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Chemical constituents from agarwood of Aquilaria filaria

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Journal of Chinese Pharmaceutical Sciences 2021年第6期30卷 505-517页

作者： Chengneng Mi Wenli Mei jingzhe yuan Wenxing Long HaofU Dai Hainan Engineering Research Center of Agarwood Institute of Tropical Bioscience and BiotechnologyChinese Academy of Tropical Agricultural SciencesHaikou 571101China Hainan Key Laboratory for Research and Development of Natural Products from Li Folk Medicine Haikou 571101China Institute of Tropical Agriculture and Forestry Hainan UniversityHaikou 570228China

Investigations on the chemical constituents from the ethanol extract of the agarwood originating from Aquilaria filaria led to the isolation of 26 compounds by column chromatography,including silica gel,Sephadex LH-20,and semi-preparative high-performance liquid *** structures were determined to beβ-sitostenone(1),24α-ethyl-cholestan-3α-ol(2),ergosta-4,6,8(14),22-tetraene-3-one(3),gypsogenin(4),hederagenin(5),17αH-trisnorhopanone(6),lupeol(7),friedelin(8),(-)-episyringaresinol(9),(-)-syringaresinol(10),5-hydroxy-7,4′-dimethoxyflavone(11),5,4’-dihydroxy-7,3′-dimethoxyflavone(12),2′-hydroxy-4,3′,6′,4′′-tetramethoxy-p-terphenyl(13),scopularide A(14),4-(4-hydroxyphenyl)butan-2-one(15),zingerone(16),coniferaldehyde(17),scopoletin(18),acetovanillon(19),isovanillin(20),vanillin(21),p-hydroxybenzaldehyde(22),p-hydroxybenzoic acid(23),protocatechuic acid(24),vanillic acid(25)and 4,5-dihydroxy-3-methoxybenzoic acid(26)by using spectroscopic *** compounds were isolated from agarwood of *** for the first time,and this was also the first report about the isolation of compounds 2,4,6,7,9,10,13-15,17-20,22,24 and 26 from agarwood and Aquilaria plants.

关键词： Agarwood of Aquilaria filaria Chemical constituents Triterpene Steroid

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二臂超支化聚羧酸减水剂的合成表征及性能

高分子材料科学与工程 2022年第2期38卷 46-55页

作者：姚方袁靖喆孙妍潘莉莎徐鼐庞素娟海南大学化学工程与技术学院海南海口570228

以氯化亚砜和甲氧基聚乙二醇(MPEG)为原料合成氯代甲氧基聚乙二醇(Cl-MPEG),对乙醇胺表面的氨基进行聚乙二醇(PEG)长链接枝,通过丙烯酰氯进一步引入双键合成二臂超支化聚氧乙烯醚大单体(TAHBPE)。将TAHBPE与丙烯酸小单体采用水溶液自由... 详细信息

以氯化亚砜和甲氧基聚乙二醇(MPEG)为原料合成氯代甲氧基聚乙二醇(Cl-MPEG),对乙醇胺表面的氨基进行聚乙二醇(PEG)长链接枝,通过丙烯酰氯进一步引入双键合成二臂超支化聚氧乙烯醚大单体(TAHBPE)。将TAHBPE与丙烯酸小单体采用水溶液自由基共聚法合成二臂侧链超支化型聚羧酸减水剂(TAHB-PCEs)。采用红外光谱、核磁共振、质谱、凝胶渗透色谱对合成过程的中间和最终产物进行了结构表征。结果表明,成功合成了Cl-MPEG,TAHBPE和TAHB-PCEs。净浆流动度和流变性测试结果表明,TAHB-PCEs的净浆流动度达到298.5 mm,屈服应力和黏度均小于传统梳型聚羧酸减水剂。通过表面张力、接触角对TAHB-PCEs的分散作用机理进行了探讨,保持聚羧酸减水剂的羧酸根密度不变、缩短侧链长度、增大侧链密度可降低其表面张力和表面能,有利于其在水泥表面的润湿,达到更好的减水分散性能。

关键词：聚羧酸减水剂二臂侧链超支化

The dopaminergic system and Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2495-2512页

作者： Yuhan Zhang yuan Liang Yixue Gu International Medical College Chongqing Medical UniversityChongqingChina College of Pharmacy Chongqing Medical UniversityChongqingChina Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqing Key Laboratory of NeurologyChongqingChina

Alzheimer's disease is a common neurodegenerative disorder in older *** its prevalence,its pathogenesis remains unclea *** addition to the most widely accepted causes,which in clude excessive amyloid-beta aggregation,tau hyperphosphorylation,and deficiency of the neurotransmitter acetylcholine,numerous studies have shown that the dopaminergic system is also closely associated with the occurrence and development of this *** is a crucial catecholaminergic neurotransmitter in the human ***-associated treatments,such as drugs that target dopamine receptor D and dopamine analogs,can improve cognitive function and alleviate psychiatric symptoms as well as ameliorate other clinical *** r,therapeutics targeting the dopaminergic system are associated with various adverse reactions,such as addiction and exacerbation of cognitive *** review summarizes the role of the dopaminergic system in the pathology of Alzheimer's disease,focusing on currently available dopamine-based therapies for this disorder and the common side effects associated with dopamine-related *** aim of this review is to provide insights into the potential connections between the dopaminergic system and Alzheimer's disease,thus helping to clarify the mechanisms underlying the condition and exploring more effective therapeutic options.

关键词： adverse drug reaction Alzheimer's disease catecholamine dopamine receptor dopamine receptor heterodimers dopaminergic system neurodegenerative disease neurotransmitter signaling pathways traditional Chinese medicine treatment

红树林来源真菌Xylaria ***-2异香豆素类次生代谢产物及其生物活性的研究

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热带作物学报 2019年第8期40卷 1611-1617页

作者：权云帆王佩王昊袁靖喆戴好富梅文莉海南大学热带农林学院海南海口570228 中国热带农业科学院热带生物技术研究所/海南省黎药资源天然产物研究与利用重点实验室海南海口571101 海南医学院热带医学与检验医学院海南海口571199

为了研究红树林来源真菌***-2的次生代谢产物及其生物活性,综合利用多种色谱技术对该菌株发酵产物进行分离纯化,结合波谱学与理化常数分析进行化合物结构鉴定,分别采用液体浸泡法和Ellman比色法对化合物的全齿复活线虫致死活性和乙酰胆... 详细信息

为了研究红树林来源真菌***-2的次生代谢产物及其生物活性,综合利用多种色谱技术对该菌株发酵产物进行分离纯化,结合波谱学与理化常数分析进行化合物结构鉴定,分别采用液体浸泡法和Ellman比色法对化合物的全齿复活线虫致死活性和乙酰胆碱酯酶抑制活性进行测试。从***-2发酵产物乙酸乙酯萃取物中分离鉴定了7个异香豆素类化合物,分别为(S)-(+)-8-O-methylmellein(1),(3S,4S)-(+)-4-hydroxy-8-O-methylmellein (2),(3S,4R)-(+)-4-hydroxy-8-O-methylmellein (3),(3S,4S)-(+)-4-hydroxymellein (4),(3S,4R)-(+)-4-hydroxymellein (5),(3R,4R)-(-)-4-hydroxy-5-methylmellein (6)和(3R,4S)-(+)-4-hydroxy-5-methylmellein (7)。其中,化合物1具有较强全齿复活线虫致死活性,化合物1~3、6和7具有一定的乙酰胆碱酯酶抑制活性。本研究首次发现化合物(S)-(+)-8-O--methylmellein具有较强的抗线虫活性,为相关杀线虫药物的研发提供理论依据。

关键词：红树林真菌次生代谢产物异香豆素生物活性

Toward Analytical Homogenized Relaxation Modulus for Fibrous Composite Material with Reduced Order Homogenization Method

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Computers, Materials & Continua 2025年第1期82卷 193-222页

作者： Huilin Jia Shanqiao Huang Zifeng yuan HEDPS Center for Applied Physics and Technology(CAPT)Department of Mechanics and Engineering SciencePeking UniversityBeijing100871China State Key Laboratory for Turbulence and Complex Systems Peking UniversityBeijing100871China

In this manuscript,we propose an analytical equivalent linear viscoelastic constitutive model for fiber-reinforced composites,bypassing general computational *** method is based on the reduced-order homogenization(ROH)*** ROH method typically involves solving multiple finite element problems under periodic conditions to evaluate elastic strain and eigenstrain influence functions in an‘off-line’stage,which offers substantial cost savings compared to direct computational homogenization *** to the unique structure of the fibrous unit cell,“off-line”stage calculation can be eliminated by influence functions obtained *** the standard solid model to the ROH method enables the creation of a comprehensive analytical homogeneous viscoelastic constitutive *** method treats fibrous composite materials as homogeneous,anisotropic viscoelastic materials,significantly reducing computational time due to its analytical *** approach also enables precise determination of a homogenized anisotropic relaxation modulus and accurate capture of various viscoelastic responses under different loading *** sets of numerical examples,including unit cell tests,three-point beam bending tests,and torsion tests,are given to demonstrate the predictive performance of the homogenized viscoelastic ***,the model is validated against experimental measurements,confirming its accuracy and reliability.

关键词： Homogenized relaxation modulus viscoelastic standard solid model reduced order homogenization fibrous composite material

Optimal Scheduling of an Independent Electro-Hydrogen System with Hybrid Energy Storage Using a Multi-Objective Standardization Fusion Method

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Energy Engineering 2025年第1期122卷 63-84页

作者： SuliangMa ZeqingMeng Mingxuan Chen yuan Jiang School of Electrical and Control Engineering North China University of TechnologyBeijing100144China ChinaThree Gorges Technology Co. Ltd.Beijing100032China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China

In the independent electro-hydrogen system(IEHS)with hybrid energy storage(HESS),achieving optimal scheduling is ***,it presents a challenge due to the significant deviations in values ofmultiple optimization objective functions caused by their physical *** deviations seriously affect the scheduling process.A novel standardization fusion method has been established to address this issue by analyzing the variation process of each objective function’s *** optimal scheduling results of IEHS with HESS indicate that the economy and overall energy loss can be improved 2–3 times under different optimization *** proposed method better balances all optimization objective functions and reduces the impact of their *** the cost of BESS decreases by approximately 30%,its participation deepens by about 1 ***,if the price of the electrolyzer is less than 15￥/kWh or if the cost of the fuel cell drops below 4￥/kWh,their participation will increase *** study aims to provide a more reasonable approach to solving multi-objective optimization problems.

关键词： Electro-hydrogen system multi-objective optimization standardization method hybrid energy storage system

Sex differences in aging and injured brain

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Neural Regeneration Research 2025年第10期20卷 2901-2902页

作者： Jordan N.Williamson yuan Yang University of Illinois Urbana-Champaign Grainger College of EngineeringDepartment of BioengineeringUrbanaILUSA Carle Foundation Hospital Stephenson Family Clinical Research InstituteClinical Imaging Research CenterUrbanaILUSA University of Illinois Urbana-Champaign Beckman Institute for Advanced Science and TechnologyUrbanaILUSA Northwestern University Department of Physical Therapy and Human Movement SciencesChicagoILUSA

Background:The prevalence,age of onset,and symptomatology of traumatic brain injury,stroke,and neurodegenerative diseases(such as Alzheimer’s disease(AD),Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease)differ substantially between males and *** higher prevalence of these brain disorders has been attributed to females having a greater longevity compared with *** one of the greatest risk factors of acquired brain injury(such as stroke,traumatic brain injury caused by fall)and neurodegenerative disease is age.

关键词： Huntington prevalence traumatic

Decision making module based on stochastic magnetic tunnel junctions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 202-209页

作者： Yifan Miao Li Zhao Yajun Zhang Zhe yuan Center for Advanced Quantum Studies and Department of Physics Beijing Normal University Institute for Nanoelectric Devices and Quantum Computing Fudan University Interdisciplinary Center for Theoretical Physics and Information Sciences Fudan University

In biological neural systems, noise is ubiquitous but does not affect the correct decisions made in the complex cognitive ***-making in biological neural system is typically achieved by accumulating input information over a period of *** by recent developments in neurosciences, we design a decision-making module based on spintronic devices, utilizing superparamagnetic tunnel junctions as artificial neurons. The feasibility of this decision-making module is verified through circuit simulations. Taking a multi-layer perceptron as an example, the module significantly improves the accuracy of the perceptron in the handwritten digit recognition task. Furthermore, the spintronic decision-making module offers advantages over the conventional pooling methods, such as adaptive decision time, high performance and the absence of analog-to-digital conversion. The decision-making module is flexible to be integrated into artificial neural networks and provides a general yet effective solution to enhance performance against device noise.

关键词： neuromorphic computing spintronics magnetic tunnel junction neural networks

Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期34卷 223-241页

作者： WEI Xinyi ZHANG Nan ZHANG Zhaoli CAO Xiaoling yuan Yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

关键词： copper metal foam heat transfer enhancement phase change materials regionalized enhancement