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Correlation between cerebral cortex changes and clinical features in patients with neuromyelitis optica spectrum disorder with normal-appearing brain tissue:a case-control study 被引量:1
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作者 Chuxin Huang Yanyu Li +5 位作者 yanjing chen Xuan Liao Huiting Zhang Zhiyuan Wang Jun Liu Wei Lu 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第11期2520-2525,共6页
Neuro myelitis optica spectrum disorder(NMOSD) is an inflammatory demyelinating disease of the central nervous system.However,whether and how cortical changes occur in NMOSD with normal-appearing brain tissue,or wheth... Neuro myelitis optica spectrum disorder(NMOSD) is an inflammatory demyelinating disease of the central nervous system.However,whether and how cortical changes occur in NMOSD with normal-appearing brain tissue,or whether any cortical changes correlate with clinical chara cteristics,is not completely clear.The current study recruited 43 patients with NMOSD who had normal-appearing brain tissue and 45 healthy controls matched for age,sex,and educational background from December 2020 to February 2022.A surface-based morphological analysis of high-resolution T1-weighted structural magnetic resonance images was used to calculate the cortical thickness,sulcal depth,and gyrification index.Analysis showed that cortical thickness in the bilate ral rostral middle frontal gyrus and left superior frontal gyrus was lower in the patients with NMOSD than in the control participants.Subgroup analysis of the patients with NMOSD indicated that compared with those who did not have any optic neuritis episodes,those who did have such episodes exhibited noticeably thinner cortex in the bilateral cuneus,superior parietal co rtex,and pericalcarine co rtex.Correlation analysis indicated that co rtical thickness in the bilateral rostral middle frontal gyrus was positively correlated with scores on the Digit Symbol Substitution Test and negatively correlated with scores on the Trail Making Test and the Expanded Disability Status Scale.These results are evidence that cortical thinning of the bilateral regional frontal cortex occurs in patients with NMOSD who have normal-appearing brain tissue,and that the degree of thinning is correlated with clinical disability and cognitive function.These findings will help im prove our understanding of the imaging chara cteristics in NMOSD and their potential clinical significance. 展开更多
关键词 cognitive function cortical thickness Expanded Disability Status Scale GYRIFICATION magnetic resonance imaging neuromyelitis optica spectrum disorder normal-appearing brain tissue rostral middle frontal gyrus sulcal depth superior frontal gyrus
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Global glaciations and atmospheric change at ca.2.3 Ga 被引量:14
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作者 Haoshu Tang yanjing chen 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第5期583-596,共14页
岩石层位学的编译和 geochronological 数据为 Palaeoproterozoic 冰川的忍受 diamictite 继任获得了的这份报纸,并且从而提供卓见进理解引起 Huronian 冻结成冰事件的地质的进程。为这个冻结成冰事件的外观的证据的多数能与 Kenorland... 岩石层位学的编译和 geochronological 数据为 Palaeoproterozoic 冰川的忍受 diamictite 继任获得了的这份报纸,并且从而提供卓见进理解引起 Huronian 冻结成冰事件的地质的进程。为这个冻结成冰事件的外观的证据的多数能与 Kenorland supercontinent 决裂有关,对 biogeochemical 的重要大气的变化,以及花蕾联盟氧的光合作用。在这份报纸, Huronian 冻结成冰事件被抑制在 2.292.25 Ga 期间同时地发生了,由包括 pre-2.3 Ga 水圈氧化和 post-2.3 Ga 空气氧化的大氧化事件特征的戏剧的环境变化伴随了。 展开更多
关键词 大气变化 冰期事件 冰川 生物地球化学 环境变化特征 超大陆裂解 古元古代 地质过程
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The Geology and Tectonic Settings of China's Mineral Deposits by Franco Pirajno 被引量:5
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作者 yanjing chen 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第4期477-477,共1页
Springer Verlag,Berlin,2013,679 pp.ISBN:978-94-007-4443-1 China is the third largest country in the world,with a land area of about 9.6 million km2.It is endowed with abundant mineral resources,and the metal mining ac... Springer Verlag,Berlin,2013,679 pp.ISBN:978-94-007-4443-1 China is the third largest country in the world,with a land area of about 9.6 million km2.It is endowed with abundant mineral resources,and the metal mining activity can be traced back to ca. 8000 years ago.However,due to language barrier,little has been known about the geology and tectonics to the outside world 展开更多
关键词 矿床地质构造 中国 ISBN 出版社 设置 柏林 土地面积 矿产资源
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Besshi-type mineral systems in the Palaeoproterozoic Bryah Rift-Basin, Capricorn Orogen, Western Australia: Implications for tectonic setting and geodynamic evolution 被引量:2
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作者 Franco Pirajno yanjing chen +2 位作者 Nuo Li Chao Li Limin Zhou 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第3期345-357,共13页
In this contribution we use VMS mineral systems in the Bryah rift-basin to constrain the tectonic setting of the widespread mafic and ultramafic magmatism that characterises the rift-basin in question.Two distinct,but... In this contribution we use VMS mineral systems in the Bryah rift-basin to constrain the tectonic setting of the widespread mafic and ultramafic magmatism that characterises the rift-basin in question.Two distinct,but temporally closely associated,lithostratigraphic sequences,Narracoota and Karalundi Formations,are discussed.The Karalundi Formation is the main host of VMS mineral systems in the region.The Karalundi Formation consists of turbiditic and immature clastic sediments,which are locally intercalated with basaltic hyaloclastites,dolerites and banded jaspilites.We propose that the basaltic hyaloclastites,dolerites and elastics and jaspilites rocks,form a distinct unit of the Karalundi Formation,named Noonyereena Member.The VMS mineral systems occur near the north-east trendingJenkin Fault and comprise the giant and world-class DeCrussa and the Red Bore deposits.The nature of these deposits and their intimate association with terrigenous clastic rocks and dominantly marine mafic volcanic and subvolcanic rocks,as well as the common development of peperitic margins,are considered indicative of a Besshi-type environment,similar to that of present-day Gulf of California.Our Re-Os age data from a primary pyrite yielded a mean model age of 2012 ± 48 Ma,which coincides(within error) with recent published Re-Os data(Hawke et al.,2015) and confirms the timing of the proposed geodynamic evolution.We propose a geodynamic model that attempts to explain the presence of the Narracoota and Karalundi Formations as the result of mantle plume activity,which began with early uplift of continental crust with intraplate volcanism,followed by early stages of rifting with the deposition of the Karalundi Formation(and Noonyereena Member),which led to the formation of Besshi-type VMS deposits.With on-going mantle plume activity and early stages of continental separation,an oceanic plateau was formed and is now represented by mafic-ultramafic rocks of the Narracoota Formation. 展开更多
关键词 地球动力学演化 裂谷盆地 西澳大利亚 镁铁质-超镁铁质岩 系统 古元古代 矿物 构造
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Tourmaline geochemistry and boron isotopic variations as a guide to fluid evolution in the Qiman Tagh W-Sn belt, East Kunlun, China 被引量:1
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作者 Zhen Zheng yanjing chen +3 位作者 Xiaohua Deng Suwei Yue Hongjin chen Qingfei Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2019年第2期569-580,共12页
The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen, NW China, and is associated with early Paleozoic monzogranites, tourmaline is present throughout this belt. In this paper we report c... The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen, NW China, and is associated with early Paleozoic monzogranites, tourmaline is present throughout this belt. In this paper we report chemical and boron isotopic compositions of tourmaline from wall rocks, monzogranites, and quartz veins within the belt, for studying the evolution of ore-forming fluids. Tourmaline crystals hosted in the monzogranite and wall rocks belong to the alkali group, while those hosted in quartz veins belong to both the alkali and X-site vacancy groups. Tourmaline in the walk rocks lies within the schorl-dravite series and becomes increasingly schorlitic in the monzogranite and quartz veins. Detrital tourmaline in the wall rocks is commonly both optically and chemically zoned,with cores being enriched in Mg compared with the rims. In the Al-Fe-Mg and Ca-Fe-Mg diagrams,tourmaline from the wall rocks plots in the fields of Al-saturated and Ca-poor metapelite, and extends into the field of Li-poor granites, while those from the monzogranite and quartz veins lie within the field of Li-poor granites. Compositional substitution is best represented by the MgFe_(-1), Al(NaR)_(-1), and AlO(Fe(OH))_(-1) exchange vectors. A wider range of δ^(11)B values from -11.1‰ to -7.1‰ is observed in the wall-rock tourmaline crystals, the B isotopic values combining with elemental diagrams indicate a source of metasediments without marine evaporates for the wall rocks in the Qiman Tagh belt. The δ^(11)B values of monzogranite-hosted tourmaline range from -10.7‰ and-9.2‰, corresponding to the continental crust sediments, and indicate a possible connection between the wall rocks and the monzogranite. The overlap in δ^(11)B values between wall rocks and monzogranite implies that a transfer of δ^(11)B values by anataxis with little isotopic fractionation between tourmaline and melts. Tourmaline crystals from quartz veins have δ^(11)B values between -11.0‰ and-9.6‰, combining with the elemental diagrams and geological features, thus indicating a common granite-derived source for the quartz veins and little B isotopic fractionation occurred. Tourmalinite in the wall rocks was formed by metasomatism by a granite-derived hydrothermal fluid, as confirmed by the compositional and geological features.Therefore, we propose a single B-rich sedimentary source in the Qiman Tagh belt, and little boron isotopic fractionation occurred during systematic fluid evolution from the wall rocks, through monzogranite, to quartz veins and tourmalinite. 展开更多
关键词 TOURMALINE Chemical composition BORON isotope Qiman Tagh W-Sn BELT Fluid evolution
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Daily ETC Traffic Flow Time Series Prediction Based on k-NN and BP Neural Network
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作者 yanjing chen Yawei Zhao Peng Yan 《国际计算机前沿大会会议论文集》 2016年第2期40-41,共2页
Daily Electronic Toll Collection(ETC)traffic flow prediction is one of the fundamental processes in ETC management.The precise prediction of traffic flow provides instructions for transportation hub management solutio... Daily Electronic Toll Collection(ETC)traffic flow prediction is one of the fundamental processes in ETC management.The precise prediction of traffic flow provides instructions for transportation hub management solution planning and ETC lane construction.At present,some of studies are proposed in forecasting traffic flow.However,most studies of model presentation are in the form of mathematical expressions,and it is difficult to describe the trend accurately.Therefore,an ETC traffic flow prediction model based on k nearest neighbor searching(k-NN)and Back Propagation(BP)neural network is proposed,which takes the effect of external factors like holiday,the free of highway and weather etc.into consideration.The traffic flow data of highway ETC lane somewhere is used for prediction.The prediction results indicate that the total average absolute relative error is 5.01%.The accuracy suggests its advantage in traffic flow prediction and on site application. 展开更多
关键词 ETC TRAFFIC flow prediction Time series K-NN BP NEURAL network
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Hydrothermal ore deposits in collisional orogens 被引量:26
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作者 Yongfei Zheng Jingwen Mao +3 位作者 yanjing chen Weidong Sun Pei Ni Xiaoyong Yang 《Science Bulletin》 SCIE EI CSCD 2019年第3期205-212,共8页
Hydrothermal ore deposits at convergent plate boundaries represent extraordinary metal enrichment in the continental crust. They are generally associated with felsic magmatism in extensional settings at high thermal g... Hydrothermal ore deposits at convergent plate boundaries represent extraordinary metal enrichment in the continental crust. They are generally associated with felsic magmatism in extensional settings at high thermal gradients. Although their formation is common during accretionary orogeny, more and more ore deposits have been discovered recently in the collisional orogens of China. Because collisional orogeny was operated in a compressional regime at low thermal gradients, it is not favorable for mobilization of ore-forming elements and thus for the production of hydrothermal ore deposits. Nevertheless, continental collision is generally preceded by oceanic subduction, which enables the preliminary enrichment of ore-forming elements in the mantle wedge due to chemical metasomatism by subducting slab-derived fluids. This gave rise to metal pre-enriched domains in the overriding lithosphere, which may be reactivated by extensional tectonism for hydrothermal mineralization either immediately during accretionary orogeny or at a later time during and after collisional orogeny. It is these tectonic processes that have resulted in the progressive enrichment of ore-forming elements through the geochemical differentiation of the subducting oceanic crust, the metasomatic mantle domains and the mafic juvenile crust, respectively, at different depths. Finally, the reactivation of metal pre-enriched domains by continental rifting in the orogenic lithosphere is the key to the metallogenesis of collisional orogens. 展开更多
关键词 Ore deposits HYDROTHERMAL fluid ACCRETIONARY OROGEN COLLISIONAL OROGEN RIFTING OROGEN Tectonic REACTIVATION
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Progress and records in the study of endogenetic mineralization during collisional orogenesis 被引量:13
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作者 yanjing chen Huayong chen +8 位作者 Yulin Liu Guangjun Guo Yong Lai Shan Qin Baoling Huang Zengjie Zheng Yinghui Sui Chao Li et al. 《Chinese Science Bulletin》 SCIE EI CAS 2000年第1期1-10,共10页
To develop and perfect the theory of plate tectonics and regional metallogeny, metal-logenesis during collisional orogenesis should be thoroughly studied and will attract increasing at-tention of more and more scienti... To develop and perfect the theory of plate tectonics and regional metallogeny, metal-logenesis during collisional orogenesis should be thoroughly studied and will attract increasing at-tention of more and more scientists. This paper presents the main aspects of research and discus-sions on metallogenesis during collisional orogenesis after the development of plate tectonics, and accordingly divides the study history into two stages, i.e. the junior stage during 1971-1990 and the senior stage after 1990. Beginning with the negation of mineralization in the collision regime by Guild (1971), the focus of study was put on whether there occurred any mineralization during collisional orogenesis at the junior stage. At the senior stage, which is initiated by the advance of met-allogenic and petrogenic model for collisional orogenesis, scientists begin to pay their attention to the geodynamic mechanism of metallogenesis, spatial and temporal distribution of ore deposits, ore-forming fluidization, relationship 展开更多
关键词 COLLISIONAL OROGENESIS METALLOGENESIS STUDY history PROGRESS frontier.
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