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Procyanidins Inhibit Tumor Angiogenesis by Crosslinking Extracellular Matrix

Chinese Journal of Cancer Research 2011年第2期23卷 99-106页

作者： wan-yin zhai Chun-ping Jia Hui Zhao Yuan-sen Xu State Key Lab of Transducer Technology Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200068 China Graduation School Chinese Academy of Sciences Beijing China Biomaterials and Tissue Engineering Research Center Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai China

Objective： Procyanidins （PC） are widely available natural polyphenols. The present study is designed to investigate if PC can inhibit angiogenesis in lung adenocarcinoma xenografts through crosslinking vascular extracellular matrix （ECM） and preventing proteolysis by matrix metalloproteinases （MMPs）. Methods： Using the in vitro MMP-2 proteolysis and in vivo subcutaneous implantation models, we investigated if PC crosslinking inhibits MMP-mediated proteolysis. Using a cultured cell detachment assay, an in vitro angiogenesis assay, and a cell proliferation assay, we investigated if PC inhibits MMP-2-mediated endothelial cell detachment, angiogenesis, and cell proliferation, respectively. Using tumor xenografts, we evaluated if PC can inhibit growth of lung adenocarcinoma. Results： PC crosslink vascular ECM proteins, protecting them against proteolysis by MMPs in vitro and in vivo, protecting cultured human umbilical vein endothelial cells from detachment by MMP-2, and inhibiting in vitro angiogenesis. However, PC （0.75-100 μg/mL） did not inhibit vascular and tumor cells proliferation. PC injections （30 mg PC/kg bodyweight） in situ had anticancer effects on xenografts of lung adenocarcinoma, most likely by inhibiting angiogenesis during ECM proteolysis by MMPs. Conclusion： The results suggest that PC may be important MMP inhibitors that can be used as therapeutic anticancer agents.

关键词： Procyanidins Crosslinking Extracellular matrix Matrix metalloproteinases Angiogenesis

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Research on electromagnetic relay's dynamic characteristics disturbed by uniform static magnetic field

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 577-582页

作者： Guo-fu zhai Qi-ya wanG wan-bin REN Military Apparatus Research Institute Harbin Institute of Technology Harbin 150001 China

Electromagnetic relay is a widely used apparatus which usually works in a magnetic disturbance environment. To evaluate its electromagnetic compatibility (EMC) in a static magnetic field, dynamic characteristics of a clapper relay in a uniform static magnetic field situation based on the finite element method (FEM) is studied. Influences of the magnetic field on dynamic parameters (delay time, pick-up time, end pressure, and final velocity) as well as a situation in which the relay cannot function normally are analyzed. Simulation reveals that the external magnetic field which weakens the relay’s air-gap field has a greater influence on the relay’s dynamic parameters than the one strengthening the field. The validity of the simulation is verified by measured results of coil current and armature displacement.

关键词： Dynamic characteristics Uniform static magnetic field Electromagnetic relay Finite element method (FEM) Electromagnetic compatibility (EMC)

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Relevant experience learning:A deep reinforcement learning method for UAV autonomous motion planning in complex unknown environments

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Chinese Journal of Aeronautics 2021年第12期34卷 187-204页

作者： Zijian HU Xiaoguang GAO Kaifang wan Yiwei zhai Qianglong wanG School of Electronic and Information Northwestern Polytechnical UniversityXi'an 710129China

Unmanned Aerial Vehicles(UAVs)play a vital role in military *** a variety of battlefield mission scenarios,UAVs are required to safely fly to designated locations without human ***,finding a suitable method to solve the UAV Autonomous Motion Planning(AMP)problem can improve the success rate of UAV missions to a certain *** recent years,many studies have used Deep Reinforcement Learning(DRL)methods to address the AMP problem and have achieved good *** the perspective of sampling,this paper designs a sampling method with double-screening,combines it with the Deep Deterministic Policy Gradient(DDPG)algorithm,and proposes the Relevant Experience Learning-DDPG(REL-DDPG)*** REL-DDPG algorithm uses a Prioritized Experience Replay(PER)mechanism to break the correlation of continuous experiences in the experience pool,finds the experiences most similar to the current state to learn according to the theory in human education,and expands the influence of the learning process on action selection at the current *** experiments are applied in a complex unknown simulation environment constructed based on the parameters of a real *** training experiments show that REL-DDPG improves the convergence speed and the convergence result compared to the state-of-the-art DDPG algorithm,while the testing experiments show the applicability of the algorithm and investigate the performance under different parameter conditions.

关键词： Autonomous Motion Planning(AMP) Deep Deterministic Policy Gradient(DDPG) Deep Reinforcement Learning(DRL) Sampling method UAV

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Mode coupling in converging Richtmyer-Meshkov instability of dual-mode interface

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Acta Mechanica Sinica 2020年第2期36卷 356-366页

作者： Zhangbo Zhou Juchun Ding Zhigang zhai wan Cheng Xisheng Luo Advanced Propulsion Laboratory Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230026China Mechanical Engineering Physical Science and Engineering DivisionKing Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia

The converging Richtmyer-Meshkov(RM)instability on single-and dual-mode N2/SF6 interfaces is studied by an upwind conservation element and solution element *** unperturbed case is first considered,and it is found that the shocked interface undergoes a long-term deceleration after a period of uniform *** evolution of single-mode interface at the early stage exhibits an evident nonlinearity,which can be reasonably predicted by the nonlinear model of wang et al.(Phys Plasmas 22:082702,2015).During the deceleration stage,the perturbation amplitude drops quickly and even becomes a negative(phase inversion)before the reshock due to the Rayleigh-Taylor(RT)*** the reshock,the interface experiences a phase inversion again or does not,depending on the reshock *** growth of the second-order harmonic in the deceleration stage clearly reveals the competition between the RT effect and the *** dual-mode interfaces,the growth of the first mode(wavenumber k1)relies heavily on the second mode(wavenumber k2)due to the mode coupling ***,for cases where k2 is an even or odd multiple of k1,the growth of the first mode is inhibited or promoted depending on its initial amplitude sign and the phase difference between two basic waves,while for cases where k2 is a non-integer multiple of k1,the second mode has negligible influence on the first *** a systematic study,signs of perturbation amplitudes of the generated k2−k1 and k2+k1 waves are obtained for all possible dual-mode configurations,which are reasonably predicted by a modified Haan model(Phys Fluids B 3:2349-2355,1991).

关键词： Converging Richtmyer-Meshkov instability Dual-mode interface Mode coupling

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Random vibration analysis of switching apparatus based on Monte Carlo method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 422-425页

作者： zhai Guo-fu CHEN Yang-hua REN wan-bin School of Electrical Engineering and Automation Harbin Institute of Technology Harbin 150001 China

The performance in vibration environment of switching apparatus containing mechanical contact is an important element when judging the apparatus’s reliability. A piecewise linear two-degrees-of-freedom mathematical model considering contact loss was built in this work, and the vibration performance of the model under random external Gaussian white noise excitation was investigated by using Monte Carlo simulation in Matlab/Simulink. Simulation showed that the spectral content and statistical characters of the contact force coincided strongly with reality. The random vibration character of the contact system was solved using time (numerical) domain simulation in this paper. Conclusions reached here are of great importance for reliability design of switching apparatus.

关键词： Contact system Random vibration Monte Carlo simulation Matlab/Simulink

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A comparison study on interfacial properties of fluorine-bearing and fluorine-free mold flux for casting advanced high-strength steels

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Journal of Iron and Steel Research International 2022年第10期29卷 1613-1618页

作者： Jian-jun Zhang Bing-yu zhai Lei Zhang wan-lin wang Central Research Institute of Baosteel(Qingshan) Wuhan430080HubeiChina School of Metallurgy and Environment Central South UniversityChangsha410083HunanChina National Center for International Research of Clean Metallurgy Central South UniversityChangsha410083HunanChina

A comparison study on interfacial properties of a traditional fluorine-bearing(F-bearing)mold flux and a newly designed fluorine-free(F-free)mold flux to produce advanced high-strength steels(AHSSs)by compact strip production technology was *** results showed that these two kinds of mold fluxes gradually spread out on the typical AHSS substrate when slags began to melt with the increase in heating temperature,and they had a good interfacial ability between the two mold fluxes and the AHSS substrate,and there was no other interfacial reaction except the oxidization of steel substrate by the mold *** comparison,the wettability of the designed F-free mold flux with the AHSS substrate was better than that of the F-bearing mold *** reason could be explained as the addition of B_(2)O_(3) would increase the complexity and polymerization degree of the melt structure and weaken the attractive force between the ions and ionic groups,then leading to a better ***,B_(2)O_(3) is an effective flux,which can reduce the melting temperature obviously,and the surface tension of the liquid F-free mold flux would get reduced with the addition of B_(2)O_(3).

关键词： Advanced high-strength steel Mold flux Fluorine-free Interfacial property Wettability

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Safety threshold of high-speed railway pier settlement based on train-track-bridge dynamic interaction

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Science China(Technological Sciences) 2015年第2期58卷 202-210页

作者： CHEN Zhao Wei zhai wan Ming CAI Cheng Biao SUN Yu State Key Laboratory of Traction Power Southwest Jiaotong University

This paper presents a method to determine the safety threshold of bridge pier settlement in high-speed *** analytical expression of the mapping relationship between the pier settlement and the rail deformation is derived theoretically for the double block ballastless track-bridge *** adopting the superposition of the track random irregularity and the rail deformation caused by the pier settlement as the excitation inputs,the variations of vehicle dynamics indices with pier settlement are comparatively ***,the safety threshold of the bridge pier settlement is obtained according to the limit of vehicle running safety and ride comfort indices of the high-speed *** show that the dynamics indices of different trains have different sensitivities to the pier settlement,and the train CRH2C is the most sensitive one among all the types of Chinese high-speed *** passing through the bridges in common span with pier settlement at the speed of 250–350 km/h,the trains suffer the low-frequency excitations,and the vertical acceleration of car body is most sensitive to the pier settlement of all the dynamics *** the car body vertical acceleration just exceeds the allowable limit,the critical settlement value is 23.4 mm,which is much bigger than the pier differential settlement limit in the current code for Chinese high-speed railways.

关键词： high-speed railway pier settlement safety threshold dynamic characteristics train-track-bridge dynamic interaction

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The development of metal hydrides using as concentrating solar thermal storage materials

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Frontiers of Materials Science 2015年第4期9卷 317-331页

作者： Xuanhui QU Yang LI Ping LI Qi wan Fuqiang zhai State Key Laboratory for Advanced Metals and Materials Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China Energy Material & Technology Research Institute General Researct Institute for Nonferrous Metals Beijing 100088 China Departament Fisica Aplicada EETAC Universitat Politecnica de Catalunya-BarcelonaTech 08860 Castelldefels Spain

Metal hydrides high temperature thermal heat storage technique has great promising future prospects in solar power generation, industrial waste heat utilization and peak load regulating of power system. This article introduces basic principle of metal hydrides for thermal storage, and summarizes developments in advanced metal hydrides high-temperature thermal storage materials, numerical simulation and thermodynamic calculation in thermal storage systems, and metal hydrides thermal storage prototypes. Finally, the future metal hydrides high temperature thermal heat storage technique is been looked ahead.

关键词： metal hydride concentrating solar power heat storage

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Method of analyzing vibration characteristics of armature system of hermetically sealed electromagnetic relay

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 434-438页

作者： REN wan-bin CUI Li LUO Fu-biao zhai Guo-fu School of Electrical Engineering and Automation Harbin Institute qf Technology Harbin 150001 China Guilin Aerospace Electronics Company Guilin 541002 China

Published research is minimal on vibration characteristics of hermetically sealed electromagnetic relay (EMR) ex- posed to mechanical environment. The vibration characteristics of armature system, link contact system with electromagnetic system will cause EMR malfunction. The nonlinear dynamics model of armature systems was studied by considering electro- magnetic attraction force and opposite mechanical force in this paper. Angular displacements of armature under different sinu- soidal vibration conditions are solved in order to obtain the failure mode result from armature system. Vibration tests showed the presented analyzing method is suitable for EMR. The conclusions are instructive for increasing vibration resistance of armature systems of EMR, and are significant for reliability design of switch apparatus.

关键词： Hermetically sealed electromagnetic relay (EMR) Armature system Vibration characteristics Analyzing method

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Progress and Prospect of Functional Rice Researches

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Agricultural Sciences in China 2008年第1期7卷 1-9页

作者： SU Ning wan Xiang-yuan zhai Hu-qu wan Jian-min Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China State Key Laboratory of Crop Genetics and Germplasm Enhancement Nanjing Agricultural University Nanjing 210095 P.R.China

With the rapid development of economy and the increase of people＇s living standards, functional foods are being gradually embraced by consumers and have a great growth potential. Rice is the main staple food in China. It plays an important role in promoting people＇s health and in improving public nutrition, and therefore there is an ever-increasing consumer demand for rice for its functional quality. This study introduces the concept of functional rice and summarizes the current research progress on this topic and the application of breeding strategies including traditional breeding, induced mutagenesis, molecular marker-assisted selection and transgenic engineering in the research of a new generation of functional rice that posses health benefits, therapeutic values, bioreactor properties, and other unique functions. We then point out the prospect of functional rice from the point of view of social development, germplasm innovation, breeding of functional rice by biological technology and the test of active material related functional rice. We conclude that developing and marketing of functional rice is becoming a subject of great importance for research and is to be the focus of research in future.

关键词： functional rice functional rice breeding research progress

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