Ionization of atoms in counter-rotating and co-rotating bicircular laser fields is studied using the S-matrix theory in both length and velocity gauges.We show that for both the bicircular fields,ionization rates are ...Ionization of atoms in counter-rotating and co-rotating bicircular laser fields is studied using the S-matrix theory in both length and velocity gauges.We show that for both the bicircular fields,ionization rates are enhanced when the two circularly polarized lights have comparable intensities.In addition,the curves of ionization rate versus the field amplitude ratio of the two colors for counter-rotating and co-rotating fields coincide with each other in the length gauge case at the total laser intensity 5×10^14 W/cm^2,which agrees with the experimental observation.Moreover,the degree of the coincidence between the ionization rate curves of the two bicircular fields decreases with the increasing field amplitude ratio and decreasing total laser intensity.With the help of the ADK theory,the above characteristics of the ionization rate curves can be well interpreted,which is related to the transition from the tunneling to multiphoton ionization mechanism.展开更多
This paper deals with S-matrix, born first approximation, amplitude, and differential cross-section (DCS), using Volkov function and Taylor series expansion in laser field, scattering. Equation (30) copes-with DCS and...This paper deals with S-matrix, born first approximation, amplitude, and differential cross-section (DCS), using Volkov function and Taylor series expansion in laser field, scattering. Equation (30) copes-with DCS and Equation (36) deals with S-matrix, with different parameters, moreover, both equations contain real and imaginary parts. The DCS increases with increasing angle and polarizabilities, constant with dipole distance for both emission and absorption of single-photon. The DCS for both emission and absorption is responded to low incidence energy (30 eV - 60 eV) and photon energy (15 eV) while at high energy only emission and absorption are responded for DCS. The DCS between absorption and emission of a photon with angle variation, dipole distance, and atomic polarizabilities was found 1.098 a.u.<sup>2</sup> and at high incidence, energies were found 0.1 a.u.<sup>2</sup>.展开更多
研究了单个线性关系是可闭线性关系的充分必要条件;并对L0=(A B C D),其中A,B,C,D是相应Hilbert空间上的线性关系,利用C相对A的有界性与B相对D的有界性及A,D的可闭性,推出了L_(0)也是可闭线性关系;同时,对于有界线性算子S=(S_(1) S_(2) ...研究了单个线性关系是可闭线性关系的充分必要条件;并对L0=(A B C D),其中A,B,C,D是相应Hilbert空间上的线性关系,利用C相对A的有界性与B相对D的有界性及A,D的可闭性,推出了L_(0)也是可闭线性关系;同时,对于有界线性算子S=(S_(1) S_(2) S_(3) S_(4)),得到当满足一定条件时L_(0)-μS的Frobenius-Schur分解公式,并得到了当L_(0)可闭时L_(0)的表达式,最后研究了L_(0)的S-本质谱。展开更多
基金Project supported by the Key Laboratory Project of Computational Physics of National Defense Science and Technology of China(Grant No.6142A05180401)the National Key Program for S&T Research and Development of China(Grant Nos.2019YFA0307700 and 2016YFA0401100)the National Natural Science Foundation of China(Grant Nos.11847307,11425414,11504215,11774361,and 11874246).
文摘Ionization of atoms in counter-rotating and co-rotating bicircular laser fields is studied using the S-matrix theory in both length and velocity gauges.We show that for both the bicircular fields,ionization rates are enhanced when the two circularly polarized lights have comparable intensities.In addition,the curves of ionization rate versus the field amplitude ratio of the two colors for counter-rotating and co-rotating fields coincide with each other in the length gauge case at the total laser intensity 5×10^14 W/cm^2,which agrees with the experimental observation.Moreover,the degree of the coincidence between the ionization rate curves of the two bicircular fields decreases with the increasing field amplitude ratio and decreasing total laser intensity.With the help of the ADK theory,the above characteristics of the ionization rate curves can be well interpreted,which is related to the transition from the tunneling to multiphoton ionization mechanism.
文摘This paper deals with S-matrix, born first approximation, amplitude, and differential cross-section (DCS), using Volkov function and Taylor series expansion in laser field, scattering. Equation (30) copes-with DCS and Equation (36) deals with S-matrix, with different parameters, moreover, both equations contain real and imaginary parts. The DCS increases with increasing angle and polarizabilities, constant with dipole distance for both emission and absorption of single-photon. The DCS for both emission and absorption is responded to low incidence energy (30 eV - 60 eV) and photon energy (15 eV) while at high energy only emission and absorption are responded for DCS. The DCS between absorption and emission of a photon with angle variation, dipole distance, and atomic polarizabilities was found 1.098 a.u.<sup>2</sup> and at high incidence, energies were found 0.1 a.u.<sup>2</sup>.
文摘目的:阐明细丝蛋白B基因(filamin B,FLNB)第1542位异亮氨酸(Ile/I)→苏氨酸(Thr/T)突变(FLNB p.Ile1542Thr,FLNB^(I1542T))在休门氏后凸畸形(Scheuermann′s kyphosis,SK)中的机制。方法:对一个汉族SK家系进行标准化临床评估,包括脊柱X线、CT三维重建及MRI检查。通过全外显子测序与Sanger测序筛选并验证致病性变异,依据美国医学遗传学与基因组学学会(American College of Medical Genetics and Genomics,ACMG)指南进行致病性评估。采用CRISPR-Cas9技术构建携带FLNB^(I1542T)突变的小鼠模型,通过外观观察、显微CT成像及组织学染色(HE、Masson、Safranin O/Fast Green)对模型表型进行评估,以确认其是否重现SK特异的软骨终板缺陷与局部后凸畸形。利用单细胞RNA测序(scRNA-seq)结合生物信息学分析,解析软骨终板病理发育过程中关键的致病软骨细胞亚群及其靶分子调控网络。通过单细胞流式分选致病性软骨细胞亚群,并进一步利用免疫组化(immunohistochemistry,IHC)、免疫共沉淀(co-immunoprecipitation,Co-IP)验证FLNB^(I1542T)对c-Jun蛋白表达水平的影响;利用定量聚合酶链式反应(quantitative polymerase chain reaction,qPCR)、双荧光素酶报告基因等实验分析c-Jun对细胞外基质(extracellular matrix,ECM)稳态关键分子Serpinh1的转录激活调控,并利用免疫组化、Western blot分析Jun对ECM稳态的调控作用。结果:通过对先证者全外显子测序,鉴定出一个杂合FLNB c.4625T>C(p.Ile1542Thr)突变,与患者表型共分离,且计算预测提示其破坏蛋白稳定性。利用CRISPR-Cas9技术构建的FLNB^(I1542T)基因敲入小鼠,在生长发育过程中表现出与人SK患者相似的进行性胸腰段后凸、椎体体积与长度减小、骨化延迟及终板凹陷等影像学与组织病理学特征。单细胞转录组测序分析揭示,突变主要靶向并损害了终板软骨中的软骨形成细胞亚群的功能,导致该群细胞中与“软骨发育”和“细胞外基质组织”相关的基因表达程序显著下调。分子机制研究表明,FLNB^(I1542T)突变削弱了转录因子c-Jun的蛋白水平及其转录活性。c-Jun可直接结合并激活分子伴侣Serpinh1的启动子,而FLNB^(I1542T)突变导致的Jun功能抑制致使SERPINH1表达显著下降。SERPINH1的下游关键客户蛋白,包括COL2A1、COL9A3和COL11A2等维持ECM稳态的胶原蛋白,其表达也随之降低,从而破坏了软骨终板的ECM完整性。功能挽救实验证实,过表达Jun可逆转由FLNB^(I1542T)突变引起的SERPINH1及其下游胶原蛋白的表达下调。结论:FLNB^(I1542T)通过损害Jun的转录活性,抑制SERPINH1表达,从而破坏ECM胶原稳态,驱动SK的软骨终板缺陷与后凸畸形。
文摘研究了单个线性关系是可闭线性关系的充分必要条件;并对L0=(A B C D),其中A,B,C,D是相应Hilbert空间上的线性关系,利用C相对A的有界性与B相对D的有界性及A,D的可闭性,推出了L_(0)也是可闭线性关系;同时,对于有界线性算子S=(S_(1) S_(2) S_(3) S_(4)),得到当满足一定条件时L_(0)-μS的Frobenius-Schur分解公式,并得到了当L_(0)可闭时L_(0)的表达式,最后研究了L_(0)的S-本质谱。
