目的探讨晚孕期频谱多普勒超声、三维能量多普勒超声(3D-PDU)及剪切波弹性成像(SWE)评估妊娠期糖尿病(GDM)患者胎盘功能的价值。方法选择GDM患者58例为GDM组,年龄24~38岁,平均年龄30.7岁;孕龄28~40周,平均孕龄34.7周;孕前身体质量指数(B...目的探讨晚孕期频谱多普勒超声、三维能量多普勒超声(3D-PDU)及剪切波弹性成像(SWE)评估妊娠期糖尿病(GDM)患者胎盘功能的价值。方法选择GDM患者58例为GDM组,年龄24~38岁,平均年龄30.7岁;孕龄28~40周,平均孕龄34.7周;孕前身体质量指数(BMI)18.3~33.7 kg/m^(2),平均BMI 23.6 kg/m^(2);空腹、口服葡萄糖后1 h、2 h血糖分别为3.97~6.58、7.45~13.17、4.62~12.82 mmol/L,平均血糖分别为5.20、9.94、8.34 mmol/L。正常孕妇70例为对照组,年龄21~42岁,平均年龄29.6岁;孕龄28~41周,平均孕龄35.1周;孕前BMI 16.2~32.0 kg/m^(2),平均BMI 22.8 kg/m^(2)。常规超声检查胎儿双顶径、头围、腹围、股骨长、胎龄、胎儿体质量、胎盘厚度、羊水量。应用频谱多普勒超声获得胎儿脐动脉(UA)、大脑中动脉(MCA)及孕妇子宫动脉(UtA)的血流参数[收缩期/舒张末期峰值速度比(S/D)、搏动指数(PI)、阻力指数(RI)],计算脑-胎盘比(CPR);通过3D-PDU获得胎盘能量指数[血管血流指数(VFI)、血流指数(FI)、血管指数(VI)];应用SWE测得胎盘中央及边缘的平均弹性模量(E)。比较两组数据,绘制受试者工作特性(ROC)曲线对各参数进行评价。结果GDM组与对照组检查时胎儿双顶径、头围、腹围、股骨长、胎龄、胎儿体质量、胎盘厚度、羊水量比较,差异均无统计学意义(P>0.05)。两组孕妇产次、分娩方式和新生儿出生体质量、Apgar 1 min和5 min评分比较,差异均无统计学意义(P>0.05)。与对照组比较,GDM组不良妊娠结局的发生率升高(25.9%vs 11.4%),UtA血流参数升高(S/D:1.94±0.30 vs 1.82±0.18;PI:0.73±0.16 vs 0.65±0.11;RI:0.48±0.06 vs 0.45±0.05),GDM组胎盘能量指数降低(VI:11.76±2.92 vs 15.81±2.98;FI:33.44±2.80 vs 34.79±2.50;VFI:3.94±1.05 vs 5.53±1.20),GDM组胎盘中央及边缘E升高(5.94±0.89 vs 4.81±0.65;6.12±1.01 vs 4.88±0.71),差异均有统计学意义(P<0.05);两组UA、MCA血流参数(S/D、PI、RI)及CPR比较,差异无统计学意义(P>0.05)。ROC曲线分析结果显示,UtA-PI、胎盘VFI、胎盘中央E在单一模态超声中诊断价值较高,三项联合评估的曲线下面积(AUC)为0.914,对GDM诊断价值较单一参数明显提高。结论频谱多普勒超声、3D-PDU、SWE可评估晚孕期GDM患者胎盘功能,多模态超声联合应用可提高诊断效能,为GDM的临床管理提供参考。展开更多
Copper wire, serving as a cost-saving alternative to gold wire, has been used in many high-end thermosonic ball bonding applications. In this paper, the bond shear force, bond shear strength, and the ball bond diamete...Copper wire, serving as a cost-saving alternative to gold wire, has been used in many high-end thermosonic ball bonding applications. In this paper, the bond shear force, bond shear strength, and the ball bond diameter are adopted to evaluate the bonding quality. It is concluded that the ef/~cient ultrasonic power is needed to soften the ball to form the copper bonds with high bonding strength. However, excessive ultrasonic power would serve as a fatigue loading to weaken the bonding. Excessive or less bonding force would cause cratering in the silicon.展开更多
From results obtained in the rheological characterization of a 4% dispersion of flamboyant gum with the HaakeRT20 viscometer, for different conditions of pH = 3.0 and 9.0, temperature 5°C, 25°C and 45°C...From results obtained in the rheological characterization of a 4% dispersion of flamboyant gum with the HaakeRT20 viscometer, for different conditions of pH = 3.0 and 9.0, temperature 5°C, 25°C and 45°C, the data of the rheological behavior of the gum dispersions were fitted to the power law model. To understand and predict the behavior of this gum, a model of Lattice Boltzmann D2Q9 was developed for the behavior, in addition to simulations for the conditions handled in the experiments performed with the HaakeRT20 viscometer.展开更多
In order to understand the mechanism of the confinement bifurcation and H-mode power threshold in magnetically confined plasma,a new dynamical model of the L-H transition based on edge instability phase transition（E...In order to understand the mechanism of the confinement bifurcation and H-mode power threshold in magnetically confined plasma,a new dynamical model of the L-H transition based on edge instability phase transition（EIPT） has been developed.With the typical plasma parameters of the EAST tokamak,the self-consistent turbulence growth rate is analyzed using the simplest case of pressure-driven ballooning-type instability,which indicates that the L-H transition can be caused by the stabilization of the edge instability through EIPT.The weak E？×？B flow shear in L-mode is able to increase the ion inertia of the electrostatic motion by increasing the radial wave number of the tilted turbulence structures,which play an important role for accelerating the trigger process of EIPT rather than directly to suppress the turbulent transport.With the acceleration mechanism of E？×？B flow shear,fast L-H and H-L transitions are demonstrated under the control of the input heating power.Due to the simplified scrape-offlayer boundary condition applied,the ratio between the heating powers at the H-L and L-H transition respectively differs from the ratio by Nusselt number.The results of the modeling reveal a scaling of the power threshold of the L-H transition,P_（L-H）？∝？n^（0.76） B^（0.8） for deuterium plasma.It is found finite Larmor radius induces an isotope effect of the H-mode power threshold.展开更多
文摘目的探讨晚孕期频谱多普勒超声、三维能量多普勒超声(3D-PDU)及剪切波弹性成像(SWE)评估妊娠期糖尿病(GDM)患者胎盘功能的价值。方法选择GDM患者58例为GDM组,年龄24~38岁,平均年龄30.7岁;孕龄28~40周,平均孕龄34.7周;孕前身体质量指数(BMI)18.3~33.7 kg/m^(2),平均BMI 23.6 kg/m^(2);空腹、口服葡萄糖后1 h、2 h血糖分别为3.97~6.58、7.45~13.17、4.62~12.82 mmol/L,平均血糖分别为5.20、9.94、8.34 mmol/L。正常孕妇70例为对照组,年龄21~42岁,平均年龄29.6岁;孕龄28~41周,平均孕龄35.1周;孕前BMI 16.2~32.0 kg/m^(2),平均BMI 22.8 kg/m^(2)。常规超声检查胎儿双顶径、头围、腹围、股骨长、胎龄、胎儿体质量、胎盘厚度、羊水量。应用频谱多普勒超声获得胎儿脐动脉(UA)、大脑中动脉(MCA)及孕妇子宫动脉(UtA)的血流参数[收缩期/舒张末期峰值速度比(S/D)、搏动指数(PI)、阻力指数(RI)],计算脑-胎盘比(CPR);通过3D-PDU获得胎盘能量指数[血管血流指数(VFI)、血流指数(FI)、血管指数(VI)];应用SWE测得胎盘中央及边缘的平均弹性模量(E)。比较两组数据,绘制受试者工作特性(ROC)曲线对各参数进行评价。结果GDM组与对照组检查时胎儿双顶径、头围、腹围、股骨长、胎龄、胎儿体质量、胎盘厚度、羊水量比较,差异均无统计学意义(P>0.05)。两组孕妇产次、分娩方式和新生儿出生体质量、Apgar 1 min和5 min评分比较,差异均无统计学意义(P>0.05)。与对照组比较,GDM组不良妊娠结局的发生率升高(25.9%vs 11.4%),UtA血流参数升高(S/D:1.94±0.30 vs 1.82±0.18;PI:0.73±0.16 vs 0.65±0.11;RI:0.48±0.06 vs 0.45±0.05),GDM组胎盘能量指数降低(VI:11.76±2.92 vs 15.81±2.98;FI:33.44±2.80 vs 34.79±2.50;VFI:3.94±1.05 vs 5.53±1.20),GDM组胎盘中央及边缘E升高(5.94±0.89 vs 4.81±0.65;6.12±1.01 vs 4.88±0.71),差异均有统计学意义(P<0.05);两组UA、MCA血流参数(S/D、PI、RI)及CPR比较,差异无统计学意义(P>0.05)。ROC曲线分析结果显示,UtA-PI、胎盘VFI、胎盘中央E在单一模态超声中诊断价值较高,三项联合评估的曲线下面积(AUC)为0.914,对GDM诊断价值较单一参数明显提高。结论频谱多普勒超声、3D-PDU、SWE可评估晚孕期GDM患者胎盘功能,多模态超声联合应用可提高诊断效能,为GDM的临床管理提供参考。
文摘Copper wire, serving as a cost-saving alternative to gold wire, has been used in many high-end thermosonic ball bonding applications. In this paper, the bond shear force, bond shear strength, and the ball bond diameter are adopted to evaluate the bonding quality. It is concluded that the ef/~cient ultrasonic power is needed to soften the ball to form the copper bonds with high bonding strength. However, excessive ultrasonic power would serve as a fatigue loading to weaken the bonding. Excessive or less bonding force would cause cratering in the silicon.
文摘From results obtained in the rheological characterization of a 4% dispersion of flamboyant gum with the HaakeRT20 viscometer, for different conditions of pH = 3.0 and 9.0, temperature 5°C, 25°C and 45°C, the data of the rheological behavior of the gum dispersions were fitted to the power law model. To understand and predict the behavior of this gum, a model of Lattice Boltzmann D2Q9 was developed for the behavior, in addition to simulations for the conditions handled in the experiments performed with the HaakeRT20 viscometer.
基金supported by National Natural Science Foundation of China under Contract Nos.11575235 and 11422546China Postdoctoral Science Foundation under Contract No.2016M602043+2 种基金the National Magnetic Confinement Fusion Science Program of China under Contract No.2015GB101002Key Research Program of Frontier Sciences,CAS,Grant No.QYZDB-SSW-SLH001K C Wong Education Foundation
文摘In order to understand the mechanism of the confinement bifurcation and H-mode power threshold in magnetically confined plasma,a new dynamical model of the L-H transition based on edge instability phase transition（EIPT） has been developed.With the typical plasma parameters of the EAST tokamak,the self-consistent turbulence growth rate is analyzed using the simplest case of pressure-driven ballooning-type instability,which indicates that the L-H transition can be caused by the stabilization of the edge instability through EIPT.The weak E？×？B flow shear in L-mode is able to increase the ion inertia of the electrostatic motion by increasing the radial wave number of the tilted turbulence structures,which play an important role for accelerating the trigger process of EIPT rather than directly to suppress the turbulent transport.With the acceleration mechanism of E？×？B flow shear,fast L-H and H-L transitions are demonstrated under the control of the input heating power.Due to the simplified scrape-offlayer boundary condition applied,the ratio between the heating powers at the H-L and L-H transition respectively differs from the ratio by Nusselt number.The results of the modeling reveal a scaling of the power threshold of the L-H transition,P_（L-H）？∝？n^（0.76） B^（0.8） for deuterium plasma.It is found finite Larmor radius induces an isotope effect of the H-mode power threshold.
