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Geochronology of recent lake sediments from Longgan Lake,middle reach of the yangtze River,influenced by disturbance of human activities

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Science China Earth Sciences 2010年第8期53卷 1188-1194页

作者： WU YanHong LIU EnFeng BING HaiJian yang xiangdong XUE Bin XIA WeiLan State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China Graduate University of Chinese Academy of Sciences Beijing 100049China

The impacts of human activities in Longgan Lake region on the distribution of 210Pb in lake sediment made it difficult to establish geochronological sequence. However, environmental proxies recorded these human activities and could be used as time marker to check 210Pb dating results. Based on the analysis of 210Pbexc distribution in cores LS-1 and LGL-1, and in combination with the human activities records in grain-size and element concentration, the sedimentation rates in the upper layers of these two cores were determined to be 0.19 and 0.23 cm/a respectively. The MAR (mass accumulation rates) of these two cores demonstrated that natural condition, such as precipitation and runoffs, led to the variation of MAR before human disturbance, and human activities controlled the sedimentary processes afterwards, which obviously reduced the particles influx into the lakes. During 1940s when human activity had not changed the water system within the catchment, 210Pb activity was abnormally strong in lakes along middle to lower reaches of the yangtze River, which might be attributed to less precipitation and can be used as a time marker for geochronological research.

关键词： 210Pb geochronology environmental index human activity Longgan Lake

自体动静脉内瘘维持性血液透析患者腹主动脉钙化预测模型的构建

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西部医学 2024年第2期36卷 222-227页

作者：任丽丽郭宁冯静静杨惠敏杨向东山东大学齐鲁医院血液透析中心山东济南250012 齐河县人民医院肾内科山东德州251100

目的利用临床常见资料构建自体动静脉内瘘(AVF)维持性血液透析患者发生腹主动脉钙化(AAC)的列线图预测模型。方法选取2019年1月—2022年10月山东大学齐鲁医院血液净化中心的维持性血液透析患者175例,依据其是否发生AAC分为AAC组(140例... 详细信息

目的利用临床常见资料构建自体动静脉内瘘(AVF)维持性血液透析患者发生腹主动脉钙化(AAC)的列线图预测模型。方法选取2019年1月—2022年10月山东大学齐鲁医院血液净化中心的维持性血液透析患者175例,依据其是否发生AAC分为AAC组(140例)和非AAC组(35例),收集所有患者一般资料和相关实验室检查信息以构建列线图预测模型。结果 AAC组血压、维持透析时间、Hb、红细胞压积(HCT)较非AAC组更高(P<0.05)。依据Lasso回归分析筛选出年龄、患有糖尿病、BMI、舒张压、维持透析时间、Hb、甲状旁腺激素(PTH)、白蛋白(Alb)、总铁结合力(TIBC)构建了发生AAC的列线图预测模型,ROC下面积(AUC)为0.84[95%CI(0.76, 0.89)],模型精准率为0.96。决策曲线(DCA)提示使用该模型能够使患者获益度增加,校准曲线(CA)提示该模型预测结果与实际结果一致性良好。结论基于Lasso回归筛选预测变量构建AVF维持性血液透析患者发生AAC的列线图预测模型,该模型有良好的准确率和区分度,为维持性血液透析患者血管钙化管理提供参考依据。

关键词：血液透析动静脉内瘘腹主动脉硬化预测模型

基于遗传算法的数字孪生智慧水利控制系统设计

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自动化应用 2024年第17期65卷 57-62,65页

作者：岑淑桢杨向东夏靖邦陈黄飞广州华立学院广东广州511300

介绍了一种基于遗传算法的数字孪生智慧水利控制系统设计方法。该方法应用数字孪生技术构建智慧水利系统,以应对全球水资源紧缺和水灾频发的问题。通过建立数字孪生模型和结合物联网、云计算、人工智能等技术,实时监测和智能化控制水利... 详细信息

介绍了一种基于遗传算法的数字孪生智慧水利控制系统设计方法。该方法应用数字孪生技术构建智慧水利系统,以应对全球水资源紧缺和水灾频发的问题。通过建立数字孪生模型和结合物联网、云计算、人工智能等技术,实时监测和智能化控制水利系统。研究内容包括液压控制系统在大坝中的应用、智能灯光控制系统的设计、数字孪生模型的建立、实时监测和智能化控制的实现以及优化分析等。同时,深入探讨了数字孪生智慧水利项目所面临的难题和具体意义。最后,提出了一套完整的技术路线,以解决水资源管理效率低下、自然灾害防范不足、水质污染治理困难和水利工程运行维护成本高等问题。

关键词：数字孪生技术智慧水利系统液压控制系统智能灯光控制物联网

Lattice instability of V_2AlC at high pressure

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Science China(Physics,Mechanics & Astronomy) 2013年第5期56卷 916-924页

作者： yang ZeJin LIU Qiang LI Jin WANG Zhao GUO AiMin LINGHU RongFeng CHENG XinLu yang xiangdong School of Physics Zhejiang University of Technology School of Physics Chongqing University of Technology College of Material and Chemical Engineering Hainan Provincial Key Laboratory of Research on Utilization of Si-Zr-Ti ResourcesHainan University Institute of Physics Chinese Academy of Sciences School of Physics Guizhou Normal College Institute of Atomic and Molecular Physics Sichuan University

We investigate the elastic and thermodynamic properties of nanolaminate VzA1C by using the ab initio pseudopotential total energy method. The axial compressibility shows that the c axis is always stiffer than a axis. The elastic constants revealed the structural instability at about 500 and 732 GPa. Furthermore, elastic constants C44 reached its maximum at about 550 GPa, dif- fering with the other four C^1, G2, C13 and 6＂33 constants. The Poisson＇s ratio investigations demonstrated that a higher ionic or weaker covalent contribution in intra-atomic bonding and the degree of ionicity increases with pressure. The G/B and B]C44 investigations revealed that VzAIC is brittle and the brittleness decreases with pressure. Also, we found that V2A1C is elastic anisotropic materials and the degree of anisotropy rapidly rises with pressure. Study on Debye temperature and Grtineisen pa- rameter observed weak temperature and strong pressure responses, whereas the sensitive dependence in the thermal expansion coefficient and Helmholtz free energy are clearly seen.

关键词： elasticity thermodynamicity first principles

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旅游歌曲对丽江市地方形象构建研究

文山学院学报 2024年第2期37卷 40-47页

作者：戴镇涛徐丽姣和珑杨向东昆明文理学院云南昆明650221 丽江佳润农业科技有限公司云南丽江674100

音乐与地方互相创造彼此,独特的地域风土激发着音乐创作,所创音乐又不断的塑造着地域形象,音乐所塑造的地方意象激发听者对该旅游地的依恋与向往。旅游歌曲在提升区域旅游目的地形象方面发挥着至关重要的影响。为研究和探讨旅游歌曲对... 详细信息

音乐与地方互相创造彼此,独特的地域风土激发着音乐创作,所创音乐又不断的塑造着地域形象,音乐所塑造的地方意象激发听者对该旅游地的依恋与向往。旅游歌曲在提升区域旅游目的地形象方面发挥着至关重要的影响。为研究和探讨旅游歌曲对丽江形象的构建,通过影视剧、地方宣传片、QQ音乐、百度音乐、相应书籍以及抖音等短视频、百度等其他互联网媒体进行筛选、收集与分析,对114首丽江旅游歌曲进行词频分析,从而得出丽江旅游歌曲对区域的意象构建。在自然意象构建方面,歌词构建的区域自然意象与丽江市自然特点息息相关;在人文意象方面,丽江旅游歌曲构建出一个多民族的“家”的、“爱情”的人文意象。

关键词：旅游歌曲地方形象建构丽江市

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tsRNA在急性心肌梗死早期诊断中的价值

中国临床医学 2024年第3期31卷 402-410页

作者：刘雯张志伟杨茜洋朱小伟杨向东丁素玲复旦大学附属中山医院心脏超声诊断科上海200032 复旦大学附属中山医院心血管病研究所上海200032 复旦大学附属中山医院生殖医学中心上海200032 复旦大学生物医学研究院上海200032 复旦大学附属中山医院吴淞医院心内科上海200940

目的探讨转运RNA衍生的小RNA(transfer RNA-derived small RNA,tsRNA)在急性心肌梗死(AMI)早期诊断中的价值及其作为AMI诊断标志物的潜能。方法将年龄及体质量匹配的雄性C57小鼠(8~10周龄)随机分为MI组及对照组(Sham组),每组4只。两... 详细信息

目的探讨转运RNA衍生的小RNA(transfer RNA-derived small RNA,tsRNA)在急性心肌梗死(AMI)早期诊断中的价值及其作为AMI诊断标志物的潜能。方法将年龄及体质量匹配的雄性C57小鼠(8~10周龄)随机分为MI组及对照组(Sham组),每组4只。两组均于建模24 h后提取左室心肌组织RNA,经去修饰预处理,连接人工化接头后扩增,筛选包含15~40个核苷酸的小RNA扩增产物,构建文库并测序,将测序结果与GtRNAdb数据库成熟的t RNA和tRNA前体序列比对,获得在AMI前后心肌中差异表达的tsRNA谱。采用生物信息学分析同一密码子对应的tRNA在AMI前后剪切方式的改变。依据AMI前后tsRNA表达谱差异,获得在AMI后特异性高丰度表达的tsRNA,并在AMI小鼠心肌和血浆中验证,探讨tsRNA作为AMI诊断标志物的潜能。结果 tsRNA表达谱在组内有较好的重复性,组间差异较大。发生AMI后,Asn-GTT、Glu-TTC、Gly-ACC、Gly-GCC、His-GTG、Ile-AAT、Ile-GAT、Pro-TGG、Ser-AGA和Trp-CCA在心肌中剪切方式发生改变,生成有明显差异的tsRNA表达谱。与Sham组相比,MI组有268个tsRNA表达上调,1 228个tsRNA表达下调,且有64个特异性tsRNA。AMI建模第1天,小鼠tRF-Gly-CCC-2-31、tiRNA-Val-CAC-1-32、tiRNA-ValAAC-2-32、tiRNA-Glu-TTC-2-32和tiRNA-Lys-TTT-1-34在心肌中特异性表达,其中tiRNA-Val-AAC-2-32和tiRNA-LysTTT-1-34在AMI小鼠血浆中特异性高丰度表达,并随AMI持续时间动态变化。结论 tsRNA表达谱在AMI前后差异显著,其中在小鼠心肌和血浆中特异性表达的tiRNA-Val-AAC-2-32和tiRNA-Lys-TTT-1-34有AMI诊断潜能,可能在AMI修复过程中发挥重要作用。

关键词：转运RNA衍生小片段急性心肌梗死生物信息学诊断标志物

A 16000-year pollen record of Qinghai Lake and its paleoclimate and paleoenvironment

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Chinese Science Bulletin 2002年第22期47卷 1931-1936页

作者： LIU Xingqi SHEN Ji WANG Sumin yang xiangdong TONG Guobang ZHANG Enlou Key Laboratory of Lake Sedimentation and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China Institute of Hydrological and Environmental Geology Chinese Academy of Geological SciencesZhengding 050803China

The paleoclimate and paleoenvironment of Qinghai Lake indicated by a 16000-year pollen record are as follows. It was very cold and dry before 15200 years. During the Late Glacial, the climate varied from colder and semiarid to cool and semi-humid and fluctuated frequently but with little amplitude. Three cold events in the periods of 13400-13000, 11600-12000, and 11000-10400 aBP respectively correspond to the Oldest Dryas, Older Dryas and Younger Dryas events, whereas the two warm periods between them, 12000-13000 and 11600-11000 aBP, respectively correspond to Boiling and Allerod periods. The temperature increased abruptly after the Younger Dryas event, and then the climate gradually turned to be warm and wet from warm and semiarid. In the Holocene, the largest amplitude of cold event that occurred at ca. 8200 aBP is quite prominent. The Holocene climatic optimum culminated at 6700 aBP. After 2100 aBP, the climate tended to be cold and dry, keeping on up to now. Palaeoclimatic evolution and events of

关键词： Qinghai Lake pollen Lateglacial paleoclimate and paleoenvironment.

Risk Factors of Chronic Kidney Disease in Chronic Hepatitis B:A Hospital-based Case-control Study from China

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Journal of Clinical and Translational Hepatology 2022年第2期10卷 238-246页

作者： Yunqi Liu Ximei Wang Fuping Xu Dengren Li Huimin yang Nan Sun Yu-Chen Fan xiangdong yang Department of Nephropathy Qilu Hospital of Shandong UniversityJinanShandongChina Department of Nephropathy Binzhou Medical University HospitalBinzhouShandongChina Department of Nephrology The First Hospital of TianshuiTianshuiGansuChina Neurology Department Zibo Central HospitalShandong UniversityZiboShandongChina De-partment of General Practice Qilu Hospital of Shandong UniversityJinanShandongChina Laboratory of Basic Medical Sciences Qilu Hospital of Shandong UniversityJinanShandongChina Department of Hepatology Qilu Hospital of Shan-dong UniversityJinanShandongChina

Background and Aims:Chronic kidney disease(CKD)usually occurs during the chronic infection of hepatitis B virus(HBV).However,the risk factors of CKD in an HBV population have not been completely *** present study aimed to investigate the risk factors of CKD in chronic HBV infection using a hospital based cross-sectional study in the northern area of ***:During January 2013 to December 2017,a total of 94 patients with CKD complicated by chronic HBV infection were consecutively enrolled in the study,as well as 548 age-and sex-matched hepatitis B patients without CKD who were enrolled as *** and multivariate regression analyses were used to determine the effects of each variable after adjusting for cofounding ***:Multivariate analysis showed that HBeAg-positive status(odds ratio[OR]=2.099,95%CI 1.128-3.907),dyslipidemia(OR:3.025,95%CI 1.747-5.239),and hypertension(OR:12.523,95%CI 6.283-24.958)were independently associ-ated with the incidence of CKD,while duration of HBV in-fection(≥240 months)(OR:0.401,95%CI 0.179-0.894),Log10 HBsAg(OR:0.514,95%CI 0.336-0.786),and coro-nary heart disease(OR:0.078,95%CI 0.008-0.768)were protective factors for the incidence of *** of HBV infection,Log10 HBsAg,HBeAg-positive status and dyslipidemia remained the risk factors for CKD after adjusting for diabetes mellitus,hypertension,and coronary heart ***:Duration of HBV infection,Log10 HB-sAg,HBeAg-positive status and dyslipidemia contributed to the incidence of CKD during chronic HBV infection in a Chinese population.

关键词： Chronic kidney disease Hepatitis B virus Risk factors Cross-sec-tional study Case-control study

Improved Non-Sieving Quadratic Sieve

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Wuhan University Journal of Natural Sciences 2007年第1期12卷 67-70页

作者： HUANG Qingfeng LI Zhitang LIN Huaiqing yang xiangdong Network and Computer Center Huazhong Universityof Science and Technology Wuhan 430074Hubei China College of Electronic Engineering Naval Universityof Engineering Wuhan 430033 Hubei China

In this paper, we give about prime numbers and Blum two theorems and one guess *** prove the two theorems about Blum *** the guess with the primitive non-sieving quadratic sieve,we proposed a improved non-sieving quadratic sieve（INQS）.In INQS,we not only reduce the times of squares and modulo n, but also imply another important conclusion,that is,we don＇t need to find the greatest common divisor of two integers as we do in *** some examples,we compare it with the primitive non-sieving quadratic sieve（PNQS）. It＇s faster to factor a integer by using improved non-sieving quadratic sieve than the primitive one.

关键词： primitive non-sieving quardratic sieve INQS ecllipse curve