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Molecular characterization of Apple necrotic mosaic virus identified in crabapple(Malus spp.) tree of China 预览
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作者 HU Guo-jun DONG Ya-feng +2 位作者 ZHANG Zun-ping FAN Xu-dong REN Fang 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第3期698-701,共4页
Apple necrotic mosaic virus(ApNMV) was identified in crabapple trees with mosaic symptoms from Zaozhuang, Shandong Province, China, by reverse transcription polymerase chain reaction(RT-PCR) analysis. The complete nuc... Apple necrotic mosaic virus(ApNMV) was identified in crabapple trees with mosaic symptoms from Zaozhuang, Shandong Province, China, by reverse transcription polymerase chain reaction(RT-PCR) analysis. The complete nucleotide sequences of one isolate from crabapple(ApNMV-Hai) and two isolates from apple(ApNMV-Hua and-Qu) were determined. The sizes of genomic RNA1, 2 and 3 of the three isolates differed from those of the previously reported isolate ApNMV-P126 from Japanese apple, especially RNA3. Compared with the nucleotide(nt) sequence of RNA3 in isolate P126, those in the Hai and Qu isolates were 7 and 33 nt shorter, respectively, and that of isolate Hua was 7 nt longer. Alignment analyses showed that these differences in size were mainly due to differences in the lengths of the 5′ untranslated region(UTR) and the UTR region between the ORFs encoding the movement protein and the coat protein. In the phylogenetic trees constructed using the full genomic sequences of RNA1, 2 and 3, the isolate Hai clustered into a group with the isolate Qu in the RNA1 tree, but formed an individual branch in the RNA2 and 3 trees. Three recombination events were identified in the nucleotide sequences of RNA1 and 2 among the isolates ApNMV-Hai,-Hua, and-Qu. This is the first report of the full genome sequence of ApNMV in crabapple. 展开更多
关键词 CRABAPPLE MOSAIC SYMPTOM APPLE NECROTIC MOSAIC virus molecular characterization
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Rapid and sensitive detection of cucumber mosaic virus by reverse transcription loop-mediated isothermal amplification
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作者 Xiaorui Fan Yanan Du +9 位作者 Youming Cai Yongchun Zhang Xiao Zhao Jieling Liang Dan Yang Qi Zhang Xiaoxia Zhang Wanjing Zhang Yan Xu Kai Zhao 《生物化学与生物物理学报:英文版》 SCIE CAS CSCD 2019年第2期223-226,共4页
Cucumber mosaic virus(CMV),as a member of Cucumovirus genus,is one of the most common lily viruses and has been reported in many countries [1,2].The CMV-infected plants may show developmental abnormalities of leaves,f... Cucumber mosaic virus(CMV),as a member of Cucumovirus genus,is one of the most common lily viruses and has been reported in many countries [1,2].The CMV-infected plants may show developmental abnormalities of leaves,flowers,and bulbs [1].The symptoms will be extremely severe in plants infected by lily symptomless virus(LSV)[1].So far,CMV has posed a threat to cultivars of lily production.Consequently,it is important to develop an efficient approach to achieve rapid and sensitive detection of CMV.Many visual and serological methods have been reported to detect CMV,such as double antibody sandwich enzyme-linked immunosorbent assay [1],immunosorbent electron microscopy [1],enzyme-linked immunosorbent assay(ELISA)and reverse transcriptase-polymerase chain reaction(RT-PCR)[2].However,these methods are time-consuming and require skilled operator and specialized equipment.Loop-mediated isothermal amplification(LAMP)method provides a possible solution for these problems [3].LAMP was developed by Notomi et al.[4] with high specificity and sensitivity because of Bst DNA polymerase.LAMP method not only is suitable for field and large-scale detection of animal virus with more cost-effective but also could be applied to detect foodborne bacterial pathogens and other viruses with high performances [5].For a naked-eye inspection,SYBR Green I was added to the LAMP reaction products to visualize the results.In this study,we developed a rapid and sensitive LAMP method to detect CMV in lily plants and a simple reverse transcription loop-mediated isothermal amplification(RT-LAMP)to detect field CMV samples in lily bulbs. 展开更多
关键词 CUCUMBER MOSAIC VIRUS TRANSCRIPTION loop-mediated ISOTHERMAL AMPLIFICATION CUCUMBER MOSAIC virus(CMV)
Effects of Early Infection of Tobacco Mosaic Virus on Photosynthetic Proteins and Its Control 预览
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作者 Xiaojing XU Kunfeng SONG +3 位作者 Fengsheng HAO Jiajia ZHAO Hongxiang GUO Weiqun LIU 《农业生物技术:英文版》 CAS 2019年第2期5-9,共5页
[Objectives] This study was conducted to explore the optimal period of TMV control and the physiological sites that interfere with TMV infection.[Methods] Proteome analysis was performed on the host tissues (tobacco p... [Objectives] This study was conducted to explore the optimal period of TMV control and the physiological sites that interfere with TMV infection.[Methods] Proteome analysis was performed on the host tissues (tobacco plants) at different time periods of viral infection, to verify the changes in the expression of differential protein genes and N and PR1-a in the photosynthetic pathway and porphyrin metabolism and chlorophyll metabolism pathways in proteome;and the tobacco plants were treated with different preparations.[Results] The expression levels of N and PR1-a in the tobacco leaves treated with preparation B reached the highest level, and the effects on the expression levels of the differential protein genes were also the most significant. The control effects of the preparations were tested by the half-leaf method, and the results showed that preparation B had a significant control effect against the early infection of the virus.[Conclusions] This study lays a foundation for the prevention and control of tobacco mosaic virus on crops. 展开更多
关键词 TOBACCO MOSAIC virus PROTEOME PHOTOSYNTHETIC system CONTROL effect
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长三角地区农业与自然植被镶嵌体的变化对近地面气象场的影响评估 预览
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作者 梁永晓 马红云 +2 位作者 江志红 保云涛 李海俊 《气象科学》 北大核心 2019年第1期23-33,共11页
利用一个中尺度数值模式WRF3.8/Noah/UCM,对长三角地区近30 a来灌溉水田显著减少,农业与自然植被镶嵌体(以下简称镶嵌体)显著增加这一现象引起的气候效应进行了5 a(2008-2012年)高分辨数值模拟。试验采用了ChinaLC土地覆盖资料,利用MODI... 利用一个中尺度数值模式WRF3.8/Noah/UCM,对长三角地区近30 a来灌溉水田显著减少,农业与自然植被镶嵌体(以下简称镶嵌体)显著增加这一现象引起的气候效应进行了5 a(2008-2012年)高分辨数值模拟。试验采用了ChinaLC土地覆盖资料,利用MODIS反照率和叶面积指数产品分别验证了ChinaLC在镶嵌体和水田之间的分类可靠性。根据研究区内台站观测资料评估了ChinaLC和WRF模式自带的USGS资料模拟结果,进一步证明土地覆盖资料ChinaLC的分类准确性,有助于提高模式的模拟性能。通过对长三角地区镶嵌体面积变化的对比试验进行分析,结果表明:区域内由灌溉水田转变为镶嵌体后,不仅会使非城市区气象条件改变,同时也会影响临近的城市区,由于非城市区增温幅度大于城市区,会导致城郊温差减弱;镶嵌体增加导致江苏西南部、浙江北部气温上升0.1~0.3℃,风速减弱0.1~0.3 m·s-1,比湿降低0.05~0.15 g·kg-1,边界层高度上升40 m。在镶嵌体显著增加的南京北部-滁州以及江苏西南部一带降水减少,南京北部-滁州地区月平均降水减少了0.6 mm·d-1,马鞍山-溧水降水减少了0.2 mm·d-1。 展开更多
关键词 ChinaLC 土地覆盖 镶嵌体 数值模拟
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拼镶圆盘换能器参数仿真研究 预览
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作者 张小川 孙芹东 王超 《舰船电子工程》 2019年第2期85-87,共3页
拼镶弯曲圆盘换能器的建模仿真是对换能器声场物理过程的认知,通过仿真研究原理,优化设计参数可以有效提高换能器的工作效率。为了获得拼镶弯曲圆盘换能器的最优参数,利用有限元软件Ansys建立其有限元模型,在其金属结构不变的情况下对... 拼镶弯曲圆盘换能器的建模仿真是对换能器声场物理过程的认知,通过仿真研究原理,优化设计参数可以有效提高换能器的工作效率。为了获得拼镶弯曲圆盘换能器的最优参数,利用有限元软件Ansys建立其有限元模型,在其金属结构不变的情况下对拼镶压电陶瓷环的不同参数进行了仿真,进而分析了参数对谐振频率、谐波响应、发送电压响应的影响,确定各参数对换能器性能的影响,寻找换能器设计的最优参数。 展开更多
关键词 拼镶 换能器 压电陶瓷 参数仿真
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笔触风格化技术研究综述 预览
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作者 方建文 黄钢 曹文明 《计算机工程与应用》 CSCD 北大核心 2019年第9期33-37,86共6页
笔触风格化技术是图像艺术风格化最为经典和重要的研究方向,产生了众多的研究成果,也引起了越来越多研究人员的兴趣。总结了基于笔触图像风格化技术的研究现状,分析了笔触风格化系统的基本构成和各种不同类型算法的特点,指出了目前笔触... 笔触风格化技术是图像艺术风格化最为经典和重要的研究方向,产生了众多的研究成果,也引起了越来越多研究人员的兴趣。总结了基于笔触图像风格化技术的研究现状,分析了笔触风格化系统的基本构成和各种不同类型算法的特点,指出了目前笔触风格化方法的缺点,揭示了图像风格化技术的发展趋势,为进一步研究和探索图像风格化提供了方向。 展开更多
关键词 非真实感绘制 图像风格化 笔触 全局优化 马赛克
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菊花上番茄斑萎病毒的血清学检测及分子鉴定
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作者 郭京泽 胡佳续 +3 位作者 王仲敏 刘梅 李兴红 王万骞 《植物保护学报》 CAS CSCD 北大核心 2019年第1期253-254,共2页
菊花是一种重要的花卉和药用植物,受到病害侵染时,其会失去观赏价值。目前我国报道的侵染菊花的病毒种类主要有菊花B病毒(Chrysanthemum virus B,CVB)、番茄不孕病毒(Tomato aspermy virus,TAV)、烟草花叶病毒(Tobacco mosaic virus,TMV... 菊花是一种重要的花卉和药用植物,受到病害侵染时,其会失去观赏价值。目前我国报道的侵染菊花的病毒种类主要有菊花B病毒(Chrysanthemum virus B,CVB)、番茄不孕病毒(Tomato aspermy virus,TAV)、烟草花叶病毒(Tobacco mosaic virus,TMV)、黄瓜花叶病毒(Cucumber mosaic virus,CMV)等。 展开更多
关键词 番茄斑萎病毒 血清学检测 菊花 分子鉴定 MOSAIC 番茄不孕病毒 烟草花叶病毒 黄瓜花叶病毒
Discernible image mosaic with edge-aware adaptive tiles
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作者 Pengfei Xu Jianqiang Ding +1 位作者 Hao Zhang Hui Huang 《计算可视媒体(英文版)》 CSCD 2019年第1期45-58,共14页
We present a novel method to produce discernible image mosaics, with relatively large image tiles replaced by images drawn from a database, to resemble a target image. Compared to existing works on image mosaics, the ... We present a novel method to produce discernible image mosaics, with relatively large image tiles replaced by images drawn from a database, to resemble a target image. Compared to existing works on image mosaics, the novelty of our method is two-fold.Firstly, believing that the presence of visual edges in the final image mosaic strongly supports image perception,we develop an edge-aware photo retrieval scheme which emphasizes the preservation of visual edges in the target image. Secondly, unlike most previous works which apply a pre-determined partition to an input image, our image mosaics are composed of adaptive tiles, whose sizes are determined based on the available images in the database and the objective of maximizing resemblance to the target image. We show discernible image mosaics obtained by our method, using image collections of only moderate size. To evaluate our method, we conducted a user study to validate that the image mosaics generated present both globally and locally appropriate visual impressions to the human observers. Visual comparisons with existing techniques demonstrate the superiority of our method in terms of mosaic quality and perceptibility. 展开更多
关键词 IMAGE MOSAIC IMAGE RETRIEVAL IMAGE SYNTHESIS
Comparative transcriptome analysis reveals differential gene expression in resistant and susceptible tobacco cultivars in response to infection by cucumber mosaic virus 预览
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作者 Dan Liu Yazeng Cheng +6 位作者 Min Gong Qiang Zhao Caihong Jiang Lirui Cheng Min Ren Yuanying Wang Aiguo Yang 《作物学报:英文版》 CAS CSCD 2019年第3期307-321,共15页
Cucumber mosaic virus(CMV) is one of the most severe viral diseases transmitted by aphids infecting Solanum crops in China, causing great losses of crop yields and income in rural communities.The tobacco cultivars NC8... Cucumber mosaic virus(CMV) is one of the most severe viral diseases transmitted by aphids infecting Solanum crops in China, causing great losses of crop yields and income in rural communities.The tobacco cultivars NC82 and Taiyan 8 are closely related but differ in resistance to CMV.NC82 is susceptible to infection and Taiyan 8 is resistant, but the mechanisms underlying this difference in resistance are not clear.In this study, we conducted RNA sequencing to analyze changes in gene expression induced in the leaves of Taiyan 8 and NC82 upon systemic infection with CMV, compared with gene expression in the leaves of mock-inoculated plants.Leaves were sampled at one, three, eight, and 15 days after infection.In total, 3443 and 747 differentially expressed genes were identified in Taiyan 8 and NC82, respectively.Gene ontology and pathway enrichment analyses revealed that the different responses to CMV infection between cultivars were based on microtubulebased processes, pentose and glucuronate interconversions, plant–pathogen interaction,and hormone signal transduction pathways.Genes encoding pathogenesis-related proteins, disease-resistance proteins, lipoxygenase, cellulose synthase, an auxin response factor, and an ethylene receptor showed different expression patterns.The differences in gene expression following CMV infection likely contributed to the different resistance levels of these two tobacco cultivars.The comprehensive transcriptome dataset described here,which includes candidate response genes, will serve as a resource for further studies of the molecular mechanisms associated with tobacco defense responses against CMV. 展开更多
关键词 CUCUMBER MOSAIC virus TOBACCO Resistance TRANSCRIPTOME Differential gene expression
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Chinese wheat mosaic virus:A long-term threat to wheat in China 预览
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作者 GUO Liu-ming HE Jing +2 位作者 LI Jing CHEN Jian-ping ZHANG Heng-mu 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第4期821-829,共9页
In China,a soil-borne virus causing a disease of winter wheat and associated with Polymyxa graminis,has been reported for many years and is now recognized as a new species,Chinese wheat mosaic virus(CWMV).Since the de... In China,a soil-borne virus causing a disease of winter wheat and associated with Polymyxa graminis,has been reported for many years and is now recognized as a new species,Chinese wheat mosaic virus(CWMV).Since the determination of its genomic sequence,more progress has been made in understanding its genomic structure and functions.Molecular and serological methods have been developed to help survey the distribution of the virus and to provide the basic information needed for disease forecasting and control.At present,the best countermeasure is cultivation of resistant wheat varieties.In addition,development and application of some auxiliary countermeasures,such as rotation of non-host crops,delayed seed-sowing,reasonable application of nitrogen fertilizer,and treatment of imported seeds with fungicides before sowing,may be helpful for controlling the disease.The viral distribution and damage,virion properties,genome organization and spontaneous mutation,temperature sensitivity,and disease management options are here reviewed and/or discussed to help in developing more cost-effective countermeasures to control the disease in the future. 展开更多
关键词 CHINESE WHEAT MOSAIC virus(CWMV) Polymyxa graminis disease control GENOME structure SPONTANEOUS mutation temperature sensitivity
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Plant infection by two different viruses induce contrasting changes of vectors fitness and behavior
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作者 Quentin Chesnais Aude Couty +2 位作者 Maryline Uzest Veronique Brault Arnaud Ameline 《昆虫科学:英文版》 SCIE CAS CSCD 2019年第1期86-96,共11页
Insect-vectored plant viruses can induce changes in plant phenotypes,thus influencing plant-vector interactions in a way that may promote their dispersal according to their mode of transmission (i.e.,circulative vs.no... Insect-vectored plant viruses can induce changes in plant phenotypes,thus influencing plant-vector interactions in a way that may promote their dispersal according to their mode of transmission (i.e.,circulative vs.noncirculative).This indirect vector manipulation requires host-virus-vector coevolution and would thus be effective solely in very specific plant-virus-vector species associations.Some studies suggest this manipulation may depend on multiple factors relative to various intrinsic characteristics of vectors such as transmission efficiency.In anintegrative study,we tested the effects of infection of the Brassicaceae Camelina sativa with the noncirculative Cauliflower mosaic virus (CaMV)or the circulative Turnip yellows virus (TuYV)on the host-plant colonization of two aphid species differing in their virus transmission efficiency:the polyphagous Myzus persicae,efficient vector of both viruses,and the Brassicaceae specialist Brevicoryne brassicae,poor vector of TuYV and efficient vector of CaMV.Results confirmed the important role of virus mode of transmission as plant-mediated effects of CaMV on the two aphid species induced negative alterations of feeding behavior (i.e.,decreased phloem sap ingestion)and performance that were both conducive for virus fitness by promoting dispersion after a rapid acquisition.In addition,virus transmission efficiency may also play a role in vector manipulation by viruses as only the responses of the efficient vector to plant-mediated effects of TuYV,that is,enhanced feeding behavior and performances,were favorable to their acquisition and further dispersal.Altogether,this work demonstrated that vector transmission efficiency also has to be considered when studying the mechanisms underlying vector manipulation by viruses.Our results also re- inforce the idea that vector manipulation requires coevolution between plant,virus and vector. 展开更多
关键词 APHID vector CAULIFLOWER mosaic VIRUS electrical penetration graph host-plant selection life history traits TURNIP YELLOWS VIRUS
基于图元紧密型分布合成的镶嵌画效果模拟
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作者 陈婕 杨刚 杨猛 《系统仿真学报》 CSCD 北大核心 2018年第2期473-481,共9页
提出一种方法,能快速合成多种形状图元的紧密型分布,从而实现镶嵌画效果模拟。该方法基于Voronoi图进行区域分割,每一个分割小块代表一个图元所占空间,从而实现图元紧密分布。在生成Voronoi图的过程中,使用不同的距离度量标准控制Vorono... 提出一种方法,能快速合成多种形状图元的紧密型分布,从而实现镶嵌画效果模拟。该方法基于Voronoi图进行区域分割,每一个分割小块代表一个图元所占空间,从而实现图元紧密分布。在生成Voronoi图的过程中,使用不同的距离度量标准控制Voronoi多边形形状,从而实现五种不同形状图元的紧密型分布。进一步地,该方法可通过生成具有尺度、方向变化的图元分布,模拟富有变化的镶嵌画效果。此外,还借助GPU的计算能力对Voronoi图生成过程进行了加速。实验结果表明,该方法合成效果好,合成效率可达交互。 展开更多
关键词 图元 镶嵌画 紧密型分布 VORONOI图 纹理合成 向量场
马赛克设备改纺花式纱生产实践 预览
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作者 朱丽平 刘晓燕 《纺织器材》 2018年第2期40-42,共3页
为了增加纺纱品种,在FA506型细纱机技改集聚赛络纺基础上,加装品特开普竹节纺纱系统,研究马赛克设备车头部位、牵伸部位和相关纺织器材专件选配;结合集聚赛络纺纱技术,进行普通、竹节或段彩效果的花式纱和马赛克渐变花式纱纺制实... 为了增加纺纱品种,在FA506型细纱机技改集聚赛络纺基础上,加装品特开普竹节纺纱系统,研究马赛克设备车头部位、牵伸部位和相关纺织器材专件选配;结合集聚赛络纺纱技术,进行普通、竹节或段彩效果的花式纱和马赛克渐变花式纱纺制实践,并总结异常情况处理方法。指出:加装品特开普竹节纺纱系统,可纺多种花式纱,且纤维不会被打断,可满足客户个性化定制和追求独特的创新需求。 展开更多
关键词 马赛克 花式纱 品特开普竹节纺纱 牵伸 纺织器材
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基于Python的人脸马赛克处理软件 预览
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作者 张瀚匀 孙容海 +1 位作者 于梦竹 黄丽艳 《信息技术》 2018年第8期52-54,共3页
为了保护图像中的人脸信息,文中设计和开发出了一个人脸马赛克处理软件。该软件基于Python+OpenCV3的模式,在PyCharm2016的环境下开发,通过Python标准的Tk GUI工具包的接口实现了为单幅图像人脸马赛克处理和多幅图像人脸马赛克处理的功... 为了保护图像中的人脸信息,文中设计和开发出了一个人脸马赛克处理软件。该软件基于Python+OpenCV3的模式,在PyCharm2016的环境下开发,通过Python标准的Tk GUI工具包的接口实现了为单幅图像人脸马赛克处理和多幅图像人脸马赛克处理的功能,可有效保护人脸信息。 展开更多
关键词 人脸图像 马赛克 PYTHON OpenCV3
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《极地、冰区船舶》
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作者 《船舶工程》编辑部 《船舶工程》 CSCD 北大核心 2018年第8期J0007-J0013,共7页
2018年6月19日-23日在瑞士达沃斯召开了一场国际盛会——《极地2018》科学会议。在这场盛会中,我国再次“高调”地展示了自身在极地研究方面的实力。国家自然资源部的陈大可院士做了题为《中国对SOOS和MOSAIC国际计划的潜在贡献》的大... 2018年6月19日-23日在瑞士达沃斯召开了一场国际盛会——《极地2018》科学会议。在这场盛会中,我国再次“高调”地展示了自身在极地研究方面的实力。国家自然资源部的陈大可院士做了题为《中国对SOOS和MOSAIC国际计划的潜在贡献》的大会特邀报告,代表中国系统地介绍了中国未来几年的极地考察计划对极地国际科考计划的贡献,并播放了即将投入使用的我国“雪龙2”号极地科考破冰船短视频,给与会代表留下了深刻印象。现有的南北极国际大型计划中已有明显的中国要素体现,如SOOS计划中的中国“大环”计划、MOSCAiC计划中5套综合浮标站中方提供了2套由国家重点研发专项支持、集成研发的无人冰站系统,加上即将于2019年进行极地试航的“雪龙2”号极地科考破冰船,中国己完全有能力为国际极地海洋乃至整个极地的科学研究做出更大的贡献,而国际极地科考舞台上也将留下更多中国的印记和声音。 展开更多
关键词 极地考察 冰区 国际计划 船舶 MOSAIC 自然资源部 特邀报告 科学研究
基于DEM的SPOT5遥感数据配准与镶嵌 预览 被引量:1
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作者 白潍铭 赵帅 姚畅 《资源环境与工程》 2018年第3期462-466,共5页
由于SPOT5相邻两幅遥感影像重叠区域较少,尤其是在地形起伏较大的南半球地区,受地球自转影响较大,在两幅影像做配准与镶嵌时出现较大的几何误差,无法满足影像的处理与使用。通过基于自带地理坐标的两幅SPOT5影像直接镶嵌、基于配准后的... 由于SPOT5相邻两幅遥感影像重叠区域较少,尤其是在地形起伏较大的南半球地区,受地球自转影响较大,在两幅影像做配准与镶嵌时出现较大的几何误差,无法满足影像的处理与使用。通过基于自带地理坐标的两幅SPOT5影像直接镶嵌、基于配准后的影像镶嵌及基于DEM正射校正与配准相结合的影像镶嵌,探讨三种方式的镶嵌效果,并对镶嵌结果作精度评价。研究表明,利用DEM数据进行正射校正后再配准的镶嵌方法精度最高,基于配准后的影像镶嵌次之,基于地理坐标的镶嵌效果最差。因而在做两幅SPOT5影像数据镶嵌前体现出基于DEM正射校正的必要性,同时能够满足后续的各项影像处理与使用需求,也为以后在同类地区使用SPOT5进行数据处理提供借鉴。 展开更多
关键词 DEM SPOT5 配准 镶嵌 南半球
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高分辨率遥感影像纠正、拼接系统的研究 预览
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作者 付海龙 安园园 曲超 《科技创新与应用》 2018年第14期81-82,共2页
随着IKONOS、 QuickBird、 SPOT等一批高分辨率卫星影像的推出,高分辨率遥感卫星迅速发展,遥感影像用于测绘将是今 后发展的趋势.文章着重研究了遥感影像的纠正、拼接系统.文章的主要讨论内容如下:基于有理函数的通用传感器模型、纠正... 随着IKONOS、 QuickBird、 SPOT等一批高分辨率卫星影像的推出,高分辨率遥感卫星迅速发展,遥感影像用于测绘将是今 后发展的趋势.文章着重研究了遥感影像的纠正、拼接系统.文章的主要讨论内容如下:基于有理函数的通用传感器模型、纠正后的遥 感影像镶嵌的基本原理、影像纠正拼接系统的架构设计方案以及示例程序效果图. 展开更多
关键词 传感器模型 纠正 镶嵌
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20例嵌合型Turner综合征的辅助生殖助孕及相关文献复习 预览
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作者 许咏乐 孟庆霞 +5 位作者 邹琴燕 杨慎敏 偶健 张芹 王玮 李红 《生殖医学杂志》 CAS 2018年第11期1120-1125,共6页
目的 探讨嵌合型Turner综合征患者的生育功能及辅助生殖助孕的方式。方法 选择2011年4月至2017年10月于苏州市立医院生殖中心收治的20例因不孕症要求行辅助生殖助孕的嵌合型Turner综合征患者,回顾性分析临床资料、辅助生殖助孕治疗过程... 目的 探讨嵌合型Turner综合征患者的生育功能及辅助生殖助孕的方式。方法 选择2011年4月至2017年10月于苏州市立医院生殖中心收治的20例因不孕症要求行辅助生殖助孕的嵌合型Turner综合征患者,回顾性分析临床资料、辅助生殖助孕治疗过程、妊娠结局及其子代核型。结果 20例患者经过辅助生殖助孕,15例分娩正常核型子代(其中14例行IVF/ICSI,1例行PGS),1例孕早期稽留流产(绒毛染色体核型为47,XY,+13),1例生化妊娠,3例未孕(其中包括1例赠卵IVF)。结论 对于卵巢功能尚未衰竭的嵌合型Turner综合征患者,结合临床具体情况,可尊重患者意愿尝试自体卵母细胞的辅助生殖助孕,治疗前需知情同意、充分评估。 展开更多
关键词 TURNER综合征 嵌合体 辅助生殖 体外受精-胚胎移植
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Characterization of a Watermelon mosaic virus Isolate Inducing a Severe Disease in Watermelon in Saudi Arabia 预览
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作者 Adyatma Irawan Santosa Ibrahim Mohamed Al-Shahwan +2 位作者 Omer Ahmed Abdalla Mohamed Ali Al-Saleh Mahmoud Ahmed Amer 《农业科学与技术:A》 2018年第4期220-229,共10页
In one of the field visits to cucurbits-growing areas in vicinity of Riyadh city during 2013-2015,severe virus disease-like symptoms were observed on watermelon in Al-Ammariyah area.Mechanical inoculation of the diffe... In one of the field visits to cucurbits-growing areas in vicinity of Riyadh city during 2013-2015,severe virus disease-like symptoms were observed on watermelon in Al-Ammariyah area.Mechanical inoculation of the different plant species used in the host range study,from the collected symptomatic watermelon samples,produced mosaic symptoms on Citrullus lanatus,Cucumis sativus,Cucurbita pepo,C.melo,C.melo subsp.melo and Nicotiana benthamiana,but chlorotic local lesions on Chenopodium amaranticolor.No symptoms were observed on the rest of the other inoculated plant species.The virus was transmitted by Aphis gossypii and A.craccivora in a non-persistent manner.Transmission electron microscopic examination of watermelon samples using the leaf dip method revealed only microscopic filamentous shaped virus particles measuring 750 nm in length and 12 nm in diameter in average.ELISA revealed positive results only to Watermelon mosaic virus(WMV)and negative to Zucchini yellow mosaic virus(ZYMV),Papaya ringspot virus(PRSV),Cucumber mosaic virus(CMV)and Squash mosaic virus(SqMV).Specific bands of approximately 825 bp were formed on agarose gel following electrophoresis of the reverse transcriptase-polymerase chain reaction(RT-PCR)products of each of the naturally infected C.lanatus,and artificially infected C.lanatus,C.pepo,C.sativus,and N.benthamiana.The homology tree that was constructed from multiple sequence alignments of the detected Saudi Arabian isolate of WMV(WMV-SA)with 18 other isolates of WMV from nine different countries indicated close relationships between them.Two isolates from Spain and two other isolates from Iran were more closely related to the WMV-SA whereas the isolate from Poland was the least. 展开更多
关键词 WATERMELON ELISA NUCLEOTIDE sequence RT-PCR SAUDI ARABIA WATERMELON MOSAIC virus
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Call me MOSAIC——单维空间的多维转变之旅
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作者 李梦奇 郭振江(摄影) 《设计新潮》 2018年第2期98-101,共4页
“假设一个普通人的阅读生涯可以持续60年,每一年阅读数量达到20本,他一辈子也只能读到1200本书,这个数字里还不算上重读的部分。我们想做的这种书店,就是为了真实解决这部分人的需求而存在。”书店老板的目标坚决而笃定,建筑师以... “假设一个普通人的阅读生涯可以持续60年,每一年阅读数量达到20本,他一辈子也只能读到1200本书,这个数字里还不算上重读的部分。我们想做的这种书店,就是为了真实解决这部分人的需求而存在。”书店老板的目标坚决而笃定,建筑师以此为基础进行设计。在经历过无数个掀翻屋顶的“头脑风暴”之后,在数不清的日夜加班之后,CalImeMOSAIC终于露出了真面容。 展开更多
关键词 MOSAIC 多维 空间 建筑师 书店 基础 屋顶
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