Terminal deoxynucleotidyl transferase(Td T) has been characterized as template-independent polymerase using single-stranded DNA(ss DNA) as primers to generate random oligonucleotides. However, the extension performanc...Terminal deoxynucleotidyl transferase(Td T) has been characterized as template-independent polymerase using single-stranded DNA(ss DNA) as primers to generate random oligonucleotides. However, the extension performance of Td T to single-stranded RNA(ss RNA) is vague. By systematically comparing and contrasting the performance of Td T-catalyzed ss DNA and ss RNA extension, it is indicated that the catalytic efficiency of ss RNA as primers was about 3 times lower than ss DNA as primers. Collectively, it is believed that understanding the catalytic performance of Td T will help to design the strategy to synthesize chimeric DNA on 3-OH of ss RNA, which becomes invaluable.展开更多
Very high cycle fatigue behaviors of two bainite/martensite dual-phase steels were investigated.One of the steels was cyclic rapid heat treated and its microstructures were refined. Fatigue strength of the steel is 22...Very high cycle fatigue behaviors of two bainite/martensite dual-phase steels were investigated.One of the steels was cyclic rapid heat treated and its microstructures were refined. Fatigue strength of the steel is 225 MPa higher than that without refining.Observation of fracture surfaces show that the fatigue cracks initiate at bainites for non-refined steel and at non-metallic inclusions for the refined steel.The size of inclusions is much smaller than that of bainites which results in the improvement of fatigue strength.展开更多
To the Editor:Recent single subcortical infarction(RSSI),formerly known as lacunar stroke,is a neurological syndrome that occurs when a small perforating artery in the brain becomes blocked,resulting in ischemia and n...To the Editor:Recent single subcortical infarction(RSSI),formerly known as lacunar stroke,is a neurological syndrome that occurs when a small perforating artery in the brain becomes blocked,resulting in ischemia and neurological impairment.[1]Radiological indicators of cerebral small vessel disease(SVD),such as lacunes and white matter hyperintensity(WMH),have gained increasing attention because of their role in cognitive impairment and dementia.[1]The correlation among radiological indicators enables the investigation of their impact on both structural and functional damage to the brain.展开更多
Energy harvesting through periodic snap-through of a buckled sheet has recently gained considerable attention because of its potential applications in energy harvesting in low incoming flow.Although the snapping dynam...Energy harvesting through periodic snap-through of a buckled sheet has recently gained considerable attention because of its potential applications in energy harvesting in low incoming flow.Although the snapping dynamics of uniform buckled sheets has been extensively studied,the present work focuses on the energy harvesting and dynamics of a nonuniform snapping sheet with both of its ends clamped in a channel flow.The analysis reveals that the sheet undergoes periodic snap-through oscillations,with its rear half consistently serving as the main contributor to effective energy harvesting,and the potential energy contributing significantly more than the kinetic energy.Varying the stiffness differenceΔEI^(*)shows that increasing the stiffness of the rear part and decreasing that of the fore part shifts the deformation wave toward upstream and enhances the snapping amplitude of the fore part,optimizing energy extraction.At a length compression ratioΔL^(*)=0.3,the maximum potential energy is observed forΔEI^(*)=1,and the total energy peaks atΔEI^(*)=2.The study also identifies an optimalΔL^(*)=0.4that maximizes both total and potential energies,and triples the potential energy in comparison withΔL^(*)=0.1.However,the enhancement of nonuniformity disappears atΔL^(*)>0.3 for the total energy andΔL^(*)>0.2 for the potential energy.These findings provide insights to aid optimization of the design and performance of snapping sheet energy harvesters.展开更多
基金supported by the National Natural Science Foundation of China (NSFC, Nos. 21927814 and 21772143 to J.Y. Zhang)the National Science Foundation of Tianjin (Nos. 20YDTPJC00090, 19ZXDBSY00070 and 20YFZCSY00990 to X.Q. Gong)。
文摘Terminal deoxynucleotidyl transferase(Td T) has been characterized as template-independent polymerase using single-stranded DNA(ss DNA) as primers to generate random oligonucleotides. However, the extension performance of Td T to single-stranded RNA(ss RNA) is vague. By systematically comparing and contrasting the performance of Td T-catalyzed ss DNA and ss RNA extension, it is indicated that the catalytic efficiency of ss RNA as primers was about 3 times lower than ss DNA as primers. Collectively, it is believed that understanding the catalytic performance of Td T will help to design the strategy to synthesize chimeric DNA on 3-OH of ss RNA, which becomes invaluable.
文摘Very high cycle fatigue behaviors of two bainite/martensite dual-phase steels were investigated.One of the steels was cyclic rapid heat treated and its microstructures were refined. Fatigue strength of the steel is 225 MPa higher than that without refining.Observation of fracture surfaces show that the fatigue cracks initiate at bainites for non-refined steel and at non-metallic inclusions for the refined steel.The size of inclusions is much smaller than that of bainites which results in the improvement of fatigue strength.
基金supported by grants from the National Natural Science Foundation of China(Nos.82271328,82071320,82371322,and 82301661)China Postdoctoral Science Foundation(Nos.2022M712249 and 2023T 160447)+2 种基金Post-Doctor Research Project,West China Hospital,Sichuan University(No.2023HXBH007)National Key R&D Program of China(Nos.2023YFC2506600,2023YFC2506603)the 1·3·5 Project for Disciplines of Excellence-Clinical Research Incubation Project of West China Hospital at Sichuan University(No.2020HX FH012).
文摘To the Editor:Recent single subcortical infarction(RSSI),formerly known as lacunar stroke,is a neurological syndrome that occurs when a small perforating artery in the brain becomes blocked,resulting in ischemia and neurological impairment.[1]Radiological indicators of cerebral small vessel disease(SVD),such as lacunes and white matter hyperintensity(WMH),have gained increasing attention because of their role in cognitive impairment and dementia.[1]The correlation among radiological indicators enables the investigation of their impact on both structural and functional damage to the brain.
文摘Energy harvesting through periodic snap-through of a buckled sheet has recently gained considerable attention because of its potential applications in energy harvesting in low incoming flow.Although the snapping dynamics of uniform buckled sheets has been extensively studied,the present work focuses on the energy harvesting and dynamics of a nonuniform snapping sheet with both of its ends clamped in a channel flow.The analysis reveals that the sheet undergoes periodic snap-through oscillations,with its rear half consistently serving as the main contributor to effective energy harvesting,and the potential energy contributing significantly more than the kinetic energy.Varying the stiffness differenceΔEI^(*)shows that increasing the stiffness of the rear part and decreasing that of the fore part shifts the deformation wave toward upstream and enhances the snapping amplitude of the fore part,optimizing energy extraction.At a length compression ratioΔL^(*)=0.3,the maximum potential energy is observed forΔEI^(*)=1,and the total energy peaks atΔEI^(*)=2.The study also identifies an optimalΔL^(*)=0.4that maximizes both total and potential energies,and triples the potential energy in comparison withΔL^(*)=0.1.However,the enhancement of nonuniformity disappears atΔL^(*)>0.3 for the total energy andΔL^(*)>0.2 for the potential energy.These findings provide insights to aid optimization of the design and performance of snapping sheet energy harvesters.
