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61.
A polymeric hybrid micelle (PHM) system with highly tunable properties is reported to co‐deliver small molecule and nucleic acid drugs for cancer therapy; this system is structurally simple and easy‐to‐fabricate. The PHM consists of two amphiphilic diblock copolymers, polycaprolactone‐polyethylenimine (PCL‐PEI) and polycaprolactone‐polyethyleneglycol (PCL‐PEG). PHMs are rationally designed with different physicochemical properties by simply adjusting the ratio of the two diblock copolymers and the near neutral PHM‐2 containing a low ratio of PCL‐PEI achieves the optimal balance between high tumor distribution and subsequent cellular uptake after intravenous injection. Encapsulating Hedgehog (Hh) pathway inhibitor vismodegib (VIS) and microRNA‐34a (miR‐34a) into PHM‐2 generates the VIS/PHM‐2/34a co‐delivery system. VIS/PHM‐2/34a shows synergistic anticancer efficacy in murine B16F10‐CD44+ cells, a highly metastatic tumor model of melanoma. VIS/PHM‐2/34a synergistically attenuates the expression of CD44, a vital receptor indicating the metastasis of melanoma. Intriguingly, inhibiting Hh pathway by VIS is accompanied by downregulation of CD44 expression, revealing that Hh signaling might be an upstream regulator of CD44 expression in melanoma. Thus, co‐delivery of miR‐34a and VIS demonstrates great potential in cancer therapy, and PHM offers a structurally simple and highly tunable platform for the co‐delivery of small molecule and nucleic acid drugs in tumor combination therapy.  相似文献   
62.
双检合并技术在海底电缆地震资料处理中被广泛应用,可衰减电缆鬼波的影响。传统方式以水、陆检记录的波场记录相同为假设,电缆鬼波压制效果差,合并效果并不理想。在分析交叉鬼波化双检合并技术基本原理的基础上,综合利用水检资料与陆检鬼波褶积的结果和陆检资料与水检鬼波褶积的结果求取刻度算子,同时在地震资料处理中利用陆检资料标定水检资料,从而优化了交叉鬼波化双检合并技术。实际资料处理结果表明,改进后的技术可有效衰减电缆鬼波,分离出上行波场,大幅度拓宽地震资料频带,提高地震资料分辨率,从而提供更丰富的构造细节信息。  相似文献   
63.
64.
Ni2P nanoparticles and CdS nanorods were grew together on a mesoporous g-C3N4 through a facile in-situ solvothermal approach. Under visible light (λ > 400 nm), the as-prepared ternary PCN–CdS-5% Ni2P composite displays a high H2 evolution rate with 2905.86 μmol g?1 h?1, which is about 14, 18 and 279 times that of PCN–CdS, PCN–Ni2P and PCN, respectively. The enhanced photocatalytic activity is mainly attributed to the improved separation efficiency of the photocarriers by the type II PCN–CdS heterojunction and the effective extraction of photogenerated electrons by Ni2P. Meanwhile, Ni2P acts as co-catalyst to provide the photocatalytic active site for hydrogen reduction. In addition, PCN–CdS-5% Ni2P composite exerts good stability in 12-h cycles.  相似文献   
65.
Hu  Li-Bin  Huang  Xin-Yu  Zhang  Shan  Chen  Xue  Dong  Xian-Hui  Jin  He  Jiang  Zhen-Yu  Gong  Xiao-Ran  Xie  Yi-Xuan  Li  Chen  Chi  Zong-Tao  Xie  Wan-Feng 《Journal of Materials Science: Materials in Electronics》2021,32(19):23728-23736

Morphology transformation and crystal growth strategies of metal oxide semiconductors are still extensively studied in material science recently, because the morphology and crystallinity significantly affect the physicochemical characteristics of metal oxide nanomaterials. However, understanding the morphology changes of α-MoO3 induced by annealing is still a challenge. Herein, the nanostructure transition of α-MoO3 induced by the annealing temperature is carefully investigated via the XRD and SEM methods. It can be found that crystallization is highly dependent on the annealing temperature. Interestingly, the MoO3 nanoflowers can change into nanosheets at 500 °C. Afterward, the nanosheets turned into microrods with the increase in annealing temperature due to the continuous growth of MoO3 crystal. On the other hand, the sensing performances of various MoO3 nanostructures are studied toward ethanol gas. Compared to the MoO3 nanoflowers and microrods, the MoO3 nanosheets-based sensor exhibits superior sensing performance to ethanol, and the maximum response value is 8.06.

  相似文献   
66.
International Journal of Mechanics and Materials in Design - Conform and non-conformal contact problem in the face of piezoelectric motors can be hard to grasp, especially both the friction drive...  相似文献   
67.
中俄东线天然气即将引入中国,将对东北地区的天然气利用项目产生有力的推动作用,同时也将面临各种问题。为建立长期可持续发展资源供应体系,结合能源供需实际,讨论了俄气到来后,东北地区天然气未来的发展方向,并分析了存在的主要问题:①天然气自产不足,域外依存度高;②地域特点决定替代能源可有多种选择;③调峰困难且富余天然气难以处理;④天然气替代经济性差,价高难以承受。并针对矛盾点进行了总结,指出来源多元化和资源多样化才能可持续发展。明确东北地区宜以天然气作为过渡能源,并提出了适宜地区经济发展的天然气利用建议。  相似文献   
68.
Wireless Personal Communications - This paper presents an error detection algorithm for Lempel-Ziv-78 (LZ78) compressed data. LZ78 data compression involves dictionary coding and aims to compress...  相似文献   
69.
本文对燃气轮机发电机组整机的投资模型进行了分析,结合2018 Gas Turbine Word (GTW)handbook的数据对燃气轮机整机投资模型进行了更新,并给出了燃气-蒸汽联合循环的的单变量、双变量投资模型。无论对燃气轮机整机还是联合循环,采用幂函数的投资模型都优于对数函数,而单变量和双变量投资模型的精度相当。采用幂函数单变量或者双变量的投资模型都可以实现全功率范围误差10%以内的投资估算。  相似文献   
70.
Fermented milks were prepared with various culture combinations of Lactobacillus plantarum or Bifidobacterium animalis with Streptococcus thermophilus, and the impact of microbes combinations on acidification, proteolysis, lipolysis, texture, volatiles and sensory quality of fermented milk was investigated during 21-day storage at 4 °C. The results showed that products from the co-cultures displayed higher titratable acidity, more peptides, higher proteolytic activity and lipolysis capacity compared with that from the pure strains of S. thermophilus. When L. plantarum and B. animalis combined in a ratio of 2:1 with S. thermophilus, the products maintained relatively more viable cell counts of the 3 strains, strong proteolysis ability and lipolysis capacity during the storage. Milk fermented by co-cultures of the 3 strains exhibited higher cohesiveness, more volatiles and better sensory quality compared with these fermented by S. thermophilus only or in co-cultures with either B. animalis or L. plantarum based on principal component analysis.  相似文献   
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