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Elevation of basal lacustrine sediments along the mid-lower reaches of the Yangtze River and its implications for the reconstruction of Holocene water levels

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Science China Earth Sciences 2024年第9期67卷 2924-2936页

作者： Shuchun YAO chunhai li Bin XUE Nanjing Institute of Geography and limnology Chinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China

The middle and lower reaches of the Yangtze River,a primary region for freshwater lakes in China,have undergone significant transformations throughout the *** changes,driven by factors such as sea-level rise,climate change,and human activities,have led to the progressive elevation of water levels in this *** a result,a floodplain has emerged,characterized by the formation of numerous shallow lakes along the river ***,the pattern of water-level changes in the main channel of the Yangtze River during the Holocene remains *** gap in knowledge poses challenges for understanding sediment transport dynamics,the interactions between the river and its adjacent lakes,and the prevention and control of flood disasters in the Yangtze River *** shed light on these issues,our study compiled data on the surface elevation and water depth of 81 lakes in the mid-lower reaches of the Yangtze River ***,we analyzed historical water-level records from the 1900s to the 1970s at eight gauging stations from Shashi to Jiangyin along the river’s main *** findings reveal that,particularly along the Jingjiang section,the basal elevation of most lakes is lower than the Yangtze River’s water level during the dry ***,the water level of the main stream exceeds that of both the floodplain and the lakes enclosed by the Jingjiang *** the tidal reach,especially within the Taihu Lake basin,the basal elevation of lakes typically falls below sea ***,lakes located along the section from Chenglingji to Wuhu exhibit basal elevations that correspond with the Yangtze River’s annual average and dry season water *** the widespread presence of lakes along the middle and lower reaches of the Yangtze River,our study introduces a new proxy for reconstructing the mean water level of the mid-lower Yangtze River in the *** analyzing sediments from Nanyi Lake and Chenyao Lake in the lower Yangtze River,we a

关键词： Middle and lower Yangtze River Holocene Water level Floodplain lakes Basal sediment elevation

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A Blockchain-Based Efficient Cross-Domain Authentication Scheme for Internet of Vehicles

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Computers, Materials & Continua 2024年第7期80卷 567-585页

作者： Feng Zhao Hongtao Ding chunhai li Zhaoyu Su Guoling liang Changsong Yang Guangxi Engineering Research Center of Industrial Internet Security and Blockchain Guilin University of Electronic TechnologyGuilin541004China School of Information and Communication Guilin University of Electronic TechnologyGuilin541004China School of Computer Science and Information Security Guilin University of Electronic TechnologyGuilin541004China

The Internet of Vehicles(IoV)is extensively deployed in outdoor and open environments to effectively address traffic efficiency and safety issues by connecting vehicles to the ***,due to the open and variable nature of its network topology,vehicles frequently engage in cross-domain *** such processes,directly uploading sensitive information to roadside units for interaction may expose it to malicious tampering or interception by attackers,thus compromising the security of the cross-domain authentication ***,IoV imposes high real-time requirements,and existing cross-domain authentication schemes for IoV often encounter efficiency *** mitigate these challenges,we propose CAIoV,a blockchain-based efficient cross-domain authentication scheme for *** scheme comprehensively integrates technologies such as zero-knowledge proofs,smart contracts,and Merkle hash tree *** divides the cross-domain process into anonymous cross-domain authentication and safe cross-domain authentication phases to ensure efficiency while maintaining a balance between efficiency and ***,we evaluate the performance of *** results demonstrate that our proposed scheme reduces computational overhead by approximately 20%,communication overhead by around 10%,and storage overhead by nearly 30%.

关键词： Blockchain cross-domain authentication internet of vehicle zero-knowledge proof

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基于聚合物膜片和光纤复合结构的局部放电声传感器

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传感器与微系统 2024年第7期43卷 92-96页

作者：李如锋杨军李春海国网雄安新区供电公司河北保定070001 武汉大学电气工程学院湖北武汉430072 石家庄科林电气股份有限公司河北石家庄050000

本文提出了一种基于聚合物膜片和单模—多模—单模光纤复合结构的用于局部放电探测的声传感器。将长度为5cm的多模光纤植入单模光纤之间作为声敏感单元。当光从单模光纤进入多模光纤时,会激发光纤内的高阶模式形成干涉,以实现声传感,并... 详细信息

本文提出了一种基于聚合物膜片和单模—多模—单模光纤复合结构的用于局部放电探测的声传感器。将长度为5cm的多模光纤植入单模光纤之间作为声敏感单元。当光从单模光纤进入多模光纤时,会激发光纤内的高阶模式形成干涉,以实现声传感,并将该光纤串入聚合物膜片中,用于改善其灵敏度。实验结果表明:该传感器在空气中的声传感灵敏度可达-30.8 dBm(0 dBm定义为1 V/μBar)。根据IEC 60270标准分别在空气和油介质中对传感器进行了局部放电声传感测试证明了该方案的可行性。由于其结构简单、成本低廉和不受电磁干扰等优点,该传感器有望在电力设备局部放电检测等领域得到应用。

关键词：局部放电光纤传感声传感聚合物膜片

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抗病籼型水稻光温敏核不育系华1228S的选育及应用

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杂交水稻 2024年第1期39卷 68-73页

作者：米甲明李春海熊立仲牟同敏华中农业大学作物遗传改良全国重点实验室湖北武汉430070

华1228S是以广占63-4S为受体亲本,以携带Xa7基因的抗白叶枯病株系材料YR7029-39和携带Pi2基因的抗稻瘟病株系材料VE6219作供体亲本,通过杂交、回交、复交和分子标记辅助选择进行基因聚合选育而成的抗稻瘟病、抗白叶枯病籼型水稻光温敏... 详细信息

华1228S是以广占63-4S为受体亲本,以携带Xa7基因的抗白叶枯病株系材料YR7029-39和携带Pi2基因的抗稻瘟病株系材料VE6219作供体亲本,通过杂交、回交、复交和分子标记辅助选择进行基因聚合选育而成的抗稻瘟病、抗白叶枯病籼型水稻光温敏核不育系。以华1228S为母本已经配组了10个杂交稻组合通过审定,其中2个通过国审、8个通过湖北省审定。

关键词：杂交水稻光温敏核不育系华1228S 抗病稻瘟病白叶枯病分子标记辅助选择

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Changes of vegetation in southern China

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Science China Earth Sciences 2019年第8期62卷 1316-1328页

作者： Weiming WANG chunhai li Junwu SHU Wei CHEN CAS Key Laboratory of Economic Stratigraphy and Palaeogeography Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PaleoenvironmentChinese Academy of SciencesNanjing210008China State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing210008China

In order to reveal the changes of vegetation in southern China since the Last Glacial Maximum, we have established high-resolution time scales and palynological sequences of borehole profiles by drilling cores in some weak areas of the research to restore vegetation changes over the past 20,000 years on the basis of previous work. This paper gives the vegetation zoning maps of 18, 9 and 6 ka BP respectively in southern China, and describes the distribution characteristics of plants in different zones/subzones. The results show that the vegetation zonations around 18 ka BP were significantly different from that at *** appeared in turn with Cold-temperate coniferous forest and alpine meadow steppe zone, and Temperate mixed coniferous and broad-leaved forest zone/warm temperate deciduous broad-leaved forest zone from northwest to southeast in the west, and Temperate mixed coniferous and broad-leaved forest zone, Warm temperate deciduous broad-leaved forest zone, and Northern subtropical mixed evergreen and deciduous broad-leaved forest zone from north to south in the central and east. The vegetation distribution around 9 ka BP changed distinctively. Except that the northwest part was located in Mountain temperate mixed coniferous and broad-leaved forest zone, the vegetation in other areas occurred in turn with North subtropical mixed evergreen and deciduous broad-leaved forest subzone, Mid-subtropical typical evergreen broad-leaved forest subzone, and South subtropical monsoon evergreen broad-leaved forest subzone/Tropical seasonal rainforest and rainforest zone from north to *** was little change in the appearance of vegetation zonations between 6 and 9 ka BP, but the northern edge of each vegetation belt moved a little northward, reflecting that the overall climate became warmer around 6 ka BP. The vegetation changes in southern China over the past 20,000 years were largely driven by environmental changes. Climate change was the main factor affecting t

关键词： Vegetation changes 18 ka BP 9 ka BP 6 ka BP Environmental change Southern China

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Bifurcations and Single Peak Solitary Wave Solutions of an Integrable NonlinearWave Equation

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Advances in Applied Mathematics and Mechanics 2016年第6期8卷 1084-1098页

作者： WeiWang chunhai li Wenjing Zhu School of Mathematics and Computing Science Guilin University of Electronic TechnologyJinji Road No.1Guilin 541004China

Dynamical system theory is applied to the integrable nonlinear wave equation ut±(u^(3)−u^(2))x+(u^(3))xxx=*** obtain the single peak solitary wave solutions and compacton solutions of the *** compacton solution of the equation correspond to the case of wave speed c=*** the case of c 6=0,we find smooth soliton *** influence of parameters of the traveling wave solutions is explored by using the phase portrait analytical *** analysis and numerical simulations are provided for these soliton solutions of the nonlinear wave equation.

关键词： Bifurcation solitary wave compaction

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An aggregate flow based scheduler in multi-task cooperated UAVs network

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Chinese Journal of Aeronautics 2020年第11期33卷 2989-2998页

作者： Xiaohuan li Ziqi XIE Jin YE Xin TANG chunhai li Fengzhu TANG Rong YU School of Information and Communication Guilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory of Multimedia Communications and Network Technology School of ComputerElectronics and InformationGuangxi UniversityNanning 530004China National Engineering Laboratory for Comprehensive Transportation Big Data Application Technology(Guangxi) Nanning 530001China School of Automation Guangdong University of TechnologyGuangzhou 510006China

Unmanned Aerial Vehicles(UAVs)cooperative multi-task system has become the research focus in recent ***,the existing network frameworks of UAVs are not flexible and efficient enough to deal with the complex multi-task scheduling,because they are not able to perceive the different *** this paper,a novel cooperated UAVs network framework for multi-task scheduling is *** is a three-layer network including a core layer,an aggregation layer and an execution layer,which enhances the efficiency of multi-task distribution,aggregation and ***,an Aggre Gate Flow(AGFlow)based scheduler is dedicatedly designed to maximize the task completion rate,whose key point is to aggregate flows belonging to one task during the multi-task transmission of UAVs network and to allocate priority by calculating the urgency-level of each *** results demonstrate that,compared with that of state-of-the-art scheduler,the average task completion rate of AGFlow based scheduler is raised by 0.278.

关键词： Mixed-flow scheduling Multi-task Task completion rate Unmanned Aerial Vehicles(UAVs) Urgency-level

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Establishment and evaluation of a rat model of complete transected spinal cord injury

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Neural Regeneration Research 2008年第4期3卷 367-371页

作者： Xuejun li chunhai Huang Shangming liu Xianrui Yuan Department of Neurosurgery Xiangya Hospital of Central South University Changsha 410008 Hunan Province China

BACKGROUND： The establishment of a rat model of complete transected spinal cord injury lacks technological specifications. The current models lack concordance and reliability, and the death rate of the experimental animals is high. Therefore, there is a great need for a reliable model to apply clinical applications of therapy. OBJECTIVE： To construct a rat model of complete transected spinal cord injury characterized by stability, reproducibility, and a high animal survival rate. DESIGN： Completely randomized controlled study. SETTING： Department of Neurosurgery, Xiangya Hospital of Central South University. MATERIALS： Fifty-five healthy specific pathogen free grade adult female Sprague Dawley rats were provided by the Experimental Animal Department, Xiangya Medical College, Central South University. Olympus BX51 imaging collecting analytic system was provided by Olympus Company, Japan; and SEN-7203 Nihon-Kohden electrical stimulator by Nihon Kohden, Japan. METHODS： This study was performed at the Laboratory of Neurosurgery, Xiangya Hospital of Central South University from April to June 2006. Experimental grouping： 55 rats were randomly divided into model group （n = 40） and sham surgery group （n = 15）. In the model group, a self-made sliver hook was passed through the ventral side to support the spinal cord at the T12 segment and to shear it off. A complete transected spinal cord, 2 mm in length, was resected. In the sham surgery group, the spinal cord was identically exposed. The dura mater of the spinal cord was cut open, but the spinal cord was not damaged. MAIN OUTCOME MEASURES： Histopathological changes after spinal cord injury at L2 segment were observed subsequent to hematoxylin and eosin staining under optical microscopy. Olympus BX51 imaging collecting analytic system was used to count spinal cord ventral horn neurons. Motor function of rat hindlimb was evaluated with the Basso, Beattie and Bresnahan （BBB） scale. Paraplegia was evaluated as 0 point, and co

关键词： spinal cord injury complete transected models, animal rats

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Graded interface engineering of 3D/2D halide perovskite solar cells through ultrathin(PEA)_(2)PbI_(4) nanosheets

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Chinese Chemical Letters 2021年第7期32卷 2259-2262页

作者： lijie Zhu Qipeng Lu chunhai li Yue Wang Zhenbo Deng Key Laboratory of Luminescence and Optical Information Ministry of EducationBeijing JiaoTong UniversityBeijing 100044China School of Instrument Science and Opto-Electronics Engineering Beijing Information Science and Technology UniversityBeijing 100192China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

2D halide perovskites have emerged as promising materials because of their stability and passivation effect in perovskite solar cells(PSCs).However,the introduction of bulky organic ammonium cations from 2D halide perovskites would decrease the device performance generally compared to the traditional 3D MAPbI_(3).Incorporation of ultrathin 2D halide perovskite nanosheets(NSs)with 3D MAPbI_(3)could address this ***,we re port a rationally designed PSCs with dimensional graded 3D/2D MAPbI_(3)/(PEA)_(2)PbI_(4)heterojunction,in which 2D(PEA)_(2)PbI_(4)NSs were synthesized and incorporated between 3D MAPbI_(3)and hole-transporting *** the significantly improved stability,a notable increasement in power conversion efficiency(PCE)of 20%was obtained for the 3D/2D perovskite solar cells due to the favourable band alignment among(PEA)_(2)PbI_(4)NSs and the other *** graded structure of MAPbI_(3)/(PEA)_(2)PbI_(4)would upshift the energy level continuously,which enhances the hole extraction efficiency thus reduces the interface charge recombination,leading to the increasements of VOC from1.04 V to 1.07 V,Jsc from 21.81 mA/cm^(2) to 23.15 mA/cm^(2) and the fill factor from 67.89% to 74.78%,and therefore an overall PCE of 18.53%.

关键词： Interface engineering Perovskite solar cell Two-dimensional perovskite Hole extraction layer Band alignment

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胃癌患者血清miR-216b和miR-132水平表达与临床预后的关系研究

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现代检验医学杂志 2024年第3期39卷 98-102,141页

作者：吕宗峻李春海王晓东佳木斯市中心医院普外二科黑龙江佳木斯154002

目的探讨胃癌患者血清miR-216b和miR-132水平表达与临床预后的关系。方法选取2018年1月~2020年2月在佳木斯市中心医院就诊的87例胃癌患者作为胃癌组,选择同期87例健康体检者作为对照组。实时荧光定量PCR (quantitative real-time PCR,... 详细信息

目的探讨胃癌患者血清miR-216b和miR-132水平表达与临床预后的关系。方法选取2018年1月~2020年2月在佳木斯市中心医院就诊的87例胃癌患者作为胃癌组,选择同期87例健康体检者作为对照组。实时荧光定量PCR (quantitative real-time PCR,qRT-PCR)检测血清中miR-216b和miR-132表达水平,分析胃癌患者血清miR-216b和miR-132表达水平与临床病理特征的关系。根据胃癌患者随访期间的生存或死亡情况,将胃癌患者分为预后良好组(生存,n=51)和预后不良组(死亡,n=36),用受试者工作特征(receiver operating characteristic,ROC)曲线分析血清miR-216b和miR-132表达水平对胃癌患者预后的预测价值;COX回归分析影响胃癌患者预后的因素。结果与对照组比较,胃癌组血清中miR-216b (0.69±0.20 vs 1.02±0.24)和miR-132 (0.73±0.19 vs 1.01±0.22)表达水平降低,差异具有统计学意义(t=9.853,8.984,均P<0.001)。分化程度为低分化、TNM分期为Ⅲ±Ⅳ期、有淋巴结转移、有远处转移的胃癌患者血清miR-216b,miR-132表达水平低于分化程度为中、高分化、TNM分期为Ⅰ±Ⅱ期、无淋巴结转移、无远处转移的胃癌患者,差异具有统计学意义(t=6.266,3.412,2.890,2.723;4.999,3.734,4.180,5.502,均P<0.05)。与预后良好组比较,预后不良组胃癌患者血清中miR-216b(0.56±0.16vs 0.78±0.23)和miR-132(0.60±0.11 vs 0.82±0.25)表达水平降低,差异具有统计学意义(t=4.952,4.946,均P<0.001)。血清miR-216b,miR-132及二者联合预测胃癌患者预后的曲线下面积(area under the cure,AUC)分别为0.797 (95%CI:0.706~0.889),0.832(95%CI:0.745~0.918)和0.900 (95%CI:0.836~0.964);敏感度和特异度分别为83.3%,68.6%;97.2%,62.7%和79.4%,72.5%;当血清miR-216b,miR-132预测胃癌患者预后不良的截断值分别为0.66,0.76时,预测的敏感度较高。COX回归分析显示,miR-216b低表达、miR-132低表达、分化程度为低分化、TNM分期为Ⅲ+Ⅳ期、有淋巴结转移、有远处转移是胃癌患者预后不良的危险因素(均P<0.05)。结论miR-216b和miR-132在胃癌患者血清中呈低表达,二者可作为预测胃癌患者预后的有效生物标志物。

关键词：胃癌微小核糖核酸-216b 微小核糖核酸-132

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