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“Junk”DNA的研究进展
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作者 董玉玮 《科技资讯》 2007年第27期4-5,共2页
真核生物基因组中存在着大量的非编码序列,这些"Junk"DNA所发挥的重要功能正逐渐被人们所了解。本文综述了真核生物基因组中"Junk"DNA的构成和功能,并对未来进一步的研究作了展望。
关键词 "junk"DNA 构成 功能 发展
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从Schrodinger的微型密码到Junk DNA编码关系的探索
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作者 罗辽复 《物理通报》 2005年第3期3-6,共4页
60年前埃尔温·薛定谔在英国都柏林三一学院高等研究院作了著名的题为<生命是什么?>的系列讲演,并随即整理成小册子,以<生命是什么?活细胞的物理观>为书题,在剑桥大学出版社出版.这本小册子在生物学界极负盛名,被称为&q... 60年前埃尔温·薛定谔在英国都柏林三一学院高等研究院作了著名的题为<生命是什么?>的系列讲演,并随即整理成小册子,以<生命是什么?活细胞的物理观>为书题,在剑桥大学出版社出版.这本小册子在生物学界极负盛名,被称为"分子生物学中的<汤姆叔叔的小屋>",意思是指这本书可看作分子生物学的开端,好像<汤姆叔叔的小屋>是黑奴文学的开端一样.在那个传统生物学占统治地位的年代,"这本书的出版给生物学增添了异彩".很多在生物学中作出过重要贡献的科学家如霍尔丹(Holdane)和克里克(Crick),都承认受到过这位具有高度独创性的缜密思维的物理学家在本书中提出的许多观念的影响;事实上,沃森(Watson)和克里克就是在薛定谔的影响下去分析遗传物质DNA的.正如彭罗斯(Penrose)1991年在本书前言中说"这本书一定会跻身于本世纪最有影响的科学著作之列,它代表了一位物理学家力图理解真正的生命之谜的有力尝试.这位物理学家的深刻洞察力在很大程度上已经改变了人们对世界组成的理解". 展开更多
关键词 分子生物学 《生命是什么?》 遗传密码 junk DNA 编码关系
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Junk DNA分子序列碱基组合的频率分析
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作者 李海 王正荣 《生物医学工程学杂志》 EI CAS CSCD 北大核心 1995年第3期224-228,共5页
JunkDNA分子序列中很大部分由简单序列的重复序列组成,并且呈现较大的个体差异.这些简单序列及其重复序列的频率分布可能具有某种指征作用.本文拟就简单序列的复合频率,提出了一种复合分布模型,以及模式选择的一种标准,用... JunkDNA分子序列中很大部分由简单序列的重复序列组成,并且呈现较大的个体差异.这些简单序列及其重复序列的频率分布可能具有某种指征作用.本文拟就简单序列的复合频率,提出了一种复合分布模型,以及模式选择的一种标准,用以检验JunkDNA分子序列的统计性质.本文就几种具体的假设,给出了模型的概率分布和参数估计式. 展开更多
关键词 junk DNA 简单序列 重复序列 频率分布
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Junk band recovery for hyperspectral image based on curvelet transform
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作者 孙蕾 罗建书 《Journal of Central South University》 SCIE EI CAS 2011年第3期816-822,共7页
Under consideration that the profiles of bands at close wavelengths are quite similar and the curvelets are good at capturing profiles, a junk band recovery algorithm for hyperspectral data based on curvelet transform... Under consideration that the profiles of bands at close wavelengths are quite similar and the curvelets are good at capturing profiles, a junk band recovery algorithm for hyperspectral data based on curvelet transform is proposed. Both the noisy bands and the noise-free bands are transformed via curvelet band by band. The high frequency coefficients in junk bands are replaced with linear interpolation of the high frequency coefficients in noise-flee bands, and the low frequency coefficients remain the same to keep the main spectral characteristics from being distorted. Jutak bands then are recovered after the inverse curvelet transform. The performance of this method is tested on the hyperspectral data cube obtained by airborne visible/infrared imaging spectrometer (AVIRIS). The experimental results show that the proposed method is superior to the traditional denoising method BayesShrink and the art-of-state Curvelet Shrinkage in both roots of mean square error (RMSE) and peak-signal-to-noise ratio (PSNR) of recovered bands. 展开更多
关键词 hyperspectral image curvelet transform junk band denosing
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除砂处理的全新理念——The Junk Trap除砂装置
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作者 李玉峰 《中华纸业》 CAS 北大核心 2009年第18期111-111,共1页
在除砂处理的应用上,业界一直没有统一的标准和措施来解决这个问题。但是除砂处理所导致的一系列诸如闸板的磨损、闸板被撞弯以及阀门的堵塞等问题一直很常见,特别是在旋分除砂器中介质旋转所引起的阀门闸板和管道的磨损等问题十分严重。
关键词 砂处理 junk 除砂装置 TRAP 闸板 除砂器 磨损 阀门
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Relationship between Shanghai Sand Junk Culture and the Development of Shanghai International Shipping Center
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作者 Qunzhen QU Siyu GAO 《Meteorological and Environmental Research》 CAS 2021年第5期31-34,共4页
From the three aspects of material culture,institutional culture and spiritual culture,the connotation and development of Shanghai sand junk culture and the position in Shanghai shipping culture were analyzed,and the ... From the three aspects of material culture,institutional culture and spiritual culture,the connotation and development of Shanghai sand junk culture and the position in Shanghai shipping culture were analyzed,and the relationship between Shanghai sand junk culture and the development of Shanghai International Shipping Center was studied according to the construction target and the soft power demand of Shanghai International Shipping Center. 展开更多
关键词 Sand junk culture Shanghai International Shipping Center Shipping culture RELATIONSHIP
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Analysis of the Functions of Shanghai Sand Junk Culture in Modern Times
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作者 Binbin HE Qunzhen QU 《Meteorological and Environmental Research》 CAS 2021年第3期50-52,共3页
From the aspects of the spiritual core of modern Shanghai sand junk culture,the influence of modern sand junk culture on the urbanization process of Shanghai,and the inheritance of modern Shanghai sand junk culture,th... From the aspects of the spiritual core of modern Shanghai sand junk culture,the influence of modern sand junk culture on the urbanization process of Shanghai,and the inheritance of modern Shanghai sand junk culture,the functions of modern Shanghai sand junk culture were analyzed to provide certain reference for the application and inheritance of sand junk culture in the new era. 展开更多
关键词 Modern Shanghai Sand junk culture Function
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Study on the Relationship between Shanghai Sand Junk Culture and Marine Culture
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作者 Qunzhen QU Yunting WEI 《Meteorological and Environmental Research》 CAS 2022年第2期50-52,共3页
Shanghai sand junk culture and marine culture were introduced from the four aspects of culture(physics,institution,behavior and mentality),and their relation was analyzed.The results show that there is a generic relat... Shanghai sand junk culture and marine culture were introduced from the four aspects of culture(physics,institution,behavior and mentality),and their relation was analyzed.The results show that there is a generic relationship between marine culture and Shanghai sand junk culture.Shanghai sand junk culture reflects the marine culture in a specific period and enriches the connotation of marine culture.Marine culture is the foundation of Shanghai sand junk culture,and provides new opportunities for the sustainable development of Shanghai sand junk culture.Therefore,the study of the relationship between Shanghai sand junk culture and marine culture is beneficial for the two to promote each other,and lays a solid cultural foundation for the realization of"maritime power". 展开更多
关键词 Shanghai sand junk culture Marine culture RELATIONSHIP
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Study on the Relationship between Shanghai Sand Junk Culture and Shanghai Urban Culture
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作者 Qunzhen QU Hongmei ZHENG 《Meteorological and Environmental Research》 CAS 2021年第3期38-40,共3页
From material,spiritual,institutional and behavioral aspects,Shanghai sand junk culture and Shanghai urban culture were studied,and the relationship between the two was analyzed.It is found that there are similarities... From material,spiritual,institutional and behavioral aspects,Shanghai sand junk culture and Shanghai urban culture were studied,and the relationship between the two was analyzed.It is found that there are similarities and individualities between Shanghai sand junk culture and Shanghai urban culture,and the two are closely compatible. 展开更多
关键词 Shanghai sand junk culture Shanghai urban culture RELATIONSHIP
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Study on Sand Junk Culture in Shanghai during the Ming and Qing Dynasties
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作者 Qunzhen QU Xi KUANG 《Meteorological and Environmental Research》 CAS 2021年第4期21-23,共3页
Starting from the perspective of shipping culture,sand junk culture in Shanghai during the Ming and Qing Dynasties was studied from the aspects of material,system,behavior and mentality.It is found that the change and... Starting from the perspective of shipping culture,sand junk culture in Shanghai during the Ming and Qing Dynasties was studied from the aspects of material,system,behavior and mentality.It is found that the change and development of sand junk culture in Shanghai during the Ming and Qing Dynasties are closely related to the convenient shipping conditions and economic activities."Sand junk culture"runs through the development of shipping industry in Shanghai area,reflecting a pioneering and enterprising,compatible and inclusive spirit. 展开更多
关键词 Ming and Qing Dynasties Sand junk culture Shipping culture Shipping industry
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小议junk mail
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作者 龙毛忠 《语言教育》 1993年第12期11-12,共2页
笔者在国外进修期间发现了一个有趣的现象:信箱里除了信件、杂志以外,还有不少“不速之客”不期而至,那就是 junk mail, 即一些没有注明收件人姓名、住址的宣传品。这些东西来源不一,五花八门:有当地报纸、有传教的小册子、有生产厂家... 笔者在国外进修期间发现了一个有趣的现象:信箱里除了信件、杂志以外,还有不少“不速之客”不期而至,那就是 junk mail, 即一些没有注明收件人姓名、住址的宣传品。这些东西来源不一,五花八门:有当地报纸、有传教的小册子、有生产厂家的产品介绍(有的甚至还附有样品如洗发香波、眼镜套等)、有商店的商品厂告及其价目表。 展开更多
关键词 收件人姓名 洗发香波 当地报纸 junk mail 招聘启事 商品广告 本地新闻 牛皮纸袋 免费报纸 个人权力
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Watertight,Bulkhead Technology of Chinese Junks
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《ChinAfrica》 2019年第3期60-61,共2页
Inscribed on the List of Intangible Cultural Heritage in Need of Urgent Safeguarding in 2010.
关键词 Watertight BULKHEAD TECHNOLOGY CHINESE junks
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Love Makes Their Life Worth——Story about Shao Junke's help for the handicapped
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作者 ZHU ZHENQIANG 《The Journal of Human Rights》 2008年第2期24-25,共2页
The handicapped, a special group in society, usually encounter many difficulties in employment, marriage, and daily life.Some difficulties are what they cannot conquer by themselves. It is also not easy for them to in... The handicapped, a special group in society, usually encounter many difficulties in employment, marriage, and daily life.Some difficulties are what they cannot conquer by themselves. It is also not easy for them to integrate into society. However, if there is a person who helps the hand- icapped find a job, build up confidence and make their life worth; if there is a person who helps them set up their families and incorporate in a harmonious community; 展开更多
关键词 work Story about Shao junke’s help for the handicapped Love Makes Their Life Worth
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Analyse 1-800-GOT-JUNK——Low Carbon Recycle Business
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作者 Li Yi 《致富时代(下半月)》 2010年第6期37-38,共2页
关键词 二氧化碳 再循环 工业生产 公民权
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A Solution to the C-Value Paradox and the Function of Junk DNA: The Genome Balance Hypothesis 被引量:2
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作者 Michael Freeling Jie Xu +1 位作者 Margaret Woodhouse Damon Lisch 《Molecular Plant》 SCIE CAS CSCD 2015年第6期899-910,共12页
The Genome Balance Hypothesis originated from a recent study that provided a mechanism for the phenom- enon of genome dominance in ancient polyploids: unique 24nt RNA coverage near genes is greater in genes on the re... The Genome Balance Hypothesis originated from a recent study that provided a mechanism for the phenom- enon of genome dominance in ancient polyploids: unique 24nt RNA coverage near genes is greater in genes on the recessive subgenome irrespective of differences in gene expression. 24nt RNAs target transposons. Transposon position effects are now hypothesized to balance the expression of networked genes and pro- vide spring-like tension between pericentromeric heterochromatin and microtubules. The balance (coordi- nation) of gene expression and centromere movement is under selection. Our hypothesis states that this balance can be maintained by many or few transposons about equally well. We explain known balanced dis- tributions of junk DNA within genomes and between subgenomes in allopolyploids (and our hypothesis passes "the onion test" for any so-called solution to the C-value paradox), importantly, when the allotetra- ploid maize chromosomes delete redundant genes, their nearby transposons are also lost; this result is ex- plained if transposons near genes function. The Genome Balance Hypothesis is hypothetical because the position effect mechanisms implicated are not proved to apply to all junk DNA, and the continuous nature of the centromeric and gene position effects have not yet been studied as a single phenomenon. 展开更多
关键词 junk DNA TRANSPOSONS C-VALUE PARADOX gene regulation BALANCE
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Junk the Messages
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作者 DING WENLEI 《Beijing Review》 2008年第16期34-35,共2页
Mobile phone subscribers are fed up with junk mails and are calling for measures to ban it
关键词 PHONE junk the Messages SMS
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Rich on Junk
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作者 LIU XINLIAN 《Beijing Review》 2009年第39期23-23,共1页
A poor boy grew into a billionaire through years of hard work The signs of business acumen had already appeared in Chen Guangbiao as early as 1978, when he was just a 10-year-old being raised in a poor farming family.
关键词 Rich on junk
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本港船·本港行·南海“互市”
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作者 徐素琴 《海洋史研究》 2023年第2期37-46,共10页
清代中国与东南亚的进出口贸易,可分为来船和去船。来船由传统南海贸易国家如暹罗、安南、苏禄等所发,贸易形式分为朝贡贸易和通商贸易,也有西方国家在南海的殖民地如巴达维亚、马尼拉等所发。去船指中国帆船,其航迹遍及南海各国、各地区。
关键词 进出口贸易 巴达维亚 朝贡贸易 南海贸易 中国帆船 暹罗 通商贸易 中国与东南亚
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改进的基于底层虚拟机混淆器的指令混淆框架
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作者 王雅仪 刘琛 +1 位作者 黄天波 文伟平 《计算机应用》 CSCD 北大核心 2023年第2期490-498,共9页
针对底层虚拟机混淆器(OLLVM)在指令混淆层面只支持指令替换一种算法,且仅支持5种运算符和13种替换方案的问题,设计了一种改进版的指令混淆框架InsObf,以加强OLLVM指令层面的混淆效果。InsObf包含指令加花和指令替换,其中指令加花首先... 针对底层虚拟机混淆器(OLLVM)在指令混淆层面只支持指令替换一种算法,且仅支持5种运算符和13种替换方案的问题,设计了一种改进版的指令混淆框架InsObf,以加强OLLVM指令层面的混淆效果。InsObf包含指令加花和指令替换,其中指令加花首先对基本块的指令进行依赖分析,然后插入叠加跳转和虚假循环两种花指令;指令替换在OLLVM的基础上,拓展至13种运算符,共计52种指令替换方案。在底层虚拟机(LLVM)上实现了框架原型后,通过实验表明,与OLLVM相比,InsObf在时间开销增长约10个百分点,空间开销增长约20个百分点的情况下,圈复杂度和抗逆向能力均可提高近4倍;与同样基于OLLVM改进的Armariris和Hikari相比,InsObf在同一量级的时空开销下,可以提供更高的代码复杂度。因此,InsObf可提供指令层级的有效保护。 展开更多
关键词 软件保护 代码混淆 指令混淆 底层虚拟机混淆器 指令加花 指令替换
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道光六年漕粮海运商船所用航海时间的初步研究
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作者 郑海涛 《海交史研究》 2023年第2期75-93,共19页
道光初年,在海运与漕运的争论中,海运支持者对商船航海所用时间的讨论,虽是一个很好的观察当时政治争论的切入点,但此次讨论造成商船出吴淞口到天津所用时间的记载模糊不清。然通过对北洋航线地理环境、时令风信、停泊补给等诸因素的分... 道光初年,在海运与漕运的争论中,海运支持者对商船航海所用时间的讨论,虽是一个很好的观察当时政治争论的切入点,但此次讨论造成商船出吴淞口到天津所用时间的记载模糊不清。然通过对北洋航线地理环境、时令风信、停泊补给等诸因素的分析及商船具体进出口日期提供的佐证,可以清晰地梳理出商船出吴淞口泛海抵津的用时问题。同时,在复原商船航海用时的基础上,指出商船航海所用时间短,对促进中国南北商品贸易的发展有重要影响。 展开更多
关键词 北洋 漕粮 海运 沙船 航海用时
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