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东海陆架盆地丽水-椒江凹陷灵峰组海相烃源岩发育主控因素及分布特征

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海洋地质前沿 2025年第2期41卷 21-29页

作者：李林致李婧婧廖计华郭刚王欣李峰中海油研究总院有限责任公司北京100028

东海陆架盆地丽水-椒江凹陷古新统烃源岩的研究主要集中在月桂峰组湖相烃源岩,而对于灵峰组海相优质烃源岩的形成条件与分布规律尚不明确。综合利用地质、地球化学和古生物等资料,在烃源岩有机地球化学特征分析的基础上,探讨了丽水-椒... 详细信息

东海陆架盆地丽水-椒江凹陷古新统烃源岩的研究主要集中在月桂峰组湖相烃源岩,而对于灵峰组海相优质烃源岩的形成条件与分布规律尚不明确。综合利用地质、地球化学和古生物等资料,在烃源岩有机地球化学特征分析的基础上,探讨了丽水-椒江凹陷灵峰组海相烃源岩发育的主控因素,并对烃源岩的形成模式和分布进行了探究。结果表明,丽水-椒江凹陷灵峰组发育中等—好级别的陆源海相烃源岩,内部不同洼陷具有较强的非均质性;烃源岩的发育受古生产力、陆源输入和水体条件等因素的综合影响。平面上,丽水-椒江凹陷灵峰组海相烃源岩的规模和质量与该区三角洲-滨浅海的沉积环境密切相关。三角洲前缘和近三角洲的浅海相带陆源有机质输入量大,在弱氧化—弱还原环境下发育高丰度烃源岩,是灵峰组好烃源岩发育的有利相带。

关键词：丽水-椒江凹陷灵峰组海相烃源岩主控因素陆源有机质输入

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北京市生态系统服务价值时空变化及其驱动力

生态学报 2025年第1期45卷 306-318页

作者：张剑飞阳文锐李晶晶沈守云马力陈亮中南林业科技大学长沙410004 北京市城市规划设计研究院北京100045 中国建筑工程第五工程局建筑设计院长沙430000 黑龙江省城市规划勘测设计研究院哈尔滨150040

人类活动主导的土地利用变化改变了生态系统的结构和功能,影响了生态系统服务水平。评估生态系统服务价值是合理配置自然资源和生态环境保护的重要基础。以北京市域为研究范围,基于2003年、2010年2022年三期遥感影像解译数据,采用当量... 详细信息

人类活动主导的土地利用变化改变了生态系统的结构和功能,影响了生态系统服务水平。评估生态系统服务价值是合理配置自然资源和生态环境保护的重要基础。以北京市域为研究范围,基于2003年、2010年2022年三期遥感影像解译数据,采用当量因子法、空间自相关分析等方法,分析了两轮城市总体规划以来,1km×1km网格下的全市生态系统服务价值的空间分布和变化特征,并利用地理探测器研究了生态系统服务价值空间异质性的驱动力因素。研究结果发现:(1)研究时段内全市生态系统服务价值变化特征与非建设用地组分变化相对应,出现了先下降后上升的趋势,其总量增加了109.46亿元,林地和水域的增加是生态系统服务价值提升的关键;(2)从生态系统服务四大类型的价值看,调节功能>支持功能>供给功能>文化功能,调节服务是北京市生态系统的主导功能;(3)从空间分布看,生态系统服务价值呈现西北高、东南低的空间格局,而且全市生态系统服务价值表现为正相关和空间聚集分布,局部表现为高⁃高、低⁃低集聚;生态系统服务价值热点地区主要集中于大型湿地水域,生态系统服务价值冷点分布范围在逐渐向市中心城区收缩;(4)生态系统服务价值空间异质性受到自然地理和社会经济的共同作用,其中气温的贡献最大,双因子间的耦合作用增强了对生态系统服务价值空间分布的解释力。研究揭示了城市土地利用变化过程中生态系统服务的时空变化规律及其驱动力。提出了提升生态系统服务价值的非建设用地管理建议,可为自然资源的可持续利用提供重要参考。

关键词：生态系统服务价值土地利用空间分析敏感性分析自然资源管理

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TRIM46对HDAC1泛素化和高糖诱导HRCECs通透性的影响及作用机制

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中华眼视光学与视觉科学杂志 2025年第2期27卷 96-103页

作者：许畅周峰张炜李晶晶湖北文理学院附属医院襄阳市中心医院眼科襄阳

目的: 研究人类三重基序蛋白46(TRIM46)对组蛋白去乙酰化酶1(HDAC1)泛素化和高糖(HG)诱导的人视网膜毛细血管内皮细胞(HRCECs)通透性的影响及作用机制。方法: 实验研究。2020年3月体外培养HRCECs后, 依据葡萄糖培养浓度分为正常组(5.5 m... 详细信息

目的: 研究人类三重基序蛋白46(TRIM46)对组蛋白去乙酰化酶1(HDAC1)泛素化和高糖(HG)诱导的人视网膜毛细血管内皮细胞(HRCECs)通透性的影响及作用机制。方法: 实验研究。2020年3月体外培养HRCECs后, 依据葡萄糖培养浓度分为正常组(5.5 mmol/L正常葡萄糖培养)、HG组(25.0 mmol/L高浓度葡萄糖培养)、阴性组(转染空质粒vector或shRNA)、oeTRIM46组(转染TRIM46过表达质粒)、shTRIM46组(转染TRIM46的RNAi序列以下调TRIM46表达)、oeTRIM46+vector组(共转染TRIM46过表达质粒和空质粒vector)、oeTRIM46+HDAC1组(共转染TRIM46过表达质粒和HDAC1过表达质粒)。蛋白免疫印迹分析(Western blot)和实时荧光定量PCR(qRT-PCR)分别检查血管内皮钙黏蛋白(VE-cadherin)、TRIM46、HDAC1等蛋白或TRIM46 mRNA表达;免疫共沉淀法测定HDAC1泛素化表达;跨内皮电阻(TER)检测单层细胞电阻(Ω×cm2);Transwell通透性实验观察HRCECs单层通透性。采用单因素方差分析或t检验比较各组间TRIM46表达、HRCECs单层通透性、HDAC1泛素化表达等数据的差异。结果: 与正常组相比, HG处理后可诱导HRCECs中TRIM46表达上调(t=7.06, P<0.001)和TER升高(t=8.13, P=0.001), 明显增加HRCECs通透性(t=12.03、6.57、12.38, P<0.05);oeTRIM46组上调TRIM46表达后, 在HG条件下, 单层HRCECs的TER和异硫氰酸荧光素葡聚糖FD-20通透性增加, 反之亦然(均P<0.05)。TRIM46过表达可促进HDAC1泛素化, 敲低则显示相反的效果, 在oeTRIM46组和HG组中, HDAC1泛素化较正常组均明显增加(均P<0.05);此外, 与阴性组相比, oeTRIM46组p-VE-cadherinTyr731表达水平、单层细胞TER以及FD-20荧光强度均明显增加, TRIM46表达下调后上述变化相反(均P<0.001), 而HDAC1表达上调后可改善TRIM46过表达对HRCECs通透性的影响(P<0.001)。结论: HG可诱导HRCECs中TRIM46表达水平升高, 而高水平TRIM46可促进HDAC1泛素化和降解, 并增加HRCECs通透性。

关键词：视网膜细胞人类三重基序蛋白46 组蛋白去乙酰化酶1泛素化通透性

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生态输水对台特玛湖生态改善情况分析评价

水土保持研究 2025年第2期32卷 316-320,330页

作者：张建国曹雪峰李晶晶黄河水利委员会黄河上中游管理局西安710021

[目的]评价台特玛湖生态输水后受影响区域的生态环境改善状况,为区域植被建设、遏制水土流失、修复湖泊生态等提供支撑。[方法]基于全国水土流失动态监测成果,对比分析台特玛湖生态输水前(1998年)和现状年(2022年)流域土地利用变化及对... 详细信息

[目的]评价台特玛湖生态输水后受影响区域的生态环境改善状况,为区域植被建设、遏制水土流失、修复湖泊生态等提供支撑。[方法]基于全国水土流失动态监测成果,对比分析台特玛湖生态输水前(1998年)和现状年(2022年)流域土地利用变化及对应的水土流失变化情况。[结果]与生态输水前相比,台特玛湖受水影响区沙地面积减少454.79 km^(2),减幅70.79%;植被面积增加了304.30 km^(2),增幅100.24%。植被覆盖度由生态输水前的14.83%增加到22.26%;台特玛湖生态输水影响区域水土流失面积减少437.51 km^(2),为254.60 km^(2),占土地总面积的25.18%,均为轻度侵蚀。水土流失面积减少437.51 km^(2)。[结论]生态输水后,台特玛湖生态环境明显好转,区域的土地利用由以沙地为主的单一结构向多样结构转变,植被覆盖度明显提升。

关键词：塔里木河台特玛湖水土流失动态变化生态输水

Exploring the linear and Nonlinear Causality Between Internet Big Data and Stock Markets

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Journal of Systems Science & Complexity 2020年第3期33卷 783-798页

作者： DONG Jichang DAI Wei li jingjing School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China School of Economics and Management Beihang UniversityBeijing 100191China

In the era of big data,stock markets are closely connected with Internet big data from diverse *** paper makes the first attempt to compare the linkage between stock markets and various Internet big data collected from search engines,public media and social *** achieve this purpose,a big data-based causality testing framework is proposed with three steps,i.e.,data crawling,data mining and causality *** the Shanghai Stock Exchange and Shenzhen Stock Exchange as targets for stock markets,web search data,news,and microblogs as samples of Internet big data,some interesting findings can be obtained.1)There is a strong bi-directional,linear and nonlinear Granger causality between stock markets and investors'web search behaviors due to some similar trends and uncertain factors.2)News sentiments from public media have Granger causality with stock markets in a bi-directional linear way,while microblog sentiments from social media have Granger causality with stock markets in a unidirectional linear way,running from stock markets to microblog sentiments.3)News sentiments can explain the changes in stock markets better than microblog sentiments due to their *** results of this paper might provide some valuable information for both stock market investors and modelers.

关键词： Granger causality test internet big data investors'sentiment stock markets web search behavior

Quasi-static and dynamical analyses of a thermoviscoelastic Timoshenko beam using the differential quadrature method

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Applied Mathematics and Mechanics(English Edition) 2019年第4期40卷 549-562页

作者： Qiang LYU jingjing li Nenghui ZHANG Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Department of Mechanics College of Sciences Shanghai University

The quasi-static and dynamic responses of a thermoviscoelastic Timoshenko beam subject to thermal loads are analyzed. First, based on the small geometric deformation assumption and Boltzmann constitutive relation, the governing equations for the beam are presented. Second, an extended differential quadrature method(DQM)in the spatial domain and a differential method in the temporal domain are combined to transform the integro-partial-differential governing equations into the ordinary differential equations. Third, the accuracy of the present discrete method is verified by elastic/viscoelastic examples, and the effects of thermal load parameters, material and geometrical parameters on the quasi-static and dynamic responses of the beam are discussed. Numerical results show that the thermal function parameter has a great effect on quasi-static and dynamic responses of the beam. Compared with the thermal relaxation time, the initial vibrational responses of the beam are more sensitive to the mechanical relaxation time of the thermoviscoelastic material.

关键词： Timoshenko beam thermoviscoelasticity thermal load dynamic response,differential quadrature method(DQM)

SURFACE STRESS PROPERTIES OF DNA-MICROCANTILEVER SYSTEMS

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Acta Mechanica Solida Sinica 2014年第2期27卷 122-128页

作者： Zouqing Tan Nenghui Zhang jingjing li Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Department of Mechanics College of Sciences Shanghai University

For the first time, the connection between surface stress and nanoscopic interac- tions of DNA adsorbed on microcantilever is established by combining Strey＇s mesoscopic liquid crystal theory and Stoney＇s formula. It is shown that surface stress depends not only on biomolec- ular interactions of DNA biofilm but also on mechanical properties of cantilever. Considering the correlativity between grafting density and chain length of DNA chain, we discuss the differences between DNA-microcantilever system and DNA solution system. The major theoretical achieve- ment of this model is to identify the main contributions to surface stress under different detection conditions. This provides guidelines for designing new biosensors with high sensitivity and improved reliability.

关键词： surface stress DNA hybridization microcantilever biosensor energy method biomolecular interaction

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Chinese Journal of Electronics 2017年第1期26卷 35-41页

作者： XIE Min li jingjing ZANG Yuechuan State Key Laboratory of Integrated Service Networks Xidian University

A related-key impossible differential attack on 24-round LBlock is constructed by using new 16-round related-key impossible differentials and adding 4rounds at the top and 4 rounds at the bottom of these 16-round related-key impossible differential paths. The data and time complexities are about 263chosen plaintexts and275.4224-round encryptions respectively.

关键词： LBlock lightweight block cipher Related-key impossible differential attack

Acute pathological changes of facial nucleus and expressions of postsynaptic density protein-95 following facial nerve injury of varying severity A semi-quantitative analysis

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Neural Regeneration Research 2008年第5期3卷 525-528页

作者： jingjing li Wenlong Luo Department of Otolaryngology-Head and Neck Surgery. The Second Affiliated Hospital Chongqing University of Medical SciencesChongqing 400010 China

BACKGROUND： Previous studies have demonstrated that postsynaptic density protein-95 （PSD-95） is widely distributed in the central nervous system and is related to the development of the CNS and sensory signal transmission as well as acute or chronic nerve cell death following ischemic brain injury. OBJECTIVE： To semi-quantitatively determine the pathological changes of apoptotic facial neurons and the expression of PSD-95 in the facial nucleus following facial nerve injury of varying extents using immunohistochemical staining methods. DESIGN, TIME AND SETTING： Randomized, controlled animal experiments were performed in the Ultrasonic Institute of the Second Affiliated Hospital of Chongqing University of Medical Sciences from September to December 2007. MATERIALS： Sixty-five healthy, adult, Sprague-Dawley （SD） rats, both male and female, were used for this study. Rabbit anti-rat PSD-95 polyclonal antibody was purchased from Beijing Biosynthesis Biotechnology Co., Ltd. METHODS： SD rats were randomly assigned into a control group with five rats and three injured groups with 20 rats per group. Exposure, clamp and cut for bilateral facial nerve trunks were performed in the rats of the injury groups, and no injury was inflicted on the rats of the control group. MAIN OUTCOME MEASURES; The brainstems of all the rats were excised on days 1, 3, 7, and 14 post injury, and then the facial nuclei were stained with hematoxylin-eosin to observe any pathological changes due to apoptosis in facial neurons. PSD-95 expression in facial nuclei was detected by immunohistochemistry and the number of PSD-95 positive cells was counted under a light microscope. RESULTS： The expression of PSD-95 in the facial nucleus and morphology of the facial neuron within the exposure group had no obvious changes at various points in time tested （P 〉 0.05）. However, the expressions of PSD-95 in the facial nucleus of the clamp group and cut group increased on day 1 post injury （P 〈 0.05）, and showed furth

关键词： facial nerve injury facial nucleus postsynaptic density protein-95 rats