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Biomolecular Preservation of Miocene Fossil Liquidambar from Tiantai,China and Clarkia,USA:Implications for Palaeoenvironmental Study

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1076-1087页

作者： XIAO Liang YANG Hong HE Yuli HE Wenlong LI Xiangchuan GUO Junfeng hui kaixuan College of Earth Science and Resources and Key Laboratory of Western Mineral Resources and Geological Engineering Ministry of EducationChang’an University Laboratory of Terrestrial Environments Department of Science and TechnologyCollege of Arts and SciencesBryant University School of Earth Sciences and Key Laboratory of Mineral Resources in Western China (Gansu Province) Lanzhou University College of Geology and Environment Xi’an University of Science and Technology

Biomolecular characteristics of fossil Liquidambar from the Miocene Shengxian Formation, Tiantai, Zhejiang province in eastern China and Miocene Clarkia sediment, Idaho, U.S.A., are obtained by means of Pyrolysis-Gas chromatography-Mass spectrometry analysis （Py-GC-MS）. Their modern equivalent （Liquidambarformosana） collected from Nanjing, eastern China, is also analyzed for comparison. The total ion chromatograms （TIC） of modern L. formosana leaves shows abundant pyrolysates of iignin, polysaccharide, aliphatic acid, and amino acid. However, only one polysaccharide molecule, i.e., levoglucosan, is retained in fossil Liquidambar leaves from the two Miocene sites with the Tiantai specimen possessing higher intensity. As expected, some lignin pyrolysates including benzene, phenol, guaiacol, vinylphenol and their derivatives, are detected in Miocene Tiantai L. miosinica. However, the lignin components with large molecular weight other than benzene and phenol compounds, are absent in Miocene Clarkia L. pachyphyllum. Abundant pristene and homologous series of n-alk-l-ene/n-alkane pairs with a long retention time are shown in pyrograms of both Tiantai and Clarkia fossils. Based upon our Py-GC-MS data, the molecular preservation in these Liquidambar leaf samples can be ranked as the following （from high to low quality respectively）： modern sample 〉Tiantai sample 〉Clarkia sample. Vinyl phenol, an important compound, is present in modern and Tiantai Liquidambar leaves, while absent in Clarkia sample, implying that vinyl phenol may be sourced from lignin for Liquidambar leaves. Our data support the hypothesis of in situ polymerization for the origin of long-chain homologous series of n-alk-l-ene/n- alkane pairs as leaf alteration products. Our data have implications of the impact of leaf degradation toward biases for palaeoenvironmental reconstruction using stable carbon isotope of fossil plants, and suggest the importance of evaluating molecular preservation of fossil leaf t

关键词： Liquidambar Py-GC-MS Miocene Biomolecules palaeoenvironment

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岩浆热液型银矿床、银矿省及形成的控制因素

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岩石学报 2021年第8期37卷 2502-2520页

作者：回凯旋秦克章韩日赵俊兴王乐高燊张夏楠中国科学院矿产资源研究重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院地球科学研究院北京100029 中国科学院大学地球与行星科学学院北京100049 核资源与环境国家重点实验室东华理工大学南昌330013

岩浆热液型银矿床主要指与岩浆热液作用相关的独立银矿床和共生银矿床(Ag平均品位一般大于100g/t),它是银最重要的来源。本文对全球80多个典型的大型-超大型岩浆热液型银矿床进行了梳理和总结,将其主要分为浅成低温热液型(低硫型、中硫... 详细信息

岩浆热液型银矿床主要指与岩浆热液作用相关的独立银矿床和共生银矿床(Ag平均品位一般大于100g/t),它是银最重要的来源。本文对全球80多个典型的大型-超大型岩浆热液型银矿床进行了梳理和总结,将其主要分为浅成低温热液型(低硫型、中硫型和高硫型)、矽卡岩型、斑岩型和五元素型四种类型,其中浅成低温热液型占主导,斑岩型和矽卡型数量较少。全球大型-超大型的岩浆热液型银矿床主要分布在东太平洋俯冲带和中亚造山带东段,这些银矿床均位于陆壳基底之上。按照发育地区不同可分为六大银成矿省,即中国兴蒙银成矿省、美国西部盆岭银成矿省、墨西哥西北银成矿省、秘鲁中部银多金属成矿省、玻利维亚银锡成矿省和俄罗斯远东银锡成矿省。成矿时代主要集中在中、新生代。这些银成矿省与大规模酸性-中酸性岩浆活动密切相关,包括发育大量酸性熔结凝灰岩的长英质大火成岩省,或者富锡流纹岩、黄玉流纹岩和石英斑岩等高演化岩浆岩。这些大规模岩浆热液银成矿作用通常与区域大地构造背景转换相关,比如从挤压到伸展或者伸展到挤压。相对富银的含水大陆下地壳源区、大规模高分异的岩浆作用、银对熔体中共存硫化物和磁铁矿相对弱的相容性、高盐度的流体、成矿流体集中运移的通道和高效的沉淀机制是银大规模成矿的有利控制因素。银矿床的研究工作相对于铜、金矿床远远落后,银成矿省和酸性大火成岩省的内在联系、控制斑岩钼-银/锡-银两种银成矿系统的机制、岩浆演化对银成矿的控制、银矿潜力区的勘查找矿等关键问题仍亟待解决。

关键词：岩浆热液型银矿床矿床成因分类银矿省岩浆热液过程基底与构造背景问题与展望

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土耳其西部新生代斑岩成矿岩浆氧逸度-挥发份元素组成演化特征--来自锆石和磷灰石组成约束

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岩石学报 2021年第8期37卷 2339-2363页

作者：赵俊兴苏本勋 UYSAL I brahim AYDIN Faruk 肖燕 SEN Cuneyt 回凯旋秦克章中国科学院矿产资源研究重点实验室中国科学院地质与地球物理研究所北京100029 中国科学院地球科学研究院北京100029 中国科学院大学地球与行星科学学院北京100049 Department of Geological Engineering Karadeniz Technical UniversityTrabzon 61080 岩石圈演化国家重点实验室中国科学院地质与地球物理研究所北京100029

特提斯成矿域中段的土耳其西部集中产出了与俯冲、碰撞-后碰撞、伸展动力学背景有关的斑岩型铜、钼、金矿床。前人已完成了针对这些斑岩型矿床构造背景的大量研究工作,但对于区内不同构造背景下斑岩型矿床的成矿岩浆源区性质、成矿元素... 详细信息

特提斯成矿域中段的土耳其西部集中产出了与俯冲、碰撞-后碰撞、伸展动力学背景有关的斑岩型铜、钼、金矿床。前人已完成了针对这些斑岩型矿床构造背景的大量研究工作,但对于区内不同构造背景下斑岩型矿床的成矿岩浆源区性质、成矿元素-挥发分含量和成矿物质演化关系尚未有系统研究。而这些研究将对认识中特提斯构造域晚白垩世以来在新特提斯洋俯冲、欧亚板块-Tauride-Anatolide板块碰撞和伸展过程中斑岩矿床形成时地壳厚度、壳幔相互作用方式及成矿物质演化过程具有重要意义。本研究选择土耳其西段三个斑岩成矿带(Tavşanl带、Biga半岛成矿带和Afyon-Konya带)内五个斑岩型矿床的成矿岩体与同期侵入岩-火山岩,开展锆石微量元素和磷灰石主量元素研究,限定碰撞与伸展环境下斑岩型矿床成矿岩浆的形成温度、氧逸度条件及其与岩浆形成时地壳厚度的关系,利用磷灰石F-Cl-S含量组成揭示熔体挥发分和硫元素的物质组成,进而约束新特提斯洋俯冲-碰撞-伸展过程中斑岩系统的深部物质演化规律。研究结果表明,土耳其西部新生代斑岩型矿床成矿岩浆锆石大部分落于高水含量-高氧逸度区间,具有相似的稀土元素标准化配分曲线。从始新世到中新世,锆石氧逸度Ce 4+/Ce 3+比值呈现出先降低(斑岩型Cu-Mo矿到斑岩型Mo矿)后升高(斑岩型Mo-Cu矿到斑岩Au矿)的趋势,且相对于斑岩型Mo矿和Mo-Cu矿,斑岩型Au矿和Cu-Mo矿成矿岩体的锆石形成时具有相对较高的氧逸度。绝大部分斑岩型矿床成矿岩体的锆石Eu N/Eu N*位于0.4~0.7之间,但斑岩型Mo矿和斑岩型Mo-Cu矿床的锆石具有相对较低的Eu N/Eu N*比值,可能是由于在结晶时熔体受斜长石结晶影响较大。锆石微量元素显示(Yb/Gd和Hf/Y-Th/U)锆石组成大部分受岩浆房中角闪石±榍石±磷灰石分离结晶控制。根据锆石Ti温度计估算土耳其西部斑岩型矿床成矿岩体及其相关岩体的形成温度在650~900℃之间,结晶温度从斑岩型Au矿、斑岩型Cu-Mo/Mo-Cu矿至斑岩型Mo矿呈现递减趋势。对于熔体的挥发分与硫含量组成,始新世-渐新世斑岩型Cu-Mo与Mo矿床成矿岩浆相对具有高F和低Cl组成,中新世伸展环境形成的斑岩型Mo-Cu矿和斑岩型Au矿床成矿岩浆Cl含量普遍较高。与成矿岩体同期的暗色包体或基性岩脉中磷灰石计算获得的熔体硫含量均大于侵入体对应熔体的硫含量,且具有不均一的含量组成,表明基性岩浆注入可能为岩浆房提供硫。结合区域动力学和地壳厚度估算,本文认为触发土耳其西部新生代斑岩矿床形成的动力学机制是:在新特提斯洋向北单向汇聚的背景下,北部始新世-渐新世斑岩矿床受控于碰撞后俯冲的新特提斯洋板片(Vardar洋)后撤-回转-断离过程;南部中新世斑岩矿床的形成则受控于爱琴海板片俯冲控制的地壳伸展-减薄过程。北侧Izmir-Ankara-Erzincan缝合带附近的Tavşanl与Biga半岛斑岩成矿带始新世-渐新世斑岩型矿床的形成与熔融-同化-储存-均一过程(MASH)有关,深部地壳热区过程(DCHZ)与中新世Afyon-Konya带斑岩型矿床的形成有关。

关键词：斑岩矿床锆石微量元素岩浆氧逸度磷灰石主量元素成矿物质演化土耳其西部特提斯构造域

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Intent defined optical network with artificial intelligence-based automated operation and maintenance

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Science China(Information Sciences) 2020年第6期63卷 55-66页

作者： hui YANG kaixuan ZHAN Qiuyan YAO Xudong ZHAO Jie ZHANG Young LEE State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications Huawei Technologies Co. Ltd

Traditionally, the operation and maintenance of optical networks rely on the experience of engineers to configure network parameters, involving command-line interface, middle-ware scripting, and troubleshooting. However, with the emerging of newly B5 G applications, the traditional configuration cannot meet the requirement of real-time automatic configuration. Operators need a new configuration way without manual intervention at an underlying optical transport network. To cope with this issue, we propose an intent defined optical network(IDON) architecture toward artificial intelligence-based optical network automated operation and maintenance against service objective, by introducing a self-adapted generation and optimization(SAGO) policy in a customized manner. The IDON platform has three key innovations including intent-orient configuration translation, self-adapted generation and optimization policy, and close-loop intent guarantee operation. Focusing specifically on communication requirements, the IDON uses natural language processing to construct semantic graphs to understand, interact, and create the required network configuration. Then, deep reinforcement learning(DRL) is utilized to find the composition policy that satisfies the requirement of intent through the dynamic integration of fine-grained policies. Finally, the deep neural evolutionary network(DNEN) is introduced to achieve the intent guarantee at the milliseconds level. The feasibility and efficiency are verified on enhanced SDN testbed. Finally, we discuss several related challenges and opportunities for unveiling a promising upcoming future of intent defined optical network.

关键词： optical network artificial intelligence network automation intent defined network

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Rapid estimation of apple phenotypic parameters based on 3D reconstruction

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International Journal of Agricultural and Biological Engineering 2021年第5期14卷 180-188页

作者： Hao Ma Xu Zhu Jiangtao Ji hui Wang Xin Jin kaixuan Zhao College of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina

In order to obtain the phenotypic parameters of apple quickly and accurately,which were commonly used as the basis of fruit sorting,a fast estimation method of apple phenotypic parameters based on three-dimensional(3D)reconstruction was proposed in this *** this study,a three-dimensional model was constructed to estimate the phenotypic parameters of apple,such as volume,height,diameter,and fruit shape ***,an image acquisition system was built to capture sequence images of fruit with a binocular stereo vision system,and the images were extracted and matched using the Accelerated-KAZE algorithm to create the point cloud ***,the point cloud data were matched with the algorithm of Iterative Closest Point to establish a whole model of apple,and the surface reconstruction model of fruit was obtained by constructing irregular triangulation ***,the apple phenotypic parameters were calculated by means of segmentation,surface complement and integral of the fruit *** of 200 apples were used as samples in the *** this method,the phenotypic parameters of the apples were estimated based on their 3D reconstruction model,and the linear regression analysis was carried out between the estimated values and the real *** results showed that R2 of the linear regression fitting of each parameter was higher than *** them,the fitting of volume was the best with R2 of *** addition,the average errors of apple volume,height,fruit shape index,maximum diameter D and minimum diameter d were 8.73 cm3,1.43 mm,1.28%,0.90 mm,and 1.23 mm,*** to the Chinese national standard of“fresh Apple”,the average error of the estimated result is within the range of allowable *** indicates that the method of apple phenotypic parameter estimation based on 3D reconstruction has a high accuracy and practicability,and it can be used as the support for fruit sorting.

关键词： apple 3D reconstruction phenotypic parameter stereo vision system sequence image sorting

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Low-frequency variability of terrestrial water budget in China using GRACE satellite measurements from 2003 to 2010

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Geodesy and Geodynamics 2015年第6期6卷 444-452页

作者： Kang kaixuan Li hui Peng Peng Zou Zhengbo Key Laboratory of Earthquake Geodesy Institute of SeismologyChina Earthquake Administration Wuhan Base of Institute of Crustal Dynamics China Earthquake Administration State Key Laboratory of Geodesy and Earth's Dynamics Institute of Geodesy and GeophysicsChinese Academy of Sciences

Mass variations in terrestrial water storage（TWS） obtained from eight years of satellite data from the Gravity Recovery and Climate Experiment（GRACE） are used to describe low frequency TWS through Empirical Orthogonal Function（EOF） analysis. Results of the second seasonal EOF mode show the influence of the Meiyu season. Annual variability is clearly shown in the precipitation distribution over China, and two new patterns of interannual variability are presented for the first time from observations, where two periods of abrupt acceleration are seen in 2004 and 2008. GRACE successfully measures drought events in southern China, and in this respect, an association with the Arctic Oscillation and El Nino-Southern Oscillation is discussed. This study demonstrates the unique potential of satellite gravity measurements in monitoring TWS variations and large-scale severe drought in China.

关键词： Gravity recovery and climate experiment(GRACE) Terrestrial water storage Drought event Global hydrology models Water vapor transport Drought event Empirical orthogonal function(EOF) El Nino-southern oscillation(ENSO)

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Pseudotime Ordering Single-Cell Transcriptomic ofβCells Pancreatic Islets in Health and Type 2 Diabetes

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Phenomics 2021年第5期1卷 199-210页

作者： kaixuan Bao Zhicheng Cui hui Wang hui Xiao Ting Li Xingxing Kong Tiemin Liu Human Phenome Institute Fudan University825 Zhangheng RoadShanghai 201203China State Key Laboratory of Genetic Engineering School of Life Sciencesand Collaborative Innovation Center for Genetics and DevelopmentFudan UniversityShanghai 200438China Shanghai Key Laboratory of Metabolic Remodeling and Health Institute of Metabolism and Integrative BiologyFudan UniversityShanghai 200433China Department of Endocrinology and Metabolism Zhongshan HospitalFudan UniversityShanghai 200032China

βcells are defined by the ability to produce and secret *** studies have evaluated that human pancreaticβcells are heterogeneous and demonstrated the transcript alterations ofβcell subpopulation in ***-cell RNA sequence(scRNA-seq)analysis helps us to refine the cell types signatures and understand the role of theβcells during metabolic challenges and ***,we construct the pseudotime trajectory ofβcells from publicly available scRNA-seq data in health and type 2 diabetes(T2D)based on highly dispersed and highly expressed genes using *** identified three major states including 1)Normal branch,2)Obesity-like branch and 3)T2D-like branch based on biomarker genes and genes that give rise to bifurcation in the trajectory.βcell function-maintain-related genes,insulin expression-related genes,and T2D-related genes enriched in three branches,*** pseudotime spectrum might suggest thatβcells transition among different *** application of pseudotime analysis is conducted to clarify the different cell states,providing novel insights into the pathology ofβcells in T2D.

关键词： Single-cell RNA seq Islets βcell Pseudotime T2D

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Gravity anomaly before the Leshan M5.0 earthquake?

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Geodesy and Geodynamics 2015年第2期6卷 101-105页

作者： Wei Jin Liu Ziwei Sun Shaoan Kang kaixuan Shen Chongyang Li hui Key Laboratory of Earthquake Geodesy Institute of Seismology China Earthquake Administration Wuhan Base of Institute of Crustal Dynamics China Earthquake Administration School of Geodesy and Geomatics Wuhan University

The North-South Seismic Belt was analyzed using gravity observation data from 2011 to 2015, and the nontidal analysis results show that there was a nonlinear gravity change at both the Chengdu and Guza seismostations ... 详细信息

关键词： Gravity gradient Continuous gravity observations Nonlinear gravity change Leshan M5.0 earthquake Mobile gravity observation network Accumulation gravity change Different gravity change North-South Seismic Belt

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Development and evaluation of a thermostatic nucleic acid testing device based on magnesium pyrophosphate precipitation for detecting Enterocytozoon hepatopenaei

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Chinese Chemical Letters 2022年第8期33卷 4053-4056页

作者： Zhu Chen kaixuan Zhao Ziyu He Xiaofang Luo Zuodong Qin Yimin Tan Xiangming Zheng Zuozhong Wu Yan Deng hui Chen Yuan Guo Song Li Hunan Key Laboratory of Biomedical Nanomaterials and Devices Hunan University of TechnologyZhuzhou 412007China Department of Cardiovascular Medicine The Affiliated Zhuzhou Hospital Xiangya Medical CollegeCentral South UniversityZhuzhou 412000China Institute of Supramolecular Structures and Micro-nano Materials Hunan University of TechnologyZhuzhou 412007China National&Local Joint Engineering Research Center for Research and Technology of Advanced Packaging Materials Hunan University of TechnologyZhuzhou 412007China Hunan Shengzhou Biotechnology Ltd. Zhuzhou 412000China College of Chemistry and Bioengineering Hunan University of Science and EngineeringYongzhou 425199China

Enterocytozoon hepatopenaei(EHP)infection has seriously affected prawn culture *** symptoms of the infection are not apparent,and traditional detection methods are time consuming and low in *** developed a new onsite rapid testing device(size 18.8×16.7×6.6 cm^(3))for EHP based on magnesium pyrophosphate precipitation and facilitated by loop mediated isothermal amplification(LAMP).The design and fabrication of the device enables efficient light *** device has a highly sensitive detector,high-precision thermal controller,and humanized touch *** temperature control precision of the device is 0.2-0.3℃ at 60℃,63℃,and 65℃.The coefficients of variation values(CVV)of the luminous power in one channel at light on and off were found to be 0.0097 and 0.0014,respectively,within 1 *** CVV of the background,luminous power,and values of eight PCR tubes filled with pure water were all less than 5%.In the EHP experiment,eight samples(including seven positive and one negative)confirmed the effectiveness of the device,and four positive and four negative samples verified whether cross-contamination *** them,the rise time of the curve was about 15 *** results assert that the developed device exhibits enhanced stability and uniformity and has excellent performance with high sensitivity,good specificity,and low testing ***,the optimal and minimum absorbance range was 555-655 nm for monitoring the production of LAMP.

关键词： Turbidity detection Magnesium pyrophosphate precipitation Nucleic acid testing Enterocytozoon hepatopenaei Loop-mediated isothermal amplification

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Characteristics of satellite-gravity variations in the North-South Seismic Belt before the 2013 Lushan earthquake

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Geodesy and Geodynamics 2013年第3期4卷 1-6页

作者： Zou Zhengbo Li hui Kang kaixuan Wu Yunlong Key Laboratory of Earthquake Geodesy China Earthquake Administration Wuhan Base of Institute of Crustal Dynamics China Earthquake Administration School of Geodesy and Geomatics Wuhan University

To study the characteristics of gravity variations in and near the North-South Seismic Belt before the 2013 Lushan earthquake,we used the geopotential-field models based on monthly data of the RI.~5 GRACE satellite to calculate the gravity changes. Here we present the patterns of annually cumulative variation, differentiatial variation and secular trend, as well as the continuous time-series at 4 characteristic sites during 2004 -2012. The result shows that the anomalous positive-to-negative transition zone, in which the epicenter of the 2008 Wenchuan earthquake was located, did not show any new gravity change before the Lushan earthquake, though located in the same zone.

关键词： satellite gravity gravity variation earthquake time series North-South Seismic Belt

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