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Maps on Positive Cones of C^(*)-algebras

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Acta Mathematica Sinica,English Series 2023年第3期39卷 387-398页

作者： Ming Chu GAO gui mei AN Department of Mathematics Louisiana Christian UniversityPinevilleLA 71359USA School of Mathematical Sciences and LPMC Nankai UniversityTianjin 300071P.R.China

We prove that a surjective map(on the positive cones of unital C^(*)-algebras)preserves the minimum spectrum values of harmonic means if and only if it has a Jordan *-isomorphism extension to the whole *** represent weighted geometric mean preserving bijective maps on the positive cones of prime C^(*)-algebras in terms of Jordan *-isomorphisms of the *** also characterize order isomorphisms and orthoisomorphisms of the projection lattice of the von Neumann algebra of all bounded linear operators on a Hilbert space,answering an open question arisen by ***,we give a description for Fuglede-Kadison determinant preserving maps on the positive cone of a finite von Neumann algebra and improve Gaal and Nayak’s work on this topic.

关键词： Operator means preserving maps positive cones projection lattices Fuglede-Kadison Determinants

Effect of indomethacin on cell cycle proteins in colon cancer cell lines

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World Journal of Gastroenterology 2005年第11期11卷 1693-1696页

作者： mei-HuaXu gui-YingZhang DepartmentofGastroenterology XiangyaHospitalCentralSouthUniversityChangsha410008HunanProvinceChina

AIM: To studythe effect of indomethacin (IN) on human colon cancer cell line SW480 with p53 mutant and SW480transfected wild-type p53 (wtp53/SW480) in vitro and investigate molecular mechanism of anti-tumor effect of IN on colon ***: SW480 cells and wtp53/SW480 cells were treated with different concentrations of IN respectively,the expressions of CDK2, CDK4 and p21WAF1/CIP1 protein were detected by Western ***: IN gradually down-regulated the expression of CDK2, CDK4 protein of wtp53/SW480 cells in a dosedependent manner, and inhibitory effect reached the maximum level at 600 μmol/L; IN up-regulated the expression of p21WAF1/CIP1 protein in a dose-dependent manner at a certain concentration range, and the expression reached the maximum level at 400 μmol/L,and returned to the base level at 600 μmol/L. The expression of CDK2, CDK4 and p21WAF1/CIP1 protein of SW480cells did not ***: IN exerts antitumor effect partly through down regulation of the expression of CDK2, CDK4 protein and up regulation of the expression of p21WAF1/PIC1.

关键词： CDK2 CDK4 p21WAF1/CIP1 SW480 Colon cancer

Influence of multi-stage heat treatment on the microstructure and mechanical properties of TC21 titanium alloy

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 296-304页

作者： Wei Long Song Zhang Yi-long Liang mei-gui Ou College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Key Laboratory for Materials Structure and Strength of guizhou province Guizhou UniversityGuiyang 550025China National Local Joint Engineering Laboratory for High Performance Metal Structure Materials and Manufacturing Technology Guizhou UniversityGuiyang 550025China

Duplex-structured TC21 alloy samples were first solution-treated at a higher temperature in theα+βregion(940°C)with furnace cooling(FC),air cooling(AC),and water cooling(WC),followed by a second-stage solution treatment at a lower temperature in theα+βregion(900°C),and then finally aged at 590°*** effects of the morphology and quantity ofαphases on the structure and properties of the TC21 alloy after the different heat treatments were *** in-situ tensile deformation process and crack propagation behavior were observed using scanning electron microscopy(SEM).The quantity of equiaxedαphases as well as the thickness of lamellarαphases reduced,the tensile strength increased firstly and then decreased,the elongation decreased with the increasing cooling rate after the first-stage solution *** amount and size of lamellarαphases increased after the second-stage solution treatment because of sufficient diffusion of the alloying elements,thereby leading to increased tensile *** amount of dispersedαphases increased after the third-stage aging treatment owing to the increase in the nucleation rate,resulting in a noteworthy strengthening *** the third-stage aging treatment,the first-stage FC sample exhibited better mechanical properties because it contained more equiaxedαandβtrans phases than the first-stage AC and WC samples.

关键词： multi-stage heat treatment titanium alloy in-situ tension microstructure mechanical properties

Microcalorimetry studies on the antibacterial effect of crude monkshood polysaccharide

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 563-567页

作者： gui-mei LIN Lian LIU Wei SHAO School of Pharmaceutical Science Shandong University Jinan 250012 China

In this paper,crude monkshood polysaccharide was isolated from Radix Aconiti Lateralis *** effects of crude monkshood polysaccharide on Escherichia coli and Staphylococcus aureus were investigated by *** power-time curves of the bacterial growth at various concentrations (c) of crude monkshood polysaccharide were plotted with a TAM air isothermal microcalorimeter at 37 °*** growth rate constant (μ),inhibitory ratio (I),peak-height (Pm),and peak-time (tm) were *** the data,the relationship between μ and c also was *** growth rate constant μ decreased with the increasing concentrations of crude monkshood ***,Pm reduced and tm increased with increasing *** experimental results revealed that crude monkshood polysaccharide had inhibitory activity towards *** and *** obtained from our study strongly suggest that microcalorimetry is a fast,simple,and more sensitive technology that can be easily performed to study the effect of drugs on bacteria.

关键词： Crude monkshood polysaccharide Microcalorimetry Escherichia coli Staphylococcus aureus Inhibitory

Dynamic extending nonlinear H_∞ control and its application to hydraulic turbine governor

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Science China(Technological Sciences) 2007年第5期50卷 618-635页

作者： mei ShengWei gui XiaoYang SHEN Chen LU Qiang State Key Laboratory of Power System Department of Electrical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Power System Department of Electrical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Power System Department of Electrical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Power System Department of Electrical Engineering Tsinghua University Beijing 100084 China

There exists a large class of nonlinear systems with uncertainties, such as hydrau- lic turbine governors, whose robust control problem is hard to solve by means of the existing robust control approaches. For this class of systems, this work pre- sents a dynamic extending H∞ controller via both differential geometry and H∞ the- ory. Furthermore, based on differential game theory, it has been verified that the proposed control strategy has robustness in the sense that the disturbance can be attenuated effectively because the L2-gain from the disturbance input to the regu- lation output signal could be reduced to any given level. Thirdly, a robust control strategy for hydraulic turbine governor is designed according to the proposed ex- tending H∞ control method, and has been developed into a real control equipment. Finally the field experiments are carried out which show clearly that the developed control equipment can enhance transient stability of power systems more effec- tively than the conventional controller.

关键词： dynamic extending H∞ control, nonlinear system, robust control, hydraulic turbine governor

In situ deformation behavior of TC21 titanium alloy with different α morphologies(equiaxed/lamellar)

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Rare Metals 2021年第5期40卷 1173-1181页

作者： Wei Long mei-gui Ou Xi-Qin Mao Yi-Long Liang College of Materials and Metallurgy Guizhou UniversityGuiyang 550025China Key Laboratory for Materials Structure and Strength of guizhou Province Guizhou UniversityGuiyang 550025China National Local Joint Engineering Laboratory for High Performance Metal Structure Materials and Manufacturing Technology Guizhou UniversityGuiyang 550025China

To study the effect ofαphase morphology(equiaxedα(αE)/lamellarα(αL))on the in situ tensile behavior of TC21 alloy,the slip band,dislocation,crack initiation,and propagation were analyzed by scanning electron microscopy(SEM)with in situ tensile stage and transmission electron microscopy(TEM).The results show that the slip bands first concentrate in theαE phases and easily truncate at theα/βphase boundaries,whereas the slip bands move across theαlamellae in theαL *** are easily generated inαE orα/βphase boundaries with large plastic *** the quantity ofαL is more thanαE,the crack tip is more easily deflected atαphases orαclusters with different orientations,making the main crack propagation path more *** the volume fraction ratio ofαE toαL is~3:4,i.e.,the volume fraction ofαE is close to that ofαL,TC21 alloy exhibits better strength and slower crack propagation rate.

关键词： In situ tensile TC21 alloy Equiaxed Lamellar αPhase

Cramér-Rao bound for multiple parameters estimation using a polarization sensitive array

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The Journal of China Universities of Posts and Telecommunications 2012年第3期19卷 107-113页

作者： ZHENG gui-mei CHEN Bai-xiao YANG Ming-lei National Laboratory of Radar Signal Processing Xidian UniversityXi'an 710071China

In this paper, new Cramér-Rao lower bounds （CRB） of the estimates of frequencies, two-dimensional arrival angles and polarization parameters of multiple incident signals are derived for a polarization sensitive array. The incident sources have distinct carrier-frequencies, in contrast to the modeling of all sources to be at the same known carrier-frequency, which has been investigated in the existing research literature on the Cramér-Rao bounds （CRB） for polarization sensitive direction finding. The derived CRBs are compact closed-form expressions and applicable to an arbitrary array geometry. Numerical examples and analysis of some special cases provide insights into the fact that the estimation accuracy of all parameters is enhanced with the increasing signal-to-noise ratio （SNR） and number of snapshots. In addition, they are hardly influenced by the sampling frequency and independent of the initial phase of incident sources. These insights offer guidelines to the system engineer on how to improve parameters＇ estimation accuracy.

关键词： array signal processing polarization sensitive array CRB direction of arrival estimation frequency estimation

Potential application of FoldX force field based protein modeling in zinc finger nucleases design

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Science China(Life Sciences) 2011年第5期54卷 442-449页

作者： HE ZuYong mei gui ZHAO ChunPeng CHEN YaoSheng Slate Key Laboratory of Biocontrol School of Life Sciences Sun Yat-Sen University Guangzhou 510006 China Institute of Animal Sciences Guangdong Academy of Agricultural Sciences Guangzhou 510640 China College of Animal Science and Technology South China Agricultural University Guangzhou 510640 China

Engineered sequence-specific zinc finger nucleases (ZFNs) make the highly efficient modification of eukaryotic genomes ***,most current strategies for developing zinc finger nucleases with customized sequence specificities require the construction of numerous tandem arrays of zinc finger proteins (ZFPs),and subsequent largescale in vitro validation of their DNA binding affinities and specificities via bacterial *** labor and expertise required in this complex process limits the broad adoption of ZFN *** effective computational assisted design strategy will lower the complexity of the production of a pair of functional *** we used the FoldX force field to build 3D models of 420 ZFP-DNA complexes based on zinc finger arrays developed by the Zinc Finger Consortium using OPEN (oligomerized pool engineering).Using nonlinear and linear regression analysis,we found that the calculated protein-DNA binding energy in a modeled ZFP-DNA complex strongly correlates to the failure rate of the zinc finger array to show significant ZFN activity in human *** our models,less than 5% of the three-finger arrays with calculated protein-DNA binding energies lower than 13.132 kcal mol 1 fail to form active ZFNs in human *** contrast,for arrays with calculated protein-DNA binding energies higher than 5 kcal mol 1,as many as 40% lacked ZFN activity in human ***,we suggest that the FoldX force field can be useful in reducing the failure rate and increasing efficiency in the design of ZFNs.

关键词： zinc finger nuclease FoldX force field protein mutation modeling

一种近红外光谱定量分析软件预测性能评价方法

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光谱学与光谱分析 2025年第1期45卷 213-221页

作者：李蓉郝璐袁洪福何桂梅邓天龙杜彪龚丽岳欣天津科技大学海洋与环境学院天津300457 天津市滨海新区环境创新研究院天津300457 中国环境科学研究院北京100012 北京易兴元石化技有限公司北京101300 中国石油大学(北京) 北京102249

常用的多元分析模型评价指标尚缺乏评价近红外分析软件多项重要预测性能指标的能力,成为近红外光谱仪预测性能以及实际近红外应用中模型适用性评价的痛点。为此,旨在发展一种近红外定量分析软件预测性能的评价方法。以近红外测定汽油烯... 详细信息

常用的多元分析模型评价指标尚缺乏评价近红外分析软件多项重要预测性能指标的能力,成为近红外光谱仪预测性能以及实际近红外应用中模型适用性评价的痛点。为此,旨在发展一种近红外定量分析软件预测性能的评价方法。以近红外测定汽油烯烃浓度为研究对象,收集了192个国Ⅵ汽油样品,包括92#、95#和98#;采集其近红外光谱;按照GB/T 30519-2014测定其烯烃浓度作为参考值,分别使用两种不同的多元分析软件(1种是偏最小二乘(PLS)建模软件,另1种是非PLS的软件),建立了两个校正模型。研究发现,与参考值相比,PLS模型对低浓度样品预测值呈正偏差,高浓度的呈负偏差,即“均值化”现象。常用的模型预测性能评价指标尚不能评价模型预测值的均值化程度,也不能评价:(1)预测值与参考值偏差大于参考方法再现性的样本占比,(2)模型泛化能力。本文针对上述问题,提出了4项新评价指标包括均值化指数(AE)、预测偏差超限值样本占比(Ratio)、异常样本预测偏差(DAS)和孤立样品预测偏差(DIS)。综合常用的评价指标和新评价指标(共12项),对仪器选型的近红外光谱定量分析软件预测性能的评价、实际近红外分析应用中模型适用性的评价均具有实际意义,对近红外分析学术研究也具参考意义。

关键词：近红外光谱多元分析模型评价近红外分析软件评价汽油烯烃浓度