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Based on previous microarray result of Brassica napus(heterozygous pairs of dominant male sterile line) and Arabidopsis thaliana genome,a differentially expressed B.napus gene Bn19070 which demonstrated high homology with At2g19070 emerged. It was well expressed in fertile stem with low expression level in male sterile stem. To understand Bn19070's function,amiRNA(artificial microRNA) gene silencing technique was used to disable the function of homologous gene At2g19070. Two interference targets from At2g19070 mRNA were selected and transformed into Arabidopsis. amiRNAi (amiRNA interference)phenotypes related to male sterility were observed in transgenic Arabidopsis, including decreased microspore number, deteriorated anther and fruitless. Expressions of both targets decreased remarkably (more than 90%) in T2 lines with similar phenomena. Results indicated the flexibility of amiRNAi intarget site selection. The interference research of At2g19070 would contribute to Bn19070 genestudy. [ABSTRACT FROM AUTHOR]

Based on previous analysis of microarray expression on Brassica napus homozygous pairs of dominant male sterile line, a differentially expressed Brassica napus gene (BnROP1) which is homologous to At3 G5 1300 (AtROP1) was selected. Method of fluorescent quantitative PCR was used to analyze the expression pattern of Bn-ROP1 in different tissues of B. napus, including root, stem, leaves, flower, pistil, stamen and silique. The results indicated that BnROP1 was highly expressed in fertile flower and stamen. On this basis, microRNA interference vector was constructed and then transformed into Arabidopsis thaliana by Agrobacterium, obtaining 12 transgenic seedlings. The phenotype of T1 transgenic generation was observed during florescence. Most transgenic seedlings showed reduction or disappearance of siliques, no pollen, short filaments, deteriorated anther and microspore. These phenomena indicated that these seedlings were fully - sterile or semi - sterile. The fluorescence quantitative PCR experiments on T2 generations of transgenic lines showed that the expression level of target gene decreased sig- nificantly. The correlation of transgenic male sterile phenotype and the silencing of ROP1 expressing indicated that ROP1 was not only promoting tip growth and maintaining growth polarity in pollen tubes but was also essential for plant fertility. [ABSTRACT FROM AUTHOR]

The micromachined gyroscope with an electromagnetic levitated rotor (MGELR) was modeled and analyzed using finite element, and the influence of loop number, depth and inner diameter of levitation coil on levitating force was obtained. With the increase of the loop number of levitation coil, the levitating force increases more quickly. The levitating force decreases with the increase of the depth of coil. The levitating force increases linearly with the increase of the inner diameter of levitation coil. The micromachining process like photolithograph, electroplate and sputtering etc is adopted to fabricate the stator of MGELR. The result of preliminary experiment shows that the design scheme of MGELR is feasible. The multi-loop levitation coil structure was adopted and the influencing factor of levitating force was analyzed systematically. [ABSTRACT FROM AUTHOR]

To improve the motion precision and torque output of an omni-directional microrobot, a virtual coil method was adopted. This virtual coil instead of mechanical structure control method is designed to overcome the restricts of MEMS process, increase the torque output of electromagnetic micromotor and realize the microrobot motion precision control. The results show that the microrobot is more powerful and can be applied in many fields. [ABSTRACT FROM AUTHOR]