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Dynamic global analysis of transcription reveals the role of mi RNAs in synergistic stabilization of gene expression

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Science Bulletin 2020年第24期65卷 2130-2140,M0006页

作者： Fuqiang Ma Guang-An Lu Qingjian Chen Yongsen Ruan Xin li Xuemei Lu chunyan li School of life Sciences Sun Yat-sen University.Guangzhou 510275China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of Medicine and Engineeringand Key Laboratory of Big Data-Based Precision Medicine(Ministry of Industry and Information Technology)Beihang UniversityBeijing 100191China State Key Laboratory of Genetic Resources and Evolution&CAS Center for Excellence in Animal Evolution and Genetics Kunming Institute of ZoologyChinese Academy of SciencesKunming 650223China State Key Laboratory of Molecular Developmental Biology Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Genomic and Precision Medicine Beijing Institute of GenomicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Buffering exogenous perturbation is crucial to maintain transcriptional homeostasis during *** mi RNAs have been speculated to play a role in stability maintenance, previous studies seeking to check this conjecture focused on measurements of transcript levels at steady state or involved individual mi RNA targets. We measured whole-genome expression dynamics by introducing a transient perturbation and establishing a perturbation and recovery system in Drosophila larvae. We inhibited all transcription and assayed transcriptomes at several time points during recovery from inhibition. We performed these experiments in the wild type and mi RNA-deficient genetic backgrounds. Consistent with theories about mi RNAs’ function in stabilizing the transcriptome, we find that attenuating mi RNA expression leads to weak impairment in degradation of targets but strong destabilization of target genes when transcription is re-activated. We further fitted a model that captures the essential aspects of transcription dynamics in our experiments and found that the mi RNA target transcripts uniformly overshoot the original steady state as they recover from a general inhibition of transcription if global mi RNA levels are reduced. Collectively, our results provide experimental evidence for the idea that mi RNAs act cumulatively to stabilize the transcriptional regulatory network. We therefore found a promising approach to assess the effect of these molecules on transcription dynamics.

关键词： miRNAs Transcriptome Perturbation Stability Synergistic effects

Three-dimensional structure of a low salinity tongue in the southern Taiwan Strait observed in the summer of 2005

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Acta Oceanologica Sinica 2009年第4期28卷 1-7页

作者： HONG Huasheng ZHENG Quanan HU Jianyu CHEN Zhaozhang li chunyan JIANG Yuwu WAN Zhenwen State Key Laboratory of Marine Environmental Science College of Oceanography and Environmental Science Xiamen University Xiamen 361005 China Department of Atmospheric and Oceanic Science University of Maryland College Park MD 20742 USA Department of Oceanography and Coastal Sciences Coastal Sciences School of the Coast and Environment Louisiana State University Baton Rouge LA 70803 USA

Cruise observations with CTD （conductivity-temperature-depth） profiler were carried out in the southern Taiwan Strait in the summer of 2005. Using the cruise data, two-dimensional maps of salinity and temperature distributions at depths of 5, 10, 15, 20, and 30 m were generated. The maps show a low salinity tongue sandwiched by low temperature and high salinity waters on the shallow water side and high temperature and high salinity waters on the deep water side. The further analysis indicates that the low salinity water has a nature of river-diluted water. A possible source of the diluted water is the Zhujiang （Pearl） Estuary. Meanwhile, the summer monsoon is judged as a possible driving force for this northeastward jet-like current. The coastal upwelling and the South China Sea Warm Current confine the low salinity water to flow along the central line of the strait. Previous investigations and a numerical model are used to verify that the upstream of the low salinity current is the Zhujiang Estuary. Thus, the low salinity tongue is produced by four major elements： Zhujinag Estuary diluted water, monsoon wind driving, coastal upwelling and South China Sea Warm Current modifications.

关键词： Taiwan Strait low salinity tongue river diluted water cruise measurement

基于Q-ARMA的电子式电压互感器误差状态预测

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中国科学：技术科学 2018年第12期48卷 1401-1412页

作者：李振华李春燕张竹三峡大学电气与新能源学院宜昌443002 华中科技大学电气与电子工程学院武汉430074

电子式电压互感器作为传统电磁式互感器的理想替代品,被大量应用于智能电网中,目前存在的主要问题是误差的长期稳定性较差,对电网的安全稳定和经济运行造成了一定的隐患.现用的定期离线检测的方式不利于及时发现电子式电压互感器误差状... 详细信息

电子式电压互感器作为传统电磁式互感器的理想替代品,被大量应用于智能电网中,目前存在的主要问题是误差的长期稳定性较差,对电网的安全稳定和经济运行造成了一定的隐患.现用的定期离线检测的方式不利于及时发现电子式电压互感器误差状态的变化情况,提出了一种基于Q-ARMA的误差状态预测方法,采集三相电子式电压互感器的测量数据,利用主元分析的方法将电子式电压互感器的误差状态映射为电气物理关系约束下的Q统计量,消除了电网波动对其误差状态预测的影响.建立Q统计量的ARMA预测模型,实验表明该方法可准确预测电子式电压互感器的误差状态变化趋势.

关键词：电子式电压互感器误差状态预测 Q统计量 ARMA

缘起·价值·框架:中华民族共同体形象图像叙事的三维探赜

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中州学刊 2023年第11期 169-176页

作者：李春燕中南民族大学马克思主义学院湖北武汉430074

新媒体时代,探究中华民族共同体形象图像叙事的逻辑缘起、价值诉求和叙事框架,可为铸牢中华民族共同体意识提供叙事支撑。从发生学角度看,文化的视觉转向、社会日常生活的图像化、新兴媒介技术的发展,构成了中华民族共同体形象图像叙事... 详细信息

新媒体时代,探究中华民族共同体形象图像叙事的逻辑缘起、价值诉求和叙事框架,可为铸牢中华民族共同体意识提供叙事支撑。从发生学角度看,文化的视觉转向、社会日常生活的图像化、新兴媒介技术的发展,构成了中华民族共同体形象图像叙事缘起的三大逻辑支点。中华民族共同体形象的图像叙事可通过再现历史记忆、唤醒政治情感、勾连归属性认同,实现涵养中华民族共同体集体潜意识、塑造中华民族共同体情感认知、增进中华民族共同体认同的价值旨归。图像叙事最终需要依托叙事框架帮助受众理解意义。其叙事框架通过图像生产的主体互动、图像文本的表征修辞、图像接受的意义询唤三个环节,完成主体性叙事、劝服性叙事、意识形态叙事,为中华民族共同体形象提供了一条视觉修辞路径。

关键词：中华民族共同体形象图像叙事发生逻辑叙事价值叙事框架

Inter‑Skeleton Conductive Routes Tuning Multifunctional Conductive Foam for Electromagnetic Interference Shielding,Sensing and Thermal Management

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Nano-Micro Letters 2025年第3期17卷 19-36页

作者： Xufeng li chunyan Chen Zhenyang li Peng Yi Haihan Zou Gao Deng Ming Fang Junzhe He Xin Sun Ronghai Yu Jianglan Shui Caofeng Pan Xiaofang liu School of Materials Science and Engineering Beihang UniversityBeijing 100191People’s Republic of China Institute of Atomic Manufacturing Beihang UniversityBeijing 100191People’s Republic of China Tianmushan Laboratory Xixi Octagon CityYuhang DistrictHangzhou 310023People’s Republic of China Science and Technology On Electromagnetic Scattering Laboratory Beijing Institute of Environmental FeaturesBeijing 100854People’s Republic of China

Conductive polymer foam(CPF)with excellent compressibility and variable resistance has promising applications in electromagnetic interference(EMI)shielding and other integrated functions for wearable ***,its insufficient change amplitude of resistance with compressive strain generally leads to a degradation of shielding performance during ***,an innovative loading strategy of conductive materials on polymer foam is proposed to significantly increase the contact probability and contact area of conductive components under *** inter-skeleton conductive films are constructed by loading alginate-decorated magnetic liquid metal on the polymethacrylate films hanged between the foam skeleton(denoted as AMLM-PM foam).Traditional point contact between conductive skeletons under compression is upgraded to planar contact between conductive ***,the resistance change of AMLM-PM reaches four orders of magnitude under ***,the inter-skeleton conductive films can improve the mechanical strength of foam,prevent the leakage of liquid metal and increase the scattering area of EM ***-PM foam has strain-adaptive EMI shielding performance and shows compression-enhanced shielding effectiveness,solving the problem of traditional CPFs upon *** upgrade of resistance response also enables foam to achieve sensitive pressure sensing over a wide pressure range and compression-regulated Joule heating function.

关键词： Inter-skeleton conductive films Conductive polymer foam liquid metal Electromagnetic interference shielding

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汉语语音构词及其语义、语法制约

华中师范大学学报（人文社会科学版） 2020年第2期59卷 115-121页

作者：李春艳天津大学外国语言与文学学院中文系天津300354

学界通常以是否由单一语素构成为判定标准,将词分为单纯词和合成词,语法构词产生合成词,语音构词产生单纯词。但有些受语音构词制约产生的联绵词,并非是单一语素。本文从语词产生的制约因素、构词的历时发展、语音语义的双重联想关系以... 详细信息

学界通常以是否由单一语素构成为判定标准,将词分为单纯词和合成词,语法构词产生合成词,语音构词产生单纯词。但有些受语音构词制约产生的联绵词,并非是单一语素。本文从语词产生的制约因素、构词的历时发展、语音语义的双重联想关系以及汉藏语系语音构词的特征等方面论析,说明语词的产生会受到语音、语义和语法的制约,在不同语词中语音、语义和语法制约力并不平衡,语音构词中也有语法和语义的参与。

关键词：语音构词语法制约语义制约

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重叠的韵律和谐与语音拗口模式研究

复旦学报（社会科学版） 2020年第4期62卷 43-49,74页

作者：李春艳天津大学外国语言与文学学院天津300354

汉语中重叠常被用于诗歌和绕口令中,在诗歌中重叠的运用会产生韵律和谐与音乐美感,而在绕口令中所形成的却是语音拗口。二者虽都采用重叠形成但语音效果却截然相反。论文从重叠呈现的规律性、重叠的量度机制、重叠成分和非重叠成分的语... 详细信息

汉语中重叠常被用于诗歌和绕口令中,在诗歌中重叠的运用会产生韵律和谐与音乐美感,而在绕口令中所形成的却是语音拗口。二者虽都采用重叠形成但语音效果却截然相反。论文从重叠呈现的规律性、重叠的量度机制、重叠成分和非重叠成分的语音搭配三个方面分析研究发现:有规律重复出现的重叠产生韵律和谐,无规律重复出现的重叠产生语音拗口;重叠的量度中,诗歌一句中有一处双声或叠韵,会增强诗歌的音乐性,若四字或五字声同或韵同会产生拗口诗,绕口令就是通过多个声同或韵同字的连续使用产生拗口;通过对四音格词的分析发现虽然四字声同或韵同,若利用其他语音成分的差异性进行巧妙的规律搭配,反而会形成较高的语音和谐和乐音性。

关键词：重叠韵律和谐语音拗口

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中学地理“大概念”下的单元教学设计

课程．教材．教法 2020年第9期40卷 96-101页

作者：李春艳北京教育学院数学与科学教育学院北京100044

“大概念”和“单元教学”是当下学科核心素养落地的两个关键词。大概念是相对概念更是思想方法,它具有与具体概念所不同的四个特点:它是揭示概念关系并阐述观点的陈述句;能跨领域统摄非连续内容;具有横断性,能跨时间、文化和情境迁移;... 详细信息

“大概念”和“单元教学”是当下学科核心素养落地的两个关键词。大概念是相对概念更是思想方法,它具有与具体概念所不同的四个特点:它是揭示概念关系并阐述观点的陈述句;能跨领域统摄非连续内容;具有横断性,能跨时间、文化和情境迁移;可以贯通进阶发展。大概念下的单元教学设计要通过确定单元组织核心、梳理单元大概念体系及确定教学设计思维展开路径来完成,它突破了自然单元和主题单元的局限。

关键词：单元教学设计大概念地理教学层级式知识结构

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反凸极永磁同步电机弱磁特性分析

电工技术学报 2019年第S2期34卷 474-483页

作者：李春艳王豫孟涛黑龙江大学机电工程学院

提出一种新型反凸极永磁同步电机,利用转子永磁体分段磁桥和调整铁心为直轴磁通提供路径从而实现直轴电感大于交轴电感。低速运行时采取正值的直轴电流控制产生正值的磁阻转矩,同时正向电流可有效提高永磁体的工作点。高转速运行电机可... 详细信息

提出一种新型反凸极永磁同步电机,利用转子永磁体分段磁桥和调整铁心为直轴磁通提供路径从而实现直轴电感大于交轴电感。低速运行时采取正值的直轴电流控制产生正值的磁阻转矩,同时正向电流可有效提高永磁体的工作点。高转速运行电机可以使用相对较小的直轴弱磁电流来削弱气隙磁通,实现弱磁升速,有效扩大电机的弱磁范围。建立新型反凸极永磁同步电机的直交轴磁路模型,分析新型反凸极永磁同步电机电磁转矩特性和弱磁特性,并进行有限元分析。理论分析结果与仿真计算分析结果相吻合,验证了反凸极永磁同步电机弱磁的有效性和可行性。

关键词：反凸极永磁同步电机弱磁特性直轴和交轴电感调整铁心