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Prevalence of myopia is increasing worldwide. Outdoor activity is one of the most important environmental factors for myopia control. Here we show that violet light (VL, 360–400 nm wavelength) suppresses myopia progression. First, we confirmed that VL suppressed the axial length (AL) elongation in the chick myopia model. Expression microarray analyses revealed that myopia suppressive gene EGR1 was upregulated by VL exposure. VL exposure induced significantly higher upregulation of EGR1 in chick chorioretinal tissues than blue light under the same conditions. Next, we conducted clinical research retrospectively to compare the AL elongation among myopic children who wore eyeglasses (VL blocked) and two types of contact lenses (partially VL blocked and VL transmitting). The data showed the VL transmitting contact lenses suppressed myopia progression most. These results suggest that VL is one of the important outdoor environmental factors for myopia control. Since VL is apt to be excluded from our modern society due to the excessive UV protection, VL exposure can be a preventive strategy against myopia progression.

When sand particles and volcanic ash are ingested into jet engines, they become molten droplets and are solidified on the surfaces of the turbine blades and endwalls. This is called the deposition phenomenon, and it causes serious problems in the aircraft, e.g., deterioration of the turbine performance and disturbing the cooling flow of the turbine blade. Therefore, the mechanism of the deposition phenomenon should be clarified in order to predict or prevent engine failure. In the present study, we perform three-dimensional numerical simulations of the deposition behavior of a single molten droplet on a cooled substrate using an explicit-moving particle simulation method. The results show a reasonable agreement with the experimental data. We confirm the formation of finger-like-structures that have the characteristic shape of a droplet that has adhered to an edge, and we also investigate effects of the impact angle on the deposition phenomenon.

Background/aims We developed a novel technology consisting of violet light (VL)-emitting glasses and defined the combination of VL irradiation and riboflavin treatment as KeraVio. Our goal was to evaluate the clinical results of KeraVio in patients with progressive corneal ectasia. Methods Eyes were exposed to VL (375 nm, irradiance 310 µW/cm2)-emitting glasses for 3 hours daily for 6 months, and a riboflavin solution was administered onto the corneal epithelium six times during each 3-hour VL irradiation. The primary end point was a change in the maximum keratometry (Kmax) value over 6 months compared with that over the 1 year before baseline. Results The efficacy of KeraVio was evaluated in 20 eyes with severe progression, and its safety was evaluated in all 40 eyes. The mean changes in Kmax over the 1 year before baseline and during the 6-month observation period were 6.03±3.41 dioptres (D) and -0.81±3.34 D, respectively (p=0.002). At 6 months, the Kmax value decreased by more than 2 D in 4 eyes (20%), remained within 2 D in 13 eyes (65%), and increased by 2 D or more in 3 eyes (15%). The corneal stromal demarcation line was identified in 16 eyes (80%), and its depth was 206.3±54.9 µm at 1 month. No significant decrease in endothelial cell density, lenticular opacity or transient corneal haze was noted. Conclusion Based on our 6-month results, daily treatment of progressive corneal ectasia with KeraVio can halt disease progression without any safety concerns. [ABSTRACT FROM AUTHOR]