Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but...Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but detuning, in detain. It is proved that the coupling level determines stability of the lasers by analyzing the eigenvalue equation. Critical case of locking is discussed via the phase difference equation. Quasi-period and stable states in the two lasers are investigated via varying the current, detuning and coupling level.展开更多
目的:探讨创伤性臂丛神经损伤的磁共振成像(MRI)三维循环相位稳态采集快速成像(three-dimensional fast imaging employing steady state acquisition with cycled phases,3D-FIESTA-C)序列和三点法非对称回波水脂分离成像(iterative de...目的:探讨创伤性臂丛神经损伤的磁共振成像(MRI)三维循环相位稳态采集快速成像(three-dimensional fast imaging employing steady state acquisition with cycled phases,3D-FIESTA-C)序列和三点法非对称回波水脂分离成像(iterative decomposition of water and fat with echo asymmetry and least squares estimation,IDEAL)序列特征及诊断价值。方法:对32例创伤性臂丛神经损伤患者进行术前MRI 3D-FIESTA-C及IDEAL序列检查后,再行图像后处理及诊断,总结臂丛神经损伤的MRI特征,将诊断结果与手术探查结果进行比较,评价术前MRI 3D-FIESTA-C联合IDEAL序列检查在诊断臂丛神经损伤中的作用。结果:12例患者术后证实共有39条节前神经损伤,3D-FIESTA-C序列显示出38条,其中31条神经根影像提示消失或离断,7条神经根丝减少、迂曲,无法连续追踪至椎间孔,同时可伴有神经根袖变钝、脊膜囊肿形成、硬脊膜增厚及脊髓形态信号异常改变。术前MRI 3D-FIESTA-C序列诊断臂丛神经节前损伤的灵敏度为97.5%,特异度为100%,准确率达98.3%。31例120条节后损伤中共12例45条节后神经断裂,其中7条伴纤维瘤形成,IDEAL序列显示42条节后神经根断裂,其他损伤表现为神经增粗,扭曲,走行僵直,周围结构水肿紊乱等。术前IDEAL序列诊断臂丛节后损伤的灵敏度为96.7%,特异度为100%,准确率为97.1%。结论:MRI3D-FIESTA-C联合IDEAL序列检查可清晰显示节前及节后臂丛神经损伤情况,对臂丛神经损伤的诊断符合率较高,可作为临床首选的无创性影像学方法。展开更多
We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to inve...We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to investigate the temporal evolution we first explore the statistical properties by means of weighting distribution and the Mandel parameter. It is found that the temporal evolution of the coherent states may exhibit the phenomena of quantum revivals and fractional revivals for a particular choice of position-dependent mass oscillator.展开更多
文摘Abstract We study dynamics in two mutually coupling multi-quantum-well lasers. We carry out theoretical and numerical analysis of synchronization, anti-synchronization, in-phase locking in the two identical lasers but detuning, in detain. It is proved that the coupling level determines stability of the lasers by analyzing the eigenvalue equation. Critical case of locking is discussed via the phase difference equation. Quasi-period and stable states in the two lasers are investigated via varying the current, detuning and coupling level.
文摘目的:探讨创伤性臂丛神经损伤的磁共振成像(MRI)三维循环相位稳态采集快速成像(three-dimensional fast imaging employing steady state acquisition with cycled phases,3D-FIESTA-C)序列和三点法非对称回波水脂分离成像(iterative decomposition of water and fat with echo asymmetry and least squares estimation,IDEAL)序列特征及诊断价值。方法:对32例创伤性臂丛神经损伤患者进行术前MRI 3D-FIESTA-C及IDEAL序列检查后,再行图像后处理及诊断,总结臂丛神经损伤的MRI特征,将诊断结果与手术探查结果进行比较,评价术前MRI 3D-FIESTA-C联合IDEAL序列检查在诊断臂丛神经损伤中的作用。结果:12例患者术后证实共有39条节前神经损伤,3D-FIESTA-C序列显示出38条,其中31条神经根影像提示消失或离断,7条神经根丝减少、迂曲,无法连续追踪至椎间孔,同时可伴有神经根袖变钝、脊膜囊肿形成、硬脊膜增厚及脊髓形态信号异常改变。术前MRI 3D-FIESTA-C序列诊断臂丛神经节前损伤的灵敏度为97.5%,特异度为100%,准确率达98.3%。31例120条节后损伤中共12例45条节后神经断裂,其中7条伴纤维瘤形成,IDEAL序列显示42条节后神经根断裂,其他损伤表现为神经增粗,扭曲,走行僵直,周围结构水肿紊乱等。术前IDEAL序列诊断臂丛节后损伤的灵敏度为96.7%,特异度为100%,准确率为97.1%。结论:MRI3D-FIESTA-C联合IDEAL序列检查可清晰显示节前及节后臂丛神经损伤情况,对臂丛神经损伤的诊断符合率较高,可作为临床首选的无创性影像学方法。
文摘We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to investigate the temporal evolution we first explore the statistical properties by means of weighting distribution and the Mandel parameter. It is found that the temporal evolution of the coherent states may exhibit the phenomena of quantum revivals and fractional revivals for a particular choice of position-dependent mass oscillator.
