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991.
Cloning, Characterization, and Expression Analysis of Calreticulin from Pearl Oyster Pinctada fucata
Calreticulin is a unique calcium-binding protein with multiple functions mostly located in the sarcoplasmic/endoplasmic reticulum. A large amount of calcium is absorbed from the medium and transported to mineralization sites during biomineralization in pearl oyster. This paper describes the cloning of the full-length cDNA of calreticulin from Pinctada fucata, namely PCRT. PCRT encodes a deduced 414-amino acid protein, which includes a predicted 17- amino acid signal peptide and an endoplasmic reticulum retrieval sequence HDEL. The protein shows 63%-76% sequence identity and shares some common characteristics with calreticulins from other species. Semi-quantitative RT-PCR indicates that PCRT is ubiquitously expressed in all tissues tested with the highest expression in the hemolymph and the mantle. In situ hybridization analysis of PCRT in the mantle showed strong signals in the inner fold, the inner side of middle fold, and the inner side of outer fold of the mantle epithelium, All these results suggest PCRT might be involved in Ca^2+ transport and storage during oyster biomineralization. 相似文献
992.
This paper reports observations of passenger flow in the Wuchang railway station in Wuhan, China during the Chinese Traditional Spring Festival in 2006. The data collected are used to verify a crowd dynamics model previously developed. The crowd dynamics model is based on simulating the global movement of each individual under the influence of the surrounding crowd, and the good agreement between the predictions and observations validates the prediction model. The crowd dynamics model suggests that the crowd movement speed is dominated by two factors: the front-back inter-person effect, and the pedestrian's self-motive. The first effect gives logarithmic relationship between the crowd speed and crowd density. The second factor depends on the individual motive driven with which people try to divorce themselves from the control of the crowd movement. The prediction model are helpful to guide the design of public traffic systems for effective crowd dispersal. 相似文献
993.
Based on the practical application of Geology Information System(GIS) throughout the world, combined with the characters of
road’s geological hazard and it’s supervision, the paper introduces on the importance of the research on road’s geological
hazards information management and decision-making support system. The paper also analyzes the system’s target, the principles
and key techniques in developing the system. In the research, we developed the GIS-based road’s geological hazard information
management and decision-making support system and applied it to one speedway in the west of China where contains typical geological
hazards. The system based on the database of road’s geological hazard on the grounds of spatial graphic information and attribute
information. By virtue of the scientific assessment and prediction mathematical model, integrating the GIS’s strongpoint on
spatial analyzing, the system is capable of visualizing the regionalization of road according to the geological hazards it
contains, and accurately assessing and predicting geological hazards, thus efficiently assists the road construction and management
units in the decision making on controlling the geological hazards and reducing the related loss.
Biography: WANG Weidong (1971–), male, Associate professor, Ph.D. candidate, research direction: road and railway engineering, management
science and engineering. 相似文献
994.
Zi Fang Zhenguang Yan Shuo Li Qin Wang Weizhong Cao Guangrui Xu Xunhao Xiong Liping Xie Rongqing Zhang 《自然科学进展》2008,18(4):405-412
Calmodulin (CaM) and calmodulin-like protein (CaLP) are two proteins involved in biomineralization. Their localizations in Pinctada fucata mantle epithelia were studied by Western blot (WB) analysis of the nuclear/cytosol fraction of primary cultured Pinctada fucata mantle cells and immunogold electron microscopy. The results showed a completely different distribution of these two proteins at the subcellular level. CaM was distributed throughout both the nucleus and cytoplasm of the mantle epithelium but CaLP was distributed only in the cytoplasm. The functions of these two proteins in biomineralization were investigated by shell regeneration. During this process, the expressions of CaM and CaLP were greatly enhanced in different organelles of the mantle epithelium. Overexpression of these two proteins and a mutant of calmodulin-like protein (M-CaLP) that lacks an extra C-terminal tail in MC3T3-E1 promoted the mRNA expression of osteopontin, a biomineralization marker for osteoblasts. All of the results indicated that CaM and CaLP have completely different distributions in the mantle epithelium and affect the biomineralization process at different levels. The extra C-terminal tail of CaLP is important for its functions in biomineralization in Pinctada fucata. 相似文献
995.
模仿的定义、重要性及其分类 总被引:2,自引:0,他引:2
目的是总结模仿研究领域的主要研究成就,以为未来的学术研究建立坚实的基础。总结了模仿领域三个关键问题上的研究进展,即模仿的定义、重要性及其分类。与此同时,指出了目前关于模仿研究的三个误区。 相似文献
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采用热膨胀仪研究了MgO-PSZ陶瓷材料的热膨胀特性.试样在一定条件下烧结,经550~950 ℃热处理后发生了明显的单斜相→四方相相变,此低温相变降低了MgO-PSZ的热膨胀率,其相变产生的体积收缩与受热产生的体积膨胀相互抵消,使试样表现出零膨胀特性,从而改善了材料的抗热震性能. 相似文献
1000.
钢水测氧过程锆管温度场的有限元分析 总被引:1,自引:0,他引:1
采用ANSYS软件对钢水测氧过程中测头插入钢水10 s瞬间锆管热传导过程进行模拟分析.结果表明,模拟锆管达到稳定温度的时间与实测得的温度/电动势曲线的响应时间基本相符.对不同壁厚和内径的锆管插入钢水后温度达到稳定的时间进行比较,得出厚度、内径与锆管管头、管壁内温度达到稳定时间之间的相关关系. 相似文献