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Forest biomass is strongly shaped by forest height across boreal to tropical forests in China

Journal of Plant Ecology 2015年第6期8卷 559-567页

作者： xian wu xiangping Wang Yulian wu Xinli Xia Jingyun Fang The Key Laboratory of Silviculture and Conservation of the Ministry of Education and the National Engineering Laboratory for Forest Genetics and Tree BreedingBeijing Forestry University35 East Qinghua RoadHaidianBeijing 100083China Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University5 Yiheyuan RoadHaidianBeijing 100871China

Forest height is a major factor shaping geographic biomass patterns,and there is a growing dependence on forest height derived from satellite light detecting and ranging(LiDAR)to monitor large-scale biomass ***,how the relationship between forest biomass and height is modulated by climate and biotic factors has seldom been quantified at broad scales and across various forest biomes,which may be crucial for improving broad-scale biomass estimations based on satellite *** We used 1263 plots,from boreal to tropical forest biomes across China,to examine the effects of climatic(energy and water avail-ability)and biotic factors(forest biome,leaf form and leaf phenol-ogy)on biomass-height relationship,and to develop the models to estimate biomass from forest height in *** Findings(i)Forest height alone explained 62%of variation in forest biomass across China and was far more powerful than climate and other biotic factors.(ii)However,the relationship between biomass and forest height were significantly affected by climate,forest biome,leaf phenology(evergreen ***)and leaf form(needleleaf ***).among which,the effect of climate was stronger than other *** intercept of biomass-height relationship was more affected by precipitation while the slope more affected by energy availability.(iii)When the effects of climate and biotic factors were considered in the models,geographic biomass patterns could be well predicted from forest height with an r2 between 0.63 and 0.78(for each forest biome and for all biomes together).For most biomes,forest biomass could be well predicted with simple models includ-ing only forest height and climate.(iv)We provided the first broad-scale models to estimate biomass from forest height across China,which can be utilized by future LiDAR studies.(v)our results suggest that the effect of climate and biotic factors should be carefully considered in models estimating broad-scale forest biomass pa

关键词： biomass climate forest biome forest height leaf phenology needleleaf vs.broadleaf forest

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On the Category of Koszul Modules of Complexity One of an Exterior Algebra

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Acta Mathematica Sinica,English Series 2006年第3期22卷 849-854页

作者： Jin Yun GUO Bing Jun LI Qiu xian wu Department of Mathematics Hunan Normal University

In this paper, we prove that there is a natural equivalence between the category F1（x） of Koszul modules of complexity 1 with filtration of given cyclic modules as the factor modules of an exterior algebra A = ∧V of an m-dimensional vector space, and the category of the finite-dimensional locally nilpotent modules of the polynomial algebra of m - 1 variables.

关键词： exterior algebra Koszul module complexity

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Ceric(Ⅳ)-mediated Oxidative Addition of 1,3-Dicarbonyl Compounds to MCPs:A Facile Access to Dihydrofuran Derivatives Incorporating Cyclopropyl Groups

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Chinese Chemical Letters 2006年第5期17卷 569-570页

作者： Wan Li CHEN Lu Ling wu xian HUANG Department of Chemistry Zhejiang University （Xixi Campus） Hangzhou 310028

Alkylidenecyclopropanes undergo ceric（Ⅳ） ammonium nitrate （CAN）-mediated addition reaction with 1,3-dicarbonyl compounds leading to dihydrofuran derivatives incorporating cyclopropyl groups in moderate yields.

关键词： Alkylidenecyclopropane ceric(Ⅳ) ammonium nitrate (CAN) dihydrofuran derivatives.

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Effect of Silicon Content on Thermodynamics of Austenite Decomposition in C-Si-Mn TRIP Steels

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Journal of Iron and Steel Research International 2006年第3期13卷 57-60,73页

作者： ZHU Li-juan wu Di ZHAO xian-ming State Key Lab of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Some numerical models such as central atoms model （CAM） and superelement model were used to simulate the thermodynamics of austenite decomposition in the Fe-C-Mn-Si TRIP （transformation induced plasticity） steels. Thermodynamic calculations were carried out under a para-equilibrium （PE） condition. The results show that certain silicon content can accelerate the polygonal ferritic transformation and increase the volume fraction and stability of retained austenite by retarding the precipitation of carbides during the bainitic transformation.

关键词： central atoms model superelement model para-equilibrium austenite decomposition TRIP steel

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Selfinjective Koszul Algebras of Finite Complexity

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Acta Mathematica Sinica,English Series 2009年第12期25卷 2179-2198页

作者： Jin Yun GUO Ai Hua LI Qiu xian wu Department of Mathematics Xiangtan University Xiangtan 411105 P. R. China Department of Mathematics Hu'nan Normal University Changsha 410081 P. R. China

In this paper, we study selfinjective Koszul algebras of finite complexity. We prove that the complexity is a nonnegative integer when it is finite; and that the category Yt of modules with complexity less or equal to t, is resolving and coresolving. We show that for each 0 ≤ 1 ≤ m there exist a family of modules of complexity 1 parameterized by G（l, m）, the Grassmannian of l-dimensional subspaces of an m-dimensional vector space V, for the exterior algebra of V. Using complexity, we also give a new approach to the representation theory of a tame symmetric algebra with vanishing radical cube over an algebraically closed field of characteristic 0, via skew group algebra of a finite subgroup of SL（2, C） over the exterior algebra of a 2-dimensional vector space.

关键词： selfinjective Koszul algebra complexity skew group algebra tame symmetric algebra

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On the Koszul Modules of Exterior Algebras

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Acta Mathematica Sinica,English Series 2007年第11期23卷 1967-1984页

作者： Jin Yun GUO Quan Hong WAN Qiu xian wu Department of Mathematics Xiangtan University Xiangtan 411105 P. R. China Department of Mathematics Hu'nan Normal University Changsha 410081 P. R. China

We prove that the Koszul modules over an exterior algebra can be filtered by the cyclic Koszul modules. We also introduce the cyclic dimension vector as invariants for studying the Koszul modules over an exterior alge... 详细信息

关键词： exterior algebra Koszul module cyclic dimension vector

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日常活动能力在老年人关节炎和抑郁症状间的中介效应研究

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现代预防医学 2024年第1期51卷 123-126+155页

作者：张思思王伟利李林吴君娴沈勤浙江中医药大学护理学院

目的探讨日常生活能力在老年人关节炎和抑郁症状间的中介效应，为预防和干预老年人抑郁症的发生发展提供参考依据。方法基于2018年CHARLS数据，采用逐步回归分析和Bootstrap中介检验分析日常活动能力在老年人关节炎与抑郁症状间的中... 详细信息

目的探讨日常生活能力在老年人关节炎和抑郁症状间的中介效应，为预防和干预老年人抑郁症的发生发展提供参考依据。方法基于2018年CHARLS数据，采用逐步回归分析和Bootstrap中介检验分析日常活动能力在老年人关节炎与抑郁症状间的中介效应。结果关节炎患病率为8.12%，抑郁症状检出率44.60%。关节炎与日常活动能力呈正相关(r=0.025,P<0.05)，关节炎与抑郁症状呈正相关(r=0.036,P<0.01)，日常活动能力与抑郁症状呈正相关(r=0.348,P<0.001)。日常活动能力在关节炎和抑郁症状之间起部分中介作用，日常生活能力对抑郁症状的中介效应值为0.009，中介效应为总效应的25.71%。讨论关节炎可通过日常活动能力对老年人抑郁症状产生一定影响，应采取综合性干预措施改善老年人关节健康，减低关节炎患病情况，提高老年人日常活动能力，进而预防老年人抑郁的发生。

关键词：老年人抑郁症状关节炎日常活动能力中介作用

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An experimental study on size distribution and zeta potential of bulk cavitation nanobubbles

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International Journal of Minerals,Metallurgy and Materials 2020年第2期27卷 152-161页

作者： Xu-yu Zhang Qian-shuai Wang Zhong-xian wu Dong-ping Tao School of Mining Engineering University of Science and Technology LiaoningAnshan 114051China School of Resources and Environmental Engineering Shandong University of TechnologyZibo 255049China

Nanobubble flotation technology is an important research topic in the field of fine mineral particle *** basic characteristics of nanobubbles,including their size,concentration,surface zeta potential,and stability have a significant impact on the nanobubble flotation *** this paper,bulk nanobubbles generated based on the principle of hydrodynamic cavitation were investigated to determine the effects of different parameters(e.g.,surfactant(frother)dosage,air flow,air pressure,liquid flow rate,and solution pH value)on their size distribution and zeta potential,as measured using a nanoparticle *** results demonstrated that the nanobubble size decreased with increasing pH value,surfactant concentration,and cavitation-tube liquid flow rate but increased with increasing air pressure and increasing air flow *** magnitude of the negative surface charge of the nanobubbles was positively correlated with the pH value,and a certain relationship was observed between the zeta potential of the nanobubbles and their *** structural parameters of the cavitation tube also strongly affected the characteristics of the *** results of this study offer certain guidance for optimizing the nanobubble flotation technology.

关键词： nanobubble hydrodynamic cavitation zeta potential size distribution

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瓜实蝇雄性决定因子基因MoY功能及其上游调控序列活性分析

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昆虫学报 2024年第3期67卷 339-345页

作者：符竣凯温健曹凤勤颜日辉林先武海南大学热带农林学院(农业农村学院、乡村振兴学院) 儋州570228

【目的】本研究旨在鉴定瓜实蝇Zeugodacus cucurbitae雄性决定因子基因MoY上游调控序列,并探索该序列在胚胎早期驱动MoY表达对瓜实蝇性别决定的影响,为后续的瓜实蝇转基因品系的构建提供参考依据以及可用元件。【方法】使用基因组步移... 详细信息

【目的】本研究旨在鉴定瓜实蝇Zeugodacus cucurbitae雄性决定因子基因MoY上游调控序列,并探索该序列在胚胎早期驱动MoY表达对瓜实蝇性别决定的影响,为后续的瓜实蝇转基因品系的构建提供参考依据以及可用元件。【方法】使用基因组步移法扩增瓜实蝇Y染色体连锁的MoY上游序列并测序,将获得的上游序列连接MoY的CDS区构建其驱动MoY表达的质粒;将MoY表达质粒注射进瓜实蝇新鲜的胚胎中,待胚胎孵化后观察成虫的表型以及性比并提取基因组DNA,通过使用基因组DNA扩增MoY以判断获得的MoY上游调控序列是否具有驱动MoY表达的功能,同时分析MoY在胚胎中的表达对性别决定的影响。【结果】克隆并获得瓜实蝇MoY上游1660 bp序列,构建该序列驱动MoY表达的质粒p1660。由注射胚胎发育而来的瓜实蝇雄成虫18头和雌成虫13头及另外发现3头成虫的生殖器发育异常且MoY的扩增结果为阴性,确认为间性个体。【结论】本研究通过对MoY进行基因组步移扩增发现所获得的瓜实蝇MoY上游调控序列具有驱动MoY表达的活性,当MoY于瓜实蝇胚胎早期表达可使原本发育为雌性的个体出现性别逆转的现象。

关键词：瓜实蝇 MoY 上游调控序列性别逆转间性个体

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Amphiphilic Graft Copolymers of Hydroxypropyl Cellulose Backbone with Nonpolar Polyisobutylene Branches

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Chinese Journal of Polymer Science 2021年第8期39卷 1029-1039,I0007页

作者： Jin-Rui Deng Cong-Lei Zhao Zhi-Tao Wei Yi-xian wu State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing Laboratory of Biomedical MaterialsBeijing University of Chemical TechnologyBeijing 100029China

The novel amphiphilic graft copolymers with hydrophilic hard polar hydroxypropyl cellulose(HPC)backbone and hydrophobic soft nonpolar polyisobutylene(PIB)branches have been successfully synthesized through nucleophilic substitution reaction of living PIB chains carrying oxonium ions with the-OH groups along HPC *** PIB branch length in the graft copolymers could be designed by living cationic polymerization and the grafting density could be adjusted by PIB+/-OH molar *** living PIB chains carrying oxonium ion were prepared by transformation of allyl bromide end groups in the presence of AgCI0_(4) and silver nanoparticles(3.2±0.3 nm,0.7 wt%-1.8 wt%)generated in situ from *** phase-separation morphology was formed in the graft copolymers due to their incompatibility between backbone and *** hydrophilicity on the surface of graft copolymer films could be turned to hydrophobicity by increasing grafting density or/and length of PIB *** soft PIB segments in graft copolymers provided an unique surface wa self-assembly for ant卜protein adsorption against bovine serum albumin.A small amount of Ag nanoparticles in the copolymers contributed to good antibacterial activities against Staphylococcus aureus or Escherichia coli.

关键词： Hydroxypropyl cellulose Polyisobutylene Graft copolymer Cationic polymerization

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