Geological conditions and key rock mechanics issues in the Western Route of South-to-North Water Transfer Project

In terms of special geological conditions of the Western Route of South-to-North Water Transfer Project, the classification method for surrounding rocks is discussed by combining with the construction method of tunnel boring machine （TBM）. The classification standard of surrounding rocks is put forward on the basis of physical simulations and engineering practices. Damage, deformation and evolution of surrounding rocks induced by TBM excavation are discussed. Meanwhile, the long-term deformation mechanisms and stability of surrounding rocks are also studied. On this basis, a three-dimensional constitutive model for interbedded sandstone slate and a fiat shell-joint element-foundation system for calculating internal forces of segment lining are established. The deformation features of surrounding rocks of deep and steep interbedded sandstone slate and their influences on internal forces of segment lining are presented. Finally, the design methods of segment lining constructed in deep and steep flysch are proposed.

Heterogeneous expectations,IPO Underpricing and issuing mechanism

Background:Compared with the fixed-price mechanism,the bookbuilding mechanism has not changed the Chinese IPO high underpricing.How to develop scientific and reasonable IPO pricing,and reduce the high IPO underpricing has become a major challenge for China's securities market.Methods:In this paper,using behavioral finance theory and game theory,we build the Initial public offering(IPO)pricing and underpricing models with investors’heterogeneity based on different issuing mechanisms and provide a comparative analysis.Results:Firstly,our models show that IPO underpricing will not be eliminated by using either fixed-price or bookbuilding mechanisms,but when the investors’heterogeneity expectation is the same,lower IPO underpricing can be obtained by the issuing of bookbuilding compared with that of fixed price.Secondly,the IPO underpricing may be larger than that under fixed price if the heterogeneity of investors under bookbuilding is larger than that under fixed price.Thirdly,the numerical analysis results provide strong support for our model.Conclusions:These findings further explains the cause of the high IPO underpricing long-standing in China.

Recent Progress in Understanding the Mechanisms of Pain and Itch:the Second Special Issue

In 2012, we published the first special issue on mechanisms of pain and itch in Neuroscience Bulletin, which covered the peripheral, central, and glial mechanisms of pain and itch [1-5]. In the last 5 years, the field has seen tremendous progress in the molecular and functional characterization of primary sensory neurons [6, 7], neurocircuits of pain and itch [8-10], immune and glial modulation of pain and itch [11-15], molecular mechanisms of pain [16, 17], and identification of brain signatures of pain [18]. Thus, it is timely to highlight the recent progress in a second special issue. I invited the previous authors and new authors from China, the USA, and Japan, and they have contributed 20 mini-reviews and original articles to this special issue.