The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This stu...The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.展开更多
Cryospheric meltwater is an important runoff component and it profoundly influences changes in water resources in the Tibetan Plateau.Significant changes in runoff components occur in the three-river headwater region(...Cryospheric meltwater is an important runoff component and it profoundly influences changes in water resources in the Tibetan Plateau.Significant changes in runoff components occur in the three-river headwater region(TRHR),which is an important part of“Chinese Water Tower”due to climate warming.However,these effects remain unclear owing to the sparse and uneven distribution of monitoring sites and limited field investigations.Quantifying the contribution of cryospheric meltwater to outlet runoff is a key scientific question that needs to be addressed.In this study,we analyzed 907 precipitation,river water,ground ice,supra-permafrost water,and glacier snow meltwater samples collected from October 2019 to September 2020 in the TRHR.The following results were obtained:(1)There was significant spatio-temporal variation in stable isotopes in different waters;(2)The seasonal trends of stable isotopes for different waters,the relationship between each water body and the local meteoric water line(LWML)confirmed that river water was mainly recharged by precipitation,supra-permafrost water,and glacier snow meltwater;(3)Precipitation,supra-permafrost water,and glacier snow meltwater accounted for 52%,39%,and 9%of river water,respectively,during the ablation period according to the end-member mixing analysis(EMMA);(4)In terms of future runoff components,there will be many challenges due to increasing precipitation and evaporation,decreasing snow cover,glacier retreat,and permafrost degradation.Therefore,it is crucial to establish the“star-machine-ground”observation networks,forecast extreme precipitation and hydrological events,build the“TRHE on the Cloud”platform,and implement systematic hydraulic engineering projects to support the management and utilization of water resources in the TRHR.The findings of environmental isotope analysis provide insights into water resources as well as scientific basis for rational use of water resources in the TRHR.展开更多
Recent studies on the inhibition of tumor growth by Se-containing polysaccharide were reviewed.Meanwhile,the possible molecular mechanisms of the inhibition of tumor cell growth through antioxidation,induction of tumo...Recent studies on the inhibition of tumor growth by Se-containing polysaccharide were reviewed.Meanwhile,the possible molecular mechanisms of the inhibition of tumor cell growth through antioxidation,induction of tumor cell apoptosis,blockade of cell cycle,and enhancement of immunity by Se-containing polysaccharide were proposed.In the end,the potential application of Se-containing polysaccharide in the prevention and treatment of tumor was elucidated.展开更多
文摘The publication of ISO 15686-5 is significant for studies related to the life-cycle costs of buildings. Among the many economic evaluation methods, the NPV method is recommended for use by this standard. This study explains the concept and method of PV, and then provides an explanation of the concept and method of NPV, and points out the limitations in the practical application of the method.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0405)National Nature Science Foundation of China(42077187)+2 种基金Chinese Academy of Sciences Young Crossover Team Project(JCTD-2022-18)the National Key Research and Development Program of China(2020YFA0607702)the"Western Light"-Key Laboratory Cooperative Research Cross-Team Project of Chinese Academy of Sciences,Innovative Groups in Gansu Province(20JR10RA038).
文摘Cryospheric meltwater is an important runoff component and it profoundly influences changes in water resources in the Tibetan Plateau.Significant changes in runoff components occur in the three-river headwater region(TRHR),which is an important part of“Chinese Water Tower”due to climate warming.However,these effects remain unclear owing to the sparse and uneven distribution of monitoring sites and limited field investigations.Quantifying the contribution of cryospheric meltwater to outlet runoff is a key scientific question that needs to be addressed.In this study,we analyzed 907 precipitation,river water,ground ice,supra-permafrost water,and glacier snow meltwater samples collected from October 2019 to September 2020 in the TRHR.The following results were obtained:(1)There was significant spatio-temporal variation in stable isotopes in different waters;(2)The seasonal trends of stable isotopes for different waters,the relationship between each water body and the local meteoric water line(LWML)confirmed that river water was mainly recharged by precipitation,supra-permafrost water,and glacier snow meltwater;(3)Precipitation,supra-permafrost water,and glacier snow meltwater accounted for 52%,39%,and 9%of river water,respectively,during the ablation period according to the end-member mixing analysis(EMMA);(4)In terms of future runoff components,there will be many challenges due to increasing precipitation and evaporation,decreasing snow cover,glacier retreat,and permafrost degradation.Therefore,it is crucial to establish the“star-machine-ground”observation networks,forecast extreme precipitation and hydrological events,build the“TRHE on the Cloud”platform,and implement systematic hydraulic engineering projects to support the management and utilization of water resources in the TRHR.The findings of environmental isotope analysis provide insights into water resources as well as scientific basis for rational use of water resources in the TRHR.
基金supported by the National Natural Science Foundation of China(Grant No.30770276).
文摘Recent studies on the inhibition of tumor growth by Se-containing polysaccharide were reviewed.Meanwhile,the possible molecular mechanisms of the inhibition of tumor cell growth through antioxidation,induction of tumor cell apoptosis,blockade of cell cycle,and enhancement of immunity by Se-containing polysaccharide were proposed.In the end,the potential application of Se-containing polysaccharide in the prevention and treatment of tumor was elucidated.