As a microwave generator, spin transfer nano-oscillator(STNO) based on skyrmion promises to become one of the next-generation spintronic devices. However, there still exist a few limitations to the practical applicati...As a microwave generator, spin transfer nano-oscillator(STNO) based on skyrmion promises to become one of the next-generation spintronic devices. However, there still exist a few limitations to the practical applications. In this paper, we propose a new STNO based on synthetic antiferromagnetic(SAF) skyrmion pair assisted by a perpendicular fixed magnetic field. It is found that the oscillation frequency of this kind of STNO can reach up to 5.0 GHz, and the multiple oscillation peak with higher frequency can be realized under a fixed out-of-plane magnetic field. Further investigation shows that the skyrmion stability is improved by bilayer antiferromagnetic coupling, which guarantees the stability process of skyrmion under higher spin-polarized current density. Our results provide the alternative possibilities for designing new skyrmionbased STNO to further improve the oscillation frequency, and realize the output of multiple frequency microwave signal.展开更多
Objective:To analyze the evaluation value of coronary CT angiography for coronary plaque features and its correlation with platelet function and serum biochemical indexes.Methods:A total of 450 patients with coronary ...Objective:To analyze the evaluation value of coronary CT angiography for coronary plaque features and its correlation with platelet function and serum biochemical indexes.Methods:A total of 450 patients with coronary heart disease were divided into calcified plaque group (CT value≥130HU) (n=117), soft plaque group (CT value≤60HU) (n=150) and mixed plaque group (CT value 60-130HU) (n=183) by coronary CT angiography (CTA), and 100 healthy subjects who received physical examination in our hospital during the same period were selected as control group. Differences in platelet function and serum biochemical indexes were compared among four groups of patients, and the judgment value of atheromatous plaque CT value from CTA for the severity of coronary heart disease was analyzed.Results: Platelet function parameters MPV, TEG-MA, P-selectin, PDGF-BB and vWF levels in peripheral blood of soft plaque group were higher than those of the other three groups;inflammatory factors CRP, IL-6, IL-12, IL-18 and IL-23 content in serum were higher than those of the other three groups;chemokines MCP-1, CXCL16, Fractalkine and RANTES content in serum were higher than those of the other three groups;adipocytokines Leptin and RBP4 content in serum were higher than those of the other three groups while SFRP5 content was lower than those of the other three groups. Atheromatous plaque CT value in patients with coronary heart disease was directly correlated with platelet function and the content of serum biochemical indexes. Conclusions: Coronary CTA can accurately assess coronary atheromatous plaque features, and can also be a reliable noninvasive method to judge coronary heart disease severity, treatment prognosis and so on.展开更多
In this work,the single-chain elasticity of polyformaldehyde(POM)is studied,for the first time,by employing atomic force microscopy(AFM)-based single molecule force spectroscopy(SMFS).We find that the single-chain ela...In this work,the single-chain elasticity of polyformaldehyde(POM)is studied,for the first time,by employing atomic force microscopy(AFM)-based single molecule force spectroscopy(SMFS).We find that the single-chain elasticity of POM in a nonpolar organic solvent(nonane)can be described well by a theoretical model(QM-FRC model),when the rotating unit length is 0.144 nm(C―O bond length).After comparison,POM is more flexible than polystyrene(a typical polymer with C―C backbone)at the single-chain level,which is reasonable since the C―O bond has a lower rotation barrier than C―C bond.This result indicates that the flexibility of a polymer chain can be tuned by the C―O bond proportion in backbone,which casts new light on the rational design of new synthetic polymers in the future.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12074158, 12174166, 12104197, and 12104124)the Natural Science Foundation of Hebei Province, China (Grant No. A2021201008)。
文摘As a microwave generator, spin transfer nano-oscillator(STNO) based on skyrmion promises to become one of the next-generation spintronic devices. However, there still exist a few limitations to the practical applications. In this paper, we propose a new STNO based on synthetic antiferromagnetic(SAF) skyrmion pair assisted by a perpendicular fixed magnetic field. It is found that the oscillation frequency of this kind of STNO can reach up to 5.0 GHz, and the multiple oscillation peak with higher frequency can be realized under a fixed out-of-plane magnetic field. Further investigation shows that the skyrmion stability is improved by bilayer antiferromagnetic coupling, which guarantees the stability process of skyrmion under higher spin-polarized current density. Our results provide the alternative possibilities for designing new skyrmionbased STNO to further improve the oscillation frequency, and realize the output of multiple frequency microwave signal.
基金Natural Science Foundation of Science and Technology Commitee of Liaoning Province No:972254.
文摘Objective:To analyze the evaluation value of coronary CT angiography for coronary plaque features and its correlation with platelet function and serum biochemical indexes.Methods:A total of 450 patients with coronary heart disease were divided into calcified plaque group (CT value≥130HU) (n=117), soft plaque group (CT value≤60HU) (n=150) and mixed plaque group (CT value 60-130HU) (n=183) by coronary CT angiography (CTA), and 100 healthy subjects who received physical examination in our hospital during the same period were selected as control group. Differences in platelet function and serum biochemical indexes were compared among four groups of patients, and the judgment value of atheromatous plaque CT value from CTA for the severity of coronary heart disease was analyzed.Results: Platelet function parameters MPV, TEG-MA, P-selectin, PDGF-BB and vWF levels in peripheral blood of soft plaque group were higher than those of the other three groups;inflammatory factors CRP, IL-6, IL-12, IL-18 and IL-23 content in serum were higher than those of the other three groups;chemokines MCP-1, CXCL16, Fractalkine and RANTES content in serum were higher than those of the other three groups;adipocytokines Leptin and RBP4 content in serum were higher than those of the other three groups while SFRP5 content was lower than those of the other three groups. Atheromatous plaque CT value in patients with coronary heart disease was directly correlated with platelet function and the content of serum biochemical indexes. Conclusions: Coronary CTA can accurately assess coronary atheromatous plaque features, and can also be a reliable noninvasive method to judge coronary heart disease severity, treatment prognosis and so on.
基金the National Natural Science Foundation of China(No.21774102).
文摘In this work,the single-chain elasticity of polyformaldehyde(POM)is studied,for the first time,by employing atomic force microscopy(AFM)-based single molecule force spectroscopy(SMFS).We find that the single-chain elasticity of POM in a nonpolar organic solvent(nonane)can be described well by a theoretical model(QM-FRC model),when the rotating unit length is 0.144 nm(C―O bond length).After comparison,POM is more flexible than polystyrene(a typical polymer with C―C backbone)at the single-chain level,which is reasonable since the C―O bond has a lower rotation barrier than C―C bond.This result indicates that the flexibility of a polymer chain can be tuned by the C―O bond proportion in backbone,which casts new light on the rational design of new synthetic polymers in the future.
