目的:比较青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者与家属对脊柱侧凸研究学会-22(Scoliosis Research Society-22,SRS-22)量表认知一致性的差异,明确影响SRS-22量表各维度得分的临床及影像学参数。方法:2019年1...目的:比较青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者与家属对脊柱侧凸研究学会-22(Scoliosis Research Society-22,SRS-22)量表认知一致性的差异,明确影响SRS-22量表各维度得分的临床及影像学参数。方法:2019年1月~2020年1月于我院就诊的46例AIS患者及其家属在治疗前分别填写SRS-22量表,患者中女性37例,男性9例,年龄11~19岁(13.6±1.8岁)。比较AIS患者与家属在SRS-22量表各维度得分的一致性,分析患者性别、年龄、身体质量指数(BMI)、病程、侧凸主弯部位、主弯Cobb角、轴向躯干旋转角(ATR)与SRS-22量表各维度的相关性。结果:AIS患者自评SRS-22量表疼痛、心理状况、功能状况、自我形象得分和总分分别为4.6±0.5、4.0±0.8、4.4±0.6、3.6±0.6和4.2±0.5分,家属评价各维度得分分别为4.6±0.5、4.1±0.7、4.2±0.7、3.2±0.6和4.1±0.5分,患者疼痛、心理状况得分与家属无显著性差异(P=0.868、0.195),功能状况、自我形象得分和总分高于家属,差异有统计学意义(P=0.048、<0.001和0.038)。患者自评年龄与心理状况得分呈显著性负相关(r=-0.343,P=0.020),主弯Cobb角度数与功能状况得分呈显著性负相关(r=-0.366,P=0.012),病程、BMI、ATR与各维度得分无显著相关性(P>0.05);家属评价各维度得分与患者年龄、主弯Cobb角度数、病程、BMI、ATR均无显著相关性。女性患者的家属在疼痛亚维度平均得分低于男性患者的家属,差异有统计学意义(4.5±0.6分vs 5.0±0.1,P=0.017);其他维度得分无统计学差异(P>0.05)。结论:AIS患者对功能状况和自我形象维度的满意度高于其家属,双方在疼痛和心理状况方面具有较好的认知一致性,年龄、主弯Cobb角分别是影响AIS患者SRS-22量表疼痛、功能状况维度得分的因素。展开更多
采用基于电磁补偿原理的精密天平,研制了一种微纳力值标准装置。通过高等级的标准砝码对天平进行校准,实现标准装置力值的SI溯源,在500 n N^500μN范围的力值测量标准不确定度小于0.7%。该装置用于对原子力显微镜(AFM)微悬臂弹性常数和...采用基于电磁补偿原理的精密天平,研制了一种微纳力值标准装置。通过高等级的标准砝码对天平进行校准,实现标准装置力值的SI溯源,在500 n N^500μN范围的力值测量标准不确定度小于0.7%。该装置用于对原子力显微镜(AFM)微悬臂弹性常数和微小力值传感器的力值提供准确的溯源。采用多自由度位置调整系统调整被测微悬臂或传感器的位置及俯仰角度,提高了定位准确度。对几种不同弹性常数的AFM微悬臂进行测量,测量结果的标准偏差小于1.6%,满足高准确度微小力值测量的要求。展开更多
Different from sculling forward of water striders with their hairy water-repellent legs, water spiders walked very quickly on water surfaces. By using a shadow method, the walking of water spiders had been studied. Th...Different from sculling forward of water striders with their hairy water-repellent legs, water spiders walked very quickly on water surfaces. By using a shadow method, the walking of water spiders had been studied. The three-dimensional trajectories and the supporting forces of water spider legs during walking forward were achieved. Results showed that the leg movement could be divided into three phases： slap, stroke, and retrieve. Employing an effective strategy to improving walking efficiency, the sculling legs supported most of its body weight while other legs were lifted to reduce the lateral water resistance, which was similar to the strategy of water striders. These findings could help guiding the design of water walking robots with high efficiency.展开更多
Shear tests of an electrorheological fluid with pre-applied electric field and compression along the fleld direction are carried out. The results show that pre-compressions can increase the shear yield stress up to te...Shear tests of an electrorheological fluid with pre-applied electric field and compression along the fleld direction are carried out. The results show that pre-compressions can increase the shear yield stress up to ten times. Under the same external electric field strength, a higher compressive strain corresponds to a larger shear yield stress enhancement but with slight current density decrease, which shows that the particle interaction potentials are not increased by compressions but the compression-induced chain aggregation dominates the shear yield stress improvement. This pre-compression technique might be useful for developing high performance flexible ER or magnetorheological couplings.展开更多
文摘采用基于电磁补偿原理的精密天平,研制了一种微纳力值标准装置。通过高等级的标准砝码对天平进行校准,实现标准装置力值的SI溯源,在500 n N^500μN范围的力值测量标准不确定度小于0.7%。该装置用于对原子力显微镜(AFM)微悬臂弹性常数和微小力值传感器的力值提供准确的溯源。采用多自由度位置调整系统调整被测微悬臂或传感器的位置及俯仰角度,提高了定位准确度。对几种不同弹性常数的AFM微悬臂进行测量,测量结果的标准偏差小于1.6%,满足高准确度微小力值测量的要求。
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51323006 and 51425502)the Tribology Science Fund of State Key Laboratory of Tribology(Grant No.SKLTKF17B18)
文摘Different from sculling forward of water striders with their hairy water-repellent legs, water spiders walked very quickly on water surfaces. By using a shadow method, the walking of water spiders had been studied. The three-dimensional trajectories and the supporting forces of water spider legs during walking forward were achieved. Results showed that the leg movement could be divided into three phases： slap, stroke, and retrieve. Employing an effective strategy to improving walking efficiency, the sculling legs supported most of its body weight while other legs were lifted to reduce the lateral water resistance, which was similar to the strategy of water striders. These findings could help guiding the design of water walking robots with high efficiency.
基金Supported by the National Natural Science Foundation of China with Grant No 50875152, and FANEDD of China under Grant No 200432.
文摘Shear tests of an electrorheological fluid with pre-applied electric field and compression along the fleld direction are carried out. The results show that pre-compressions can increase the shear yield stress up to ten times. Under the same external electric field strength, a higher compressive strain corresponds to a larger shear yield stress enhancement but with slight current density decrease, which shows that the particle interaction potentials are not increased by compressions but the compression-induced chain aggregation dominates the shear yield stress improvement. This pre-compression technique might be useful for developing high performance flexible ER or magnetorheological couplings.
