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Rotation errors in numerical manifold method and a correction based on large deformation theory

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1036-1053页

作者： ning ZHANG Xu li Qinghui jiang Xingchao liN School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing 100044China School of Civil and Architectural Engineering Wuhan UniversityWuhan 430072China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Beijing 100038China

Numerical manifold method (NMM) is an effective method for simulating block system, however, significant errors are found in its simulation of rotation problems. Three kinds of errors, as volume expansion, stress vibration, and attenuation of angular velocity, were observed in the original NMM. The first two kind errors are owing to the small deformation assumption and the last one is due to the numerical damping. A large deformation NMM is proposed based on large deformation theory. In this method, the governing equation is derived using Green strain, the large deformation iteration and the open-close iteration are combined, and an updating strategy is proposed. The proposed method is used to analyze block rotation, beam bending, and rock falling problems and the results prove that all three kinds of errors are eliminated in this method.

关键词： numerical manifold method rotation large deformation Green strain open-close iteration

桂东南地方高校特色体育项目改编的实践与方法——以州珮武术“四平天地”为例

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南京体育学院学报（自然科学版） 2014年第2期13卷 112-114,157页

作者：高会军李江宁孙庆彬玉林师范学院体育学院广西玉林537000 玉林师范学院音乐与舞蹈学院广西玉林537000

运用文献资料法、访谈法和逻辑推理法,通过桂东南高等学府的玉林师范学院引入州珮武术"四平天地",并将其作为特色体育项目的研究,实践表明:"四平天地"套路改编并成为高校特色体育课程,可极大地提高大学生的学习兴趣,使之更容易地被接受... 详细信息

运用文献资料法、访谈法和逻辑推理法,通过桂东南高等学府的玉林师范学院引入州珮武术"四平天地",并将其作为特色体育项目的研究,实践表明:"四平天地"套路改编并成为高校特色体育课程,可极大地提高大学生的学习兴趣,使之更容易地被接受和普及推广。这不仅是地方高校突出其地域性办学特点的需要,也是加强民间传统武术现代传承自身改革与创新的需要。

关键词：桂东南地方高校特色体育州珮武术

The Effect of Topologies and Refilling Short-chain PEG on Protein Adsorption

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Chinese Journal of Polymer Science 2023年第12期41卷 1879-1888,I0007页

作者： Chi li Jia-ning Zhang Jing Jin Wei jiang State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

PEGylation is the gold standard for constructing protein resistance ***,grafting mPEG-SH and SH-PEG-SH with varied molecular weights(Mw=5K,10K,and 20K)on a gold chip,and the subsequent lysozyme adsorptions of the PEG layers are evaluated using quartzcrystal microbalance based on dissipation(QCM-D).The lysozyme resistance depends on the features of grafting density and chain conformation,i.e.,linear and looped ***,long-chain PEG(Mw≥10K)is insufficient to form a dense layer to resist protein due to large steric ***-chain PEG(Mw=1K)with linear and looped structures is used to refill onto the long-chain PEG layer to increase the grafting density of PEGs and improve protein *** refilling process and the subsequent protein adsorption depend on conformation rather than the density of the long-chain PEG ***,the long-chain PEG looped substrates significantly improve protein resistance,attributing to the high viscoelasticity of the looped substrate and an increase in grafting density after ***,refilling short-chain PEG improves protein resistance and the substrate conformation-dependence gives insight into the impact of topology,providing new ideas for how to increase chain density and select suitable topology to resist protein adsorption and demonstrating a potential application in biomedical fields.

关键词： Poly(ethylene glycol) Refilling Protein adsorption Conformation QCM-D

Clustering compressed sensing based on image block similarities

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The Journal of China Universities of Posts and Telecommunications 2014年第4期21卷 68-76页

作者： li Wei-wei jiang Ting WANG ning Key Laboratory of Universal Wireless Communication Beijing University of Posts and Telecommunications

Compressed sensing （CS） algorithm enables sampling rates significantly under classical Nyquist rate without sacrificing reconstructed image quality. It is known that, a great number of images have many similar areas which are composed by the same number of grayscale or color. A new CS scheme, namely clustering compressed sensing （CCS）, was proposed for image compression, and it introduces clustering algorithm onto framework of CS based on similarity of image blocks. Instead of processing the image as a whole, the image is firstly divided into small blocks, and then the clustering algorithm was proposed to cluster the similar image blocks. Afterwards, the optimal public image block in each category is selected as the representative for transmission. The discrete wavelet transform （DWT） and Gaussian random matrix are applied to each optimal public image block to obtain the random measurements. Different from equal measurements, the proposed scheme adaptively selects the number of measurements based on different sparsity of image blocks. In order to further improve the performance of the CCS algorithm, the unequal-CCS algorithm based on the characteristics of wavelet coefficients was proposed as well. The low frequency coefficients are retained to ensure the quality of reconstructed image, and the high frequency coefficients are compressed by the CCS algorithm. Experiments on images demonstrate good performances of the proposed approach.

关键词： CS DWT clustering algorithm

Effect of precipitates on high-temperature strength and irradiation behavior of vanadium-based alloys

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Journal of Iron and Steel Research International 2018年第12期25卷 1270-1277页

作者： Shao-ning jiang li-qun Xu Fa-rong Wan School of Mechanical and Automotive Engineering Qilu University of Technology (Shandong Academy of Science) Jinan 250353ShandongChina School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

The formation of precipitates and their effect on mechanical properties and irradiation damage in V-4CraTi alloys have been investigated using transmission electron microscope,high-temperature tensile tests and high-voltage electron microscope (HVEM).V-4Cr-4Ti alloys were aged for 20-40 h at 873 K,and extremely fine precipitates were produced during the aging process,which coarsened with aging *** results of high-temperature (773,873 and 973 K)tensile tests showed an increase in strength with increasing aging time (i.e:,increasing size of precipitates)while a decrease in the uniform *** was evidence that presence of precipitates strengthened V-4Cr-4Ti *** situ HVEM observations showed that the precipitates restricted the growth rate of dislocation loops induced during electron irradiation at 773 *** interactions between precipitates and irradiation-induced dislocation loops were *** presence of particles alleviated the increase in irradiation hardening up to an irradiation dose of 3.42 dpa (displacement per atom).The precipitates shrank in size during electron irradiation,which was due to the dissolution of constituent atoms of the precipitates into the alloy matrix.

关键词： Aging Precipitate strengthening Electron irradiation Irradiation defect Dislocation loop

Lycopene exerts anti-inflammatory effect to inhibit prostate cancer progression

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Asian Journal of Andrology 2019年第1期21卷 80-85页

作者： li-ning jiang Ya-Bin liu Bing-Hui li Department of Surgery II Fourth Hospital of Hebei Medical UniversityShijiazhuang 050011China Department of Urology Surgery I Cangzhou Central Hospita Cangzhou 061000China

Lycopene is a natural compound that alleviates oxidative stress and inflammation,exerting therapeutic effects in a number of *** aim of this study is to investigate the efficacy of lycopene in inhibiting prostate *** viability assays indicated the dose-and time-dependent toxicity of lycopene in prostate cancer *** V/propidium iodide double-staining assays revealed the strong apoptotic effects of *** levels of inflammatory factors,including interleukin-1 (ILl),IL6,ILS,and tumor necrosis factor-α(TNF-α),in lycopene-treated cells were also reduced by lycopene *** the increasing dose of lycopene,the survival of mice bearing prostate cancer xenografts was significantly improved (P <0.01),and the tumor burden was significantly reduced (P <0.01).Our results indicate that lycopene is a promising chemotherapy drug,which inhibits prostate cancer progression by suppressing the inflammatory response.

关键词： dietary supplement inflammation lycopene prostate cancer

Ballistic performance of spherical fragments penetrating PCrNi3MoV target plates

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Defence Technology（防务技术） 2024年第3期33卷 295-307页

作者： Dou Hong Wenbin li Yu Zheng Yiming li ning jiang Kebin Zhang Ministerial Key Laboratory of ZNDY Nanjing University of Science and TechnologyNanjingChina

PCrNi3MoV steel is a medium-carbon,low-alloy quenched and tempered steel that finds its applications in military gun barrels due to the high wear resistance and ablation *** study the penetration and failure modes of PCrNi3MoV plates impacted by tungsten spheres,tungsten spheres of various diameters(5 mm,8 mm,and 10 mm)were used to impact PCrNi3MoV steel plates with thicknesses of 6 mm,9 mm,and 14 *** penetration performance of the spheres was analyzed for different velocities,and the ultimate penetration velocity of the plate was *** was found that the primary failure modes of the PCrNi3MoV plate were compression pitting failure and shear *** the dimensional analysis method,a relationship between the bulge height of the steel plate and the fragment velocity,an equation for the ultimate penetration velocity,and a relationship between the target penetration energy and the fragment velocity were ***,a projectile-target action index was proposed to describe the process of tungsten spheres with different velocities impacting target *** results suggested that under the same thickness of the target plate,a larger-diameter fragment required more kinetic energy to obtain the same ultimate penetration effect as a smaller-diameter *** equations obtained through dimensional analysis predicted values that agreed well with experimental values,indicating that these equations can be applied to engineering applications.

关键词： Impact damage Ultimate penetration velocity Bulge height Target penetration energy Failure modes

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干热岩用耐高温钻井液关键技术及进展

探矿工程（岩土钻掘工程） 2018年第10期45卷 52-56页

作者：单文军陶士先蒋睿李艳宁北京探矿工程研究所北京100083

干热岩(HDR)是一种可再生绿色清洁能源,其勘探开发具有埋藏深,地层破碎,压力异常,井温梯度高,孔底温度高(通常大于200℃)等特点,在钻井过程中易出现钻井液漏失量大,孔壁失稳掉块卡钻等问题。本文通过分析干热岩耐高温钻井液关键技术难点... 详细信息

干热岩(HDR)是一种可再生绿色清洁能源,其勘探开发具有埋藏深,地层破碎,压力异常,井温梯度高,孔底温度高(通常大于200℃)等特点,在钻井过程中易出现钻井液漏失量大,孔壁失稳掉块卡钻等问题。本文通过分析干热岩耐高温钻井液关键技术难点:处理剂及体系抗温问题、起泡问题、漏失、井壁失稳等问题。同时通过对国内外目前干热岩用耐高温钻井液体系进展及应用情况介绍,开展干热岩钻探耐高温钻井液技术发展方向研究,以期对推动我国干热岩资源勘探开发提供有效的技术支撑。

关键词：干热岩钻井抗高温钻井液井壁稳定流变性能

Downregulation of the nucleosome-binding protein 1 （NSBP1） gene can inhibit the in vitro and in vivo proliferation of prostate cancer cells

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Asian Journal of Andrology 2010年第5期12卷 709-717页

作者： ning jiang li-Qun Zhou Xiao-Yu Zhang Department of Urology Peking University First Hospital Beijing 100034 China The Institute of Urology Peking University Beijing 100034 China National Urological Cancer Center Beijing 100034 China

This studay is to construct a lentiviral vector harbouring an RNA interference （RNAi） sequence that targets the gene encoding the human high-mobility group nucleosomal binding protein 1 （NSBP1）; to study its role in inducing G2/M phase arrest and apoptosis in prostate cancer （PCa） DU145 cells; and to assess the effect of its knockdown on cell proliferation in vitro and in vivo. RNAi was applied to knock down NSBP1 expression in the PCa cell line DU145 by lentiviral plasmids producing an NSBP1 small hairpin RNA. After NSBP1 knockdown in DU145 cells, the growth rate of cells was analyzed by MTT, and G2/M cell cycle arrest and apoptosis were assessed using a FAC- Scalibur flow cytometer. Tumour growth was assessed in nude mice. The mRNA and protein expression levels of NSBP1, cyclin B1 and Bcl-2 were analysed in vitro and in vivo by reverse-transcriptase polymerase chain reaction and Western blotting. Knockdown of NSBP1 resulted in a 22.6% decrease in the growth rate of cells compared with the PscNC lentivirus control cells at 96 h, decreased tumour growth in nude mice, and the induction of Gz/M cell cycle arrest （8.78%） and apoptosis （2.19-fold）. Consistent with the cell cycle arrest and apoptosis, the mRNA and protein expression levels of cyclin B 1 and Bcl-2 were decreased. In conclusion, knockdown of NSBP 1 causes a statistically significant inhibition of the in vitro and in vivo growth of the PCa cell line DU145. Growth suppression is at least partially due to NSBP1 knockdown-induced Gz/M cell cycle arrest and apoptosis. The present data provide the evidence that the NSBP1 knockdown-induced G2/M phase arrest and apoptosis may result from negative regulation of cyclin B 1 and Bcl-2 by NSBP1, with the resulting reduced expression of these proteins.

关键词： apoptosis NSBP 1 proliferation prostate cancer RNA interference