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31.
利用H(o)lder不等式得到了微分形式的局部 Ar (λ1,λ2 ;Ω)-加权Poincaré型不等式,所得结果能被广泛应用于某些重要方程解的高阶可积性理论. 相似文献
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随着社会生活的现代化进程及建立社会主义市场经济体制带来的深刻社会变革,大学生的价值观念、思维方式、人际关系等都发生了很大变化。在这样复杂的社会环境中,更是要加强对大学生的思想政治教育,使大学生成长为中国特色社会主义事业的合格建设者和可靠接班人。 相似文献
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L-fuzzy相对T-1,相对T0与相对次T0分离性 总被引:1,自引:0,他引:1
李尧龙 《宁夏师范学院学报》2004,25(3):1-5
定义了L-fuzzy拓扑空间中的相对T-1,相对T0与相对次T0分离性,讨论了相对T-1,相对T0与相对次T0分离性的一系列性质.证明了相对T-1,相对T0与相对次T0分离性是遗传的、传递的、弱同胚不变的及可乘性等性质,并给出了一些例子。 相似文献
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综述了无机盐、无机酸、杂多酸(盐)、固体超强酸等催化剂催化合成草莓酯的实验情况.结果表明,硫酸铝、CuCl2 ·2H2 O、固体超强酸SO2 -4 -TiO2 /Al2 O3、活性炭固载硅钨酸等催化剂催化合成草莓酯的收率较高,具有一定的工业应用价值. 相似文献
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S. Negassi 《Research Policy》2004,33(3):365-384
The scope of this paper is to report new empirical evidence on the determinants of R&D co-operation. Indeed, the literature on the capabilities of firms emphasises the role of knowledge in the performance and evolution of firms who use knowledge developed in others to build their own knowledge capital. R&D co-operation between firms is one of the many strategies by which this knowledge may be transmitted. Several theoretical models have stressed that R&D co-operation is more likely when the level of spillovers is high. While this supposition is used in many theoretical models, it has rarely been tested before. Our results do not lend strong support to this intuition. Indeed, our spillover variables (national pure spillovers, national rent spillovers and imports of machine tools), which were supposed to match the theoretical notion of spillovers used in these theoretical models have a positive but not a significant role when explaining R&D co-operation. The R&D co-operation increases with size and with R&D intensity, but not with market share. It also increases with the budget spent on paying license fees and on acquiring patents and labour from foreign firms. In this study, we also analyse the determinants of innovation. In more precise terms, we compare the effects of R&D co-operation to those played by traditional internal factors and those exerted by external, pure and rent spillovers on the innovation capacity of the firms. Our results show that the commercial success of innovations of French firms depends mainly on size, market share, R&D intensity and human capital. Inward FDI from industrialised countries exerts a positive and significant effect. The finding highlights the important role of the absorptive capacity of firms. Spillover measurements, such as the acquisition of machine tools, foreign patents, licenses, and technological opportunities have a positive impact on innovation. 相似文献
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BackgroundCecropin P1, acting as an antimicrobial, has a broad-spectrum antibacterial activity with some antiviral and antifungal properties. It is a promising natural alternative to antibiotics which is originally isolated from the pig intestinal parasitic nematode Ascaris suum. Many studies have shown that Cecropin P1 is helpful for the prevention or treatment of clinical diseases. Therefore, it is very necessary to establish a safe, nontoxic, and efficient expression method of Cecropin P1.ResultsThe results indicated that the recombinant protein was about 5.5 kDa showed by Tricine–SDS–PAGE and Western blot. And Cecropin P1 was efficiently secreted and expressed after 12 h of induction, with an increasing yield over the course of the induction. Its maximum concentration was 7.83 mg/L after concentration and purification. In addition, in vitro experiments demonstrated that Cecropin P1 not only exerted a strong inhibitory effect on Escherichia coli, Salmonella sp., Shigella sp., and Pasteurella sp., but also displayed an antiviral activity against PRRSV NADC30-Like strain.ConclusionsCollectively, the strategy of expressing Cecropin P1 in Saccharomyces cerevisiae is harmless, efficient, and safe for cells. In addition, the expressed Cecropin P1 has antiviral and antibacterial properties concurrently.How to cite: Jiang R, Zhang P, Wu X, et al., Expression of antimicrobial peptide Cecropin P1 in Saccharomyces cerevisiae and its antibacterial and antiviral activity in vitro. Electron J Biotechnol 2021;50. https://doi.org/10.1016/j.ejbt.2020.12.006 相似文献
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随着高等教育规模的扩大,大学城在我国得到了迅速的发展。文章分析了大学城在我国产生的必然性,大学城资源共享的主要领域,提出了大学城图书馆之间可以在政策制定、协调采购、目录编制、馆际互借、对外交流和利用现代信息技术方面实现资源共享,分析了在资源共享方面存在的问题。 相似文献