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三倍化复制对白菜花粉特异表达候选基因的影响
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作者 王晓波 马原 +3 位作者 程锋 武剑 梁建丽 王晓武 《中国农业科学》 CAS CSCD 北大核心 2015年第18期3727-3732,共6页
【目的】研究三倍化复制事件后白菜花粉特异表达候选基因的进化情况,为研究白菜的花粉特异表达基因提供理论依据。【方法】利用Syn Orths软件及拟南芥花粉特异表达基因集,通过共线性分析获取白菜中的花粉特异表达候选基因。通过Interpro... 【目的】研究三倍化复制事件后白菜花粉特异表达候选基因的进化情况,为研究白菜的花粉特异表达基因提供理论依据。【方法】利用Syn Orths软件及拟南芥花粉特异表达基因集,通过共线性分析获取白菜中的花粉特异表达候选基因。通过Interpro Scan获取这些候选基因的GO注释,并将这些GO注释划分到与花粉相关的13个大类。然后统计每个GO的基因数占不同拷贝类型基因总数的比例,对不同拷贝类型间进行比较。进一步根据白菜3个亚基因组集,将这些候选基因划分到不同的亚基因组上。通过分析白菜花粉特异表达候选基因中串联重复基因与拟南芥基因的共线性关系,推测这些串联重复基因是在芸薹属特有的三倍化事件之前形成,还是在其之后形成。【结果】通过对拟南芥中的1 651个花粉特异表达基因进行共线性分析,在白菜中总共找到了1 962个花粉特异表达候选基因。拟南芥特异基因集里有182个串联重复基因,而白菜包含了137个串联重复基因。白菜与拟南芥在花粉特异表达基因数目上没有明显差异,因此推测这些基因的大部分拷贝可能在三倍化复制事件后发生了丢失。549个拟南芥花粉特异表达基因在白菜上找不到相应的共线性基因,白菜在进化过程中可能丢失掉了这部分基因。拟南芥花粉特异表达基因中有898个串联重复基因在白菜中对应单或多拷贝的非串联重复基因。在白菜中对应单拷贝基因的拟南芥基因数目为480个,而且所占比例高达53.5%。另外,322个基因在白菜中对应两拷贝,比例约为35.8%。而在白菜中对应三拷贝的拟南芥基因只有96个,大约占总数目的 10.7%。在白菜中,单拷贝和两拷贝的基因数目显著高于三拷贝,这说明三倍化后白菜中大部分花粉特异候选基因发生了丢失,部分两拷贝和三拷贝的基因也可能处于进化选择的过程中。白菜三拷贝基因功能在7个GO分类上的比例高于单拷贝和两拷贝,而白菜两拷贝在所有GO分类上都有分布。白菜花粉特异候选基因中的大部分串联重复基因可能在三倍化事件以后发生了基因丢失,变成了非串联重复基因。也有部分非串联重复基因在三倍化事件之后形成了串联重复基因。【结论】白菜花粉特异候选基因在芸薹属特有的三倍化事件之后处于进化之中,并且三倍化事件可能促进了3种拷贝类型基因的功能差异。 展开更多
关键词 白菜 花粉特异表达 三倍复制 共线性
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靛房汉语施事标记“他”的分布、来源及语法化
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作者 鲁美艳 《怀化学院学报》 2024年第6期94-99,共6页
靛房汉语是指湖南省龙山县靛房镇土家族人所说的汉语。靛房汉语有施事标记,可记作“他”。首先从共时角度探讨“他”的分布特征,然后再从历时角度探寻“他”的来源及语法化过程。通过与土家语施事标记ko35的对比分析,从而得出结论,靛房... 靛房汉语是指湖南省龙山县靛房镇土家族人所说的汉语。靛房汉语有施事标记,可记作“他”。首先从共时角度探讨“他”的分布特征,然后再从历时角度探寻“他”的来源及语法化过程。通过与土家语施事标记ko35的对比分析,从而得出结论,靛房汉语施事标记ko35是受土家语的影响而产生的,是属于语言接触而引发的一种比较特殊的语法化现象。 展开更多
关键词 靛房汉语 施事标记 土家语 复制性语法 语言接触
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模块化复制在房地产生产中的应用
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作者 隋天国 《科技信息》 2013年第2期440-440,443,共2页
随着技术的发展和消费者对产品质量及功能性要求的提高,大规模定制生产逐渐成为当今世界最流行的生产方式之一。本文探讨了模块化复制在房地产开发中应用的背景、基础和优势,总结了模块化复制生产的优势。
关键词 模块复制 房地产目标成本
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分布式数据库复制问题的一种解决方案及应用 被引量:2
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作者 陈宫 牛秦洲 《计算机与现代化》 2011年第11期138-141,共4页
分布式数据库系统中的复制机制有许多优点,但同时也带来一些问题,解决这些问题的方法有很多。针对这些问题,从需求分析、数据分片和分布、异步复制、数据更新、复制模式、数据冲突、查询处理等多方面因素进行考虑,根据实际情况,选择或... 分布式数据库系统中的复制机制有许多优点,但同时也带来一些问题,解决这些问题的方法有很多。针对这些问题,从需求分析、数据分片和分布、异步复制、数据更新、复制模式、数据冲突、查询处理等多方面因素进行考虑,根据实际情况,选择或改进其中的方法,从而形成一种新的解决分布式数据库复制问题的方案,并将其应用到一个实际的出版物发行信息系统之中,较为完善地解决复制问题。 展开更多
关键词 分布式数据库 多主体复制 实体视图复制 单主站点更新 自适应投票选举法
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基于Oracle高级复制的联网售票系统数据库设计 被引量:1
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作者 李振宏 《电脑开发与应用》 2007年第5期62-63,66,共3页
概述了Oracle高级复制技术,介绍了长途客运联网售票系统的功能需求与总体框架,介绍了Oracle高级复制技术在联网售票系统中的应用,并对系统数据库中的存储过程设计进行了讨论,该系统已应用于实际联网售票,性能已达到用户要求。
关键词 高级复制 实体视图复制 联网售票系统
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从语法化视角看马来西亚华语“回”作动态助词的现象 被引量:6
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作者 黄立诗 《现代语文(下旬.语言研究)》 2013年第8期4-6,共3页
本文论述"回"在马来西亚华语里可作动态助词,表示"回复"义。全文列出"回"作为动态助词的多种用例,并将其语法功能和当地高频使用方言广东话及福建话的"返"和"转"作比较。最后通过&qu... 本文论述"回"在马来西亚华语里可作动态助词,表示"回复"义。全文列出"回"作为动态助词的多种用例,并将其语法功能和当地高频使用方言广东话及福建话的"返"和"转"作比较。最后通过"相因生义"和"接触引发的语法化"(Contact-induced grammaticalization)理论说明这种特殊语法现象的出现是"复制性语法化"的产物。 展开更多
关键词 动态助词 回复 相因生义 接触引发的语法 复制性语法
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实体化视图手动刷新在高速公路信息管理系统中的实现
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作者 郭雷勇 龚胡 杨春金 《交通与计算机》 2003年第6期110-111,共2页
文章以重庆高速公路信息管理系统的开发环境为背景,从对实体化视图手动刷新的应用需求出发,结合信息管理系统对其具体实现过程进行了较详细的阐述。
关键词 高速公路 信息管理系统 实体视图复制 自动刷新 PL/SQL 手动刷新 管道函数 关闭句柄函数
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论中国当代建筑的“视觉化复制”现象 被引量:3
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作者 周术 温亚斌 任书斌 《装饰》 CSSCI 北大核心 2011年第11期104-105,共2页
论文从时代背景和建筑学教育这两方面,以建筑学专业的视角,剖析中国当代建筑的"视觉化复制"现象,指出在消费时代形象建构的诉求下,"布扎"教育下的建筑简化使得透视图像成为建筑物的代替品,是产生这一现象的主因。
关键词 中国当代建筑 视觉复制
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直线中的颗粒——张承志作品
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作者 张群 王远舟 《大舞台》 2010年第8期98-99,共2页
作为一个为着理想主义而对现实中熙熙攘攘的文学界发出愤怒和决绝声音的作家,张承志近年来在文学领域的缺席让人对他曾经引发热潮现象借助的文本进行深思,本文主要从文本框架、情感抒发和作者所希望出路中暗含的矛盾进行分析。
关键词 复制化文本 信仰 英雄的矛盾
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台湾电视娱乐节目对大陆的影响 被引量:3
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作者 戢桂荣 《漳州师范学院学报(哲学社会科学版)》 2012年第3期136-140,共5页
电视娱乐节目以颇具人性化的特质带给现代观众相对轻松的观赏体验而受到青睐。台海两岸文化交流日渐频繁,电视节目交流也日益增多,起步较早文化同源的台湾娱乐节目成为大陆直接的参考借鉴对象,其中优秀的主持元素、精良的制作团队、个... 电视娱乐节目以颇具人性化的特质带给现代观众相对轻松的观赏体验而受到青睐。台海两岸文化交流日渐频繁,电视节目交流也日益增多,起步较早文化同源的台湾娱乐节目成为大陆直接的参考借鉴对象,其中优秀的主持元素、精良的制作团队、个性化嘉宾选择,对大陆娱乐节目发展有较大启发和促进作用。台湾娱乐节目制作人带来全新制作观念,使大陆电视娱乐节目发展少走了弯路。正视大陆电视节目娱乐化现状,密切两岸电视文化交流,可以共同提升两岸电视节目的艺术水准。 展开更多
关键词 台湾电视 主持人 嘉宾选择 模式复制 娱乐文交流
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CeO_2/Zn NANOCOMPOSITE COATING BY ELECTRODEPOSITION 被引量:7
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作者 骆心怡 何建平 李顺林 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期161-165,共5页
The nanocomposite coating is obtained by electrochemical deposition of the zinc plating solution with ceria nanoparticles (mean diameter 30 nm). The effect of ceria nanoparticles on the electrodeposited zinc coating i... The nanocomposite coating is obtained by electrochemical deposition of the zinc plating solution with ceria nanoparticles (mean diameter 30 nm). The effect of ceria nanoparticles on the electrodeposited zinc coating is stu died by weight loss test, inductively copuled plasma quantometer (ICP), scanning electron microscopy (SEM) and X ray diffraction (XRD), respectively. It is found that under the same electrodeposition conditions, the corrosion resistance of the nanocomposite coating increases obviously while that of the micron composite coating only improves slightly; The ceria content of the nanocomposite coating is more than that of the micron composite coating. Ceria nanoparticles modify the surface morphology and crystal structure of the zinc matrix in correlation with the increase of corrosion resistance. 展开更多
关键词 composite electrodeposition ceria nanoparticles nanocomposite coating corrosion resistance zinc coating
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Control Effect of Four Kinds of Agents for Anthracnose in Autumn Greenhouse Cowpea
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作者 彭昌家 白体坤 +5 位作者 丁攀 冯礼斌 刘怡欣 杨宇衡 朱成 陈丹 《Agricultural Science & Technology》 CAS 2016年第10期2324-2328,共5页
In order to mitigate the occurrence and damage of cowpea anthracnose and reduce the chemical pesticide consumption, residue and environmental pollution, the methods of forecasting, randomized block design and statisti... In order to mitigate the occurrence and damage of cowpea anthracnose and reduce the chemical pesticide consumption, residue and environmental pollution, the methods of forecasting, randomized block design and statistical analysis were conducted to study the control effect of biopesticide chitosan, biochemical compound Prochloraz-Chitosan and chemical pesticides difenoconazole and thifluzamide by field efficacy trials. The results showed that under serious occurrence of anthracnose in autumn greenhouse cowpea, when the 2% chJtosan AS (2 250 g/hm^2), 46% Prochloraz-Chitosan EW (450 g/hm^2), 10% difenoconazole WG (900 g/hm^2, CK) or 24% thifluzamide SC (360 ml/hm^2) were applied three times with an interval of 5-8 d, the control efficiency on day 7, 14 and 20 reached 83%, 78% and 73%, respectively. No significant difference was found in control efficiency among the four kinds of agents. These four kinds of agents, especially chitosan and Prochloraz-Chitosan, could be used as ideal agents for controlling anthracnose, as well as for modern agricultural demonstration zones, pollution-free agricultural products, green agricultural products and organic agricultural products,thereby meeting the develop- ment needs of 'modern agriculture, green agriculture, organic agriculture and ecological agriculture. 展开更多
关键词 Cowpea anthracnose Biopesticide CHITOSAN Biochemical compound Prochloraz-Chitosan Chemical pesticide DIFENOCONAZOLE THIFLUZAMIDE Control efficacy
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对射频掩护雷达的应答式干扰研究 被引量:2
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作者 孟超普 王秀锦 杨爱平 《舰船电子对抗》 2019年第2期7-13,共7页
给出了射频掩护雷达的两种基本波形,对紧贴式射频掩护波形的抗瞬时测频性能和数字射频存储性能进行了分析,针对上述低截获概率(LPI)性能,设计了3种改进应答式干扰方法:样本预存储干扰、间歇采样干扰和信道化前沿循环复制干扰,分别对3种... 给出了射频掩护雷达的两种基本波形,对紧贴式射频掩护波形的抗瞬时测频性能和数字射频存储性能进行了分析,针对上述低截获概率(LPI)性能,设计了3种改进应答式干扰方法:样本预存储干扰、间歇采样干扰和信道化前沿循环复制干扰,分别对3种应答式干扰进行了干扰设计、主要参数设定和工程应用的分析。 展开更多
关键词 射频掩护雷达 瞬时测频接收机 数字射频存储器 样本预存储干扰 间歇采样干扰 信道前沿循环复制干扰
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APPLICATION OF HYBRID AERO-ENGINE MODEL FOR INTEGRATED FLIGHT/PROPULSION OPTIMAL CONTROL 被引量:4
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作者 王健康 张海波 +1 位作者 孙健国 李永进 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第1期16-24,共9页
The real-time capability of integrated flight/propulsion optimal control (IFPOC) is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gr... The real-time capability of integrated flight/propulsion optimal control (IFPOC) is studied. An appli- cation is proposed for IFPOC by combining the onboard hybrid aero-engine model with sequential quadratic pro- gramming (SQP). Firstly, a steady-state hybrid aero-engine model is designed in the whole flight envelope with a dramatic enhancement of real-time capability. Secondly, the aero-engine performance seeking control including the maximum thrust mode and the minimum fuel-consumption mode is performed by SQP. Finally, digital simu- lations for cruise and accelerating flight are carried out. Results show that the proposed method improves real- time capability considerably with satisfactory effectiveness of optimization. 展开更多
关键词 integrated flight/propulsion optimal control AERO-ENGINE hybrid model performance seeking con- trol sequential quadratic programming
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广西汉、壮语方言“给予”义语素的两种特殊用法 被引量:2
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作者 王盈盈 覃东生 《百色学院学报》 2018年第6期29-35,共7页
文章描写了广西汉、壮语方言"给予"义语素两种特殊的对象格标记用法,并对其产生的过程进行了讨论。主要观点是:(1)对象格标记的语法化过程为"给予动词>与格标记>对象格标记1>对象格标记2";(2)汉语方言&qu... 文章描写了广西汉、壮语方言"给予"义语素两种特殊的对象格标记用法,并对其产生的过程进行了讨论。主要观点是:(1)对象格标记的语法化过程为"给予动词>与格标记>对象格标记1>对象格标记2";(2)汉语方言"给予"义语素的对象格标记用法和"VP+Pre_给+NP"语序均源自壮语的扩散。前者是通过"复制性语法化"对"ha?~3"的对象格标记用法及其语法化路径进行复制的结果;后者是对壮语"VP+ha?~3+NP"语序进行复制的产物。 展开更多
关键词 “给予”义语素 复制性语法 语序复制
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“源方言”与马来西亚华语的形成——以补语标记“到”为例 被引量:3
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作者 齐环玉 《云南师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2020年第2期73-83,共11页
文章归纳了马来西亚华语的形成过程及其特点,指出“源方言”(尤其是粤方言)是对其形成和发展影响最大的因素,并以马来西亚华语中最具特色的补语标记“到”为例,归纳出“到”的9种用法,绘制语义图模型,对比“到”在马来西亚华语、普通话... 文章归纳了马来西亚华语的形成过程及其特点,指出“源方言”(尤其是粤方言)是对其形成和发展影响最大的因素,并以马来西亚华语中最具特色的补语标记“到”为例,归纳出“到”的9种用法,绘制语义图模型,对比“到”在马来西亚华语、普通话、汉语三大“源方言”以及现代白话中的用法分布,描写“到”在标准语和方言中的不同语法化路径,最后运用“复制语法化”理论,得出马来西亚华语补语标记“到”来源于粤方言中的“到(倒)”,从而阐明“源方言”,尤其是粤方言,对马来西亚华语的重要影响。 展开更多
关键词 “到” 马来西亚华语 补语 语义图 复制语法
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Improving Image Copy-Move Forgery Detection with Particle Swarm Optimization Techniques 被引量:7
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作者 SHI Wenchang ZHAO Fei +1 位作者 QIN Bo LIANG Bin 《China Communications》 SCIE CSCD 2016年第1期139-149,共11页
Copy-Move Forgery(CMF) is one of the simple and effective operations to create forged digital images.Recently,techniques based on Scale Invariant Features Transform(SIFT) are widely used to detect CMF.Various approach... Copy-Move Forgery(CMF) is one of the simple and effective operations to create forged digital images.Recently,techniques based on Scale Invariant Features Transform(SIFT) are widely used to detect CMF.Various approaches under the SIFT-based framework are the most acceptable ways to CMF detection due to their robust performance.However,for some CMF images,these approaches cannot produce satisfactory detection results.For instance,the number of the matched keypoints may be too less to prove an image to be a CMF image or to generate an accurate result.Sometimes these approaches may even produce error results.According to our observations,one of the reasons is that detection results produced by the SIFT-based framework depend highly on parameters whose values are often determined with experiences.These values are only applicable to a few images,which limits their application.To solve the problem,a novel approach named as CMF Detection with Particle Swarm Optimization(CMFDPSO) is proposed in this paper.CMFD-PSO integrates the Particle Swarm Optimization(PSO) algorithm into the SIFT-based framework.It utilizes the PSO algorithm to generate customized parameter values for images,which are used for CMF detection under the SIFT-based framework.Experimental results show that CMFD-PSO has good performance. 展开更多
关键词 copy-move forgery detection SIFT region duplication digital image forensics
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Facile synthesis of Sb@Sb2O3/reduced graphene oxide composite with superior lithium-storage performance 被引量:4
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作者 ZHOU Xiao-zhong LU He-jie +2 位作者 TANG Xing-chang ZENG Ya-ping YU Xin 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第6期1493-1502,共10页
Sb-based materials have been considered one of the most promising anode electrode materials for lithium-ion batteries,whereas they were commonly synthesized through time-consuming and costly processes.Here,Sb@Sb2O3/re... Sb-based materials have been considered one of the most promising anode electrode materials for lithium-ion batteries,whereas they were commonly synthesized through time-consuming and costly processes.Here,Sb@Sb2O3/reduced graphene oxide(Sb@Sb2O3/rGO)composite was successfully synthesized by a facile one-pot chemical method at ambient temperature.Based on the XRD and TGA analysis,the mass fractions of Sb and Sb2O3 in the Sb@Sb2O3/rGO composite are ca.34.05%and 26.6%,respectively.When used as an alternative electrode for lithium ion batteries,a high reversible capacity of 790.9 mA·h/g could be delivered after 200 cycles with the capacity retention of 93.8%at a current density of 200 mA/g.And a capacity of 260 mA·h/g could be maintained even at 2000 mA/g.These excellent electrochemical properties can be attributed to its well-constructed nanostructure.The Sb and Sb2O3 particles with size of 10 nm were tightly anchored on rGO sheets through electronic coupling,which could not only alleviate the stress induced by the volume expansion,suppress the aggregation of Sb and Sb2O3 particles,but also improve the electron transfer ability during cycling. 展开更多
关键词 Sb@Sb2O3/rGO composite synthesis electrochemical performance lithium-ion batteries
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Combination of small interfering RNAs mediates greater inhibition of human hepatitis B virus replication and antigen expression 被引量:9
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作者 陈喆 许则丰 +3 位作者 叶景佳 姚航平 郑树 丁佳逸 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE EI CAS CSCD 2005年第4期236-241,共6页
Objectives: To evaluate the inhibitory effect mediated by combination of small interfering RNAs (siRNAs) targeting different sites of hepatitis B virus (HBV) transcripts on the viral replication and antigen expression... Objectives: To evaluate the inhibitory effect mediated by combination of small interfering RNAs (siRNAs) targeting different sites of hepatitis B virus (HBV) transcripts on the viral replication and antigen expression in vitro. Methods: (1) Seven siRNAs targeting surface (S), polymerase (P) or precore (PreC) region of HBV genome were designed and chemically synthesized. (2) HBV-producing HepG2.2.15 cells were treated with or without siRNAs for 72 h. (3) HBsAg and HBeAg in the cell culture medium were detected by enzyme-linked immunoadsorbent assay. (4) Intracellular viral DNA was quantified by real-time PCR (Polymerase Chain Reaction). (5) HBV viral mRNA was reverse transcribed and quantified by real-time PCR. (6) The change of cell cycle and apoptosis was determined by flow cytometry. Results: Our data demonstrated that synthetic small interfering RNAs (siRNAs) targeting S and PreC gene could efficiently and specifically inhibit HBV replication and antigen expression. The ex- pression of HBsAg and HBeAg and the replication of HBV could be specifically inhibited in a dose-dependent manner by siRNAs. Furthermore, our results showed that the combination of siRNAs targeting various regions could inhibit HBV replication and antigen expression in a more efficient way than the use of single siRNA at the same final concentration. No apoptotic change was observed in the cell after siRNA treatment. Conclusion: Our results demonstrated that siRNAs exerted robust and specific inhibi- tion on HBV replication and antigen expression in a cell culture system and combination of siRNAs targeting different regions exhibited more potency. 展开更多
关键词 Hepatitis B virus Combination of siRNAs HBV replication Antigen expression
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A composite particle swarm algorithm for global optimization of multimodal functions 被引量:7
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作者 谭冠政 鲍琨 Richard Maina Rimiru 《Journal of Central South University》 SCIE EI CAS 2014年第5期1871-1880,共10页
During the last decade, many variants of the original particle swarm optimization (PSO) algorithm have been proposed for global numerical optimization, hut they usually face many challenges such as low solution qual... During the last decade, many variants of the original particle swarm optimization (PSO) algorithm have been proposed for global numerical optimization, hut they usually face many challenges such as low solution quality and slow convergence speed on multimodal function optimization. A composite particle swarm optimization (CPSO) for solving these difficulties is presented, in which a novel learning strategy plus an assisted search mechanism framework is used. Instead of simple learning strategy of the original PSO, the proposed CPSO combines one particle's historical best information and the global best information into one learning exemplar to guide the particle movement. The proposed learning strategy can reserve the original search information and lead to faster convergence speed. The proposed assisted search mechanism is designed to look for the global optimum. Search direction of particles can be greatly changed by this mechanism so that the algorithm has a large chance to escape from local optima. In order to make the assisted search mechanism more efficient and the algorithm more reliable, the executive probability of the assisted search mechanism is adjusted by the feedback of the improvement degree of optimal value after each iteration. According to the result of numerical experiments on multimodal benchmark functions such as Schwefel, Rastrigin, Ackley and Griewank both with and without coordinate rotation, the proposed CPSO offers faster convergence speed, higher quality solution and stronger robustness than other variants of PSO. 展开更多
关键词 particle swarm algorithm global numerical optimization novel learning strategy assisted search mechanism feedbackprobability regulation
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