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在抑郁症大鼠模型中MiRNA-103-3p调控Rab10促进神经细胞自噬

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南方医科大学学报 2024年第7期44卷 1315-1326页

作者：张叶明张袁祥沈学彬王国栋朱磊皖南医学院药学院安徽芜湖241002 安徽省多糖药物工程技术研究中心安徽芜湖241002 安徽省皖南地区植物药活性物质筛选与再评价工程实验室安徽芜湖241002 安徽省代谢性疾病药物基础研究创新中心安徽芜湖241002

目的探讨与神经保护相关的基因Rab10在抑郁症体内外模型中发挥的功能和作用机制。方法选取36只大鼠作为慢性应激模型组(CUMS组),每只大鼠单笼饲养,进行6周慢性不可预测温和应激,另选取12只作为对照组。CUMS组大鼠完成6周CUMS刺激后,根... 详细信息

目的探讨与神经保护相关的基因Rab10在抑郁症体内外模型中发挥的功能和作用机制。方法选取36只大鼠作为慢性应激模型组(CUMS组),每只大鼠单笼饲养,进行6周慢性不可预测温和应激,另选取12只作为对照组。CUMS组大鼠完成6周CUMS刺激后,根据旷场实验数据和体质量分成3组(12只/组):CUMS+生理盐水组、CUMS+AAV载体组和CUMS+AAV过表达Rab10组,CUMS+saline组大鼠侧脑室注射生理盐水;CUMS+AAV组大鼠侧脑室注射AAV空病毒载体;CUMS+AAV-oe-Rab10组大鼠侧脑室注射AAV过表达Rab10载体实现Rab10基因过表达,CUMS刺激在整个实验期间持续进行。对照组大鼠始终不进行任何刺激。利用大鼠行为学指标的变化评价大鼠抑郁状态。构建CORT诱导的PC12细胞模型,CCK-8法检测细胞活力。通过TargetScan数据库预测与Rab10相互作用的miRNA及miRNA结合位点,并结合双荧光素酶和RIP实验探究miRNA-103-3p与Rab10的相互作用。在CORT刺激的PC12细胞中过表达Rab10,或在转染miRNA-103-3p inhibitor基础上沉默Rab10,qRT-PCR法检测miRNA-103-3p和Rab10的表达水平;Western blotting检测细胞中Rab10、BDNF、CREB、p62、Beclin-1、Wnt3a、Gsk3β、磷酸化(p)-Gsk3β和β-catenin的蛋白含量。结果病毒过表达Rab10后明显改善CUMS大鼠行为学指标(P<0.05)。qRT-PCR和Western blotting证实Rab10基因在CUMS大鼠海马与CORT诱导的PC12细胞中表达下调(P<0.05)。生物信息学结合双荧光素酶和RIP实验证实miRNA-103-3p靶向Rab10(P<0.05)。过表达Rab10或沉默miRNA-103-3p激活了Wnt/β-catenin信号通路,上调BDNF、CREB和Beclin-1的含量,下调p62蛋白的表达(P<0.05);下调miRNA-103-3p的基础上沉默Rab10逆转了miRNA-103-3p的作用(P<0.05)。结论miRNA103-3p靶向Rab10激活Wnt/β-catenin信号通路,改善神经细胞的可塑性,促进细胞自噬,从而对抗CORT诱导的PC12细胞损伤。

关键词： Rab10 miRNA-103-3p 神经可塑性自噬抑郁症

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贴片式复合模态型直线超声电机的仿真与试验评价

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振动与冲击 2024年第14期43卷 253-258,307页

作者：云浩魏绍亮原路生张业明河南理工大学机械与动力工程学院河南焦作454000 南京航天航空大学航空航天结构力学及控制全国重点实验室南京210016

为了实现结构紧凑、低电压驱动、大推力输出以及高精密定位等性能目标,该研究提出了一种贴片式复合模态型直线超声电机。该电机的定子结构采用贴片式压电陶瓷作为激励单元,通过同时激发定子的B 12和B 2两种弯曲振动模态,实现了两个驱动... 详细信息

为了实现结构紧凑、低电压驱动、大推力输出以及高精密定位等性能目标,该研究提出了一种贴片式复合模态型直线超声电机。该电机的定子结构采用贴片式压电陶瓷作为激励单元,通过同时激发定子的B 12和B 2两种弯曲振动模态,实现了两个驱动足处的交替椭圆轨迹运动,借此利用摩擦力驱动动子进行直线运动。首先,应用有限元仿真软件COMSOL对定子的模态和频率响应进行了仿真分析。仿真结果表明,定子上两驱动足处能够实现预期的椭圆运动轨迹。随后,加工了电机的定子并进行了导纳测试,验证了有限元仿真的正确性。最后,制作了超声电机的原理样机,并通过一系列试验评估了其输出性能。试验结果表明:在100 Vpp电压和66.58 kHz频率条件下,电机的最大空载速度和最大推力分别达到了82.9 mm/s和0.52 N;在1.2 N的预压力作用下,电机的启动电压死区为12 Vpp;在周期为20的正弦波电压信号下,电机实现了2.1μm的步进位移。该研究为贴片式复合模态型直线超声电机的设计和应用提供了重要的理论与试验依据。

关键词：超声电机压电陶瓷有限元仿真死区

Overall Life Cycle Comprehensive Assessment of Pneumatic and Electric Actuator

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 584-594页

作者： zhang yeming CAI Maolin School of Mechanical and Power Engineering Henan Polytechnic University School of Automation Science and Electrical Engineering BeihangUniversity

Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries. The two kinds of actuators can replace each other in most fields, such as the point to point transmission occasion and some rotating occasions. However, there are very few research results about the advantages and disadvantages of two kinds of actuators under the same working conditions so far. In this paper, a novel comprehensive assessment method, named as overall life cycle comprehensive assessment （OLCCA）, is proposed for comparison and assessment of pneumatic and electric actuators. OLCCA contains mechanical properties evaluation （MPE）, life cycle cost analysis based on users （LCCABOU） and life cycle environmental impact analysis （LCEIA） algorithm in order to solve three difficult problems： mechanical properties assessment, cost analysis and environmental impact assessment about actuators. The mechanical properties evaluation of actuators is a multi-objective optimization problem. The fuzzy data quantification and information entropy methods are combined to establish MPE algorithm of actuators. Two kinds of pneumatic actuators and electric actuators with similar bearing capacity and similar work stroke were taken for example to verify the correctness of MPE algorithm. The case study of MPE algorithm for actuators verified its correctness. LCCABOU for actuators is also set up. Considering cost complex structure of pneumatic actuators, public device cost even method （PDCEM） is firstly presented to solve cost division of public devices such as compressors, aftercooler, receivers, etc. LCCABOU method is also effective and verified by the three groups of pneumatic actuators and electric actuators. Finally, LCEIA model of actuators is established for the environmental impact assessment of actuators. LCEIA data collection method and model establishment procedure for actuators are also put forward. With Simapro 7, LCEIA comparison results of six actuators can be obtaine

关键词： actuator mechanical properties evaluation life cycle cost public device cost even method life cycle assessment

Analysis of Power Matching on Energy Savings of a Pneumatic Rotary Actuator Servo-Control System

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Chinese Journal of Mechanical Engineering 2020年第2期33卷 87-99页

作者： yeming zhang Hongwei Yue Ke Li Maolin Cai School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China School of Mechanical and Electrical Engineering Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

When saving energy in a pneumatic system,the problem of energy losses is usually solved by reducing the air supply *** power-matching method is applied to optimize the air-supply pressure of the pneumatic system,and the energy-saving effect is verified by ***,the experimental platform of a pneumatic rotary actuator servo-control system is built,and the mechanism of the valve-controlled cylinder system is ***,the output power characteristics and load characteristics of the system are derived,and their characteristic curves are *** employed air compressor is considered as a constant-pressure source of a quantitative pump,and the power characteristic of the system is *** power source characteristic curve should envelope the output characteristic curve and load characteristic *** minimum gas supply pressure obtained by power matching represents the optimal gas supply *** comparative experiments under two different gas supply pressure conditions show that the system under the optimal gas supply pressure can greatly reduce energy losses.

关键词： Pneumatic rotary actuator Energy savings Gas supply pressure Characteristic curve Power matching

Medical Grabbing Servo System with Friction Compensation Based on the Differential Evolution Algorithm

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Chinese Journal of Mechanical Engineering 2021年第6期34卷 316-330页

作者： yeming zhang Kaimin Li Meng Xu Junlei Liu Hongwei Yue School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo454000China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310027China Orthopedics Department of People’s Liberation Army General Hospital Beijing100853China

This paper introduces a pneumatic finger cylinder servo control system for medical ***,according to the physical structure of the proportional directional valve and the pneumatic cylinder,the state equation of the gas in the servo system was *** Stribeck friction compensation model of a pneumatic finger cylinder controlled by a proportional valve was established and the experimental platform *** allow the system output to bet-ter track the change in the input signal,the flow-gain compensation method was *** this basis,a friction compensation control strategy based on a differential evolution algorithm was proposed and applied to the position control system of a pneumatic finger ***,the strategy was compared with the traditional proportional derivative(PD)strategy and that with friction *** experimental results showed that the position accuracy of the finger cylinder position control system can be improved by using the friction compensation strategy based on the differential evolution algorithm to optimize the PD parameters.

关键词： Position control Friction compensation Differential evolution Parameter optimization

Study on roasting process of zircon-silica sol ceramic mould

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China Foundry 2011年第2期8卷 187-189页

作者： zhang yeming Zeng Ming Hu Li Liu Xingang zhang Congzheng School of Materials Science and Engineering Xihua University Chengdu 610039 China

Dry stock of silica sol ceramic mould was prepared by using of colloidal moulding technique with an optimized vacuum drying process. Effect of roasting process on the shrinkage rate and compressive strength of zircon-silica sol ceramic mould, and the relationship between the roasting temperature and microstructure of zirconsilica sol ceramic mould were studied. The optimum roasting temperature of zircon-silica sol ceramic mould gained by the experiments is 900~C and the holding time is 2 h. The scanning electron microscope （SEM） observation showed the growth of refractory particles during the roasting process. The occurrence of sintering was observed in the zircon-silica sol ceramic mould when roasting temperature was above 1,000℃.

关键词： zircon-silica sol ceramic mould roasting process shrinkage rate compressive strength SEM

Interfacial microstructure and properties of diamond/Cu-xCr composites for electronic packaging applications

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Rare Metals 2011年第1期30卷 94-98页

作者： zhang Ximin GUO Hong YIN Fazhang FAN yeming zhang Yongzhong National Engineering Research Center for Nonferrous Metals Composites General Research Institute for Non-ferrous MetalsBeijing 100088China

Diamond/Cu-xCr composites were fabricated by pressure infiltration *** thermal conductivities of diamond/Cu-xCr（x = 0.1,0.5,0.8） composites were above 650 W/mK,higher than that of diamond/Cu *** tensile strengths ranged from 186 to 225 MPa,and the bonding strengths ranged from 400 to 525 *** of Cr element on the thermo-physical properties and interface structures were *** intermediate layer was confirmed as Cr3C2 and the amount of Cr3C2 increased with the increase of Cr concentration in Cu-xCr *** the Cr concentration was up to 0.5 wt.%,the content of the Cr3C2 layer was *** the thickness of the Cr3C2 layer became larger,the composites showed a lower thermal conductivity but higher mechanical *** coefficients of thermal expansion（CTE） of diamond/Cu-xCr（x = 0.1,0.5,0.8） composites were in good agreement with the predictions of the Kerner＇ model.

关键词： composite materials copper interfaces bonding electronic packaging infiltration

Nonlinear Control of Magnetically Coupled Rodless Cylinder Position Servo System

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Chinese Journal of Mechanical Engineering 2023年第6期36卷 212-229页

作者： yeming zhang Demin Kong Gonghua Jin Yan Shi Maolin Cai Shuping Li Baozhan Lv School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo 454000China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Magnetically coupled rodless cylinders are widely used in the coordinate positioning of mechanical arms,electro-static paintings,and other industrial ***,they exhibit strong nonlinear characteristics,which lead to low servo control *** this study,a mass-flow equation through the valve port was derived to improve the control performance,considering the characteristics of the dynamics and throttle-hole ***,a fric-tion model combining static,viscous,and Coulomb friction with a zero-velocity interval was *** addition,energy and dynamic models were set for the experimental investigation of the magnetically coupled rodless cylin-der.A nonlinear mathematical model for the position of the magnetically coupled rodless cylinder was *** incremental PID controller was designed for the magnetically coupled rodless cylinder to control this system,and the PID parameters were adjusted online using RBF neural *** response results of the PID parameters based on the RBF neural network were compared with those of the traditional incremental PID control,which proved the superiority of the optimization control algorithm of the incremental PID parameters based on the RBF neural network servo control *** experimental results of this model were compared with the simulation *** average error between the established model and the actual system was 0.005175054(m),which was approximately 2.588%of the total travel length,demonstrating the accuracy of the theoretical model.

关键词： Magnetically coupled rodless cylinder Nonlinear model Position control Radial basis function neural network(RBF-NN) Neural network(NN)

Sm-Nd,Pb-Pb and Rb-Sr Isotopic Dating and Its Dynamic Implications for the Proterozoic Augen Granite in the Yunkai Area,Western Guangdong Province

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 289-296页

作者： PENG Songbai zhang yeming ZHAN Mingguo CHEN Fuwen QIU Ruizhao Yichang Institute of Geology and Mineral Resources CAGSYichang 443003Hubei

The samples of ductile-rheologic deformational augen granite from the Yunkai uplift area, western Guangdong province, were determined by the whole-rock Sm-Nd, Pb-Pb and Rb-Sr isotopic dating to have an Sm-Nd isochron age of 1414±68 Ma, a Pb-Pb isochron age of 1388±90 Ma and a Rb-Sr isochron age of 490±36 Ma. The first two ages are interpreted as the formation age of this suite of granite and the last age represents the timing of the tectono-thermal event of Caledonian ductile-rheologic shear partial melting. It is indicated that in the study area not only an orogeny took place in the Caledonian, but also a more important tectono-magmatic activity occurred in the Meso-proterozoic there, which may be related to the subduction-collision between the Yangtze block and Cathaysia block.

关键词： Yunkai area Proterozoic augen granite isotopic dating ductile-rheologic shear