Myopia is a common eye disease among children and adolescents, and it is also a major and common public health problem for children and adolescents worldwide. Although the myopia rate among children and adolescents in different provinces , cities , and regions varies , the incidence of myopia is generally high , showing a trend of high incidence and younger age. Myopia in children and adolescents is closely related to sleep conditions . The sleep time of most children and adolescents in China does not reach the recommended length of time for this age group, and their sleep quality is poor, which affects their study and life. The biological connection and molecular mechanism between sleep and myopia are hot topics in clinical research . This article reviews the epidemiological characteristics of myopia and sleep status in children and adolescents , as well as the biological mechanisms between sleep and myopia , with the aim of providing a theoretical basis for preventing myopia in children and adolescents.

Objective: To investigate the association of physical activity and screen time with overweight and obesity among children and adolescents with special needs in Tianjin, so as to provide scientific evidence for childhood obesity prevention and intervention measures in the population. Methods: From January 2022 to June 2024, 296 children and adolescents with intellectual disabilities and autism spectrum disorders aged 2-18 years were recruited from special education schools and institutions in Tianjin. Height and weight were measured, and a standardized questionnaire was used to assess physical activity and screen time. Binary Logistic regression analysis was carried out to investigate the association of physical activity and screen time with overweight and obesity. Results: The prevalence of overweight and obesity among children and adolescents with special needs in Tianjin were 17.2% and 21.6%, respectively, and the combined prevalence of overweight and obesity was 38.9%. The median of moderatetovigorous physical activity (MVPA) time was 0.20 h/d, and physical activity sufficiency rate was 7.8%. The median of screen time was 1.79 h/d, and the screen time compliance rate was 68.2%. The binary Logistic regression results showed that lower levels of MVPA time and increased screen time were associated with a higher risk of overweight and obesity among children and adolescents with special needs [OR(95%CI)=1.80(1.06-3.07), 2.40(1.42-4.07),P<0.05]. Conclusions Insufficient physical activity and excessive screen time are associated with an increased risk of overweight and obesity among children and adolescents with special needs. Therefore, comprehensive intervention measures should be implemented as early as possible to prevent and reduce the incidence of overweight and obesity in this population.

Objective: To understand the subjective and objective comfort evaluations of students from different age groups on desks and chairs, so as to provide reference for standardized allocation and use of desks and chairs. Methods: From January to April 2024, a total of 2 446 students were selected from 26 schools in 13 districts (counties/cities) in Shanghai, Tianjin, and Wuxi from Jiangsu Province by using cluster random method, including students in kindergartens, primary schools, junior high schools,senior high schools, colleges and universities. Standardized procedures were used to measure the height and weight of participants, and the matching desks and chairs models were selected according to the height. The subjective comfort of students on matching desks and chairs was investigated, and their objective comfort was evaluated by using a self designed questionnaire. The χ 2 test was used to analyze the differences of subjective perception and objective evaluation in comfort between different types of desks and chairs. Results: About 84.1% of the students subjectively thought that large desks and small chairs were very comfortable or relatively comfortable, followed by large desks and chairs (75.7%), and the proportion of small desks and chairs was the lowest among the three types (46.2%), and the difference was statistically significant ( χ 2=722.46, P <0.01). The reporting rates of primary school, junior high school and senior high school students who subjectively considered large desks and chairs to be very comfortable/relatively comfortable were higher than that of other types of desks and chairs, and the differences were statistically significant ( χ 2=297.49, 252.82, 343.67, P <0.01). However, there was no significant difference in the subjective comfort evaluation of different types of desks and chairs among kindergarten children ( χ 2=3.21, P >0.05), and 66.3% of the students in colleges and universities felt very comfortable/relatively comfortable when they used the matching standard desks and chairs. The objective evaluation results of the comfort for the three types of desks and chairs were consistent with the subjective evaluation, but the proportions of the objective evaluation as very comfortable/relatively comfortable were higher than that of the subjective evaluation ( χ 2=20.76- 813.47, P <0.01). Conclusions Large desks and chairs, as well as large desks with small chairs are perceived comfortable, while small desks and chairs are perceived less comfortable. It is recommended to match the large desks and chairs or large desks and small chairs that are suitable for them according to the "standard", to promote physical and mental health of students.

Objective: To investigate the differences in the comfort of desks and chairs furniture among students with different body types according to the standard, so as to provide a reference for guiding students with overweight and obesity to choose the correct study furniture and revising the standards. Methods: From January to April 2024, 2 443 students from 26 schools in 13 districts (counties/cities) in Shanghai, Tianjin, and Jiangsu Province were selected by the cluster random sampling method to conduct physical examination. The subjective and objective evaluations of the comfort of height matched desks and chairs were investigated. The students were divided into non overweight, overweight, and obesity groups according to relevant criteria, and stratified analysis was performed. The χ 2 test was used to analyze differences in the comfort evaluations of desks and chairs among students with different body types. Results: Among the 2 443 students surveyed, 16.7% and 12.6% were respectively classified as overweight and obese. All students assigned the highest comfort ratings to large desks and small chairs (84.1%), and consistency was observed between students subjective and objective evaluations. The reporting rate of samll desks and chairs of obesity students subjective evaluation was lower (36.8%) than that of overweight and non overweight/obesity students (52.1%, 48.0%) ( χ 2=14.63, P <0.01). The overweight and obese group of primary school students had a worse evaluation of the comfort of large desks and chairs and small desks and chairs than those of the non overweight and obese groups( χ 2=15.78, 7.63, P <0.05). Among high school students, the overweight and obese group had worse evaluation of the comfort of large desks and chairs, as well as large desks and small chairs, than those of the non-overweight and obese groups( χ 2=9.62, 11.77, P <0.05). The objective evaluations revealed low compliance ratings on the posture of the thighs and calves for naturally forming an angle greater than 90° (55.6%), and headroom height under the table (50.3%) with small desks and chairs ( χ 2=94.05, 166.47, P <0.05). Conclusions Compared with non overweight/obese students, students with overweight and obese students report poor comfort evaluations of height matched desks and chairs. Revision of the standard should consider the body types of students, and evaluations of the comfort of desks and chairs furniture by students with overweight and obesity should be improved.

Objective: To understand the current situation and related factors of screening myopia among students in special education schools, so as to provide evidence for promoting the health level of this population. Methods: From November 2021 to December 2023, a total of 281 students from 6 special education schools in 5 districts of Tianjin were selected by cluster random sampling method for computer optometry visual acuity examination for non ciliary paralysis and questionnaire survey. Multiple Logistic regression was performed to analyze the influencing factors of screening myopia among special education students. Results: The screening myopia detection rate among these special education students in Tianjin was 27.0%, and the screening myopia detection rates of students with autism, developmental delays, and intellectual disabilities were 22.4%, 12.5%, and 33.0%, respectively. The degree of myopia increased with age ( χ 2 trend =22.65, P <0.01). Multivariate Logistic regression analysis showed that age(10-13 years old: OR =5.40, 14-17 years old: OR =8.40, 18-23 years old: OR =6.02), accommodation(non resident: OR =0.29), daily mobile phone usage ≥2 hours ( OR =2.37), and daily computer/tablet usage ≥2 hours ( OR =2.70) were the risk factors for screening myopia among special education students ( P <0.05). Conclusions The detection rate and degree of screening myopia increase with age in special education students. Prolonged screen time exposure is a primary risk factor for screening myopia in special education students. Effective myopia prevention and control strategies should be designed according to the characteristics of special education students.