Objective To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Methods We designed,developed,and manufactured an integrated disposab...Objective To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Methods We designed,developed,and manufactured an integrated disposable device for SARS-CoV-2 nucleic acid extraction and detection.The precision of the liquid transfer and temperature control was tested.A comparison between our device and a commercial kit for SARS-Cov-2 nucleic acid extraction was performed using real-time fluorescence reverse transcription polymerase chain reaction(RT-PCR).The entire process,from SARS-CoV-2 nucleic acid extraction to amplification,was evaluated.Results The precision of the syringe transfer volume was 19.2±1.9μL(set value was 20),32.2±1.6(set value was 30),and 57.2±3.5(set value was 60).Temperature control in the amplification tube was measured at 60.0±0.0℃(set value was 60)and 95.1±0.2℃(set value was 95)respectively.SARS-Cov-2 nucleic acid extraction yield through the device was 7.10×10^(6) copies/mL,while a commercial kit yielded 2.98×10^(6) copies/mL.The mean time to complete the entire assay,from SARS-CoV-2 nucleic acid extraction to amplification detection,was 36 min and 45 s.The detection limit for SARS-CoV-2 nucleic acid was 250 copies/mL.Conclusion The integrated disposable devices may be used for SARS-CoV-2 Point-of-Care test(POCT).展开更多
Dear Editor,Astrovirus is an enteric virus associated with sporadic diarrhea or large outbreaks of gastroenteritis（Mendez et al.,2013）.Until 2008,human astroviruses（HAst Vs）were classified into eight serotypes—HA...Dear Editor,Astrovirus is an enteric virus associated with sporadic diarrhea or large outbreaks of gastroenteritis（Mendez et al.,2013）.Until 2008,human astroviruses（HAst Vs）were classified into eight serotypes—HAstV-1 to HAstV-8—based on the reactivity of their capsid protein with type-specific antibodies.Among these serotypes,HAstV-1is the most prevalent globally.However,some divergent new astroviruses（MLB1/MLB2,VA1/VA2/VA3,展开更多
The massive scale of new-generation rural-urban migrants in China has attracted extensive scholarly attention in recent years.While previous studies on China’s rural migrant workers focus on migrants’settlement inte...The massive scale of new-generation rural-urban migrants in China has attracted extensive scholarly attention in recent years.While previous studies on China’s rural migrant workers focus on migrants’settlement intentions,migrants’family migration decision-making and the intergenerational differences between the old-generation migrants and new-generation migrants are underexplored.Based on the data of the 2017 China Migrants Dynamic Survey,this paper adopts a multilevel logistic regression approach to explore family and destination factors influencing the family migration decisions of China’s new generation of rural migrant workers.The empirical results reveal that both the migrants’family and destination attributes significantly influence their family migration decision.The demographic and socioeconomic characteristics of the family have been pivotal factors underlying the family migration decision of China’s new generation rural-urban migrants,while 16.9%of the chances are explained by between-destination differences.Self-employed migrants with housing properties in host cities,long migration duration and high-income levels are more likely to migrate with their family members.Yet,the possibility of family migration is found to be significantly and negatively correlated with the age,education level,number of children and inter-provincial mobility of the new generation of migrant workers.In addition,new-generation rural-urban migrants’family migration is more likely to be found in cities with service-oriented industry structures,better environmental quality,and higher hukou barriers which is possibly related to more job opportunities.These research findings not only complement the existing literature on China’s new generation of rural urban migrants,but also have important policy implications for reforming the hukou system and enhancing social integration of the rural-to-urban migrant population.展开更多
基金supported by National Key R&D Program of China[2021YFC2301103 and 2022YFE0202600]Shenzhen Science and Technology Program[JSGG20220606142605011].
文摘Objective To develop a highly sensitive and rapid nucleic acid detection method for the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Methods We designed,developed,and manufactured an integrated disposable device for SARS-CoV-2 nucleic acid extraction and detection.The precision of the liquid transfer and temperature control was tested.A comparison between our device and a commercial kit for SARS-Cov-2 nucleic acid extraction was performed using real-time fluorescence reverse transcription polymerase chain reaction(RT-PCR).The entire process,from SARS-CoV-2 nucleic acid extraction to amplification,was evaluated.Results The precision of the syringe transfer volume was 19.2±1.9μL(set value was 20),32.2±1.6(set value was 30),and 57.2±3.5(set value was 60).Temperature control in the amplification tube was measured at 60.0±0.0℃(set value was 60)and 95.1±0.2℃(set value was 95)respectively.SARS-Cov-2 nucleic acid extraction yield through the device was 7.10×10^(6) copies/mL,while a commercial kit yielded 2.98×10^(6) copies/mL.The mean time to complete the entire assay,from SARS-CoV-2 nucleic acid extraction to amplification detection,was 36 min and 45 s.The detection limit for SARS-CoV-2 nucleic acid was 250 copies/mL.Conclusion The integrated disposable devices may be used for SARS-CoV-2 Point-of-Care test(POCT).
基金supported by the National Nature Science Foundation of China(No.81201285)Dr.Start-up Fund of Liaoning Province(No.20141134)+2 种基金excellent talents project in colleges and universities of the Liaoning Province Foundation(No.LJQ2015067)college students of science and technology innovation fund,Liaoning medical university principal fund(No.2014D09)approved by the ethics committees of Liao Yi[2014](NO.6-20150005)
文摘Dear Editor,Astrovirus is an enteric virus associated with sporadic diarrhea or large outbreaks of gastroenteritis（Mendez et al.,2013）.Until 2008,human astroviruses（HAst Vs）were classified into eight serotypes—HAstV-1 to HAstV-8—based on the reactivity of their capsid protein with type-specific antibodies.Among these serotypes,HAstV-1is the most prevalent globally.However,some divergent new astroviruses（MLB1/MLB2,VA1/VA2/VA3,
基金supported by the National Natural Science Foundation of China(Project Number:NSFC 71403193).
文摘The massive scale of new-generation rural-urban migrants in China has attracted extensive scholarly attention in recent years.While previous studies on China’s rural migrant workers focus on migrants’settlement intentions,migrants’family migration decision-making and the intergenerational differences between the old-generation migrants and new-generation migrants are underexplored.Based on the data of the 2017 China Migrants Dynamic Survey,this paper adopts a multilevel logistic regression approach to explore family and destination factors influencing the family migration decisions of China’s new generation of rural migrant workers.The empirical results reveal that both the migrants’family and destination attributes significantly influence their family migration decision.The demographic and socioeconomic characteristics of the family have been pivotal factors underlying the family migration decision of China’s new generation rural-urban migrants,while 16.9%of the chances are explained by between-destination differences.Self-employed migrants with housing properties in host cities,long migration duration and high-income levels are more likely to migrate with their family members.Yet,the possibility of family migration is found to be significantly and negatively correlated with the age,education level,number of children and inter-provincial mobility of the new generation of migrant workers.In addition,new-generation rural-urban migrants’family migration is more likely to be found in cities with service-oriented industry structures,better environmental quality,and higher hukou barriers which is possibly related to more job opportunities.These research findings not only complement the existing literature on China’s new generation of rural urban migrants,but also have important policy implications for reforming the hukou system and enhancing social integration of the rural-to-urban migrant population.
