The effect of tourism on water environments has received a high degree of interest in the study of eco-tourism.Based on the analysis of the relationship between tourist activities and the water environment in the Liup...The effect of tourism on water environments has received a high degree of interest in the study of eco-tourism.Based on the analysis of the relationship between tourist activities and the water environment in the Liupan Mountain eco-tourism zone,the case study area,a Water Environment of Tourism Area Model(WETAM) is built to simulate the temporal and spatial changes in water quality and the response saturation thresholds under four sewage treatment scenarios.The results imply the following:(1) WETAM performs well in modeling a water environment to represent the dynamic process of water quality change in response to tourist activities.(2) Under four sewage treatment scenarios(fundamental,low,medium,and high),the threshold shows an obvious uptrend.(3) The response threshold of water quality with respect to the interference of tourist activities fluctuates seasonally due to changes in tourist density.(4) The thresholds differ significantly among five tourism functional areas.According to the response saturation threshold of the water environment,effective control based on the scale and intensity of tourist activities is important for a successful transformation of this tourism destination's development strategies.Therefore,the integrated management of water pollution in tourism areas plays a crucial role in sustainable tourism development.展开更多
Debris flows are the one type of natural disaster that is most closely associated with hu- man activities. Debris flows are characterized as being widely distributed and frequently activated. Rainfall is an important ...Debris flows are the one type of natural disaster that is most closely associated with hu- man activities. Debris flows are characterized as being widely distributed and frequently activated. Rainfall is an important component of debris flows and is the most active factor when debris flows oc- cur. Rainfall also determines the temporal and spatial distribution characteristics of the hazards. A reasonable rainfall threshold target is essential to ensuring the accuracy of debris flow pre-warning. Such a threshold is important for the study of the mechanisms of debris flow formation, predicting the characteristics of future activities and the design of prevention and engineering control measures. Most mountainous areas have little data regarding rainfall and hazards, especially in debris flow forming re- gions. Therefore, both the traditional demonstration method and frequency calculated method cannot satisfy the debris flow pre-warning requirements. This study presents the characteristics of pre-warning regions, included the rainfall, hydrologic and topographic conditions. An analogous area with abundant data and the same conditions as the pre-warning region was selected, and the rainfall threshold was calculated by proxy. This method resolved the problem of debris flow pre-warning in ar- eas lacking data and provided a new approach for debris flow pre-warning in mountainous areas.展开更多
Radioimmunoassay was employed to dctermine the immunorcactivc met-enkephalin(ir-MEK)contents of several brain regions .The pain threshold(PT)andir-MEK content of striatum and hypothalamus increased markedly afterintra...Radioimmunoassay was employed to dctermine the immunorcactivc met-enkephalin(ir-MEK)contents of several brain regions .The pain threshold(PT)andir-MEK content of striatum and hypothalamus increased markedly afterintraoerebroventricular injection of substance P(SP)in the dosage of lμgg/10μl ,but nosignificant change of ir-MEK content in hippocampus was observed.When theperiaqueductal gray(PAG)was destroyed with electrolysis,the increase of PT andir-MEK content in the two brain regions after SP injection was obviouslysuppressed(P【0.05-0.01).The PT and ir-MEK content of hypothalamus andstriatum would also increase after intra-PAG injection of SP(0.4μg/4μl),electroacupuncture or intraperitoneal injection of morphine.The ir-MEK content ofhippocampus could also increase after intra-PAG injection of SP or intraperitoncal injec-tion of morphine.The combination of intra-PAG injection of SP andelectroacupuncture caused a more marked elevation of PT and ir-MEK content of the 3brain regions than either of the two used singly could(P【0.01 ).The combined effect ofintra-PAG injection of SP and intraperitoneal injection of morphine was similar to thatof either of the two used singly(P】0.05).These facts indicate that thc analgesic effect ofSP activated by PAG was mediated through the increase of cerebral met-cnkcphalin con-tent,and there was a synergic effect between SP and elcctroacupuncturc.展开更多
In this article, we use the unrestricted two-regime autoregressive threshold model to test both nonlinearity and stationarity of China's real exchange rate against its Hong Kong and Macao special administrative re...In this article, we use the unrestricted two-regime autoregressive threshold model to test both nonlinearity and stationarity of China's real exchange rate against its Hong Kong and Macao special administrative regions(SARs). Our main finding is that China's real exchange rate is neither linear nor stationary, indicating that the purchasing power parity does not hold between China Mainland and its two SARs, which implies, to certain extent, the three economies may not meet the condition of constituting an optimal currency area.展开更多
基金supported by the National Natural Science Foundation of China(Project No.40971299)
文摘The effect of tourism on water environments has received a high degree of interest in the study of eco-tourism.Based on the analysis of the relationship between tourist activities and the water environment in the Liupan Mountain eco-tourism zone,the case study area,a Water Environment of Tourism Area Model(WETAM) is built to simulate the temporal and spatial changes in water quality and the response saturation thresholds under four sewage treatment scenarios.The results imply the following:(1) WETAM performs well in modeling a water environment to represent the dynamic process of water quality change in response to tourist activities.(2) Under four sewage treatment scenarios(fundamental,low,medium,and high),the threshold shows an obvious uptrend.(3) The response threshold of water quality with respect to the interference of tourist activities fluctuates seasonally due to changes in tourist density.(4) The thresholds differ significantly among five tourism functional areas.According to the response saturation threshold of the water environment,effective control based on the scale and intensity of tourist activities is important for a successful transformation of this tourism destination's development strategies.Therefore,the integrated management of water pollution in tourism areas plays a crucial role in sustainable tourism development.
基金supported by the National Natural Science Foundation of China(Nos.40830742 and 40901007)
文摘Debris flows are the one type of natural disaster that is most closely associated with hu- man activities. Debris flows are characterized as being widely distributed and frequently activated. Rainfall is an important component of debris flows and is the most active factor when debris flows oc- cur. Rainfall also determines the temporal and spatial distribution characteristics of the hazards. A reasonable rainfall threshold target is essential to ensuring the accuracy of debris flow pre-warning. Such a threshold is important for the study of the mechanisms of debris flow formation, predicting the characteristics of future activities and the design of prevention and engineering control measures. Most mountainous areas have little data regarding rainfall and hazards, especially in debris flow forming re- gions. Therefore, both the traditional demonstration method and frequency calculated method cannot satisfy the debris flow pre-warning requirements. This study presents the characteristics of pre-warning regions, included the rainfall, hydrologic and topographic conditions. An analogous area with abundant data and the same conditions as the pre-warning region was selected, and the rainfall threshold was calculated by proxy. This method resolved the problem of debris flow pre-warning in ar- eas lacking data and provided a new approach for debris flow pre-warning in mountainous areas.
文摘Radioimmunoassay was employed to dctermine the immunorcactivc met-enkephalin(ir-MEK)contents of several brain regions .The pain threshold(PT)andir-MEK content of striatum and hypothalamus increased markedly afterintraoerebroventricular injection of substance P(SP)in the dosage of lμgg/10μl ,but nosignificant change of ir-MEK content in hippocampus was observed.When theperiaqueductal gray(PAG)was destroyed with electrolysis,the increase of PT andir-MEK content in the two brain regions after SP injection was obviouslysuppressed(P【0.05-0.01).The PT and ir-MEK content of hypothalamus andstriatum would also increase after intra-PAG injection of SP(0.4μg/4μl),electroacupuncture or intraperitoneal injection of morphine.The ir-MEK content ofhippocampus could also increase after intra-PAG injection of SP or intraperitoncal injec-tion of morphine.The combination of intra-PAG injection of SP andelectroacupuncture caused a more marked elevation of PT and ir-MEK content of the 3brain regions than either of the two used singly could(P【0.01 ).The combined effect ofintra-PAG injection of SP and intraperitoneal injection of morphine was similar to thatof either of the two used singly(P】0.05).These facts indicate that thc analgesic effect ofSP activated by PAG was mediated through the increase of cerebral met-cnkcphalin con-tent,and there was a synergic effect between SP and elcctroacupuncturc.
基金the National Natural Science Foundation of China(No.71373219)
文摘In this article, we use the unrestricted two-regime autoregressive threshold model to test both nonlinearity and stationarity of China's real exchange rate against its Hong Kong and Macao special administrative regions(SARs). Our main finding is that China's real exchange rate is neither linear nor stationary, indicating that the purchasing power parity does not hold between China Mainland and its two SARs, which implies, to certain extent, the three economies may not meet the condition of constituting an optimal currency area.