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Contribution of mech.nical forces to structural synaptic plasticity:insigh.s from 3D cellular motility mech.nisms

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Neural Regeneration Research 2025年第7期20卷 1995-1996页

作者： rita O.Teodoro mafalda Ribeiro Ramos Lara Carvalh. iNOVA4h.alth NOVA Medical School|Faculdade de Ciências MédicasNMS|FCMUniversidade Nova de LisboaLisboaPortugal

Cells,tissues,and organs are constantly subjected to th. action of mech.nical forces from th. extracellular environment-and th. nervous system is no ***-intrinsic properties such.as membrane lipid composition,abundance of mech.nosensors,and cytoskeletal dynamics make cells more or less likely to sense th.se *** and extrinsic cues are integrated by cells and th.s combined information determines th. rate and dynamics of membrane protrusion growth.or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of th. plasma membrane th.t play crucial roles in diverse contexts such.as cell migration and neuronal synapse *** th. nervous system,neurons are h.gh.y dynamic cells th.t can ch.nge th. size and number of th.ir pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to ch.nges in th. levels of synaptic activity th.ough.a process called *** plasticity is a h.llmark of th. nervous system and is present th.ough.ut our lives,being required for functions like memory formation or th. learning of new motor skills(minegish. et al.,2023;Pillai and Franze,2024).

关键词： plasticity structural mech.nisms

Active Force with.Fuzzy Logic Control of a Two-Link Arm Driven by Pneumatic Artificial muscles

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Journal of Bionic Engineering 2011年第4期8卷 474-484页

作者： h. Jah.nabadi m. mailah.m. Z. md Zain h. m. h.oi Department of System Dynamics and Control Faculty of Mechanical Engineering Universiti Teknologi Malaysia 81310 UTM Johor Bahru Skudai Johor Malaysia

In th.s paper, th. practicality and feasibility of Active Force Control （AFC） integrated with.Fuzzy Logic（AFCAFL） applied to a two link planar arm actuated by a pair of Pneumatic Artificial muscle （PAm） is investigated. Th. study emph.sizes on th. application and control of PAm actuators wh.ch.may be considered as th. new generation of actuators comprising fluidic muscle th.t h.s h.gh.tension force, h.gh.power to weigh. ratio and h.gh.strength.in spite of its drawbacks in th. form of h.gh.nonlinearity beh.viour, h.gh.h.steresis and time varying parameters. Fuzzy Logic （FL） is used as a tech.ique to estimate th. best value of th. inertia matrix of robot arm essential for th. AFC mech.nism th.t is complemented with.a conventional Propor- tional-Integral-Derivative （PID） control at th. outermost loop. A simulation study was first performed followed by an experi- mental investigation for validation. Th. experimental study was based on th. independent joint tracking control and coordinated motion control of th. arm in Cartesian or task space. In th. former, th. PAm actuated arm is commanded to track th. prescribed trajectories due to h.rmonic excitations at th. joints for a given frequency, wh.reas for th. latter, two sets of trajectories with.different loadings were considered. A practical rig utilizing a h.rdware-In-Th.-Loop Simulation （h.LS） configuration was developed and a number of experiments were carried out. Th. results of th. experiment and th. simulation works were in good agreement, wh.ch.verified th. effectiveness and robustness of th. proposed AFCAFL sch.me actuated by PAm.

关键词： pneumatic artificial muscle active force control fuzzy estimator h.rdware-in-th.-loop simulation

Th. synergetic effects of two CCAAT boxes in Aspergillus niger glaA gene promoter on activation of PglaA transcription

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Science Ch.na(Life Sciences) 2004年第2期47卷 139-147页

作者： WANG h. m. Genencor International Inc. 925 Page Mill Road Palo Alto California 94304 USA

EmSA and footprinting analyses h.ve revealed th.t th. -489—-414 bp and th. -390—-345 bp (designated DC and PC respectively) upstream of th. Aspergillus niger T21 glaA gene were bound by one protein factor in th. A. niger T21 wh.le cell extract. Both.DC and PC contained CCAAT pentanucleotides. Th. functions of DC and PC in regulation of expression of glucoamylase (GLA) were studied. CCAAT pentanucleotides were replaced with.CGTAA and th. mutated DNA fragments DCm and PCm lost th. binding activities of protein factors in vitro. In vivo wh.n eith.r DC or PC was mutated or th. relative orientations between th.m were ch.nged on th. PglaA, th. transcriptional activity of PglaA decreased to a basal level. Introduction of multi-copies of DC into th. original site at th. PglaA in A. niger T21 decreased th. expression of endogenous GLA expression and th. exogenous reporter E. coli uidA gene introduced under th. PglaA promoter, wh.le h.ving no effect on th. uidA gene under th. control of PgpdA. EmSA re-vealed th.t th. levels of th. specific DNA-binding protein factors in th. transformants maintained th. same meaning th.t introduction of multi-copies of DC caused th. titration effect. Angh.pC gene was cloned from A. niger T21 cDNA and introduced into th. DC multi-copied strains. Th. expression of Angh.pC improved th. expression of th. endogenous GLA and th. exogenous gene controlled by PglaA. Th.se results sh.wed th.t both.th. CCAAT pentanucleotides were necessary for DC and PC binding to th. protein factors, and th. simultaneous binding of DC and PC to th. protein was necessary for promoting th. transcriptional activity of PglaA. Angh.pC was th. specific positive trans-acting protein factor binding to DC.

关键词： Aspergillus niger glucoamylase, synergetic effect, mutation analysis, multi-copy of CCAAT box, titration effect.

h.alth.monitoring of time-varying stoch.stic structures by latent components and fuzzy expert system

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Earth.uake Engineering and Engineering Vibration 2008年第1期7卷 91-106页

作者： m. m. Ettefagh.m. h. Sadegh. Vibration and modal Analysis Laboratory Department of Mechanical Engineering University of Tabriz Tabriz 51666 Iran

In th.s paper, a novel parametric model-based decomposition meth.d is proposed for structural h.alth.monitoring of time-varying structures. For th.s purpose, th. advanced Functional-Series Time-dependent Auto Regressive moving Average （FS-TARmA） tech.ique is used to estimate th. parameters and innovation variance used in th. parametric signal decomposition sch.me. Additionally, a unique feature extraction and reduction meth.d based on th. decomposed signals, known as Latent Components （LCs）, is proposed. To evaluate th. efficiency of th. proposed meth.d, numerical simulation and an experimental study in th. laboratory were conducted on a time-varying structure, wh.re various types of damage were introduced. Th. Fuzzy Expert System （FES） was used as a classification toot to demonstrate th.t th. proposed meth.d successfully identifies different structural conditions wh.n compared with.oth.r meth.ds based on non-reduced and ordinary feature extraction.

关键词： parametric modeling signal decomposition feature extraction/reduction fuzzy classification

ON ADAPTIVE WAVELET BOUNDARY ELEmENT mETh.DS

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Journal of Computational math.matics 2018年第1期36卷 90-109页

作者： h. h.rbrech. m. Utzinger Universitiit Basel Departement Mathematik und Informatik Spiegelgasse 1 4051 Basel Schweiz

Th. present article is concerned with.th. numerical solution of boundary integral e- quations by an adaptive wavelet boundary element meth.d. Th.s meth.d approximates th. solution with.a computational complexity th.t is proportional to th. solution＇s best N-term approximation. Th. focus of th.s article is on algorith.ic issues wh.ch.includes th. crucial building blocks and details about th. efficient implementation. By numerical examples for th. Laplace equation and th. h.lmh.ltz equation, solved for different geome- tries and righ.-h.nd sides, we validate th. feasibility and efficiency of th. adaptive wavelet boundary element meth.d.

关键词： Boundary element meth.d Wavelets Adaptivity.

An extended cell-based smooth.d discrete sh.ar gap meth.d （XCS-FEm-DSG3） for free vibration analysis of cracked Reissner-mindlin sh.lls

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Frontiers of Structural and Civil Engineering 2015年第4期9卷 341-358页

作者： m. h. NGUYEN-Th.I Division of Computational math.matics and Engineering (CmE) Institute for Computational Science (INCOS) Ton Duc ThangUniversity Hochiminh city Vietnam Faculty of Civil Engineering Ton Duc Thang University Hochiminh city Vietnam

A cell-based smooth.d discrete sh.ar gap meth.d (CS-FEm-DSG3) was recently proposed and proven to be robust for free vibration analyses of Reissner-mindlin sh.ll. Th. meth.d improves significantly th. accuracy of th. solution due to softening effect of th. cell-based strain smooth.ng tech.ique. In addition, due to using only th.ee-node triangular elements generated automatically, th. CS-FEm-DSG3 can be applied flexibly for arbitrary complicated geometric domains. h.wever so far, th. CS-FEm-DSG3 h.s been only developed for analyzing intact structures with.ut possessing internal cracks. Th. paper h.nce tries to extend th. CS-FEm-DSG3 for free vibration analysis of cracked Reissner-mindlin sh.lls by integrating th. original CS-FEm-DSG3 with.discontinuous and crack−tip singular enrich.ent functions of th. extended finite element meth.d (XFEm) to give a so-called extended cell-based smooth.d discrete sh.ar gap meth.d (XCS-FEm-DSG3). Th. accuracy and reliability of th. novel XCS-FEm-DSG3 for free vibration analysis of cracked Reissner-mindlin sh.lls are investigated th.ough.solving th.ee numerical examples and comparing with.commercial software ANSYS.

关键词： cracked Reissner-mindlin sh.ll free vibration analysis cell-based smooth.d discrete sh.ar gap meth.d (CS-FEm-DSG3) extended cell-based smooth.d discrete sh.ar gap meth.d (XCS-FEm-DSG3) smooth.d finite element meth.ds (SFEm)

Th. Ph.ton Polarization Parameter of 2h.n, γ）3h.reaction with.Inclusion of th. Electric Quadrupole Contribution

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Ch.nese Ph.sics Letters 2014年第9期31卷 32-35页

作者： h. Sadegh. m. mosavi-Kh.nsari Department of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

We use effective field th.ory （EFT） for th. calculation of neutron-deuteron radiative capture at very low energies. We present h.re th. use of EFT to calculate a low-energy ph.to-nuclear observable in th.ee-body systems, th. ph.ton polarization parameter and and fore-aft asymmetry at th.rmal neutron energies up to next-to-next to leading order （N2 LO）, with.inclasion of th. electric quadrupole contribution. Th. ph.ton polarization parameter in total is found to be Rc = -0.421±0.003 and is in good agreement with.th. oth.r modern th.oretical calculations based on modern nucleon-nucleon potentials. In comparison with.our previous work, a satisfactory agreement with.th. available experimental data is found by inclusion of th. electric quadrupole contribution.

关键词： Polarization

Determination of interface states and th.ir time constant for Au/SnO_2 /n-Si (mOS) capacitors using admittance measurements

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Ch.nese Ph.sics B 2013年第4期22卷 429-433页

作者： h. m. Baran A. Tataroglu Department of Ph.sics Faculty of Arts and Sciences Gazi University

Th. frequency dependence of admittance measurements （capacitance–voltage （C–V ） and conductance–voltage （G/ω–V ）） of Au/SnO2 /n-Si （mOS） capacitors was investigated by taking into account th. effects of th. interface states （N ss ） and series resistance （Rs ） at room temperature. Admittance measurements were carried out in frequency and bias voltage ranges of 1 kh.–1 mh. and （ 5V）–（＋9V）, respectively. Th. values of N ss and R s were determined by using a conductance meth.d and estimating from th. admittance measurements of th. mOS capacitors. At low frequencies, th. interface states can follow th. AC signal and yield excess capacitance and conductance. In addition, th. parallel conductance （G p /ω） versus log（f） curves at various voltages include a peak due to th. presence of interface states. It is observed th.t th. N ss and th.ir time constant （τ） range from 1.23 ×10 12 eV-1 ·cm-2 to 1.47 ×10 12 eV-1 ·cm-2 and from 7.29 ×10-5 s to 1.81 ×10-5s, respectively.

关键词： mOS capacitor admittance measurements interface states

Investigation of microstructure, Natural Frequencies and Vibration modes of Dragonfly Wing

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Journal of Bionic Engineering 2011年第2期8卷 165-173页

作者： h. Rajabi m. mogh.dami A. Darvizeh Faculty of Engineering lslamic Azad University Lahijan Branch Lahijan Iran Department of mech.nical Engineering University of Guilan P.O. Box 3756 Rasht Iran

In th. present work, a th.rough.investigation on th. microstructural and morph.logical aspects of dragonfly wings was carried out using scanning electron microscope. Th.n, based on th.s study and th. previous reports, a precise th.ee-dimensional numerical model was developed and natural frequencies and vibration modes of dragonfly forewing were determined by finite element meth.d. Th. results sh.wn th.t dragonfly wings are made of a series of adaptive materials, wh.ch.form a very complex composite structure. Th.s bio-composite fabrication h.s some unique features and potential benefits. Furth.rmore, th. numerical results sh.w th.t th. first natural frequency of dragonfly wings is about 168 h. and bending is th. predominant deformation mode in th.s stage. Th. accuracy of th. present analysis is verified by comparison of calculated results with.experimental data. Th.s paper may be h.lpful for micro aerial veh.cle design concerning dynamic response.

关键词： insect wing natural frequency vibration mode SEm finite element meth.d