In this study, composite nanofibers (SF/PCL/CS) for the application of dressings were prepared with silk fibroin (SF), polycaprolactone (PCL), and chitosan (CS) by electrospinning techniques, and the effect of the fiber diameter was investigated using the three-stage Taguchi experimental design method (L9). Nanofibrous scaffolds were characterized by the combined techniques of scanning electron microscopy (SEM) and transmission electron microscopy (TEM), a cytotoxicity test, proliferation tests, the antimicrobial activity, and the equilibrium water content. A signal-to-noise ratio (S/N) analysis indicated that the contribution followed the order of SF to PCL > flow rate > applied voltage > CS addition, possibly owing to the viscosity and formation of the beaded fiber. The optimum combination for obtaining the smallest fiber diameter (170 nm) with a smooth and uniform distribution was determined to be a ratio of SF to PCL of 1:2, a flow rate of 0.3 mL/hr, and an applied voltage of 25 kV at a needle tip-to-collector distance of 15 cm (position). The viability of these mouse fibroblast L929 cell cultures exceeded 50% within 24 hours, therefore SF/PCL/CS could be considered non-toxic according to the standards. The results proposed that the hydrophilic structure of SF/PCL/CS not only revealed a highly interconnected porous construction but also that it could help cells promote the exchange of nutrients and oxygen. The SF/PCL/CS scaffold showed a high interconnectivity between pores and porosity and water uptake abilities able to provide good conditions for cell infiltration and proliferation. The results from this study suggested that SF/PCL/CS could be suitable for skin tissue engineering.

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The Chinese government is paying attention to the development of new agricultural business entities and improving green finance is a key to achieve the goal of rural revitalization. The study depends on both primary analysis based on semi-structured interviews and secondary analysis obtained from government reports, annual reports, published articles and academic papers to find out what can be learned from the experience in the UK. From analysis, this study found three major lessons that can be learned from the UK’s practice, including to develop a proper green financial regulatory system, to build a more mature market transaction system and to construct a more transparent green information sharing platform. Besides, the commercial banks in China need to deal with four challenges in the process of expanding green finance.

Through a brief introduction of the current application of lightweight materials in the automotive market, it is proposed that carbon fibre composites are a promising application. Therefore, it is constructive to study the advantages and disadvantages of the application and then put forward suggestions for improvement.