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Positron Emission Tomography Imaging of Synaptic Dysfunction in Parkinson’s Disease

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Neuroscience Bulletin 2024年第6期40卷 743-758页

作者： Jiaqi Niu yan Zhong Chentao Jin Peili Cen Jing Wang Chunyi cui Le Xue Xingyue cui mei Tian Hong Zhang Department of Nuclear Medicine and PET Center The Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou310009China Institute of Nuclear Medicine and Molecular Imaging Zhejiang UniversityHangzhou310009China Key Laboratory of Medical Molecular Imaging of Zhejiang Province Hangzhou310009China College of Biomedical Engineering&Instrument Science Zhejiang UniversityHangzhou310014China Key Laboratory for Biomedical Engineering of Ministry of Education Zhejiang UniversityHangzhou310014China Huashan Hospital and Human Phenome Institute Fudan UniversityShanghai200040China

Parkinson’s disease(PD)is one of the most common neurodegenerative diseases with a complex *** formed by abnormal deposition of alpha-synuclein(αSyn)lead to synapse dysfunction of the dopamine and non-dopamine *** loss of dopaminergic neurons and concomitant alterations in non-dopaminergic function in PD constitute its primary pathological *** emission tomography(PET),as a representative molecular imaging technique,enables the non-invasive visualization,characterization,and quantification of biological processes at cellular and molecular *** synaptic function with PET would provide insights into the mechanisms underlying PD and facilitate the optimization of clinical *** this review,we focus on the synaptic dysfunction associated with theαSyn pathology of PD,summarize various related targets and radiopharmaceuticals,and discuss applications and perspectives of PET imaging of synaptic dysfunction in PD.

关键词： Parkinson’s disease Positron emission tomography Synapse dysfunction Alpha-synuclein Dopamine system Non-dopamine system

Well-posedness and Stability for an Elliptic-parabolic Free Boundary Problem Modeling the Growth of Multi-layer Tumors

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Acta Mathematicae Applicatae Sinica 2009年第4期25卷 547-560页

作者： Xiu-mei Hou Shang-bin cui Department of Mathematics Sun Yat-sen University Guangzhou 510275 China

In this paper we study a free boundary problem modeling the growth of multi-layer tumors. This free boundary problem contains one parabolic equation and one elliptic equation, defined on an unbounded domain in R2 of the form 0 〈 y 〈p（x,t）, where p（x,t） is an unknown function. Unlike previous works on this tumor model where unknown functions are assumed to be periodic and only elliptic equations are evolved in the model, in this paper we consider the case where unknown functions are not periodic functions and both elliptic and parabolic equations appear in the model. It turns out that this problem is more difficult to analyze rigorously. We first prove that this problem is locally well-posed in little H61der spaces. Next we investigate asymptotic behavior of the solution. By using the principle of linearized stability, we prove that if the surface tension coefficient y is larger than a threshold value y〉0, then the unique flat equilibrium is asymptotically stable provided that the constant c representing the ratio between the nutrient diffusion time and the tumor-cell doubling time is sufficiently small.

关键词： Free boundary problem multi-layer tumors well-posedness asymptotic behavior

基于人工势场法的复杂环境下多无人车避障与编队控制

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工程科学学报 2025年第2期47卷 364-373页

作者：梅艺林崔立堃胡雪岩胡广琦王浩陕西理工大学机械工程学院汉中723001

针对动态、密集障碍物等复杂环境下多车避障与编队控制存在的容易与障碍物碰撞、编队不稳定等问题,提出一种基于势场法的多车避障与编队控制方法.修改引力势场函数使引力大小在距离较大或较小时收敛于某一值,解决前期引力过大引起的无... 详细信息

针对动态、密集障碍物等复杂环境下多车避障与编队控制存在的容易与障碍物碰撞、编队不稳定等问题,提出一种基于势场法的多车避障与编队控制方法.修改引力势场函数使引力大小在距离较大或较小时收敛于某一值,解决前期引力过大引起的无人车与障碍物碰撞以及目标点不可达问题;采用更平滑的斥力计算公式对斥力势场函数进行优化,解决无人车距离障碍物过近时斥力过大引起的无人车在障碍物附近徘徊的问题;定义编队稳定力使编队前进过程中保持稳定队形的同时解决传统人工势场法存在的局部极小值问题;引入动态障碍物速度斥力势场与障碍物数量稀疏区域引力势场使编队在复杂环境下具有更高的避障与路径规划成功率.通过仿真实验与传统人工势场法以及改进后的算法进行对比,实验结果表明:本文方法在复杂环境下能够维持编队稳定性,具有较高的抗干扰能力;相较于传统算法与文献算法在动态障碍物环境下避障成功率分别提高了35%与10%,在密集动态障碍物环境下分别提高了55%与10%;能够在密集动态障碍物环境下躲避障碍物规划出合理的路径.

关键词：人工势场编队控制避障动态障碍物密集障碍物

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Non-isothermal Kinetic Analysis on the Thermal Decomposition of the Phase 517 from Hydration Product of Magnesium Sulfide Cement

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Journal of Wuhan University of Technology(Materials Science) 2023年第2期38卷 374-380页

作者： cui Baodong GUAN yan BI Wanli School of Materials and Metallurgy University of Science and TechnologyLiaoningAnshan110325China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang110159China

In order to better understand the thermodynamic properties of magnesium oxysulfate(MOS)cement,pure reagent was analyzed to prepare magnesium sulfide cement,non-isothermal kinetics calculation of the main hydration products was also carried out,and the conversion process of magnesium sulfide cement 517 phase at different temperatures was *** of magnesium sulfide cement prepared was measured by XRD technique,and decomposed by a comprehensive thermal analyzer,and DSC curves of magnesium sulfide cement under different temperature rising rates were processed by Kinssinger method and Dolye-Ozawa *** to the TG-DSC curves of magnesium sulfide cement,the thermal decomposition reaction process can be divided into five stages under normal *** DSC curve was processed by Kinssinger method and Dolye-Ozawa method,and the kinetic analysis was carried out to calculate the 517 phase activation energy of magnesium sulfide *** three stages correspond to different activation ***,flame retardant mechanism and thermal decomposition mechanism of magnesium sulfide cement based materials are deduced.

关键词： magnesium sulfide cement comprehensive thermal analysis nonisothermal dynamics 517 phase

In situ structural reconstruction of Ni Mo alloy as a versatile organic oxidation electrode for boosting hydrogen production

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Rare Metals 2022年第3期41卷 836-843页

作者： Qi Liu Meng-yang Li yan-mei Shi cui-Bo Liu Yi-Fu Yu Bin Zhang Department of Chemistry School of ScienceInstitute of Molecular PlusTianjin UniversityTianjin 300072China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Tianjin UniversityTianjin 300072China

Substitution of the electrocatalytic oxygen evolution by value-added organic synthesis is an effective and promising strategy to improve the efficiency of hydrogen evolution. Here, the Ni Mo nanorod array electrode is fabricated as the multifunctional electrode for diverse electrocatalytic organic oxidation reactions to generate carboxylic acids.

关键词： hydrogen alloy electrode

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广东韶关高岭土的矿物特性

韶关学院学报 2009年第9期30卷 61-65页

作者：龙来寿颜美凤彭翠红梁凯奚长生韶关学院化学与环境工程学院广东韶关512005

采用X射线荧光光谱分析(XRF)、化学分析、X射线衍射分析(XRD)、扫描电镜(SEM)、电子探针(EPMA)及激光粒度分析等方法,综合研究了广东韶关高岭土的化学组成、矿物组成、矿物形貌、粒度分布及铁、钛染色物质的赋存状态.结果表明:广东韶关... 详细信息

采用X射线荧光光谱分析(XRF)、化学分析、X射线衍射分析(XRD)、扫描电镜(SEM)、电子探针(EPMA)及激光粒度分析等方法,综合研究了广东韶关高岭土的化学组成、矿物组成、矿物形貌、粒度分布及铁、钛染色物质的赋存状态.结果表明:广东韶关高岭土是一种富钾高岭土,90%的颗粒粒径小于25.86μm,主要矿物为高岭石(约90%)、长石(约5%)、伊利石(约3%)、石英(约1%)、云母(约1%),此外含有少量的赤铁矿、褐铁矿、黄铁矿、锐钛矿,其中高岭石呈微鳞片层状.

关键词：高岭土矿物特性矿物组成化学成分

Endpoint Estimates for Marcinkiewicz Integrals on Weighted Weak Hardy Spaces

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Acta Mathematica Sinica,English Series 2015年第3期31卷 430-444页

作者： yan LIN mei XU School of Sciences China University of Mining and Technology

In this paper, we obtain the（W Hω^1, W Lω^1） type estimate for the Marcinkiewicz integral and the（W H1 b,ω, W L1ω） type estimate for the commutator generated by a BMO function and the Marcinkiewicz integral, w... 详细信息

关键词： μΩ boundedness kernel inequality logarithmic satisfying endpoint maximal Lebesgue proof

Temperature Rise Characteristics of Carbon-Containing Chromite Ore Fines in Microwave Field

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Journal of Iron and Steel Research International 2008年第1期15卷 1-5页

作者： LI Ning CHEN Jin yan Hong FENG Xiu-mei cui Hui-jun LIU Jin-ying College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 Shanxi China No. 12 Research Institute China Electronics Technology Group Corporation Beijing 100016 China

To avoid the nonuniform phenomena of heat and mass transfer of metallurgical powdery materials caused by conventional heating method,the temperature rise characteristics of carbon-containing chromite ore fines in the microwave field were investigated using microwave heating in a microwave metallurgical *** experimental results show that the carbon-containing chromite ore fines have better temperature rise characteristics in the microwave field at a frequency of 2.45 *** heated in the microwave field of 10 kW,the temperature of 1 kg carbon-containing chromite ore fines rose up to 1 100 ℃ in 7 min,at a temperature rise rate of 157.1（℃·min-1·kg-1）,whereas the temperature of 1 kg carbon-containing magnetite ore fines rose only up to 1 000 ℃ in 10 min,at a temperature rise rate of 100（℃·min-1·kg-1）.With increasing carbon-fitting ratios and by adding calcic lime,their heating effects changed regularly.

关键词： carbon-containing chromite ore fine carbon-containing magnetite ore fine microwave fieldl temperature rise characteristics

Numerical investigation of the failure mechanism of cubic concrete specimens in SHPB tests

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Defence Technology（防务技术） 2022年第1期18卷 1-11页

作者： mei Li Hong Hao Jian cui Yi-fei Hao Labomtory of Coast Civil Structure Safety of Ministry of Education Tianjin UniversityTiarjin300072China chool of Civil Engineering.Tianin University Tianjin300072China entre for Infrastructural Monitoring and Protection School of Civil and Mechanical Engineering Curtin UniversityPerth Western Australia6845Australia

Cylindrical specimens are commonly used in Split Hopkinson pressure bar(SHPB)tests to study the uniaxial dynamic properties of concrete-like *** recent years,true tri-axial SHPB equipment has also been developed or is under development to investigate the material dynamic properties under tri-axial impact *** such tests,cubic specimens are *** is well understood that static material strength obtained from cylinder and cube specimens are *** factors are obtained and adopted in some guidelines to convert the material streng th obtained from the two types of *** uniaxial impact tests have also demonstrated that the failure mode and the strain rate effect of cubic specimens are very different from that of cylindrical ***,the mechanical background of these findings is *** an extension of the previous laboratory study,this study performs numerical SHPB tests of cubic and cylindrical concrete specimens subjected to uniaxial impact load with the validated numerical *** stress states of cubic specimens in relation to its failure mode under different strain rates is analyzed and compared with cylindrical *** detailed analyses of the numerical simulation results show that the lateral inertial confinement of the cylindrical specimen is higher than that of the cubic specimen under the same strain *** cubic specimen,the corners aremore severely damaged because of the lower lateral confinement and the occurrence of the tensile radial stress which is not observed in cylindrical *** results explain why the dynamic material strengths obtained from the two types of specimens are different and are strain rate *** on the simulation results,an empirical formula of conversion factor as a function of strain rate is proposed,which supplements the traditional conversion factor for quasi-static material *** can be used for transforming the dynamic compressive strength from

关键词： Concrete Lateral inertial confinement Shape effet Dynamic failure mechanism Strain rate