Background:Echinococcosis is a global zoonotic parasitic disease caused by Echinococcus larvae.This disease is highly endemic in Sichuan Province,China.This study investigates the prevalence and spatial distribution c...Background:Echinococcosis is a global zoonotic parasitic disease caused by Echinococcus larvae.This disease is highly endemic in Sichuan Province,China.This study investigates the prevalence and spatial distribution characteristics of human echinococcosis at the township level in Sichuan Province,geared towards providing a future reference for the development of precise prevention and control strategies.展开更多
Background:Echinococcosis caused byEchinococcus is one of the most major infectious diseases in north-west highland of China.E.granulosus sensu strict,E.multilocularis,andE.canadensis are known to be the only three sp...Background:Echinococcosis caused byEchinococcus is one of the most major infectious diseases in north-west highland of China.E.granulosus sensu strict,E.multilocularis,andE.canadensis are known to be the only three species related to human health transmitting in the areas.To achieve targeted treatment and control of echinococcosis,the accurate identification and discrimination of the species are important.However,currently the available diagnostic approaches do not present ideal results either in accuracy or efficiency.Methods:In the study,a set of primers were designed to aim at the three human-pathogenicEchinococcus species in China.The one-step multiplex PCR assay was developed and evaluated for the specificity and sensitivity.A total of 73parasitic lesions and 41 fecal materials obtained from human and various animals collected in the clinic and the field were tested to assess the applicability of this method.Results:The multiplex PCR effectively detected the individual DNA from the targeted species and their random mixtures generating with distinguishable expected size of products.The detection limit of the assay for each of the three species was 5 pg/μl when they were tested separately.When DNA mixtures of the targeted species containing the same concentration were used as templates,the lowest amount of DNA which can be detected was 50 pg/μl,10 pg/μl and 5 pg/μl forE.granulosus s.s.,E.multilocularis,andE.canadensis respectively.No cross-reactivity was observed when DNA from eight genetically close species was used as control templates.The multiplex PCR identifications of all samples were in line with the original sequencing results except for those infected withE.shiquicus,which showed negative signals in the developed assay.Of all the tested stool materials,16 were previously found positive forEchinococcus by visual and microscopic examination.Among these 16 samples,13 were confirmed by the multiplex PCR,and the other three tested negative.Additionally,the multiplex PCR identified another 14 positive feces from the remained 25 stool samples which absence of worms.Conclusions:The developed multiplex PCR shows advantages in fast diagnosis and large-scale epidemiological investigation,which proven to be a promising tool utilized in clinic and surveillance system.展开更多
Phase-coherent multi-tone lasers play a critical role in atomic,molecular,and optical physics.Among them,the Raman opeartion laser for manipulating atomic hyperfine qubits requires gigahertz bandwidth and low phase no...Phase-coherent multi-tone lasers play a critical role in atomic,molecular,and optical physics.Among them,the Raman opeartion laser for manipulating atomic hyperfine qubits requires gigahertz bandwidth and low phase noise to retain long-term coherence.Raman operation lasers generated by directly modulated and frequency-multipled infrared lasers are compact and stable but lack feedback control to actively suppress the phase noise,which limits their performance in practical applications.In this work,we employ a fiber electro-optical modulator driven by a voltage-controlled oscillator(VCO)to modulate a monochromatic laser and employ a second-harmonic generation process to convert it to the visible domain,where the beat note of the Raman operation laser is stabilized by controlling the output frequency of VCO with a digital phase-locked loop(PLL).The low-frequency phase noise is effectively suppressed compared to the scheme without active feedback and it reaches-80 d Bc/Hz@5 k Hz with a 20 k Hz loop bandwidth.Furthermore,this compact and robust scheme effectively reduces the system's complexity and cost,which is promising for extensive application in atomic,molecular,and optical physics.展开更多
文摘Background:Echinococcosis is a global zoonotic parasitic disease caused by Echinococcus larvae.This disease is highly endemic in Sichuan Province,China.This study investigates the prevalence and spatial distribution characteristics of human echinococcosis at the township level in Sichuan Province,geared towards providing a future reference for the development of precise prevention and control strategies.
基金the Scientific Research Project of Health and Family Planning Commission of Sichuan Province(No.17PJ440).
文摘Background:Echinococcosis caused byEchinococcus is one of the most major infectious diseases in north-west highland of China.E.granulosus sensu strict,E.multilocularis,andE.canadensis are known to be the only three species related to human health transmitting in the areas.To achieve targeted treatment and control of echinococcosis,the accurate identification and discrimination of the species are important.However,currently the available diagnostic approaches do not present ideal results either in accuracy or efficiency.Methods:In the study,a set of primers were designed to aim at the three human-pathogenicEchinococcus species in China.The one-step multiplex PCR assay was developed and evaluated for the specificity and sensitivity.A total of 73parasitic lesions and 41 fecal materials obtained from human and various animals collected in the clinic and the field were tested to assess the applicability of this method.Results:The multiplex PCR effectively detected the individual DNA from the targeted species and their random mixtures generating with distinguishable expected size of products.The detection limit of the assay for each of the three species was 5 pg/μl when they were tested separately.When DNA mixtures of the targeted species containing the same concentration were used as templates,the lowest amount of DNA which can be detected was 50 pg/μl,10 pg/μl and 5 pg/μl forE.granulosus s.s.,E.multilocularis,andE.canadensis respectively.No cross-reactivity was observed when DNA from eight genetically close species was used as control templates.The multiplex PCR identifications of all samples were in line with the original sequencing results except for those infected withE.shiquicus,which showed negative signals in the developed assay.Of all the tested stool materials,16 were previously found positive forEchinococcus by visual and microscopic examination.Among these 16 samples,13 were confirmed by the multiplex PCR,and the other three tested negative.Additionally,the multiplex PCR identified another 14 positive feces from the remained 25 stool samples which absence of worms.Conclusions:The developed multiplex PCR shows advantages in fast diagnosis and large-scale epidemiological investigation,which proven to be a promising tool utilized in clinic and surveillance system.
基金supported by the National Key Research and Development Program of China(No.2017YFA0304100)National Natural Science Foundation of China(Nos.11774335,11734015,and 12204455)+1 种基金the Key Research Program of Frontier Sciences,CAS(No.QYZDY-SSWSLH003)Innovation Program for Quantum Science and Technology(Nos.2021ZD0301604 and 2021ZD0301200)。
文摘Phase-coherent multi-tone lasers play a critical role in atomic,molecular,and optical physics.Among them,the Raman opeartion laser for manipulating atomic hyperfine qubits requires gigahertz bandwidth and low phase noise to retain long-term coherence.Raman operation lasers generated by directly modulated and frequency-multipled infrared lasers are compact and stable but lack feedback control to actively suppress the phase noise,which limits their performance in practical applications.In this work,we employ a fiber electro-optical modulator driven by a voltage-controlled oscillator(VCO)to modulate a monochromatic laser and employ a second-harmonic generation process to convert it to the visible domain,where the beat note of the Raman operation laser is stabilized by controlling the output frequency of VCO with a digital phase-locked loop(PLL).The low-frequency phase noise is effectively suppressed compared to the scheme without active feedback and it reaches-80 d Bc/Hz@5 k Hz with a 20 k Hz loop bandwidth.Furthermore,this compact and robust scheme effectively reduces the system's complexity and cost,which is promising for extensive application in atomic,molecular,and optical physics.
