NbTiN thin films are good candidates for applications including single-photon detector, kinetic inductance detector, hot electron bolometer, and superconducting quantum computing circuits because of their favorable ch...NbTiN thin films are good candidates for applications including single-photon detector, kinetic inductance detector, hot electron bolometer, and superconducting quantum computing circuits because of their favorable characteristics,such as good superconducting properties and easy fabrication.In this work, we systematically investigated the growth of high-quality NbTiN films with different thicknesses on Si substrates by reactive DC-magnetron sputtering method.After optimizing the growth conditions, such as the gas pressure, Ar/N2 mixture ratio, and sputtering power, we obtained films with excellent superconducting properties.A high superconducting transition temperature of 15.5 K with narrow transition width of 0.03 K was obtained in a film of 300 nm thickness with surface roughness of less than 0.2 nm.In an ultra-thin film of 5 nm thick, we still obtained a transition temperature of 7.6 K.In addition, rapid thermal annealing(RTA) in atmosphere of nitrogen or nitrogen and hydrogen mixture was studied to improve the film quality.The results showed that Tc and crystal size of the NbTiN films were remarkably increased by RTA.For ultrathin films, the annealing in N2/H2 mixture had better effect than that in pure N2.The Tc of 10 nm films improved from 9.6 K to 10.3 K after RTA in N2/H2 mixture at 450℃.展开更多
In this study,we aimed to assess the effect of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection on semenparameters.The study comprised 110 sperm volunteers who self-reported SARS-CoV-2 infection fr...In this study,we aimed to assess the effect of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection on semenparameters.The study comprised 110 sperm volunteers who self-reported SARS-CoV-2 infection from the Human Sperm Bank ofthe Center for Reproductive Medicine,Shandong University(Jinan,China).The volunteers had normal sperm concentration beforeinfection.Each volunteer provided semen samples before and after infection.We selected 90 days after infection as the cutoff point.Semen parameters within 90 days after infection of 109 volunteers(group A)were compared with semen parameters before infection.Moreover,semen parameters on or after 90 days after infection of 36 volunteers(group B)were compared with semen parameters beforeinfection.Furthermore,based on whether the volunteers had completed the three-dose SARS-CoV-2 vaccination booster,volunteersin group A and B were further divided into two subgroups separately.Semen parameters were compared before and after infection ineach subgroup.Our results showed that in this cohort population,the semen quality in volunteers with normal sperm concentrationsbefore infection decreased after SARS-CoV-2 infection within 90 days,while the semen quality returned to preinfection levels after 90days.The completion of a three-dose SARS-CoV-2 vaccination booster may exert a protective effect on semen quality after infection.展开更多
Melanization is an important innate immune defense mechanism of insects,which can kill invading pathogens.Most pathogens,for their survival and reproduction,inhibit the melanization of the host.Interestingly,our resul...Melanization is an important innate immune defense mechanism of insects,which can kill invading pathogens.Most pathogens,for their survival and reproduction,inhibit the melanization of the host.Interestingly,our results suggested that after infection with Heliothis virescens ascovirus 3h(HvAV-3h),the speed of melanization in infected Spodoptera exigiia larval hemolymph was accelerated and that the phenoloxidase(PO)activity of hemolymph in larvae infected with HvAV-3h increased significantly(1.20-fold at 96 hpi,1.52-fold at 120 hpi,1.23-fold at 144 hpi,1.12-fold at 168 hpi).The transcription level of the gene encoding S.exigua prophenoloxidase-1(SePPO-1 gene)was upregulated dramatically in the fat body during the middle stage of infection.In addition,when melanization was inhibited or promoted,the replication of HvAV-3h was inhibited or promoted,respectively.In conclusion,infection with HvAV-3h can markedly induce melanization in the middle stage of infection,and melanization is helpful for HvAV-3h viral replication.展开更多
基金Project supported by the Chinese Academy of Sciences Strategic Priority Research Program B(Grant No.XDB07010300)the National Natural Science Foundation of China(Grant No.11674376)
文摘NbTiN thin films are good candidates for applications including single-photon detector, kinetic inductance detector, hot electron bolometer, and superconducting quantum computing circuits because of their favorable characteristics,such as good superconducting properties and easy fabrication.In this work, we systematically investigated the growth of high-quality NbTiN films with different thicknesses on Si substrates by reactive DC-magnetron sputtering method.After optimizing the growth conditions, such as the gas pressure, Ar/N2 mixture ratio, and sputtering power, we obtained films with excellent superconducting properties.A high superconducting transition temperature of 15.5 K with narrow transition width of 0.03 K was obtained in a film of 300 nm thickness with surface roughness of less than 0.2 nm.In an ultra-thin film of 5 nm thick, we still obtained a transition temperature of 7.6 K.In addition, rapid thermal annealing(RTA) in atmosphere of nitrogen or nitrogen and hydrogen mixture was studied to improve the film quality.The results showed that Tc and crystal size of the NbTiN films were remarkably increased by RTA.For ultrathin films, the annealing in N2/H2 mixture had better effect than that in pure N2.The Tc of 10 nm films improved from 9.6 K to 10.3 K after RTA in N2/H2 mixture at 450℃.
基金supported by the National Key Research and Development Program of China(No.2022YFC2703200 and No.2021YFC2700600).
文摘In this study,we aimed to assess the effect of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection on semenparameters.The study comprised 110 sperm volunteers who self-reported SARS-CoV-2 infection from the Human Sperm Bank ofthe Center for Reproductive Medicine,Shandong University(Jinan,China).The volunteers had normal sperm concentration beforeinfection.Each volunteer provided semen samples before and after infection.We selected 90 days after infection as the cutoff point.Semen parameters within 90 days after infection of 109 volunteers(group A)were compared with semen parameters before infection.Moreover,semen parameters on or after 90 days after infection of 36 volunteers(group B)were compared with semen parameters beforeinfection.Furthermore,based on whether the volunteers had completed the three-dose SARS-CoV-2 vaccination booster,volunteersin group A and B were further divided into two subgroups separately.Semen parameters were compared before and after infection ineach subgroup.Our results showed that in this cohort population,the semen quality in volunteers with normal sperm concentrationsbefore infection decreased after SARS-CoV-2 infection within 90 days,while the semen quality returned to preinfection levels after 90days.The completion of a three-dose SARS-CoV-2 vaccination booster may exert a protective effect on semen quality after infection.
基金We would like to thank the American Journal Experts teamfor editing and revising the English language.This work was supported by the National Natural Science Foundation of China(31872027)Changsha Science and Technology Project(kq 1901033),and Double first-class construction project of Hunan Agricultural University.
文摘Melanization is an important innate immune defense mechanism of insects,which can kill invading pathogens.Most pathogens,for their survival and reproduction,inhibit the melanization of the host.Interestingly,our results suggested that after infection with Heliothis virescens ascovirus 3h(HvAV-3h),the speed of melanization in infected Spodoptera exigiia larval hemolymph was accelerated and that the phenoloxidase(PO)activity of hemolymph in larvae infected with HvAV-3h increased significantly(1.20-fold at 96 hpi,1.52-fold at 120 hpi,1.23-fold at 144 hpi,1.12-fold at 168 hpi).The transcription level of the gene encoding S.exigua prophenoloxidase-1(SePPO-1 gene)was upregulated dramatically in the fat body during the middle stage of infection.In addition,when melanization was inhibited or promoted,the replication of HvAV-3h was inhibited or promoted,respectively.In conclusion,infection with HvAV-3h can markedly induce melanization in the middle stage of infection,and melanization is helpful for HvAV-3h viral replication.
