Objective This work examines the impact of external electric fields at terahertz(THz)frequencies on doublestranded deoxyribonucleic acid(dsDNA)systems adsorbed on Au(111)surfaces in aqueous environments.Methods The in...Objective This work examines the impact of external electric fields at terahertz(THz)frequencies on doublestranded deoxyribonucleic acid(dsDNA)systems adsorbed on Au(111)surfaces in aqueous environments.Methods The investigation utilizes a molecular dynamics(MD)approach at the atomic level and vibrational dynamics calculations using the GolDNA-Amber force field.Results The results reveal that the sugar-phosphate backbone of the DNA exhibits reduced adherence to the gold surface,while the side chains display a stronger affinity.When subjecting the hydrated DNA strands to an electric field with frequencies up to 10 THz,peak intensities of vibrational dynamic density(VDoS)are observed at five different frequencies.Moreover,the strong electric field causes hydrogen bonds in the DNA within the slit to break.The sensitivity to the electric field is particularly pronounced at 8.8 THz and 9.6 THz,with different vibrational modes observed at varying electric field strengths.Conclusion These findings contribute to an enhanced understanding of the molecular organization of gold-plated charged biological interfaces.展开更多
低频电场解冻(low-frequency electric field thawing,LFEFT)与常温解冻(room temperature thawing,RTT)会导致牛肉pH值、颜色、总挥发性盐基氮(total volatile base nitrogen,TVB-N)含量、质构特性和持水力等方面显著不同,从分子水平解...低频电场解冻(low-frequency electric field thawing,LFEFT)与常温解冻(room temperature thawing,RTT)会导致牛肉pH值、颜色、总挥发性盐基氮(total volatile base nitrogen,TVB-N)含量、质构特性和持水力等方面显著不同,从分子水平解析LFEFT对牛肉品质影响的可能机制,采用蛋白质组学技术对2种解冻方式牛肉进行分析。结果表明:LFEFT组与RTT组之间有551个差异丰度蛋白(differentially abundant proteins,DAPs),其中14种DAPs与牛肉品质特性(pH值、色泽、TVB-N含量、质构和持水力)呈显著相关;生物信息学分析表明,DAPs主要参与蛋白结合、代谢酶和蛋白质周转等生物功能。LFEFT既可以提高生产效率,又保证了牛肉品质。展开更多
生物鲁棒性是生物系统抵抗外界扰动或内部参数摄动引起系统行为变化的一种能力。电磁场是一种外界物理因素,可以对生物体产生影响。为了建立一种电磁场扰动下生物系统稳定鲁棒性的研究方法,以Lyapunov理论为基础,用电磁场细胞暴露系统...生物鲁棒性是生物系统抵抗外界扰动或内部参数摄动引起系统行为变化的一种能力。电磁场是一种外界物理因素,可以对生物体产生影响。为了建立一种电磁场扰动下生物系统稳定鲁棒性的研究方法,以Lyapunov理论为基础,用电磁场细胞暴露系统实时记录了在磁感应强度B为0、0.09、0.38、0.76、7.33、14.78 m T的电磁场暴露下细胞内活性氧自由基（ROS）和钙离子（Ca2＋）的含量,分析了电磁场扰动前的细胞状态稳态点和稳定域,以及电磁场扰动后的状态转移和稳定鲁棒域。结果表明：（1）细胞无扰时ROS的稳态点是46.157~120.913,Ca2＋的稳态点是25.430~55.686,ROS的稳定域半径是1.688~10.278,Ca2＋的稳定域半径是2.782~13.345;（2）B〈7.33 m T的电磁场扰动没有提高胞内ROS含量,B为14.78 m T的电磁场扰动可阶跃性提高胞内ROS含量,B为0和0.09 m T的电磁场扰动没有提高胞内Ca2＋含量,B为0.38 m T的电磁场扰动可持续性提高胞内Ca2＋含量。结论是：（1）无电磁场扰动时,细胞内ROS和Ca2＋状态可以保持稳定;（2）电磁场扰动在较高水平（如B为14.78 m T）时,才能改变细胞内ROS和Ca2＋的状态;（3）细胞的鲁棒域与电磁场的磁感应强度无关。展开更多
基金supported by a grant from National Defense Science and Technology Innovation Special Zone of China(02-ZT-008).
文摘Objective This work examines the impact of external electric fields at terahertz(THz)frequencies on doublestranded deoxyribonucleic acid(dsDNA)systems adsorbed on Au(111)surfaces in aqueous environments.Methods The investigation utilizes a molecular dynamics(MD)approach at the atomic level and vibrational dynamics calculations using the GolDNA-Amber force field.Results The results reveal that the sugar-phosphate backbone of the DNA exhibits reduced adherence to the gold surface,while the side chains display a stronger affinity.When subjecting the hydrated DNA strands to an electric field with frequencies up to 10 THz,peak intensities of vibrational dynamic density(VDoS)are observed at five different frequencies.Moreover,the strong electric field causes hydrogen bonds in the DNA within the slit to break.The sensitivity to the electric field is particularly pronounced at 8.8 THz and 9.6 THz,with different vibrational modes observed at varying electric field strengths.Conclusion These findings contribute to an enhanced understanding of the molecular organization of gold-plated charged biological interfaces.
文摘低频电场解冻(low-frequency electric field thawing,LFEFT)与常温解冻(room temperature thawing,RTT)会导致牛肉pH值、颜色、总挥发性盐基氮(total volatile base nitrogen,TVB-N)含量、质构特性和持水力等方面显著不同,从分子水平解析LFEFT对牛肉品质影响的可能机制,采用蛋白质组学技术对2种解冻方式牛肉进行分析。结果表明:LFEFT组与RTT组之间有551个差异丰度蛋白(differentially abundant proteins,DAPs),其中14种DAPs与牛肉品质特性(pH值、色泽、TVB-N含量、质构和持水力)呈显著相关;生物信息学分析表明,DAPs主要参与蛋白结合、代谢酶和蛋白质周转等生物功能。LFEFT既可以提高生产效率,又保证了牛肉品质。
文摘生物鲁棒性是生物系统抵抗外界扰动或内部参数摄动引起系统行为变化的一种能力。电磁场是一种外界物理因素,可以对生物体产生影响。为了建立一种电磁场扰动下生物系统稳定鲁棒性的研究方法,以Lyapunov理论为基础,用电磁场细胞暴露系统实时记录了在磁感应强度B为0、0.09、0.38、0.76、7.33、14.78 m T的电磁场暴露下细胞内活性氧自由基（ROS）和钙离子（Ca2＋）的含量,分析了电磁场扰动前的细胞状态稳态点和稳定域,以及电磁场扰动后的状态转移和稳定鲁棒域。结果表明：（1）细胞无扰时ROS的稳态点是46.157~120.913,Ca2＋的稳态点是25.430~55.686,ROS的稳定域半径是1.688~10.278,Ca2＋的稳定域半径是2.782~13.345;（2）B〈7.33 m T的电磁场扰动没有提高胞内ROS含量,B为14.78 m T的电磁场扰动可阶跃性提高胞内ROS含量,B为0和0.09 m T的电磁场扰动没有提高胞内Ca2＋含量,B为0.38 m T的电磁场扰动可持续性提高胞内Ca2＋含量。结论是：（1）无电磁场扰动时,细胞内ROS和Ca2＋状态可以保持稳定;（2）电磁场扰动在较高水平（如B为14.78 m T）时,才能改变细胞内ROS和Ca2＋的状态;（3）细胞的鲁棒域与电磁场的磁感应强度无关。
