To explore an effective and reliable karyotyping method in Brassica crop plants,Cot-1 DNA was isolated from Brassica oleracea genome,labeled as probe with Biotin-Nick Translation Mix kit,in situ hybridized to mitotic ...To explore an effective and reliable karyotyping method in Brassica crop plants,Cot-1 DNA was isolated from Brassica oleracea genome,labeled as probe with Biotin-Nick Translation Mix kit,in situ hybridized to mitotic spreads,and where specific fluorescent bands showed on each chromosome pair.25S and 5S rDNA were labeled as probes with DIG-Nick Translation Mix kit and Biotin-Nick Translation Mix kit,respectively,in situ hybridized to mitotic preparations,where 25S rDNA could be detected on two chromosome pairs and 5S rDNA on only one.Cot-1 DNA contains rDNA and chromosome sites identity between Cot-1 DNA and 25S rDNA was determined by dual-colour fluores-cence in situ hybridization.All these showed that the karyo-typing technique based on a combination of rDNA and Cot-1 DNA chromosome landmarks is superior to all but one.A more exact karyotype of B.oleracea has been analyzed based on a combination of rDNA sites,Cot-1 DNA fluorescent bands,chromosome lengths and arm ratios.展开更多
Fluorescence in situ hybridization （FISH） and comparative genomic hybridization （CGH） were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of Cot-1...Fluorescence in situ hybridization （FISH） and comparative genomic hybridization （CGH） were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of Cot-1 DNA and genomic DNA＇from the cultivated rice. The coverage percentage （%） and size （Mb） of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana were 47.1 ±0.16, 38.61 ±0.13, 44.38＋_0.13, and 212.33 ± 1.21,269.42 ± 0.89, 532.56± 1.68 Mb, respectively. The coverage percentage and size of genomic DNA from O. sativa in O. officinalis and O. meyeriana were 91.0, 93.6% and 634, 1 123 Mb, respectively, in which 365 and 591 Mb in O. officinalis and O. meyeriana were from O. sativa genomic DNA, but not from repetitive sequences of O. sativa, and the uncoverage genome size in O. officinalis and O. meyeriana were 64 and 78 Mb, respectively. In addition, karyotype analysis was conducted based on the signal bands of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana. The results showed that highly and moderately repetitive sequences in Oryza genus were conserved as the functional genes during evolution. The repetitive sequences reduplication may be one of the important causes of the genome enlargement of O. officinalis and O. meyeriana, and O. officinalis genome enlarged more slowly when compared with O. meyeriana. Based on the above results, it is concluded that O. officinalis and O. meyeriana were formed by reduplication, rearrangement, and gene selective loss during the evolution process.展开更多
为了提高侵蚀沟立体建模与监测的精度,该文采用消费级无人机作为低空遥感平台,以黄土高原一典型切沟为研究对象,通过无人机采集的倾斜影像与部署的地面控制点,采用多视立体运动恢复结构方法(structure from motion with multi-view ster...为了提高侵蚀沟立体建模与监测的精度,该文采用消费级无人机作为低空遥感平台,以黄土高原一典型切沟为研究对象,通过无人机采集的倾斜影像与部署的地面控制点,采用多视立体运动恢复结构方法(structure from motion with multi-view stereo,Sf M-MVS)构建了高精度侵蚀沟表面模型,对其建模精度与数字高程模型、正射影像等成果进行分析,并与传统正射航图建模成果进行了比较。结果表明:构建的侵蚀沟稠密点云模型的水平均方根误差约为0.096 m,高程均方根误差约为0.018 m,满足1:500比例尺数字线划图与正射影像图的要求。与正射航图建模成果相比,高程误差减小了50%;侵蚀沟稠密点云的整体密度与地面激光雷达相当,且避免了后者多站拼接造成的密度不均问题。除了沟头部分的小块内凹区域,沟壁、沟头部分没有明显的空洞,植被覆盖的区域也能够正常建模。而正射航图的建模成果中在沟头内凹部分以及植被覆盖部分存在大块的空洞;由侵蚀沟的数字高程模型与等高线图可见,构建的侵蚀沟模型能够准确地反映切沟的形态特征。总体而言,该方法在侵蚀沟的高精度建模与监测方面具有显著优势,具有推广应用的潜力。展开更多
Fluorescence in situ hybridization (FISH)was applied to somatic chromosomes preparations of Oryza officinalis Wall. (CC), O. sativa L. (AA)×O. offi-cinalis F1 hybrid (AC), backcross progenies BC1 (AAC and ACC), O...Fluorescence in situ hybridization (FISH)was applied to somatic chromosomes preparations of Oryza officinalis Wall. (CC), O. sativa L. (AA)×O. offi-cinalis F1 hybrid (AC), backcross progenies BC1 (AAC and ACC), O. latifolia Desv. (CCDD), O. alta Swallen (CCDD) and O. punctata Kotschy (BBCC) with a labelled probe of C0t-1 DNA from O. officinalis. In O. officinalis, the homologous chromosomes showed similar signal bands probed by C0t-1 DNA and karyotype analysis was conducted based on the band patterns. Using no blocking DNA, the probe identified the chromosomes of C genome clearly, but detected few signals on chromosomes of A genome in the F1 hybrid and two backcross progenies of BC1. It is obvious that the highly and moderately repetitive DNA sequences were considerably different between C and A genomes. The chromosomes of C genome were also discriminated from the chromosomes of D- and B-genome in the tetraploid species O. latifolia, O. alta and O. punctata by C0t-1 DNA-FISH. Compari-son of the fluorescence intensity on the chromo-somes of B, C and D genomes in O. latifolia, O. alta, and O. punctata indicated that the differentiations between C and D genomes are less than that be-tween C and B genomes. The relationship between C and D genomes in O. alta is closer than that of C and D genomes in O. latifolia. This would be one of thecauses for the fact that both the genomes are of the same karyotype (CCDD) but belong to different spe-cies. The above results showed that the C0t-1 DNA had a high specificity of genome and species. In this paper, the origin of allotetraploid in genus Oryza is also discussed.展开更多
(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics were prepared via the conventional solid-state reaction route with the aim of reducing thetf value and improving the thermal stability.The phase composition and t...(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics were prepared via the conventional solid-state reaction route with the aim of reducing thetf value and improving the thermal stability.The phase composition and the microstructure were investigated using X-ray diffraction,Raman spectra,and scanning electron microscopy.A set of phase transitions which were induced by composition had been confirmed via the sequence:rutile structure→coexistence of rutile and columbite phase→columbite phase.For(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics,the addition of ZnNb2O6 content(x=0–1)led to the decrease ofer from 62.98 to 23.94.As a result of the high Q×?of ZnNb2O6 ceramics,the increase of ZnNb2O6 content also led to the lower sintering temperatures and the higher Q×?values.Thetf value was reduced from+108.04(x=0)to–49.31 ppm/℃(x=1).Among them,high density 0.5CoTiNb2O8-0.5ZnNb2O6 ceramics were obtained at 1175℃with excellent microwave dielectric properties of εr 39.2,Q×? 40013 GHz,and tf+3.57 ppm/℃.展开更多
基金This work was supported by the President Foundation of the Institute of Oil Crops,Chinese Academy of Agricultural Sciences(No.200301)the Topping Youth Foundation of Hubei Province(No.2005ABB028)the Chenguang Program of Wuhan City(No.20045006071-37).
文摘To explore an effective and reliable karyotyping method in Brassica crop plants,Cot-1 DNA was isolated from Brassica oleracea genome,labeled as probe with Biotin-Nick Translation Mix kit,in situ hybridized to mitotic spreads,and where specific fluorescent bands showed on each chromosome pair.25S and 5S rDNA were labeled as probes with DIG-Nick Translation Mix kit and Biotin-Nick Translation Mix kit,respectively,in situ hybridized to mitotic preparations,where 25S rDNA could be detected on two chromosome pairs and 5S rDNA on only one.Cot-1 DNA contains rDNA and chromosome sites identity between Cot-1 DNA and 25S rDNA was determined by dual-colour fluores-cence in situ hybridization.All these showed that the karyo-typing technique based on a combination of rDNA and Cot-1 DNA chromosome landmarks is superior to all but one.A more exact karyotype of B.oleracea has been analyzed based on a combination of rDNA sites,Cot-1 DNA fluorescent bands,chromosome lengths and arm ratios.
基金This work was supported by the National High Tech R ＆ D Program of China （863 Program, 2004AA227120） the Scientific Research Foundation for the Returned 0verseas Chinese Scholars, Ministry of Education of China （BZY04003）+1 种基金 China Postdoctoral Science Foundation （20040350574）the Project of Science and Technology for Youth, Wuhan, China （2004500607135）.
文摘Fluorescence in situ hybridization （FISH） and comparative genomic hybridization （CGH） were applied to somatic chromosomes preparations of Oryza sativa, O. officinalis, and O. meyeriana with labeled probes of Cot-1 DNA and genomic DNA＇from the cultivated rice. The coverage percentage （%） and size （Mb） of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana were 47.1 ±0.16, 38.61 ±0.13, 44.38＋_0.13, and 212.33 ± 1.21,269.42 ± 0.89, 532.56± 1.68 Mb, respectively. The coverage percentage and size of genomic DNA from O. sativa in O. officinalis and O. meyeriana were 91.0, 93.6% and 634, 1 123 Mb, respectively, in which 365 and 591 Mb in O. officinalis and O. meyeriana were from O. sativa genomic DNA, but not from repetitive sequences of O. sativa, and the uncoverage genome size in O. officinalis and O. meyeriana were 64 and 78 Mb, respectively. In addition, karyotype analysis was conducted based on the signal bands of Cot-1 DNA in O. sativa, O. officinalis, and O. meyeriana. The results showed that highly and moderately repetitive sequences in Oryza genus were conserved as the functional genes during evolution. The repetitive sequences reduplication may be one of the important causes of the genome enlargement of O. officinalis and O. meyeriana, and O. officinalis genome enlarged more slowly when compared with O. meyeriana. Based on the above results, it is concluded that O. officinalis and O. meyeriana were formed by reduplication, rearrangement, and gene selective loss during the evolution process.
文摘为了提高侵蚀沟立体建模与监测的精度,该文采用消费级无人机作为低空遥感平台,以黄土高原一典型切沟为研究对象,通过无人机采集的倾斜影像与部署的地面控制点,采用多视立体运动恢复结构方法(structure from motion with multi-view stereo,Sf M-MVS)构建了高精度侵蚀沟表面模型,对其建模精度与数字高程模型、正射影像等成果进行分析,并与传统正射航图建模成果进行了比较。结果表明:构建的侵蚀沟稠密点云模型的水平均方根误差约为0.096 m,高程均方根误差约为0.018 m,满足1:500比例尺数字线划图与正射影像图的要求。与正射航图建模成果相比,高程误差减小了50%;侵蚀沟稠密点云的整体密度与地面激光雷达相当,且避免了后者多站拼接造成的密度不均问题。除了沟头部分的小块内凹区域,沟壁、沟头部分没有明显的空洞,植被覆盖的区域也能够正常建模。而正射航图的建模成果中在沟头内凹部分以及植被覆盖部分存在大块的空洞;由侵蚀沟的数字高程模型与等高线图可见,构建的侵蚀沟模型能够准确地反映切沟的形态特征。总体而言,该方法在侵蚀沟的高精度建模与监测方面具有显著优势,具有推广应用的潜力。
基金supported by the National Program of High Technology Development(Grant No.2004AA227120)the Scientific Research Foundation for the Returned 0verseas Chinese Scholars,State Education Ministry(Grant No.BZY04003)+1 种基金China Postdoctoral Science Foundation(Grant No.20040350574)the Project of Science and Technology for Youth,Wuhan,China(Grant No.2004500607135).
文摘Fluorescence in situ hybridization (FISH)was applied to somatic chromosomes preparations of Oryza officinalis Wall. (CC), O. sativa L. (AA)×O. offi-cinalis F1 hybrid (AC), backcross progenies BC1 (AAC and ACC), O. latifolia Desv. (CCDD), O. alta Swallen (CCDD) and O. punctata Kotschy (BBCC) with a labelled probe of C0t-1 DNA from O. officinalis. In O. officinalis, the homologous chromosomes showed similar signal bands probed by C0t-1 DNA and karyotype analysis was conducted based on the band patterns. Using no blocking DNA, the probe identified the chromosomes of C genome clearly, but detected few signals on chromosomes of A genome in the F1 hybrid and two backcross progenies of BC1. It is obvious that the highly and moderately repetitive DNA sequences were considerably different between C and A genomes. The chromosomes of C genome were also discriminated from the chromosomes of D- and B-genome in the tetraploid species O. latifolia, O. alta and O. punctata by C0t-1 DNA-FISH. Compari-son of the fluorescence intensity on the chromo-somes of B, C and D genomes in O. latifolia, O. alta, and O. punctata indicated that the differentiations between C and D genomes are less than that be-tween C and B genomes. The relationship between C and D genomes in O. alta is closer than that of C and D genomes in O. latifolia. This would be one of thecauses for the fact that both the genomes are of the same karyotype (CCDD) but belong to different spe-cies. The above results showed that the C0t-1 DNA had a high specificity of genome and species. In this paper, the origin of allotetraploid in genus Oryza is also discussed.
基金financially supported by the National Natural Science Foundation of China (No. 51772022)
文摘(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics were prepared via the conventional solid-state reaction route with the aim of reducing thetf value and improving the thermal stability.The phase composition and the microstructure were investigated using X-ray diffraction,Raman spectra,and scanning electron microscopy.A set of phase transitions which were induced by composition had been confirmed via the sequence:rutile structure→coexistence of rutile and columbite phase→columbite phase.For(1-x)CoTiNb2O8-x ZnNb2O6 microwave dielectric ceramics,the addition of ZnNb2O6 content(x=0–1)led to the decrease ofer from 62.98 to 23.94.As a result of the high Q×?of ZnNb2O6 ceramics,the increase of ZnNb2O6 content also led to the lower sintering temperatures and the higher Q×?values.Thetf value was reduced from+108.04(x=0)to–49.31 ppm/℃(x=1).Among them,high density 0.5CoTiNb2O8-0.5ZnNb2O6 ceramics were obtained at 1175℃with excellent microwave dielectric properties of εr 39.2,Q×? 40013 GHz,and tf+3.57 ppm/℃.
