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The unimodal latitudinal pattern of K,Ca and Mg concentration and its potential drivers in forest foliage in eastern China

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Forest Ecosystems 2024年第3期11卷 318-328页

作者： Zhijuan Shi Sining Liu yahan chen Dongdong Ding Wenxuan Han Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing100193China Forestry Ecological Engineering in the Upper Reaches of the Yangtze River Key Laboratory of Sichuan Province&National Forestry and Grassland Administration Key Laboratory of Forest Resources Conservation and Ecological Safety on the Upper Reaches of the Yangtze River College of ForestrySichuan Agricultural UniversityChengdu611130China Institute of Botany Chinese Academy of SciencesBeijing100093China

Potassium(K),calcium(Ca),and magnesium(Mg)are essential elements with important physiological functions in *** studies showed that leaf K,Ca,and Mg concentrations generally increase with increasing ***,recent meta-analyses suggested the possibility of a unimodal pattern in the concentrations of these elements along latitudinal *** authenticity of this unimodal latitudinal pattern,however,requires validation through large-scale field experimental data,and exploration of the underlying mechanisms if the pattern is ***,we collected leaves of common species of woody plants from 19 montane forests in the north-south transect of eastern China,including 322 species from 160 genera,67 families;and then determined leaf K,Ca,and Mg concentrations to explore their latitudinal patterns and driving *** results support unimodal latitudinal patterns for all three elements in woody plants across eastern China,with peak values at latitude 36.5±1.0°*** shift of plant-functional-type compositions from evergreen broadleaves to deciduous broadleaves and to conifers along this latitudinal span was the key factor contributing to these *** factors,mainly temperature,and to a lesser extent solar radiation and precipitation,were the main environmental *** factors,by altering the composition of plant communities and regulating plant physiological activities,influence the latitudinal patterns of plant nutrient *** findings also suggest that high leaf K,Ca,and Mg concentrations may represent an adaptive strategy for plants to withstand water stress,which might be used to predict plant nutrient responses to climate changes at large scales,and broaden the understanding of biogeochemical cycling of K,Ca,and Mg.

关键词： Potassium Calcium Magnesium Mid-latitudes Latitudinal pattern Plant functional type Water stress Woody plant

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艺术生产与剧院生存:商业剧院的运作机制研究

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四川戏剧 2024年第3期 134-138页

作者：陈雅涵王忠澳门城市大学人文社会科学学院中国澳门

剧院是戏曲戏剧等表演艺术演出的空间载体,承载着艺术创作及文化传承等重要功能。但是如今剧院“重建设、轻管理”及“建得起、养不起”的现象普遍存在,暴露了现有经营模式的不可持续性。本文以实行市场化运营的广州大剧院为例,采用行... 详细信息

剧院是戏曲戏剧等表演艺术演出的空间载体,承载着艺术创作及文化传承等重要功能。但是如今剧院“重建设、轻管理”及“建得起、养不起”的现象普遍存在,暴露了现有经营模式的不可持续性。本文以实行市场化运营的广州大剧院为例,采用行动者网络理论作为理论基础及分析方法,剖析剧院管理模式及市场化运营可操作性的问题。研究发现,以剧院管理人员为核心,串连政府、文艺从业者、观众、剧院建筑、商业合作公司及游客等主体可构成有效的行动者网络。联结多方主体构建利益联盟、关注空间生产、有效利用数字技术及培养管理人才是剧院实现自给自足市场化运营的关键。通过归纳总结广州大剧院的运作机制,本文将为广大商业剧院的可持续发展提供参考、为戏剧戏曲等表演艺术的演出与传承提供空间。

关键词：行动者网络理论商业剧院运作机制表演艺术可持续发展

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大语言模型在学术研究中的价值、风险及其规避

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社会科学战线 2024年第1期 149-155页

作者：苏君阳陈亚涵刘腾宇北京师范大学教育管理学院北京100875 北京通用人工智能研究院北京100080

人工智能时代下,以大语言模型为代表的生成式人工智能技术引发了多领域的范式革命,探索其在学术研究中的应用价值与风险规避具有必要性。大语言模型本质是字词从语言空间向语义空间的转换模型,具有同构性、统一性与稳定性的特征。大语... 详细信息

人工智能时代下,以大语言模型为代表的生成式人工智能技术引发了多领域的范式革命,探索其在学术研究中的应用价值与风险规避具有必要性。大语言模型本质是字词从语言空间向语义空间的转换模型,具有同构性、统一性与稳定性的特征。大语言模型在学术研究中的价值主要体现在原创性、知识管理与应用认同三个维度,提供了跨学科学术创新、学术体系发展与提升学术研究影响力的价值。大语言模型存在的结构性与能动性局限主要表现为方法模糊、责任模糊、评价模糊、主体性模糊,易造成研究信效度难以认定、人机角色责任划分不清,产生学术伦理不端与研究者关键技能退化的风险。规范和引导大语言模型在学术研究中的应用,应增强研究者的主体性、重视研究的解释性与反思性、探索梯级人机协同研究策略与加强学术伦理建设。

关键词：生成式人工智能大语言模型学术研究人机协同

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柳树丛枝病病原分子鉴定

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植物病理学报 2024年第1期54卷 220-224页

作者：陈雅寒武崇高方健惠朱亚灵许宏刚程晓月欧阳经政甘肃农业大学植物保护学院兰州730070 甘肃省林业有害生物防治检疫站兰州7300703 兰州市园林科学研究所兰州730070

柳树(Willow)是杨柳科(Salicaceae)柳属(Salix)乔木植物,大多数品种具有耐旱耐盐碱的特性,对环境具有良好的适应能力[1]。柳树在甘肃省内广泛种植,是风景林、防护林和水土保持林的重要组成树种。柳树丛枝病是一种典型的植原体病害,当寄... 详细信息

柳树(Willow)是杨柳科(Salicaceae)柳属(Salix)乔木植物,大多数品种具有耐旱耐盐碱的特性,对环境具有良好的适应能力[1]。柳树在甘肃省内广泛种植,是风景林、防护林和水土保持林的重要组成树种。柳树丛枝病是一种典型的植原体病害,当寄主植株被病原物侵染时,顶芽生长受到抑制而侧芽提前萌发,导致受害枝条无法正常抽条或木质化,严重时甚至引起整株枯死[2],对林业的生态、经济和社会效益造成了极大损失。近年来,柳树丛枝病在甘肃省各市州发生严重,已经引起省内各界的普遍关注。

关键词：丛枝病水土保持林风景林抽条柳树分子鉴定防护林乔木植物

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SimHOEPI:A resampling simulator for generating single nucleotide polymorphism data with a high-order epistasis model

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Quantitative Biology 2024年第2期12卷 197-204页

作者： yahan Li Xinrui Cai Junliang Shang Yuanyuan Zhang Jin-Xing Liu School of Computer Science Qufu Normal UniversityRizhaoChina School of Information and Control Engineering Qingdao University of TechnologyQingdaoChina School of Health and Life Sciences University of Health and Rehabilitation SciencesQingdaoChina

Epistasis is a ubiquitous phenomenon in genetics,and is considered to be one of main factors in current efforts to unveil missing heritability of complex *** data is crucial for evaluating epistasis detection tools in genome-wide association studies(GWAS).Existing simulators normally suffer from two limitations:absence of support for high-order epistasis models containing multiple single nucleotide polymorphisms(SNPs),and inability to generate simulation SNP data *** this study,we proposed a simulator SimHOEPI,which is capable of calculating penetrance tables of high-order epistasis models depending on either prevalence or heritability,and uses a resampling strategy to generate simulation data *** of SimHOEPI are the preservation of realistic minor allele frequencies in sampling data,the accurate calculation and embedding of high-order epistasis models,and acceptable simulation time.A series of experiments were carried out to verify these properties from different *** results show that SimHOEPI can generate simulation SNP data independently with high-order epistasis models,implying that it might be an alternative simulator for GWAS.

关键词： high-order epistasis model penetrance table resampling strategy simulation single nucleotide polymorphisms

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Resorption efficiency of leaf nutrients in woody plants on Mt. Dongling of Beijing, North China

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Journal of Plant Ecology 2015年第5期8卷 530-538页

作者： Jianhua Zhang Zhiyao Tang Yongkai Luo Xiulian Chi yahan chen Jingyun Fang Haihua Shen State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China University of Chinese Academy of Sciences No.19A Yuquan RoadShijingshan DistrictBeijing 100049China Department of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface ProcessesPeking UniversityNo.5 Yiheyuan RoadHaidian DistrictBeijing 100871China

Aims To explore resorption efficiency of nitrogen(NrE)and phosphorus(PrE)of woody plants in relation to soil nutrient availability,climate and evolutionary history,in North *** We measured concentrations of nitrogen([N])and phosphorus([P])in both full expanded mature green and senescent leaves of the same individuals for 88 woody species from 10 sites of ***,beijing,*** built a phylogenetic tree for all these species and compared NrE and PrE among life forms(trees,shrubs and woody lianas)and between functional groups(N-fixers and non-N-fixers).We then explored patterns of NrE and PrE along gradients of mean annual temperature(MAT),soil inorganic N and available P,and phylogeny using a general linear *** Findingsmass-based NrE(NrEm)and PrE(PrEm)averaged 57.4 and 61.4%,respectively,with no significant difference among life forms or functional *** NrEm nor PrEm exhibited significant phylogenetic signals,indicating that NrEm and PrEm were not phylogenetically *** was not related to[N]in green leaves;PrEm was positively correlated with[P]in green leaves;however,this relationship disappeared for different *** decreased with[N]in senescent leaves,PrEm decreased with[P]in senescent leaves,for all species combined and for trees and *** decreased with soil inorganic N for all species and for shrubs;PrEm did not exhibit a significant trend with soil available P for all species or for different plant *** NrEm nor PrEm was significantly related to MAT for overall species and for species of different groups.

关键词： nitrogen concentration phosphorus concentration senesced leaves nitrogen resorption efficiency phosphorus resorption efficiency soil nutrient climate

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Highly selective growth of(6,5)single-walled carbon nanotubes from sigma phase alloy catalyst

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Nano Research 2024年第3期17卷 1999-2003页

作者： Liantao Xin chen Ma Qianru Wu Shaokang Liu Linhai Li Xiuyun Zhang Liu Qian Maoshuai He Dong Li Fangqian Han Shulan Hao Lihu Feng yahan Li Huaping Liu Lili Zhang Chang Liu Jin Zhang College of Chemistry and Molecular Engineering Qingdao University of Science and TechnologyQingdao 266042China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Physics Science and Technology Yangzhou UniversityYangzhou 225002China Center for Nanochemistry Beijing Science and Engineering Center for NanocarbonsBeijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

The chirality structure of a single-walled carbon nanotube(SWNT)strongly depends on the composition of catalyst used in the chemical vapor deposition *** this study,we develop a porous magnesia supported manganese-rhenium(MnRe/MgO)catalyst for chirality-selective synthesis of *** characterizations reveal that(6,5)tubes with a selectivity higher than 70%are grown from the Re-rich MnRe/MgO *** comparing the SWNT growth results with those of monometallic Mn or Re,the formation of sigma phase,an intermetallic compound occurring in transition-metal alloy systems,is revealed to be crucial for the dominant synthesis of(6,5)*** work not only extends the application of sigma phase alloy for catalytic synthesis of SWNTs,but also sheds lights on the growth of SWNTs with a high chirality selectivity.

关键词： single-walled carbon nanotubes sigma phase manganese-rhenium catalyst selective growth transition-metal alloy

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中西语境中教育治理的理论、政策与实践差异

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比较教育研究 2023年第12期45卷 3-12,21页

作者：苏君阳陈亚涵孙芳北京师范大学教育管理学院北京100875 哈尔滨师范大学教育科学学院黑龙江哈尔滨150025

教育治理体系与治理能力现代化的推进对于建设教育强国具有重要意义。西方教育治理,在理论上以新公共管理理论为主导框架,强调价值共识、多元主体参与;在政策上偏向管理主义;在实践上采取分散化治理模式,强调自治、竞争、参与、评价和... 详细信息

教育治理体系与治理能力现代化的推进对于建设教育强国具有重要意义。西方教育治理,在理论上以新公共管理理论为主导框架,强调价值共识、多元主体参与;在政策上偏向管理主义;在实践上采取分散化治理模式,强调自治、竞争、参与、评价和问责。中国教育治理,在理论上以中国式科层制理论为主导框架,强调整体利益、协同合作;在政策上偏向共同体主义;在实践上强调法治、公平、协调与认同。制度、文化和情境是导致中西语境中教育治理理论、政策与实践差异形成的主要影响因素。教育治理话语的建构不仅在于解释教育世界,而且也在于改造教育世界,从而服务于一个国家、民族、社会的建设与发展。因此,中西教育治理话语对实践均具有一定的解释力与能动性,也都存在着一定的局限。

关键词：中西语境教育治理治理话语话语差异话语张力

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The Reversible Methylation of m6A is Involved in Plant Virus Infection

The Reversible Methylation of m6A is Involved in Plant Virus...

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中国植物病理学会2023年学术年会

作者： YUE Jianying WEI Yao SUN Zhenqi chen yahan WANG Haijuan GUO Yuqing Fabio Pasin ZHAO Mingmin College of Plant Protection Gansu Agricultural University

N6-methyladenosine(m6 A) is the most prevalent modification in the mRNAs of many eukaryotie *** abundance and effects of m6 A are determined by dynamic interactions between its methyltransferases, demethylases, and binding *** of the alkylation B( AlkB)superfamily show RNA demethylase activity removing methyl adducts from *** erase(MTase) enzymes catalyze the addition of a methyl group to a variety of biological *** RNA immunoprecipitation sequencing of virus-infected samples showed that m6 A peaks are enriched in plant transcript 3 ’ UTR and in discrete internal and 3’ terminal regions of PPV and PVY *** addition, We find that m6 A levels in Nicotiana benthamiana( A’.benthamiana) are reduced by infection of plum pox virus and potato virus ***-regulation of A’, benthamiana AlkB homologues of the plant-specif ic ALKBH9 clade caused a significant decrease in PPV and PVY *** of NbMETTLl and NbMETTL2 caused a decrease of plum pox virus *** results suggest a general involvement of RNA methylation in potyvirus *** life cycles of plant RNA viruses are often coordinated with the mechanisms of their RNA *** appears that m6 A methylation plays a dual role during viral infection in *** the one hand, m6 A methylation acts as an antiviral immune response induced by virus infection, which inhibits viral replication or translation through the methylation of viral genome *** the other hand, plant viruses could disrupt the m6 A methylation through interacting with the key proteins of the m6 A pathway to avoid *** on this mechanism, we propose that new strategies for plant virus control could be designed with competitive antagonists of m6 A-associated proteins.

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Global leaf nitrogen and phosphorus stoichiometry and their scaling exponent

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National Science Review 2018年第5期5卷 728-739页

作者： Di Tian Zhengbing Yan Karl J.Niklas Wenxuan Han Jens Kattge Peter B.Reich Yongkai Luo yahan chen Zhiyao Tang Huifeng Hu Ian J.Wright Bernhard Schmid Jingyun Fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Max-Planck-Institute for Biogeochemistry State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences College of Life Sciences Capital Normal University Department of Plant Biology Cornell University Department of Forest Resources University of Minnesota Department of Biological Sciences Macquarie UniversitySydneyNSW 2109Australia10 Department of Evolutionary Biology and Environmental StudiesUniversity of Zurich Hawkesbury Institute for the Environment Western Sydney University Key Laboratory of Plant-Soil Interactions Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural University

Leaf nitrogen(N) and phosphorus(P) concentrations constrain photosynthetic and metabolic processes,growth and the productivity of plants. Their stoichiometry and scaling relationships regulate the allocation of N and P from subcellular to organism, and even ecosystem levels, and are crucial to the modelling of plant growth and nutrient cycles in terrestrial ecosystems. Prior work has revealed a general biogeographic pattern of leaf N and P stoichiometric relationships and shown that leaf N scales roughly as two-thirds the power of P. However, determining whether and how leaf N and P stoichiometries, especially their scaling exponents, change with functional groups and environmental conditions requires further verification. In this study, we compiled a global data set and documented the global leaf N and P concentrations and the N:P ratios by functional group, climate zone and continent. The global overall mean leaf N and P concentrations were 18.9 mg gand 1.2 mg g, respectively, with significantly higher concentrations in herbaceous than woody plants(21.72 mg gvs. 18.22 mg gfor N; and 1.64 mg gvs. 1.10 mg gfor P). Both leaf N and P showed higher concentrations at high latitudes than low latitudes. Among six continents, Europe had the highest N and P concentrations(20.79 and 1.54 mg g) and Oceania had the smallest values(10.01 and 0.46 mg g). These numerical values may be used as a basis for the comparison of other individual studies. Further, we found that the scaling exponent varied significantly across different functional groups,latitudinal zones, ecoregions and sites. The exponents of herbaceous and woody plants were 0.659 and0.705, respectively, with significant latitudinal patterns decreasing from tropical to temperate to boreal zones. At sites with a sample size ≥10, the values fluctuated from 0.366 to 1.928, with an average of *** factors including the intrinsic attributes of different life forms, P-related growth rates and relative nutrient availa

关键词： leaf nitrogen phosphorus stoichiometry scaling exponent functional group biogeography

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