Virtual reality training improves accommodative facility and accommodative range

AIM: To evaluate the effects of virtual reality(VR) training on different parameters of vision.METHODS: Sixty individuals ranged 18-60 years old with asthenopia were randomly divided into short-term(n=40) and long-term(n=20) treatment groups. They were given a specially designed VR training device only once for 15 min or 3-4 times a day for 15 min each time for 1 mo. The visual acuity, spherical equivalent, accommodative range, accommodative facility, pupil size, and visual fatigue were evaluated before(control) and after VR training. RESULTS: The visual acuity, accommodative range, and accommodative facility increased in subjects of the shortterm treatment group, whereas their pupil size contracted significantly. No significant changes in spherical equivalent and visual fatigue were observed. The changes in distant vision and corrected visual acuity were positively correlated with those in pupil size, but not with spherical equivalent. The accommodative range and accommodative facility improved significantly in subjects of the long-term treatment group. No significant changes in visual acuity, spherical equivalent, pupil size, and visual fatigue were noted. CONCLUSION: VR training can improve the accommodative range and accommodative facility of human eyes. Although short-term VR training can transiently improve vision, which probably due to bright light adaptation, there is no evidence that it can improve myopia.

利用剪切黏弹性模量对大鼠肝纤维化流变特性进行分析和建模(英文)

研究目的:肝脏的纤维化进程改变肝脏组织的流变属性。创新要点:本文利用剪切黏弹性模量描绘并比较了大鼠肝脏F0期到F4期的纤维化过程。研究方法:两个黏弹性模型,即Zener模型和Voigt模型用于解释流变力学测试得到的实验数据,由此得到每个纤维化分期的肝脏弹性和黏性值。重要结论:肝脏中度纤维化(≤F2期)与黏弹性值密切相关。Zener模型的弹性均值E1从F0期的(0.452±0.094)kPa增加到F2期的(1.311±0.717)kPa,而Voigt模型的弹性均值E从F0期的(0.618±0.089)kPa增加到F2期的(1.701±0.844)kPa。Zener模型的黏性均值从F0期的(3.499±0.186)Pa·s增加到F2期的(4.947±1.811)Pa·s,而Voigt模型的黏性均值从F0期的(3.379±0.316)Pa·s增加到F2期的(4.625±1.296)Pa·s。无论选用哪个黏弹性模型,在F1期和F2期,肝脏弹性值的标准差比黏性值的标准差变化要小。因此,测得的弹性比黏性更有效地区分肝纤维化F0期到F2期。