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A nondestructive method for estimating the total green leaf area of individual rice plants using multi-angle color images

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Journal of Innovative Optical Health Sciences 2015年第2期8卷 7-18页

作者： Ni jiang Wanneng yang Lingfeng duan Guoxing Chen Wei Fang Lizhong Xiong Qian Liu Britton Chance Center for Biomedical Photonics Wuhan National Laboratory for Optoelectronics-Huazhong University of Science and Technology 1037 Luoyu Rd. Wuhan 430074P.R.China National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research Huazhong Agricultural University Wuhan 430070 P.R.China College of Engineering Huazhong Agricultural University Wuhan 430070 P.R.China MOA Key Laboratory of Crop Ecophysiology and Farming System in the Middle Reaches of the yangtze River College of Plant Science and Technology Huazhong Agricultural University Wuhan 430070 P.R.China

Total green leaf area(GLA)is an important trait for agronomic ***,existing methods for estimating the GLA of individual rice plants are destructive and labor-intensive.A nondestructive method for estimating the total GLA of individual rice plants based on multi-angle color images is *** projected areas of the plant in images,linear,quadratic,exponential and power regression models for estimating total GLA were *** demonstrated that the side-view projected area had a stronger relationship with the actual total leaf area than the top-projected *** power models fit better than other *** addition,the use of multiple side-view images was an efficient method for reducing the estimation *** inclusion of the top-view projected area as a seoond predictor provided only a slight improvement of the total leaf area est *** the projected areas from multi angle images were used,the estimated leaf area(ELA)using the power model and the actual leaf area had a high correlation cofficient(R2>0.98),and the mean absolute percentage error(MAPE)was about 6%.The method was capable of estimating the total leaf area in a nondestructive,accurate and eficient manner,and it may be used for monitoring rice plant growth.

关键词： Agri photonics image processing plant phenotyping regression model visible light imaging

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LOW RANK APPROXIMATION SOLUTION OF A CLASS OF GENERALIZED LYAPUNOV EQUATION

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Journal of Computational Mathematics 2016年第4期34卷 407-420页

作者： Xuefeng duan Zhuling jiang Anping Liao College of Mathematics and Computational Science Guilin University of Electronic Technology Guilin 541004 P.R. China Guangxi Colleges and Universities Key Laboratory of Data Analysis and Computation Guilin University of Electronic Teehnology Guilin 541004 P.R. China College of Mathematics and Econometrics Hunan University Changsha 410082 P.R. China

In this paper, we consider the low rank approximation solution of a generalized Lya- punov equation which arises in the bilinear model reduction. By using the variation prin- ciple, the low rank approximation solution problem is transformed into an unconstrained optimization problem, and then we use the nonlinear conjugate gradient method with ex- act line search to solve the equivalent unconstrained optimization problem. Finally, some numerical examples are presented to illustrate the effectiveness of the proposed methods.

关键词： Generalized Lyapunov equation Bilinear model reduction Low rank approxi-mation solution Numerical method.

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Effect of polybrominated diphenyl ether on development of cultured hippocampal neuron

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Science China Chemistry 2008年第1期51卷 62-68页

作者： LIAO Chunyang duan ShuMin jiang GuiBin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Institute of Neuroscience and Key Laboratory of Neurobiology Shanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China

Polybrominated diphenyl ether (PBDE) is a persistently environmental pollutant ubiquitously found in wildlife and humans. Although concern on PBDE’s toxic effects is steadily increasing, its action on the central nervous system (CNS) remains largely unknown. To address this issue, the present study ex- amined the development inhibition of PBDE in neurons. The primary cultured hippocampal neurons of rat were exposed to the commercial decabromodiphenyl ether (deca-BDE), and the neurite length, bi- furcation, and synapse formation and maturation were evaluated, based on the confocal microscope imaging. The results showed that the development inhibition in neurons occurred at 15 μmol/L, indi- cating that PBDE is a potent neurotoxicant and it might obviously inhibit the development of cultured neurons.

关键词： polybrominated diphenyl ether (PBDE) neuron neurite synapse development inhibition

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Weakly k-hyponormal and polynomially hyponormal commuting operator pairs

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Science China Mathematics 2015年第2期58卷 405-422页

作者： duan Yong jiang QI Ting Ting School of Mathematics and Statistics Northeast Normal University

We introduce the notion of weak k-hyponormality and polynomial hyponormality for commuting operator pairs on a Hilbert space and investigate their relationship with k-hyponormality and *** provide examples of 2-variable weighted shifts which are weakly 1-hyponormal but not *** relating the weak k-hyponormality and k-hyponormality of a commuting operator pair to positivity of restriction of some linear functionals to corresponding cones of functions,we prove that there is an operator pair that is polynomially hyponormal but not 2-hyponormal,generalizing Curto and Putinar’s result(1991,1993)to the two-variable case.

关键词： weakly k-hyponormal k-hyponormal polynomially hyponormal subnormal commuting operator pair

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An optimized two-step derivatization method for analyzing diethylene glycol ozonation products using gas chromatography and mass spectrometry

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Journal of Environmental Sciences 2017年第3期29卷 313-321页

作者： Ran Yu Lei duan Jingkun jiang Jiming Hao State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex Beijing 100084China

The ozonation of hydroxyl compounds （e.g., sugars and alcohols） gives a broad range of products such as alcohols, aldehydes, ketones, and carboxylic adds. This study developed and optimized a two-step derivatization procedure for analyzing polar products of aldehydes and carboxylic acids from the ozonation of diethylene glycol （DEG） in a non-aqueous environment using gas chromatography-mass spectrometry. Experiments based on Central Composite Design with response surface methodology were carried out to evaluate the effects of derivatization variables and their interactions on the analysis. The most desirable derivati- zation conditions were reported, i.e., oximation was performed at room temperature overnight with the o-（2,3,4,5,6-pentafluorobenzyl） hydroxyl amine to analyte molar ratio of 6, silylation reaction temperature of 70℃, reaction duration of 70 min, and N,O-bis（trimethylsilyl）- trifluoroacetamide volume of 12.5 μL. The applicability of this optimized procedure was verified by analyzing DEG ozonation products in an ultrafine condensation particle counter simulation system.

关键词： Gas chromatography-massspectrometryResponse surface methodologyCentral Composite DesignDiethylene glycol ozonation

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Space-time clutter model for airborne bistatic radar with non-Gaussian statistics

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Journal of Systems Engineering and Electronics 2009年第2期20卷 283-290页

作者： duan Rui Wang Xuegang jiang Chaoshu Chen Zhuming Dept.of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

To validate the potential space-time adaptive processing （STAP） algorithms for airborne bistatic radar clutter suppression under nonstationary and non-Gaussian clutter environments, a statistically non-Gaussian, space-time clutter model in varying bistatic geometrical scenarios is presented. The inclusive effects of the model contain the range dependency of bistatic clutter spectrum and clutter power variation in range-angle cells. To capture them, a new approach to coordinate system conversion is initiated into formulating bistatic geometrical model, and the bistatic non-Gaussian amplitude clutter representation method based on a compound model is introduced. The veracity of the geometrical model is validated by using the bistatic configuration parameters of multi-channel airborne radar measurement （MCARM） experiment. And simulation results manifest that the proposed model can accurately shape the space-time clutter spectrum tied up with specific airborne bistatic radar scenario and can characterize the heterogeneity of clutter amplitude distribution in practical clutter environments.

关键词： airborne bistatic radar clutter model geometry non-Gaussian

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Microstructure and mechanical behavior of a low-density Fe-12Mn- 9Al-1.2C steel prepared using centrifugal casting under near-rapid solidification

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Journal of Iron and Steel Research International 2018年第8期25卷 830-838页

作者： Wei He Bi-lei Wang yang yang Yun-hu Zhang Lian duan Zhi-ping Luo Chang-jiang Song Qi-jie Zhai State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and Engineering Shanghai UniversityShanghai 200444 China Department of Chemistry and Physics Fayetteville State University Fayetteville NC 28301 USA

It is vital for emission reduction and energy saving to lighten the weight of automobile. Low-density Fe-Mn-Al-C steels with high strength and excellent ductility have become a promising type of material in the automotive industry. Thus, a new approach was proposed by using centrifugal casting to produce the low-density Fe-12Mn-9Al-1.2C steel with high performance under near-rapid solidification in a near-net shape. The produced steel strips, with a thickness of 2.5 mm and a density of 6.89 g/cm3, were examined for their microstructures and mechanical properties. The results showed that mechanical properties of as-cast steel strip reached 1182 MPa in ultimate tensile strength and 28.1% in total elongation. Aging treatment at 400 or 600℃ for 3 h enhanced tensile strength of the steel strips, while aging at 800℃ dramatically decreased its elongation. Moreover, Young＇ s modulus of the steel strip improved with the increment of aging temperature. The relationship between the mechanical properties and the microstructures was discussed. The results demonstrated that advanced low-density steels with promising mechanical properties could be directly produced from liquid by this simple process.

关键词： Low-density steel Near-net shape Mechanical property Microstructure Near-rapid solidification

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Perturbation solutions of relativistic viscous hydrodynamics for longitudinally expanding fireballs

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Chinese Physics C 2020年第8期44卷 164-171页

作者： Ze-Fang jiang duan She C.B.yang Defu Hou Department of Physics and Electronic-Information Engineering Hubei Engineering UniversityXiaogan 432000China Institute of Particle Physics&Key Laboratory of Quark and Lepton Physics MOECentral China Normal UniversityWuhan 430079China Physics Department and Center for Exploration of Energy and Matter Indiana University2401 N Milo B.Sampson LaneBloomingtonIN 47408USA

The solutions of the relativistic viscous hydrodynamics for longitudinally expanding fireballs are investig-ated with the Navier-Stokes theory and Israel-Stewart *** energy and the Euler conservation equations for the viscous fluid are derived in Rindler coordinates,by assuming that the longitudinal expansion effect is *** the perturbation assumption,an analytical perturbation solution for the Navier-Stokes approximation and numerical solutions for the Israel-Stewart approximation are *** temperature evolution with both shear viscous ef-fect and longitudinal acceleration effect in the longitudinal expanding framework are *** specific temper-ature profile shows symmetric Gaussian shape in the Rindler ***,we compare the results from the Israel-Stewart approximation with the results from the Bjorken and the Navier-Stokes approximations,in the pres-ence of the longitudinal acceleration expansion *** found that the Israel-Stewart approximation gives a good description of the early stage evolutions than the Navier-Stokes theory.

关键词： heavy ion collision longitudinal expanding fireball viscous hydrodynamics Rindler coordinate

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The role of m6A modification in the biological functions and diseases

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Signal Transduction and Targeted Therapy 2021年第3期6卷 763-778页

作者： Xiulin jiang Baiyang Liu Zhi Nie Lincan duan Qiuxia Xiong Zhixian Jin Cuiping yang Yongbin Chen Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences&Yunnan Province Kunming Institute of Zoology650223 KunmingYunnanChina Kunming College of Life Science University of Chinese Academy of Sciences100049 BeijingChina Kunming Medical University 650500 KunmingChina Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences650223 KunmingYunnanChina

N6-methyladenosine(m6A)is the most prevalent,abundant and conserved internal cotranscriptional modification in eukaryotic RNAs,especially within higher eukaryotic cells.m6A modification is modified by the m6A methyltransferases,or writers,such as METTL3/14/16,RBM15/15B,ZC3H3,VIRMA,CBLL1,WTAP,and KIAA1429,and,removed by the demethylases,or erasers,including FTO and *** is recognized by m6A-binding proteins YTHDF1/2/3,YTHDC1/2 IGF2BP1/2/3 and HNRNPA2B1,also known as"readers".Recent studies have shown that m6A RNA modification plays essential role in both physiological and pathological conditions,especially in the initiation and progression of different types of human *** this review,we discuss how m6A RNA methylation influences both the physiological and pathological progressions of hematopoietic,central nervous and reproductive *** will mainly focus on recent progress in identifying the biological functions and the underlying molecular mechanisms of m6A RNA methylation,its regulators and downstream target genes,during cancer progression in above *** propose that m6A RNA methylation process offer potential targets for cancer therapy in the future.

关键词： m6A diseases removed

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A new benzylisoquinoline alkaloid from stems of Nelumbo nucifera

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Chinese Chemical Letters 2008年第3期19卷 308-310页

作者： Xu Hong duan Jian Qin jiang Department of Natural Medicine Chemistry China Pharmaceutical University Nanjing 210038 China

A new benzylisoquinoline alkaloid, named nelumstemine （1）, 1-（4＇-hydroxybenzoyl）-6,7-dimethoxy-3,4-dihydroisoquinoline, was isolated from the stems of Nelumbo nucifera Geartn. Its structure was established on the... 详细信息

关键词： Nelumbo nucifera Geartn Nelumstemine Dihydroisoquinoline Benzylisoquinoline alkaloids

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