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Current Zoology 2018年第6期64卷 733-743页

作者： Ashley M.JOHNSON chia-hao chang Rebecca C.FULLER Department of Animal Biology School of Integrative BiologyUniversity of Illinois at Urbana-ChampaignChampaignIL 61820USA

The maintenance of genetic variation in the face of natural selection is a long-standing question in evolutionary *** the bluefin killifish Lucania goodei,male coloration is *** can produce either red or yellow coloration in their anal fins,and both color morphs are present in all *** 2 morphs are heritable and how they are maintained in nature is ***, we tested 2 mechanisms for the maintenance of the red/yellow color *** frequency-dependent mating success predicts that rare males have a mating advantage over common males. Spatial variation in fitness predicts that different color morphs have an advantage in different microhabitat *** a breeding experiment,we tested these hypotheses by creating populations with different ratios of red to yellow males (5 red:1 yellow;1 red:5 yellow)and determining male mating success on shallow and deep spawning *** found no evidence of negative frequency-dependent mating *** morphs tended to have higher mating success, and this was particularly so on shallow spawning ***,on deep substrates,red males enjoyed higher mating success than yellow males,particularly so when red males were rare. However,yellow males did not have an advantage at either depth nor when *** suggest that preference for red males is expressed in deeper water,possibly due to alterations in the lighting ***,male pigment levels were correlated with one another and predicted male mating ***,pigmentation plays an important role in male mating success.

关键词： carotenoid color polymorphism environmental heterogeneity melanin negative frequency dependence pterin

核磁共振显微术的DESIRE效应模拟(英文)

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波谱学杂志 2010年第3期27卷 396-408页

作者：张家豪王福年清华大学生医工程与环境科学系台湾新竹30013

要在合理时间內进行微米等级解析度的扫描时,核磁共振波谱的信噪比一直是一个很大的限制. DESIRE效应利用扩散现象来增强信号强度及解析度的概念被提出后,信噪比在一维的情况下大约可以增加一个数量级.在先期的研究中,模拟外加磁场的效... 详细信息

要在合理时间內进行微米等级解析度的扫描时,核磁共振波谱的信噪比一直是一个很大的限制. DESIRE效应利用扩散现象来增强信号强度及解析度的概念被提出后,信噪比在一维的情况下大约可以增加一个数量级.在先期的研究中,模拟外加磁场的效应通常是使用叠代数值计算,而扩散的效应则是利用有限微分法解Bloch-Torrey e-quation ,这样的模拟方法通常很耗时.该研究中,分别使用Shinnar-LeRoux演算法及基于旋积的扩散模拟方法来加速计算出外加磁场及扩散对于信号的影响,因此可以节省大量计算时间以进行复杂的计算.利用一维模拟结果预测在不同参数实验中解析度的改变和信号增加值,并找出最佳的参数值.而由模拟结果指出,Sinc3脉冲波形可以得到最佳的信号增加量及不错的解析度.

关键词：核磁共振显微术 DESIRE效应电脑模拟

浙江古田山亚热带常绿阔叶林开花物候：气候因素、系统发育关系和功能性状的影响

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生物多样性 2015年第5期23卷 601-609页

作者：胡小丽张杨家豪米湘成杜彦君常朝阳西北农林科技大学生命科学学院陕西杨凌712100 台湾东海大学生命科学系中国台湾台中40704 中国科学院植物研究所植被与环境变化国家重点实验室北京100093

植物的开花物候受气候因素、植物系统发育关系和功能性状的影响。然而当前植物开花物候研究中未见同时考虑这3个因素的报道。为了解它们相互之间的影响,本研究利用中国东部地区浙江省古田山国家级自然保护区亚热带常绿阔叶林24 ha大样地... 详细信息

植物的开花物候受气候因素、植物系统发育关系和功能性状的影响。然而当前植物开花物候研究中未见同时考虑这3个因素的报道。为了解它们相互之间的影响,本研究利用中国东部地区浙江省古田山国家级自然保护区亚热带常绿阔叶林24 ha大样地(GTS;118°03′50′′–118°11′12.2′′E,29°10′19′′–29°17′41′′N)设置的130个种子雨收集器5年的开花数据检验这3个因素对开花的影响。结果表明,古田山植物的开花高峰期集中在5月,群落开花格局明显受温度和降雨的影响。利用植物DNA条形码数据研究发现,植物间系统发育关系对古田山植物开花时间有显著影响,亲缘关系近的物种开花时间更相近。植物的平均开花时间受最大树高的影响,但不受传粉方式、花色、种子质量和扩散方式的影响。该研究结果说明气候因素、植物系统发育关系和功能性状都可能影响植物开花物候格局,同时考虑这3个因素能够帮助我们更好地理解开花物候格局。

关键词：气候功能性状古田山开花物候系统发育保守性

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu hao-Yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie Xu Ya-Qi Li Zhi-Zhen Ren Liang Wang Wei-chang hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

Deciphering fungal metabolon coupling tandem inverse-electrondemand Diels-Alder reaction and semipinacol rearrangement for the biosynthesis of spiro polycyclic alkaloids

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Science China Chemistry 2025年第1期68卷 288-296页

作者： Shuai Liu Wen-Qiang Xu Ying-Tong Di Man-Cheng Tang Ding-Kang Chen Ming-Ming Cao Yao-Wen chang Hong-Yu Tang Chun-Mao Yuan Jun-Bo Yang Zhi-Li Zuo Han Guo Zi-Fei Xu Ying Zeng Yun-Dong Wu Xiao-Jiang hao Key Laboratory of Phytochemistry and Natural Medicines (Chinese Academy of Sciences) Kunming Institute of Botany Chinese Academy of Sciences University of Chinese Academy of Sciences Lab of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen Bay Laboratory State Key Laboratory of Microbial Metabolism School of Life Sciences & Biotechnology Shanghai Jiao Tong University State Key Laboratory of Functions and Applications of Medicinal Plants Guizhou Medical University Molecular Biology Experimental Center Germplasm Bank of Wild Species in Southwest China Kunming Institute of Botany Chinese Academy of Sciences Yunnan Key Laboratory for Wild Plant Resources Kunming Institute of Botany Chinese Academy of Sciences Research Unit of Chemical Biology of Natural Anti-Virus Products Chinese Academy of Medical Sciences

In the intricate process of natural product biosynthesis, a metabolon can enhance metabolic flux by associating sequential enzymes. A fungal metabolon, comprising of flavin-dependent monooxygenase Spe F and P450 monooxygenase Spe G, is identified in the biosynthesis of spiro polycyclic alkaloids(+)-notoamide B and its diastereomer(+)-versicolamide B. Using notoamide E as a substance, Spe F/Spe G metabolon can control the stereoselectivity of its 2,3-epoxidation, followed by hydrogen atom ion at C-17 to generate reactive epoxide tau-m A with dienyl iminium unit. Subsequently,(+)-notoamide B and(+)-versicolamide B are produced via tandem nonenzymatic inverse-electron-demand Diels-Alder reaction and semipinacol rearrangement. This provides the first example of metabolon in the biosynthesis of spiro-prenylated indole alkaloids.

关键词： metabolon Diels-Alder reaction semipinacol rearrangement biosynthesis notoamides spiro polycyclic alkaloids

An Adaptive Bandwidth Allocation for Energy Efficient Wireless Communication Systems

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Journal of Electronic Science and Technology 2015年第1期13卷 27-32页

作者： Yung-Fa Huang Che-hao Li Chuan-Bi Lin chia-Chi chang Department of Information and Communication Engineering Chaoyang University of Technology

In this paper, an energy efficient bandwidth allocation scheme is proposed for wireless communication systems. An optimal bandwidth expansion（OBE） scheme is proposed to assign the available system bandwidth for users. When the system bandwidth does not reach the full load, the remaining bandwidth can be energy-efficiently assigned to the other users. Simulation results show that the energy efficiency of the proposed OBE scheme outperforms the traditional same bandwidth expansion（SBE） scheme. Thus, the proposed OBE can effectively assign the system bandwidth and improve energy efficiency.

关键词： Bandwidth resource allocation energy efficiency optimal bandwidth expansion same bandwidth expansion

LEGENDRE TRANSFORM-DUAL SOLUTION FOR INVESTMENT AND CONSUMPTION PROBLEM UNDER THE VASICEK MODEL

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Journal of Systems Science & Complexity 2014年第5期27卷 911-927页

作者： chang hao chang Kai Department of Mathematics Tianjin Polytechnic University School of Management Tianjin University School of Finance Zhejiang University of Finance & Economics

This paper studies an investment and consumption problem with stochastic interest rate,where interest rate is governed by the Vasicek *** financial market is composed of one riskfree asset and one risky asset,in which stock price dynamics is assumed to be generally correlated with interest rate *** aim is to maximize expected utility of consumption and terminal wealth in the finite *** transform is used to deal with this investment and consumption problem and the explicit solutions of the optimal investment and consumption strategies with power and logarithm preference are ***,the authors add a numerical example to analyze the effect of market parameters on the optimal investment and consumption strategy and provide some economic implications.

关键词： Dynamic programming investment and consumption Legendre transform the closedform solution the Vasicek model

A Note on the Rank of a Restricted Lie Algebra

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Algebra Colloquium 2018年第4期25卷 653-660页

作者： hao chang School of Mathematics and Statistics Central China Normal University Wuhan 430079China

In this short note,we study the rank of a restricted Lie algebra(g,[p]),and give some applications which concern the dimensions of non-trivial irreducible *** also compute the rank of the restricted contact algebra.

关键词： restricted Lie algebra rank contact algebra

Kinetics of bainite-to-austenite transformation during continuous reheating in low carbon microalloyed steel

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International Journal of Minerals,Metallurgy and Materials 2013年第5期20卷 427-432页

作者： Ming chang hao Yu School of Materials Science and Engineering University of Science and Technology Beijing

A dilatometer was used to study the kinetics of bainite-to-austenite transformation in low carbon microalloyed steel with the initial microstructure of bainite during the continuous reheating process. The bainite-to-austenite trans- formation was observed to take place in two steps at low heating rate. The first step is the dissolution of bainite, and the second one is the remaining bainite-to-austenite transformation controlled by a dissolution process. The calculation result of the kinetics of austenite formation shows that the two steps occur by diffusion at low heating rate. However, at high heating rate the bainite-to-austenite transformation occurs in a single step, and the process is mainly dominated by shear. The growth rate of austenite reaches the maximum at about 835℃ at different heating rates and the growth rate of austenite as a function of temperature increases with the increase in heating rate.

关键词： low carbon steel microalloying bainite austenite phase transformations reheating kinetics

Mode-localized accelerometer with ultrahigh sensitivity

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Science China(Information Sciences) 2022年第4期65卷 238-250页

作者： hao KANG Bing RUAN Yongcun hao Honglong chang Ministry of Education Key Laboratory of Micro and Nano Systems for Aerospace School of Mechanical EngineeringNorthwestern Polytechnical University

The mode localization phenomenon is an effective technique to enhance sensor sensitivity,and some low noise floor mode-localized sensors,including accelerometers,mass sensors,and electrometers,have been successfully *** further improve the performance of the mode-localized accelerometer,we report a microelectromechanical system mode-localized accelerometer based on 4-degree of freedom （DoF） weakly coupled resonators （WCRs） with a stress-relief structure eliminating the thermal stress generated during the silicon-on-glass fabrication *** results show that compared with the state-of-the-art 3-DoF mode-localized accelerometer (4.40 g-1),the amplitude ratio-based sensitivity of the proposed accelerometer(119.36 V·g-1) is improved by 2612%.Moreover,the noise floor is 0.64μg·Hz-1/2from 0.01 to 3 Hz under the closed-loop *** the authors’best knowledge,this is the lowest measured noise floor for mode-localized accelerometers.

关键词： mode localization weakly coupled resonators accelerometer degree-of-freedom microe-lectromechanical system