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Changes of p38 Mitogen-activated Protein Kinase and Apoptosis after Spinal Cord Injury

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Chinese Medical Sciences Journal 2005年第4期20卷 241-241页

作者： Xin-yu Zhang Chu-song Zhou zheng-da kuang Department of Orthopaedics General Hospital of Chinese People＇s Armed Police Forces Beijing 100039 Department of Orthopaedics Zhujiang Hospital the First Military Medical University Guangzhou 510282

There were very few studies about signal transduction of apoptosis of the spinal cord injury （SCI）. We applied spinal cord compression rats model （Nystrom＇s method） to study the changes of p38 mitogen-activated p... 详细信息

关键词： p38 有丝分裂蛋白激酶脊椎损伤细胞凋亡

Fracture Analysis of Cast Iron Materials with Cracks Based on Elastoplastic Extended Finite Element Method

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Acta Mechanica Solida Sinica 2019年第2期32卷 201-214页

作者： Yanjun Chang Qiao Song zheng kuang Keshi Zhang Zhanguang zheng College of Civil Engineering and Architecture Guangxi University Nanning 530004 China College of Mechanical Engineering Guangxi University Nanning 530004 China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi University Nanning 530004 China Key Laboratory of Engineering Disaster Prevention and Structural Safety of Ministry of Education Guangxi University Nanning 530004 China

Based on the ABAQUS platform for finite element analysis, the extended finite element method (XFEM) considering elastoplastic constitutive relationship is developed, by which the displacement discontinuity across the crack surface and the strong nonlinearity near the crack tip can be described more accurately. The strip specimens with unilateral cracks and central cracks under uniaxial tension are simulated using the XFEM and the FEM, respectively. The J-integral across the crack on each incremen t is calcula ted using the equivale nt domain integral met hod (EDIM), the interaction integral met hod and the FEM, respectively. The effec ts of mesh size and mesh shape near the crack tip, element type and different calculation methods on the accuracy of J-integral are analyzed. The simulation results show that the XFEM is more accurate than the FEM with the same element size and type. The fracture tests of cast iron specimens with unilateral cracks under uniaxial tension are performed, and the J-integral criterion is valid to predict the fracture initiation in numerical simulation. The critical value of J-integral is calculated using the EDIM of the XFEM. The comparisons demonstrate that the simulated elastoplastic load-displacement curves with the XFEM are in good agreement with the experimental results.

关键词： J-Integral Extended finite element Elastoplasticity Fracture criterion

Downstream Channel Evolution and Its Causes in the Yuan River during the Qing Dynasty

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Journal of Earth Science 2023年第4期34卷 1263-1271页

作者： dandan zheng Yuhui Gui Jian kuang He Bing School of Arts and Communication China University of GeosciencesWuhan 430074China School of Geography and Information Engineering China University of GeosciencesWuhan 430078China School of Urban Design Wuhan UniversityWuhan 430072China

The determination of channel evolutions and the causes is important for reconstructing the evolutionary history of river *** study aimed to elucidate the downstream channel evolution of the Yuan River in Hunan Province,China,during the Qing Dynasty via Landsat 8 satellite image data and relevant *** objective was to establish the modes of channel evolution and discuss the significance of historical climate *** downstream paleochannel of the Yuan River was identified in the Late Ming Dynasty and Early Qing Dynasty(1600–1644 AD),the Kangxi-Qianlong periods of the Qing Dynasty(1661–1796 AD),the Late Qing Dynasty(1840–1912 AD),and the World War II(1939–1945 AD),and three main modes of river evolution were *** remote sensing data and the ancient literature,the evolution characteristics of the paleochannel in the Lower Yuan River were analyzed and its distribution across historical periods was comprehensively *** findings reveal a strong correlation between channel evolution,flood events,and climate *** flood events that occurred from the Late Qing Dynasty to the World War II caused a high rate of channel evolution,demonstrating the combined effects of climate change and human *** findings will help adopt robust and resilient hydrological management methods in the future of a changing climate.

关键词： Qing Dynasty downstream of Yuan River river evolution river evolution causes cli-mate change climate change channel evolution.

Measuring Network Configuration of the Yangtze River Middle Reaches Urban Agglomeration:Based on Modified Radiation Model

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Chinese Geographical Science 2020年第4期30卷 677-694页

作者： zheng Wensheng kuang Aiping WANG Xiaofang CHEN Jing Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province Central China Normal UniversityWuhan 430079China Academy of Wuhan Metropolitan Area Hubei Development and Reform Commission&Central China Normal UniversityWuhan 430079China Hubei Institute of Economic and Social Development Central China Normal UniversityWuhan 430079China Wuhan Branch of China Tourism Academy Central China Normal UniversityWuhan 430079China

The objective of this study is to develop a framework for re-examining and re-defining the classical concepts of spatial interaction and reorganization in the urban *** introduce a modified radiation model for spatial interactions,coupled with migration big data,transport accessibility algorithm,and city competitiveness assessment for efficient distribution of the inter-city flow through the *** Yangtze River Middle Reaches(YRMR)urban agglomeration(UA)is chosen as the case study region to systematically identify and measure its spatial configuration and to gain insights for other UAs‘sustainable development in *** results are also compared with those computed by the classical gravity model to systematically discuss the applicability of spatial interaction laws and models,and related practical policies for regional sustainable development are discussed based on the findings as *** conclusions are highlighted below:1)Combining with the?city network paradigm‘and?central place theory‘can better express the spatial configurations of city systems in the context of?space of flows‘;2)The results validate the potentialities of a multi-analysis framework to assess the spatial configurations of city network based on the improved radiation model and network analysis tools;3)The applications of spatial interaction models should be considered according to the specific geographical entity and its spatial scale.

关键词： spatial interaction city network radiation model gravity model urban agglomeration

A fractal and scale-free model of complex networks with hub attraction behaviors

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Science China(Information Sciences) 2015年第1期58卷 178-187页

作者： kuang Li zheng BoJin LI DeYi LI YuanXiang SUN Yu State Key Laboratory of Software Engineering Computer SchoolWuhan University College of Computer Science South-Central University For Nationalities School of Software Tsinghua University School of Computer and Electronics and Information Guangxi University

It is widely believed that fractality of complex networks originate from hub repulsion behaviors(anticorrelation or disassortativity), which means that large degree nodes tend to connect with small degree *** hypothesis was demonstrated by a dynamical growth model, which evolves as the inverse renormalization procedure, proposed by Song et al. Now we find that the dynamical growth model is based on the assumption that all the cross-box links have the same probability e to link to the most connected nodes inside each ***, we modify the growth model by adopting the flexible probability e, which makes hubs to have higher probability to connect with hubs than non-hubs. With this model, we find that some fractal and scale-free networks have hub attraction behaviors(correlation or assortativity). The results are the counter-examples of former beliefs. Actually, the real-world collaboration network of movie actors also is fractal and shows assortative mixing.

关键词： scale-free fractal network self-similarity fractal dimension hub attraction

GLOBAL STABILITY OF ENDEMIC EQUILIBRIUM POINT OF BASIC VIRUS INFECTION MODEL WITH APPLICATION TO HBV INFECTION

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Journal of Systems Science & Complexity 2010年第6期23卷 1221-1230页

作者： Yu zheng Lequan MIN Yu JI Yongmei SU Yang kuang Information Engineering School University of Science and Technology Beijing Beijing 100083 China. Mathematics and Physics School University of Science and Technology Beijing Beijing 100083 China. Department of Mathematics and Statistics Arizona State University Temp AZ 85287-1804 USA.

In this paper, the authors first show that if Ro ≤1, the infection free steady state is globally attractive by using approaches different from those given by Min, et a1.（2008）. Then the authors prove that if Ro 〉 1, the endemic steady state is also globally attractive. Finally, based on a patient＇s clinical HBV DNA data of anti-HBV infection with drug lamivudine, the authors establish an ABVIM. The numerical simulations of the ABVIM axe good in agreement with the clinical data.

关键词： Basic infection reproduction number clinical data simulation equilibrium point global stability HBV infection.

Retransmission in the network-coding-based packet network

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第7期11卷 544-554页

作者： zheng WANG Hui-fang CHEN Lei XIE kuang WANG Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Laboratory of Information Network Technology Hangzhou 310027 China

In this paper, retransmission strategies of the network-coding-based packet network are investigated. We propose two retransmission strategies, the packet-loss-edge-based retransmission strategy (PLERT) and the minimum retransmission strategy (MRT), which focus on optimizing the retransmission efficiency without the constraint on the encoding field size. We compared the performances of the proposed retransmission strategies with the traditional automatic repeat-request (ARQ) strategy and the random retransmission strategy. Simulation results showed that the PLERT strategy works well when the packet loss rate is small. Among these retransmission strategies, the performance of the MRT strategy is the best at the cost of the high complexity that is still polynomial. Furthermore, neither of the proposed strategies is sensitive to the encoding field size.

关键词： Generation Network coding Packet network Retransmission

3D fluorescence emission difference microscopy based on spatial light modulator

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Journal of Innovative Optical Health Sciences 2016年第3期9卷 83-92页

作者： Guangyuan Zhao Zihao Rong Cuifang kuang Cheng zheng Xu Liu State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang University Hangzhou 310027P.R.China

We report three-dimensional fluorescence emission difference(3D-FED)microscopy using a spatial light modulator(SLM).Zero phase,0–2vortex phase and binary 0-pi phase are loaded on the SLM to generate the corresponding solid,doughnut and z-axis hollow excitation spot,*** technique achieves super-resolved image by subtracting three di®erently acquired images with proper subtractive *** theoretical analysis and simulation tests are proceeded to testify the performance of ***,the improvement of lateral and axial resolution is demonstrated by imaging 100 nm°uorescent *** experiment yields lateral resolution of 140 nm and axial resolution of approximate 380 nm.

关键词： Super-resolution fluorescence imaging 3D-FED microscopy spatial light modulator

One-step synthesis of thermally stable artificial multienzyme cascade system for efficient enzymatic electrochemical detection

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Nano Research 2019年第12期12卷 3031-3036页

作者： Xiqing Cheng Jinhong Zhou Jiayu Chen Zhaoxiong Xie Qin kuang Lansun zheng State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materialsand Department of ChemistryCollege of Chemistry and Chemical Engineering Xiamen UniversityXiamen 361005China Pen-Tung Sah Institute of Micro-Nano Science and Technology Xiamen UniversityXiamen 361005China

Recently,metal-organic framework(MOF)-based multienzyme systems integrating different functional natural enzymes and/or nanomaterial-basedartificial enzymes are attracting increasing attention due to their high catalytic efficiency and promising application in *** controllable integration of enzymes or nanozymes within MOFs is crucial for achieving efficient cascade catalysis and high ***,we report a facile electrochemical assisted biomimetic mineralization strategy to prepare an artificial multienzyme system for efficient electrochemicaldetection of *** using the G0x@Cu-MOF/copper foam(G0x@Cu-MOF/CF)architecture as a proof of concept,efficientenzyme immobilization and cascade catalysis were achieved by in situ encapsulation of glucose oxidase(GOx)within MOFs layer grown onthree-dimensional(3D)porous conducting CF via a facile one-step electrochemical assisted biomimetic mineralization *** to thebio-electrocatalytic cascade reaction mechanism,this well-designed GOx@Cu-MOF modified electrode exhibited superior catalytic activityand thermal stability for glucose ***,the activity of GOx@Cu-MOF/CF still remained at ca.80%after being incubated at 80℃.In sharp contrast,the activity of the unprotected electrode was reduced to the original 10%after the same *** design strategypresented here may be useful in fabricating highly stable enzyme@MOF composites applied for efficient photothermal therapy and otherplatform under high temperature.

关键词： metal-organic frameworks artificial multienzyme electrochemical assisted biomimetic mineralization glucose detection thermal stability