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Analysis of G-banding in tumor cell lines derived from human neural stem cells

Neural Regeneration Research 2006年第2期1卷 115-117页

作者： junhua zou yanhui li Department of Medical Genetics Peking University HealthScience Center Beijing100083 China

BACKGROUND： The application of neural stem cell （NSC） is restricted because of its tumorigenesis, and the possible pathogenesis needs investigation. OBJEETIVE： To compare the differences of chromosomal G-banding between human NSCs （hNSCs） derived tumor cell line and hNSCs derived normal cell lines. DESIGN： A randomized controlled observation SETTING ： Building of Anatomy, Peking University Health Science Center MATERIALS ①The hNSC lines and hNSC-derived tumor cell lines were provided by the Research Center of Stem Cells, Peking University; DMEM/F12 （1：1） medium, N2 additive, B27 additive epidermal growth factor （EGF） and basic fibroblast growth factor （bFGF） were produced by GIBCO BRL Company （USA）; fetal bovine serum by HYCLONE Company （USA）. METHODS： The experiments were carried out in the Department of Genetics, Peking University Health Science Center from February 2003 to July 2004. Human fetal striatal NSCs were inoculated hypodermically on the right scapular of nude mice; Normal human fetal striatal NSCs were cultured to 5-8 passages as controls. Karyotyping was performed on the 5^th passage of hNSC-derived tumor cells at 6 weeks after hNSC transplantation into nude mice （T1） and tumor cells at 15 weeks after transplantation （T2）. Metaphase chromosomes were examined with microscope, G-banding cytogenetic analysis and karyotyping were performed according to the Cytoscan Karyotyping FISH and CGH software system （United biotechnology USA Corporation）. MAIN OUTCOME MEASURES： G-banded analytical results of human fetal striatal nerve stem cells derived tumor cell lines （T1 and T2） of metaphase chromosomes were observed. RESULTS： ① Chromosome analysis of hNSC-derived tumor cell lines 1 （T1）： Twenty-five well-spread metaphases were randomly selected for analysis. The karyotypes were 64, XX （8, 32%）; 65, XX （1, 4%）; 67, XX （5, 20%）; 68, XX （11, 44%）. The modal number of chromosomes in this cell lines was 68, which were all hypotriploid. The analysis of 8 G-ba

关键词： stem cell

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爆炸载荷作用下金属管芯夹芯板的动态响应与吸能机理研究

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振动与冲击 2024年第18期43卷 1-11页

作者：邹朋来蔡路军张威李嫣惠钟冬望武汉科技大学理学院湖北省智能爆破工程技术研究中心武汉430065 西安交通大学机械结构强度与振动国家重点实验室西安710049 江汉大学省部共建精细爆破国家重点实验室武汉430056

制备简单,价格低廉,能产生显著塑性变形的薄壁金属管芯夹芯结构在抗爆炸冲击防护领域具有广泛的应用前景。该文设计了具有面板几何非对称和芯材横向密度梯度分布的新型金属管芯夹芯板,采用数值模拟的方法对其爆炸冲击响应和能量吸收机... 详细信息

制备简单,价格低廉,能产生显著塑性变形的薄壁金属管芯夹芯结构在抗爆炸冲击防护领域具有广泛的应用前景。该文设计了具有面板几何非对称和芯材横向密度梯度分布的新型金属管芯夹芯板,采用数值模拟的方法对其爆炸冲击响应和能量吸收机理进行了研究。获得了金属管芯夹芯板的动态响应过程与特征,讨论了起爆高度,炸药质量,面板质量分布,芯材横向密度梯度分布对变形和能量吸收的影响。研究结果表明:金属管芯夹芯板的爆炸冲击响应过程可以分为三个阶段——芯层压缩、整体变形和弹性变形恢复;随着炸药质量的增加,起爆高度的降低,金属管芯夹芯板的后面板中心位移增加,芯层能量吸收占比下降;适当增加前、后面板厚度比和采用管芯密度正梯度分布的金属管芯夹芯板能更好地分散爆炸冲击波,提升芯层变形吸能效率,获得更好的抗爆效果。

关键词：管芯夹芯结构梯度非对称抗爆能力能量吸收

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基于图神经网络的变压器短路电流计算方法

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全球能源互联网 2024年第3期7卷 303-311页

作者：邹德旭洪志湖代维菊黎文浩徐衍会郑乐南方电网云南电网有限责任公司电力科学研究院云南省昆明市650217 南方电网科学研究院有限责任公司广东省广州市510700 华北电力大学电气与电子工程学院北京市海淀区100226

近年来,随着电力系统复杂程度日益提高,变压器运行安全已成为影响电力系统稳定运行的关键因素。目前流经变压器短路电流计算多基于电网拓扑结构及变压器等效阻抗等数据,此类方法的灵活性和实时性较低,未考虑系统实际运行方式,难以满足... 详细信息

近年来,随着电力系统复杂程度日益提高,变压器运行安全已成为影响电力系统稳定运行的关键因素。目前流经变压器短路电流计算多基于电网拓扑结构及变压器等效阻抗等数据,此类方法的灵活性和实时性较低,未考虑系统实际运行方式,难以满足电力系统实时运行的要求。为此,基于图卷积神经网络,提出一种考虑潮流条件下的变压器短路电流计算方法,通过引入变压器各侧母线和区域拓扑,训练得到变压器短路电流计算模型。引入注意力机制,使模型对不同运行条件下的电网潮流动态更为敏感。经过某区域实际电网算例验证,该方法计算得到的短路电流相较于参考值误差较小,且计算误差分布集中,可基本满足实际运行中对于短路电流计算的要求。

关键词：短路电流变压器图卷积神经网络注意力机制

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柑橘感染褐斑病过程中BAG1的作用

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园艺学报 2024年第5期51卷 956-970页

作者：周慧珍张嘉胡军华李白雪曹立余歆王福生邹修平周彦西南大学柑桔研究所国家柑桔工程技术研究中心重庆400712

本研究旨在探究柑橘BAG1参与褐斑病菌(Alternaria alternata)侵染的调控机制。从‘秤砣红橘’(Citrus tangerina *** Tanaka)、‘宫本温州蜜柑’(*** Macf)、‘爱媛38’杂柑(*** Blanco)和‘金秋砂糖橘’(*** Blanco)叶片中扩增BAG1基因... 详细信息

本研究旨在探究柑橘BAG1参与褐斑病菌(Alternaria alternata)侵染的调控机制。从‘秤砣红橘’(Citrus tangerina *** Tanaka)、‘宫本温州蜜柑’(*** Macf)、‘爱媛38’杂柑(*** Blanco)和‘金秋砂糖橘’(*** Blanco)叶片中扩增BAG1基因。BAG1蛋白相对保守,均具有Ubiquitin泛素结构域和BAG结构域,‘爱媛38’的BAG结构域存在3个新的氨基酸变动,导致侧链基团变动。上游启动子序列显示4个柑橘品种均包含相同的激素和胁迫相关顺式作用元件。系统分析显示4个柑橘品种与宽皮柑橘类BAG1蛋白聚为一支,相似度最高,与甜橙类、柚类亲缘关系较远。qRT-PCR显示在褐斑病菌THJ菌株侵染的抗、感品种上BAG1的表达差异显著。BAG1受外源Me JA、ABA和SA诱导上调表达。烟草亚细胞定位显示BAG1存在于细胞核和细胞膜中。BAG1沉默能够增强对***的抗性,过表达对***的抗性降低。表明BAG1通过参与活性氧激发和ABA、JA或SA信号途径,参与柑橘对褐斑病菌的调控。

关键词：柑橘 BAG1 褐斑病菌感病基因活性氧

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Formation and crystallization behavior of Fe-based amorphous precursors with pre-existingα-Fe nanoparticles-Structure and magnetic properties of high-Cu-content Fe-Si-B-Cu-Nb nanocrystalline alloys

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Journal of Materials Science & Technology 2021年第6期65卷 171-181页

作者： yanhui li Xingjie Jia Wei Zhang Yan Zhang Guoqiang Xie Zhiyong Qiu junhua Luan Zengbao Jiao Key Laboratory of Materials Modification by Laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Institute for Materials Research Tohoku UniversitySendai 980-8577Japan School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China Center for Advanced Structural Materials Department of Materials Science and EngineeringCity University of Hong KongHong KongChina Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

Structure,crystallization behavior,and magnetic properties of as-quenched and annealed Fe_(81.3)Si_(4)O_(13)Cu_(1.7)(Cu1.7)alloy ribbons and effects of Nb alloying have been ***-dimensional atom probe and transmission electron microscopy analyses reveal that high-number-density Cu-clusters and Pre-existing Nano-sized a-Fe Particles(PN-a-Fe)are coexistence in the melt-spun Cu1.7 amorphous matrix,and the PN-α-Fe form by manners of one-direction adjoining and enveloping the ***-step crystallization behavior associated with growth of the PN-a-Fe and subsequent nucleation and growth of newly-formedα-Fe is found in the primary crystallization stage of the Cu1.7 *** number densities of the Cu-clusters and PN-a-Fe in melt-spun Fe8_(1.3-x)Si_(4)B_(13)Cu_(1.7)Nb_(x)alloys are gradually reduced with enriching of Nb,and a fully amorphous structure forms at 4 at.%Nb,although smaller Cu-clusters still *** annealing,2 at.%Nb coarsens the average size(D_(α-F)e)of theα-Fe grains from 14.0 nm of the Nb-free alloy to 21.6 nm,and 4 at.%Nb refines the D_(α-Fe)to 8.9 *** mechanisms of theα-Fe nucleation and growth during quenching and annealing for the alloys with large quantities of PN-α-Fe as well as after Nb alloying have been discussed,and an annealing-induced oc-Fe growth mechanism in term of the barrier co-contributed by competitive growth among the PN-a-Fe and diffusion-suppression effect of Nb atoms has been proposed.A coercivity(HC)αDα-Fe^(3)correlation has been found for the nanocrystalline alloys,and the permeability is inverse with the H_(C).

关键词： Fe-based nanocrystalline alloy Cu-cluster Pre-existingα-Fe nanoparticle Crystallization behavior Soft magnetic property

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Different structural origins for different sized surface pits observed on a-plane GaN film

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Science China(Technological Sciences) 2016年第1期59卷 156-161页

作者： GAO ZhiYuan li JiangJiang XUE XiaoWei CUI BiFeng XING yanhui zou DeShu Microelectronic School Beijing University of Technology

A correlation study between the observed surface morphology using high-resolution scanning electron microscopy(HRSEM) and the observed structural imperfections using transmission electron microscopy(TEM) has been conducted for a-plane Ga N. There are three different sized asymmetric surface pits: large pit of 500 nm–2 ?m in side length, medium pit of 50 nm in side length, and small pit with side lengths of less than 5 nm, which originate from incomplete island coalescence, screw dislocation, and partial dislocation(PD), respectively. Both screw dislocation and PD can produce pits on the free surface because they have a perpendicular line tension to the surface, which must remain in balance with the surface tension. The two types of dislocation lead to distinctive pit sizes because the PD has a smaller Burgers vector component along the dislocation line than the pure screw dislocation. A pit that is produced in the island-coalescing process is much larger than those caused by dislocations because island coalescence is a kinetic process that involves large-scale mass transportation, whereas the dislocation mediates the surface in the local area. These three types of surface pits sometimes interact with one another in space. The coalescence of the island determines the surface morphology at large scales, whereas the defects affect the details.

关键词： surface pits nonpolar Ga N screw dislocations partial dislocations Island coalescence

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Understanding the structural evolution of Au/WO_(2.7) compounds in hydrogen atmosphere by atomic scale in situ environmental TEM

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Nano Research 2020年第11期13卷 3019-3024页

作者： Fei Hui Chong li yanhui Chen Chunhui Wang Jingping Huang Ang li Wei li Jin zou Xiaodong Han Key Lab of Microstructure and Property of Advanced Materials Beijing University of TechnologyBeijing100124China International Laboratory for Quantum Functional Materials of Henan School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou450001China School of Mechanical and Mining Engineering and Centre for Microscopy and Microanalysis The University of QueenslandSt LuciaQLD4072Australia

Hydrogen energy is a resuscitated clean energy source and its sensitive detection in air is crucial due to its very low explosive *** oxide decorated with noble metal nanoparticles has been used for the enhancement of gas detection and exhibits superior *** the intrinsic mechanism of the detection and the enhancement mechanism is thus becoming a fundamental issue for the further development of novel metal/oxide compound gas-sensing ***,the correlation between the microstructural evolution,the charge transport and the complex sensing process has not yet been directly revealed and its atomic mechanism is still *** this study,an Au/WO_(2.7) compound was synthesized and exhibited a strongly enhanced gas sensitivity to many reductive gases,especially ***-corrected environmental transmission electron microscopy was used to investigate the atomic-scale microstructural evolution in situ during the reaction between H_(2) and Au/WO_(2.7) *** and sintering processes of the Au particles on the WO_(2.7) surface were observed under heating and gaseous environments,and no injection of hydrogen atoms was *** principle calculations verified the swing and sintering processes,and they can be explained by the enhancement of H2 sensitivity.

关键词： in situ environmental TEM H2 sensing Au/WO_(2.7) gas-solid interface

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miR-1290对非酒精性脂肪性肝病的调控机制研究

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同济大学学报（医学版） 2024年第4期45卷 488-495页

作者：邹琳孙菲李映璇陈霞马俊花上海市浦东新区公利医院内分泌科上海200135

目的探讨miRNAs是否参与非酒精性脂肪性肝病(non-alcoholic fatty liver disease,NAFLD)的发病过程以及miR-1290对NAFLD GH/IGF1轴调控的可能机制。方法通过GenBank GEO数据库,Targetscan、mirBase、miRanda等miRNA生物数据库以及大量文献阅读筛选出在NAFLD中异常表达的miRNAs,再通过GO和KEGG分析靶基因预测软件筛选出与GH/IGF1轴基因相关的miRNAs;利用1 nmol/L游离脂肪酸(free fatty acid,FFA)诱导人肝细胞HL-7702(L02)并建立NAFLD的细胞模型(L02 NAFLD);通过不同浓度的rhGH、rhIGF1干预L02细胞及NAFLD细胞;观察不同浓度干预后相关miRNAs的基因表达变化;使用细胞转染技术进行验证。结果与L02细胞相比,L02 NAFLD细胞中miR-16、miR-1290、miR-122的表达上调(P0.05)。结论miRNAs在NAFLD中表达异常,miR-1290在NAFLD中表达上调,miR-1290可能通过GH/IGF1参与NAFLD脂质代谢及胰岛素抵抗发病过程。

关键词：非酒精性脂肪性肝病 miRNAs 胰岛素抵抗脂代谢 GH/IGF1轴

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高压断路器操动机构非侵入式多信息检测及故障诊断研究

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高压电器 2024年第7期60卷 128-137页

作者：李建鹏赵冀宁孟延辉赵智龙赵书涛邹园刘晓飞国网河北省电力有限公司超高压分公司石家庄050070 华北电力大学河北保定071003 国网河北省电力有限公司培训中心石家庄050031

高压断路器的操动机构是保障断路器可靠动作的关键部件,准确判断操动机构状态至关重要。提出了基于图像、振动、声音的非侵入式多信息检测方法,对提取的图像特征向量(分闸时间、合闸时间、分闸速度、合闸速度、分闸行程、合闸行程)、振... 详细信息

高压断路器的操动机构是保障断路器可靠动作的关键部件,准确判断操动机构状态至关重要。提出了基于图像、振动、声音的非侵入式多信息检测方法,对提取的图像特征向量(分闸时间、合闸时间、分闸速度、合闸速度、分闸行程、合闸行程)、振动特征向量(特征时间点、等能量5分段能量熵)、声音特征向量(特征时间点、等能量5分段能量熵)和操动机构状态(正常、基座松动、转轴卡涩、缓冲器性能下降、拐臂润滑不足)进行了多重对应分析,找到了机构状态和相应特征向量的关联关系。提出了基于机构状态和相应特征向量关联关系的分级诊断策略,经实验室故障模拟及诊断,基座松动故障、转轴卡涩故障、缓冲器性能下降故障的联合特征诊断较单一信号诊断正确率分别提升至90%、80%、90%,拐臂润滑不足故障的联合特征诊断准确率较单一信号诊断没有明显的提高。经现场实测及设备解体分析,证明了方法的通用有效性。

关键词：操动机构图像振动声音多重对应分析分级诊断

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RESEARCH ON INDOOR ELECTROMAGNETIC RADIATION FIELD OF MULTIPLE ANTENNA SYSTEM

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Journal of Electronics(China) 2012年第5期29卷 400-407页

作者： Ma li Lu yanhui zou Peng Zhou Xiaoping Institute of Information Engineering Zhengzhou University

The complexity of the indoor environment brings great challenges to predict the electromagnetic radiation field of multiple antenna systems. Based on the Finite Difference Time Domain (FDTD) algorithm, using the mobile phone shielding device as the multiple antenna systems example, the mobile phone shielding device's indoor electromagnetic radiation field is researched by measurment method and simulation method. The effectivity of prediction method is verified by comparing the prediciton results with the measurment results. About 80% of the error can be controlled less than dB. The quantitative research has certain guiding significance to the prediction of the multiple antenna systems radio wave propagation.

关键词： Electromagnetic radiation field Multiple antenna systems Field intensity prediction Finite Difference Time Domain (FDTD) Indoor environment

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