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The key to promoting the EPC (Engineering, Procurement, Construction) model in China's public construction projects is to alter the path dependence of a project owner's choice of project delivery model (PDM). This study uses evolutionary game theory to discuss the mechanism of government incentives as an external motivation to alter path dependence in the PDM. In addition, a cellular automata simulation to examine the influence of various government incentives on the project owner's choice. The results show that the combination of subsidies and penalties can produce the best incentive. Subsidies are more effective at promoting PDM institutional change, whereas penalties are more effective at preventing PDM institutional change from anti-recession effects. Based on our results, we propose that the Chinese government should take active subsidy measures at the initial stage of EPC promotion, and adopt a dynamic incentive strategy of continuously reducing subsidies and increasing penalties according to the improvement of the development degree of EPC model. [ABSTRACT FROM AUTHOR]

Rab1, a GTPase, is present in all eukaryotes, and is mainly involved in vesicle trafficking between the endoplasmic reticulum and Golgi, thereby regulating many cellular activities and pathogenic infections. However, little is known of how Rab1 functions in fish during virus infection. Groupers (Epinephelus spp.) are high in economic value and widely cultivated in China and Southeast Asia, although they often suffer from diseases. Red-spotted grouper nervous necrosis virus (RGNNV), a highly pathogenic RNA virus, is a major pathogen in cultured groupers, and causes huge economic losses. A series of host cellular proteins involved in RGNNV infection was identified. However, the impact of Rab1 on RGNNV infection has not yet been reported. In this study, a novel Rab1 homolog (EcRab1) from Epinephelus coioides was cloned, and its roles during virus infection and host immune responses were investigated. EcRab1 encoded a 202 amino acid polypeptide, showing 98% and 78% identity to Epinephelus lanceolatus and Homo sapiens , respectively. After challenge with RGNNV or poly(I:C), the transcription of EcRab1 was altered both in vitro and in vivo , implying that EcRab1 was involved in virus infection. Subcellular localization showed that EcRab1 was displayed as punctate structures in the cytoplasm, which was affected by EcRab1 mutants. The dominant negative (DN) EcRab1, enabling EcRab1 to remain in the GDP-binding state, caused EcRab1 to be diffusely distributed in the cytoplasm. Constitutively active (CA) EcRab1, enabling EcRab1 to remain in the GTP-binding state, induced larger cluster structures of EcRab1. During the late stage of RGNNV infection, some EcRab1 co-localized with RGNNV, and the size of EcRab1 clusters was enlarged. Importantly, overexpression of EcRab1 significantly inhibited RGNNV infection, and knockdown of EcRab1 promoted RGNNV infection. Furthermore, EcRab1 inhibited the entry of RGNNV to host cells. Compared with EcRab1, overexpression of DN EcRab1 or CA EcRab1 also promoted RGNNV infection, suggesting that EcRab1 regulated RGNNV infection, depending on the cycles of GTP- and GDP-binding states. In addition, EcRab1 positively regulated interferon (IFN) immune and inflammatory responses. Taken together, these results suggest that EcRab1 affects RGNNV infection, possibly by regulating host immunity. Our study furthers the understanding of Rab1 function during virus infection, thus helping to design new antiviral strategies. • EcRab1 was obviously downregulated after RGNNV infection. • EcRab1 significantly inhibited RGNNV infection. • EcRab1 inhibits RGNNV entry, which was the first report of the effect of Rab1 on virus entry. • EcRab1 has a positive regulatory effect on host immunity. [ABSTRACT FROM AUTHOR]

Rab20, a member of the Rab GTPase family, associates with membrane trafficking and immune response, which play important roles in bacteria control. However, little is known about the role of Rab20 during virus infection. Groupers (Epinephelus spp.) with high economic value are widely cultured in China and Southeast Asian countries. However, the cultured groupers have suffered from diseases caused by viruses such as Singapore grouper iridovirus (SGIV) resulting in huge economic losses. In this study, the roles of a novel Rab20 homolog (EcRab20), from orange-spotted grouper (Epinephelus coioides), on the infection of SGIV and host immune response were investigated. EcRab20 showed high sequence identity with other Rab20 from mammals to fishes. In healthy groupers, EcRab20 was predominantly expressed in immune organs, such as kidney, liver and spleen. After SGIV infection, the expression of EcRab20 in spleen was significantly up-regulated. Confocal imaging showed that EcRab20 distributed in the cytoplasm as punctate and vesicle-like structures, which was destructed by overexpression of the dominant negative EcRab20 (DN EcRab20). Moreover, EcRab20 notably colocalized with Golgi and early endosomes, partly colocalized with endoplasmic reticulum and late endosomes, but did not colocalize with mitochondria or lysosome. Ultimately, overexpression of EcRab20 significantly inhibited SGIV infection, whereas overexpression of DN EcRab20 promoted SGIV infection. Furthermore, using single particle imaging analysis, we found that EcRab20 or DN EcRab20 had no effect on the entry of SGIV. In addition, EcRab20 positively regulated the IFN immune and inflammatory responses. Taken together, these results demonstrated that EcRab20 affect SGIV infection by regulating the host immunity, providing a new idea of the anti-virus mechanisms of Rab20 against SGIV infection and contributing to design new antiviral strategies. • It is the first time to explore the interaction between Rab20 and virus infection. • After SGIV infection in spleen, EcRab20 is significantly up-regulated. • EcRab20 significantly inhibits SGIV infection, without affecting SGIV entry. • The host immunity is positively regulated by EcRab20. [ABSTRACT FROM AUTHOR]

In this study, a spatiotemporal estimation method based on Funk singular value decomposition (F-SVD) that considers the spatiotemporal correlation of rainfall is proposed to improve estimations from gauge observations. Hourly rainfall data of several flood events are selected to verify the proposed method by comparing with Inverse Distance Weighting (IDW) and Ordinary Kriging (OK) in Hanjiang basin, China. The results show that (1) F-SVD has the best performance in rainfall estimation, the larger the amount of rainfall event, the greater the improvement of F-SVD method as compared to OK and IDW; (2) through the combination/integration with F-SVD, the accuracy of IDW and OK can be greatly improved. Therefore, F-SVD can be employed as a practical method to estimate rainfall spatial distribution, which is essential data for regional hydrological modelling and water resource analysis. • A spatiotemporal estimation method based on F-SVD is proposed to estimate rainfall using gauge observation. • F-SVD is utilized to decompose the spatiotemporal matrix consisted of rainfall data. • F-SVD has higher accuracy and lower uncertainty compared to OK and IDW. • Through combination with F-SVD, the accuracy of IDW and OK can be greatly improved. • It is a practical method to process data for regional hydrological modelling. [ABSTRACT FROM AUTHOR]