The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene （ZmC4Ppc） is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult fo...The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene （ZmC4Ppc） is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult for marker-assisted selection （MAS） both in rice and maize. For selecting the markers for MAS, sequences presented only in maize rather than in rice were identified by BLAST, and used for primer design using Primer Premier 5.0. A pair of specific primer termed MRpc （Forward： 5＇ AAGCAGGGAAGCGAGACG 3＇, Reverse： 5＇ GATTGCCGCCAGCAGTAG 3＇） was used for selection of transformed rice, and ZmC4Ppc could be highly and constitutively expressed at each tested developmental stages in the transformed rice selected by using MRpc. Thus, MRpc was used for MAS of progenies carrying ZmC4Ppc gene in rice and some restorer lines with ZmC4Ppc （e.g. FPM881） derived from ZmC4Ppc-transformed Kitaake backcrossed with a restorer line Shuhui 881 were obtained. The analyses on genetic background, PEPCase activity, net photosynthetic rate, general combining ability （GCA） and specific combining ability （SCA） of FPM881 showed that similarity of genetic background reached above 95%, the PEPCase and net photosynthetic rate were higher than those of the control, and some of the progenies carrying ZmC4Ppc gene had better GCA and SCA for grain yield per plant, number of panicles per plant, and 1000-grain weight than those of the control. This suggested that the introduction of maize ZmC4Ppc gene via MAS and its stable expression could increase grain yield of rice and would likely provide a pathway for rice varietal improvement.展开更多
The development of high throughput molecular marker technologies and automated scoring of multiple markers simultaneously has opened the possibilities for the development of highly saturated molecular
为提高医疗辅助手术中增强现实系统的虚实配准效率,设计了一种基于海明编码的正六面体三维标识物,对标识物进行检测和识别。针对三维标识物的特点,采用POSIT(Pose from Orthography and Scaling with Iterations)算法求得摄像机的位姿,...为提高医疗辅助手术中增强现实系统的虚实配准效率,设计了一种基于海明编码的正六面体三维标识物,对标识物进行检测和识别。针对三维标识物的特点,采用POSIT(Pose from Orthography and Scaling with Iterations)算法求得摄像机的位姿,并对标识物的尺度进行实验研究,从而得到优化尺度;利用获得的转移矩阵将CT(Computed Tomography)重建并渲染后的虚拟颅骨模型实时显示在真实场景中,最后调整标识物将虚拟模型与真实颅骨模型虚实配准显示。经多组实验验证,设计的三维标识物可在多数情况下识别一个以上标志面,优化后的标识物识别效果良好,可成功地应用在虚实配准实验中,从而证明了这种标识的有效性。展开更多
文摘The full-length of intact Zea mays gene for phosphoenolpyruvate carboxylase gene （ZmC4Ppc） is 6 781 bp. The products of PCR for this gene were not clear with poor repeatability, resulting in that it was difficult for marker-assisted selection （MAS） both in rice and maize. For selecting the markers for MAS, sequences presented only in maize rather than in rice were identified by BLAST, and used for primer design using Primer Premier 5.0. A pair of specific primer termed MRpc （Forward： 5＇ AAGCAGGGAAGCGAGACG 3＇, Reverse： 5＇ GATTGCCGCCAGCAGTAG 3＇） was used for selection of transformed rice, and ZmC4Ppc could be highly and constitutively expressed at each tested developmental stages in the transformed rice selected by using MRpc. Thus, MRpc was used for MAS of progenies carrying ZmC4Ppc gene in rice and some restorer lines with ZmC4Ppc （e.g. FPM881） derived from ZmC4Ppc-transformed Kitaake backcrossed with a restorer line Shuhui 881 were obtained. The analyses on genetic background, PEPCase activity, net photosynthetic rate, general combining ability （GCA） and specific combining ability （SCA） of FPM881 showed that similarity of genetic background reached above 95%, the PEPCase and net photosynthetic rate were higher than those of the control, and some of the progenies carrying ZmC4Ppc gene had better GCA and SCA for grain yield per plant, number of panicles per plant, and 1000-grain weight than those of the control. This suggested that the introduction of maize ZmC4Ppc gene via MAS and its stable expression could increase grain yield of rice and would likely provide a pathway for rice varietal improvement.
文摘The development of high throughput molecular marker technologies and automated scoring of multiple markers simultaneously has opened the possibilities for the development of highly saturated molecular
文摘为提高医疗辅助手术中增强现实系统的虚实配准效率,设计了一种基于海明编码的正六面体三维标识物,对标识物进行检测和识别。针对三维标识物的特点,采用POSIT(Pose from Orthography and Scaling with Iterations)算法求得摄像机的位姿,并对标识物的尺度进行实验研究,从而得到优化尺度;利用获得的转移矩阵将CT(Computed Tomography)重建并渲染后的虚拟颅骨模型实时显示在真实场景中,最后调整标识物将虚拟模型与真实颅骨模型虚实配准显示。经多组实验验证,设计的三维标识物可在多数情况下识别一个以上标志面,优化后的标识物识别效果良好,可成功地应用在虚实配准实验中,从而证明了这种标识的有效性。
文摘利用蒺藜苜蓿(Medicagotruncatula)EST数据库开发新的EST-SSRs标记,分析EST-SSRs的分布特征。利用SSRIT软件对NCBI上公布的285 285条蒺藜苜蓿EST序列进行SSR序列的检测,共检测出6 688个SSR序列,分布于6 512个EST中,占整个EST数据库的2.28%。其中二核苷酸重复基元出现的频率最高,占总EST-SSRs的34.4%(2 301条),其次是三核苷酸重复基元,占29.6%(1 982条),4～6核苷酸重复基元所占比例均较小。利用Pri mer Premier 5.0随机设计100对EST-SSRs引物,PCR扩增结果表明,85对引物在蒺藜苜蓿RIL群体亲本A17和A20上有清晰的扩增条带,占合成引物总数的85%,在RIL-8群体中检测到29个EST-SSRs引物有多态性,占可扩增引物的34.1%。本研究开发了85个蒺藜苜蓿EST-SSRs新标记。
