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Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

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Neural Regeneration Research 2025年第11期20卷 3245-3258页

作者： Jiayi Wang Mengke Zhao Dong Fu Meina Wang chao han Zhongyue Lv Liang Wang Jing Liu Stem Cell Clinical Research Center The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina Institute(College)of Integrative Medicine Dalian Medical UniversityDalianLiaoning ProvinceChina

Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived *** lays a foundation for the development of potentially potent new treatment modalities for ischemic ***,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical *** promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic *** found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal *** human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase B,and these effects were reversed by treatment with a phosphoinositide 3-kinase *** findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling ***,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety ***,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

关键词： behavior exosome extracellular vesicles ischemic stroke mammalian target of rapamycin(mTOR) middle cerebral artery occlusion neural stem cells neuronal apoptosis phosphoinositide 3-kinase(PI3K) protein kinase B(AKT)

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Three-Dimensional Scene Encryption Algorithm Based on Phase Iteration Algorithm of the Angular-Spectral Domain

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1074-1080页

作者： chao han Yuzhen Shen the School of Electrical Engineering Anhui Polytechnic Universityand also with the Key Laboratory of Advanced Perception and Intelligent Control of High-end EquipmentMinistry of EducationWuhu 241000China

In order to increase the capacity of encrypted information and reduce the loss of information transmission, a three-dimensional(3 D) scene encryption algorithm based on the phase iteration of the angular spectrum domain is proposed in this paper. The algorithm, which adopts the layer-oriented method, generates the computer generated hologram by encoding the three-dimensional scene. Then the computer generated hologram is encoded into three pure phase functions by adopting the phase iterative algorithm based on angular spectrum domain,and the encryption process is completed. The three-dimensional scene encryption can improve the capacity of the information,and the three-phase iterative algorithm can guarantee the security of the encryption information. The numerical simulation results show that the algorithm proposed in this paper realized the encryption and decryption of three-dimensional scenes. At the same time, it can ensure the safety of the encrypted information and increase the capacity of the encrypted information.

关键词： Angular spectrum diffraction information capacity phase iteration three-dimensional scene encryption

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Elliptical formation control based on relative orbit elements

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Chinese Journal of Aeronautics 2013年第6期26卷 1554-1567页

作者： Yin Jianfeng han chao School of Astronautics Beihang University

A new set of relative orbit elements（ROEs）is used to derive a new elliptical formation flying ***-plane and out-of-plane motions can be completely decoupled,which benefts elliptical formation *** inverse transformation of the state transition matrix is derived to study the relative orbit control *** feedback control laws are developed for both in-plane and out-of-plane relative *** of in-plane and out-of-plane relative motions can be completely decoupled using the ROE-based feedback control law.A tangential impulsive control method is proposed to study the relationship of fuel consumption and maneuvering *** optimal analytical along-track impulsive control strategy is then *** typical orbit maneuvers,including formation establishment,reconfguration,long-distance maneuvers,and formation keeping,are taken as examples to demonstrate the performance of the proposed control *** effects of relative measurement errors are also considered to validate the high accuracy of the proposed control method.

关键词： Elliptical formation control Formation flying Fuel optimal Impulsive control Relative orbit elements

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Rapid satellite-to-site visibility determination based on self-adaptive interpolation technique

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Science China(Technological Sciences) 2017年第2期60卷 264-270页

作者： han chao GAO XiaoJie SUN XiuCong School of Astronautics Beihang University Beijing 100191 China

Rapid satellite-to-site visibility determination is of great significance to coverage analysis of satellite constellations as well as onboard mission planning of autonomous spacecraft. This paper presents a novel self-adaptive Hermite interpolation technique for rapid satellite-to-site visibility determination. Piecewise cubic curves are utilized to approximate the waveform of the visibility function versus time. The fourth-order derivative is used to control the approximation error and to optimize the time step for interpolation. The rise and set times are analytically obtained from the roots of cubic polynomials. To further increase the computational speed, an interval shrinking strategy is adopted via investigating the geometric relationship between the ground viewing cone and the orbit trajectory. Simulation results show a 98% decrease in computation time over the brute force method. The method is suitable for all orbital types and analytical orbit propagators.

关键词： satellite-to-site visibility rapid determination self-adaptive Hermite interpolation viewing cone

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A Backstepping Simple Adaptive Control Application to Flexible Space Structures

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Chinese Journal of Aeronautics 2012年第3期25卷 446-452页

作者： LIU Min XU Shijie han chao School of Astronautics Beihang UniversityBeijing 100191China

Although the simple adaptive control （SAC） is widely studied both in theory and application in flexible space structure control and other control problems, it is restricted by the almost strictly positive real （ASPR） conditions. In most practical control problems, the ASPR conditions are not satisfied. Therefore, based on the SAC theory, this paper proposes a backstepping simple adaptive control algorithm which suits the system with arbitrary relative degree with no need of parallel feed forward compensa- tor. The proposed control algorithm consists of decomposition of the arbitrary relative degree system into a known subsystem and an unknown ASPR subsystem which are connected in cascade, design of constant output feedback controller for the known subsystem, and implementation of backstepping method and SAC of the unknown ASPR subsystem. Inheriting the characteristics of the SAC, this method can be adaptive online for the parameter uncertainties. Then, the application of the proposed controller to large flexible space structure with collocated sensors and actuators is studied, and the simulation results validate the proposed controller. It is a new strategy to apply the classical SAC to high relative degree plants.

关键词： simple adaptive control almost strictly positive real backstepping flexible structure intermediate control law

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An efficient technique for recovering responses of parameterized structural dynamic problems

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Acta Mechanica Sinica 2011年第5期27卷 757-766页

作者： Zheng Zhang Xu han chao Jiang State Key Laboratory of Advanced Designand Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan University 410082 Changsha China

In this article,an effective technique is developed to efficiently obtain the output responses of parameterized structural dynamic *** technique is based on the conception of reduced basis method and the usage of linear interpolation *** original problem is projected onto the reduced basis space by linear interpolation projection,and subsequently an associated interpolation matrix is *** ensure the largest nonsingularity,the interpolation matrix needs to go through a timenode choosing process,which is developed by applying the angle of vector *** a part of this technique,error estimation is recommended for achieving the computational error *** ensure the successful performance of this technique,the offline-online computational procedures are conducted in practical *** numerical examples demonstrate the accuracy and efficiency of the presented method.

关键词： Reduced basis method · Structural dynamic response · Real-time computation · Linear interpolation · Fast Fourier transform

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Evaluation and prediction of slope stability using machine learning approaches

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Frontiers of Structural and Civil Engineering 2021年第4期15卷 821-833页

作者： Shan LIN Hong ZHENG chao han Bei han Wei LI Key Laboratory of Urban Security and Disaster Engineering Ministry of EducationBeijing University of TechnologyBeijing100124China

In this paper,the machine learning(ML)model is built for slope stability evaluation and meets the high precision and rapidity requirements in slope *** ML methods for the factor of safety(FOS)prediction are studied and compared hoping to make the best use of the large variety of existing statistical and ML regression methods *** data set of this study includes six characteristics,namely unit weight,cohesion,internal friction angle,slope angle,slope height,and pore water pressure *** whole ML model is primarily divided into data preprocessing,outlier processing,and model *** the data preprocessing,the duplicated data are first removed,then the outliers are filtered by the LocalOutlierFactor method and finally,the data are standardized.11 ML methods are evaluated for their ability to learn the FOS based on different input parameter *** analyzing the evaluation indicators R2,MAE,and MSE of these methods,SVM,GBR,and Bagging are considered to be the best regression *** performance and reliability of the nonlinear regression method are slightly better than that of the linear regression ***,the SVM-poly method is used to analyze the susceptibility of slope parameters.

关键词： slope stability factor of safety regression machine learning repeated cross-validation

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近70年黄河潼关站以下河段冲淤特征分析

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水土保持研究 2025年第1期32卷 48-56页

作者：韩超王飞戈文艳陈昊史尚渝刘元昊西北农林科技大学水土保持科学与工程学院中国科学院水利部水土保持研究所

[目的]揭示黄河潼关以下河段冲淤变化过程及分布特征，为未来黄河下游水土保持和调水调沙工作提供参考。[方法]对1952—2022年来潼关—花园口段、下游游荡型河段、过渡型河段、弯曲型河段输沙特征和冲淤过程进行分析，采用趋势分析、突... 详细信息

[目的]揭示黄河潼关以下河段冲淤变化过程及分布特征，为未来黄河下游水土保持和调水调沙工作提供参考。[方法]对1952—2022年来潼关—花园口段、下游游荡型河段、过渡型河段、弯曲型河段输沙特征和冲淤过程进行分析，采用趋势分析、突变检验与回归分析等方法，确定了不同河段的输沙、冲淤变化特征及其相互影响。[结果]潼关以下河段年输沙量在显著减少(p<0.01),1996年后各站输沙量大幅降低，近20年来沙系数均低于0.01,表现冲刷特征。各河段年淤积量呈下降趋势，潼关—花园口段和弯曲型河段仍在持续淤积，花园口—艾山段近20年淤积量则为负值。研究时段内，潼关以下河段累计淤积泥沙186.84亿t,潼关—花园口段、游荡型河段、过渡型河段和弯曲型河段分别淤积了86.75亿t, 49.45亿t, 17.14亿t, 33.49亿t。另外，输沙量和来沙系数变化分别对潼关—花园口、游荡型河段和花园口以下河段淤积影响明显(p<0.01)。[结论]小浪底水利枢纽运行及调水调沙实施后，潼关以下河段年淤积量大幅减少，潼关—花园口和弯曲型河段承载了更多泥沙，花园口—艾山段则已由淤转冲。

关键词：水沙变化黄河下游冲淤过程淤积现状

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Boron leaching:Creating vacancy-rich Ni for enhanced hydrogen evolution

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Nano Research 2022年第3期15卷 1868-1873页

作者： chao han Weijie Li Jiazhao Wang Zhenguo Huang School of Civil and Environmental Engineering Faculty of Engineering and Information TechnologyUniversity of Technology SydneyNSW 2007Australia Institute for Superconducting&Electronic Materials AIIM BuildingInnovation CampusUniversity of WollongongSquires WayNorth WollongongNSW 2500Australia Centre for Green Technology Faculty of Engineering and Information TechnologyUniversity of Technology SydneyNSW 2007Australia

Creating vacancy is often highly effective in enhancing the hydrogen evolution performance of transition metal-based ***-rich Ni nanosheets have been fabricated via topochemical formation of two-dimentional(2D)Ni_(2)B on graphene precursor followed by boron *** on graphene,a few atomic layered Ni_(2)B nanosheets are first obtained by reduction and *** number of atomic vacancies are then generated in the Ni_(2)B layer via leaching boron *** used for hydrogen evolution reaction(HER),the vacancy-rich Ni/Ni(OH)_(2 )heterostructure nanosheets demonstrate remarkable performance with a low overpotential of 159 mV at a current density of 10 mA·cm^(−2) in alkaline solution,a dramatic improvement over 262 mV of its *** enhancement is associated with the formation of vacancies which introduce more active sites for HER along Ni/Ni(OH)_(2) *** work offers a facile and universal route to introduce vacancies and improve catalytic activity.

关键词： two-dimensional structure Ni_(2)B boron leaching vacancies hydrogen evolution reaction(HER)

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Gene Expression Profile Changes in Germinating Rice

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Journal of Integrative Plant Biology 2011年第10期53卷 835-844页

作者： Dongli He chao han Pingfang Yang Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Water absorption is a prerequisite for seed germination. During imbibition, water influx causes the resumption of many physiological and metabolic processes in growing seed. In order to obtain more complete knowledge about the mechanism of seed germination, two-dimensional gel electrophoresis was applied to investigate the protein profile changes of rice seed during the first 48 h of imbibition. Thirty- nine differentially expressed proteins were identified, including 19 down-regulated and 20 up-regulated proteins. Storage proteins and some seed development- and desiccation-associated proteins were down regulated. The changed patterns of these proteins indicated extensive mobilization of seed reserves. By contrast, catabolism-associated proteins were up regulated upon imbibition. Semi-quantitative real time polymerase chain reaction analysis showed that most of the genes encoding the down- or up- regulated proteins were also down or up regulated at mRNA level. The expression of these genes was largely consistent at mRNA and protein levels. In providing additional information concerning gene regulation in early plant life, this study will facilitate understanding of the molecular mechanisms of seed germination.

关键词： rice seed two-dimensional gel electrophoresis matrix assisted baser desorption ionization-time of flight semi-quantitative real timepolymerase chain reaction germination proteomics imbibition.

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