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聚乙二醇单分子的界面扩散:荧光关联光谱与单分子轨迹追踪测量的一致性

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中国科学：化学 2023年第4期53卷 762-767页

作者：李卓陈阔侯天昊杨京法赵江北京分子科学国家研究中心中国科学院化学研究所北京100190 中国科学院大学北京100049

高分子表界面的扩散运动在决定体系流变学性质、界面化学反应速率、相分离及其动力学、生物功能与信号传导等方面发挥着关键作用,因而,有效、准确地测量表界面处单个高分子的扩散运动具有十分重要的意义.本文以荧光关联光谱、单分子荧... 详细信息

高分子表界面的扩散运动在决定体系流变学性质、界面化学反应速率、相分离及其动力学、生物功能与信号传导等方面发挥着关键作用,因而,有效、准确地测量表界面处单个高分子的扩散运动具有十分重要的意义.本文以荧光关联光谱、单分子荧光轨迹追踪技术为手段,以吸附于固液界面的聚乙二醇(PEO)分子为模型体系,对上述两种研究方法进行了详细的比较.结果表明,虽然两种方法原理不同,覆盖的时间窗口不同,测量空间范围不同,但是在合适的测量时间窗口内对理想界面(水/硅烷化单晶薄膜的界面)处的PEO单分子扩散运动进行测量,获得了一致的扩散系数结果,表明了两种研究方法对理想界面处单分子扩散测量的准确性与可靠性.

关键词：界面扩散荧光关联光谱单分子轨迹追踪关联函数方均位移

Pse-in-One 2.0: An Improved Package of Web Servers for Generating Various Modes of Pseudo Components of DNA, RNA, and Protein Sequences

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Natural Science 2017年第4期9卷 67-91页

作者： Bin Liu Hao Wu kuo-chen Chou School of Computer Science and Technology Harbin Institute of Technology Shenzhen Graduate School Shenzhen China Key Laboratory of Network Oriented Intelligent Computation Harbin Institute of Technology Shenzhen Graduate School Shenzhen China Gordon Life Science Institute Bostom Massachusetts USA Center for Informational Biology University of Electronic Science and Technology of China Chengdu China Center of Excellence in Genomic Medicine Research (CEGMR) King Abdulaziz University Jeddah KSA

Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and comprehensive as suggested by many users, the updated package has incorporated 23 new pseudo component modes as well as a series of new feature analysis approaches. It is available at http://***/Pse-in-One2.0/. Moreover, to maximize the convenience of users, provided is also the stand-alone version called “Pse-in-One-Analysis”, by which users can significantly speed up the analysis of massive sequences.

关键词： Pseudo Components DNA Sequences RNA Sequences Protein Sequences

Fabrication and Characterization of Poly(Styrene-Butadiene-Styrene)/Thermoplastic Polyurethane Blends

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Journal of Materials Science and Chemical Engineering 2021年第2期9卷 1-10页

作者： Yuhsin Tsai Mu-chen kuo Jyh-Horng Wu School of Chinese Medicine China Medical University Taiwan Department of Materials Engineering Kun Shan University Taiwan Division of Polymer Research Industrial Technology Research Institute Taiwan

This investigation presents thermoplastic elastomers (TPEs) based on poly (styrene-butadiene-styrene) (SBS) and thermoplastic polyurethane (TPU) materials were prepared with varying compositions. A series of works were conducted on the relationships between rheological, optical properties, morphology, mechanical properties, abrasion resistance and thermostability given. The results showed that the shear viscosity of SBS not obvious effect with TPU content. The optical properties of the SBS/TPU blend that its uniform transparency. The morphology characteristics indicating the phase diversion and the variation in the size of the SBS domains from large to small as the TPU contents increased, with heterogeneous domain dispersions. Additionally, the mechanical properties, abrasion resistance and thermal resistance are improved as the amount of added TPU is increased, suggesting that the blending of SBS with TPU is consistent with the compound rule.

关键词： Thermoplastic Elastomers Poly(Styrene-Butadiene-Styrene) Thermoplastic Polyurethane

全双工主动窃听非正交多址接入系统智能超表面辅助物理层安全传输技术

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电子与信息学报 2024年第3期46卷 798-807页

作者：阔永红曹琳吕璐贺冰涛陈健西安电子科技大学通信工程学院西安710071

针对全双工被动窃听和主动干扰攻击下的多用户非正交多址接入(NOMA)系统,该文提出一种智能超表面(RIS)辅助的鲁棒波束赋形方案以实现物理层安全通信。考虑在仅已知窃听者统计信道状态信息的条件下,以系统传输中断概率和保密中断概率作... 详细信息

针对全双工被动窃听和主动干扰攻击下的多用户非正交多址接入(NOMA)系统,该文提出一种智能超表面(RIS)辅助的鲁棒波束赋形方案以实现物理层安全通信。考虑在仅已知窃听者统计信道状态信息的条件下,以系统传输中断概率和保密中断概率作为约束,通过联合优化基站发射波束赋形、RIS相移矩阵、传输速率和冗余速率,来最大化系统的保密速率。为解决上述多变量耦合非凸优化问题,提出一种有效的交替优化算法得到联合优化问题的次优解。仿真结果表明,所提方案可实现较高的保密速率,且通过增加RIS反射单元数,系统保密性能更佳。

关键词：智能超表面非正交多址接入物理层安全波束赋形

Prediction of protein folding rates from primary sequence by fusing multiple sequential features

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Journal of Biomedical Science and Engineering 2009年第3期2卷 136-143页

作者： Hong-Bin Shen Jiang-Ning Song kuo-chen Chou Bioinformatics Center Institute for Chemical Research Kyoto University Gokasho Uji Kyoto 611-0011 Japan Gordon Life Science Institute 13784 Torrey Del Mar Drive San Diego California 92130 USA. Institute of Image Processing & Pattern Recognition Shanghai Jiaotong University 800 Dongchuan Road Shanghai 200240 China

We have developed a web-server for predicting the folding rate of a protein based on its amino acid sequence information alone. The web- server is called Pred-PFR (Predicting Protein Folding Rate). Pred-PFR is featured by fusing multiple individual predictors, each of which is established based on one special feature derived from the protein sequence. The ensemble pre-dictor thus formed is superior to the individual ones, as demonstrated by achieving higher correlation coefficient and lower root mean square deviation between the predicted and observed results when examined by the jack-knife cross-validation on a benchmark dataset constructed recently. As a user-friendly web- server, Pred-PFR is freely accessible to the public at ***/bioinf/Folding Rate/.

关键词： Protein Folding Rate Ensemble Predictor Fusion Approach Web-Server Pred-PFR

Use Chou’s 5-Steps Rule to Predict Remote Homology Proteins by Merging Grey Incidence Analysis and Domain Similarity Analysis

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Natural Science 2020年第3期12卷 181-198页

作者： Weizhong Lin Xuan Xiao Wangren Qiu kuo-chen Chou Computer Department Jing-De-Zhen Ceramic Institute Jing-De-Zhen China Gordon Life Science Institute Boston MA 02478 USA

Detecting remote homology proteins is a challenging problem for both basic research and drug development. Although there are a couple of methods to deal with this problem, the benchmark datasets based on which the existing methods were trained and tested contain many high homologous samples as reflected by the fact that the cutoff threshold was set at 95%. In this study, we reconstructed the benchmark dataset by setting the threshold at 40%, meaning none of the proteins included in the benchmark dataset has more than 40% pairwise sequence identity with any other in the same subset. Using the new benchmark dataset, we proposed a new predictor called “dRHP-GreyFun” based on the grey modeling and functional domain approach. Rigorous cross-validations have indicated that the new predictor is superior to its counterparts in both enhancing success rates and reducing computational cost. The predictor can be downloaded from https://***/jcilwz/dRHP-GreyFun.

关键词： Remote Homology Proteins Grey Model Domain Similarity Chou’s 5-Steps Rules

Wenxiang: a web-server for drawing wenxiang diagrams

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Natural Science 2011年第10期3卷 862-865页

作者： kuo-chen Chou Wei-Zhong Lin Xuan Xiao 不详

The wenxiang diagram was proposed to represent α-helices in a 2D (two dimensional) space (Chou, K.C., Zhang, C.T., Maggiora, G.M. Proteins: Struct., Funct., Genet., 1997, 28, 99-108). It has the capacity to provide more information in a 2D plane about each of the constituent amino acid residues in an α-helix, and is particularly useful for studying and analyzing amphiphilic helices. To meet the increasing requests for getting the program of generating wenxiang diagrams, a user-friendly web-server called “Wenxiang” has been established. It is accessible to the public at the web-site http://***/wenxiang2 or http://***/bioinfo/wenxiang2. Further- more, for the convenience of users, here we provide a step-to-step guide for how to use the Wenxiang web-server to generate the desired wenxiang diagrams.

关键词： Amphiphilic Helix Helix-Helix Interaction Hydrophobic Hydrophilic 2D Diagram Wenxiang Diagram Helical Wheel Diagram

基于聚类分析的土壤重金属分体式LIBS检测方法研究

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光谱学与光谱分析 2024年第9期44卷 2506-2513页

作者：关丛荣梁帅陈吉文王占扩北方工业大学北京100144

土壤是人类赖以生存的物质基础,它的特性与人们的生产生活密切相关,传统土壤重金属检测方法如原子吸收光谱法、电感耦合等离子体质谱法分析能力较弱且价格昂贵,因此亟需一种开发低成本易操作的土壤多种元素同时定量分析方法。激光诱导... 详细信息

土壤是人类赖以生存的物质基础,它的特性与人们的生产生活密切相关,传统土壤重金属检测方法如原子吸收光谱法、电感耦合等离子体质谱法分析能力较弱且价格昂贵,因此亟需一种开发低成本易操作的土壤多种元素同时定量分析方法。激光诱导击穿光谱(LIBS)技术因其分析快速、多元素同时分析等优点被广泛关注,但由于其体积较大不便于携带并且大多应用于实验室分析,为了满足现场检测的需求,研制了一台分体式现场LIBS检测仪,其设计是将仪器分为探测头和机箱两部分并通过包塑管进行连接,采用微型二极管泵浦激光器,脉冲能量可达100mJ,波长1064nm,重复频率为1~10Hz;此外采用多通道高分辨率光谱仪,提高LIBS的分析性能;为了减小辐射背景干扰,利用FPGA实现μs级延迟时间功能。对其应用在11种土壤获取光谱数据,实验设置脉冲能量为100mJ,延迟时间设为1μs,积分时间2ms,每个样品采集10个不同位置的光谱,每个位置测量20次,共采集200个光谱数据,为减少噪声干扰,对每个样品的光谱数据进行均值预处理后再进行Beads算法基线校正,利用PCA主成分分析得到贡献率最大的3个主成分分量,再通过Kmeans++算法对不同地区不同类型的11种土壤进行聚类分析,将相同类别的土壤代入偏最小二乘(PLSR)算法,每个元素选取两个特征谱线以及上下各10个点来增强光谱信息,选择一种样品作为预测对Cu、Cr、Ni、Co、Cd五种土壤重金属元素进行定量分析。结果表明,与未进行聚类分析相比,此方法可明显提高元素的拟合相关系数,五种重金属元素的相关系数分别从0.953、0.992、0.989、0.982、0.99提高至0.999、0.998、0.9995、0.9965、0.993,相关系数均达到0.99及以上满足LIBS线性分析要求,其预测结果与实际含量之间的平均相对误差分别从83.45%、16.03%、22.94%、43.91%、125.768%提高至1.14%、0.99%、0.895%、1.879%、1.862%,可以发现经过聚类分析后,其预测误差大大降低,均在5%以内,具有较好的分析性能,五种元素的相关系数和预测误差相比于直接进行PLSR方法均有提升。PCA与Kmeans++结合的方法能够更准确的进行聚类,在降维后进行聚类可以减少噪声和冗余信息的影响,加快计算速度,减少异常点对聚类效果的影响提高鲁棒性。

关键词：土壤聚类分析偏最小二乘法激光诱导击穿光谱

Social capital and health literacy in Taiwan

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Health 2013年第5期5卷 898-902页

作者： Hsieh-Hua Yang Shu-chen kuo Hung-Jen Yang Jui-chen Yu Center for General Education National Defense Medical Center Taipei Taiwan Department of Health Care Administration Oriental Institute of Technology New Taipei City Taiwan Department of Industrial Technology Education National Kaohsiung Normal University Kaohsiung Taiwan National Science and Technology Museum Kaohsiung Taiwan

The argument of this study is that social capital is a key factor of health literacy. Data came from an island-wide sample. Position generator was adopted to measure social capital. A regression model is constructed to test the social capital which is known as a robust predictor of health literacy after controlling gender, age, education, income, and health communication ability. The results reveal that female, higher education, and better health communication ability are also correlated with health literacy. Implications for public health are discussed.

关键词： Social Capital Health Literacy Taiwan Area Sampling