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Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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Chinese Science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, zhao Weijuan1, LI Rongwu2, XIE Jianzhong1, FENG Songlin3, fan Dongyu3, ZHANG Ying3, CAI Zhifang3, ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 450052, china 2. department of Physics, beijing normal university, beijing 100875, china 3. High Energy Physics Institute, the Chinese Academy of Sciences, beijing 100080, china 4. Archaeology Research Institute, Shanxi Province, Xian 710000, china Correspondence should be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China department of Physics Beijing Normal University Beijing 100875 China High Energy Physics Institute Chinese Academy of Sciences Beijing 100080 China Archaeology Research Institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 29 kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (1271—1368 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—1279 A.D.) and the Jin Dynasty (1115—1234 A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析

Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4DPG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2,4), fan LIAO~(2,4), Chang-qi zhao~2, Yong-da LIN~2, Ming-xue ZUO~(2,3,5) ~2 College of Life Sciences, beijing normal university, beijing 100875 china ~3 Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, china College of Life Sciences Beijing Normal University Beijing 100875 China

Aim: To define the in vitro cytotoxic activities of 4-demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4DPG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4DPG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562 cell lines）. For the K562 cell line, the antiproliferation effect of 4DPG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4DPG vs 2.23x 10（-5） mol/L for etoposide). Further, 4DPG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4DPG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4DPG. Conclusion: The cytotoxicity of 4DPG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4DPG to be a potential antitumor drug.

关键词： 4-demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

基于特征光谱参数的叶片和冠层尺度茶多酚含量估算

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光谱学与光谱分析 2024年第3期44卷 814-820页

作者：段丹丹刘仲华赵春江赵钰王凡湖南农业大学园艺学院湖南长沙410128 国家农业信息化工程技术研究中心北京100097 北京市农林科学院智能装备技术研究中心北京100097

茶多酚具有很强的生理活性和抗氧化性,是茶品质的重要属性之一。相比传统茶多酚含量的测定方法,遥感技术监测茶多酚含量具有高效、精确及实时的优势,但如何利用遥感数据监测不同时期的茶多酚含量研究较少。该研究以广东省英德市的5个茶... 详细信息

茶多酚具有很强的生理活性和抗氧化性,是茶品质的重要属性之一。相比传统茶多酚含量的测定方法,遥感技术监测茶多酚含量具有高效、精确及实时的优势,但如何利用遥感数据监测不同时期的茶多酚含量研究较少。该研究以广东省英德市的5个茶园的茶叶为研究对象,对春茶、夏茶和秋茶的叶片与冠层两个尺度的茶多酚含量及对应高光谱数据进行测定,利用标准正态变量变换(SNV)对叶片和冠层的高光谱反射率数据进行预处理;然后,分别采用连续投影算法(SPA)和竞争性自适应重加权采样算法(CARS)筛选不同生长季节叶片和冠层两个尺度茶多酚的敏感波段;最后,通过偏最小二乘法(PLS)、随机森林(RF)和多元线性回归(MLR)分别构建不同时期的茶多酚含量模型并进行验证。结果表明:(1)茶多酚的含量随着季节推移显著增加,春茶茶多酚含量(15.37%)最低,夏茶茶多酚含量次之(18.29%),秋茶茶多酚含量(秋茶20.77%)最高;(2)不同敏感波段筛选的茶多酚含量的光谱特征波段主要为2100~2200 nm附近、1300~1400 nm附近、红波-红边波段及绿波段;(3)基于春茶、夏茶和秋茶冠层光谱特征构建的茶多酚模型中CARS-PLS、SPA-MLR和CARS-PLS模型精度最高,建模集R2分别为0.56、0.45和0.52,RMSE分别为1.15、1.68和1.77;验证集R2分别为0.43、0.40和0.41,RMSE分别为1.60、1.91和1.91;基于春茶、夏茶和秋茶冠层叶片光谱特征构建的茶多酚模型中SPA-PLS、CARS-PLS和SPA-MLR模型精度最高,建模集R2分别为0.50、0.42和0.42,RMSE分别为1.25、1.70和1.66;验证集R2分别为0.43、0.36和0.38,RMSE分别为1.44、1.96和2.49。研究结果表明,基于遥感数据进行不同季节的叶片和冠层两个尺度的茶多酚含量估算是可行的,在大面积实时监测茶品质特征方面具有较大的潜力。

关键词：茶多酚高光谱偏最小二乘法随机森林多元线性回归

MICROSTRUCTURAL MORPHOLOGIES AND MECHANICALBEHAVIORS OF NICKEL-BASE SINGLE CRYSTAL SUPERALLOY CMSX-2 DURING PROLONGED TENSION

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Acta Metallurgica Sinica(English Letters) 1999年第6期12卷 0-0,0-0+0-0+0页

作者： Z.F. Peng Y Y Ren B.Z. fan J. W Qin P. Yan J. C. zhao Y Q. Wang and J.H. Sun (Wuhan university of Hydraulic and Electric Engineering, Wuhan 430072, china)(Central Iron and Steel Research Institute, beijing 100081, china)

Prolonged tension tcsts were caTried out by comblning elevated temperatures with declined stresses over thc range of 760-1050° C and 780-115MPa. The effects of temperature and applied stress on rupture life, and the relations of temperuture, applied stress and mpture life to characteristic dimensions of coherent phases (γ matrix channel width and mpcd γ precipitate thickness), and to the elongation as well as to the cross sectional area reduction of thc tested specimens were investigated. Under all testing conditions, longittLdinal coalescence of seveml adjacent armys of γ precipitates could occur to dtherent extents along the direction of the applied stress axis in addition to their normal directional coarsening. The extent of γ Longitudinal coalescence became increased and its morphology tended to be irmpular with the increase of temperuture although the applied stresses were relatively lower.

关键词： superalloy CMSX-2 prolonged tension characteristic-dimension longitudinal coalescence

Proteomic analysis of mitochondria reveals a metabolic switch from fatty acid oxidation to glycolysis in the failing heart

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Science china(Life Sciences) 2009年第11期52卷 1003-1010页

作者： WANG Jun1,2, BAI Ling1,2, LI Jing3, SUN ChaoFeng1,2, zhao Jin1, CUI ChangCong1,2, HAN Ke1,2, LIU Yu1,2, ZHUO XiaoZhen1,2, WANG TingZhong1,2, LIU Ping1,2, fan FenLing1,2, GUAN YouFei3 & MA AiQun1,2 1 department of Cardiology, First affiliated hospital of medical college of Xi’an Jiaotong university, Xi’an 710061, china 2 Ion Channel Disease Laboratory, Key Laboratory of Environment and Genes Related to Diseases of Education Ministry, Xi’an 710061, china 3 department of Physiology and Pathophysiology Key Laboratory of Molecular Cardiovascular Sciences of the Ministry of Education, Peking university Health Science Center, beijing 100083, china 1. department of Cardiology First affiliated hospital of medical college of Xi’an Jiaotong University Xi’an 710061 China 2. Ion Channel Disease Laboratory Key Laboratory of Environment and Genes Related to Diseases of Education Ministry Xi’an 710061 China 3. department of Physiology and Pathophysiology Key Laboratory of Molecular Cardiovascular Sciences of the Ministry of Education Peking University Health Science Center Beijing 100083 China

This work characterizes the mitochondrial proteomic profile in the failing heart and elucidates the molecular basis of mitochondria in heart failure. Heart failure was induced in rats by myocardial infarction, and mitochondria were isolated from hearts by differential centrifugation. Using two-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization-time of flight mass spectrometry, a system biology approach was employed to investigate differences in mitochondrial proteins between normal and failing hearts. Mass spectrometry identified 27 proteins differentially expressed that involved in energy metabolism. Among those, the up-regulated proteins included tricarboxylic acid cycle enzymes and pyruvate dehydrogenase complex subunits while the down-regulated proteins were involved in fatty acid oxidation and the OXPHOS complex. These results suggest a substantial metabolic switch from free fatty acid oxidation to glycolysis in heart failure and provide molecular evidence for alterations in the structural and functional parameters of mitochondria that may contribute to cardiac dysfunction during ischemic injury.

关键词： mitochondria heart failure proteome two-dimensional electrophoresis energy metabolism

基于光电传感的小动物主动运动行为评价及运动动机的神经机制研究

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中国体育科技 2024年第7期60卷 48-56页

作者：赵旭东薛亦飞王华林范益铭毛兰群侯莉娟北京师范大学北京100875

目的:构建小鼠主动运动行为量化评价系统,为运动与主动健康机制研究、慢病运动干预搭建平台,并通过在体实时采集主动运动不同阶段的脑电信号,探讨运动动机的神经调控机制。方法:1)构建基于光电传感的主动运动多模态系统(voluntary exerc... 详细信息

目的:构建小鼠主动运动行为量化评价系统,为运动与主动健康机制研究、慢病运动干预搭建平台,并通过在体实时采集主动运动不同阶段的脑电信号,探讨运动动机的神经调控机制。方法:1)构建基于光电传感的主动运动多模态系统(voluntary exercise multimodal system, VEMS),包括基于霍尔传感电信号的运动行为采集系统和基于机器视觉的运动轨迹分析系统;2)以C57BL/6小鼠为研究对象,应用VEMS系统记录小鼠主动运动行为并进行量化分析;3)结合在体多通道电生理记录技术采集小鼠主动运动不同阶段中脑腹侧被盖区(ventral tegmental area,VTA)神经元电活动,分析运动动机的神经编码特征。结果:1)VEMS系统可实现小鼠运动节律、运动距离、运动圈数、运动速度、运动时长和运动频次等行为数据的采集及量化分析;2)小鼠日运动时间主要集中在19:00—次日7:00,表现出较强的夜行节律,日运动距离最多可达15 km。每小时最大运动量出现在夜间1:00—2:00,运动圈数为0圈/10 min~170圈/10 min,每小时最大运动频次为23次,速度区间分布在0~12 m/min;3)在运动准备期、运动期及运动停止期,VTA神经元表现出不同的局部场单位(local field potentials,LFPs)特征信号,与运动停止期相比,运动准备期和运动期LFPs信号的θ频段(4~8 Hz)功率谱密度显著升高(P1),且振荡显著增强(P1);4)研究记录到59个对运动特异性响应的多巴胺(dopamine,DA)神经元,平均放电频率为(5.01±0.89) Hz,其中21%的DA神经元(Type-Ⅰ)在运动准备期高频放电,42%的DA神经元(Type-Ⅱ)在运动期有较强放电活动,37%(Type-Ⅲ)在运动停止后放电活动增多(P1)。结论:1)本研究首次创建了VEMS系统,该系统能够对小鼠的主动运动行为进行多维度采集与量化评价分析,不仅为后期精准运动处方制定提供参考模型,还为运动神经科学的研究提供在体实时脑信号采集平台;2)小鼠主动运动行为受到VTA神经元特异性调节,DA神经元在运动准备期、运动期、运动停止期发挥不同作用。Type-Ⅰ和Type-Ⅲ神经元分别在运动准备期和运动停止期双向正反编码,即Type-Ⅰ神经元对奖励性正面信号表现出放电增强,而Type-Ⅲ神经元在运动停止时表现出特异放电。

关键词：主动运动运动动机光电传感在体多通道电生理 VTA神经元

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气溶胶对降水影响的现象和机制

Science Bulletin 2024年第10期69卷 1569-1580页

作者：赵传峰孙悦杨杰李杰峰周月杨以坤范昊赵辛 department of Atmospheric and Oceanic Sciences School of Physicsand China Meteorological Administration Tornado Key LaboratoryPeking UniversityBeijing 100871China Institute of Carbon Neutrality Peking UniversityBeijing 100871China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China School of Environment Beijing Normal UniversityBeijing 100875China

Aerosols greatly influence precipitation characteristics,thereby impacting the regional climate and human *** an indispensable factor for cloud formation and a critical radiation budget regulator,aerosols can affect precipitation intensity,frequency,geographical distribution,area,and ***,discrepancies exist among current studies due to aerosol properties,precipitation types,the vertical location of aerosols and meteorological *** development of technology has driven advances in current research,but understanding the aerosol effects on precipitation remain complex and *** paper revolves around the following topics from the two perspectives of Aerosol-Radiation Interaction(ARI)and Aerosol-Cloud Interaction(ACI):(1)the influence of different vertical locations of absorbing/scattering aerosols on the atmospheric thermal structure;(2)the fundamental theories of ARI reducing surface wind speed,redistributing water vapour and energy,and then modulating precipitation intensity;(3)different aerosol types(absorbing versus scattering)and aerosol concentrations causing different precipitation diurnal and weekly variations;(4)microphysical processes(cloud water competition,invigoration effect,and evaporation cooling)and observational evidence of different effects of aerosols on precipitation intensity,including enhancing,inhibiting,and transitional effects from enhancement to suppression;and(5)how meteorology,water vapor and dynamics influencing the effect of ACI and ARI on *** addition,this review lists the existing issues and future research directions for attaining a more comprehensive understanding of aerosol effects on ***,this review advances our understanding of aerosol effects on precipitation and could guide the improvement of weather and climate models to predict complex aerosol-precipitation interactions more accurately.

关键词： Aerosol Precipitation Aerosol-Radiation Interaction(ARI) Aerosol-Cloud Interaction(ACI) Mechanism

Vibronic effect study of ^(1)A_(2) state of H_(2)O and D_(2)O

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Chinese Physics B 2024年第5期33卷 395-399页

作者：张倍源王礼涵朱剑辉徐卫青马子茹赵小利吴勇朱林繁 department of Modern Physics University of Science and Technology of ChinaHefei 230026China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China department of Physics Yantai UniversityYantai 264005China Institute of Applied Physics and Computational mathematics Beijing 100088China School of Physics and Information Technology Shaanxi Normal UniversityXi'an 710119China HEDPS Center for Applied Physics and TechnologyPeking UniversityBeijing 100084China

The generalized oscillator strengths of the dipole-forbidden excitations of the ^(1)A_(2) of H_(2)O and D_(2)O were calculated with the time dependent density functional theory,by taking into account the vibronic *** is found that the vibronic effect converts the dipole-forbidden excitation of the ^(1)A_(2) into a dipole-allowed one,which enhances the intensities of the corresponding generalized oscillator strength in the small squared momentum transfer *** present investigation shows that the vibronic effect of H_(2)O is slightly stronger than that of D_(2)O,which exhibits a clear isotopic effect.

关键词： water heavy water generalized oscillator strength vibronic effect isotope effect

A novel strategy for partial functional recovery of completely transected lower thoracic spinal cord of adult rats

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A novel strategy for partial functional recovery of complete...