We report the conductance and average current through a triple-quantum-dot interferometer coupled with two ferromagnetic leads using the nonequilibrium Green’s function.The results show that the interference between ...We report the conductance and average current through a triple-quantum-dot interferometer coupled with two ferromagnetic leads using the nonequilibrium Green’s function.The results show that the interference between the resonant process and the non-resonant process leads to the formation of Fano resonance.More Fano resonances can be observed by applying a time-dependent external field.As a Zeeman magnetic field is applied,the spin-up electron transport is depressed in a certain range of electron energy levels.A spin-polarized pulse device can be realized by adjusting the spin polarization parameters of ferromagnetic leads.Moreover,the I–V characteristic curves show that under the influence of Fano resonance,the spin polarization is significantly enhanced by applying a relatively large reverse bias voltage.These results strongly suggest that the spin-polarized pulse device can be potentially applied as a spin-dependent quantum device.展开更多
Human SAMHD1(h SAM)restricts lentiviruses at the reverse transcription step through its d NTP triphosphohydrolase(d NTPase)activity.Besides humans,several mammalian species such as cats and cows that carry their own l...Human SAMHD1(h SAM)restricts lentiviruses at the reverse transcription step through its d NTP triphosphohydrolase(d NTPase)activity.Besides humans,several mammalian species such as cats and cows that carry their own lentiviruses also express SAMHD1.However,the intracellular distribution of feline and bovine SAMHD1(f SAM and b SAM)and its significance in their lentiviral restriction function is not known.Here,we demonstrated that f SAM and b SAM were both predominantly localized to the nucleus and nuclear localization signal(11KRPR14)-deleted f SAM and b SAM relocalized to the cytoplasm.Both cytoplasmic f SAM and b SAM retained the antiviral function against different lentiviruses and cytoplasmic f SAM could restrict Vpx-encoding SIV and HIV-2 more efficiently than its wild-type(WT)protein as cytoplasmic h SAM.Further investigation revealed that cytoplasmic f SAM was resistant to Vpx-induced degradation like cytoplasmic h SAM,while cytoplasmic b SAM was not,but they all demonstrated the same in vitro d NTPase activity and all could interact with Vpx as their WT proteins,indicating that cytoplasmic h SAM and f SAM can suppress more SIV and HIV-2 by being less sensitive to Vpx-mediated degradation.Our results suggested that f SAM-and b SAM-mediated lentiviral restriction does not require their nuclear localization and that f SAM shares more common features with h SAM.These findings may provide insights for the establishment of alternative animal models to study SAMHD1 in vivo.展开更多
基金the National Natural Science Foundation of China(Grant No.11447132)the“Chunhui Plan”Cooperative Scientific Research Project of China(Grant No.6101020101)the Science and Technology Research Program of Chongqing Education Commission of China(Grant No.KJQN201801402)。
文摘We report the conductance and average current through a triple-quantum-dot interferometer coupled with two ferromagnetic leads using the nonequilibrium Green’s function.The results show that the interference between the resonant process and the non-resonant process leads to the formation of Fano resonance.More Fano resonances can be observed by applying a time-dependent external field.As a Zeeman magnetic field is applied,the spin-up electron transport is depressed in a certain range of electron energy levels.A spin-polarized pulse device can be realized by adjusting the spin polarization parameters of ferromagnetic leads.Moreover,the I–V characteristic curves show that under the influence of Fano resonance,the spin polarization is significantly enhanced by applying a relatively large reverse bias voltage.These results strongly suggest that the spin-polarized pulse device can be potentially applied as a spin-dependent quantum device.
基金funded by the National Natural Science Foundation of China(31270807)the Key Projects in the National Science&Technology Pillar Program in the Thirteenth Five-year Plan Period(2018ZX10731101-002-003 and 2018ZX10731101-001-020)+3 种基金Program for Jilin University Science and Technology Innovative Research Team(JLUSTIRT)(2017TD05)National Postdoctoral Program for Innovative Talents(BX20180124)China Postdoctoral Science Foundation(2018M641786)Science and Technology Development Project of Jilin Province(20200901030SF)。
文摘Human SAMHD1(h SAM)restricts lentiviruses at the reverse transcription step through its d NTP triphosphohydrolase(d NTPase)activity.Besides humans,several mammalian species such as cats and cows that carry their own lentiviruses also express SAMHD1.However,the intracellular distribution of feline and bovine SAMHD1(f SAM and b SAM)and its significance in their lentiviral restriction function is not known.Here,we demonstrated that f SAM and b SAM were both predominantly localized to the nucleus and nuclear localization signal(11KRPR14)-deleted f SAM and b SAM relocalized to the cytoplasm.Both cytoplasmic f SAM and b SAM retained the antiviral function against different lentiviruses and cytoplasmic f SAM could restrict Vpx-encoding SIV and HIV-2 more efficiently than its wild-type(WT)protein as cytoplasmic h SAM.Further investigation revealed that cytoplasmic f SAM was resistant to Vpx-induced degradation like cytoplasmic h SAM,while cytoplasmic b SAM was not,but they all demonstrated the same in vitro d NTPase activity and all could interact with Vpx as their WT proteins,indicating that cytoplasmic h SAM and f SAM can suppress more SIV and HIV-2 by being less sensitive to Vpx-mediated degradation.Our results suggested that f SAM-and b SAM-mediated lentiviral restriction does not require their nuclear localization and that f SAM shares more common features with h SAM.These findings may provide insights for the establishment of alternative animal models to study SAMHD1 in vivo.
