Subcellular localization of the stripe disease-specific protein encoded by rice stripe virus (RSV) in its vector, the small brown planthopper,Laodelphax striatellus

The stripe disease-specific protein (SP) encoded by the rice stripe virus (RSV) was successfully used as a localization signal of the virus in its vector, the small brown lanthopper,Laodelphax striatellus Fallen. Immunogold particles in large numbers were detected in various parts of the viruliferous females: the ovum, surface of chorion, the midgut lumen, and the columnar cells. Whereas there was none of these particles in the non-viruliferous females and males, and testis of viruliferous males. Endosymbionts (mycetocytes) were abundant, harboring ovaries of both viruliferous and non-viruliferous females, but none in the testis of males. The results provided us with the direct proof that RSV is a ciruculative and propagative plant virus and it was transovarially transmitted alongside with endosymbionts of its vector. Therefore, we deem it a nice lead for future studies on the mechanism of RSV transmission and functioning of its viral proteins.     

电磁继电器触点面的SEM和XPS研究

使用X射线光电子能谱（XPS）和扫描电子显微镜（SEM）等表面分析方法,研究未启封、使用过失失效和使用过失效的继电器触点表面和形貌、组份和结构,结构表明,经过使用后触点表面烧蚀严重并发生磨损,其组份中含Ag、Sn、C和O等原子,C和O的XPS峰显示,触点表面氧化膜和碳化物的形成,导致接触电阻增大,从而影响继电器的稳定履使用寿命。     

Deposition of the platinum crystals on the carbon nanotubes

A new technique and the affecting factors for depositing platinum on the carbon nanotubes were investigated. The results show that the deposited platinum crystals in the atmosphere of hydrogen or nitrogen have a small size and a homogeneous distribution on the surface of the carbon nanotubes. The pretreatment would decrease the platinum particles on the carbon nanotubes significantly.     

Stretching and imaging studies of single DNA molecules

DNA molecules were stretched on silanized mica surface with the molecular combing technique, and detected with fluorescence microscopy and atomic force microscopy. Meantime, DNA molecules were stretched with a modified dynamic molecular combing technique and studied with atomic force microscopy. The results indicate that, compared with the dynamic molecular combing technique, the modified dynamic molecular combing technique has advantages of less-sample demand and less contamination to sample; as compared with the molecular combing technique, it has better aligning effect and reproducibility. Combination of this kind of DNA molecular manipulating technique with the single DNA molecule detecting technique by atomic force microscopy and fluorescence microscopy will play an important role in the basic research of molecular dynamics and the application of gene research.     

多光子近场共焦光学扫描显微镜表面非传播光场的特性研究

对多光子近场共焦光学扫描显微镜非传播光场的特性进行了系统的理论分析。导出了多光子近场共焦光学扫描显微镜表面非传播光场的频率宽与相差的测不准关系表达式及二维的点扩散函数光学传递函数和能量分布表达式。研究结果表明：多光子近场共焦光学扫描显微镜比单光子共焦显微镜具有更高的横向分辨率和纵向分辨率。而多光子近场共焦光学扫描显微镜比双光子共焦显微镜具有更高的空间分辨率。样品置于其表面的非传播光场内,能得最佳的超分辨效果。     

原子力显微镜对二次交联凝胶脱水机理的研究

利用原子力显微镜(AFM)研究了相同聚合物浓度的预凝胶和二次交联凝胶的微观形态结构,通过预凝胶和二次交联凝胶的形貌图对比研究,结果表明,二次交联凝胶的网络状结构上布满细小的“孔隙”和巨大不规则的“空洞”,“空洞”大小可达Zoonm。;综合分析了实验观察结果,对“空洞”的形成机理及二次交联凝胶易脱水机理进行了探讨。     

色氨酸分子在石墨表面吸附的扫描隧道显微镜研究

用扫描隧道显微镜(STM)研究了室温下色氨酸分子(L-Tryptophane)在石墨(HOPG)表面的吸附行为。实验发现,在室温下色氨酸分子可以在石墨表面形成均匀的吸附层,并形成二维条状结构和二维单斜晶格两种有序结构。针对这2种结构给出了可能的吸附模型。这2种有序结构的形成原因被认为与相邻色氨酸分子侧链之间的π堆积相互作用有关。     

NSOM光纤超微探针的拉制及其热动力学研究

采用固定端激光熔拉法拉制NSOM光纤超微探针,系统地研究了控制过程中各条件参数对探针形态的影响,分析了拉制方法的热动力学过程,首次提出了探针控制过程的热动力自恰方程组,并得到了其解析解,理论计算与实验结果基本吻合,总结了光纤超微探针拉制的经验,对解决NSOM光纤超微探针拉制的理论和技术问题具有指导意义。     

偏振共焦扫描显微镜的研制及其成像研究

根据偏振共焦扫描显微镜的原理,成功研制了一台偏振共焦扫描显微镜,用该偏振共焦扫描显微镜对各种集成电路芯片、生物组织等物体进行透射式成像或反射式成像研究,并分析成像结果,实验表明,该偏振共焦扫描显微镜能够对各种物体进行成像,具有成像方式多样,可逐层扫描,非线性成像等特点。     

Cellular internalization of proinsulin C-peptide

Proinsulin C-peptide is known to bind specifically to cell membranes and to exert intracellular effects, but whether it is internalized in target cells is unknown. In this study, using confocal microscopy and immunostained or rhodamine-labeled peptide, we show that C-peptide is internalized and localized to the cytosol of Swiss 3T3 and HEK-293 cells. In addition, transport into nuclei was found using the labeled peptide. The internalization was followed at 37°C for up to 1 h, and was reduced at 4°C and after preincubation with pertussis toxin. Hence, it is concluded to occur via an energy-dependent, pertussis toxin-sensitive mechanism and without detectable degradation within the experimental time course. Surface plasmon resonance measurements demonstrated binding of HEK-293 cell extract components to C-peptide, and subsequent elution of bound material revealed the components to be intracellular proteins. The identification of C-peptide cellular internalization, intracellular binding proteins, absence of rapid subsequent C-peptide degradation and apparent nuclear internalization support a maintained activity similar to that of an intracrine peptide hormone. Hence, the data suggest the possibility of one further C-peptide site of action. Received 31 October 2006; received after revision 27 December 2006; accepted 30 December 2006