Socioeconomic development induced nonpoint source(NPS)pollution has aroused an increasing concern,however,most of the previous studies were concentrated on the impacts of environmental determinants.Here,total nitrogen...Socioeconomic development induced nonpoint source(NPS)pollution has aroused an increasing concern,however,most of the previous studies were concentrated on the impacts of environmental determinants.Here,total nitrogen(TN)and total phosphorus(TP)concentrations from 13 sampling sites were collected biweekly from January 2018 to October 2021,and 26 potential factors including environmental and socioeconomic were considered in the Wangjiaqiao watershed of the Three Gorges Reservoir Area,China.Impacts of these factors on TN and TP were evaluated by partial least squares regression(PLSR)model.It showed that average TN and TP concentrations in wet seasons(TN,14.68 mg L^(-1):TP,0.113 mg L^(-1))were higher than that in dry seasons(TN,11.73 mg L^(-1);TP,0.087 mg L^(-1)).Additionally,the TN concentrations were greater in downstream than upstream,however,the highest TP concentrations were found in the middle of the watershed.The optimal PLSR model explained 69.6%,73.1%and 66.1%of the variance in TN concentration,as well as 65.7%,79.5%and 67.4%of the variance in TP concentration during the annual,dry and wet seasons,respectively.Moreover,TN was primarily influenced by topographic wetness index,planting structure,interspersion and juxtaposition index,orchard proportion,nitrogen fertilization,per capita income,and catchment area,whereas TP was mainly controlled by slope gradient,topographic wetness index,hypsometric integral,interspersion and juxtaposition index,and population density.Collectively,environmental factors had greater impacts on the TN and TP concentrations than socioeconomic factors.Raising farmers'awareness of the hazards of NPS pollution is beneficial to watershed NPS pollution control.展开更多
Human apolipoprotein E4(APOE4)is an important risk factor for late-onset Alzheimer’s disease(AD).However,little progress has been made for the detection of APOE4,and most of existing detection methods suffer from tim...Human apolipoprotein E4(APOE4)is an important risk factor for late-onset Alzheimer’s disease(AD).However,little progress has been made for the detection of APOE4,and most of existing detection methods suffer from time-consuming process and expensive instruments.This study firstly proposed a simple and sensitive electrochemical method for detection of APOE4 based on carboxyl-rich CeZnO nanoparticles.Under the optimal conditions,the fabricated immunosensor exhibited a good linear relationship ranging from 10 to 100 ng/mL with the detection limit of 1.8 ng/mL(S/N=3).The proposed electrochemical immunosensor had excellent selectivity,reproducibility and stability.Good performance was observed for sensitive determination of APOE4 in human serum sample,which provided a strong support for the detection of APOE4 and early clinical prevention of AD.展开更多
基金funded by the National Natural Science Foundation of China[grant number 42077065,U240222].
文摘Socioeconomic development induced nonpoint source(NPS)pollution has aroused an increasing concern,however,most of the previous studies were concentrated on the impacts of environmental determinants.Here,total nitrogen(TN)and total phosphorus(TP)concentrations from 13 sampling sites were collected biweekly from January 2018 to October 2021,and 26 potential factors including environmental and socioeconomic were considered in the Wangjiaqiao watershed of the Three Gorges Reservoir Area,China.Impacts of these factors on TN and TP were evaluated by partial least squares regression(PLSR)model.It showed that average TN and TP concentrations in wet seasons(TN,14.68 mg L^(-1):TP,0.113 mg L^(-1))were higher than that in dry seasons(TN,11.73 mg L^(-1);TP,0.087 mg L^(-1)).Additionally,the TN concentrations were greater in downstream than upstream,however,the highest TP concentrations were found in the middle of the watershed.The optimal PLSR model explained 69.6%,73.1%and 66.1%of the variance in TN concentration,as well as 65.7%,79.5%and 67.4%of the variance in TP concentration during the annual,dry and wet seasons,respectively.Moreover,TN was primarily influenced by topographic wetness index,planting structure,interspersion and juxtaposition index,orchard proportion,nitrogen fertilization,per capita income,and catchment area,whereas TP was mainly controlled by slope gradient,topographic wetness index,hypsometric integral,interspersion and juxtaposition index,and population density.Collectively,environmental factors had greater impacts on the TN and TP concentrations than socioeconomic factors.Raising farmers'awareness of the hazards of NPS pollution is beneficial to watershed NPS pollution control.
基金The National Youth Foundation of China(Grant No.81803487)National Natural Science Foundation(Grant No.81673392)China Postdoctoral Science Foundation(Grant No.2018M631285).
文摘Human apolipoprotein E4(APOE4)is an important risk factor for late-onset Alzheimer’s disease(AD).However,little progress has been made for the detection of APOE4,and most of existing detection methods suffer from time-consuming process and expensive instruments.This study firstly proposed a simple and sensitive electrochemical method for detection of APOE4 based on carboxyl-rich CeZnO nanoparticles.Under the optimal conditions,the fabricated immunosensor exhibited a good linear relationship ranging from 10 to 100 ng/mL with the detection limit of 1.8 ng/mL(S/N=3).The proposed electrochemical immunosensor had excellent selectivity,reproducibility and stability.Good performance was observed for sensitive determination of APOE4 in human serum sample,which provided a strong support for the detection of APOE4 and early clinical prevention of AD.
