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Cortico-striatal gamma oscillations are modulated by dopamine D3 receptors in dyskinetic rats
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作者 Pengfei Wang Yuewei Bi +6 位作者 Min Li Jiazhi Chen Zhuyong Wang Huantao Wen Ming Zhou Minjie Luo Wangming Zhang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1164-1177,共14页
Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Cu... Long-term levodopa administration can lead to the development of levodopa-induced dyskinesia.Gamma oscillations are a widely recognized hallmark of abnormal neural electrical activity in levodopa-induced dyskinesia.Currently,studies have reported increased oscillation power in cases of levodopa-induced dyskinesia.However,little is known about how the other electrophysiological parameters of gamma oscillations are altered in levodopa-induced dyskinesia.Furthermore,the role of the dopamine D3 receptor,which is implicated in levodopa-induced dyskinesia,in movement disorder-related changes in neural oscillations is unclear.We found that the cortico-striatal functional connectivity of beta oscillations was enhanced in a model of Parkinson’s disease.Furthermore,levodopa application enhanced cortical gamma oscillations in cortico-striatal projections and cortical gamma aperiodic components,as well as bidirectional primary motor cortex(M1)↔dorsolateral striatum gamma flow.Administration of PD128907(a selective dopamine D3 receptor agonist)induced dyskinesia and excessive gamma oscillations with a bidirectional M1↔dorsolateral striatum flow.However,administration of PG01037(a selective dopamine D3 receptor antagonist)attenuated dyskinesia,suppressed gamma oscillations and cortical gamma aperiodic components,and decreased gamma causality in the M1→dorsolateral striatum direction.These findings suggest that the dopamine D3 receptor plays a role in dyskinesia-related oscillatory activity,and that it has potential as a therapeutic target for levodopa-induced dyskinesia. 展开更多
关键词 aperiodic components dopamine D3 receptor dorsolateral striatum functional connectivity gamma oscillations levodopa-induced-dyskinesia local field potentials NEUROMODULATION Parkinson’s disease primary motor cortex
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AlN/β-Ga_(2)O_(3)HEMT频率特性仿真研究
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作者 贺小敏 唐佩正 +3 位作者 刘若琪 宋欣洋 胡继超 苏汉 《人工晶体学报》 CAS 北大核心 2024年第8期1361-1368,共8页
器件的频率特性影响较为复杂,本文利用Sentaurus TCAD研究了AlN势垒层厚度、栅长、栅漏间距和功函数对AlN/β-Ga_(2)O_(3)高电子迁移率晶体管(HEMT)频率特性的影响,得到以下结论:随着AlN势垒层厚度从10 nm增加到25 nm,截止频率(f_(T))... 器件的频率特性影响较为复杂,本文利用Sentaurus TCAD研究了AlN势垒层厚度、栅长、栅漏间距和功函数对AlN/β-Ga_(2)O_(3)高电子迁移率晶体管(HEMT)频率特性的影响,得到以下结论:随着AlN势垒层厚度从10 nm增加到25 nm,截止频率(f_(T))和最高振荡频率(f_(max))分别增加了18和17 GHz,栅电容减小是f_(T)增加的主要原因,同时研究表明势垒层厚度减小有利于增强栅极对沟道电子的控制。栅长从0.9μm减小到0.1μm,f_(T)和f_(max)分别增加了84和98 GHz,其对频率特性的影响远远超过了势垒层厚度;栅长小于0.1μm时,发生短沟道效应。栅漏间距增大时,f_(T)微弱减小,在源电阻和f_(T)共同减小作用下,器件仅在栅源电压(V_(GS))大于-1.2 V时,f_(max)与f_(T)的变化趋势相同。功函数几乎不会影响器件的f_(T)和f_(max),但是功函数的增加改善了器件的夹断特性。本文研究表明,在栅长缩短的同时,增加AlN势垒层厚度、栅漏间距和功函数可以在提高频率特性的同时改善器件的夹断特性,对AlN/β-Ga_(2)O_(3) HEMT器件的设计有一定的指导意义。 展开更多
关键词 β-Ga_(2)O_(3) ALN HEMT 截止频率 最高振荡频率
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A 515-nm laser-pumped idler-resonant femtosecond BiB_(3)O_(6) optical parametric oscillator
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作者 杨金芳 王兆华 +4 位作者 宋贾俊 吕仁冲 王羡之 朱江峰 魏志义 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第1期339-343,共5页
We report on an idler-resonant femtosecond optical parametrical oscillator(OPO)based on BiB_(3)O_(6)(BiBO)crystal,synchronously pumped by a frequency-doubled,mode-locked Yb:KGW laser at 515 nm.The idler wavelengths of... We report on an idler-resonant femtosecond optical parametrical oscillator(OPO)based on BiB_(3)O_(6)(BiBO)crystal,synchronously pumped by a frequency-doubled,mode-locked Yb:KGW laser at 515 nm.The idler wavelengths of OPO can be tuned from 1100 nm to 1540 nm.At a repetition rate of 75.5 MHz,the OPO generates as much as 400 mW of idler power with 3.1 W of pump power,the corresponding pulse duration is 80 fs,which is 1.04 times of Fourier transform-limited(FTL)pulse duration at 1305 nm.In addition,the OPO exhibits excellent beam quality with M^(2)<1.8 at 1150 nm.To the best of our knowledge,this is the first idler-resonant femtosecond OPO pumped by 515 nm. 展开更多
关键词 nonlinear frequency conversion 515-nm laser pumped femtosecond optical parametric oscillator BiB_(3)O_(6)nonlinear crystal
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS KLEIN GORDON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic oscillator
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x^3振荡器周期运动的解析解 被引量:2
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作者 陈海燕 《江汉石油学院学报》 EI CSCD 北大核心 2001年第1期87-88,共2页
给出了 x3振荡器周期运动的解析解 ,并进一步用解析方法证明其振荡周期确与振幅成反比 ,计算出在周期表达式中的无量纲常数 Ec A4=14 , ( Ec A4) =7.4 1 64。
关键词 x^3振荡器 非线性振动 周期运动 解析解
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x^3振荡器的周期的一种计算方法 被引量:13
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作者 陈海燕 《大学物理》 1999年第1期25-26,共2页
用量纲分析的方法获得了x3振荡器的周期。
关键词 X^3振荡器 量纲 周期 非简谐振动
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关于丢番图方程x^3+y^3=pDz^2的通解公式 被引量:2
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作者 王云葵 罗将道 《贵州师范大学学报(自然科学版)》 CAS 2002年第3期87-90,共4页
设p >3是素数 ,D是无平方因子且不被 6k + 1形素数整除的正整数 ,运用初等数论方法 ,获得了丢番图方程x3+y3=pDz2 全部整数解的表达式 ,从而获得了方程在D =1,2 ,3 ,6时全部整数解的通解公式及其解的深刻性质 。
关键词 x^3+y^3+pDz^2 通解公式 广义FERMAT猜想 Tijdemon猜想 丢番图方程 整数解 数论
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x^3振荡器的周期运动 被引量:11
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作者 佘守宪 《大学物理》 2000年第1期19-20,共2页
给出了回复力F 与位移x 的三次方成正比的“x3 振荡器”周期运动的解析解,并证明其振荡周期与振幅成反比.
关键词 x^2振荡器 周期 非线性振动
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CH(X^2Π)与NH_3反应机理的量子化学研究
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作者 张金生 孟庆喜 李明 《西南师范大学学报(自然科学版)》 CAS CSCD 北大核心 2005年第3期515-519,共5页
对CH(X2Π)自由基与NH3的反应进行了量子化学研究.分别在B3LYP/6311++G(d,p),B3LYP/6311++G(3df,3pd),MP2/6311++G(d,p)和MP2/6311++G(3df,3pd)水平优化了反应势能面上各驻点的几何结构,并在QCISD(T)/6311++G(3df,3pd)水平上计算了各驻... 对CH(X2Π)自由基与NH3的反应进行了量子化学研究.分别在B3LYP/6311++G(d,p),B3LYP/6311++G(3df,3pd),MP2/6311++G(d,p)和MP2/6311++G(3df,3pd)水平优化了反应势能面上各驻点的几何结构,并在QCISD(T)/6311++G(3df,3pd)水平上计算了各驻点的能量.通过IRC计算确认了过渡态,确定了反应的机理. 展开更多
关键词 CH(X^П)自由基 氨(NH3) 密度泛函理论(DFT) MP2方法 反应机理
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x^(3)振荡器的周期的近似计算
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作者 谢长珍 《信阳师范学院学报(自然科学版)》 CAS 2001年第1期52-54,共3页
应用牛顿第二定律得到 x3振荡器的运动学方程及其振荡器的周期公式 ;应用数学推导的方法证明 x3振荡器的周期与振幅成反比 ;并借助第一类全椭圆积分在 ρ2→ 1时的近似展开公式及椭圆积分的模数变换得到周期公式中的无量纲常量的近似计... 应用牛顿第二定律得到 x3振荡器的运动学方程及其振荡器的周期公式 ;应用数学推导的方法证明 x3振荡器的周期与振幅成反比 ;并借助第一类全椭圆积分在 ρ2→ 1时的近似展开公式及椭圆积分的模数变换得到周期公式中的无量纲常量的近似计算 ,提供的计算公式的近似程度极高 . 展开更多
关键词 x^(3)振荡器 周期公式 第一类全椭圆积分 椭圆积分模数变换
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关于同余式x^3≡a(modp)的解法
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作者 孙多青 许曰才 《洛阳大学学报》 2000年第4期8-12,共5页
圆满地给出了同余式x3≡a(modp)的解法 ,这里p为大于 3的素数且p a .
关键词 同余式 解法 X^3≡A(MODP) 立方剩余 素数 平方剩余
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含x^3项振子运动研究
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作者 夏清华 《湖北民族学院学报(自然科学版)》 CAS 2005年第2期183-184,共2页
讨论x3振荡器的运动,用四阶龙格-库塔法进行数值求解,在不同的参数情况下,给出了振子运动的相图,直观地显示了振子的规则运动和混沌运动.
关键词 x^3振荡器 数值积分 相图
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简单系统的复杂行为——剖析一个最简单的方程:X^3-1=0
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作者 刘华杰 《科学技术与辩证法》 CSSCI 1989年第4期23-24,共2页
不久前,人们还普遍坚信这种观念:简单系统的行为必是简单的,只要这些系统可用完全清楚的、完全确定的法则刻划出来,那么它们的长期行为将是稳定的和可以预测的。现在,这些看法不得不加以修正,20世纪中叶,物理学家、数学家、生物学家、... 不久前,人们还普遍坚信这种观念:简单系统的行为必是简单的,只要这些系统可用完全清楚的、完全确定的法则刻划出来,那么它们的长期行为将是稳定的和可以预测的。现在,这些看法不得不加以修正,20世纪中叶,物理学家、数学家、生物学家、天文学家共同得到一种新观念:简单系统可能导致复杂行为,复杂系统也可能导致简单行为,更重要的是,复杂性定律普遍适用。 展开更多
关键词 简单系统 复杂行为 X^3-1=0方程
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再谈x^3-3x^2+2x+1在(0,1)上的最大值(高二、高三)
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作者 赵临龙 胡志奇 《数理天地(高中版)》 2002年第1期47-,共1页
此题是第十二届“希望杯”高二年级第二试中的一个大题.本刊收到探讨此题解法的十多篇文章,其中以河南太康一中王国平、许瑞勤二位老师的研究比较全面,故在本刊2001年第7期上登出,此后仍有人继续来稿,本期再发表有新意的两篇.
关键词 x^3-3x^2+2x+1 最大值
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x^3振荡器及其周期
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作者 于凤军 《工科物理》 2000年第4期20-21,共2页
建立了x~3振荡器模型,导出了它的振动周期公式.
关键词 x^3振荡器 振幅 振动周期
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关于x^3+y^3+z^3=D^3的整数解问题初探 被引量:1
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作者 路云才 《鞍山师范学院学报》 2003年第4期5-6,共2页
关于不定方程F(x ,y) =0的整数解问题 ,在多种数论的论著中都有讨论 .本文初步给出了x3+
关键词 x^3+y^3+z^3=D^3 整数解 数论 数学问题 不定方程
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Theoretical Studies on Reaction Mechanisms of HNCS with NH(X^3Σ) 被引量:8
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作者 LIU Peng-jun ZHANG Lian-hua +2 位作者 SUN Hao CHANG Ying-fei WANG Rong-shun 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2006年第5期635-638,共4页
The reaction mechanisms of HNCS with NH(X^3∑ ) were theoretically investigated. The minimum energy paths (MEP) of the reaction were calculated by using the density functional theory(DFT) at the B3LYP/6-311 + ... The reaction mechanisms of HNCS with NH(X^3∑ ) were theoretically investigated. The minimum energy paths (MEP) of the reaction were calculated by using the density functional theory(DFT) at the B3LYP/6-311 + + G^** level. The equilibrium structural parameters, the harmonic vibrational frequencies, the total energies, and the zeropoint energies(ZPE) of all the species were calculated. The single-point energies along the MEP were further refined at the QCISD(T)/6-311 + + G^* * level. It was found that the mechanisms of the HNCS + NH(X^3∑) reaction involve two channels producing the HNC + HNS and the N2H2 + CS products. Channel 1 plays a dominant role and the HNC + HNS are the main preduets. The reaction is exothermie. 展开更多
关键词 HNCS NH(X^3∑) Reaction mechanism Density functional theory(DFT)
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B_2分子A^3∑_u^-—X^3∑_g^-带系振子强度的理论计算
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作者 刘必成 熊烨 《原子与分子物理学报》 CAS CSCD 北大核心 1990年第S1期59-60,共2页
航天运载工具的表面防护层多用含硼的化合物,因此,对硼及硼的化合物在高温情况下的辐射和吸收的研究具有极其重要的意义,截至目前为止,国内外发表的公开资料中尚未有硼分子A^3∑_u^--x^3∑_g^-带系振子强度的实验或理论值的报告,因此,... 航天运载工具的表面防护层多用含硼的化合物,因此,对硼及硼的化合物在高温情况下的辐射和吸收的研究具有极其重要的意义,截至目前为止,国内外发表的公开资料中尚未有硼分子A^3∑_u^--x^3∑_g^-带系振子强度的实验或理论值的报告,因此,从理论上对该量进行计算就很有必要。 展开更多
关键词 振子强度 A^3 B2 X^3 带系 对称空间 分子轨道 防护层 激发组态 对称轨道
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Oscillations during partial oxidation of methane to synthesis gas over Ru/Al_2O_3 catalyst 被引量:3
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作者 Meiliu Wang Weizheng Weng Haozhuan Zheng Xiaodong Yi Chuanjing Huang Huilin Wan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第3期300-305,共6页
Oscillations in temperatures of catalyst bed as well as concentrations of gas phase species at the exit of reactor were observed during the partial oxidation of methane to synthesis gas over Ru/Al2O3 in the temperatur... Oscillations in temperatures of catalyst bed as well as concentrations of gas phase species at the exit of reactor were observed during the partial oxidation of methane to synthesis gas over Ru/Al2O3 in the temperature range of 600 to 850℃. XRD, H2-TPR and in situ Raman techniques was used to characterize the catalyst. Two types of ruthenium species, i.e. the ruthenium species weakly interacted with Al2O3 and that strongly interacted with the support, were identified by H2-TPR experiment. These species are responsible for two types of oscillation profiles observed during the reaction. The oscillations were the result of these ruthenium species switching cyclically between the oxidized state and the reduced state under the reaction condition. These cyclic transformations, in turn, were the result of temperature variations caused by the varying levels of the strongly exothermic CH4 combustion and the highly endothermic CH4 reforming (with H2O and CO2) reactions (or the less exothermic direct partial oxidation of methane to CO and H2), which were favored by the oxidized and the metallic sites, respectively. The major pathway of synthesis gas formation over the catalyst was via the combustion-reforming mechanism. 展开更多
关键词 Ru/Al2O3 methane partial oxidation synthesis gas oscilLATION
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Design of Cylindrical Cam with Oscillating Follower Based on 3D Expansion of Planar Profile Model 被引量:2
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作者 CHEN Junhua LIN Zuan WU Yijie 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期665-670,共6页
Cylindrical cam with oscillating follower is widely applicable and used in many mechanical devices and machines. However, a common error exists in the methods of designing planar profile for oscillating follower cylin... Cylindrical cam with oscillating follower is widely applicable and used in many mechanical devices and machines. However, a common error exists in the methods of designing planar profile for oscillating follower cylinder cam. In this study, we propose a new hypothesis to solve this design problem with the inclusion of deviation angle. On the basis of this new concept, equations for planar profile expansion and methods of calculating pressure angle are deduced by applying 3D expansion formula of the follower's motion orbit. When the pressure angle is less than allowable value, the minimum base radius can be determined by using MATLAB software. Accordingly, the planar profile of oscillating follower cylinder cam is generated by CAD software. This new method is practical and can be easily adopted for the design of oscillating follower cylindrical cam with desirable accuracy. We applied the method in the design of cylindrical cam for paper feeding mechanism used in high-speed printers. We calculated the planar profile and used it to direct the NC machine for the manufacture of the groove of cylindrical cam. The improved cylindrical cam met all of the requirements of speed and accuracy demanded by high-speed printers. Therefore, our new method has been validated by practical application. 展开更多
关键词 oscillating follower cylindrical cam 3D expansion pressure angle radius of base circle PROFILE
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