The Neoproterozoic Jiangnan orogen plays an important role in the study of the Precambrian tectonic evolution of South China. The tectonic nature of the Neoproterozoic sedimentary basins is still controversial, due to...The Neoproterozoic Jiangnan orogen plays an important role in the study of the Precambrian tectonic evolution of South China. The tectonic nature of the Neoproterozoic sedimentary basins is still controversial, due to poor understanding of the sedimentary sequences and the lack of geochronological data. Here, we present sedimentological, provenance and geochronological data from the Heshangzhen Group in the eastern Jiangnan orogen. Sedimentological analysis shows that the Luojiamen Formation was deposited in a submarine fan, and the overlying Hongchicun Formation was deposited in front of a fan delta. The youngest detrital zircons constrain the lower Luojiamen and Hongchicun formations with ages of 827.3 ± 8.4 Ma and 825 ± 12 Ma, respectively. The sandstones of the Luojiamen Formation are characterized by a large number of intermediate to felsic volcanic grains, suggesting a volcanic arc source. In contrast, quartz and sedimentary lithic grains increase in the Hongchicun Formation, showing a new input from a collisional orogenic source. Detrital zircon from six sandstone samples in the Luojiamen and Hongchicun formations yield similar age spectra of 930–820 Ma with a peak at ca. 845–860 Ma, with one main cluster at 930–820 Ma. Detrital zircons of 930–845 Ma show a positive value of εHf(t)(+2.4 to +11, mean +7.6), which is similar to the volcanic arc of the nearby Shuangxiwu Group. There are a minor group of zircons with U-Pb ages ranging from 820 Ma to 845 Ma from the middle part of the Luojiamen Formation and Hongchicun Formation, with εHf(t) values between-20 to +2.4, which are consistent with the characteristics of the Shuangqiaoshan Group. within light of the bidirectional paleocurrents in the Luojiamen Formation, it is speculated that the zircons of 820–845 Ma were recycled from the Shuangqiaoshan Group, which is derived from a continental arc to the northwest. Our data suggests that the Luojiamen Formation was formed in an inter-arc basin, while the Hongchicun Formation was formed in an accretionary wedge-top basin. When juxtaposed with the conglomeratic characteristics at the bottom of the Luojiamen Formation, it is believed that the unconformity represented by the ‘Shen Gong Movement' reflects the rapid erosion and accumulation process of island arc volcanic material. The disconformity between the Luojiamen and Hongchicun formations is the imprint of transition from inter-arc basin to accretionary wedge-top basin,which represents the collision between the Shuangxiwu arc and the Yangtze Plate.展开更多
液滴的瞬态行为对强化水平管降膜吸收CO_(2)装置的性能至关重要。基于VOF(volume of fluid)方法建立了滴状流降膜吸收CO_(2)的二维模型,引入液滴下坠长度与无量纲时间来分析滴状流降膜吸收CO_(2)过程中的液滴脉动与管间距和雷诺数Re的...液滴的瞬态行为对强化水平管降膜吸收CO_(2)装置的性能至关重要。基于VOF(volume of fluid)方法建立了滴状流降膜吸收CO_(2)的二维模型,引入液滴下坠长度与无量纲时间来分析滴状流降膜吸收CO_(2)过程中的液滴脉动与管间距和雷诺数Re的关系。结果表明:液体在换热管下侧堆积直至形成液滴的过程中,受到重力、表面张力与惯性的相互作用,液滴的移动方向出现了多次反转;液滴脉动过程中,由于摩擦阻力的存在,随着无量纲时间的增加,液滴脉动幅度逐渐减小;由于管间距的增加提高了液滴在换热管底部交汇时的动能,导致随着管间距的增加,液滴的脉动次数与脉动幅度逐渐增加;在Re不断增加的情况下,液滴滴落速度的减小导致液滴的脉动次数与幅度也逐渐减小。展开更多
目的 观察长链非编码RNA CTC-459F4.3在肝癌组织和肝癌细胞中的表达,探索过表达CTC-459F4.3对肝癌细胞增殖和迁移的影响及作用机制。方法 qPCR检测CTC-459F4.3在28例肝癌组织和肝癌细胞株(Huh7、SMMC-7721、MHCC-97H和BEL-7404)中的表...目的 观察长链非编码RNA CTC-459F4.3在肝癌组织和肝癌细胞中的表达,探索过表达CTC-459F4.3对肝癌细胞增殖和迁移的影响及作用机制。方法 qPCR检测CTC-459F4.3在28例肝癌组织和肝癌细胞株(Huh7、SMMC-7721、MHCC-97H和BEL-7404)中的表达。选择CTC-459F4.3表达最低的肝癌细胞株,分为阴性对照组(转染阴性质粒)和CTC-459F4.3组(转染CTC-459F4.3质粒)。MTT法和Transwell迁移实验分别检测过表达CTC-459F4.3对细胞增殖能力和迁移能力的影响。免疫组化检测肝癌组织中羧基末端区域小磷酸化酶样蛋白(CTDSPL)的表达。qPCR和Western blot分别检测过表达CTC-459F4.3对CTDSPL基因表达的影响。结果 与癌旁组织相比,CTC-459F4.3在肝癌组织呈低表达( P <0.01)。与人正常肝细胞相比,CTC-459F4.3在肝癌细胞株呈低表达( P <0.05),CTC-459F4.3在SMMC-7721细胞中的表达最低( P <0.01)。与阴性对照组相比,CTC-459F4.3组SMMC-7721细胞的增殖能力明显下降( P <0.05),细胞迁移能力明显降低( P <0.05)。与癌旁组织相比,CTDSPL蛋白在肝癌组织中的表达明显降低。与阴性对照组相比,CTC-459F4.3组SMMC-7721细胞中CTC-459F4.3表达明显增加( P <0.01)。结论 CTC-459F4.3在肝癌组织和肝癌细胞中呈低表达,过表达CTC-459F4.3可显著抑制肝癌SMMC-7721细胞的增殖能力和迁移能力,其作用机制可能是上调CTDSPL基因的表达。展开更多
江苏如东县洋口港地区普遍发育末次冰盛期(MIS 2)"第一硬粘土层"。全新世早期,该区暴露侵蚀,仅局部地区发育潮汐水道。全新世中期(7 000 a B.P.)以来,在最大海侵作用影响下,研究区大部分地区以潮坪沉积为主;高海平面时期(5 22...江苏如东县洋口港地区普遍发育末次冰盛期(MIS 2)"第一硬粘土层"。全新世早期,该区暴露侵蚀,仅局部地区发育潮汐水道。全新世中期(7 000 a B.P.)以来,在最大海侵作用影响下,研究区大部分地区以潮坪沉积为主;高海平面时期(5 220 a B.P.),研究区大部分地区处于水下沉积环境;随着海平面下降,北部地区发育古潮成砂体,属于滨海潮坪—潮成砂脊沉积体系。根据地层沉积特征,识别出4期埋藏古潮成砂脊。地层AMS14C年龄表明,4期砂脊是依次在5 220~1 000 a B.P.沉积形成的,反映了潮汐动力作用下古潮成砂脊的动态演化过程。展开更多
基金supported by the Geological Survey Project of the Chinese Geological Survey(DD20190043,DD20160038)。
文摘The Neoproterozoic Jiangnan orogen plays an important role in the study of the Precambrian tectonic evolution of South China. The tectonic nature of the Neoproterozoic sedimentary basins is still controversial, due to poor understanding of the sedimentary sequences and the lack of geochronological data. Here, we present sedimentological, provenance and geochronological data from the Heshangzhen Group in the eastern Jiangnan orogen. Sedimentological analysis shows that the Luojiamen Formation was deposited in a submarine fan, and the overlying Hongchicun Formation was deposited in front of a fan delta. The youngest detrital zircons constrain the lower Luojiamen and Hongchicun formations with ages of 827.3 ± 8.4 Ma and 825 ± 12 Ma, respectively. The sandstones of the Luojiamen Formation are characterized by a large number of intermediate to felsic volcanic grains, suggesting a volcanic arc source. In contrast, quartz and sedimentary lithic grains increase in the Hongchicun Formation, showing a new input from a collisional orogenic source. Detrital zircon from six sandstone samples in the Luojiamen and Hongchicun formations yield similar age spectra of 930–820 Ma with a peak at ca. 845–860 Ma, with one main cluster at 930–820 Ma. Detrital zircons of 930–845 Ma show a positive value of εHf(t)(+2.4 to +11, mean +7.6), which is similar to the volcanic arc of the nearby Shuangxiwu Group. There are a minor group of zircons with U-Pb ages ranging from 820 Ma to 845 Ma from the middle part of the Luojiamen Formation and Hongchicun Formation, with εHf(t) values between-20 to +2.4, which are consistent with the characteristics of the Shuangqiaoshan Group. within light of the bidirectional paleocurrents in the Luojiamen Formation, it is speculated that the zircons of 820–845 Ma were recycled from the Shuangqiaoshan Group, which is derived from a continental arc to the northwest. Our data suggests that the Luojiamen Formation was formed in an inter-arc basin, while the Hongchicun Formation was formed in an accretionary wedge-top basin. When juxtaposed with the conglomeratic characteristics at the bottom of the Luojiamen Formation, it is believed that the unconformity represented by the ‘Shen Gong Movement' reflects the rapid erosion and accumulation process of island arc volcanic material. The disconformity between the Luojiamen and Hongchicun formations is the imprint of transition from inter-arc basin to accretionary wedge-top basin,which represents the collision between the Shuangxiwu arc and the Yangtze Plate.
文摘液滴的瞬态行为对强化水平管降膜吸收CO_(2)装置的性能至关重要。基于VOF(volume of fluid)方法建立了滴状流降膜吸收CO_(2)的二维模型,引入液滴下坠长度与无量纲时间来分析滴状流降膜吸收CO_(2)过程中的液滴脉动与管间距和雷诺数Re的关系。结果表明:液体在换热管下侧堆积直至形成液滴的过程中,受到重力、表面张力与惯性的相互作用,液滴的移动方向出现了多次反转;液滴脉动过程中,由于摩擦阻力的存在,随着无量纲时间的增加,液滴脉动幅度逐渐减小;由于管间距的增加提高了液滴在换热管底部交汇时的动能,导致随着管间距的增加,液滴的脉动次数与脉动幅度逐渐增加;在Re不断增加的情况下,液滴滴落速度的减小导致液滴的脉动次数与幅度也逐渐减小。
文摘目的 观察长链非编码RNA CTC-459F4.3在肝癌组织和肝癌细胞中的表达,探索过表达CTC-459F4.3对肝癌细胞增殖和迁移的影响及作用机制。方法 qPCR检测CTC-459F4.3在28例肝癌组织和肝癌细胞株(Huh7、SMMC-7721、MHCC-97H和BEL-7404)中的表达。选择CTC-459F4.3表达最低的肝癌细胞株,分为阴性对照组(转染阴性质粒)和CTC-459F4.3组(转染CTC-459F4.3质粒)。MTT法和Transwell迁移实验分别检测过表达CTC-459F4.3对细胞增殖能力和迁移能力的影响。免疫组化检测肝癌组织中羧基末端区域小磷酸化酶样蛋白(CTDSPL)的表达。qPCR和Western blot分别检测过表达CTC-459F4.3对CTDSPL基因表达的影响。结果 与癌旁组织相比,CTC-459F4.3在肝癌组织呈低表达( P <0.01)。与人正常肝细胞相比,CTC-459F4.3在肝癌细胞株呈低表达( P <0.05),CTC-459F4.3在SMMC-7721细胞中的表达最低( P <0.01)。与阴性对照组相比,CTC-459F4.3组SMMC-7721细胞的增殖能力明显下降( P <0.05),细胞迁移能力明显降低( P <0.05)。与癌旁组织相比,CTDSPL蛋白在肝癌组织中的表达明显降低。与阴性对照组相比,CTC-459F4.3组SMMC-7721细胞中CTC-459F4.3表达明显增加( P <0.01)。结论 CTC-459F4.3在肝癌组织和肝癌细胞中呈低表达,过表达CTC-459F4.3可显著抑制肝癌SMMC-7721细胞的增殖能力和迁移能力,其作用机制可能是上调CTDSPL基因的表达。
文摘江苏如东县洋口港地区普遍发育末次冰盛期(MIS 2)"第一硬粘土层"。全新世早期,该区暴露侵蚀,仅局部地区发育潮汐水道。全新世中期(7 000 a B.P.)以来,在最大海侵作用影响下,研究区大部分地区以潮坪沉积为主;高海平面时期(5 220 a B.P.),研究区大部分地区处于水下沉积环境;随着海平面下降,北部地区发育古潮成砂体,属于滨海潮坪—潮成砂脊沉积体系。根据地层沉积特征,识别出4期埋藏古潮成砂脊。地层AMS14C年龄表明,4期砂脊是依次在5 220~1 000 a B.P.沉积形成的,反映了潮汐动力作用下古潮成砂脊的动态演化过程。