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2010年至2024年淮河流域山东省沂源县上消化道癌早诊早治项目情况分析
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作者 李东芝 孙璞 +1 位作者 王俊 丁丽平 《中国肿瘤临床》 北大核心 2025年第19期997-1003,共7页
目的:分析2010年至2024年淮河流域山东省沂源县上消化道癌早诊早治项目的筛查及随访资料,了解筛查结果及变化趋势。方法:数据来源于淮河流域癌症早诊早治项目数据管理系统,山东省沂源县项目点2010年至2024年48205人的筛查数据,采用χ^(2... 目的:分析2010年至2024年淮河流域山东省沂源县上消化道癌早诊早治项目的筛查及随访资料,了解筛查结果及变化趋势。方法:数据来源于淮河流域癌症早诊早治项目数据管理系统,山东省沂源县项目点2010年至2024年48205人的筛查数据,采用χ^(2)检验比较检出率、早诊率和治疗率组间差异;用Joinpoint 5.0.2软件分析变化趋势。结果:2010年至2024年总体高危率为69.58%;男性高危率为68.25%,女性为70.77%,女性高危率高于男性(χ^(2)=35.907,P<0.001)。2010年至2024年人群高危率的变化虽有下降,但差异无统计学意义(AAPP=-3.65%,P=0.514)。从年龄分布来看,高危人群占比最高的年龄组是50~54岁,阳性检出率占比最高的年龄组是65~69岁。总阳性检出率为1.07%、总早诊率为70.46%、总治疗率为95.02%;其中胃癌阳性检出率为0.96%、食管癌为0.11%,胃癌阳性检出率高于食管癌(χ^(2)=177.92,P<0.01)。食管癌早诊率为48.28%、胃癌为73.02%,胃癌早诊率高于食管癌(χ^(2)=7.65,P<0.01)。结论:山东省沂源县胃癌风险率较高,实施胃癌筛查对于疾病防控至关重要,下一步宜加大干预措施,提升项目筛查效果、降低胃癌的发病率和死亡率。 展开更多
关键词 胃癌 食管癌 筛查 淮河流域 随访
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口蹄疫病毒非结构蛋白3AB双抗体夹心ELISA方法的建立 被引量:3
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作者 付元芳 何伟 +10 位作者 孙普 杨林 包慧芳 曹轶梅 白兴文 李平花 李冬 陈应理 刘磊 卢曾军 刘在新 《生物工程学报》 CAS CSCD 北大核心 2020年第11期2357-2366,共10页
抗原纯净度是口蹄疫(Foot-and-mouth disease,FMD)灭活疫苗质量检验的一项重要内容,一般采用疫苗2–3次免疫动物后,检测非结构蛋白(Non-structural protein,NSP)抗体是否阳转,判断疫苗抗原的纯净度。文中旨在建立定量检测FMD灭活疫苗抗... 抗原纯净度是口蹄疫(Foot-and-mouth disease,FMD)灭活疫苗质量检验的一项重要内容,一般采用疫苗2–3次免疫动物后,检测非结构蛋白(Non-structural protein,NSP)抗体是否阳转,判断疫苗抗原的纯净度。文中旨在建立定量检测FMD灭活疫苗抗原中NSP 3AB含量的ELISA方法,为疫苗质量控制提供参考方法。利用口蹄疫病毒(Foot-and-mouth disease virus,FMDV)NSP 3A单克隆抗体和辣根过氧化物酶(Horseradish peroxidase,HRP)标记的3B单克隆抗体,建立定量检测NSP 3AB含量的双抗体夹心ELISA检测方法。采用原核表达并纯化的3AB蛋白作为标准品,标准品系列稀释,绘制标准曲线,以标准品与未加抗原的阴性对照吸光值(OD)的比值大于2.0的标准品最低浓度为最低检测限。标准品浓度介于4.7–600.0 ng/mL之间时,测得的OD值与浓度呈线性相关,回归曲线呈直线,相关系数R2=0.99,确定最低检测限为4.7 ng/mL。检测12份未纯化灭活抗原中3AB蛋白含量介于9.3–200.0 ng/mL之间;而纯化后的病毒抗原中3AB蛋白残留量低于最低检测限;33份来自不同厂家的成品疫苗抗原中9份疫苗抗原3AB蛋白含量在9.0–74.0 ng/mL之间,其余24份疫苗抗原中3AB蛋白残留量低于最低检测限。检测3AB蛋白含量的双抗体夹心ELISA方法能够特异、敏感地检测疫苗抗原中的3AB蛋白含量,为疫苗质量控制与纯净度检验提供了一种可供选择的检测方法。 展开更多
关键词 口蹄疫 非结构蛋白 定量ELISA 疫苗抗原纯净度
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冠醚在多孔材料的研究进展
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作者 孙朴 韩宇霞 吕洁 《分析化学进展》 2025年第2期123-133,共11页
冠醚(Crown Ethers)是一类具有特定环状空腔结构的化合物,从较小的环到较大的多环结构都有(如14-冠-4醚、15-冠-5醚、18-冠-6醚等等),这种特殊的环状结构和尺寸大小赋予了冠醚独特的物理和化学性质,其独特的离子识别能力为高效离子分离... 冠醚(Crown Ethers)是一类具有特定环状空腔结构的化合物,从较小的环到较大的多环结构都有(如14-冠-4醚、15-冠-5醚、18-冠-6醚等等),这种特殊的环状结构和尺寸大小赋予了冠醚独特的物理和化学性质,其独特的离子识别能力为高效离子分离提供了新的解决方案。本文综述了冠醚功能化多孔材料(包括金属有机框架MOFs、共价有机框架COFs、介孔二氧化硅MS)的设计原理、实验结果分析及其在相关领域的应用进展和未来发展方向。 展开更多
关键词 冠醚 多孔材料 MOFS COFs MS 离子分离
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基于Simulink的DPF碳载模型自动标定方法及工程实践 被引量:2
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作者 夏秀娟 张正阳 +2 位作者 pu sun 胡洪祥 John Lee 《柴油机设计与制造》 2021年第3期19-24,共6页
通过MathWorks公司开发(基于Simulink)的模型标定工具箱(MBC),针对大量实车道路试验采集的数据对DPF碳载模型进行自动优化标定。该自动标定方法能减少碳载模型精度对工程师标定经验的依赖。经验证,在输入数据广度足够的前提下,计算输出... 通过MathWorks公司开发(基于Simulink)的模型标定工具箱(MBC),针对大量实车道路试验采集的数据对DPF碳载模型进行自动优化标定。该自动标定方法能减少碳载模型精度对工程师标定经验的依赖。经验证,在输入数据广度足够的前提下,计算输出的碳载模型值与实际称重偏差均值为0.11 g/L,极值0.5 g/L,优于人工离线标定,满足工程应用要求。 展开更多
关键词 DPF碳载模型 离线标定 SIMULINK 标定优化
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The comparison of the efficacy of swine FMD vaccine emulsified with oil adjuvant of ISA 201 VG or ISA 206 VG 被引量:5
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作者 Dong Li Chunxue Zhou +6 位作者 Daliang She Pinghua Li pu sun Xingwen Bai Yingli Chen Baoxia Xie Zaixin Liu 《Journal of Biosciences and Medicines》 2013年第3期22-25,共4页
The Seppic Company developed a new adjuvant Montanide ISA 201 VG, the upgraded version of Montanide ISA 206 VG, which keep the advantage and added some chemical components on the basis of ISA 206 to improve the cellul... The Seppic Company developed a new adjuvant Montanide ISA 201 VG, the upgraded version of Montanide ISA 206 VG, which keep the advantage and added some chemical components on the basis of ISA 206 to improve the cellular responses. The aim of the study is to compare the efficacy of swine FMD (foot-and-mouth) vaccine emulsified with oil adjuvant of ISA 201 or ISA 206 respectively. The pigs were vaccinated with FMD vaccine emulsified with inactive FMD type O antigen and adjuvant ISA 201 or ISA 206 respectively, according to 2.0 ml (1/1 dose), 0.67 ml (1/3 dose), 0.22 ml (1/9 dose) to calculate their PD50. The sera were collected from the vaccination of the day 0, 3, 7, 14, 21, 28 and the ELISA FMD type O antibody were detected. Furthermore, the PD50 were calculated after the pigs were challenged with virulent FMDV type O on 28 days post vaccination. The ELISA antibody titers of 201vaccine were significantly higher than that of 206 (except the third time). The fifty percent of protection dose (PD50) of 201 vaccine (PD50 = 15.59) was higher than that of 206 vaccine (PD50 = 10.05). The above data showed that the efficacy of the FMD vaccine emulsified with ISA 201 was better than which with ISA 206. 展开更多
关键词 SWINE FMD VACCINE ADJUVANT ISA 201 ISA 206 Immune EFFICACY
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A re-assessment of nickel-doping method in iron isotope analysis on rock samples using multi-collector inductively coupled plasma mass spectrometry 被引量:2
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作者 Hongmei Gong Pengyuan Guo +4 位作者 Shuo Chen Meng Duan pu sun Xiaohong Wang Yaoling Niu 《Acta Geochimica》 EI CAS CSCD 2020年第3期355-364,共10页
Element doping has been proved to be a useful method to correct for the mass bias fractionation when analyzing iron isotope compositions.We present a systematic re-assessment on how the doped nickel may affect the iro... Element doping has been proved to be a useful method to correct for the mass bias fractionation when analyzing iron isotope compositions.We present a systematic re-assessment on how the doped nickel may affect the iron isotope analysis in this study by carrying out several experiments.We find three important factors that can affect the analytical results,including the Ni:Fe ratio in the analyte solutions,the match of the Ni:Fe ratio between the unknown sample and standard solutions,and the match of the Fe concentration between the sample and standard solutions.Thus,caution is required when adding Ni to the analyte Fe solutions before analysis.Using our method,theδ56Fe and δ57Fe values of the USGS standards W-2 a,BHVO-2,BCR-2,AGV-2 and GSP-2 are consistent with the recommended literature values,and the long-term(one year) external reproducibility is better than 0.03 and 0.05‰(2 SD) for δ56Fe and δ57Fe,respectively.Therefore,the analytical method established in our laboratory is a method of choice for high quantity Fe isotope data in geological materials. 展开更多
关键词 Fe isotope Ni-doping Stable isotope Precision and accuracy Mass bias correction Pseudohigh mass resolution
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Correction to:A re-assessment of nickel-doping method in iron isotope analysis on rock samples using multi-collector inductively coupled plasma mass spectrometry
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作者 Hongmei Gong Pengyuan Gao +4 位作者 Shuo Chen Meng Duan pu sun Xiaohong Wang Yaoling Niu 《Acta Geochimica》 EI CAS CSCD 2020年第2期280-280,共1页
Fig.7 Iron isotope compositions of various geological samples relative to IRMM-014 analyzed over the period of three months.The gray line represents a linear regression ofδ^56Fe vs.δ^57 Fe with a slope of 1.490±... Fig.7 Iron isotope compositions of various geological samples relative to IRMM-014 analyzed over the period of three months.The gray line represents a linear regression ofδ^56Fe vs.δ^57 Fe with a slope of 1.490±0.015(SE)(R^2=0.9665,N=332).This relationship is statistically consistent with both theoretical predictions of mass-dependent isotope fractionation(slope of 1.475;Young et al.2002)and with previously measured isotopic mass-dependent fractionation trends using Nu Plasma(slope of 1.482;Chen et.al.2017a). 展开更多
关键词 NICKEL DOPING mass
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D/V Meng Xiang is coming to revive the 60-year-old dream of Moho drilling and enter a new phase of international scientific ocean drilling 被引量:1
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作者 Yue Xu Yaoling Niu +7 位作者 Xia Zhang Tienan Chen Tingting Wang Pengyuan Guo pu sun Xiaohong Wang Meng Duan Yanhong Chen 《Science Bulletin》 2025年第12期2023-2024,共2页
“Keeping our original aspiration to realize the dream”!This ancient Chinese saying has inspired many for centuries.To drill the intact ocean crust through the Moho(crust-mantle boundary)into the mantle to reveal the... “Keeping our original aspiration to realize the dream”!This ancient Chinese saying has inspired many for centuries.To drill the intact ocean crust through the Moho(crust-mantle boundary)into the mantle to reveal the mysteries of the deep earth was the very aspiration of the well-known Project Mohole(1957–1966).This 60-year-old dream remains unrealized because of the cost and technological challenges.But this mission is not impossible if we persevere to cope with the challenges through continued scientific collaboration and international cooperation using a state-ofthe-art drilling vessel that is cost effective and technologically capable.The purpose-built D/V Meng Xiang(or“Dream”in Chinese)is the very tool of choice towards realization of this long-awaited dream.Indeed,D/V Meng Xiang carries the dream of global scientists to penetrate the Moho seismic discontinuity(Fig.1). 展开更多
关键词 drill intact ocean crust Mohole Intact ocean crust State art drilling vessel Mantle scientific col Scientific ocean drilling Moho drilling
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一株O型口蹄疫病毒在C57BL/6小鼠和原代细胞的传代及其全序的测定和分析 被引量:3
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作者 龚婷 黄书伦 +10 位作者 查晶晶 孙普 马雪青 白兴文 袁红 曹轶梅 李坤 张婧 卢曾军 刘在新 李平花 《微生物学报》 CAS CSCD 北大核心 2020年第7期1413-1420,共8页
【目的】旨在成功建立FMDVC57BL/6小鼠的实验感染模型。【方法】采用体内和体外循环适应传代的方法,选取一株对C57BL/6小鼠不敏感FMDVO/HK/CHA/99MF4,将其在C57BL/6小鼠(体内)和胎猪肾原代细胞FPK(体外)进行多次循环适应传代。【结果】... 【目的】旨在成功建立FMDVC57BL/6小鼠的实验感染模型。【方法】采用体内和体外循环适应传代的方法,选取一株对C57BL/6小鼠不敏感FMDVO/HK/CHA/99MF4,将其在C57BL/6小鼠(体内)和胎猪肾原代细胞FPK(体外)进行多次循环适应传代。【结果】成功获得一株对C57BL/6小鼠敏感的FMDVO/HK/CHA/99MF4C5株。【结论】本研究成功建立了FMDV突变株感染C57BL/6小鼠的实验动物模型,为未来FMD疫苗效力的评估和致病性相关的研究奠定了基础。 展开更多
关键词 口蹄疫病毒 小鼠 细胞 循环传代 全序的测定与分析
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3A蛋白104–115位氨基酸缺失口蹄疫A型标记病毒的构建 被引量:1
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作者 李平花 马雪青 +5 位作者 袁红 袁子文 孙普 白兴文 卢曾军 刘在新 《微生物学报》 CAS CSCD 北大核心 2019年第5期907-915,共9页
【目的】构建一株含3A非结构蛋白104–115位氨基酸缺失的口蹄疫A型标记病毒,分析其生物学特性和发展标记疫苗的潜力。【方法】采用融合PCR技术,在当前流行毒株A/Sea-97/CHA/2014全长感染性克隆p QAHN中引入3A104–115位氨基酸的缺失,构... 【目的】构建一株含3A非结构蛋白104–115位氨基酸缺失的口蹄疫A型标记病毒,分析其生物学特性和发展标记疫苗的潜力。【方法】采用融合PCR技术,在当前流行毒株A/Sea-97/CHA/2014全长感染性克隆p QAHN中引入3A104–115位氨基酸的缺失,构建全长重组质粒。全长质粒经NotI线化后转染表达T7RNA聚合酶的稳定细胞系,拯救标记病毒。RT-PCR、序列分析、间接免疫荧光和Western blotting鉴定标记病毒。噬斑表型和一步生长曲线分析标记病毒的生物学特性,并用实验室开发的针对3A优势表位(AEKNPLE)的阻断ELISA方法分析其区分亲本和标记病毒感染的动物。【结果】成功拯救到一株含3A 104–115位氨基酸缺失的口蹄疫A型标记病毒,3A表位的缺失没有影响标记病毒的噬斑表型和一步生长曲线。3A单抗阻断ELISA可以明显区分标记病毒和亲本病毒感染的动物。【结论】本研究构建的3A蛋白104–115位氨基酸缺失的标记病毒可以作为发展口蹄疫鉴别诊断疫苗的候选毒株,用于我国未来口蹄疫A型的有效防控。 展开更多
关键词 3A蛋白 104-115位氨基酸缺失 口蹄疫A型 标记病毒 构建
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口蹄疫病毒结构蛋白VP1容忍外源标签的能力
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作者 李平花 马雪青 +5 位作者 寻广谨 白兴文 孙普 袁红 卢曾军 刘在新 《微生物学报》 CAS CSCD 北大核心 2017年第5期659-666,共8页
【目的】利用口蹄疫病毒的反向遗传操作技术,构建含不同外源标签口蹄疫病毒的全长克隆,鉴定口蹄疫病毒结构蛋白VP1容忍不同外源标签的能力。【方法】通过融合PCR技术,在FMDV O/HN/93全长感染性克隆的VP1 G-H环分别引入V5、TC12、KT3、3F... 【目的】利用口蹄疫病毒的反向遗传操作技术,构建含不同外源标签口蹄疫病毒的全长克隆,鉴定口蹄疫病毒结构蛋白VP1容忍不同外源标签的能力。【方法】通过融合PCR技术,在FMDV O/HN/93全长感染性克隆的VP1 G-H环分别引入V5、TC12、KT3、3FLAG外源标签,构建全长质粒。全长质粒经Not I线化后转染表达T7 RNA聚合酶的稳定细胞,拯救重组病毒。RT-PCR、序列测定、间接免疫荧光鉴定病毒,噬斑和一步生长曲线分析重组病毒的生物学特性。【结果】成功拯救到表达V5或KT3表位标签的重组病毒,未能拯救到表达TC12或3×FLAG的重组病毒。V5和KT3表位标签的插入均影响了口蹄疫病毒的复制能力。【结论】重组口蹄疫病毒的成功拯救为未来标记疫苗以及口蹄疫病毒作为表达载体等的研究奠定了基础。 展开更多
关键词 口蹄疫病毒 结构蛋白 外源标签
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VP3 G–H环中氨基酸突变对O型口蹄疫病毒生物学特性的影响 被引量:2
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作者 陈冬冬 白兴文 +12 位作者 宫晓华 包慧芳 李平花 李冬 付元芳 白启峰 袁红 孙普 马雪青 曹轶梅 陈应理 卢曾军 刘在新 《微生物学报》 CAS CSCD 北大核心 2019年第7期1285-1294,共10页
【目的】为了研究O型口蹄疫病毒VP3 G–H环中氨基酸突变对其生物学特性的影响。【方法】借助口蹄疫病毒反向遗传操作技术平台拯救出2株定点突变体rHNV3174Y和rHND3173N+V3174E+N3179C。进行蚀斑形成试验、一步生长曲线的绘制、TCID50和L... 【目的】为了研究O型口蹄疫病毒VP3 G–H环中氨基酸突变对其生物学特性的影响。【方法】借助口蹄疫病毒反向遗传操作技术平台拯救出2株定点突变体rHNV3174Y和rHND3173N+V3174E+N3179C。进行蚀斑形成试验、一步生长曲线的绘制、TCID50和LD50的测定、间接免疫荧光与激光共聚焦显微镜检测。【结果】结果显示,与骨架病毒rHN相比,虽然rHNV3174Y和rHND3173N+V3174E+N3179C对BHK-21细胞的感染性及其蚀斑表型和复制动力学无显著性差异;但rHNV3174Y和rHND3173N+V3174E+N3179C对乳鼠的致病力明显减弱,且均获得了小窝蛋白介导侵染CHO-K1细胞的能力。【结论】VP3上第3174位特征性氨基酸突变影响O型口蹄疫病毒感染宿主细胞的毒力及其内吞作用路径,这有助于我们认知VP3 G-H环在口蹄疫病毒粒子立体空间构象中潜在的作用。 展开更多
关键词 口蹄疫病毒 VP3 G-H环 定点突变体 生物学特性 内吞作用
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Exotic origin of the Chinese continental shelf: new insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic 被引量:35
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作者 Yaoling Niu Yi Liu +15 位作者 Qiqi Xue Fengli Shao Shuo Chen Meng Duan Pengyuan Guo Hongmei Gong Yan Hu Zhenxing Hu Juanjuan Kong Jiyong Li Jinju Liu pu sun Wenli sun Lei Ye Yuanyuan Xiao Yu Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2015年第18期1598-1616,共19页
The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern c... The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern continental China in space and time has led us to an interesting conclusion: The basement of the continental shelf beneath East and South China Seas may actually be of exotic origin geologically unrelated to the continental lithosphere of eastern China. By accepting the notion that the Jurassic- Cretaceous granitoids in the region are genetically associated with western Pacific subduction and the concept that subduction may cease to continue only if the trench is being jammed, then the termination of the granitoid magmatism throughout the vast region at -88±2 Ma manifests the likelihood of "sudden", or shortly beforehand (- 100 Ma), trench jam of the Mesozoic western Pacific subduction. Trench jam happens if the incoming "plate" or portion of the plate contains a sizeable mass that is too buoyant to subduct. The best candidate for such a buoyant and unsubductable mass is either an oceanic plateau or a micro-continent. We hypothesize that the basement of the Chinese continental shelf represents such an exotic, buoyant and unsubductable mass, rather than seaward extension of the continental lithosphere of eastern China. The locus of the jammed trench (i.e., the suture) is predictably located on the shelf in the vicinity of, and parallel to, the arc-curved coastal line of the southeast continental China. It is not straightforward to locate the locus in the northern section of the East China Sea shelf because of the more recent (〈20 Ma) tectonic re-organization associated with the opening of the Sea of Japan. We predict that the trench jam at - 100 Ma led to the re-orientation of the Pacific plate motion in the course of NNW direction as inferred from the age-progressive Emperor Seamount Chain of Hawaiian hotspot origin (its oldest unsubdued Meiji and Detroit seamounts are -82 Ma), making the boundary between the Pacific plate and the newly accreted plate of eastern Asia transform fault at the location east of the continental shelf of exotic origin. This explains the apparent-40 Myr magmatic gap from - 88 to - 50 Ma prior to present-day western Pacific subduction initiation. We propose that basement penetration drilling on well-chosen sites is needed to test the hypothesis in order to reveal the true nature of the Chinese continental shelf basement. This testing becomes critical and cannot longer be neglected in order to genuinely understand the tectonic evolution of the western Pacific and its effect on the geology of eastern China since the Mesozoic, including the cratonic lithosphere thinning, related magmatism/mineralization, and the mechanism of the subsequent South China Sea opening, while also offering novel perspectives on aspects of the plate tectonics theory. We also suggest the importance of future plate tectonic reconstruction of the western Pacific to consider the nature and histories of the Chinese continental shelf of exotic origin as well as the probable transform plate boundary from - 100 to -50 Ma. Effort is needed to reveal the true nature and origin of the - 88 ± 2 Ma granitic gneisses in Taiwan and the 110-88 Ma granitoids on the Hainan Island. 展开更多
关键词 Mesozoic granitoids in eastern ChinaExotic origin of Chinese continental shelf Trenchjam Transform plate boundary Basal hydrationweakening Lithosphere thinning Cratondestruction Mantle hydrous melting Crustalmelting Plate tectonics South China Sea
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Simple and cost-effective methods for precise analysis of trace element abundances in geological materials with ICP-MS 被引量:23
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作者 Shuo Chen Xiaohong Wang +7 位作者 Yaoling Niu pu sun Meng Duan Yuanyuan Xiao Pengyuan Guo Hongmei Gong Guodong Wang Qiqi Xue 《Science Bulletin》 SCIE EI CAS CSCD 2017年第4期277-289,共13页
Inductively coupled plasma mass spectrometry (ICP-MS) is the most commonly used technique to deter- mine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion... Inductively coupled plasma mass spectrometry (ICP-MS) is the most commonly used technique to deter- mine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion, isobaric interferences and instrumental drift remain obvious problems that must be overcome in order to obtain precise and accurate results, For this reason, we have done many experi- ments and developed a set of simple, cost-effective and practical methods widely applicable for precise and rapid determination of trace element abundances in geological materials using ICP-MS. Commonly used high-pressure digestion technique is indeed effective in decomposing refractory phases, but this inevitably produces fluoride complexes that create new problems. We demonstrate that the fluoride complexes formed during high-pressure digestion can be readily re-dissolved using high-pressure vessel at 190 ℃ for only 2 h for 50 mg sample. In the case of isobaric interferences, although oxide (e.g., MO^+/M^+) and hydroxide (e.g., MO^+/M^+) productivity is variable between runs, the (MO^+/M^+)/(CeO^+/Ce^+) and (MOH^+/M^+)/(CeO^+/Ce^+) ratios remain constant, making isobaric interference correction for all other elements of interest straightforward, for which we provide an easy-to-use off-line procedure. We also show that mass-time-intensity drift curve is smooth as recognized previously, for which the correction can be readily done by analyzing a quality-control (QC) solution and using off-line Excel VBA procedure without internal standards. With these methods, we can produce data in reasonable agreement with rec- ommended values of international rock reference standards with a relative error of 〈8% and precision generally better than 5%. Importantly, compared to the widely used analytical practice, we can effectively save 〉60% of time (e.g., 〈24 h vs. 〉60 h). 展开更多
关键词 Inductively coupled plasma mass spectrometry High-pressure digestion Oxide and hydroxide interferences Instrumental drift Correction methods Trace elements
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VenomAttack: automated and adaptive activity hijacking in Android
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作者 pu sun Sen CHEN +3 位作者 Lingling FAN Pengfei GAO Fu SONG Min YANG 《Frontiers of Computer Science》 SCIE EI CSCD 2023年第1期187-204,共18页
Activity hijacking is one of the most powerful attacks in Android. Though promising, all the prior activity hijacking attacks suffer from some limitations and have limited attack capabilities. They no longer pose secu... Activity hijacking is one of the most powerful attacks in Android. Though promising, all the prior activity hijacking attacks suffer from some limitations and have limited attack capabilities. They no longer pose security threats in recent Android due to the presence of effective defense mechanisms. In this work, we propose the first automated and adaptive activity hijacking attack, named VenomAttack, enabling a spectrum of customized attacks (e.g., phishing, spoofing, and DoS) on a large scale in recent Android, even the state-of-the-art defense mechanisms are deployed. Specifically, we propose to use hotpatch techniques to identify vulnerable devices and update attack payload without re-installation and re-distribution, hence bypassing offline detection. We present a newly-discovered flaw in Android and a bug in derivatives of Android, each of which allows us to check if a target app is running in the background or not, by which we can determine the right attack timing via a designed transparent activity. We also propose an automated fake activity generation approach, allowing large-scale attacks. Requiring only the common permission INTERNET, we can hijack activities at the right timing without destroying the GUI integrity of the foreground app. We conduct proof-of-concept attacks, showing that VenomAttack poses severe security risks on recent Android versions. The user study demonstrates the effectiveness of VenomAttack in real-world scenarios, achieving a high success rate (95%) without users’ awareness. That would call more attention to the stakeholders like Google. 展开更多
关键词 ANDROID activity hijacking Android security mobile security
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