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表达Strep-tag II的重组塞内卡病毒的构建与鉴定
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作者 史家宝 蒙靓 +4 位作者 肖培宇 范峻豪 安同庆 王海伟 于力 《中国预防兽医学报》 CAS CSCD 北大核心 2024年第2期140-146,共7页
为构建表达Strep-tag II的重组塞内卡病毒(SVA),本研究在感染性cDNA克隆p SVA-I212V/S460L的基础上,采用重叠延伸PCR扩增Strep-tag II并采用无缝克隆法将其插入SVA VP1基因C端,构建感染性cDNA克隆,命名为p SVA-Strep,并采用双酶切和测... 为构建表达Strep-tag II的重组塞内卡病毒(SVA),本研究在感染性cDNA克隆p SVA-I212V/S460L的基础上,采用重叠延伸PCR扩增Strep-tag II并采用无缝克隆法将其插入SVA VP1基因C端,构建感染性cDNA克隆,命名为p SVA-Strep,并采用双酶切和测序鉴定正确后,将p SVA-Strep转染BHK-21细胞拯救重组病毒,收集病变细胞上清,并将含有病毒的细胞上清和野生型SVA(SVA-WT)分别感染BHK-21细胞,以未感染病毒的BHK-21细胞作为阴性对照,感染后24 h分别以鼠源SVA VP2蛋白单克隆抗体(MAb)5D10(1∶1000)、鼠源Strep-tag II MAb(1∶2000)作为一抗,以FITC标记的山羊抗小鼠Ig G(1∶2000)为二抗,采用间接免疫荧光试验(IFA)对重组病毒鉴定。IFA结果显示,以鼠源SVA VP2蛋白MAb 5D10为一抗,SVA-WT和重组病毒感染的细胞均出现绿色荧光,以Strep-tag II MAb作为一抗时,仅有重组病毒感染的细胞出现绿色荧光,经SVA-WT感染的BHK-21细胞及阴性对照细胞均无绿色荧光,表明拯救了Strep-tag II标记的重组病毒,并将其命名为r SVA-Strep。将r SVA-Strep在BHK-21细胞中连续传10代,每隔2代采用引物VP1-F/R经PCR鉴定并对第10代重组病毒的VP1基因测序以鉴定r SVA-Strep的遗传稳定性。结果显示,每隔两代的重组病毒经PCR扩增后均出现约780 bp的目的条带,第10代重组病毒扩增的VP1基因测序结果显示Strep-tag II基因仍在重组病毒中,且无基因突变,表明r SVA-Strep的遗传稳定性较强;将SVA-WT和r SVA-Strep分别以MOI 0.01感染BHK-21细胞,在感染后4 h、8 h、12 h、24 h、36 h、48 h和72 h收获病毒测定病毒滴度并绘制生长曲线,结果显示在病毒感染36 h内r SVA-Strep和SVA-WT生长动力学基本一致,表明Strep-tag II的引入在病毒感染36 h内对SVA的复制基本无影响。采用0.2%甲醛充分灭活r SVA-Strep,并利用Strep-TactinRXT Purification纯化试剂盒纯化该灭活病毒,将r SVA-Strep灭活病毒上清加至Strep-Tactin亲和层析柱,分别用不同体积洗脱缓冲液依次洗脱病毒并通过western blot鉴定病毒的纯化效果。对纯化过程中不同洗脱液洗脱病毒的western blot结果显示,不同体积的洗脱液中E1、E2和E3均出现VP0和VP2两条带,且E1和E2的条带最明显,表明洗脱缓冲液的最佳洗脱体积约为2.2 CV;以上结果表明r SVA-Strep可通过Strep-Tactin亲和层析柱一步法纯化。本研究在SVA中插入Strep-tag II标签,为SVA灭活疫苗的快速纯化提供技术手段,也为其他病原的快速纯化方法的建立提供参考。 展开更多
关键词 塞内卡病毒 Strep-tag II 感染性克隆 抗原纯化
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Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory
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作者 Yang Su Ze-Yu Li +3 位作者 Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期198-207,共10页
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair... Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data. 展开更多
关键词 Nuclear fission Density functional theory Pairing force Potential energy surfaces fission fragment distribution
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Apatite Fission Track Thermochronology of Granite from the Xiazhuang Uranium Ore Field,South China:Implications for Exhumation History and Ore Preservation
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作者 SUN Yue CHEN Zhengle +4 位作者 PAN Jiayong HUO Hailong LI Haidong SUN Junjie XU Guangchun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期430-440,共11页
Xiazhuang uranium ore field,located in the southern part of the Nanling Metallogenic Belt,is considered one of the largest granite-related U regions in South China.In this paper,we contribute new apatite fission track... Xiazhuang uranium ore field,located in the southern part of the Nanling Metallogenic Belt,is considered one of the largest granite-related U regions in South China.In this paper,we contribute new apatite fission track data and thermal history modeling to constrain the exhumation history and evaluate preservation potential of the Xiazhuang Uranium ore field.Nine Triassic outcrop granite samples collected from different locations of Xiazhuang Uranium ore field yield AFT ages ranging from 43 to 24 Ma with similar mean confined fission track lengths ranging from 11.8±2.0 to 12.9±1.9μm and Dpar values between 1.01 and 1.51μm.The robustness time-temperature reconstructions of samples from the hanging wall of Huangpi fault show that the Xiazhuang Uranium ore field experienced a time of monotonous and slow cooling starting from middle Paleocene to middle Miocene(~60-10 Ma),followed by relatively rapid exhumation in the late Miocene(~10-5 Ma)and nearly thermal stability in the Pliocene-Quaternary(~5-0 Ma).The amount of exhumation after U mineralization since the Middle Paleogene was estimated as~4.3±1.8 km according to the integrated thermal history model.Previous studies indicate that the ore-forming ages of U deposits in the Xiazhuang ore field are mainly before Middle Paleocene and the mineralization depths are more than 4.4±1.2 km.Therefore,the exhumation history since middle Paleocene plays important roles in the preservation of the Xiazhuang Uranium ore field. 展开更多
关键词 apatite fission track exhumation history ore preservation Xiazhuang Uranium ore field South China
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Differential Expression Analysis of Proteins Regulated by Rare Earth Cerium in Soybean Leaves at Seedling Stage
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作者 Ren Hongyu Zhang Tianren +3 位作者 Miao Yanli Li Haoyang Zhang Shuying Zhang Xingwen 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第1期42-52,共11页
This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, ... This study was to explore the functional mechanism of rare earth regulating soybean leaves and the characteristics and functions of differentially expressed proteins under the regulation of rare earth. In this study, Dongnong 42 was used as material, and 30 mg·L^(-1) CeCl_(3) solution was sprayed on soybean leaves at the seedling stage. Tandem mass tag(TMT) quantitative proteomics technique and bioinformatics analysis were used to identify soybean leaf proteins. A total of 8 510 proteins were identified, and 127 differentially expressed proteins(DEPs) in response to rare earth cerium regulation were identified, among which 64 were upregulated and 63 were down-regulated. The gene ontology(GO) annotation indicated that DEPs were mainly involved in metabolic process, cellular process, response to stimulus, biological regulation, and response to a stimulus;DEPs in cell module categories were mainly involved in cells, cell part, organelle, membrane, membrane part, organelle par, and protein-containing complex;DEPs in molecular functional categories were mainly involved in catalytic activity, binding and antioxidant activity. Kyoto encyclopedia of genes and genomes(KEGG) pathway significantly enriched starch and sucrose metabolism, glycolysis/gluconeogenesis, galactose metabolism, pentose phosphate pathway, and MAPK signaling pathway-plant. These DEPs were mainly involved in photosynthesis, glucose metabolism and stress response. Forty-six differential protein interaction networks were identified by protein interaction network analysis. This experiment provided a reference for studies of the mechanism of rare earth cerium regulating soybean leaf function from the proteomic perspective. 展开更多
关键词 rare earth soybean proteomics tandem mass tag(TMT)
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Serum proteins differentially expressed in gestational diabetes mellitus assessed using isobaric tag for relative and absolute quantitation proteomics
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作者 Wei-Li Cao Cui-Ping Yu Ling-Li Zhang 《World Journal of Clinical Cases》 SCIE 2024年第8期1395-1405,共11页
BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients a... BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients and their altered expression in the serum,proteomics techniques were deployed to detect the differentially expressed proteins(DEPs)of in the serum of GDM patients to further explore its pathogenesis,and find out possible biomarkers to forecast GDM occurrence.METHODS Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria.Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation,and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry.Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis,and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA).RESULTS Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDMgravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteinsassociated with lipid metabolism, coagulation cascade activation, complement system and inflammatory responsein the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serumof GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk ofgestation.CONCLUSION GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complementsystem and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM. 展开更多
关键词 Gestational diabetes mellitus Liquid chromatography-tandem mass spectrometry Isobaric tag for relative and absolute quantitation PROTEOMICS BIOMARKER
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34.TAG·西海美术馆:面朝大海的艺术长廊
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作者 张路峰 《建筑师》 2024年第2期150-152,共3页
设计:让·努维尔事务所地点:山东青岛西海岸新区时间:2012—2021年规模:17000 m^(2)TAG·西海美术馆位于一座半岛的海边,远离市区^([1,2])。从规划意图看,整个项目由美术馆和艺术工坊两部分组成,但由于工坊部分处于停工状态,艺... 设计:让·努维尔事务所地点:山东青岛西海岸新区时间:2012—2021年规模:17000 m^(2)TAG·西海美术馆位于一座半岛的海边,远离市区^([1,2])。从规划意图看,整个项目由美术馆和艺术工坊两部分组成,但由于工坊部分处于停工状态,艺术社区氛围尚未形成,作为主体建筑的美术馆便成了荒野中的孤独存在,公众可达性较差(图1)。尽管如此,从设计研究角度,这座美术馆仍有许多精彩看点值得关注。 展开更多
关键词 美术馆 让·努维尔 社区氛围 主体建筑 青岛西海岸新区 可达性 艺术长廊 tag
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TAG HEUER 竞速激情
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作者 Chaos 《钟表》 2024年第3期29-31,共3页
继去年以卡莱拉系列Skipper计时码表的精钢版本标志着品牌重返帆船运动与航海领域之后,TAG Heuer泰格豪雅如今欣然发布一款以18K 5N玫瑰金打造的全新版本。金质的Skipper计时码表与精钢版本类似,同样基于2023年前期为纪念卡莱拉系列计... 继去年以卡莱拉系列Skipper计时码表的精钢版本标志着品牌重返帆船运动与航海领域之后,TAG Heuer泰格豪雅如今欣然发布一款以18K 5N玫瑰金打造的全新版本。金质的Skipper计时码表与精钢版本类似,同样基于2023年前期为纪念卡莱拉系列计时码表60周年推出且热销的“玻璃盒”(glassbox)设计,并搭载品牌自制机心Heuer 02(型号:TH20-06),这是一款为帆船赛计时而特别调整的Heuer 02机心。 展开更多
关键词 tag 帆船运动 玫瑰金 航海领域 帆船赛
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Connotea中Social Tagging机制研究 被引量:9
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作者 张玫 张晓林 《现代图书情报技术》 CSSCI 北大核心 2007年第7期1-4,共4页
选取Connotea为研究对象,统计分析标签、被标引资源、标引者两两关联关系,发现标签覆盖资源范围较广,标签共现现象突出,部分用户标引活跃,资源平均标签数较低,用户对内容关注度规律性转移,科研领域的用户比较多地使用规范词。提出增加... 选取Connotea为研究对象,统计分析标签、被标引资源、标引者两两关联关系,发现标签覆盖资源范围较广,标签共现现象突出,部分用户标引活跃,资源平均标签数较低,用户对内容关注度规律性转移,科研领域的用户比较多地使用规范词。提出增加标引词结构关联和细粒内容定位标引。 展开更多
关键词 Connotea SOCIAL tagging Folksonomy标签 用户行为
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国外Social Tagging研究群体分析 被引量:2
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作者 徐晨 《情报杂志》 CSSCI 北大核心 2013年第5期138-144,共7页
基于抽取的国外知名数据库的学术文献,分析探讨Social Tagging研究群体的学科特征和研究视角。结果表明当前Social Tagging的研究群体主要局限于信息科学与计算机科学,且未形成居于统治权威地位的研究团体和研究人员。自从Social Taggin... 基于抽取的国外知名数据库的学术文献,分析探讨Social Tagging研究群体的学科特征和研究视角。结果表明当前Social Tagging的研究群体主要局限于信息科学与计算机科学,且未形成居于统治权威地位的研究团体和研究人员。自从Social Tagging产生以来,"Social Tagging的组成功能"的研究一直是Social Tagging的基础性研究维度,不过随着应用深入发展,研究维度逐步转而融合信息检索和人机交互这两个相关领域知识分析"Tagger的行为及Social Tagging的界面设计"和"Social Tagging自身的组织和使用"这两个主要研究维度。 展开更多
关键词 SOCIAL tagging 研究群体 文献计量学 合作网络
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利用MRI Tagging分析β受体阻滞剂对左室心肌运动的影响
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作者 周莹 邹琳 +6 位作者 李铁岩 费青青 张月瑜 吴晶嘉 丁婷 戚晨雯 李腾腾 《中国心血管病研究》 CAS 2017年第9期837-840,I0003,I0004,共6页
目的 探讨不同剂量β受体阻滞剂对左室心肌运动特征的影响及其作用机制.方法 13名志愿者注射不同剂量的短效β受体阻滞剂Esmolol,每个注射剂量起效4 min后利用MRI Tagging对左室心肌圆周向收缩运动、放射向收缩运动及长轴收缩运动进行... 目的 探讨不同剂量β受体阻滞剂对左室心肌运动特征的影响及其作用机制.方法 13名志愿者注射不同剂量的短效β受体阻滞剂Esmolol,每个注射剂量起效4 min后利用MRI Tagging对左室心肌圆周向收缩运动、放射向收缩运动及长轴收缩运动进行磁化标记追踪,对获得的心肌运动结果进行心肌最大收缩程度、达到最大收缩时间、收缩速度及心肌做功分析.结果 注射小剂量Esmolol(5~25 μg·kg-1·min^-1)时,心肌运动程度增加,所需时间缩短,心肌做功增加;而当剂量增加至50~150 μg·kg-1·min^-1时,心肌运动明显较未用药时减弱,可以看到β受体阻滞剂Esmolol的负性肌力作用开始显现.结论 小剂量β受体阻滞剂与大剂量相比,更易对心肌运动产生正性肌力作用,这可能与不同种类心肌细胞表面β受体分布差异有关. 展开更多
关键词 心肌细胞 Β受体阻滞剂 MRI标记
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Apatite fission track thermochronology in the Kuluketage and Aksu areas,NW China:Implication for tectonic evolution of the northern Tarim 被引量:8
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作者 Zhiyong Zhang Wenbin Zhu +2 位作者 Dewen Zheng Bihai Zheng Wei Yang 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第2期171-180,共10页
Tarim Precambrian bedrocks are well exposed in the Kuluketage and Aksu areas, where twenty four samples were taken to reveal the denudation history of the northern Tarim Craton. Apatite fission track dating and therma... Tarim Precambrian bedrocks are well exposed in the Kuluketage and Aksu areas, where twenty four samples were taken to reveal the denudation history of the northern Tarim Craton. Apatite fission track dating and thermal history modeling suggest that the northern Tarim experienced multi-stage cooling events which were assumed to be associated with the distant effects of the Cimmerian orogeny and India-Eurasia collision in the past. But the first episode of exhumation in the northern Tarim, occurring in the mid-Permian to Triassic, is here suggested to be induced by docking of the Tarim Craton and final amalgamation of the Central Asian Orogenic Belt. The cooling event at ca. 170 Ma may be triggered by the Qiangtang-Eurasia collision. Widespread Cretaceous exhumation could be linked with docking of the Lhasa terrane in the late Jurassic. Cenozoic reheating and recooling likely occurred because of the northpropagating stress, however, this has not affected the northern Tarim much because the Tarim is characterized by rigid block-like motion. 展开更多
关键词 Tarim Craton The Kuluketage area Aksu Precambrian blueschist Apatite fission track Thermo-tectonic evolution
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Molecular tagging techniques and their applications to the study of complex thermal flow phenomena1,211 被引量:5
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作者 Fang Chen Haixing Li Hui Hu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2015年第4期425-445,共21页
This review article reports the recent progress in the development of a new group of molecule-based flow diagnostic techniques, which include molecular tag- ging velocimetry (MTV) and molecular tagging thermometry ... This review article reports the recent progress in the development of a new group of molecule-based flow diagnostic techniques, which include molecular tag- ging velocimetry (MTV) and molecular tagging thermometry (MTT), for both qualitative flow visualization of thermally induced flow structures and quantitative whole-field mea- surements of flow velocity and temperature distributions. The MTV and MTT techniques can also be easily combined to result in a so-called molecular tagging velocimetry and ther- mometry (MTV&T) technique, which is capble of achieving simultaneous measurements of flow velocity and temperature distribution in fluid flows. Instead of using tiny particles, the molecular tagging techniques (MTV, MTT, and MTV&T) use phosphorescent molecules, which can be turned into long-lasting glowing marks upon excitation by photons of appropriate wavelength, as the tracers for the flow veloc- ity and temperature measurements. The unique attraction and implementation of the molecular tagging techniques are demonstrated by three application examples, which include: (1) to quantify the unsteady heat transfer process from a heated cylinder to the surrounding fluid flow in order to exam- ine the thermal effects on the wake instabilities behind the heated cylinder operating in mixed and forced heat convec- tion regimes, (2) to reveal the time evolution of unsteady heat transfer and phase changing process inside micro-sized, icing water droplets in order to elucidate the underlying physics pertinent to aircraft icing phenomena, and (3) to achievesimultaneous droplet size, velocity and temperature measure- ments of "in-flight" droplets to characterize the dynamic and thermodynamic behaviors of flying droplets in spray flows. 展开更多
关键词 Molecular tagging velocimetry Molecular tagging thermometry Wake instabilities behindthe heated cylinder Aircraft icing Icing physics of waterdroplets Dynamics and thermodynamics of flying dropletsin spray flows
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Late Mesozoic Thermotectonic Evolution of the Jueluotage Range,Eastern Xinjiang,Northwest China:Evidence from Apatite Fission Track Data 被引量:4
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作者 ZHU Wenbin WAN Jinglin +5 位作者 SHU Liangshu ZHANG Zhiyong SU Jinbao SUN Yah GUO Jichun ZHANG Xueyun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第2期348-357,共10页
Although many authors have emphasized the Cenozoic history of deformation, exhumation and cooling in the Tiaushan area related to the India-Asia collision, very little is known about the Mesozoic history of compressio... Although many authors have emphasized the Cenozoic history of deformation, exhumation and cooling in the Tiaushan area related to the India-Asia collision, very little is known about the Mesozoic history of compression and uplift within the Tianshan. In order to obtain information about the Mesozoic exhumation history and processes of cooling in eastern Tianshan, fission track methods on apatite were used. Sampling was made in the Jueluotage Range. Three samples (Z001-Z003) were taken from granite in borehole ZK6301 of Yandong pluton; the ages range from 97.0 to 87.6 Ma that are much younger than the pluton age which was dated by U-Pb zircon at 334±2 Ma. Two samples in northern piedmont of the Jueluotage Range were collected from Jurassic strata in Dikaner (DK001) and Dananhu (D001) whose ages are 91.5 and 93.4 Ma respectively. The average apparent exhumation rate is 0.039 nun/a calculated by extrapolation on the basis of Yandong samples, indicating an extremely slow exhumation in the Jueluotage Range since the Late Cretaceous. Two Jurassic samples reached the maximum depths after deposition and experienced the maximum temperatures of ca. 105 and 108℃ until the late Early Cretaceous before a period of cooling and exhumation occurred at 114 and 106 Ma. 展开更多
关键词 Jueluotage Range APATITE fission track EXHUMATION cooling thermal modeling XINJIANG
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Late Cretaceous-Cenozoic Multi-Stage Denudation at the Western Ordos Block: Constraints by the Apatite Fission Track Dating on the Langshan 被引量:3
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作者 CUI Xianyue ZHAO Qihua +5 位作者 ZHANG Jin WANG Yannan ZHANG Beihang NIE Fengjun QU Junfeng ZHAO Heng 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期536-555,共20页
The apatite fission track dating of samples from the Dabashan (i.e., the Langshan in the northeastern Alxa Block) by the laser ablation method and their thermal history modeling of AFT ages are conducted in this stu... The apatite fission track dating of samples from the Dabashan (i.e., the Langshan in the northeastern Alxa Block) by the laser ablation method and their thermal history modeling of AFT ages are conducted in this study. The obtained results and lines of geological evidence in the study region indicate that the Langshan has experienced complicated tectonic-thermal events during the the Late Cretaceous-Cenozoic. Firstly, it experienced a tectonic-thermal event in the Late Cretaceous (-90-70 Ma). The event had little relation with the oblique subduction of the Izanagi Plate along the eastern Eurasian Plate, but was related to the Neo-Tethys subduction and compression between the Lhasa Block and Qiangtang Block. Secondly, it underwent the dextral slip faulting in the Eocene (-50-45 Ma). The strike slip fault may develop in the same tectonic setting as sinistral slip faults in southern Mongolia and thrusts in West Qinling to the southwest Ordos Block in the same period, which is the remote far-field response to the India-Eurasia collision. Thirdly, the tectonic thermal event existed in the late Cenozoic (since -10 Ma), thermal modeling shows that several samples began their denudation from upper region of partial annealing zone (PAZ), and the denudation may have a great relationship with the growth of Qinghai-Tibetan Plateau to the northeast. In addition, the AFT ages of Langshan indicate that the main body of the Langshan may be an upper part of fossil PAZ of the Late Cretaceous (-70 Ma). The fossil PAZ were destroyed and deformed by tectonic events repeatedly in the Cenozoic along with the denudation. 展开更多
关键词 apatite fission track cooling history thermal modeling Late Cretaceous-Cenozoic Langshan
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The Detectability for the Myocardial Fibrosis by Tagging Imaging on Cardiovascular Magnetic Resonance 被引量:1
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作者 Atsushi K. Kono Pierre Croisille +6 位作者 Tatsuya Nishii Katsusuke Kyotani Koya Nishiyama Mayumi Shigeru Sachiko Takamine Sei Fujiwara Kazuro Sugimura 《Open Journal of Radiology》 2014年第1期1-8,共8页
Purpose: Myocardial fibrosis causes cardiac dysfunction, arrhythmias, and sudden death. Tagging imaging on cardiovascular MR can measure the intra-myocardial motion from the dynamic deformation of lines superimposed o... Purpose: Myocardial fibrosis causes cardiac dysfunction, arrhythmias, and sudden death. Tagging imaging on cardiovascular MR can measure the intra-myocardial motion from the dynamic deformation of lines superimposed on the myocardium. The purpose of this study was to evaluate the detectability of myocardial fibrosis using tagging imaging and to compare this with conventional cine imaging. Materials and Methods: We reviewed 4 normal control (NML) subjects, 4 patients with myocarditis (MYO), and 4 patients with old myocardial infarction (ICM). We measured circumferential strain (Ecc) from tagging imaging, and regional wall thickening (rWT) from cine imaging. Fibrosis was determined from a late gadolinium enhancement (LGE) image. We evaluate diagnostic performance by comparing values of the area under curve (AUC) using ROC analysis. Results: Mean values of Ecc and rWT decreased in the area of LGE both in MYO and ICM patients. AUC values of Ecc and rWT in all subjects were 0.98 and 0.84, respectively (p < 0.0001). These values in MYO patients were 0.95 and 0.72 (p = 0.007), respectively, and 0.99 and 0.75, respectively, in ICM patients (p = 0.0008). Conclusions: Both Ecc and rWT decreased in the area with fibrosis in the patients with MYO and ICM. Tagging imaging showed better detectability of myocardial fibrosis than did cine imaging. 展开更多
关键词 tagging IMAGING Late GADOLINIUM Enhancement MYOCARDIAL FIBROSIS CARDIOVASCULAR Magnetic Resonance
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Unified Framework of Performing Chinese Word Segmentation and Part-of-Speech Tagging 被引量:3
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作者 Zhang Kaixu Sun Maosong 《China Communications》 SCIE CSCD 2012年第3期1-9,共9页
The paper proposes a unified framework to combine the advantages of the fast one-at-a-time approach and the high-performance all-at-once approach to perform Chinese Word Segmentation(CWS) and Part-of-Speech(PoS) taggi... The paper proposes a unified framework to combine the advantages of the fast one-at-a-time approach and the high-performance all-at-once approach to perform Chinese Word Segmentation(CWS) and Part-of-Speech(PoS) tagging.In this framework,the input of the PoS tagger is a candidate set of several CWS results provided by the CWS model.The widely used one-at-a-time approach and all-at-once approach are two extreme cases of the proposed candidate-based approaches.Experiments on Penn Chinese Treebank 5 and Tsinghua Chinese Treebank show that the generalized candidate-based approach outperforms one-at-a-time approach and even the all-at-once approach.The candidate-based approach is also faster than the time-consuming all-at-once approach.The authors compare three different methods based on sentence,words and character-intervals to generate the candidate set.It turns out that the word-based method has the best performance. 展开更多
关键词 框架 词性标注 汉语分词 表演 中文分词 水煤浆 候选人 日期设置
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铜麦6号苗期耐高铵与耐盐特性的鉴定及TaGS基因的表达模式分析
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作者 张园清 张春丹 +5 位作者 陈斌卿 江娇 郑中尧 郭莹 刘坤祥 徐虹 《麦类作物学报》 CAS CSCD 北大核心 2023年第7期809-818,共10页
为鉴定小麦品种铜麦6号的耐高铵及耐盐特性,对铜麦6号、中国春及抗逆性较强的烟农19、三抗10号、矮优王、烟农21、山农25的发芽势和发芽率进行测定,发现铜麦6号的耐铵指数位列第一,耐盐指数位列第二。以中国春为对照品种,在高铵、高盐... 为鉴定小麦品种铜麦6号的耐高铵及耐盐特性,对铜麦6号、中国春及抗逆性较强的烟农19、三抗10号、矮优王、烟农21、山农25的发芽势和发芽率进行测定,发现铜麦6号的耐铵指数位列第一,耐盐指数位列第二。以中国春为对照品种,在高铵、高盐及其双重胁迫处理下,测定其苗期的叶片鲜重、根鲜重、主根和第一叶叶片长度以及根冠比,发现高铵、高盐及其双重胁迫处理7 d后,铜麦6号的上述指标均不同程度高于中国春(除铜麦6号的根冠比在高盐处理1 d后低于中国春外),说明铜麦6号具有较强的耐高铵和耐高盐特性。进一步采用qRT-PCR检测小麦苗期谷氨酰胺合成酶TaGS基因家族成员(根中TaGS1;1、TaGS1;2和TaGS1;3基因以及叶片中TaGS2基因)的表达模式,发现高铵、高盐及其双重处理均可诱导铜麦6号苗期TaGS基因上调表达,且高盐处理下上调表达更明显,其中除高铵与高盐双重处理7 d后的TaGS1;2基因以及高铵和高盐处理1 d后的TaGS2基因在铜麦6号中的表达量低于中国春外,其他三种处理不同时间点铜麦6号中这两个基因的相对表达量均不同程度高于中国春。这些结果说明,铜麦6号苗期TaGS基因家族与其耐高铵和耐高盐特性相关,其中TaGS1;2和TaGS2基因的贡献较大。 展开更多
关键词 小麦 高铵胁迫 高盐胁迫 tagS基因 表达
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Improved hidden Markov model for speech recognition and POS tagging 被引量:4
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作者 袁里驰 《Journal of Central South University》 SCIE EI CAS 2012年第2期511-516,共6页
In order to overcome defects of the classical hidden Markov model (HMM), Markov family model (MFM), a new statistical model was proposed. Markov family model was applied to speech recognition and natural language proc... In order to overcome defects of the classical hidden Markov model (HMM), Markov family model (MFM), a new statistical model was proposed. Markov family model was applied to speech recognition and natural language processing. The speaker independently continuous speech recognition experiments and the part-of-speech tagging experiments show that Markov family model has higher performance than hidden Markov model. The precision is enhanced from 94.642% to 96.214% in the part-of-speech tagging experiments, and the work rate is reduced by 11.9% in the speech recognition experiments with respect to HMM baseline system. 展开更多
关键词 隐马尔可夫模型 连续语音识别 词性标注 自然语言处理 统计模型 基线系统 HMM 实验
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A New Part-of-Speech Tagging System Based on Closed-words,Word Form and Rules
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作者 吴岩 李修昆 王开铸 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第1期43-45,共3页
A method of part-of-speech tagging of English text based on closed-words, wold-form and rules, its abstract model and formal description of its realizing procedure are presented. Finally, an experimental example is gi... A method of part-of-speech tagging of English text based on closed-words, wold-form and rules, its abstract model and formal description of its realizing procedure are presented. Finally, an experimental example is givento illustrate the application of this method. 展开更多
关键词 Part-of-speech tagging closed-words
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Verification of neutron-induced fission product yields evaluated by a tensor decompsition model in transport-burnup simulations 被引量:2
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作者 Qu‑Fei Song Long Zhu +1 位作者 Hui Guo Jun Su 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第2期190-201,共12页
Neutron-induced fission is an important research object in basic science.Moreover,its product yield data are an indispensable nuclear data basis in nuclear engineering and technology.The fission yield tensor decomposi... Neutron-induced fission is an important research object in basic science.Moreover,its product yield data are an indispensable nuclear data basis in nuclear engineering and technology.The fission yield tensor decomposition(FYTD)model has been developed and used to evaluate the independent fission product yield.In general,fission yield data are verified by the direct comparison of experimental and evaluated data.However,such direct comparison cannot reflect the impact of the evaluated data on application scenarios,such as reactor transport-burnup simulation.Therefore,this study applies the evaluated fission yield data in transport-burnup simulation to verify their accuracy and possibility of application.Herein,the evaluated yield data of235U and239Pu are applied in the transport-burnup simulation of a pressurized water reactor(PWR)and sodium-cooled fast reactor(SFR)for verification.During the reactor operation stage,the errors in pin-cell reactivity caused by the evaluated fission yield do not exceed 500 and 200 pcm for the PWR and SFR,respectively.The errors in decay heat and135Xe and149Sm concentrations during the short-term shutdown of the PWR are all less than 1%;the errors in decay heat and activity of the spent fuel of the PWR and SFR during the temporary storage stage are all less than 2%.For the PWR,the errors in important nuclide concentrations in spent fuel,such as90Sr,137Cs,85Kr,and99Tc,are all less than 6%,and a larger error of 37%is observed on129I.For the SFR,the concentration errors of ten important nuclides in spent fuel are all less than 16%.A comparison of various aspects reveals that the transport-burnup simulation results using the FYTD model evaluation have little difference compared with the reference results using ENDF/B-Ⅷ.0 data.This proves that the evaluation of the FYTD model may have application value in reactor physical analysis. 展开更多
关键词 fission product yield Tensor decomposition Transport-burnup simulation Machine learning
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