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The roles of microRNAs in regulating root formation and growth in plants

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Journal of Integrative Agriculture 2022年第4期21卷 901-916页

作者： YAN Xiao-xiao liu xiang-yang CUI Hong ZHAO Ming-qin College of Tobacco Science Henan Agricultural University/National Tobacco Cultivation and Physiology and Biochemistry Research Center/Key Laboratory for Tobacco Cultivation of Tobacco IndustryZhengzhou 450002P.R.China

MicroRNAs(miRNAs) are small(ca. 20-24 nucleotides) non-coding RNAs that have recently been recognized as key post-transcriptional modulators of gene expression;and they are involved in many biological processes in plants, such as root growth and development. The miRNAs regulate root elongation, lateral root(LR) formation and adventitious root(AR) development in response to hormone signaling, nutrient uptake and biotic/abiotic stress. This review provides multiple perspectives on the involvement of miRNAs in regulating root growth and development in plants. We also discuss several crucial mechanisms of miRNAs, their relationships with transcription factors and the target gene-mediated hormone signaling interactions in the regulation of root growth and development.

关键词： microRNAs adventitious root lateral root primary root

Site-Selective Magnetic Moment Collapse in Compressed Fe_(5)O_(6)

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Chinese Physics Letters 2021年第8期38卷 151-155页

作者： Qiao-Ying Qin Ai-Qin yang xiang-Ru Tao liu-xiang yang Hui-yang Gou Peng Zhang MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Center for High Pressure Science and Technology Advanced Research Beijing 100094China

Iron oxide is one of the most important components in the Earth’s *** recent discovery of the stable presence of Fe_(5)O_(6) in the Earth’s mantle environment has stimulated significant interests in understanding of this new category of iron *** report the electronic structure and magnetic properties of Fe_(5)O_(6) calculated by the density functional theory plus dynamic mean field theory(DFT+DMFT)*** calculations indicate that Fe_(5)O_(6) is a conductor at ambient pressure with dominant Fe-3 d density of states at the Fermi *** magnetic moments of iron atoms at three non-equivalent crystallographic sites in Fe_(5)O_(6) collapse at significantly different rates under *** site-selective collapse of magnetic moments originates from the shifting of energy levels and the consequent charge transfer among the Fe-3 d orbis when Fe_(5)O_(6) is being *** simulations suggest that there could be high conductivity and volume contraction in Fe_(5)O_(6) at high pressure,which may induce anomalous features in seismic velocity,energy exchange,and mass distribution in the deep interior of the Earth.

关键词： theory magnetic

Synthesis and Properties of a Novel Polyimide with Side Chain Containing Biphenyl Unit

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Chemical Research in Chinese Universities 2012年第2期28卷 334-339页

作者： WANG Xu CHANG Tong-xin ZHANG Peng CHEN Yi liu xiang-yang State Key Laboratory of Polymeric Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065P.R.China

A novel biphenyl side-chained diamine with alkyloxy spacer and alkyloxy tail,4＇-butoxy-4-（3,5-diaminobenzoyloxy）hexyloxybiphenyl（C6BBC4）,was synthesized and characterized by FTIR and 1 H NMR.A series of polyimide（PI） films with different side chain contents was synthesized from biphenyltetracarboxylicdianhydride（BPDA）,4,4＇-oxydianiline（ODA） and C6BBC4,and their thermal properties,optical transparency and liquid crystal alignment property,and so on,were investigated by thermogravimetric analysis（TGA）,differential scanning calorimetry（DSC）,crystal rotation method,polarizing microscopy and UV-Vis *** the content of side chained diamine increasing from 0 to 100%,the η inh of poly（amide acid）（PAA） decreased rapidly from 3.0 to 0.51,the glass transition temperature（T g） of polyimides（PIs） decreased from 274 ℃ to 203 ℃ and the Vis-light transmittance of alignment films substantially *** for the alignment properties,the pretilt angle of PI alignment films without rubbing could reach 90° when the content of C6BBC4 was 60% or *** the same time,the alignment stability could meet the industrial *** was considered that the alkoxy spacer,the biphenyl unit and the alkoxy tail may all play important roles in achieving a large pretilt angle even up to 90°,and the introduction of only the alkoxy spacer or alkoxy tail can also improve the pretilt angle,but not by much.

关键词： Polyimide Alignment film Liquid crystal Biphenyl side chain

Application of Current Hapten in the Production of Broad Specificity Antibodies Against Organophosphorus Pesticides

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Agricultural Sciences in China 2008年第11期7卷 1341-1347页

作者： liu Xian-jin YAN Chun-rong liu Yuan YU xiang-yang ZHANG Cun-zheng Food Safety Research and Inspection Center Jiangsu Academy of Agricultural Sciences Nanjing 210014 P.R. China

Diethylphosphono acetic acid （DPA） was used as a current hapten to generate broad specificity polycolonal antibodies against a group of organophosphorus pesticides. Six New Zealand white rabbits were immunized with immunogens synthesized by the active ester method （AEM） or 1-ethyl-3-（3-dimethylaminopropyl）-carbodimide method （EDC）. The titers of antisera reached 25 600 by AEM and 6 400 by EDC, respectively. Polyclonal antibodies raised against DPA were screened and selected for the competitive indirect enzyme-linked immunosorbent assay （CI-ELISA）. A CI-ELISA for DPA was developed with a detection limit of 3.536 ng mL^-1and an I50 value of 0.182 μg mL^-1. The assay specificity was evaluated by obtaining competitive curves for several structurally related compounds as competitors. The antiserum showed high affinities to chlorpyrifos, diazinon, omethoate, parathion-ethyl and profenofos with I50 of 0.12, 0.15, 0.21, 0.88, 0.97 and 2.5 μg mL^-1, respectively. The results indicate that the assay could be a screening tool for quantitation and semiquantitation determination of the above former five organophosphorus pesticides.

关键词： organophosphorus pesticides broad specificity antibody enzyme-linked immunosorbent assay (ELISA)

One-pot-synthesis of novel cinchonine-based phosphites

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Chinese Chemical Letters 2009年第7期20卷 797-799页

作者： Qiao Feng Wang Xue Ying liu xiang yang Qin Xiao Ye Li Sheng Yong Zhang Department of Chemistry Fourth Military Medical University Xi'an 710032 China

Cinchonine was employed as backbone for the synthesis of novel phosphite compounds with diol substituents. These monophosphinites were provided in one pot with the yields ranged from 63% to 75%. Their structures were confirmed by NMR spectroscopy and HRMS. C 2009 Sheng Yong Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cinchona alkaloids Diols Chiral phosphite Asymmetric reaction Ligand

Influence of Steric Hindrance Between Hydrogen Atoms of Linkage Groups and Adjacent Phenyls on Properties of Polyimide

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Chemical Research in Chinese Universities 2012年第5期28卷 926-930页

作者： PANG Yu-wei LUO Long-bo CHEN Yi ZHANG Peng WANG Xu PENG Chao-rong liu xiang-yang State key Laboratory of Polymer Material and Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065P.R.China Sichuan Institute of Atomic Energy Chengdu 610066P.R.China

A diamine monomer 4,4′-methylenedianiline（MDA） was introduced to modify the polyimide of pyromellitic dianhydride（PMDA） and 4,4′-oxydianiline（ODA） by polycondensation. A series of polyamic acids was synthesized from MDA and ODA of different molar ratios with PMDA of sum mole of moles of MDA and ODA, and polyimide films were obtained by thermal imidization. Polyimide（PI） films were characterized by tensile testing, dynamic mechanical analysis（DMA）, thermal gravimetry analysis（TGA）, Fourier transform infrared spectroscopy （FTIR）, wide X-ray diffraction（WAXD） and molecular simulation. With the increase of MDA content, the tensile strength and thermal decomposition temperature remained generally stable compared with those of PMDA/ODA polyimide. Unexpectedly, the glass transition temperature（Tg） and Young＇s modulus increased from 388.7 °C and 2.37 GPa to 408.3 °C and 5.74 GPa, respectively. The results of WAXD and molecular simulation indicate the steric hindrance among hydrogen atoms of the linkage groups and adjacent phenyls enhanced the properties of the polyimide modified with MDA.

关键词： Polyimide Modification Glass transition temperature Steric hindrance

Management of the Recall of Defective Motor Vehicles in China

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China Standardization 2005年第3期50卷 20-23页

作者： liu xiang yang Ying

The Administrative Regulation on the Recall of Defective Motor Vehicles has officially entered into force on October 1st, 2004, which means the management on defective products has made a substantive progress. The enactment and enforcement of the Administrative Regulation has generated active responses in our society and drawn much attention from the automobile industry. Up to March 2005, there have been 15 domestic and foreign auto manufacturers initiating voluntary recalls since the Administrative Regulation on the Recall of Defective Motor Vehicles was issued in March 2004, and 312864 vehicles have been recalled. All the relevant firms, types, models, numbers and the date are as the following table 1.

关键词： SIQ Management of the Recall of Defective Motor Vehicles in China

快速DCT修剪在DSP上的内存访问优化方法

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电子学报 2016年第1期44卷 227-232页

作者：刘项洋许勇安徽师范大学数学计算机科学学院安徽芜湖241000

在本论文中,我们提出一个新的内存访问优化方法以减少由权重因子(在DCT的快速修剪计算图中的余弦系数)和输入点而产生的内存访问量,实现在DSP上的快速DCT修剪.该方法通过两个步骤来减少内存访问量:1.减少权重因子的个数;2.将快速DCT修... 详细信息

在本论文中,我们提出一个新的内存访问优化方法以减少由权重因子(在DCT的快速修剪计算图中的余弦系数)和输入点而产生的内存访问量,实现在DSP上的快速DCT修剪.该方法通过两个步骤来减少内存访问量:1.减少权重因子的个数;2.将快速DCT修剪的计算流程图中两个阶段中的蝴蝶运算单元合并到一个阶段中,从而形成一个高效的蝴蝶运算单元.我们在TI TMSC320C64x DSP上应用该方法来实现修剪FCT.实验结果表明,与传统的实现方法相比,修剪FCT方法在DSP上可以平均减少40%的内存访问量,平均减少48.6%的时钟周期和平均节约32.6%的由存储加权因子导致的内存访问.

关键词：数字信号处理器(DSP) 离散余弦变换(DCT) 内存访问

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云存储系统中基于MSR码的局部性修复编码

北京邮电大学学报 2016年第4期39卷 60-66页

作者：王静梁伟刘向阳杨洋长安大学信息工程学院西安710064 湖南科技大学计算机科学与工程学院湖南湘潭411201 西安通信学院信息服务系西安710106

为了提高分布式云存储系统的存储可靠性和故障节点修复效率,提出一种基于最小存储再生码的局部性修复编码方案.具体地,构造适用于云存储的系统最小存储再生码,以此码为局部码构造局部性修复编码,确保最大距离可分性质和简单修复特性.性... 详细信息

为了提高分布式云存储系统的存储可靠性和故障节点修复效率,提出一种基于最小存储再生码的局部性修复编码方案.具体地,构造适用于云存储的系统最小存储再生码,以此码为局部码构造局部性修复编码,确保最大距离可分性质和简单修复特性.性能分析和仿真结果表明,该局部性修复编码方案可实现云存储系统中多个故障节点的快速修复,具有较低的修复局部性,相对于三副本复制方式和简单再生码,该局部性修复编码方案在存储开销和修复带宽开销方面的性能更优.

关键词：分布式云存储最小存储再生码局部性修复编码