本文从中间品贸易和量化分析的角度对中美贸易摩擦及其影响进行了评估。文章首先对中美两国中间品贸易的有关典型事实进行了梳理;然后在Melitz and Ottaviano(2008)的基础上融入了企业进口中间产品行为,通过构建相应的异质性企业模型,...本文从中间品贸易和量化分析的角度对中美贸易摩擦及其影响进行了评估。文章首先对中美两国中间品贸易的有关典型事实进行了梳理;然后在Melitz and Ottaviano(2008)的基础上融入了企业进口中间产品行为,通过构建相应的异质性企业模型,讨论了进口中间产品和最终产品关税变化对一国福利水平的影响。研究发现,一国进口最终产品关税下降,该国福利水平发生恶化,进口中间品关税降低,该国福利水平则有所改善。量化分析的结果表明:(1)与理论预期一致,当美国单方面提高进口中间产品关税时,会恶化其福利水平,进口最终产品关税提高,其福利水平则会改善;(2)受中间品贸易的影响,中美两国爆发贸易摩擦后,两国福利水平均会发生恶化;且与美国相比,中国福利水平的恶化程度更为严重。稳健性检验和后续分析的结果进一步支撑了本文的研究结论。本文的研究从量化分析的角度支撑并论证了贸易自由化对各国福利水平的积极影响。本文建议各方应通过协商及谈判的方式解决双边及多边贸易摩擦,构建公平竞争的贸易格局。展开更多
Chinese medicine （CM） is the most typical conventional therapy compared with any other traditional or alternative medicine systems. The active components of CMs are either primary or secondary metabolites generated ...Chinese medicine （CM） is the most typical conventional therapy compared with any other traditional or alternative medicine systems. The active components of CMs are either primary or secondary metabolites generated by metabolic and biosynthetic enzymes in plants, protecting the plants from environmental stress. The characteristics of these metabolites are diverse, complicated and unique. In this paper, current approaches for quality assessment were extensively reviewed, a new concept of quality marker （Q-marker） was then proposed for CM quality assessment. Additionally, definition of the Q-marker, as well as the relevant methods, were discussed, on the basis of the biosynthetic pathways of secondary metabolites and source of biological active components. Study design of Q-marker is complex system for quality assessment and production process control of CM products with transitivity and traceability. Therefore, the system with characteristics of transmission and traceability is expected to be established for regulation of quality. Upon the concept which the transitivity and traceability in the quality assessment and production process control covered the entire process, such as raw materials, decoction slices, processing, extraction and production can be further enhanced. The transitivity and traceability will inevitably require close attention to ＂who, what, where, when, and why＂ details at each stage of Q-markers of CM production form raw materials to patent product. The establishing quality standards are enablers of many and various transitivity and traceability solutions, not a solution in them. It means that the transitivity and traceability system is readily link between products and across borders in quality. According to the thinking mode and methods of investigation on quality assessment of CM product, we focus on the entire process, in terms of safety and effectiveness and quality control. The standard preparation of CM or CM decoction is not only the basis for study of Q-marker, but also the展开更多
文摘本文从中间品贸易和量化分析的角度对中美贸易摩擦及其影响进行了评估。文章首先对中美两国中间品贸易的有关典型事实进行了梳理;然后在Melitz and Ottaviano(2008)的基础上融入了企业进口中间产品行为,通过构建相应的异质性企业模型,讨论了进口中间产品和最终产品关税变化对一国福利水平的影响。研究发现,一国进口最终产品关税下降,该国福利水平发生恶化,进口中间品关税降低,该国福利水平则有所改善。量化分析的结果表明:(1)与理论预期一致,当美国单方面提高进口中间产品关税时,会恶化其福利水平,进口最终产品关税提高,其福利水平则会改善;(2)受中间品贸易的影响,中美两国爆发贸易摩擦后,两国福利水平均会发生恶化;且与美国相比,中国福利水平的恶化程度更为严重。稳健性检验和后续分析的结果进一步支撑了本文的研究结论。本文的研究从量化分析的角度支撑并论证了贸易自由化对各国福利水平的积极影响。本文建议各方应通过协商及谈判的方式解决双边及多边贸易摩擦,构建公平竞争的贸易格局。
基金National Natural Science Fundantion of China(No.81430096)
文摘Chinese medicine （CM） is the most typical conventional therapy compared with any other traditional or alternative medicine systems. The active components of CMs are either primary or secondary metabolites generated by metabolic and biosynthetic enzymes in plants, protecting the plants from environmental stress. The characteristics of these metabolites are diverse, complicated and unique. In this paper, current approaches for quality assessment were extensively reviewed, a new concept of quality marker （Q-marker） was then proposed for CM quality assessment. Additionally, definition of the Q-marker, as well as the relevant methods, were discussed, on the basis of the biosynthetic pathways of secondary metabolites and source of biological active components. Study design of Q-marker is complex system for quality assessment and production process control of CM products with transitivity and traceability. Therefore, the system with characteristics of transmission and traceability is expected to be established for regulation of quality. Upon the concept which the transitivity and traceability in the quality assessment and production process control covered the entire process, such as raw materials, decoction slices, processing, extraction and production can be further enhanced. The transitivity and traceability will inevitably require close attention to ＂who, what, where, when, and why＂ details at each stage of Q-markers of CM production form raw materials to patent product. The establishing quality standards are enablers of many and various transitivity and traceability solutions, not a solution in them. It means that the transitivity and traceability system is readily link between products and across borders in quality. According to the thinking mode and methods of investigation on quality assessment of CM product, we focus on the entire process, in terms of safety and effectiveness and quality control. The standard preparation of CM or CM decoction is not only the basis for study of Q-marker, but also the
