AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children.METHODS:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 ...AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children.METHODS:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this study.The whole randomization method was adopted to include classes as a group according to 1:1 randomized control.Classrooms in the control group were illuminated by usual light,and classrooms in the intervention group were illuminated by artificial natural light.All students received uncorrected visual acuity and best-corrected visual acuity measurement,non-cycloplegic autorefraction,ocular biometric examination,slit lamp and strabismus examination.Three-year follow-up,the students underwent same procedures.Myopia was defined as spherical equivalent refraction≤-0.50 D and uncorrected visual acuity<20/20.RESULTS:There were 894 students in the control group and 946 students in the intervention group with a mean±SD age of 7.50±0.53y.The three-year cumulative incidence rate of myopia was 26.4%(207 incident cases among 784 eligible participants at baseline)in the control group and 21.2%(164 incident cases among 774 eligible participants at baseline)in the intervention group[difference of 5.2%(95%CI,3.7%to 10.1%);P=0.035].There was also a significant difference in the three-year change in spherical equivalent refraction for the control group(-0.81 D)compared with the intervention group[-0.63 D;difference of 0.18 D(95%CI,0.08 to 0.28 D);P<0.001].Elongation of axial length was significantly different between in the control group(0.77 mm)and the intervention group[0.72 mm;difference of 0.05 mm(95%CI,0.01 to 0.09 mm);P=0.003].CONCLUSION:Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years.展开更多
Objective:To investigate the mechanical properties of a new type of biplane locking plate with wings in the treatment of middle clavicle fractures.Methods:Based on the CT data of a healthy adult male volunteer’s clav...Objective:To investigate the mechanical properties of a new type of biplane locking plate with wings in the treatment of middle clavicle fractures.Methods:Based on the CT data of a healthy adult male volunteer’s clavicle,a three-dimensional finite element model of the middle clavicle fracture was constructed by digital three-dimensional reconstruction technology,and the two kinds of fixation methods of single-plane locking plate(SP)and wing plate(WP)were simulated.Four load cases of axial compression,axial torsion,cantilever bending and pull-out were used to analyze the models.Results:①Under axial compression,axial torsion,cantilever bending and pull-out conditions,compared with SP,the stiffness phase of WP increased by 1.47%,5.82%,1.51%and 3.96%respectively,and the strain energy decreased by 1.50%,5.39%,1.48%and 3.49%respectively.②The stress distribution characteristics of WP under various load conditions were similar to SP,and the high stress area was located around the screw hole of the steel plate above the fracture gap;③Under the pull-out condition of WP,the peak value of screw hole surface stress was greatly reduced compared with SP,especially in the screw hole on both sides of the wing screws,which had higher resistance to pull out.Conclusion:The load-bearing mode of WP under various load conditions is similar to that of SP,and the stability is slightly higher than that of SP and in terms of pull-out resistance,WP has more obvious advantages.The biplane locking plate with wings is expected to be a more ideal choice for patients with comminuted fracture of the middle clavicle or with osteoporosis.展开更多
基金Guangdong Basic and Applied Basic Research Foundation(No.2019B1515120011)Medical Research,Foshan Health and Wellness Department(No.20220374).
文摘AIM:To assess the efficacy of artificial natural light in preventing incident myopia in primary school-age children.METHODS:This is a prospective,randomized control,intervention study.A total of 1840 students from 39 classes in 4 primary schools in Foshan participated in this study.The whole randomization method was adopted to include classes as a group according to 1:1 randomized control.Classrooms in the control group were illuminated by usual light,and classrooms in the intervention group were illuminated by artificial natural light.All students received uncorrected visual acuity and best-corrected visual acuity measurement,non-cycloplegic autorefraction,ocular biometric examination,slit lamp and strabismus examination.Three-year follow-up,the students underwent same procedures.Myopia was defined as spherical equivalent refraction≤-0.50 D and uncorrected visual acuity<20/20.RESULTS:There were 894 students in the control group and 946 students in the intervention group with a mean±SD age of 7.50±0.53y.The three-year cumulative incidence rate of myopia was 26.4%(207 incident cases among 784 eligible participants at baseline)in the control group and 21.2%(164 incident cases among 774 eligible participants at baseline)in the intervention group[difference of 5.2%(95%CI,3.7%to 10.1%);P=0.035].There was also a significant difference in the three-year change in spherical equivalent refraction for the control group(-0.81 D)compared with the intervention group[-0.63 D;difference of 0.18 D(95%CI,0.08 to 0.28 D);P<0.001].Elongation of axial length was significantly different between in the control group(0.77 mm)and the intervention group[0.72 mm;difference of 0.05 mm(95%CI,0.01 to 0.09 mm);P=0.003].CONCLUSION:Artificial natural light in the classroom of primary schools can result in reducing incidence rate of myopia during a period of three years.
基金Non-Fund Project of Science and Technology of Zhanjiang(No.2019B01067)Competitive Allocation Program of Science and Technology Fund of Zhanjiang(No.2019A01029)。
文摘Objective:To investigate the mechanical properties of a new type of biplane locking plate with wings in the treatment of middle clavicle fractures.Methods:Based on the CT data of a healthy adult male volunteer’s clavicle,a three-dimensional finite element model of the middle clavicle fracture was constructed by digital three-dimensional reconstruction technology,and the two kinds of fixation methods of single-plane locking plate(SP)and wing plate(WP)were simulated.Four load cases of axial compression,axial torsion,cantilever bending and pull-out were used to analyze the models.Results:①Under axial compression,axial torsion,cantilever bending and pull-out conditions,compared with SP,the stiffness phase of WP increased by 1.47%,5.82%,1.51%and 3.96%respectively,and the strain energy decreased by 1.50%,5.39%,1.48%and 3.49%respectively.②The stress distribution characteristics of WP under various load conditions were similar to SP,and the high stress area was located around the screw hole of the steel plate above the fracture gap;③Under the pull-out condition of WP,the peak value of screw hole surface stress was greatly reduced compared with SP,especially in the screw hole on both sides of the wing screws,which had higher resistance to pull out.Conclusion:The load-bearing mode of WP under various load conditions is similar to that of SP,and the stability is slightly higher than that of SP and in terms of pull-out resistance,WP has more obvious advantages.The biplane locking plate with wings is expected to be a more ideal choice for patients with comminuted fracture of the middle clavicle or with osteoporosis.
