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Arabidopsis Profilin Isoforms,PRF1 and PRF2 Show Distinctive Binding Activities and Subcellular Distributions

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Journal of Integrative Plant Biology 2009年第2期51卷 113-121页

作者： feng ang Yanping Jing Zhen ang Tonglin Mao Jozef Samaj Ming Yuan Haiyun Ren State Key Laboratory of Plant Physiology and Biochemistry China Agricultural University Beijing 100094 China College of Life Sciences Beijing Normal University Beijing 100875 China College of Biological Sciences and Biotechnology Beijing Forestry University Beijing 100083 China Institute of Cellular and Molecular Botany Rheinische Friedrich-Wilhelms- University Bonn Department of Plant Cell Biology Kirschallee 1 D-53115 Bonn Germany Institute of Plant Genetics and Biotechnology Slovak Academy of Sciences Akademicka 2 SK-95007 Nitra Slovak Republic

Profilin is an actin-binding protein that shows complex effects on the dynamics of the actin cytoskeleton. There are five profilin isoforms in Arabidopsis thaliana L. However, it is still an open question whether these isoforms are functionally different. In the present study, two profilin isoforms from Arabidopsis, PRF1 and PRF2 were fused with green fuorescent protein （GFP） tag and expressed in Escherichia coil and A. thaliana in order to compare their biochemical properties in vitro and their cellular distributions in vivo. Biochemical analysis revealed that fusion proteins of GFP-PRF1 and GFP-PRF2 can bind to poly-L-proline and G-actin showing remarkable differences. GFP-PRF1 has much higher affinities for both poly-L-proline and G-actin compared with GFP-PRF2. Observations of living cells in stable transgenic A. thaliana lines revealed that 35S：：GFP-PRF1 formed a filamentous network, while 35S：：GFP-PRF2 formed polygonal meshes. Results from the treatment with latrunculin A and a subsequent recovery experiment indicated that filamentous alignment of GFP-PRF1 was likely associated with actin filaments. However, GFP-PRF2 localized to polygonal meshes resembling the endoplasmic reticulum. Our results provide evidence that Arabidopsis profllin isoforms PRF1 and PRF2 have different biochemical affinities for poly-L-proline and G-actin, and show distinctive Iocalizations in living cells. These data suggest that PRF1 and PRF2 are functionally different isoforms.

关键词： actin filaments Arabidopsis endoplasmic reticulum profilin isoforms PRF1 PRF2

Adding memory to pressure-sensitive phosphors

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Light(Science & Applications) 2019年第1期8卷 1-10页

作者： Robin R.Petit Simon E.Michels ang feng Philippe F.Smet LumiLab Department of Solid State SciencesGhent UniversityKrijgslaan 281-S19000 GentBelgium

Mechanoluminescence(ML)is the phenomenon describing the emission of light during mechanical action on a solid,leading to applications such as pressure sensing,damage detection and visualization of stress *** most cases,this mechanical action releases energy that was previously stored in the crystal lattice of the phosphor by means of trapped charge carriers.A drawback is the need to record the ML emission during a pressure *** this work,we provide a method for adding a memory function to these pressure-sensitive phosphors,allowing an optical readout of the location and intensity of a pressure event in excess of 72 h after the *** is achieved in the BaSi_(2)O_(2)N_(2):Eu^(2+) phosphor,where a broad trap depth distribution essential for the process is *** merging optically stimulated luminescence(OSL),thermoluminescence(TL)and ML measurements,the influence of light,heat and pressure on the trap depth distribution is carefully *** analysis demonstrates that mechanical action can not only lead to direct light emission but also to a reshuffling of trap *** memory effect not only is expected to lead to new pressure sensing applications but also offers an approach to study charge carrier transitions in energy storage phosphors.

关键词： luminescence occupation adding

Cyclic-delay time-reversal space-time block codes for single-carrier transmission with frequency-domain decision-feedback equalization

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Science China(Information Sciences) 2011年第9期54卷 1905-1915页

作者： feng ang,YIN QinYe & Wang HuiMing MOE Key Laboratory for Intelligent Networks and Network Security,Xi’an Jiaotong University,Xi’an 710049,China MOE Key Laboratory for Intelligent Networks and Network Security Xi’an Jiaotong University Xi’an China

Transmit diversity is an important multiple-input multiple-output (MIMO) approach to improve the transmission reliability;however,it is usually designed with maximum-likelihood *** this paper,we investigate a simple transceiver structure for single-carrier MIMO systems,in which the cyclic-delay time-reversal space-time block code (CDTR-STBC) is employed at the transmitter,and the frequency-domain decision-feedback equalization (FD-DFE) is used at the *** separate the transmit antennas into two groups,and then,encode the groups by STBC and cyclically delay the data streams within each *** processing can mitigate the impact of error-propagation and reduce the signal-to-noise ratio (SNR) loss when FD-DFE is employed,in which SNR is defined as the ratio of the received signal power over the noise power at each receive *** support our proposal,this paper also provides the performance analysis of *** is shown that the proposed scheme can achieve full diversity and full transmission rate for a MIMO system employing arbitrary ***,it has considerable performance improvement over the existing schemes.

关键词： single-carrier frequency-domain equalization cyclic delay space-time block code diversity order

VUV spectroscopic properties of rare-earth(RE=Eu,Tb and Dy)-doped A_2Zr(PO_4)_2(A=Li,Na and K) phosphates

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Journal of Rare Earths 2014年第10期32卷 946-951页

作者：林啸冯昂张志军赵景泰 Key Laboratory of Transparent Opto-Functional Inorganic Materials of Chinese Academy of Sciences Shanghai Institute of CeramicsChinese Academy of Sciences Graduate University of Chinese Academy of Sciences School of Materials Science and Engineering Shanghai University

This study fully investigated the vacuum ultraviolet excitation spectra of pure and rare-earth（RE=Eu, Tb and Dy）-doped A2Zr（PO4）2（A=Li, Na and K） phosphors. The synthesized Na and Li compounds were characterized by XRD showing two new types of phases after indexation. Although these three pure compounds had different crystal structures, they exhibited similar luminescence properties. For Eu3＋-activated samples, the broad excitation band centered at 217 nm could be attributed to the CT transition between O2–（2p6） and Eu3＋ ions. For Tb3＋-doped samples, two groups of f-d transitions were observed, where a strong broad band at 221 nm was due to the spin-allowed f-d transition. Energy transfer from O2– to Dy3＋was not observed in Dy3＋-doped phosphors, probably because it overlapped considerably with the CT transition from O2– to Zr4＋ at 187 nm.

关键词： rare-earth phosphates optical materials luminescence VUV spectra

双选择性衰落信道下的改进型频域判决反馈均衡

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西安交通大学学报 2010年第10期44卷 67-71页

作者：冯昂张莹邓科西安交通大学智能网络与网络安全教育部重点实验室西安710049

针对双选择性衰落信道下传统频域判决反馈均衡(FD-DFE)会遭受严重性能损失的问题,提出一种新的重叠保留频域判决反馈均衡(OLS-FD-DFE)算法.首先,在设计前馈滤波器时,通过对其取值范围做出约束,使得有效抽头只在指定区间内存在非0值.然后... 详细信息

针对双选择性衰落信道下传统频域判决反馈均衡(FD-DFE)会遭受严重性能损失的问题,提出一种新的重叠保留频域判决反馈均衡(OLS-FD-DFE)算法.首先,在设计前馈滤波器时,通过对其取值范围做出约束,使得有效抽头只在指定区间内存在非0值.然后,利用重叠保留法,将数据块分割为多个子块再进行频域均衡,如果子块长度小于信道相干时宽,只要在均衡每个子块时依据信道响应更新滤波器系数,就可以明显提高对信道时变的容忍度.仿真结果表明,当移动速度为100km/h时,OLS-FD-DFE算法在信噪比20dB处的误码率可以达到2×10-5,而相同情况下FD-DFE算法的误码率只能达到8×10-4.

关键词：单载波调制频域均衡重叠保留判决反馈均衡

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分层空时码分多址系统的快速联合检测算法

系统仿真学报 2008年第9期20卷 2307-2310,2315页

作者：冯昂殷勤业西安交通大学电子与信息工程学院西安710049

分层空时码分多址系统(LST-CDMA)的联合检测算法(JD)利用扩频码和信道冲击响应(CIR)卷积形成的空-时二维特征向量来进行多用户和多天线检测,能够获得优良的检测性能。但是该JD算法的复杂度非常高,针对这个问题提出了两种快速算法:近似Ch... 详细信息

分层空时码分多址系统(LST-CDMA)的联合检测算法(JD)利用扩频码和信道冲击响应(CIR)卷积形成的空-时二维特征向量来进行多用户和多天线检测,能够获得优良的检测性能。但是该JD算法的复杂度非常高,针对这个问题提出了两种快速算法:近似Cholesky分解和块-Fourier算法。为了进一步减少运算量,又利用重叠保留法(OLA)对块-Fourier算法进行改进。仿真证明,这些算法在几乎不降低检测性能的前提下,可以大幅降低计算复杂度。

关键词：分层空时码分多址联合检测 Cholesky分解块-Fourier

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船用表面桨系统万向联轴器损毁原因分析

船海工程 2021年第6期50卷 36-40页

作者：冯盎然中国船级社珠海分社广东珠海519000

针对某新型表面桨试航过程中发生无法修复的损毁故障,对万向联轴器样品碎片进行化学分析,确认故障系由端面卡簧漏装造成,对这种罕见的故障进行技术总结。

关键词：表面桨万向联轴器端面卡簧

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某主机轴瓦烧蚀与齿轮箱高弹撕裂故障分析

船海工程 2023年第S1期52卷 21-25页

作者：冯盎然中国船级社珠海分社广东珠海519000

针对高速试航过程中多次出现的轴瓦烧蚀及齿轮箱高弹脱胶撕裂故障,为更精准寻找故障原因,通过横向对比知名品牌齿轮箱、复核选型与加工精度、扭振测量等多种方法,判断高弹间隙过小、高弹与钢芯黏合强度不足和高弹有效温度偏低造成故障... 详细信息

针对高速试航过程中多次出现的轴瓦烧蚀及齿轮箱高弹脱胶撕裂故障,为更精准寻找故障原因,通过横向对比知名品牌齿轮箱、复核选型与加工精度、扭振测量等多种方法,判断高弹间隙过小、高弹与钢芯黏合强度不足和高弹有效温度偏低造成故障的可能性较大,并确定两种故障的因果关系,即高弹撕裂引起的离心力不平衡,造成主机轴瓦烧蚀。

关键词：轴瓦烧蚀高弹联轴器撕裂

重叠保留最小均方误差块线性均衡和块噪声预测算法

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西安交通大学学报 2010年第8期44卷 68-71,77页

作者：冯昂殷勤业韩玮西安交通大学智能网络与网络安全教育部重点实验室西安710049

针对以往频域均衡器无法直接应用重叠保留法的问题,提出了重叠保留最小均方误差块线性均衡和块噪声预测2种算法.在设计线性均衡器时,有效抽头被限制在一定范围内,避免了在采用重叠保留法时引入有色噪声,并且使得误码率曲线在高信噪比区... 详细信息

针对以往频域均衡器无法直接应用重叠保留法的问题,提出了重叠保留最小均方误差块线性均衡和块噪声预测2种算法.在设计线性均衡器时,有效抽头被限制在一定范围内,避免了在采用重叠保留法时引入有色噪声,并且使得误码率曲线在高信噪比区域不会发生畸变.在分层检测时,使用块噪声预测以兼容重叠保留法,从而将前馈滤波器和反馈滤波器分解为2个相互独立的模块,同时前馈滤波器恰好等于线性均衡器,因此再将重叠保留法应用于前馈滤波中,获得低复杂度和高性能的双重效果.仿真结果表明,2种算法的误码率曲线在高信噪比区域不会出现反弹,而且与不使用重叠保留法的高复杂度算法相比,分别只有大约1dB和0.3dB的信噪比损失.

关键词：重叠保留法噪声预测线性均衡