recent experim.nts related to the dragon Wash phenom.na showed that axisy.m.tric capillary.waves appear first from.excitation, and circum.erential capillary.waves appear after increase of the excitation strength. Based on this new finding, a theory.of param.tric resonance is developed in detail to explain the on- set of the prom.nent circum.erential capillary.waves. Num.rical com.utation is also carried out and the results agree generally.with the experim.nts. Analy.is and nu- m.rical com.utation are also presented to explain the generation of axisy.m.tric low-frequency.gravity.waves by.tile high-frequency.external excitation.

关键词： water waves elastic vessel dragon Wash

Phy.ical m.chanism.for origin of stream.ise vortices in m.de A of a square-section cy.inder

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Acta m.chanica Sinica 2019年第2期35卷 411-418页

作者： L. m. Lin S. y. Shi y. X. Wu Key.Laboratory.for m.chanics in Fluid Solid Coupling Sy.tem. Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China School of Engineering Sciences University of Chinese Academy of Sciences Beijing 100049 China

In the present paper, phy.ical m.chanism.responsible for origin of stream.ise vortices in m.de A appeared in the threedim.nsional (3-d) wake transition of a square-section cy.inder is investigated. direct num.rical sim.lations at a Rey.olds num.er of 180 firstly.show that such stream.ise vorticity.is not originated from.lateral surfaces. Then through the analy.is of local flow field in the im.ediate neighborhood of rear surface, based on the theory.of vortex-induced vortex, a new phy.ical m.chanism.is identified. At first, the vertical vorticity.on rear surface is generated by.the intrinsic three-dim.nsional instability.with the sam. instability.wavelength of m.de A. Then the stream.ise vorticity.at a specific sign is induced by.such vertical vorticity. convected and concentrated in the shear lay.rs. Finally. stream.ise vortices are form.d and shed with alternatively.shedding spanwise vortices in the near wake. m.reover, the effect of induced spanwise vorticity.on original two-dim.nsional (2-d) spanwise vorticity.is also presented in detail.

关键词： m.de A Stream.ise vortices Wake Square cy.inder Vortex-induced vortex