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World Journal of Gastroenterology 2011年第21期17卷 2674-2680页

作者： Yu liu bao-An liu Division of Basic Medicine Department ofPathology Central South University Xiangya School of Medicine Changsha 410013 Hunan Province China

AIM:To investigate the contribution of periostin in nicotine-promoted gastric cancer cell proliferation,survival,invasion,drug resistance,and epithelial-mesenchymal transition(EMT).METHODS:Gastric cancer cells were treated with nicotine and periostin protein expression was determined by *** mRNA in gastric cancer cells was silenced using small interfering RNA(siRNA) techniques and periostin gene expression was evaluated by quantitative reverse transcription-polymerase chain *** cancer cells transfected with control or periostin siRNA plasmid were compared in terms of cell proliferation using the methylthiazolyldiphenyl-tetrazolium bromide *** apoptosis was compared using annexin V-fluoresceine isothiocyanate and propidium iodine double *** invasion was determined using the Boyden chamber invasion assay,and the EMT marker Snail expression was evaluated by ***:Nicotine upregulated periostin in gastric cancer cells through a COX-2 dependent pathway,which was blocked by the COX-2-specific inhibitor *** mRNA expression was decreased by ～87.2% by siRNA in gastric cancer cells,and stable periostinsilenced cells were obtained by G418 ***-silenced gastric cancer cells exhibited reduced cell proliferation,elevated sensitivity to chemotherapy with 5-fluorouracil,and decreased cell invasion and Snail expression(P < 0.05).CONCLUSION:Periostin is a nicotine target gene in gastric cancer and plays a role in gastric cancer cell growth,invasion,drug resistance,and EMT facilitated by nicotine.

关键词： Cyclooxygenase-2 Malignant growth RNA interference Snail Smoking

Numerical analysis for the matching of the core driven compression system in a double bypass engine

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航空动力学报 2011年第5期26卷 1066-1076页

作者： ZHANG Xin liu bao-jie National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

The numerical analysis for the matching of the core driven compression system in a double bypass variable cycle engine was presented in this *** system consists of a one-stage-core driven fan stage(CDFS),an inner bypass duct and a five-stage high pressure compressor(HPC),providing two basic operating modes: the single bypass mode and the double bypass *** vanes are necessary to realize the mode switch of the *** correct matching in the double bypass mode requires a proper combination of the mass flow,total pressure ratio and blade *** work capacity of the system decreases in the double bypass mode and the pressure ratio tends to decrease more for the CDFS and the front stages of the *** overall system efficiency is higher in the double bypass *** radial distributions of aerodynamic parameters are similar in different *** notable redistribution of mass flow downstream the CDFS in the single bypass mode leads to strong radial flows and additional mixing *** absolute flow angles into the inner bypass increase for the inner span and decrease for the outer span when the system is switched from the single bypass mode to the double bypass mode.

关键词： numerical analysis aerodynamic double bypass variable cycle engine core driven compression system core driven fan stage operating mode

Numerical evaluation of tandem rotor for highly loaded transonic fan

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航空动力学报 2011年第6期26卷 1352-1361页

作者： ZHAO Bin liu bao-jie School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

Transonic tandem rotor was designed for highly loaded fan at a corrected tip speed of 381 m/s and another conventional rotor was designed as a baseline to evaluate the loading superiority of tandem rotor with three-dimensional(3-D) numerical *** aft blade solidity and its impact on total loading level were studied in *** result indicates that tandem rotor has potential to achieve higher loading level and attain favorable aerodynamic performance in a wide range of loading coefficient 0.55~0.68,comparing with the conventional rotor which produced a total pressure ratio of 2.0 and loading coefficient of 0.42.

关键词： transonic fan tandem rotor highly loaded loading coefficient numerical simulation

Reactor protection system testing for the solid fuel thorium molten salt reactor

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Nuclear Science and Techniques 2016年第5期27卷 238-246页

作者： Zhen-bao liu Ye liu Gui-Min liu Jie Hou Shanghai Institute of Applied Physics Chinese Academy of Sciences Jiading campus Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

Safety system testing is one of the most rigorous and time-consuming requirements in the verification and validation process for reactor protection systems(RPSs).This paper presents the development of a test system for the fully digital and field-programmable gate array-based RPS of the solid fuel(SF) thorium-breeding molten salt pebble bed fluoride salt-cooled reactor(TMSR),denoted as the TMSR-SF1 project,developed by the Chinese Academy of *** test system is applied to the RPS to ensure that it fully meets its designed functions and system *** first introduce the testing principles and ***,the hardware component designs and the software program development of the test system are ***,the test process and test results are discussed and summarized.

关键词：反应堆保护系统试验过程固体燃料熔盐现场可编程门阵列测试系统钍设计功能

Update of transcatheter valve treatment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第8期14卷 670-675页

作者： Xian-bao liu Jian-an WANG Cardiovascular Key Lab of Zhejiang Province Department of Cardiology the Second Affiliated Hospital School of Medicine Zhejiang University

Transcatheter valve implantation or repair has been a very promising approach for the treatment of valvular heart diseases since transcatheter aortic valve implantation (TAVI) was successfully performed in 2002. Great achievements have been made in this field (especially TAVI and transcatheter mitral valve repair-MitraClip system) in recent years. Evidence from clinical trials or registry studies has proved that transcatheter valve treatment for valvular heart diseases is safe and effective in surgical high-risk or inoperable patients. As the evidence accumulates, transcatheter valve treatment might be an alterative surgery for younger patients with surgically low or intermediate risk valvular heart diseases in the near future. In this paper, the updates on transcatheter valve treatment are reviewed.

关键词：心脏疾病临床冠状动脉调查结果

Study of modeling unsteady blade row interaction in a transonic compressor stage part 2:influence of deterministic correlations on time-averaged flow prediction

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Acta Mechanica Sinica 2012年第2期28卷 291-299页

作者： Yang-Wei liu bao-Jie liu Li-Peng Lu Group 404 National Key Laboratory of ScienceTechnology on Aero-Engine Aero-thermodynamicsSchool of Jet PropulsionBeihang University100191 BeijingChina

The average-passage equation system （APES） provides a rigorous mathematical framework for account- ing for the unsteady blade row interaction through multistage compressors in steady state environment by introducing de- terministic correlations （DC） that need to be modeled to close the equation system. The primary purpose of this study was to provide insight into the DC characteristics and the in- fluence of DC on the time-averaged flow field of the APES. In Part 2 of this two-part paper, the influence of DC on the time-averaged flow field was systematically studied; Several time-averaging computations boundary conditions and DC were conducted with various for the downstream stator in a transonic compressor stage, by employing the CFD solver developed in Part 1 of this two-part paper. These results were compared with the time-averaged unsteady flow field and the steady one. The study indicat;d that the circumferential- averaged DC can take into account major part of the unsteady effects on spanwise redistribution of flow fields in compres- sors. Furthermore, it demonstrated that both deterministic stresses and deterministic enthalpy fluxes are necessary to reproduce the time-averaged flow field.

关键词： Unsteady Blade row interaction Compressor Deterministic correlation Average-passage equation system CFD

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Electrochemical behavior and corrosion resistance of IrO2–ZrO2 binary oxide coatings for promoting oxygen evolution in sulfuric acid solution

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 264-273页

作者： bao liu Shuo Wang Cheng-yan Wang bao-zhong Ma Yong-qiang Chen School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Rare and Precious Metals Green Recycling and Extraction University of Science and Technology BeijingBeijing 100083China

In this study,we prepared Ti/IrO2–ZrO2 electrodes with different ZrO2 contents using zirconium-n-butoxide(C16H36O4Zr)and chloroiridic acid(H2IrCl6)via a sol–gel *** explore the effect of ZrO2 content on the surface properties and electrochemical behavior of electrodes,we performed physical characterizations and electrochemical *** obtained results revealed that the binary oxide coating was composed of rutile IrO2,amorphous ZrO2,and an IrO2–ZrO2 solid *** IrO2–ZrO2 binary oxide coatings exhibited cracked structures with flat regions.A slight incorporation of ZrO2 promoted the crystallization of the active component ***,the crystallization of IrO2 was hindered when the added ZrO2 content was greater than 30at%.The appropriate incorporation of ZrO2 enhanced the electrocatalytic performance of the pure IrO2 *** Ti/70at%IrO2–30at%ZrO2 electrode,with its large active surface area,improved electrocatalytic activity,long service lifetime,and especially,lower cost,is the most effective for promoting oxygen evolution in sulfuric acid solution.

关键词： electrode IrO2-ZrO2 oxygen evolution reaction electrochemical behavior corrosion resistance

Dynamic regulation of DNA methylation and histone modifications in response to abiotic stresses in plants

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Journal of Integrative Plant Biology 2022年第12期64卷 2252-2274页

作者： Yutong liu Jie Wang bao liu Zheng-Yi Xu Key Laboratory of Molecular Epigenetics of the Ministry of Education(MOE) Northeast Normal UniversityChangchun 130024China

DNA methylation and histone modification are evolutionarily conserved epigenetic modifications that are crucial for the expression regulation of abiotic stress-responsive genes in *** changes in gene expression levels can result from changes in DNA methylation and histone *** the last two decades,how epigenetic machinery regulates abiotic stress responses in plants has been extensively ***,based on recent publications,we review how DNA methylation and histone modifications impact gene expression regulation in response to abiotic stresses such as drought,abscisic acid,high salt,extreme temperature,nutrient deficiency or toxicity,and ultraviolet B *** also review the roles of epigenetic mechanisms in the formation of transgenerational stress *** posit that a better understanding of the epigenetic underpinnings of abiotic stress responses in plants may facilitate the design of more stress-resistant or-resilient crops,which is essential for coping with global warming and extreme environments.

关键词： abiotic stress DNA methylation histone modification transcriptional regulation

Morphology-structure diversity of ZnS nanostructures and their optical properties

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Rare Metals 2014年第1期33卷 1-15页

作者： Yuan-Peng Zhang Wei liu bao-Dan liu Rong-Ming Wang Department of Physics Beijing University of Aeronautics and Astronautics Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences

ZnS nanostructures with different dimensions and structure-related properties were reviewed in this paper. The crystallization of nanostructures from 0D, 1D to 3D, as well as the heterogonous counterparts, was sum- marized in the aspect of zinc blende, wurtzite structure, and their combinations. Furthermore, the structure-related energy bands and the corresponding photoelectric properties of ZnS nanostructures were also focused, in which we made a brief summary of the co-relations between photoluminescence and crystallography, especially the defectrelated luminescence properties of ZnS nanocrystal.

关键词： ZnS Multi-dimensional nanostructure Photoluminescence Energy band structure

Effects of Gully Erosion and Gully Filling on Soil Degradation in the Black Soil Region of Northeast China

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Journal of Mountain Science 2013年第5期10卷 913-922页

作者： TANG Wen-jian liu Hong-hu liu bao-yuan College of Hydrology and Water Resources Hohai University Changjiang River Scientific Research Institute Changjiang Water Resources Commission State Key Laboratory of Earth Surface Processes and Resource Ecology School of GeographyBeijing Normal University

Gully erosion has caused soil degradation and even reduced soil productivity. However, only few studies on the effects of gully erosion and artificial controlling measures on soil degradation in the Black Soil Region of Northeast China are available. Thus, this study explores the relationships between gully erosion, gully filling and soil parameters. Two sets of soil samples were collected in the field at：（1） 72 sample points in the gully erosion study area, 60 sample points in the ephemeral and classical gully erosion area （3,518 m2）, 12 sample points in the deposition zone （443 m2）, （2）1o reference points along a slope unaffected by gully erosion representing the original situation before the gully was formed. All soil samples were analyzed for gravel content （GC）, soil organic matter （SOM）, total nitrogen （TN）, available nitrogen （AN）, available phosphorus （AP）, and available potassium （AK）. The soil property values on unaffected slope were fitted by the polynomial curves as the reference values in no gully erosion area. The interpolated soil property values in gully eroded study area were compared with these polynomial curves, respectively, and then, changes of soil property values were analyzed. Gully erosion caused an increase in GC and a decrease in SOM, TN, AN, AP and AK. The change of GC, SOM, TN, AN, AP, AK was 8.8%, -9.04 g kg-1, -0.92 g kg-1, -62.28 mg kg-1, -29.61 mg kg% -79.68 mg kg-1. The soil property values in the study area were below optimal values. Thus, we concluded that gully erosion and gully filling caused both on-site and off-site soil degradation. Soil degradation area was 0.65 % of the cultivated land. In addition, it was proved that gully filling were an improper soil and water conservation measure, which seems to exacerbate the problem. Thus, it is suggested that soil where soil is deep is moved to fill the gully, and then the area around the filled gullies should be covered by grass for preventing the formation and development of the g

关键词： Deposition zone Gully erosion Ephemeral gully Classical gully Soil nutrients Gullyfilling