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Adhesion behavior of endothelial progenitor cells to endothelial cells in simple shear flow

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Acta Mechanica Sinica 2011年第6期27卷 1071-1080页

作者： Xiao-Bo Gong Yu-Qing Li quan-Chao Gao bin-bin Cheng bao-Rong Shen Zhi-Qiang Yan Zong-Lai Jiang Institute of Mechanobiology and Biomedical Engineering School of Life Sciences and Biotechnology Shanghai Jiao Tong University 200240 Shanghai China Department of Engineering Mechanics School of Naval Architecture Ocean and Civil Engineering Shanghai Jiao Tong University 200240 Shanghai China

The adhesion of endothelial progenitor cells（EPCs） on endothelial cells（ECs） is one of the critical physiological processes for the regenesis of vascular vessels and the prevention of serious cardiovascular ***,the rolling and adhesion behavior of EPCs on ECs was studied numerically.A two-dimensional numerical model was developed based on the immersed boundary method for simulating the rolling and adhesion of cells in a channel *** binding force arising from the catch bond of a receptor and ligand pair was modeled with stochastic Monte Carlo method and Hookean spring *** effect of tumor necrosis factor alpha（TNF-α） on the expression of the number of adhesion molecules in ECs was analyzed experimentally.A flow chamber system with CCD camera was set up to observe the top view of the rolling of EPCs on the substrate cultivated with *** results prove that the adhesion of EPC on ECs is closely related to membrane stiff-ness of the cell and shear rate of the *** also suggests that the adhesion force between EPC and EC by P-selectin glycoprotein ligand-1 only is not strong enough to bond the cell onto vessel walls unless contributions of other catch bond are *** results demonstrate that TNF-α enhanced the expressions of VCAM,ICAM,P-selectin and E-selectin in ECs,which supports the numerical results that the rolling velocity of EPC on TNF-α treated EC substrate decreases obviously compared with its velocity on the untreated *** is found that because the adhesion is affected by both the rolling velocity and the deformability of the cell,an optimal stiffness of EPC may exist at a given shear rate of flow for achieving maximum adhesion rates.

关键词： Endothelial progenitor cell Endothelial cell Cell adhesion. Flow chamber. Immersed boundary method

A Robust and Soluble Nanopolymer based on Molecular Grid-based Nanomonomer

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Chinese Journal of Polymer Science 2017年第1期35卷 87-97页

作者： quan-you Feng Ye-long Han Meng-na Yu bin Li Ying Wei 解令海黄维 Center for Molecular Systems and Organic Devices (CMSOD) Key Laboratory for Organic Electronics and Information Displays & Institute of Advanced Materials (IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) Nanjing University of Posts & Telecommunications Nanjing 210023 China Key Laboratory of Flexible Electronics (KLOFE) & Institute of Advanced Materials (IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) Nanjing Tech University (NanjingTech) Nanjing 211816 China

Shape persistent conformations reduce the complexity of polymer materials. Herein, we propose a concept on the nanopolymer that is a nanoscale polymer chain with the repeat units of nanomonomers, In this article, a soluble organic nanopolymer of wide bandgap semiconductors was synthesized by the Yamamoto polymerization of nanogrid monomer as the repeat units with the rectangle size of -1.7 nm × 1.2 nm. The alkyl side chain substituent at 9-position of fluorenes guarantees the polygrid with excellent solubility. Tetrafluorenes in the conjugation-interrupted backbones of polygrid acts as the active light-emitting centers without obvious green band in the fluorescence spectra of the films after 10 h annealing at 180 ℃, indicating this nanopolymer exhibits excellent spectral stability. Such soluble nanopolymers will be the fifth- generation of macromolecular materials with a potential character of overall performance improvement.

关键词： Conformation Polyfluorenes Polygirds Nanopolymers Nanomaterials Stability

COMbinED EFFECT OF MODIFIED ZEOLITE 13X AND β-NUCLEATING AGENT ON IMPROVING β-CRYSTAL CONTENT AND TOUGHENING POLYPROPYLENE RANDOM COPOLYMER

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Chinese Journal of Polymer Science 2013年第11期31卷 1563-1578页

作者： Jin-hua Leng Heng Liu 何波兵 bin Yang Xian Chen Qing-quan Qin Polymer Physics and Chemistry College of ChemistrySichuan University Chengdu Product Quality Supervision and Inspection Institute Kaixian Chenjia Middle School

Although addition of β-nucleating agent directly into homo-polypropylene （PPH） is a useful method to improve ,β-crystal content and toughen PPH, polypropylene random copolymer （PPR） makes this method powerless due to its random structure and low crystallinity. In this study, the β-nucleated PPR with high β-crystal content was prepared by a novel high effective β-nucleating system which consists of β-nucleation agent （TMB-5） and modified zeolite 13X （M13X）. It was found that M13X and TMB-5 had a synergistic influence on improving β-crystal content and toughening PPR. The content of β-crystal in PPR/M13X/TMB-5 was significantly larger than the sum of that in PPR/M13X and PPR/TMB-5. Besides, fracture behavior, phase morphology and relaxation of matrix chain segments were also investigated. The results showed that M13X and TMB-5 improved the mobility of amorphous chain segments at low temperature and contributed to much energy dissipation. This work provides a powerful method to modify PPR.

关键词： Polypropylene random copolymer Zeolite fl-nucleating agent Crystallization Toughness.

Analysis of the Chinese air route network as a complex network

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Chinese Physics B 2012年第2期21卷 596-602页

作者： Cai Kai-quan Zhang Jun Du Wen-Bo Cao Xian-bin School of Electronic and Information Engineering Beihang UniversityBeijing 100083China

The air route network, which supports all the flight activities of the civil aviation, is the most fundamental infrastructure of air traffic management system. In this paper, we study the Chinese air route network （CARN） within the framework of complex networks. We find that CARN is a geographical network possessing exponential degree distribution, low clustering coefficient, large shortest path length and exponential spatial distance distribution that is obviously different from that of the Chinese airport network （CAN）. Besides, via investigating the flight data from 2002 to 2010, we demonstrate that the topology structure of CARN is homogeneous, howbeit the distribution of flight flow on CARN is rather heterogeneous. In addition, the traffic on CARN keeps growing in an exponential form and the increasing speed of west China is remarkably larger than that of east China. Our work will be helpful to better understand Chinese air traffic systems.

关键词： complex network Chinese air route network air transportation

基于区块链的车联网跨域数据安全传输系统设计

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现代电子技术 2025年第1期48卷 71-79页

作者：陈晨王斓凯施佺南通大学信息化中心江苏南通226019 南通大学交通与土木工程学院江苏南通226019

为有效应对车联网系统在数据传输过程中的安全问题,提出一种基于区块链的车联网跨域数据安全传输系统。该系统将车联网安全数据传输过程划分为注册、安全通信与数据共享三个关键环节。在注册阶段,车辆和路边单元需要通过可信机构完成注... 详细信息

为有效应对车联网系统在数据传输过程中的安全问题,提出一种基于区块链的车联网跨域数据安全传输系统。该系统将车联网安全数据传输过程划分为注册、安全通信与数据共享三个关键环节。在注册阶段,车辆和路边单元需要通过可信机构完成注册,以确保其的身份合法性;在通信阶段,为了减少路边单元与车辆频繁认证,设计了跨域认证的方法,保障数据传输的可靠性和完整性,并引入假名来保护用户隐私;在共享阶段,文中设计了基于多线程遍历共享广播森林的事务广播算法,利用广度优先搜索思想建立广播森林,并使用多线程遍历进行数据事务广播传输。实验仿真结果显示,文中方案的签名计算成本减少70%,验证计算成本减少41%;其次,在ER模型下,相比使用Gossip协议进行事务数据传输,该方案中交通数据事务总时间降低了93%;在ba模型下降低了87%。

关键词：区块链车联网身份认证密钥协商广播森林数据安全传输系统

Pollen size strongly correlates with stigma depth among Pedicularis species

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Journal of Integrative Plant Biology 2016年第10期58卷 818-821页

作者： Xiang-Ping Wang Wen-bin Yu Shi-Guo Sun Shuang-quan Huang College of Life Sciences Wuhan University Wuhan 430072China Center for Integrative Conservation Xishuangbanna Tropical Botanical Garden Chinese Academy of Sciences Mengla 666303China School of Life Sciences Central China Normal University Wuhan 430079China

Summary Darwin proposed that pollen size should be positively correlated with stigma depth rather than style length among species given that pollen tubes first enter the stigma autotrophically, then grow through the style heterotrophically. However, studies often show a posi-tive relationship between pollen size and style length. Five floral traits were observed to be correlated among 42 bumblebee-pollinated Pedicularis species （Orobancha- ceae） in which stigmas are distinct from styles. The phylogenetic independent contrast analysis revealed that pollen grain volume was more strongly correlated with stigma depth than with style length, consistent with Darwin＇s functional hypothesis between pollen size and stigma depth.

关键词： Pedicularis phylogenetic comparative analysis pollen grain volume pollen tube growth stigma depth style length trait correlation

Evolution of dielectric loss-dominated electromagnetic patterns in magnetic absorbers for enhanced microwave absorption performances

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Nano Research 2021年第11期14卷 4006-4013页

作者： Xiaogu Huang Man Qiao Xiaochi Lu Yafei Li Yabin Ma Bo Kang bin quan Guangbin Ji Institute of Advanced Materials and Flexible Electronics(IAMFE) School of Chemistry and Materials ScienceNanjing University of Information Science&TechnologyNanjing210044China College of Electronic and Optical Engineering&College of Microelectronics Nanjing University of Posts and TelecommunicationsNanjing210023China Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing210023China College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211100China

As the growing criterion of electromagnetic wave (EMW) absorption materials, micro/nano-scale magnetic materials are drawing more and more attention for their unique features compared to bulky absorbers. Generally, the complex permeability of micro/nano-scale magnetic absorbers varies in a relatively narrow range, whatever for the storage of magnetic energy or the dissipation of magnetic energy. If so, how the small variation of permeability affects the ultimate performances is still unclear. Here, a strategy of electromagnetic parameters regulation for the magnetic materials is applied to understand the loss contribution in micro/nanoscale magnetic absorbers. After analyzing the evolution of electromagnetic maps of ten ferrosoferric oxide samples, it can be found that the dissipation contribution of permeability for magnetic materials is weaker than that of permittivity, in spite of its significant role in determining the impedance matching characteristics. In summary, this work systematically explores the loss contribution in micro/nano-magnetic absorbers for the first time, which is of great importance in designing and optimizing the microwave absorption properties of magnetic absorbers.

关键词： dielectric loss magnetic loss impedance matching geometric interference microwave absorption

First order sensitivity analysis of magnetorheological fluid damper based on the output damping force

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High Technology Letters 2017年第4期23卷 446-454页

作者：孔祥东 Li bin quan Lingxiao Guo Haixin bai Ruxia College of Mechanical Engineering Yanshan University Qinhuangdao 066004 P. R. China Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Qinhuangdao 066004 P. R. China

With many features,the magnetorheological fluid( MRF) damper is widely applied in the semiactive vibration control system. And sensitivity analysis is an important method to study the influence weight of various parameters on damping force characteristics. A mathematical model of the output damping force on the MRF damper is established by the mechanism modeling method,a first order output sensitivity equation is deduced and the expression of the first order output sensitivity function is obtained. The first-order sensitivity functions of ten design parameters are solved,and the influence degree of system parameters change on the output force of MRF damper is analyzed by comparing the sensitivity index of the parameters. Two sensitivities of vibration velocity and control current are obtained through experiment to prove the other parameters sensitivity analysis conclusion by analogy verification,which provides guidance for the structure optimization design of MRF damper.

关键词： magnetorheological fluid(MRF) damper output damping force first order sensitivity analysis sensitivity index

Assessment of first-order-moment-based sample reconstruction method for design flood estimation in changing environment

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Water Science and Engineering 2023年第3期16卷 226-233页

作者： Yi-ming Hu Zhong-min Liang Yi-xin Huang Jun Wang bin-quan Li College of Hydrology and Water Resources Hohai UniversityNanjing 210098China

Estimating the design flood under nonstationary conditions is challenging. In this study, a sample reconstruction approach was developed to transform a nonstationary series into a stationary one in a future time window (FTW). In this approach, the first-order moment (EFTW) of an extreme flood series in the FTW was used, and two possible methods of estimating EFTW values in terms of point values and confidence intervals were developed. Three schemes were proposed to analyze the uncertainty of design flood estimation in terms of sample representativeness, uncertainty from EFTW estimation, and both factors, respectively. To investigate the performance of the sample reconstruction approach, synthesis experiments were designed based on the annual peak series of the Little Sugar Creek in the United States. The results showed that the sample reconstruction approach performed well when the high-order moment of the series did not change significantly in the specified FTW. Otherwise, its performance deteriorated. In addition, the uncertainty of design flood estimation caused by sample representativeness was greater than that caused by EFTW estimation.

关键词： Hydrological frequency analysis Nonstationarity Series reconstruction Uncertainty assessment Changing environment