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Design and analysis of the Macao Science Satellite-1's laser retro-reflector array 被引量:1
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作者 ZhiEn Cheng Kai Tang +3 位作者 ZhongPing Zhang HaiFeng Zhang Pu Li MingLiang Long 《Earth and Planetary Physics》 EI CSCD 2023年第1期131-135,共5页
The origin and spatial-temporal variation of the Earth’s magnetic field(EMF)is one of the important scientific problems that has long been unsolved.The Macao Science Satellite-1(MSS-1)under construction is China’s f... The origin and spatial-temporal variation of the Earth’s magnetic field(EMF)is one of the important scientific problems that has long been unsolved.The Macao Science Satellite-1(MSS-1)under construction is China’s first high-precision EMF measurement satellite.To satisfy the highly precise requirements of the MSS-1 orbit measurement,a light,high-precision,four-prism laser retroreflector array was designed.It weighs approximately 285 g,its effective reflection area is greater than 1.77 cm^(2),and its size is 100×100×41 mm.The laser retro-reflector array has excellent performance,and it can achieve a ranging precision at the subcentimeter level for satellite laser ranging.It will be developed and installed on the MSS-1 as a power-free load for high-precision orbit measurement and accurate orbit calibration.The MSS-1 is planned to be brought into the International Laser Ranging Service observations.More than 31satellite laser ranging stations in the International Laser Ranging Service around the world will be able to measure the MSS-1 with long arcs,which will support the scientific mission of high-precision EMF exploration. 展开更多
关键词 Macao Science Satellite-1 Earth’s magnetic field satellite laser ranging laser retro-reflector array high-precision orbit
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TCERG1L hypermethylation is a risk factor of diabetic retinopathy in Chinese children with type 1 diabetes
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作者 Yu Qian Ying Xiao +8 位作者 Qiu-Rong Lin Zhao-Yu Xiang Li-Pu Cui Jia-Qi Sun Si-Cong Li Xin-Ran Qin Hai-Dong Zou Chen-Hao Yang Pei-Yao Jin 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第3期537-544,共8页
●AIM:To identify the differential methylation sites(DMS)and their according genes associated with diabetic retinopathy(DR)development in type 1 diabetes(T1DM)children.●METHODS:This study consists of two surveys.A to... ●AIM:To identify the differential methylation sites(DMS)and their according genes associated with diabetic retinopathy(DR)development in type 1 diabetes(T1DM)children.●METHODS:This study consists of two surveys.A total of 40 T1DM children was included in the first survey.Because no participant has DR,retina thinning was used as a surrogate indicator for DR.The lowest 25%participants with the thinnest macular retinal thickness were included into the case group,and the others were controls.The DNA methylation status was assessed by the Illumina methylation 850K array BeadChip assay,and compared between the case and control groups.Four DMS with a potential role in diabetes were identified.The second survey included 27 T1DM children,among which four had DR.The methylation patterns of the four DMS identified by 850K were compared between participants with and without DR by pyrosequencing.●RESULTS:In the first survey,the 850K array revealed 751 sites significantly and differentially methylated in the case group comparing with the controls(|Δβ|>0.1 and Adj.P<0.05),and 328 of these were identified with a significance of Adj.P<0.01.Among these,319 CpG sites were hypermethylated and 432 were hypomethylated in the case group relative to the controls.Pyrosequencing revealed that the transcription elongation regulator 1 like(TCERG1L,cg07684215)gene was hypermethylated in the four T1DM children with DR(P=0.018),which was consistent with the result from the first survey.The methylation status of the other three DMS(cg26389052,cg25192647,and cg05413694)showed no difference(all P>0.05)between participants with and without DR.●CONCLUSION:The hypermethylation of the TCERG1L gene is a risk factor for DR development in Chinese children with T1DM. 展开更多
关键词 DNA methylation 850K array PYROSEQUENCING diabetic retinopathy type 1 diabetes CHILDREN
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动量轮卸载对环月卫星SMART-1轨道的影响和定轨策略 被引量:5
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作者 黄勇 胡小工 +1 位作者 董光亮 祝芙英 《飞行器测控学报》 2007年第5期62-66,共5页
动量轮卸载是卫星进行姿态控制的一种常用手段。通过对欧空局(ESA)首颗环月卫星SMART-1测轨资料的分析,计算了动量轮卸载对卫星轨道的影响,特别讨论了在动量轮卸载的精确信息未知时提高卫星定轨和预报精度的策略。计算表明,2006年5... 动量轮卸载是卫星进行姿态控制的一种常用手段。通过对欧空局(ESA)首颗环月卫星SMART-1测轨资料的分析,计算了动量轮卸载对卫星轨道的影响,特别讨论了在动量轮卸载的精确信息未知时提高卫星定轨和预报精度的策略。计算表明,2006年5月29日至6月2日期间,SMART-1多达19次的动量轮卸载过程使得其轨道位置变化达到3km。如果不考虑动量轮卸载的影响,定轨结果相比于ESA重建轨道的位置误差最大可达742m。本文利用分段常数的经验加速度模型来模制动量轮卸载产生的小推力。计算表明,即使动量轮卸载的精确信息未知,采用该方法也可显著提高定轨和预报精度,定轨位置误差最大下降到246m。计算还表明,经验加速度的合理选择(周期性、常数或线性经验加速度)决定定轨精度的改善程度。考虑到我国的首颗探月卫星“嫦娥一号”也将采用动量轮卸载的方式进行姿态控制,本文的结论对我国的探月工程有一定的借鉴意义。 展开更多
关键词 动量轮卸载 smart-1 轨道 定轨
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In situ growth of minimal Ir-incorporated CoxNi1-xO nanowire arrays on Ni foam with improved electrocatalytic activity for overall water splitting 被引量:5
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作者 Xiaoli Li Wenming Xue +3 位作者 Rong Mo Sui Yang Hongxing Li Jianxin Zhong 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第10期1576-1584,共9页
Exploration of cost-effective electrocatalysts for boosting the overall water-splitting efficiency is vitally important for obtaining renewable fuels such as hydrogen.Here,earth-abundant CoxNi1-xO nanowire arrays were... Exploration of cost-effective electrocatalysts for boosting the overall water-splitting efficiency is vitally important for obtaining renewable fuels such as hydrogen.Here,earth-abundant CoxNi1-xO nanowire arrays were used as a structural framework to dilute Ir incorporation for fabricating electrocatalysts for water splitting.Minimal Ir-incorporated CoxNi1-xO nanowire arrays were synthesized through the facile hydrothermal method with subsequent calcination by using Ni foam(NF)as both the substrate and source of Ni.The electrocatalytic water-splitting performance was found to crucially depend on the Ir content of the parent CoxNi1-xO nanowire arrays.As a result,for a minimal Ir content,as low as 0.57 wt%,the obtained Ir-CoxNi1-xO/NF electrodes exhibited optimal catalytic activity in terms of a low overpotential of 260 mV for the oxygen evolution reaction and 53 mV for the hydrogen evolution reaction at 10 mA cm?2 in 1 mol L–1 KOH.When used as bifunctional electrodes in water splitting,the current density of 10 mA cm–2 was obtained at a low cell voltage of 1.55 V.Density functional theory calculations revealed that the Ir-doped CoxNi1-xO arrays exhibited enhanced electrical conductivity and low Gibbs free energy,which contributed to the improved electrocatalytic activity.The present study presents a new strategy for the development of transition metal oxide electrocatalysts with low levels of Ir incorporation for efficient water splitting. 展开更多
关键词 CoxNi1-xO nanowire array Iridium incorporation ELECTROCATALYST Water splitting OVERPOTENTIAL
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In Situ Growth of 3D Hierarchical ZnO@Ni_xCo_(1-x)(OH)_y Core/Shell Nanowire/Nanosheet Arrays on Ni Foam for High-Performance Aqueous Hybrid Supercapacitors 被引量:1
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作者 Fumin Wang Mengchao Liu +2 位作者 Xubin Zhang Guojun Lv Mingshuai Sun 《Transactions of Tianjin University》 EI CAS 2018年第3期201-211,共11页
In this study, we designed and synthesized a novel battery-type electrode featuring three-dimensional(3D) hierarchical ZnO@Ni_xCo_(1-x)(OH)_y core/shell nanowire/nanosheet arrays arranged on Nifoam substrate via a two... In this study, we designed and synthesized a novel battery-type electrode featuring three-dimensional(3D) hierarchical ZnO@Ni_xCo_(1-x)(OH)_y core/shell nanowire/nanosheet arrays arranged on Nifoam substrate via a two-step protocol including a wet chemical process followed by electro-deposition. We then characterized its composition, structure and surface morphology by X-ray diff raction, energy-dispersive X-ray spectrometry(EDS), X-ray photoelectron spectroscopy, scanning electron microscopy(SEM), transmission electron microscopy, EDS elemental mapping. Our electrochemical measurements show that the ZnO@Ni_(0.67)Co_(0.33)(OH)_y electrode material exhibited a noticeably high specific capacity of as much as 255(mA ·h)/g at 1 A/g. Additionally, it demonstrated a superior rate capability, as well as an excellent cycling stability with 81.6% capacity retention over 2000 cycles at 5 A/g. This sample delivered a high energy density of 64 W·h/kg and a power density of 250 W/kg at a current density of 1 A/g. With such remarkable electrochemical properties, we expect the 3D hierarchical hybrid electrode material presented in this work to have promising applications for the next generation of energy storage systems. 展开更多
关键词 ZnO@NixCo1-x(OH)y Core/shell nanowire/nanosheet array Supercapacitor Ni foam
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欧洲探月计划的敲门砖——SMART-1 被引量:1
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作者 曹秀云 杜元清 《中国航天》 北大核心 2003年第12期32-34,共3页
关键词 欧洲 探月计划 smart-1 月球探测器 “小型先进技术研究任务” 法属圭亚那库鲁航天发射场 阿里安5运载火箭
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THE WAVELET TRANSFORM BASED PROCESSING MEANS FOR 1/f NOISE IN MILLIMETER WAVE FOCAL PLANE ARRAY
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作者 Zhang Yong Li Xingguo(Institute of Millimeter-Wave & Light-Wave Near Sensing Technology, Nanjing University of Science & Technology, Nanjing 210094) 《Journal of Electronics(China)》 1999年第4期343-349,共7页
After briefly introducing the characteristics of 1/f noise in millimeter wave focalplane array detectors, the paper analyses the relation of wavelet transform and 1/f noise in detail, suggests the fashion of decorrela... After briefly introducing the characteristics of 1/f noise in millimeter wave focalplane array detectors, the paper analyses the relation of wavelet transform and 1/f noise in detail, suggests the fashion of decorrelating 1/f noise using the wavelet transform and deduces the relative expressions. The results of computer simulation show good effectiveness. 展开更多
关键词 MILLIMETER wave FOCAL PLANE array 1/f noise WAVELET TRANSFORM Decorrelate
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Effects of Mitochondrial DNA Deletion and OSW-1 on PI3K-AKT Signaling Pathway PCR Array in SK-Hep1 Cells
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作者 Xichen Du Changshi Qian Xinglin Jin 《Chinese Medicine》 2019年第3期107-119,共13页
To investigate the effect of mitochondrial DNA deletion and OSW-1 on PI3K-AKT signaling pathway PCR Array in SK-Hep1 hepatocellular carcinoma cells, we prepared SK-Hep1 cells with mtDNA deletion, that is, p0SK Hep. Th... To investigate the effect of mitochondrial DNA deletion and OSW-1 on PI3K-AKT signaling pathway PCR Array in SK-Hep1 hepatocellular carcinoma cells, we prepared SK-Hep1 cells with mtDNA deletion, that is, p0SK Hep. Then the OSW-1 of 100 ng/L was used to intervene SK-Hep1 and p0SK-Hep1. RT-qPCR was used to detect the difference of gene expression on PI3K-AKT signaling pathway PCR Array in four groups of cells. The gene expression of TLR4, FOS and TSC2 markers in SK-Hep1 cells treated with OSW-1 were significantly increased. The gene expressions of PDPK1, GJA1, TLR4 and TSC2 markers were significantly increased in p0SK-Hep1 cells, and the gene expressions of IRAK1 and GJA1 markers were significantly increased in p0SK-Hep1 cells treated with OSW-1. OSW-1 mainly affects the genes related to TLR4 pathway on PI3K-AKT signaling pathway PCR Array in SK-Hep1 HCC cells. P0SK-Hep1 mainly affects the upstream PDK1 gene and downstream TSC2 gene of Akt on PI3K-AKT signaling pathway PCR Array, and also affects the gene expression of gap junction at the same time. 展开更多
关键词 MTDNA OSW-1 PI3K-AKT PCR array SK-Hep1 CELLS
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广西地区乙肝病毒/黄曲霉毒素B_1双暴露相关性肝细胞性肝癌微阵列比较基因组学的研究 被引量:7
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作者 齐鲁楠 陈圆圆 +4 位作者 陈祖舜 白涛 朱海 彭涛 黎乐群 《中国癌症防治杂志》 CAS 2013年第3期201-210,共10页
目的研究乙肝病毒/黄曲霉毒素B1双暴露相关性肝细胞性肝癌(hepatocellularcarcinoma,HCC)染色体遗传学畸变的特点。方法将32例手术切除经病理证实为HCC的癌组织,按照乙肝病毒与黄曲霉毒素的暴露情况分为4个亚组:A组为HBV(+)/... 目的研究乙肝病毒/黄曲霉毒素B1双暴露相关性肝细胞性肝癌(hepatocellularcarcinoma,HCC)染色体遗传学畸变的特点。方法将32例手术切除经病理证实为HCC的癌组织,按照乙肝病毒与黄曲霉毒素的暴露情况分为4个亚组:A组为HBV(+)/AFB,(+)10例;B组为HBV(+)/AFB1(-)10例;C组为HBV(-)/AFB1(+)6例;D组为HBV(-)/AFB1(-)6例。应用微阵列比较基因组杂交技术(ArrayCGH)检测分析其22对染色体DNA拷贝数的变化。结果32例HCC样本中,共发现573个染色体畸变区段(chromosomalaberrations,CNAs)。其中1q、4p、5p、6p、7p、8q、10p、17q、20p、20q和X主要表现为扩增区段;1p、2q、4q、8p、9p、10q、11q、13q、14q、16p、16q、17p、19p、19q、21q、22q和Y主要表现为缺失区段。同时,共检测出25个染色体发生高频畸变的区段(recurrentlyalteredregions,RARs),其中lq21.1-q44、5p13.2-p15.3、6p12.1-p25.2、7q11.2-q35、8q11.2-q24.3、17q12-q25.2、18q12.3-q22.3和x为高频率扩增区段,而lp31.1-p36.2、2q23.2-q37.2、4q12-q35.2、6q14.1-q26、8p12-p23.2、9p21.1-p24.2、10q21.3-q26.2、13q12.1-q21.1、14q21.3-q32.2、16p12.1-p13.2、16q12.1-q24.1、17p12-p1313、19p13.1-p13.3、19q13.2-q13.4、21q21.3-q22.2、22q11.2-q13.2和Y染色体为高频缺失区段。8p12-p23.2缺失的发生率在进展期HCC(TNM分期为Ⅲ~Ⅳ期)中明显高于早期HCC(TNM分期为I~Ⅱ期)(仁0.038)。4q12-q35.2、13q12.1-q21.1的缺失及7q21.1-q35的扩增发生率在A组中最高。Cox模型分析结果示:在单因素分析中AFP水平、肿瘤大小、TNM分期、BCLC分期、侵袭与转移的发生、8p12-p23.2的缺失以及19p13.1-p13.3的缺失等为影响患者无瘤生存时间的危险因素(P〈0.05).而在多因素分析中AFP水平、TNM分期以及8p12-p23.2的缺失等为影响患者无瘤生存时间的危险因素(P〈0.05o结论广西地区HCC染色体遗传学改变具有多样性,其中染色体19p13.1.p13-3的高频缺失可能为广西地区HCC特有的分子生物学特征之一。染色体8p12-p23.2的缺失可能为HCC的晚期事件,并且与患者的不良预后有关。染色体4q12-q35.2、13q12.1-q21.1缺失及7q21.1-q35扩增可能与HBV/AFB。双因素的协同致癌作用有关。 展开更多
关键词 肝肿瘤 乙肝病毒 黄曲霉毒素B1 染色体 array CGH
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西南地区普通小麦1BL/1RS易位系的DArT分子标记鉴定 被引量:2
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作者 张立异 王伟 +4 位作者 刘冬成 孙家柱 阳文龙 何庆才 张爱民 《麦类作物学报》 CAS CSCD 北大核心 2012年第5期832-838,共7页
为了准确了解小麦品系中1BL/1RS易位系的存在,利用7 000多个DArT分子标记(Diversityarrays technology,多样性微阵列技术)对87个普通小麦品系进行扫描,总共获得1 750个稳定的多样性的分子标记(P>80)。这些标记的多态性信息含量指数(P... 为了准确了解小麦品系中1BL/1RS易位系的存在,利用7 000多个DArT分子标记(Diversityarrays technology,多样性微阵列技术)对87个普通小麦品系进行扫描,总共获得1 750个稳定的多样性的分子标记(P>80)。这些标记的多态性信息含量指数(PIC)的范围是0.03~0.5,平均值为0.35(P>80)。根据DArT标记的可整合性,利用1B染色体上的DArT数据进行主坐标分析(Principal-Coordinates Analysis,PCoA),可以把实验材料划分为两个群,并且确定一个群是由1BL/1RS易位系组成,另一个群由非1BL/1RS易位系组成。同时,利用非加权组平均法(Unweighted pair-group method with arithmetic means,UPGMA)进行聚类分析,调查了材料之间的遗传关系,结果显示,实验材料同样聚集为两个群,一个群由1BL/1RS易位系组成,包含两个亚群;另一个群由非易位系组成,包含六个亚群。研究证实,DArT标记不仅可以调查小麦全基因组的遗传多样性,而且利用它的可整合性能够准确鉴定研究材料中的1BL/1RS易位系。 展开更多
关键词 普通小麦 DArT(Diversity array Technology)标记 1BL/1RS易位系 主坐标分析(PCoA Principal-Coordinates Analysis)
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Blocking of N-acetylglucosaminyltransferase V induces cellular endoplasmic reticulum stress in human hepatocarcinoma 7721 cells 被引量:7
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作者 Huan Fang Wei Huang +6 位作者 Ying Ying Xu Zong Hou Shen Chao Qun Wu Shou Yi Qiao Yan Xu Long Yu Hui Li Chen 《Cell Research》 SCIE CAS CSCD 2006年第1期82-92,共11页
N-acetylglucosaminyltransferase V (GnT-V) is an important tumorigenesis and metastasis-associated enzyme. To study its biofunction, the GnT-V stably suppressed cell line (GnT-V-AS/7721) was constructed from 7721 h... N-acetylglucosaminyltransferase V (GnT-V) is an important tumorigenesis and metastasis-associated enzyme. To study its biofunction, the GnT-V stably suppressed cell line (GnT-V-AS/7721) was constructed from 7721 hepatocarcinoma cells in previous study. In this study, cDNA array gene expression profiles were compared between GnT-V-AS/7721 and parental 7721 cells. The data indicated that GnT-V-AS/7721 showed a characteristic expression pattern consistent with the ER stress. The molecular mechanism of the ER stress was explored in GnT-V-AS/7721 by the analysis on key molecules in both two unfolded protein response (UPR) pathways. For ATF6 and Irel/XBP-1 pathway, it was evidenced by the up-regulation of BIP at mRNA and protein level, and the appearance of the spliced form ofXBP-1. As for PERK/eIF2α pathway, the activation of ER eIF2α kinase PERK was observed. To confirm the results from GriT-V-AS/7721 cells, the key molecules in the UPR were examined again in 7721 cells interfered with the GnT-V by the specific RNAi treatment. The results were similar with those from GnT-V-AS/7721, indicating that blocking of GnT-V can specifically activate ER stress in 7721 cells. Rate of 3H-Man incorporation corrected with rate of 3H-Leu incorporation in GnT-V-AS/7721 was down-regulated greatly compared with the control, which demonstrated the deficient function of the enzyme synthesizing N-glycans after GnT-V blocking. Moreover, the faster migrating form of chaperone GRP94 associated with the underglycosylation, and the extensively changed N-glycans structures of intracellular glycoproteins were also detected in GnT-V-AS/7721. These results supported the mechanism that blocking of GnT-V expression impaired functions of chaperones and N-glycan-synthesizing enzymes, which caused UPR in vivo. 展开更多
关键词 N-acetylglucosaminyltransferase V ER stress GLYCOPROTEIN cDNA array RNAi BIP XBP-1 PERK GRP94
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SFRP1基因启动子区甲基化与宫颈癌及癌前病变的相关性研究 被引量:4
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作者 胡丹妮 贾薇 +4 位作者 谭秋芬 李锋 杨安强 蒋金芳 潘晓琳 《石河子大学学报(自然科学版)》 CAS 2010年第3期325-329,共5页
应用MassARRAY DNA甲基化定量分析方法检测58例宫颈癌组织、57例CIN2/3组织、36例CIN1组织及28例正常对照组织中SFRP1基因启动子区各CpG位点甲基化,探讨SFRP1基因启动子区甲基化与宫颈癌演进及与HPV16感染的相关性。结果显示:2110个CpG... 应用MassARRAY DNA甲基化定量分析方法检测58例宫颈癌组织、57例CIN2/3组织、36例CIN1组织及28例正常对照组织中SFRP1基因启动子区各CpG位点甲基化,探讨SFRP1基因启动子区甲基化与宫颈癌演进及与HPV16感染的相关性。结果显示:2110个CpG单位中甲基化率低于30%的CpG单位1612个,占总数的76.4%;甲基化率大于80%的CpG单位为4.4%,多分布于CIN2/3和宫颈癌组织之中。其中SFRP1基因启动子区CpG12.13和CpG18位点的甲基化率宫颈癌组高于对照、CIN1和CIN2/3组,差异具有统计学意义(P<0.05)。CpG12.13和CpG18位点甲基化率与HPV16感染无相关性(P>0.05)。提示SFRP1基因在CpG12.13和CpG18位点上高甲基化可能与宫颈癌的演进相关。 展开更多
关键词 SFRP1 甲基化 HPV MASS array 宫颈癌
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Gene Expression Profiles Comparison between 2009 Pandemic and Seasonal H1N1 Influenza Viruses in A549 Cells 被引量:2
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作者 XIAO-XING YANG NING DU JIAN-FANG ZHOU ZI LI MIN WANG JUN-FENG GUO DA-YAN WANG YUE-LONG SHU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2010年第4期259-266,共8页
Objective To perform gene expression profiles comparison so that to identify and understand the potential differences in pathogenesis between the pandemic and seasonal A (H1N1) influenza viruses. Methods A549 cells ... Objective To perform gene expression profiles comparison so that to identify and understand the potential differences in pathogenesis between the pandemic and seasonal A (H1N1) influenza viruses. Methods A549 cells were infected with A/California/07/09 (H1N1) and A/GuangdongBaoan/51/08 (H1N1) respectively at the same MOI of 2 and collected at 2, 4, 8, and 24 h post infection (p.i.). Gene expression profiles of A549 cells were obtained using the 22 K Human Genome Oligo Array, and differentially expressed genes were analyzed at selected time points. Results Microarrays results indicated that both of the viruses suppressed host immune response related pathways including cytokine production while pandemic H1N1 virus displayed weaker suppression of host immune response than seasonal H1N1 virus. Observation on similar anti-apoptotic events such as activation of apoptosis inhibitor and down-regulation of key genes of apoptosis pathways in both infections showed that activities of promoting apoptosis were different in later stage of infection. Conclusion The immuno-suppression and anti-apoptosis events of pandemic H1N1 virus were similar to those seen by seasonal H1N1 virus. The pandemic H1N1 virus had an ability to inhibit biological pathways associated with cytokine responses, NK activation and macrophage recognition . 展开更多
关键词 Influenza A virus Pandemic H1N1 A549 Expression profiling array
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Joint 2D DOA and Doppler frequency estimation for L-shaped array using compressive sensing 被引量:4
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作者 WANG Shixin ZHAO Yuan +3 位作者 LAILA Ibrahim XIONG Ying WANG Jun TANG Bin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第1期28-36,共9页
A joint two-dimensional(2D)direction-of-arrival(DOA)and radial Doppler frequency estimation method for the L-shaped array is proposed in this paper based on the compressive sensing(CS)framework.Revised from the conven... A joint two-dimensional(2D)direction-of-arrival(DOA)and radial Doppler frequency estimation method for the L-shaped array is proposed in this paper based on the compressive sensing(CS)framework.Revised from the conventional CS-based methods where the joint spatial-temporal parameters are characterized in one large scale matrix,three smaller scale matrices with independent azimuth,elevation and Doppler frequency are introduced adopting a separable observation model.Afterwards,the estimation is achieved by L1-norm minimization and the Bayesian CS algorithm.In addition,under the L-shaped array topology,the azimuth and elevation are separated yet coupled to the same radial Doppler frequency.Hence,the pair matching problem is solved with the aid of the radial Doppler frequency.Finally,numerical simulations corroborate the feasibility and validity of the proposed algorithm. 展开更多
关键词 electronic warfare L-shaped array joint parameter estimation L1-norm minimization Bayesian compressive sensing(CS) pair matching
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Experiments on Exploration of Shallow Fine Structures and the Construction of the 1-D Velocity Model in the Pingtan Island,Fujian 被引量:1
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作者 GUO Yang XU Jiajun +4 位作者 LIN Chen JIN Xing YAO Huajian YANG Hongfeng CAI Huiteng 《Earthquake Research in China》 CSCD 2019年第2期265-275,共11页
112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a den... 112 short-period seismographs were set up in the 400 km^2 area of Pingtan Island and its surrounding areas in Fujian.The combined observations of the airgun source and ambient noise source were carried out using a dense array to receive the 387 airgun signals excited around the island and one month of continuous ambient noise recording.The 1-D P-wave and S-wave shallow velocity model of Pingtan Island is obtained by the inversion of the airgun body wave’s first arrival time data,and the reliability of the velocity model is verified by using the surface wave phase velocity dispersion curve,which can provide initial model for subsequent 3-D imaging.The experimental results show that this experiment is a successful demonstration of local scale green non-destructive detection,which can provide basic data for shallow surface structure research and strong vibration simulation of the Pingtan Island. 展开更多
关键词 PINGTAN ISLAND Fujian DENSE array Airgun AMBIENT noise 1-D VELOCITY model
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A Zn(Ⅱ) Coordination Polymer Based on a Flexible Polycarboxylate Ligand 5-(4-Hydroxypyridinium-1-ylmethyl)-isophthalic Acid: Synthesis, Structure, and Property 被引量:1
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作者 李付安 杨维春 李青彬 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第4期645-652,共8页
A Zn(Ⅱ) supramolecular coordination polymer, {[Zn2(L)2(m-bix)(H20)]6H2O}n(1), with an interesting 1D→2D polythreading array from a flexible and angular organic aromaticpolycarboxylate ligand 5-(4-hydroxyp... A Zn(Ⅱ) supramolecular coordination polymer, {[Zn2(L)2(m-bix)(H20)]6H2O}n(1), with an interesting 1D→2D polythreading array from a flexible and angular organic aromaticpolycarboxylate ligand 5-(4-hydroxypyridinium-l-ylmethyl)isophthalic acid (H2L), and N-donorligand 1,3-bis(imidazol-l-ylmethyl)benzene (m-bix), has been obtained under hydrothermalconditions and characterized by elemental analysis, powder X-ray diffraction (PXRD), IR, thermalgravimetric analyses (TGA) and single-crystal X-ray diffraction. In 1, the Zn(Ⅱ) center has twocoordination geometries. One exhibits a trigonal bipyramidal coordination sphere, and the other isa tetrahedral geometry; L2- has two different coordination modes, with one connecting three Zn(Ⅱ)ions through two monodentate carboxylate groups and the monodentate hydroxyl group, and theother bridging two Zn(Ⅱ) ions through two carboxylate groups. The L2- anions connect the Zn(Ⅱ)centers forming an infinite 1D tubular structure. These 1D tubes are interconnected by the m-bixspacers to form a 2D framework. Such 2D layers are further assembled into a 3D supramolecularnetwork via hydrogen bonds. Meanwhile, the luminescent property of 1 has also been investigatedin detail. 展开更多
关键词 5-(4-hydroxypyridinium-1-ylmethyl)isophthalic acid 1 3-bis(imidazol-1-ylmethyl)benzene ZINC PXRD 1D→2D polythreading array
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On a Grouping Method for Constructing Mixed Orthogonal Arrays 被引量:1
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作者 Chung-Yi Suen 《Open Journal of Statistics》 2012年第2期188-197,共10页
Mixed orthogonal arrays of strength two and size smn are constructed by grouping points in the finite projective geometry PG(mn-1, s). PG(mn-1, s) can be partitioned into [(smn-1)/(sn-1)](n-1)-flats such that each (n-... Mixed orthogonal arrays of strength two and size smn are constructed by grouping points in the finite projective geometry PG(mn-1, s). PG(mn-1, s) can be partitioned into [(smn-1)/(sn-1)](n-1)-flats such that each (n-1)-flat is associated with a point in PG(m-1, sn). An orthogonal array Lsmn((sn)(smn-)(sn-1) can be constructed by using (smn-1)/( sn-1) points in PG(m-1, sn). A set of (st-1)/(s-1) points in PG(m-1, sn) is called a (t-1)-flat over GF(s) if it is isomorphic to PG(t-1, s). If there exists a (t-1)-flat over GF(s) in PG(m-1, sn), then we can replace the corresponding [(st-1)/(s-1)] sn-level columns in Lsmn((sn)(smn-)(sn-1) by (smn-1)/( sn-1) st -level columns and obtain a mixed orthogonal array. Many new mixed orthogonal arrays can be obtained by this procedure. In this paper, we study methods for finding disjoint (t-1)-flats over GF(s) in PG(m-1, sn) in order to construct more mixed orthogonal arrays of strength two. In particular, if m and n are relatively prime then we can construct an Lsmn((sm)smn-1/sm-1-i(sn-1)/ (s-1)( sn) i(sm-1)/ s-1) for any 0i(smn-1)(s-1)/( sm-1)( sn-1) New orthogonal arrays of sizes 256, 512, and 1024 are obtained by using PG(7,2), PG(8,2), and PG(9,2) respectively. 展开更多
关键词 FINITE field FINITE PROJECTIVE geometry (t-1)-flat over GF(s) in PG(m-1 sn ) Geometric ORTHOGONAL array Matrix representation Minimal polynomial ORTHOGONAL main-effect plan PRIMITIVE element Tight.
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Controlling DNA Bundle Size and Spatial Arrangement in Selfassembled Arrays on Superhydrophobic Surface
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作者 Gabriele Ciasca Massimiliano Papi +8 位作者 Valentina Palmieri Michela Chiarpotto Simone Di Claudio Adele De Ninno Ennio Giovine Gaetano Campi Annamaria Gerardino Luca Businaro Marco De Spirito 《Nano-Micro Letters》 SCIE EI CAS 2015年第2期146-151,共6页
The use of superhydrophobic surfaces(SHSs) is now emerging as an attractive platform for the realization of one-dimensional(1D) nanostructures with potential applications in many nanotechnological and biotechnological... The use of superhydrophobic surfaces(SHSs) is now emerging as an attractive platform for the realization of one-dimensional(1D) nanostructures with potential applications in many nanotechnological and biotechnological fields.To this purpose, a strict control of the nanostructures size and their spatial arrangement is highly required. However, these parameters may be strongly dependent on the complex evaporation dynamics of the sessile droplet on the SHS. In this work, we investigated the effect of the evaporation dynamics on the size and the spatial arrangement of self-assembled 1D DNA bundles. Our results reveal that different arrangements and bundle size distributions may occur depending on droplet evaporation stage. These results contribute to elucidate the formation mechanism of 1D nanostructures on SHSs. 展开更多
关键词 SUPERHYDROPHOBICITY DNA array Cassie state Wenzel state 1D nanostructures SELF-ASSEMBLY
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Fast inversion of array laterolog measurements in an axisymmetric medium
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作者 Hu Song Chen Long Wang Jin 《Applied Geophysics》 SCIE CSCD 2019年第4期539-548,562,共11页
The array laterolog is an important tool for complex formation logging evaluation due to its high resolution and large detection depth.However,its logging responses are seriously affected by leakage events due to the ... The array laterolog is an important tool for complex formation logging evaluation due to its high resolution and large detection depth.However,its logging responses are seriously affected by leakage events due to the surrounding rock and by mud invasion.These factors must be considered when inverting array lateral logging data,so that the inversion results reflect the true formation conditions as much as possible.The difficulties encountered in the inversion of array lateral logging data are:too many inversion parameters cause the calculation of the Jacobian matrix to be difficult and the time required to select the initial inversion values due to the slow forward-modeling speed.In this paper,we develop a fast processing method for array laterolog data.First,it is important to clearly define the main controlling factors for the array laterolog response,such as thickness,the surrounding rock,and invasion.Second,based on a depth-window technique,processing the array laterolog data for the entire well is transformed into multiple 2 D inversions of the layers using a series of continuous depth windows.For each formation in a depth window,combined with the1 D equivalent fast-forward algorithm,rapid extraction of the radial resistivity profile of the formation is achieved.Finally,the 1 D inversion result is used as the initial state to further eliminate the influence of surrounding rocks and layer thicknesses on the apparent resistivity response.Numerical simulation results show that the factors affecting the response of the array laterolog are the invasion properties,the layer thicknesses,and the surrounding rocks;the windowing technique greatly reduces the number of inversion parameters needed and improves the inversion speed.A real application of the method shows that 2 D inversion can rapidly reconstruct the actual resistivity distribution and improve the accuracy of reservoir saturation calculations. 展开更多
关键词 array laterolog 2D inversion invasion profile windowing treatment 1D inversion
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Implementation of motion estimator algorithm with 1/4 pixel accuracy based on FPGA
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作者 向厚振 王鹏 +1 位作者 姚娟 张志杰 《Journal of Measurement Science and Instrumentation》 CAS 2012年第4期341-344,共4页
After research on the motion estimation algorithm in video coding, a motion estimator algorithm with 1/4 pixel ac- curacy is implemented based on fie/d-programmable gate array (FPGA). The motion estimation algorithm... After research on the motion estimation algorithm in video coding, a motion estimator algorithm with 1/4 pixel ac- curacy is implemented based on fie/d-programmable gate array (FPGA). The motion estimation algorithm module is made up of the 1[4 pixel interpolation module with serial input and parallel output, the three step search module and the block match- ing module, which can use relatively less Wiener filters for interpolation operation. Experiment results show that the hard- ware design has less consumption of the logical resource, higher stability and lower power consumption. 展开更多
关键词 H. 264/AVC 1/4 pixel three-step search motion estimation field-programmable gate array (FPGA)
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