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A Construction of Multiresolution Analysis on Interval

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Acta Mathematica Sinica,English Series 2007年第4期23卷 705-710页

作者： di rong chen Dao Hong XIANG Department of Mathematics and LMIB Beijing University of Areonautics and Astronautics Beijing 100083 P. R. China

We present a concrete method of constructing multiresolution analysis on interval. The method generalizes the corresponding results of Cohen, Daubechies and Vial [Appl. Comput. Harmonic Anal., 1（1993）, 54-81]. By the use of the subdivision operator, the expressions of the constructed functions are more compact. Furthermore, the method reveals more clearly some properties of multiresolution analysis with certain approximation order.

关键词： Multiresolution analysis Refinable function Approximation order Subdivision operator

Rademacher Complexity in Neyman-Pearson Classification

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Acta Mathematica Sinica,English Series 2009年第5期25卷 855-868页

作者： Min HAN di rong chen Zhao Xu SUN Department of Applied Mathematics Beijing University of Technology Beijing 100124 P. R. China Department of Mathematics and LMIB Beijing University of Aeronautics and Astronautics Beijing 100083 P. R. China School of Applied Mathematics Central University of Finance and Economics Beijing 100081 P. R. China

Neyman-Pearson（NP） criterion is one of the most important ways in hypothesis testing. It is also a criterion for classification. This paper addresses the problem of bounding the estimation error of NP classification, in terms of Rademacher averages. We investigate the behavior of the global and local Rademacher averages, and present new NP classification error bounds which are based on the localized averages, and indicate how the estimation error can be estimated without a priori knowledge of the class at hand.

关键词： Neyman-Pearson lemma VC classes Rademacher complexity Neyman-Pearson classification

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： di-Chao chen Xie Liu Changqing Xu Da-Jian Wu Ying cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Nanoparticles for the treatment of spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1665-1680页

作者： Qiwei Yang di Lu Jiuping Wu Fuming Liang Huayi Wang Junjie Yang Ganggang Zhang chen Wang Yanlian Yang Ling Zhu Xinzhi Sun Department of Orthopedic Surgery The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Key Laboratory for Biomedical Effects of Nanomaterials and NanosafetyCAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijingChina University of Chinese Academy of Sciences BeijingChina Department of Neurosurgery The First Affiliated Hospital of Chongqing Medical UniversityChongqingChina

Spinal cord injuries lead to significant loss of motor, sensory, and autonomic functions, presenting major challenges in neural regeneration. Achieving effective therapeutic concentrations at injury sites has been a slow process, partly due to the difficulty of delivering drugs effectively. Nanoparticles, with their targeted delivery capabilities, biocompatibility, and enhanced bioavailability over conventional drugs, are garnering attention for spinal cord injury treatment. This review explores the current mechanisms and shortcomings of existing treatments, highlighting the benefits and progress of nanoparticle-based approaches. We detail nanoparticle delivery methods for spinal cord injury, including local and intravenous injections, oral delivery, and biomaterial-assisted implantation, alongside strategies such as drug loading and surface modification. The discussion extends to how nanoparticles aid in reducing oxidative stress, dampening inflammation, fostering neural regeneration, and promoting angiogenesis. We summarize the use of various types of nanoparticles for treating spinal cord injuries, including metallic, polymeric, protein-based, inorganic non-metallic, and lipid nanoparticles. We also discuss the challenges faced, such as biosafety, effectiveness in humans, precise dosage control, standardization of production and characterization, immune responses, and targeted delivery in vivo. Additionally, we explore future directions, such as improving biosafety, standardizing manufacturing and characterization processes, and advancing human trials. Nanoparticles have shown considerable progress in targeted delivery and enhancing treatment efficacy for spinal cord injuries, presenting significant potential for clinical use and drug development.

关键词： antioxidants axon regeneration biocompatible materials drug carriers nanoparticles nerve regeneration neuroinflammatory diseases neuroprotection spinal cord injury stem cells

disinfection byproducts in indoor swimming pool water: Detection and human lifetime health risk assessment

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Journal of Environmental Sciences 2023年第4期126卷 378-386页

作者： di Zhang Shengkun Dong Li chen rong Xiao Wenhai Chu State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China Southern Laboratory of Ocean Science and Engineering Key Laboratory of Water Cycle and Water Security in Southern China of Guangdong Higher Education InstituteSun Yat-sen UniversityGuangzhou 510275China

Quantification of regulated and emerging disinfection byproducts (DBPs) in swimming pool water,as well as the assessment of their lifetime health risk are limited in *** this study,the occurrence of regulated DBPs (e.g.,trihalomethanes,haloacetic acids) and emerging DBPs (e.g.,haloacetonitriles,haloacetaldehydes) in indoor swimming pool water and the corresponding source water at a city in Eastern China were *** concentrations of DBPs in swimming pool water were 1-2 orders of magnitude higher than that in source *** cancer and non-cancer risks of DBPs stemming from swimming pool water were also *** and dermal exposure were the most significant exposure routes related to swimming pool DBP cancer and non-cancer *** the first time,buccal and aural exposure were considered,and were proven to be important routes of DBP exposure (accounting for 17.9%-38.9%of total risk).The cancer risks of DBPs for all swimmers were higher than 10^(-6)of lifetime exposure risk recommended by United States Environmental Protection Agency,and the competitive adult swimmers experienced the highest cancer risk (7.82×10^(-5)).These findings provide important information and perspectives for future efforts to lower the health risks associated with exposure to DBPs in swimming pool water.

关键词： Health risk assessment Swimming pool water disinfection byproducts Multiple exposure pathway

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang Yi-De Zhang Jie chen Hai-di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Influence of oil and water media on fretting behaviour of AISI 52100 steel rubbing against AISI 1045 steel

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中国有色金属学会会刊:英文版 2004年第Z1期14卷 364-369页

作者： REN Ping-di chen Guang-xiong ZHU Min-hao ZHOU Zhong-rong The Key Laboratory of Education Ministry of China on Advanced Material Technology Southwest Jiaotong University Chengdu 610031 China

A series of fretting test were carried out using a DELTA PLINT testing system to study the influence of hydraulic oil and water on fretting behaviour of AISI 52100 steel rubbing against AISI 1045 steel. The test result shows that media hydraulic oil and water have a distinct influence on fretting behaviour of the tested materials. Medium water can lead to shifting of the partial slip regime in the fretting map from a larger displacement amplitude toward a smaller one and enlargement of the mixed slip regime, in comparison with that in ambient atmosphere. While medium hydraulic oil can result in shifting of the partial slip regime from a smaller displacement amplitude toward a larger one. In the gross slip regime, hydraulic oil and water play a positive role as lubrication media. They can clearly decrease the fretting friction coefficient between AISI 52100 and AISI 1045. The test result also demonstrates that this lubrication effect will get better with increasing displacement amplitude and that hydraulic oil is better than water for lubrication. SEM observation of the wear scars displays that the fretting wear mainly results from abrasive wear and delamination of the fretted materials when using these two kinds of substances as lubrication media.

关键词： fretting hydraulic oil water lubrication

Immobilization of laccase by Cu^(2+) chelate affinity interaction on surface modified magnetic silica particles and its use for the removal of pentachlorophenol

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Chinese Chemical Letters 2012年第2期23卷 197-200页

作者： Ying Wang di Zhang Fu rong He Xiao Chun chen The Key Laboratory of Water and Sediment Sciences Ministry of EducationSchool of EnvironmentBeijing Normal UniversityBeijing 100875China State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal UniversityBeijing 100875China Department of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Magnetic Cu^（2＋）-chelated silica particles using polyacrylamide as a metal-chelating ligand was developed and used for the immobilization of laccase by *** effect of pH and temperature on the enzymatic property of immobilized laccase and its catalytic capacity for pentachlorophenol（PCP） degradation were evaluated *** with free laccase,the immobilized laccase showed improved acid adaptabihty and thermal *** immobilized laccase prepared in this work exhibited a good catalytic capacity for PCP removal from aqueous solutions.

关键词： Magnetic silica Immobilization Laccase Pentachlorophenol

Effect of Solution Treatment on the Microstructure and Mechanical Properties of Sand-Cast Mg–9Gd–4Y–0.5Zr Alloy

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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 189-198页

作者： Jing-Li Li Na Zhang Xiao-Xuan Wang di Wu rong-Shi chen The Group of Magnesium Alloys and Their Applications Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China School of Materials Science and Engineering University of Science and Technology of China Hefei 230026 China AVIC Shenyang Liming Aero--Engine Group Corporation Shenyang 110043 China

Sand-cast Mg–9Gd–4Y–0.5 Zr（wt%） alloy was solution-treated at 500–565 ℃ in the time range of 0.5–30 h in air or vacuum to investigate its microstructure evolution and mechanical properties. The results showed that solution treatment temperature had a significant influence on the dissolving rate of eutectic phase and grain growth. Taken both of them into consideration, 510–520 ℃ was considered to be the optimum solution treatment temperature range for this *** should be noted that the trace（0.4–0.9 vol%） and insoluble cuboid-shaped phase precipitated during solution treatment was identified to be YH2, of which the hydrogen was thought to come from both the melting and solution heating *** addition, the 3D morphology and dissolving process of Mg24（Gd,Y）5 eutectic phases in the as-cast alloy were also discussed via in-situ observation under X-ray tomography.

关键词： Mg-Gd-Y-Zr alloy Solution treatment Microstructure Rare-earth hydride