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Role of Cu element in biomedical metal alloy design

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Rare Metals 2019年第6期38卷 476-494页

作者： Er-Lin Zhang Shan Fu ruo-Xian Wang Hai-Xia Li Ying liu Zhi-Qiang Ma Guang-Kun liu chen-Shun Zhu Gao-Wu Qin Da-Fu chen School of Materials Science and Engineering Key Laboratory for Anisotropy and Texture of MaterialsEducation Ministry of ChinaNortheastern UniversityShenyang 110819China Laboratory of Bone Tissue Engineering Beijing Laboratory of Biomedical MaterialsBeijing Research Institute of Orthopaedics and TraumatologyBeijing Jishuitan HospitalBeijing 100035China

Biomedical metals are widely used as implant materials in the human or animal body to repair organs and restore function, such as heart valves, meninges, peritoneum and artificial *** element affects the microstructure, mechanical property, corrosion resistance and wear resistance, but also influences the antibacterial and biological ***, antibacterial metal alloys have shown great potential as a new kind of biomedical materials, in which Cu has been widely used as antibacterial agent *** addition, biodegradable metal alloys, including magnesium alloy and zinc alloy, also have attracted much attention *** was also used as alloying element to adjust the degradation ***, the role of Cu in the alloy design will be very important for the development of new *** this paper, we summarized the recent research results on the Cu-containing metal alloy for biomedical application and hoped that this review would give more suggestions for the further development of biomedical metal alloy.

关键词： Cu Biomedical metal alloy Corrosion resistance Antibacterial property Biological property

Conformational Study of 8-C-glucosyl-prunetin by Dynamic NMR Spectroscopy

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Chinese Chemical Letters 2002年第7期13卷 645-648页

作者： Pei cheng ZHANG Ying Hong WANG Xin liu Xiang YI ruo Yun chen De Quan YU Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050

By means of variable temperature NMR spectra, conformation of 8-C-glucosyl prunetin, isolated from the leaves of Dalbergia hainanensis (Leguminosae), was studied. The restricted rotation around the C (sp3)-C (sp2) bond in the C-glucosides isoflavonoid results in two main conformers (syn and anti). With the help of MM calculation, the preferred conformation A has H-1 gauche to the 7-OCH3. The barrier to rotation was 18.1 kcal/mol. This result agrees with the calculated value 16.2 kcal/mol of free energy of activation for the interconversion between the conformers.

关键词： C-Glucosyl prunetin dynamic NMR MM calculation conformation.

基于动态贝叶斯博弈的工业控制网络恶意接入检测研究

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计算机科学 2025年第1期52卷 383-392页

作者：刘浩含陈泽茂武汉大学国家网络安全学院武汉430040

针对工业控制网络(Industrial Control Network, ICN)远程接入场景下未经授权访问、拒绝服务攻击、欺骗攻击以及信息披露等安全问题,通过STRIDE威胁建模方法对该场景下的潜在威胁进行分析,提出一种基于动态贝叶斯博弈的接入检测框架。... 详细信息

针对工业控制网络(Industrial Control Network, ICN)远程接入场景下未经授权访问、拒绝服务攻击、欺骗攻击以及信息披露等安全问题,通过STRIDE威胁建模方法对该场景下的潜在威胁进行分析,提出一种基于动态贝叶斯博弈的接入检测框架。该方法能够将试图接入ICN的非法、恶意请求筛选出来并阻断,同时利用持续进行的多轮博弈迭代以及SDN灵活动态的特性对策略参数进行实时调整,以防止相同恶意接入源的再次访问。仿真实验结果表明,随着博弈轮数的增加,相比于现有的两类恶意接入防御方法,该框架的检测准确性提升了3%以上,假阳性比例下降了1.2%以上,检测效率提升了14.7%以上,且具有较好的鲁棒性。

关键词：工业控制网络软件定义网络动态贝叶斯博弈恶意接入检测

Asymptotic false discovery control of the Benjamini-Hochberg procedure for pairwise comparisons

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Science China Mathematics 2025年第1期 223-252页

作者： Weidong liu Dennis Leung Qi-Man Shao School of Mathematical Sciences Shanghai Jiao Tong University School of Mathematics and Statistics University of Melbourne Department of Statistics and Data Science SICMSouthern University of Science and Technology

In a one-way analysis-of-variance(ANOVA) model,the number of pairwise comparisons can become large even with a moderate number of *** by this,we consider a regime with a growing number of groups and prove that,when testing pairwise comparisons,the Benjamini-Hochberg(BH) procedure can asymptotically control false discoveries,despite the fact that the involved t-statistics do not exhibit the wellknown positive dependence structure required for exact false discovery rate(FDR) *** Tukey's perspective that the difference between the means of any two groups cannot be exactly zero,our main result provides control over the directional false discovery rate and directional false discovery proportion.A key technical contribution of our work is demonstrating that the dependence among the t-statistics is sufficiently weak to establish the convergence result typically required for asymptotic FDR *** analysis does not rely on conventional assumptions such as normality,variance homogeneity,or a balanced design,thereby offering a theoretical foundation for applications in more general settings.

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Brain-derived neurotrophic factor and its related enzymes and receptors play important roles after hypoxic-ischemic brain damage

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Neural Regeneration Research 2021年第8期16卷 1453-1459页

作者： liu-Lin Xiong Jie chen ruo-Lan Du Jia liu Yan-Jun chen Mohammed Al Hawwas Xin-Fu Zhou Ting-Hua Wang Si-Jin Yang Xue Bai National Traditional Chinese Medicine Clinical Research Base and Western Medicine Translational Medicine Research Center Department of Cardiovascular DiseaseAffiliated Traditional Chinese Medicine HospitalSouthwest Medical UniversityLuzhouSichuan ProvinceChina Cinical and Health Sciences University of South AustraliaAdelaideAustralia Animal Zoology Department Institute of NeuroscienceKunming Medical UniversityKunmingYunnan ProvinceChina Institute of Neurological Disease Translational Neuroscience CenterWest China HospitalSichuan UniversityChengduSichuan ProvinceChina

Brain-derived neurotrophic factor(BDNF) regulates many neurological functions and plays a vital role during the recovery from central nervous system injuries. However, the changes in BDNF expression and associated factors following hypoxia-ischemia induced neonatal brain damage, and the significance of these changes are not fully understood. In the present study, a rat model of hypoxic-ischemic brain damage was established through the occlusion of the right common carotid artery, followed by 2 hours in a hypoxic-ischemic environment. Rats with hypoxic-ischemic brain damage presented deficits in both sensory and motor functions, and obvious pathological changes could be detected in brain tissues. The m RNA expression levels of BDNF and its processing enzymes and receptors(Furin, matrix metallopeptidase 9, tissuetype plasminogen activator, tyrosine Kinase receptor B, plasminogen activator inhibitor-1, and Sortilin) were upregulated in the ipsilateral hippocampus and cerebral cortex 6 hours after injury;however, the expression levels of these m RNAs were found to be downregulated in the contralateral hippocampus and cerebral cortex. These findings suggest that BDNF and its processing enzymes and receptors may play important roles in the pathogenesis and recovery from neonatal hypoxic-ischemic brain damage. This study was approved by the Animal Ethics Committee of the University of South Australia(approval No. U12-18) on July 30, 2018.

关键词： brain injury brain-derived neurotrophic factor enzyme hypoxia-ischemia receptors recovery repair

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao Lan-Sheng liu Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-Rui Ma Lan-Ying Zhang ruo-chen Lan College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

Beyond Performance of Learning Control Subject to Uncertainties and Noise: A Frequency-Domain Approach Applied to Wafer Stages

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 198-214页

作者： Fazhi Song Ning Cui Shuaiqi chen Kai Zhang Yang liu Xinkai chen Jiubin Tan IEEE the Center of Ultra-precision Optoelectronic Instrument Engineering Harbin Institute of Technology the Key Laboratory of Ultra-Precision Intelligent Instrumentation Ministry of Industry and Information Technology the State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of Technology the Center of Ultraprecision Optoelectronic Instrument Engineering Harbin Institute of Technology the Key Laboratory of UltraPrecision Intelligent Instrumentation Ministry of Industry and Information Technology the Department of Electronic and Information Systems Shibaura Institute of Technology

The increasingly stringent performance requirement in integrated circuit manufacturing, characterized by smaller feature sizes and higher productivity, necessitates the wafer stage executing a extreme motion with the accuracy in terms of nanometers. This demanding requirement witnesses a widespread application of iterative learning control(ILC), given the repetitive nature of wafer scanning. ILC enables substantial performance improvement by using past measurement data in combination with the system model knowledge. However, challenges arise in cases where the data is contaminated by the stochastic noise, or when the system model exhibits significant uncertainties, constraining the achievable performance. In response to this issue, an extended state observer(ESO) based adaptive ILC approach is proposed in the frequency *** being model-based, it utilizes only a rough system model and then compensates for the resulting model uncertainties using an ESO, thereby achieving high robustness against uncertainties with minimal modeling effort. Additionally, an adaptive learning law is developed to mitigate the limited performance in the presence of stochastic noise, yielding high convergence accuracy yet without compromising convergence speed. Simulation and experimental comparisons with existing model-based and data-driven inversion-based ILC validate the effectiveness as well as the superiority of the proposed method.

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Research progress of catalysts for direct coal liquefaction

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Journal of Energy Chemistry 2025年第1期 481-497页

作者： Wei Song Penggao liu Xinyue chen Ting Wang Chunrong He Rui Hao Kaiyu liu State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of Chemistry Xinjiang University College of Chemistry and Chemical Engineering Henan Polytechnic University Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical Engineering Central South University

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

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How machine learning informs ride-hailing services:A survey

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Communications in Transportation Research 2022年第1期2卷 289-297页

作者： Yang liu ruo Jia Jieping Ye Xiaobo Qu Department of Architecture and Civil Engineering Chalmers University of TechnologyGothenburgSweden State Key Laboratory of Automotive Safety and Energy School of Vehicle and MobilityTsinghua UniversityBeijingChina Department of Computational Medicine and Bioinformatics University of MichiganAnn ArborUnited States

In recent years,online ride-hailing services have emerged as an important component of urban transportation system,which not only provide significant ease for residents’travel activities,but also shape new travel behavior and diversify urban mobility *** study provides a thorough review of machine-learning-based methodologies for on-demand ride-hailing *** importance of on-demand ride-hailing services in the spatiotemporal dynamics of urban traffic is first highlighted,with machine-learning-based macro-level ride-hailing research demonstrating its value in guiding the design,planning,operation,and control of urban intelligent transportation ***,the research on travel behavior from the perspective of individual mobility patterns,including carpooling behavior and modal choice behavior,is *** addition,existing studies on order matching and vehicle dispatching strategies,which are among the most important components of on-line ridehailing systems,are collected and ***,some of the critical challenges and opportunities in ridehailing services are discussed.

关键词： Ride-hailing services Machine learning Traffic dynamics Individual mobility patterns