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Differential protein expression in substantia nigra induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine in a mouse model of chronic Parkinson’s disease

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Neural Regeneration Research 2008年第5期3卷 482-485页

作者： Wenbin tu Furong Xu Guoguang peng Department of Neurology First Hospital of Chongqing Medical University Chongqing 400016 China

BACKGROUND： To date, a complete protein expression profile of the midbrain substantia nigra in a mouse model of chronic Parkinson＇s disease, induced by 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine （MPTP）, does not exist. In addition, there are no reports of analysis of differential protein expression. OBJECTIVE： To separate and evaluate MPTP-induced differential protein expression through the use of proteomics in the substantia nigra of a mouse model of chronic Parkinson＇s disease. DESIGN： Randomized controlled animal study. SETTING： Department of Neurology, the First Affiliated Hospital, Chongqing Medical University. MATERIALS： Sixteen 8-10-week old, healthy, male, C57BL mice, weighing 20-25 g, and of clean grade, were provided by the Experimental Animal Center of Chongqing Medical University. The experimental animals were disposed according to ethical criteria. MPTP was provided by Sigma Company, USA; Pdquest 2D image analysis software and gelatum/irradiance image analysis system （ChemiDoc XRS） by Bio-Rad, USA; and Voyager DE-PROMALD1-TOF-MS mass spectroscopy analyzer by AB1 Company, USA. METHODS： This study was performed in Chongqing Neurological Laboratory between November 2006 and July 2007. Mice were randomly divided into model and control groups, with 8 mice in each group. Mice in the model group were received a subcutaneous injection of MPTP （25 mg＆g）, twice a week, for five successive weeks, to establish a chronic Parkinson＇s disease model. Mice in the control group received the same volume of a subcutaneous saline injection at the same time points. Mice were sacrificed by anesthesia to rapidly obtain the midbrain for protein separation of the substantia nigra. MAIN OUTCOME MEASURES：（1） 2-ED handbook （Bio-Rad Company） was referenced for two-dimensional electrophoresis, （2） PDQUEST8,0 analytical electrophoresis pattern was adopted to evaluate differential protein expression. （3） Peptide mass finger print map and data were retrieved on http：//***

关键词： Parkinson's disease 1-methyl-4-phenyl-l, 2, 3, 6-tetrahydropyridine mice substantia nigra proteomics

Transcript Regulation of Human Telomerase Reverse Transcriptase by c-myc and mad1

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Acta Biochimica et Biophysica Sinica 2005年第1期37卷 32-38页

作者： Lin ZOU~# peng-Hui ZHANG Chun-Li LUO zhi-Guang tu~* Faculty of Laboratory Medicine,Chongqing University of Medical Sciences.Chongqing 400016,China Faculty of Laboratory Medicine Chongqing University of Medical SciencesChongqing 400016 China

Telomerase activity is highly positive correlated to most malignant *** telomerasereverse transcriptase(hTERT)is the rate-limiting factor of telomerase *** studies have shownthat the expression of hTERT is mainly determined by its transcript *** the transcript regula-tion factors of hTERT,c-myc and mad 1 are well ***,we constructed c-myc and madl eukaryoticexpression vectors,then co-transfected them with the wild-type(Tw)or mutant hTERT promoter(Td)luciferase reporter plasmid,which were double-mutated in the E-box sequences from CACGTG to CACCTGof *** change of luciferase activity in different cells was *** results showed that Tw wasobviously activated in T24 and EJ bladder cancer cells,but not in normal fibrocytes,c-myc and madl hadpositive and negative effects respectively on the Tw transcript in a dose-dependent manner,while the roles ofc-myc and madl in regulating the Td transcript were reversed,c-myc combined with madl can down-regulate Tw but not *** observations indicate that c-myc and madl can regulate the hTERT transcriptin a different manner in hTERT positive cells,but not in normal *** may provide an insight into sometelornerase-related carcinogenesis mechanisms.

关键词： c-myc: mad1 hTERT promoter transcript regulation

NUMERICAL SIMULATION OF PROPAGATION AND BREAKING PROCESSES OF A FOCUSED WAVES GROUP

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Journal of Hydrodynamics 2012年第3期24卷 399-409页

作者： HUANG Zong-liu LIN peng-zhi State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065China

A two-dimensional numerical wave flume is developed to study the focused waves group propagation and the consequent breaking processes. The numerical model is based on the Reynolds-Averaged Navier-Stokes （PANS） equations, with the standard k - c turbulence model to simulate the turbulence effects. To track the complicated and broken free-surface, the Volume Of Fluid （VOF） method is employed. The numerical model combines the ＂Partial Cell Treatment （PCT）＂ method with the ＂Locally Relative Stationary （LRS）＂ concept to treat the moving wave paddle so that various waves can be generated directly in a fixed Cartesian grid system. The theoretical results of the linear and nonlinear waves are used to validate the numerical wave flume firstly, and then a plunging breaking wave created by a focused waves group is simulated. The numerical results are compared to the experimental data and other simulation results, with very good agreements. The turbulence intensity, the flow field and the energy dissipation in the breaking processes are analyzed based on the numerical results. It is shown that the present numerical model is efficient and accurate for studying the waves group generation, the waves packet propagation, and the wave breaking processes.

关键词： focused waves group plunging breaking Volume Of Fluid (VOF) k - ε turbulence model irregular wave maker

Numerical Simulation of the Vortex-Induced Vibration of A Curved Flexible Riser in Shear Flow

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China Ocean Engineering 2018年第3期32卷 301-311页

作者： ZHU Hong-jun LIN peng-zhi State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University

A series of fully three-dimensional(3 D) numerical simulations of flow past a free-to-oscillate curved flexible riser in shear flow were conducted at Reynolds number of 185–1015. The numerical results obtained by the two-way fluid–structure interaction(FSI) simulations are in good agreement with the experimental results reported in the earlier study. It is further found that the frequency transition is out of phase not only in the inline(IL) and crossflow(CF) directions but also along the span direction. The mode competition leads to the non-zero nodes of the rootmean-square(RMS) amplitude and the relatively chaotic trajectories. The fluid–structure interaction is to some extent reflected by the transverse velocity of the ambient fluid, which reaches the maximum value when the riser reaches the equilibrium position. Moreover, the local maximum transverse velocities occur at the peak CF amplitudes, and the values are relatively large when the vibration is in the resonance regions. The 3 D vortex columns are shed nearly parallel to the axis of the curved flexible riser. As the local Reynolds number increases from 0 at the bottom of the riser to the maximum value at the top, the wake undergoes a transition from a two-dimensional structure to a 3 D one. More irregular small-scale vortices appeared at the wake region of the riser, undergoing large amplitude responses.

关键词： vortex-induced vibration flexible riser shear flow fluid–structure interaction computational fluid dynamics

Depth-resolved numerical model of dam break mud flows with Herschel-Bulkley rheology

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Journal of Mountain Science 2022年第4期19卷 1001-1017页

作者： TANG Jin-bo LIN peng-zhi CUI peng State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of SciencesInstitute of Mountain Hazards and EnvironmentChinese Academy of Sciences and Ministry of Water ConservancyChengdu 610041China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

Mud flows are common phenomena in mountainous areas,which can threaten human safety and cause property losses under certain extreme *** the dynamic characteristics of mud flows,especially in the vertical direction,is helpful for risk reduction and hazard *** this study,a 2D depth-resolved numerical model based on Herschel-Bulkley rheology was developed to study the vertical structures of unsteady mud flows with a *** numerical model was solved by the projection method,and the free surface of mud flows was captured through the VOF *** fully validate this new model,a series of laboratory experiments involving dam break mud flows were conducted,and the mud flow heights,bottom pressures and envelopes of mud residuum were *** numerical model proposed in this study was first validated by the steady-state solution for uniform flows of Herschel-Bulkley fluid on an inclined ***,the simulated and measured mud flow heights,bottom pressures at different x locations and envelopes with different bed slopes showed good ***,the numerical results for a Herschel-Bulkley fluid dam break flow were used to validate the proposed model,which further revealed good *** that,the scenarios in which mud flows impact on a structure were numerically studied,and the vertical profiles of the front velocity and impact pressure on the structure were analyzed and *** results show that a plug layer was formed in the mud flow under unsteady and nonuniform flow conditions,and the impact pressure on the structure was dominated by the dynamic *** addition,the vertical position with the maximum impact pressure acting on the structure was not at the bottom or the surface of the mud flows,and the normalized vertical position rose as the yield stress and consistency coefficient increase for Herschel-Bulkley fluids.

关键词： Mud flows Herschel-Bulkley rheology Depth-resolved model Numerical simulation Vertical profiles

Effects of time-varying liquid bridge forces on rheological properties,and resulting extrudability and constructability of three-dimensional printing mortar

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Frontiers of Structural and Civil Engineering 2023年第9期17卷 1295-1309页

作者： peng zhi Yu-Ching WU Timon RABCZUK Department of Structural Engineering Tongji UniversityShanghai 200092China Institute of Structural Mechanics Bauhaus University of WeimarWeimar 99423Germany

Extrudability and constructability are two important,yet contradictory issues pertaining to the construction of three-dimensional(3D)printing *** is easily achieved when 3D printing cement mortar has a high water content and low cohesion,but the printed structure is easily ***,a 3D printing cement mortar with a low water content and high cohesion has a relatively stable printed structure although the cement mortar might not be *** study proposes a particle-based method to simulate 3D printing mortar extrusion and construction as an overall planning tool for building ***,a discrete element model with time-varying liquid bridge forces is developed to investigate the microscopic effects of these forces on global rheological ***,a series of numerical simulations relevant to 3D printable mortar extrudability and constructability are carried *** study demonstrates that the effects of time-varying liquid bridge forces on rheological properties and the resulting extrudability and constructability of 3D printing mortar are ***,an optimized region that satisfies both the extrusion and construction requirements is provided for 3D printing industry as a reference.

关键词： particle-based simulation liquid bridge force rheological property 3D printing mortar extrudability constructability

QSAR of Estrogen of Bisphenol A with 3D Vector of Atomic Property Correlation

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Chinese Journal of Structural Chemistry 2007年第8期26卷 988-994页

作者： CHEN zhi-Tao ZHOU peng HE Liu LI zhi-Liang College of Chemistry and Chemical Engineering Chongqing University Chongqing 400044 China College of Biomedical Engineering Chongqing University Chongqing 400044 China

Considering atomic property vector and atomic correlative function, the 3-dimensional structural vector of atomic property correlation （3D-VAPC）, a novel descriptor,is defined to characterize a 3-dimensional molecular structure by introducing self-adaptability regulation mechanism and the idea of orientating to customers. Characterizing the structures of 25 bisphenol A compounds by this vector, the QSAR models of three kinds of estrogen activities （ER affinities, gene induction and cell proliferation） have high multiple correlation coefficient （Rcum^2=0.933, 0.813, 0.959） and cross verification coefficient （Qcum^2=0.847, 0.953, 0.798） by support vector machine （SVM）, which suits for nonlinear circumstances. The above results show that the models successfully express the correlation between structure and three kinds of estrogen activities. Therefore, 3D-VAPC exactly reflects the molecular structural information and SVM method correctly describes the correlation between information and property of the compounds.

关键词： 3D vector of atomic property correlation (3D-VAPC) support vector machine (SVM) quantitative structure-activity relationship (QSAR) bisphenol A estrogen

Distributed Periodic Event-Triggered Optimal Control of DC Microgrids Based on Virtual Incremental Cost

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 624-634页

作者： Jiangkai peng Bo Fan Zhenghong tu Wei Zhang Wenxin Liu IEEE the Smart Microgrids and Renewable Technology(SMRT)Research Laboratory Department of Electrical and Computer EngineeringLehigh University the Department of Energy(AAU Energy) Aalborg University

This article presents a distributed periodic eventtriggered(PET)optimal control scheme to achieve generation cost minimization and average bus voltage regulation in DC *** order to accommodate the generation constraints of the distributed generators(DGs),a virtual incremental cost is firstly designed,based on which an optimality condition is derived to facilitate the control *** meet the discrete-time(DT)nature of modern control systems,the optimal controller is directly developed in the DT ***,to reduce the communication requirement among the controllers,a distributed event-triggered mechanism is introduced for the DT optimal *** event-triggered condition is detected periodically and therefore naturally avoids the Zeno *** closed-loop system stability is proved by the Lyapunov synthesis for switched *** generation cost minimization and average bus voltage regulation are obtained at the equilibrium ***,switch-level microgrid simulations validate the performance of the proposed optimal controller.

关键词： Bus voltage regulation DC microgrids event-triggered control distributed optimal control generation cost minimization

骨科机器人辅助微创精准手术治疗胸腰段骨折的初步经验

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脊柱外科杂志 2020年第6期18卷 369-375页

作者：于笑笙陈修远陈皓劳立峰王淑容涂志朋韩应超陈智张煜辉沈洪兴上海交通大学医学院附属仁济医院脊柱外科上海200127

目的比较骨科机器人辅助经皮椎弓根螺钉内固定术治疗胸腰段骨折与传统后路椎弓根螺钉内固定术、C形臂X线机透视导航经皮椎弓根螺钉内固定术的临床疗效,探讨机器人辅助手术治疗胸腰段骨折的微创化与精准化价值。方法2018年2月—2019年6月... 详细信息

目的比较骨科机器人辅助经皮椎弓根螺钉内固定术治疗胸腰段骨折与传统后路椎弓根螺钉内固定术、C形臂X线机透视导航经皮椎弓根螺钉内固定术的临床疗效,探讨机器人辅助手术治疗胸腰段骨折的微创化与精准化价值。方法2018年2月—2019年6月,收治无神经症状胸腰段骨折患者52例,18例接受机器人辅助经皮椎弓根螺钉内固定术治疗(机器人组),15例接受C形臂X线机透视导航经皮椎弓根螺钉内固定术治疗(透视组),19例接受传统后路椎弓根螺钉内固定术治疗(传统组)。记录并比较3组的手术时间、透视时间、辐射剂量、术中出血量、置钉准确率、卧床时间、住院天数,术前、术后6个月伤椎前缘相对高度及Cobb角,以及术前、术后3 d、术后6个月的疼痛视觉模拟量表(VAS)评分和日本骨科学会(JOA)评分。结果所有手术顺利完成,未出现手术相关并发症。所有患者随访6~12个月,平均8个月。机器人组和透视组的手术时间、术中出血量、卧床时间、住院天数均少于传统组,差异有统计学意义(P0.05);机器人组与透视组术后3 d VAS评分优于传统组且差异有统计学意义(P0.05)。结论机器人辅助经皮内固定术是治疗无神经症状胸腰段骨折的有效方法,具有手术时间短、精度高、创伤小、辐射少、患者术后恢复快等优势,满足适应证时可作为优先选择。

关键词：胸椎腰椎脊柱骨折内固定器外科手术,微创机器人