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61.
基于基库的多实化视图增量维护算法 总被引:1,自引:0,他引:1
基于基库的多实化视图维护将基库集作为多个实化视图的辅助视图集保存在集成端。当信息源发生变化时,基库随着更新,同时触发多实化视图的更新与维护。在保存基库的情况下,多实化视图的维护无需访问信息源就可完成,是多实化视图的自维护方式。 相似文献
62.
XScale架构分析及优化策略 总被引:1,自引:0,他引:1
XScale被广泛地应用于嵌入式系统,但是很多程序并没有充分利用XScale架构的各种优点,性能并不尽如人意。本文详细分析了IntelXScale架构,并提出如何基于XScale架构进行优化的策略,最后对实际应用程序进行优化,并给出测试结果。 相似文献
63.
Keng-Liang Ou Chiung-Fang Huang Wen-Chien Lan Bai-Hung Huang Hsu-An Pan Yung-Kang Shen Takashi Saito Hsin-Yu Tsai Yung-Chieh Cho Kuo-Sheng Hung Hsin-Hua Chou 《International journal of molecular sciences》2022,23(3)
The ability of Pluronic F127 (PF127) conjugated with tetrapeptide Gly-Arg-Gly-Asp (GRGD) as a sequence of Arg-Gly-Asp (RGD) peptide to form the investigated potential hydrogel (hereafter referred to as 3DG bioformer (3BE)) to produce spheroid, biocompatibility, and cell invasion ability, was assessed in this study. The fibroblast cell line (NIH 3T3), osteoblast cell line (MG-63), and human breast cancer cell line (MCF-7) were cultured in the 3BE hydrogel and commercial product (Matrigel) for comparison. The morphology of spheroid formation was evaluated via optical microscopy. The cell viability was observed through cell counting Kit-8 assay, and cell invasion was investigated via Boyden chamber assay. Analytical results indicated that 3BE exhibited lower spheroid formation than Matrigel. However, the 3BE appeared biocompatible to NIH 3T3, MG-63, and MCF-7 cells. Moreover, cell invasion ability and cell survival rate after invasion through the 3BE was displayed to be comparable to Matrigel. Thus, these findings demonstrate that the 3BE hydrogel has a great potential as an alternative to a three-dimensional cell culture for drug screening applications. 相似文献
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Weiti Cui Zihan Zhuang Peihao Jiang Jincheng Pan Gan Zhao Sheng Xu Wenbiao Shen 《International journal of molecular sciences》2022,23(14)
Cinnamoyl-CoA reductase (CCR) is a pivotal enzyme in plant lignin synthesis, which has a role in plant secondary cell wall development and environmental stress defense. Alfalfa is a predominant legume forage with excellent quality, but the lignin content negatively affects fodder digestibility. Currently, there is limited information on CCR characteristics, gene expression, and its role in lignin metabolism in alfalfa. In this study, we identified 30 members in the CCR gene family of Medicago sativa. In addition, gene structure, conserved motif, and evolution analysis suggested MsCCR1–7 presumably functioned as CCR, while the 23 MsCCR-likes fell into three categories. The expression patterns of MsCCRs/MsCCR-likes suggested their role in plant development, response to environmental stresses, and phytohormone treatment. These results were consistent with the cis-elements in their promoters. Histochemical staining showed that lignin accumulation gradually deepened with the development, which was consistent with gene expression results. Furthermore, recombinant MsCCR1 and MsCCR-like1 were purified and the kinetic parameters were tested under four substrates. In addition, three-dimensional structure models of MsCCR1 and MsCCR-like1 proteins showed the difference in the substrate-binding motif H212(X)2K215R263. These results will be useful for further application for legume forage quality modification and biofuels industry engineering in the future. 相似文献
66.
同轴度测量误差的分析与探讨 总被引:1,自引:0,他引:1
详细分析测量同轴度误差的近似计算方法的误差规律及其影响因素,指出测量同轴度误差的合理及不合理的采样位置,为同轴度误差测量过程中的数据采样提供依据。 相似文献
67.
Bao Wan Xiao-Qiang Li Cun-Liang Pan Dong-Yu Li Sheng-Guan Qu Chao Yang 《稀有金属(英文版)》2021,(8):2134-2142
For the purpose of elevated temperature service and weight reduction in aerospace vehicle applications,a novel Ti-Zr-Fe-Cu-Ni-Co-Mo filler metal was employed to... 相似文献
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