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排序方式: 共有4014条查询结果,搜索用时 46 毫秒
71.
Mai Morozumi Hirohisa Izumi Takashi Shimizu Yasuhiro Takeda 《Journal of dairy science》2021,104(6):6463-6471
Extracellular vesicles (EV) are important for delivering biologically active substances to facilitate cell-to-cell communication. Milk-derived EV are widely known because of their potential for immune enhancement. However, procedures for isolating milk-derived EV have not been fully established. To obtain pure milk-derived EV and accurately reveal their function, such procedures must be established. The aim of the present study was to compare methods using commercially available kits for isolating milk-derived EV. Initially, we investigated procedures to remove casein, which is the major obstacle in determining milk-derived EV purity. We separated whey using centrifugation only, acetic acid precipitation, and EDTA precipitation. Then, we isolated milk-derived EV by ultracentrifugation, membrane affinity column, size exclusion chromatography (SEC), polymer-based isolation, or phosphatidylserine-affinity isolation. Using EV count per milligram of protein, which is a good indicator of purity, we determined that acetic acid precipitation was the best method for removing casein. Using nanoparticle tracking analysis, protein quantity analysis, and RNA quantity analysis, we comprehensively compared each isolation method for its purity and yield. We found that SEC-based qEV column (Izon Science) could collect purer milk-derived EV at higher quantities. Thus, a combination of acetic acid precipitation and qEV can effectively isolate high amounts of pure extracellular vesicles from bovine milk. 相似文献
72.
To realize the full potential of carbon nanotubes (CNTs) in polymer/CNT nanocomposites, many complicated chemical treatments have been developed to modify the CNTs. Nevertheless, the reinforcing efficiency is still not satisfactory in most cases. In this study, a dramatically improved mechanical enhancement is obtained for polyamide 1010/multiwalled carbon nanotube (MWNT) composites simply by exerting high‐rate drawing and incorporating a commercially available compatibilizer. For the fibers prepared at high draw ratio, their tensile strength and modulus are improved by 137 and 132%, respectively, through adding only 0.5 wt% MWNTs. In particular, the increase in strength is at a very high level for the case of non‐covalent interaction since CNTs could be stretched to failure according to theoretical calculation. It is demonstrated that this reinforcement is mainly attributed to the compatibilizer inducing good dispersion, and the high‐rate drawing inducing strong interfacial interaction and orientation of MWNTs. Copyright © 2012 Society of Chemical Industry 相似文献
73.
74.
High performance β-polypropylene (β-PP) nanocomposites were prepared by nano-CaCO3 with β-nucleation (β-CC) filled PP, and the crystallization and mechanical properties of β-PP nanocomposites were investigated. The results show that β-CC prepared by nano-CaCO3 supported β-nucleating agent calcium pimelate (CaPA) does not only increase the crystallization temperature of PP, but also induce the forming of a number of β-PP. It indicates that the nucleation mechanism of nano-CaCO3 has been changed from α- to β-nucleation. The notched impact strength of β-CC filled PP nanocomposites was higher than that of CC filled PP and CaPA nucleated PP. It is suggested that there is a synergistic effect of toughening of CC and toughness of β-PP. Meanwhile, the reinforcing of CC nanoparticles increased the stiffness of β-PP. The synergistic toughening effect of CC and β-PP was discussed. This method can be extended to prepare other high performance filled β-PP composites. 相似文献
75.
Cloud Based Software Computing as a Service in Hybrid Evolution Algorithm with Feedback Assistance 下载免费PDF全文
Ming-Shen Jian Jun-Hong Shen Kuan-Wei Lee Yi-Chen Jhou Chien-Tang Mai 《电子科技学刊:英文版》2016,14(4):362-369
This paper develops cloud based software computing as a service (SCaaS) in the hybrid evolution algorithm with feedback assistance to solve the data optimal NP-complete problems such as travel salesman problems and job shop scheduling problems. Suitable steps, methods, or procedures of the genetic algorithm can be adopted from various evolution procedures or methods of the genetic algorithms based on the fitness evaluation results and survival ratio of different crossover methods in the current generation. The proposed system can dynamically emphasize the corresponding methods or procedures for the better performance in optimal solution searching. In addition, according to the proposed XML format, system users can upload only the coding of chromosomes without implementing the genetic algorithm program. Furthermore, by using the feedback assistance, the convergence time of the optimal solution can be enhanced. 相似文献
76.
Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related mortality worldwide. New insights into the pathogenesis of this lethal disease are urgently needed. Chromosomal copy number alterations (CNAs) can lead to activation of oncogenes and inactivation of tumor suppressors in human cancers. Thus, identification of cancer-specific CNAs will not only provide new insight into understanding the molecular basis of tumor genesis but also facilitate the identification of HCC biomarkers using CNA. 相似文献
77.
European Journal of Wood and Wood Products - Medium density fibreboards (MDF) are currently not recycled after service life, but various publications report on recycling by the disintegration of... 相似文献
78.
Neural Processing Letters - In this paper, problem of reachable sets bounding is considered for switched neural networks systems with mixed time-varying delays and bounded disturbances. By using... 相似文献
79.
80.
Mengyin Liao Weiping Li Xiping Xi Chenglong Luo Yinxuan Fu Shuanglin Gui Zhaohuan Mai Heng Yan Cheng Jiang 《International Journal of Hydrogen Energy》2017,42(38):24090-24098
This article describes findings of the correlation between the atomic scale surface structure and the electrocatalytic performance of nanoengineered Pt-Pd/C catalysts for oxygen reduction reaction (ORR), aiming at providing a new fundamental insight into the role of the detailed atomic decorated structure of the catalysts in fuel cell reactions. Carbon-supported Pt decorated Pd nanoparticles (donated as Pt-Pd/C), with Pt coverage close to a monolayer, were prepared from a simple galvanic replacement reaction between Pd/C particles and PtCl42? at room temperature. The decorated architecture was confirmed by extensive microstructural characterization techniques, including TEM, XRD, XPS, HAADF-STEM, ICP and HS-LEIS. The catalysts were also examined for their intrinsic kinetic activities towards oxygen reduction reaction. The results have shown that the Pt-Pd/C catalysts are highly active towards molecular oxygen electrocatalytic reduction. These findings have profound implications to the design and nanoengineering of decorated surfaces of catalysts for oxygen reduction reaction. 相似文献