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Expression patterns of the rice class I metallothionein gene family in response to lead stress in rice seedlings and functional complementation of its members in lead-sensitive yeast cells

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Chinese Science Bulletin 2007年第16期52卷 2203-2209页

作者： XU YuFeng ZHOU GongKe ZHOU Lu LI yiqin liu JinYuan Laboratory of Molecular Biology and Protein Science Key Laboratory of the Ministry of Education Department of Biological Sciencesand Biotechnology Tsinghua University Beijing 100084 China

Metallothioneins (MTs) are a group of low molecular mass and cysteine-rich proteins that can chelate heavy-metal ions. In this paper,Northern blot analysis was used to investigate the influence of lead stress on the expression patterns of 10 rice class I MT genes (OsMT-Is) in rice seedlings. With the ex-ception of OsMT-I-3b,the data demonstrate dynamic changes of 9 OsMT-I transcripts in response to Pb2+ treatment in rice seedling roots. Of these genes,transcription of OsMT-I-1a,OsMT-I-1b,OsMT-I-2c,OsMT-I-4a,OsMT-I-4b and OsMT-I-4c increased significantly,while transcription of OsMT-I-2a and OsMT-I-3a increased marginally. In contrast,the expression of OsMT-I-2b was inhibited. Pb2+ induced the expression of 6 OsMT-I genes in seedling shoots,but had no obvious effects on the expression of OsMT-I-1a,OsMT-I-1b,OsMT-I-4a and OsMT-I-4b. All the 10 OsMT-Is had enhanced lead tolerance when heterologously expressed in lead-sensitive yeast mutant cells. These results provide an expression profile of the rice MT gene family in response to Pb2+ stress in rice seedlings and demonstrate in-creased lead tolerance in sensitive yeast mutant cells expressing OsMT-Is. This study lays a foundation for further analysis of the role of the rice MT gene family in respond to Pb2+ stress.

关键词：水稻金属硫蛋白基因表达铅酵母细胞

Prediction and Optimization of the Thermal Properties of TiO_(2)/Water Nanofluids in the Framework of a Machine Learning Approach

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Fluid Dynamics & Materials Processing 2023年第8期19卷 2181-2200页

作者： Jiachen Li Wenlong Deng Shan Qing yiqin liu Hao Zhang Min Zheng Sate Key Laboratory of Complex Nonferrous Clean Utilization Kunming University of Science and TechnologyKunming650093China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China Jiangxi Guoxing Intelligent Energy Co. Ganzhou330300China Faculty of Media and Information Engineering Yunnan Open UniversityKunming650500China

In this study,comparing multiple models of machine learning,a multiple linear regression(MLP),multilayer feed-forward artificial neural network(BP)model,and a radial-basis feed-forward artificial neural network(RBF-BP)model are selected for the optimization of the thermal properties of TiO_(2)/water *** particular,the least squares support vector machine(LS-SVM)method and radial basis support vector machine(RB-SVM)method are ***,curve fitting is performed by means of multiple linear regression in order to obtain bivariate correlation functions for thermal conductivity and viscosity of the *** the aforementioned models are used for a predictive analysis of the dependence of its thermal conductivity and viscosity on temperature and volume *** results show that the least squares support vector machine(LS-SVM)has a prediction accuracy higher than the other *** model predicts the thermal conductivity of TiO_(2)/water MSE=1.0853×10^(-6),R2=0.99864,MAE=0.00092,RMSE=0.00104,and the viscosity of TiO_(2)/water MSE=8.1397×10^(-6),R2=0.99995,MAE=0.00074,RMSE=0.0009.

关键词： Nanofluids viscosity thermal conductivity machine learning predictive modeling

Stability and Thermal Property Optimization of Propylene Glycol-Based MWCNT Nanofluids

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Fluid Dynamics & Materials Processing 2023年第9期19卷 2399-2416页

作者： Xi Wang Shan Qing Zhumei Luo yiqin liu Zichang Shi Jiachen Li Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China Faculty of Media and Information Engineering Yunnan Open UniversityKunming650093China

Propylene glycol-based MWCNT(multi-walled carbon nanotubes)nanoﬂuids were prepared in the framework of a two-step method and by using a suitable PVP(polyvinyl pyrrolidone)*** BBD(Box-Behnken design)model was exploited to analyze 17 sets of experiments and examine the sensitivity of the absorbance to three parameters,namely the concentration of MWCNT,the SN ratio(mass ratio of carbon nanotubes to sur-factants)and the sonication *** results have revealed that,while the SN ratio and concentration of MWCNT have a strong effect on the absorbance,the inﬂuence of the sonication time is less *** sta-tistical method of analysis of variance(ANOVA)was further used to determine the F-and p-values of the *** experiments were run to validate this *** sample 2 was found to display the greatest absorbance,it was selected for stability monitoring as well as thermal conductivity and viscosity *** sample has been found to be stable;the viscosity decreased with increasing temperature;the addition of MWCNT nano-particles was more effective in improving the thermal conductivity of propylene glycol than other methods in the ***,the MWCNT nanoﬂuid based on propylene glycol exhibited higher thermal conductivity at low temperatures.

关键词： Propylene glycol thermal conductivity response surface methodology stability viscosity

Research on Pantograph and Overhead Contact System′s Simulation of High Speed Railway and Comparison of Three Calculation Methods by Finite Element Method

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International Journal of Plant Engineering and Management 2021年第1期26卷 46-56页

作者： PANG Zhining liu Yin WANG Dongming liu yiqin CHEN Yangyang Design&Research Institute China Railway Electrification Bureau(Group)Co.LTD.Beijing100166China

This study relies on the project about Jining to Tongliao railway electrification reconstruction *** dynamic simulation model of the pantograph-OCS(overhead contact system)suitable for Jitong project is designed,according to the corresponding numerical calculation method and ***,We establish the pantograph and catenary′s BIM models,and the parameters related to the dynamic simulation of the pantograph system are attached to the BIM ***,the BIM model is transformed into a mechanical analysis model,which is input into the dynamic simulation software of *** rationality of the design scheme of the pantograph system is verified through simulation.

关键词： pantograph-OCS simulation finite element

Zinc up-regulated the expression of the rice metallonthionein gene family and enhanced the zinc tolerance of yeast cells

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Progress in Natural Science:Materials International 2007年第10期17卷 1166-1171页

作者： Xu Yufeng, Zhou Gongke, Li yiqin and liu Jinyuan(Laboratory of Molecular Biology and Protein Science Laboratory of the Ministry of Education, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China) Laboratory of Molecular Biology and Protein Science Laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Northern blot and functional complementation assay were employed to analyze the effects of zinc on expression of ten rice metallothionein genes (OsMT-Is) in rice seedlings and the growth of yeast cells transformed with OsMT-Is. Northern blot revealed that in shoots of the rice seedlings treated with different Zn2+concentrations, expression of most members of OsMT-I family was increased, except the type 4 OsMT-Is (OsMT-I-4a, 4b and 4c). In roots, Zn2+significantly increased the transcription of OsMT-I-1b and OsMT-I-2c, but reduced the trascription of OsMT-I-1a and OsMT-I-3a. When these ten cDNAs were heterologously expressed in zinc sensitive yeast mutant, all transgenic yeasts showed increased tolerance to Zn2+, and zinc accumulation in these yeast cells also increased. These indicated that OsMT-I family members might respond to extra Zn2+, and they could enhance Zn2+ tolerance of cells by direct binding Zn2+.

关键词： rice metallothionein induced expression Zn2+ tolerance.

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图书封面设计的导向价值与实现路径探析

出版科学 2024年第6期32卷 59-66页

作者：刘艺琴武汉大学新闻与传播学院武汉430072

图书的精神属性决定了图书封面设计具有很强的导向性,包括政治导向、文化导向和审美导向三个维度。由于设计要素选取不当、设计要素组合失当、设计风格模板化等原因,导致当前我国图书封面设计存在一些导向问题。封面设计人员应巧妙利用... 详细信息

图书的精神属性决定了图书封面设计具有很强的导向性,包括政治导向、文化导向和审美导向三个维度。由于设计要素选取不当、设计要素组合失当、设计风格模板化等原因,导致当前我国图书封面设计存在一些导向问题。封面设计人员应巧妙利用图形、色彩、文字设计“三要素”,提升图书封面设计的导向价值。

关键词：图书封面设计平面设计“三要素” 导向

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我国图书植入式广告存在的问题及规制思考

出版科学 2015年第4期23卷 22-25页

作者：刘艺琴武汉大学新闻与传播学院武汉430072

图书植入式广告是近年来引起社会各界普遍热议和行业主管部门重点关注的一种广告形态。本文分析中国图书植入式广告存在问题,并提出解决问题的思路建议。

关键词：图书植入式广告规制措施

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图书广告如何做活市场?

出版发行研究 2006年第1期 33-36页

作者：刘艺琴刘艺武汉大学湖北教育出版社

当前,我们所面临的市场竞争越来越残酷,各出版社都在使出浑身解数试图搞好图书营销。因此,加强图书广告战略的研究对增强图书在市场上的竞争力有着积极的意义。同时从长远的发展考虑,重视图书的广告宣传对提高出版企业的整体形象与品牌... 详细信息

当前,我们所面临的市场竞争越来越残酷,各出版社都在使出浑身解数试图搞好图书营销。因此,加强图书广告战略的研究对增强图书在市场上的竞争力有着积极的意义。同时从长远的发展考虑,重视图书的广告宣传对提高出版企业的整体形象与品牌知名度也有着重要的作用。随着市场竞争的加剧,广告宣传在图书销售中的作用将会日益凸显。

关键词：图书广告市场竞争广告宣传品牌知名度图书营销广告战略整体形象出版企业图书销售出版社

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光纤双干涉在线绝对测量技术研究

仪器仪表学报 2013年第2期34卷 268-274页

作者：马森谢芳刘义秦李恒鹤北京交通大学理学院物理系北京100044

研究了一种新的兼融低相干干涉和高相干干涉的光纤在线绝对测量技术,可对能转换成位移变化的静态及准静态任意物理量进行测量。利用宽带光谱光源作为光源,以及光纤光栅只反射布拉格波长的特性,使光纤迈克尔逊干涉仪同时工作于低相干干... 详细信息

研究了一种新的兼融低相干干涉和高相干干涉的光纤在线绝对测量技术,可对能转换成位移变化的静态及准静态任意物理量进行测量。利用宽带光谱光源作为光源,以及光纤光栅只反射布拉格波长的特性,使光纤迈克尔逊干涉仪同时工作于低相干干涉和高相干干涉状态。用低相干干涉信号决定被测量的幅值,使测量的最大跨距不受光波波长限制,并且实现绝对测量;同时,用高相干干涉信号测量被测量的量值,使测量结果保持高相干干涉测量的高精度。利用高相干干涉信号对环境干扰进行修正,使该测量技术适合在线测量。分别研究并实验了单光源光纤测量系统以及由双光源组成的复合光源光纤测量系统,利用这两种系统对位移进行测量,测量结果的线性相关性分别为0.996和0.999 9,测量量程均为6 mm,均可对0～6 mm范围内任意跨距的位移进行测量。

关键词：干涉测量光纤传感器在线测量绝对测量