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Journal of Environmental Sciences 2007年第11期19卷 1311-1317页

作者： zhang Zhong-chun qiu Bao-sheng College of Life Sciences Huazhong Normal University Wuhan 430079 China

Sedum alfredii Hance, a newly discovered hyperaccumulator, could serve as a good material for phytoremediation of Cd polluted sites. Malondialdehyde （MDA）, reactive oxygen species （ROS） and antioxidases （catalase （CAT）; superoxide dismutase （SOD）; peroxidase （POD）） in the leaf were determined when S. alfredii was treated for 15 d with various CdC12 concentrations ranging from 0 to 800 μmol/L. The results showed that the production rate of 2＇,7＇-dichlorofluorescein （DCF）, which is an indicator of ROS level, reached up to the maximum at 400 μmol/L CdCl2 and then declined with the increase of CdCl2 concentration, while MDA accumulation tended to increase. CAT activity was significantly inhibited at all tested CdCl2 concentrations and SOD activity was sharply suppressed at 800 μmol/L CdCl2. However, the enhancement of POD activity was observed when CdCl2 concentration was higher than 400 μmol/L. In addition, its activity increased when treated with 600 μmol/L CdCl2 for more than 5 d. When sodium benzoate, a free radical scavenger, was added, S. alfredii was a little more sensitive to Cd toxicity than that exposed to Cd alone, and the Cd accumulation tended to decline with the increase of sodium benzoate concentration. It came to the conclusions that POD played an important role during Cd hyperaccumulation, and the accumulation of ROS induced by Cd treatment might be involved in Cd hyperaccumulation.

关键词： cadmium hyperaccumulation reactive oxygen species Sedum alfredii

SIMPLE QUALITY ASSESSMENT FOR BINARY IMAGES

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Journal of Electronics(China) 2007年第2期24卷 204-208页

作者： zhang chun＇e qiu Zhengding Institute of Information Science Beijing Jiaotong University Beijing 100044 China

Usually image assessment methods could be classified into two categories: subjective as-sessments and objective ones. The latter are judged by the correlation coefficient with subjective quality measurement MOS (Mean Opinion Score). This paper presents an objective quality assessment algorithm special for binary images. In the algorithm, noise energy is measured by Euclidean distance between noises and signals and the structural effects caused by noise are described by Euler number change. The assessment on image quality is calculated quantitatively in terms of PSNR (Peak Signal to Noise Ratio). Our experiments show that the results of the algorithm are highly correlative with subjective MOS and the algorithm is more simple and computational saving than traditional objective assessment methods.

关键词： Image quality assessment Euclidean distance Euler number

模拟骨小梁假体界面微动的实验装置设计与有限元分析

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医疗卫生装备 2024年第1期45卷 25-30页

作者：石光辉张晓光李烜吕林蔚张春秋天津理工大学机械工程学院天津市先进机电系统设计与智能控制重点实验室机电工程国家级实验教学示范中心天津300384 天津市医疗器械审评查验中心天津300191

目的:设计一种模拟骨小梁假体界面微动的实验装置(以下简称“微动装置”),并进行有限元分析。方法:微动装置由带有螺纹的旋入圆筒、柔性铰、微动杆、骨小梁假体、连接杆和固定柱组成。采用SolidWorks软件构建微动装置模型,并将其导入ABA... 详细信息

目的:设计一种模拟骨小梁假体界面微动的实验装置(以下简称“微动装置”),并进行有限元分析。方法:微动装置由带有螺纹的旋入圆筒、柔性铰、微动杆、骨小梁假体、连接杆和固定柱组成。采用SolidWorks软件构建微动装置模型,并将其导入ABAQUS软件中建立有限元模型,对股骨施加轴向位移载荷,分析微动装置中柔性铰的位置、假体与股骨之间的间隙和连接杆的长度对微动的影响。结果:微动装置产生的界面微动随柔性铰距旋入圆筒下端距离的增大而增大;假体与股骨之间的间隙≥20μm时,间隙对界面微动不产生影响;界面微动随着连接杆长度的增大而增大。结论:微动装置可以准确模拟出不同的骨-骨小梁假体界面的微动,可为研究不同界面微动对骨整合的影响提供实验装置。

关键词：骨小梁假体界面微动实验装置有限元分析骨整合

全身低载高频振动参数交互作用下松质骨力学行为的模拟研究

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医疗卫生装备 2024年第7期45卷 17-23页

作者：李明志刘海英李胜刚张春秋天津理工大学天津市先进机电系统设计与智能控制重点实验室天津300384 天津理工大学机电工程国家级实验教学示范中心天津300384

目的:研究在全身低载高频振动(low-magnitude high-frequency vibration,LMHFV)参数交互作用下松质骨的力学行为,以为临床治疗废用性骨质疏松提供理论指导。方法:选取股骨中段松质骨通过Mimics软件进行三维重建,并将其导入Comsol软件中... 详细信息

目的:研究在全身低载高频振动(low-magnitude high-frequency vibration,LMHFV)参数交互作用下松质骨的力学行为,以为临床治疗废用性骨质疏松提供理论指导。方法:选取股骨中段松质骨通过Mimics软件进行三维重建,并将其导入Comsol软件中建立三维流固耦合有限元模型。设定12种振动方案(振动加速度幅值a为0.015×g、0.02×g、0.03×g,振动频率f为30、45、60、100 Hz)进行模拟研究,分析LMHFV参数交互作用下松质骨的流体力学微环境、应力及变形位移的分布规律。结果:骨小梁表面骨髓流速及其变形位移随a增加而增大,随f增加而减小。在振动方案(0.015×g/0.02×g/0.03×g,30 Hz)下,骨小梁产生的变形位移平均值较高。在LMHFV参数范围(0.02×g~0.03×g,30~35 Hz)内,骨小梁的von Mises应力值较高。结论:全身LMHFV可显著改善松质骨的受力及流体力学环境,临床上可通过合理调控LMHFV参数来提高力介导的成骨细胞生物活性,进而促进骨生成。

关键词： LMHFV 力学行为松质骨有限元模型骨质疏松

Problem identification and revitalization strategies for the recovery and reconstruction of traditional villages in the Ms 6.8 Luding Earthquake

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Journal of Mountain Science 2024年第2期21卷 361-379页

作者： HUANG Chao qiu Jian LIU chun JIANG Rui ZHAO Chuanrong zhang Yi School of Architecture and Research Center of Space Planning and Engineering Design Southwest Jiaotong UniversityChengdu 611756China Sichuan Provincial Rural Construction and Development Center Chengdu 610041China Sichuan Institute of Urban and Rural Construction Chengdu 610043China China Association for Promoting Democracy(CAPD)Sichuan Provincial Committee Chengdu 610016China Sichuan Provincial Architectural Design and Research Institute(SADI) Chengdu 610095China

Post-disaster reconstruction is a topic of global concern,and traditional villages have special heritage attributes and need to face more requirements and obstacles in post-disaster *** paper summarizes four concepts based on the research on post-disaster reconstruction both domestically and internationally,as well as the recovery and reconstruction of cultural *** a field survey of traditional villages in the Ms 6.8 Luding earthquake-stricken area,it is found that there are problems such as insufficient awareness of heritage value,misalignment of scientific reconstruction technology,and insufficient protection of reconstruction elements during the reconstruction *** villages face the risk of declining or even loss of heritage *** order to effectively protect traditional villages and inherit the carrier of regional culture,four targeted reconstruction response strategies are proposed,i.e.,to"establish special planning for traditional village preservation","emphasize recovery of the authenticity of village heritage","ensure elements for village heritage recovery"and"promote the activation and utilization of village heritage",based on the problems discovered during the survey and the four concepts summarized in the research on post-disaster reconstruction of traditional *** research results hope to provide useful reference for ancient cultural areas affected by earthquakes on how to protect cultural heritage during the post-disaster reconstruction process.

关键词： Seismic hazard Decision making Traditional village Cultural heritage protection Post-earthquake recovery and reconstruction Revitalization strategy

CRYSTAL CHEMISTRY STUDY ON PHENOLS PART 2. MOLECULAR PACING ANALYSIS　

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Chinese Chemical Letters 1996年第2期7卷 181-184页

作者： De chun zhang and Yan qiu zhang(Department of Chemistry. Suzhou University, Suzhou 215006)

Intermolecular Hydrogen Bonding (HB) Patterns in 69 crystal structures of phenols and its simple derivatives were analysed by a non-graphic method *** here are the results which are well consistent with the literature...

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The role of innate immunity in diabetic nephropathy and their therapeutic consequences

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Journal of Pharmaceutical Analysis 2024年第1期14卷 39-51页

作者： Min Yang chun zhang Department of Nephrology Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430022China

Diabetic nephropathy (DN) is an enduring condition that leads to inflammation and affects a substantial number of individuals with diabetes worldwide. A gradual reduction in glomerular filtration and emergence of proteins in the urine are typical aspects of DN, ultimately resulting in renal failure. Mounting evidence suggests that immunological and inflammatory factors are crucial for the development of DN. Therefore, the activation of innate immunity by resident renal and immune cells is critical for initiating and perpetuating inflammation. Toll-like receptors (TLRs) are an important group of receptors that identify patterns and activate immune responses and inflammation. Meanwhile, inflammatory responses in the liver, pancreatic islets, and kidneys involve inflammasomes and chemokines that generate pro-inflammatory cytokines. Moreover, the activation of the complement cascade can be triggered by glycated proteins. This review highlights recent findings elucidating how the innate immune system contributes to tissue fibrosis and organ dysfunction, ultimately leading to renal failure. This review also discusses innovative approaches that can be utilized to modulate the innate immune responses in DN for therapeutic purposes.

关键词： Innate immunity Diabetic nephropathy Inflammation Toll-like receptor Inflammasomes

Body-force modeling considering induced upstream effects for a transonic compressor with total temperature distortion

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Chinese Journal of Aeronautics 2024年第6期37卷 7-19页

作者： Jiahui qiu Chen YANG Wenqiang zhang Min zhang Juan DU Digital Twin Research Center Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China School of Engineering and Science University of Chinese Academy of SciencesBeijing 100190China National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine Chinese Academy of SciencesBeijing 100190China School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

To numerically study the impact of total temperature distortion on a transonic compressor with reduced computational costs,a Body-Force Model(BFM)is ***,the interactions between the distorted flow and the compressor are analyzed using full-annulus Unsteady Reynolds-Averaged Navier-Stokes(URANS)results and the orbit *** is found that the induced swirl distortion and the mass flux nonuniformity are intensified in the compressor upstream flow field.A correction factor is thus added to the BFM to account for the effect of the induced swirl,which is crucial for the accurate representation of distortion transfer in the ***,steady simulations with large-amplitude 180circumferential total temperature distortion are performed using the developed *** is shown that the distorted compressor map simulated with the BFM matches well with URANS *** circumferential phase shift of total temperature and the generation of the additional total pressure distortion across the rotor are in line with the time-averaged URANS flow *** compressor upstream effects on the distorted inflow can also be exactly *** above-mentioned results demonstrate the BFM developed in this paper can effectively capture the distorted flow features inside the compressor,and significantly reduce the computational costs by five orders of magnitude compared with URANS.

关键词： Upstream effect Orbit method Induced swirl distortion Body force model Correction factor Time-averaged URANS

Oligodendrocytes in central nervous system diseases:the effect of cytokine regulation

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Neural Regeneration Research 2024年第10期19卷 2132-2143页

作者： Chengfu zhang Mengsheng qiu Hui Fu Center for Cognition and Brain Disorders The Affiliated Hospital of Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Psychiatry National Clinical Research Center for Mental Disordersand National Center for Mental DisordersThe Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina Institute of Life Sciences Key Laboratory of Organ Development and Regeneration of Zhejiang ProvinceCollege of Life and Environment SciencesHangzhou Normal UniversityHangzhouZhejiang ProvinceChina Key Laboratory of Aging and Cancer Biology of Zhejiang Province School of Basic Medical SciencesHangzhou Normal UniversityHangzhouZhejiang ProvinceChina

Cytokines including tumor necrosis factor, interleukins, interferons, and chemokines are abundantly produced in various diseases. As pleiotropic factors, cytokines are involved in nearly every aspect of cellular functions such as migration, survival, proliferation, and differentiation. Oligodendrocytes are the myelin-forming cells in the central nervous system and play critical roles in the conduction of action potentials, supply of metabolic components for axons, and other functions. Emerging evidence suggests that both oligodendrocytes and oligodendrocyte precursor cells are vulnerable to cytokines released under pathological conditions. This review mainly summarizes the effects of cytokines on oligodendrocyte lineage cells in central nervous system diseases. A comprehensive understanding of the effects of cytokines on oligodendrocyte lineage cells contributes to our understanding of central nervous system diseases and offers insights into treatment strategies.

关键词： astrocyte central nervous system disease CXC chemokine cytokine interferonγ interleukin microglia oligodendrocyte oligodendrocyte precursor cell tumor necrosis factorα

Distributed Source-Load-Storage Cooperative Low-Carbon Scheduling Strategy Considering Vehicle-to-Grid Aggregators

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 440-453页

作者： Xiao Xu Ziwen qiu Teng zhang Hui Gao School of Automation Nanjing University of Posts and TelecommunicationsNanjing210023China

The vehicle-to-grid(V2G)technology enables the bidirectional power flow between electric vehicle(EV)batteries and the power grid,making EV-based mobile energy storage an appealing supplement to stationary energy storage ***,the stochastic and volatile charging behaviors pose a challenge for EV fleets to engage directly in multi-agent *** unlock the scheduling potential of EVs,this paper proposes a source-load-storage cooperative low-carbon scheduling strategy considering V2G *** uncertainty of EV charging patterns is managed through a rolling-horizon control framework,where the scheduling and control horizons are adaptively adjusted according to the availability periods of ***,a Minkowski-sum based aggregation method is employed to evaluate the scheduling potential of aggregated EV fleets within a given scheduling *** method effectively reduces the variable dimension while preserving the charging and discharging constraints of individual ***,a Nash bargaining based cooperative scheduling model involving a distribution system operator(DSO),an EV aggregator(EVA),and a load aggregator(LA)is established to maximize the social welfare and improve the low-carbon performance of the *** model is solved by the alternating direction method of multipliers(ADMM)algorithm in a distributed manner,with privacy of participants fully *** proposed strategy is proven to achieve the objective of low-carbon economic operation.

关键词： Electric vehicle(EV) low-carbon scheduling mobile storage system Nash bargaining power flexibility alternating direction method of multipliers(ADMM).