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Co-evolution of plant LTR-retrotransposons and their host genomes

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Protein & Cell 2013年第7期4卷 493-501页

作者： meixia zhao Jianxin Ma Department of Agronomy Purdue UniversityWest LafayetteIN 47907USA College of Life Sciences Qingdao Agricultural UniversityQingdao 266109China

Transposable elements(TEs),particularly,long terminal repeat retrotransposons(LTR-RTs),are the most abun-dant DNA components in all plant species that have been investigated,and are largely responsible for plant genome size *** plant genomes have experi-enced periodic proliferation and/or recent burst of LTR-retrotransposons,the majority of LTR-RTs are inactivated by DNA methylation and small RNA-mediated silencing mechanisms,and/or were deleted/truncated by unequal homologous recombination and illegitimate recombina-tion,as suppression mechanisms that counteract genome expansion caused by LTR-RT amplifi ***-RT DNA is generally enriched in pericentromeric regions of the host genomes,which appears to be the outcomes of pref-erential insertions of LTR-RTs in these regions and low effectiveness of selection that purges LTR-RT DNA from these regions relative to chromosomal *** functions of various TEs in their host genomes remain blurry;nevertheless,LTR-RTs have been recognized to play important roles in maintaining chromatin structures and centromere functions and regulation of gene expres-sions in their host genomes.

关键词： LTR-retrotransposons recombination evolu-tion epigenetic regulation plants

Sister-city Ties and Chinese Outward Foreign Direct Investment:A Spatial Econometric Analysis

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China & World Economy 2024年第1期32卷 231-258页

作者： Youxing Huang meixia Dong Yanping zhao School of Economics Ocean University of ChinaChina School of Economics and Marine Development Studies Institute Ocean University of ChinaChina

This paper employs dynamic spatial econometric methods to analyze the impact of the sister-city relationship on Chinese outward foreign direct investment(OFDI)using a linked country-level dataset from 2003 to *** results show strong and robust evidence that the sister-city relationship has been a crucial OFDI location determinant in host countries and their ***,the sister-city tie between China and the host country has stimulated Chinese OFDI in host ***,Chinese OFDI in host countries would be reduced if China concluded sister-city ties with their neighbors to which we refer as the neighboring *** mechanism tests show that sister cities have promoted OFDI in host countries via four channels:reducing political risk,decreasing information asymmetry,narrowing institutional distance,and mitigating cultural *** tendency for sister-city links to promote OFDI has varied substantially depending on OFDI entry modes(i.e.,greenfield or cross-border mergers and acquisitions),motivation(i.e.,resource-,market-,technology-,or efficiency-oriented OFDI),and Sino–foreign geographical relationships(i.e.,Belt and Road Initiative countries or other countries).

关键词： foreign direct investment location choice sister city spatial econometrics

Effects of herbicide butachlor application on the growth of periphytic biofilms and nitrogen loss in paddy systems

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Pedosphere 2024年第1期34卷 211-221页

作者： Yanhui zhao Mingjun LEI Liandong JING Fan XIA meixia YAN Jiantong LIU Yonghong WU Yunli WU Chenxi WU Ecology and Environment Monitoring and Scientific Research Center Yangtze Basin Ecology and Environment AdministrationMinistry of Ecological and EnvironmentWuhan 430010China College of Chemistry and Environmental Protection Engineering Southwest Minzu UniversityChengdu 610041China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The application of butachlor as an herbicide in paddy fields is widely practiced,aiming to increase rice yield by directly or indirectly influencing the paddy *** biofilms,which form at the soil-water interface in paddy fields,are complex bioaggregates that play an important role in nitrogen (N) *** objective of this study was to investigate the effect of butachlor on periphytic biofilm growth and N cycling under both light and dark conditions in the *** results revealed that butachlor application hindered the growth of periphytic biofilms and led to the dominance of Cyanobacteria as the primary prokaryotes,while inhibiting the development of eukaryotic ***,the application of butachlor reduced the richness and diversity of prokaryotes,but increased those of eukaryotes in periphytic *** light treatments exhibited higher total N loss because light favored periphytic biofilm growth and enhanced ammonium (NH_(4)^(+)) assimilation and ***,butachlor application resulted in the increased retention of NH_(4)^(+)-N and nitrate (NO_(3)^(-))-N and an increase in N loss via *** abundances of functional genes encoding enzymes such as ammonia monooxygenase,nitrite reductase,and nitrous oxide reductase were increased by butachlor application,favoring nitrification and denitrification ***,the results suggest that butachlor application leads to an increase in total N loss mainly through denitrification in paddy systems,particularly in the presence of periphytic ***,the results may provide valuable insights into the changes in periphytic biofilm growth and N cycling induced by butachlor,and future studies can further explore the potential implications of these changes in paddy soils.

关键词： ammonia-oxidizing bacteria amoA denitrification denitrifying bacteria nirK nitrification nitrogen cycling nosZ volatilization

New Genesis of Natural Coke around Magmatic Intrusion at the Shitai Coalmine of Huaibei City, North China

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Acta Geologica Sinica(English Edition) 2019年第4期93卷 1158-1159页

作者： zhao meixia AN Yanfei WANG Mina DING Min Chunkit LAI Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Innovation Academy of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510301China School of Resource and Environment Engineering Anhui UniversityHefei 230601China Faculty of Science University of Brunei DarussalamGadong BE1410Brunei Darussalam Centre for Excellence in Ore Deposits(CODES) University of TasmaniaHobart 7001Australia

Objective Studies on components of natural coke formed by the intrusion of sills into coals have attracted much attention,not only because the pyrolytic carbon in natural coke are associated with the magmatic events.

关键词： image New North

Two centuries-long records of skeletal calcification in massive Porites colonies from Meiji Reef in the southern South China Sea and its responses to atmospheric CO_2 and seawater temperature

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Science China Earth Sciences 2012年第1期55卷 1-12页

作者： SHI Qi YU KeFu CHEN TianRan ZHANG HuiLing zhao meixia YAN HongQiang Key Laboratory of Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China

Rising atmospheric CO2 and warming of the global climate that have occurred since the industrial revolution are regarded as fatal threats to coral reefs. We analyzed the skeletal calcification rate of 14 massive Porites corals from the Meiji Reef in the southern South China Sea through X-ray photography of coral skeletons. A general pattern of change in coral skeletal calcification was determined. The change pattern of coral calcification on the Meiji Reef over the past two centuries can be divided into five periods: calcification increase in 1770–1830, 1870–1920, and 1980–2000 and calcification decline in 1830–1870 and 1920–1980. Over the past two centuries, the largest increase in calcification was 4.5%, occurring in 1770–1830, whereas the largest decline in calcification was 6.2%, occurring in 1920–1980. Coral calcification slightly increased in the recent 20 years (1980–2000). The response relationship of coral calcification to atmospheric CO2 and sea surface temperature (SST) shows that calcification was not correlated with atmospheric CO2 but responded nonlinearly to SST with maxima at ∼27.2°C in 1900–2000. On the Meiji Reef, increasing atmospheric CO2 had a negligible effect on coral growth in the past century. However, rising SST improved coral growth in the early and middle 20th century, and restricted coral growth in the recent 20 years.

关键词：大气二氧化碳浓度中国海钙化骨骼海水温度殖民地微孔反应

Interspecies and spatial diversity in the symbiotic zooxanthellae density in corals from northern South China Sea and its relationship to coral reef bleaching

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Chinese Science Bulletin 2008年第2期53卷 295-303页

作者： LI Shu YU KeFu SHI Qi CHEN TianRan zhao meixia zhao JianXin CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Radiogenic Isotope Laboratory Centre for Microscopy & Microanalysis The University of Queensland QId 4072 Australia

珊瑚礁石漂白被共生 zooxanthellae， zooxanthellae 色素沉着的损失，或两个的逐出通常描绘。我们收集了分别地，在海南岛的 Sanya 和广东省的 Daya 海湾从 Luhuitou 和 Xiaodonghai 包括礁石大楼珊瑚的 21 个类的 39 种类的 128 件样... 详细信息

珊瑚礁石漂白被共生 zooxanthellae， zooxanthellae 色素沉着的损失，或两个的逐出通常描绘。我们收集了分别地，在海南岛的 Sanya 和广东省的 Daya 海湾从 Luhuitou 和 Xiaodonghai 包括礁石大楼珊瑚的 21 个类的 39 种类的 128 件样品并且分析了共生 zooxanthellae 人口密度。结果显示出那：( 1 )共生 zooxanthella 密度从 0.67x10 ( 6 )变化，显示 8.48x10 ( 6 )房间/厘米( 2 )重要内部种可变性，与通常相对有更少的 zooxanthellae 的分支珊瑚(从 0.67x10 ( 6 ) 到 2.47x10 ( 6 )房间/厘米( 2 ))比巨大的种类(从 1.0x10 ( 6 )到 8.48x10 ( 6 )房间/厘米( 2 ))；(2 ) 在 4 m 水深度以内住在的珊瑚比那些生活在底部有共生 zooxanthellae 的高水平(类似于 7 m 深度) 礁石区域；(3 ) 在在从相对高的纬度 Daya 海湾的珊瑚之间的 zooxanthellae 密度没有可辨别的差别(类似于 22 度 N ) 并且那些从相对低的纬度 Sanya (类似于 18 度 N ) 在可比较的海表面温度(SST ) ；(4 ) 在里面部分 -- 漂白珊瑚， zooxanthellae 的密度显示出下列顺序：看似健康的部分 > 漂白半的部分 > 漂白部分。基于上述结果，我们建议(1 ) 分叉之间的 zooxanthellae 密度差别和巨大的珊瑚种类是分叉的珊瑚对比巨大的珊瑚漂白更脆弱的主要原因。例如，共生 zooxanthellae 层次在分叉的 Acropora 和 Pocillopora 珊瑚并且这样是低的这些珊瑚更产生漂白和死亡；(2 ) 共生 zooxanthellae 密度能被环境条件也影响，例如沉积负担，潜水相关的混浊，和水产业相关的硝酸盐和磷酸盐输入，并且他们的增加可以在珊瑚减少共生 zooxanthellae 密度。

关键词：珊瑚礁漂白虫黄藻密度间种多样性空间多样性

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深井矩形巷道围岩应力分布规律及支护优化

采矿与岩层控制工程学报 2023年第6期5卷 39-48页

作者：杨宁赵美霞黄玉兵江苏建筑职业技术学院建筑建造学院江苏徐州221116 江苏建筑节能与建造技术协同创新中心江苏徐州221116 中国矿业大学(北京)深部岩土力学与地下工程国家重点实验室北京100083

针对巷道矩形断面结构易出现应力集中的现象,对巷道稳定性进行分析并针对性的提出支护优化方案。以赵楼煤矿5302工作面轨道巷为研究背景,基于复变函数理论建立了矩形巷道围岩应力分析模型,分析了不同埋深、不同宽高比、不同围岩力学参... 详细信息

针对巷道矩形断面结构易出现应力集中的现象,对巷道稳定性进行分析并针对性的提出支护优化方案。以赵楼煤矿5302工作面轨道巷为研究背景,基于复变函数理论建立了矩形巷道围岩应力分析模型,分析了不同埋深、不同宽高比、不同围岩力学参数下围岩的应力分布特征,提出了通过锚杆加强顶板、注浆加固巷帮的优化方案,并进行了FLAC^(3D)数值模拟验证和现场试验。结果表明:所提出的优化方案能有效改善破碎围岩的力学性能,提高巷道围岩的自承载能力,相较于原方案,巷帮平均变形量降低了32.9%,控制效果显著。

关键词：矩形巷道复变函数理论支护优化数值模拟

New fossil caddisfly from Middle Jurassic of Daohugou,Inner Mongolia,China(Trichoptera:Philopotamidae)

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Progress in Natural Science:Materials International 2009年第10期19卷 1427-1431页

作者： meixia Wang,Yunyun zhao,Dong Ren College of Life Science,Capital Normal University,Beijing 100037,China College of Life Science Capital Normal University Beijing 100037 China

A new genus and new species,Juraphilopotamus lubricus *** ***.,from the Middle Jurassic Jiulongshan Formation of Daohugou,Inner Mongolia,China,is described and *** may be the first record of the family Philopotamidae in China,extending the geographic distribution of this family.A detailed description and illustration of the specimen along with a brief review of the fossil Philopotamidae are given.A proposal on dispersionandmigration of Philopotamidae and problems of the paleoenvironment of the Daohugou beds are discussed.

关键词： Insecta Juraphilopotamus Philopotamidae Middle Jurassic Biogeography

Twenty-five years of change in scleractinian coral communities of Daya Bay (northern South China Sea) and its response to the 2008 AD extreme cold climate event

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Chinese Science Bulletin 2009年第12期54卷 2107-2117页

作者： CHEN TianRan YU KeFu SHI Qi LI Shu Gilbert J. Price WANG Rong zhao meixia CHEN TeGu zhao JianXin CAS Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Radiogenic Isotope Laboratory Centre for Microscopy & Microanaiysis The University of Queensland Brisbane QLD 4072 Australia

世界范围的珊瑚礁石逐渐地正在变得并且有害地影响在之上由包括的许多因素，重要气候变化，例如全球温暖和增加的 El Nino 南部的摆动活动。通常，珊瑚礁石的坚持，在特别低纬度，部分地，海运被管理不超过集体死亡能在发生的批评限制(... 详细信息

世界范围的珊瑚礁石逐渐地正在变得并且有害地影响在之上由包括的许多因素，重要气候变化，例如全球温暖和增加的 El Nino 南部的摆动活动。通常，珊瑚礁石的坚持，在特别低纬度，部分地，海运被管理不超过集体死亡能在发生的批评限制(∼30 ° C ) 的表面温度。因此，它被想珊瑚那生活在高纬度(即，当前更凉爽的海表面温度) 将多半比珊瑚生活在对假设未来温度增加更有利作出回应低纬度(即，当前更温暖的海表面温度) 。因而，高纬度的珊瑚社区可以有潜力在面临潜在的未来时为许多珊瑚种类充当 refugia 的区域全球温暖。Daya 海湾(22 ° 3 1 ′22 ° 5 0 ′N ) ，北华南海，包含几个高纬度的 non-reefal 珊瑚社区并且在这个区域以内代表 scleractinian 珊瑚的最在北方的分布之一。显著地， Daya 海湾经历了在整个过去的 50 年的在空和海表面温度中的戏剧的温暖。在这篇论文，我们在 Daya 海湾珊瑚社区分析 25 年变化，把两个基于历史性的调查并且我们的最近 2006 2008 地区性的生态的调查。我们的结果建议与预言相反，在过去的 25 年期间在在 Daya 海湾以内的珊瑚盖子有重要衰落(即，在到在 2008 的 15.3% 仅仅珊瑚盖子的 1983/1984 的 76.6% 珊瑚盖子) 。如此的变化也在最丰富的珊瑚种类反映重要移动，从 Acropora pruinosa 到 Favites abdita。大多数现代珊瑚社区变得以前在 15 和 30 年之间建立了，相应于增加的冬季海表面温度的一个时期。然而，很少的殖民地变得在最后 15 年以内建立了，尽管有温暖的一个更强烈的时期。由考虑另外的因素，我们假设那直接人为的影响，而非气候的事件，限制了发展，并且驾驶了衰落，最后 15 年里的 Daya 海湾珊瑚社区。Daya 海湾也在过去的 50 年期间受到了偶尔的极端冷事件，与最近的发生在 2008 年初(13 年 1 月 13 日 2 月) 。在 2008 冷事件期间，最低空气温度到达仅仅 6.6 ° C，和吝啬的海表面温度 2 月秋天，包括在 12.3 ° C 的六连续的天 < 14 ° C。显著地，海表面温度在通常在 scleractinian 珊瑚社区导致集体死亡的假设批评更低的温度阀值(∼13 ° C ) 下面掉落。令人惊讶地，我们的珊瑚社区调查，以前进行了两个(2007 年 8 月) 并且在以后(2008 年 2 月下旬) 极端 2008 冷事件，证明 Daya 海湾珊瑚生态系统恰好被影响在之上在冷时期期间。那些观察建议 Daya 海湾 scleractinian 珊瑚社区开发了改编到低海表面温度。总的来说，我们的数据支持高纬度的珊瑚社区例如 Daya 海湾，有的假设在潜在的未来的来临为 scleractinian 珊瑚充当 refugia 的区域的潜力全球温暖。

关键词：极端气候事件珊瑚群落大亚湾中国海海洋表面温度 SEA 高纬度地区低纬度地区