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Effects of Vegetation Cover and Rainfall Intensity on Sediment-Bound Nutrient Loss,Size Composition and Volume Fractal Dimension of Sediment Particles

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Pedosphere 2011年第5期21卷 676-684页

作者： ZHANG Guan-Hua LIU guo-Bin wang guo-liang wang Yu-Xia College of Resource and Environment Northwest A&F University Yangling 712100 (China) Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 (China)

Vegetation and rainfall are two important factors affecting soil erosion and thus resulting in nutrient loss in the Chinese Loess Plateau.A field experiment was conducted to investigate the effects of rainfall intensities(60,100 and 140 mm h-1) and vegetation(Caragana korshinskii) coverages(0%,30% and 80%) on soil loss,nutrient loss,and the composition and volume fractal dimension of eroded sediment particles under simulated rainfall *** results showed that vegetation cover,rainfall intensity and their interaction all had significant effects on sediment transport and the sedimentbound nutrient *** rainfall intensity and lower coverage led to higher sediment and nutrient *** linear relationships were observed between soil loss and nutrient *** treatments showed more significant effects on the enrichment ratio(ER) of nitrogen(ERN) than organic matter(EROM) and phosphorus(ERP).Compared with the original surface soil,the eroded sediment contained more fine *** the same coverage,the clay content significantly decreased with increasing rainfall *** ER of sediment-bound nutrients was positively correlated with that of clay,suggesting that the clay fraction was preferentially eroded and soil nutrients were mainly adsorbed onto or contained within this *** were increments in the fractal dimension of the sediment particles compared to that of the original surface ***,the fractal dimension was positively correlated with clay,silt,and sediment-bound OM,N,and P contents,whereas it was negatively correlated with sand *** study demonstrated that fractal dimension analysis can be used to characterize differences in particle-size distribution and nutrient loss associated with soil erosion.

关键词： fractal features Loess Plateau particle-size distribution runoff nutrients simulated rainfall

Real Heat Flux Analysis of Continuously Casting Round Billet

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Journal of Iron and Steel Research International 2008年第1期15卷 25-29页

作者： ZHAN Hui-ying wang Xu-dong guo liang-liang YAO Man School of Material Science and Engineering Dalian University of Technology Dalian 116024 Liaoning China

The distributions of heat flux along the height and the circumferential direction of round billet mould were measured *** influence of casting speed,carbon content,powder,and pouring temperature on the average longitudinal and circumferential heat flux in the ＂high heat flux region＂ was *** experimental and analytical results provide a basis for an intelligent mould with online detection of defects,adjustment of operational parameters,optimization of the monitoring system,and even prediction of abnormal heat transfer.

关键词： continuous casting mould heat flux round billet

Bioinformatic analysis and functional characterization of the cfem proteins in maize anthracnose fungus Colletotrichum graminicola

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Journal of Integrative Agriculture 2020年第2期19卷 541-550页

作者： GONG An-dong JING Zhong-ying ZHANG Kai TAN Qing-qun wang guo-liang LIU Wen-de State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China College of Life Science Xinyang Normal UniversityXinyang 464000P.R.China Department of Plant Pathology The Ohio State UniversityColumbusOhio 43210USA

Fungal secreted proteins that contain the Common in Fungal Extracellular Membrane(CFEM)domain are important for *** hemibiotrophic fungus Colletotrichum graminicola causes the serious anthracnose disease of *** this study,we identified 24 CgCFEM proteins in the genome of *** analysis revealed that these 24 proteins(CgCFEM1–24)can be divided into 2 clades based on the presence of the trans-membrane *** alignment analysis indicated that the amino acids of the CFEM domain are highly conserved and contain 8 spaced cysteines,with the exception that CgCFEM1 and CgCFEM24 lack 1 and 2 cysteines,*** CgCFEM proteins with a signal peptide and without the trans-membrane domain were considered as candidate effectors and,thus were selected for structural prediction and functional *** CFEM domain in the candidate effectors can form a helical-basket structure homologous to the Csa2 protein in Candida albicans,which is responsible for haem acquisition and *** localization analysis revealed that these effectors accumulate in the cell membrane,nucleus,and cytosolic ***,5 effectors,CgCFEM6,7,8,9 and 15,can suppress the BAX-induced programmed cell death in Nicotiana benthamiana with or without the signal *** results demonstrate that these 10 CgCFEM candidate effectors with different structures and subcellular localizations in host cells may play important roles during the pathogenic processes on maize plants.

关键词： CFEM domain candidate effector anthracnose disease maize Colletotrichum graminicola

QTL Detection for Rice Grain Shape Using Chromosome Single Segment Substitution Lines

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Rice science 2011年第4期18卷 273-278页

作者： Sheng-qiang LI guo-kun CUI Cheng-ran GUAN Jun wang guo-hua liang Jiangsu Key Laboratory of Crop Genetics and Physiology / Key Laboratory of the Ministry of Education for Plant Functional Genomics Yangzhou University Yangzhou 225009 China

Rice grain shape is one of the important factors affecting grain quality and yield,but it is liable to be influenced by genetic backgrounds and *** chromosome single segment substitution lines(SSSLs) in rice have been considered as ideal populations to identify the quantitative trait loci(QTLs).In this study,22 QTLs affecting rice grain shape were detected to be distributed on eight chromosomes except chromosomes 6,9,11 and 12 by using *** them,seven QTLs conditioned grain length,six conditioned grain width,five affected grain length-width ratio and four controlled grain thickness.

关键词： rice single segment substitution line grain shape quantitative trait locus

特高压支架-设备体系动力响应简化分析及参数研究

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工程力学 2015年第3期32卷 82-89页

作者：李黎汪国良胡亮李果华中科技大学土木工程与力学学院湖北武汉430074 华中科技大学控制结构湖北省重点实验室湖北武汉430074

提出特高压支架-设备耦合体系动力分析的简化模型并据此针对体系动力特性及地震响应开展研究。首先分析支架-设备耦合体系的结构特点,提出考虑分布参数的体系2E-4D简化模型,推导了基于该模型的体系自振频率和地震响应计算公式。然后,针... 详细信息

提出特高压支架-设备耦合体系动力分析的简化模型并据此针对体系动力特性及地震响应开展研究。首先分析支架-设备耦合体系的结构特点,提出考虑分布参数的体系2E-4D简化模型,推导了基于该模型的体系自振频率和地震响应计算公式。然后,针对2种典型电气设备,对比分析了6组不同支架-设备耦合体系数值仿真和简化模型分析所得计算结果,验证了简化模型的准确性。最后,利用简化模型考察了不同特征参数(如刚度比、高度比等)对体系动力特性及响应的影响,并得到支架对设备加速度动力放大系数的取值规律。研究结果对《电力设施抗震设计规范》中有关支架对电气设备动力响应影响相关规定的修订具有参考价值。

关键词：特高压支架-设备体系简化模型动力放大系数有限元分析参数分析

Dietary Daidzein Enhances Antiapoptotic Effect of 17β-Estradiol (E_2) on Breast Cancer MCF-7 Cells

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Chinese Journal of Cancer Research 2010年第1期22卷 10-16页

作者： Xiao-fei Wu Yi-jing wang guo-liang Xia Mei-jia Zhang State Key Laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100193 China

Objective： To investigate whether dietary daidzein interact with endogenous 17β-Estradiol （E2） to give rise to additive or inhibitory effects on proliferation and apoptosis in breast cancer cells. Methods： Cell cycle distribution and apoptosis induction were analyzed by using flow cytometry when breast cancer cell lines MCF-7 were cotreated with daidzein （1, 5 μmol/L） and E2 （0.1-10 nmol/L） for 5 days. Whether daidzein could alter E2-modulated mRNA expression of estrogen receptor alpha （ERα）, estrogen receptor beta （ERI3） and ERβ-estrogen response element （ERE） dependent transcription was investigated by RT-PCR and luciferase induction assays. The effects of daidzein on E2-modulated expression of proapoptotic p53, bax and antiapoptotic bcl-2 at both mRNA and protein levels were also investigated by RT-PCR and Western blot. Results： Daidzein enhanced the antiapoptotic effect in an Ea dose-dependent manner, but had no effect on E2-induced proliferation. Daidzein antagonized E2-induced ERβ mRNA expression and ERβ-ERE dependent transcription. In addition, daidzein only antagonized E2-upregulated expression of p53 and bax, but had no effect on E2-upregulated expression of bcl-2. Conclusion： Daidzein enhances the antiapoptotic effect of E2 on breast cancer cells by inhibiting E2-mediated p53-bax proapoptotic pathway. These results suggest that dietary daidzein may enhance deleterious effect of endogenous E2 in hormone-dependent breast cancer.

关键词： Daidzein E2 Breast cancer MCF-7 cells Antiapoptotic effect Estrogen receptor (ER)

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高速铁路特殊咽喉区接触网布置研究

铁道工程学报 2017年第10期34卷 73-77页

作者：王国梁中国铁路设计集团有限公司天津300251

研究目的:在某高速铁路站场设计中,由于地形以及投资等限制,咽喉区的道岔组合采取特殊形式,在42号道岔与18号道岔之间仅有117 m的距离,需要在不改动既有站场布置的前提下,接触网专业根据受电弓型号及其动态包络线、定位柱处接触线拉出... 详细信息

研究目的:在某高速铁路站场设计中,由于地形以及投资等限制,咽喉区的道岔组合采取特殊形式,在42号道岔与18号道岔之间仅有117 m的距离,需要在不改动既有站场布置的前提下,接触网专业根据受电弓型号及其动态包络线、定位柱处接触线拉出值、定位柱支持装置的几何尺寸、道岔型号等资料对咽喉区的道岔接触网进行精确的布置研究,通过明确的几何关系研究进行接触网线岔布置,从而保证受电弓高速、安全、平滑通过线岔区,避免土建工程的改造。研究结论:(1)未改变既有站场布置,采用带辅助导向锚段的三支无交叉接触网布置方式与简单无交叉接触网布置方式结合,利用正线接触悬挂和侧线接触悬挂之间的辅助导线锚段悬挂转换,合理布置几组接触悬挂的空间位置;(2)该研究成果既做到结构简单、便于检调、维护工作量少,又能够满足接触网系统硬点、弹性等指标,从而保证受电弓从正线高速通过、从正线进入侧线、从侧线进入正线等过程中的行车安全和供电质量;(3)该研究成果适应于高速铁路特殊复杂咽喉区接触网的布置,可结合站场方案灵活组合,对高速铁路引入既有线土建受限条件下的接触网布置具有参考价值。

关键词：高速铁路接触网咽喉区布置

Markov系统矩阵未知情况下的控制器设计

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控制与决策 2016年第7期31卷 1265-1271页

作者：王国良秦奋辽宁石油化工大学信息与控制工程学院辽宁抚顺113001

针对Markov系统矩阵参数未知的实际情况,提出一种基于状态反馈控制与自适应控制相结合的控制方法.基于线性矩阵不等式技术给出相应控制器参数的求解条件.与现有大多数自适应控制方法相比,所提方法不仅使估计误差几乎处处有界,而且原系... 详细信息

针对Markov系统矩阵参数未知的实际情况,提出一种基于状态反馈控制与自适应控制相结合的控制方法.基于线性矩阵不等式技术给出相应控制器参数的求解条件.与现有大多数自适应控制方法相比,所提方法不仅使估计误差几乎处处有界,而且原系统的系统状态几乎处处渐近稳定,具有较好的收敛特性.在所得结果的基础上,进一步讨论了转移速率部分未知时的相关控制问题.数值算例验证了所提出的设计方法的有效性.

关键词： Markov跳变系统系统矩阵未知自适应控制转移速率部分未知几乎处处渐近稳定

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基于粒子滤波的多自由度运动目标跟踪

光学精密工程 2011年第4期19卷 864-869页

作者：王国良刘金国中国科学院长春光学精密机械与物理研究所吉林长春130033

为了在复杂背景下跟踪视频序列中的多自由度运动目标,基于粒子滤波理论提出了一种多自由度运动目标的稳健跟踪算法。首先,采用均值漂移算法目标模型与候选模型的相似度作为观测值的构造基础;然后,在核函数下颜色直方图的基础上,对目标... 详细信息

为了在复杂背景下跟踪视频序列中的多自由度运动目标,基于粒子滤波理论提出了一种多自由度运动目标的稳健跟踪算法。首先,采用均值漂移算法目标模型与候选模型的相似度作为观测值的构造基础;然后,在核函数下颜色直方图的基础上,对目标的中心位置和表征目标形状的协方差矩阵进行更新,从而自适应地调整核函数带宽的大小,修正跟踪窗口的尺寸,实现对多自由度运动目标的跟踪。在粒子滤波中,取粒子数N为100,目标参考区域中心在x,y轴上的坐标分量随机游动的方差为5,参考区域在x,y轴上的尺度及角度随机游动的方差为0.1;在不同场景和不同目标的跟踪实验中,提出的算法能够稳健、可靠地跟踪多自由度运动目标,对目标尺度和角度变化具有良好的适应性。

关键词：目标跟踪粒子滤波多自由度核带宽均值漂移