Abstract The study examines the development and application of microclimate standards for primary and secondary school classrooms, so as to ensure and promote the healthy growth of primary and secondary school students. The paper systematically reviews relevant domestic and international standards, analyzes the problems and shortcomings arising from their practical application and proposes effective countermeasures, in order to provide robust references aimed at optimizing the classroom environment in primary and secondary schools for student health, as well as offering practical support to advance the construction of a healthy China.

Objective: To understand the microclimate in primary and secondary school classrooms for the study period during the winter heating season, so as to provide a reference for the revision and improvement of relevant health standards. Methods: In December 2024, stratified random sampling was used to select 30 primary and secondary schools and 180 classrooms from the northern regions with centralized heating (Liaoning Province, Tianjin City) and the southern regions without centralized heating (Shanghai City, Anhui Province, and Jiangxi Province). Indoor temperature, relative humidity, wind speed, CO 2 and other indicators were measured on site. Variance analysis, t-test, Mann-Whitney U test and Kruskal-Wallis H test were used to analyze the differences in the microclimate of classrooms among regions and urban and rural differences. Results: The average temperature in the middle of the classrooms tested on site was (16.47±4.72)℃, and the variance analysis showed that the difference between the regions was statistically significant ( F=27.80, P <0.01). Among them, Tianjin had the highest average temperature of (20.43± 2.12 )℃, followed by Liaoning (19.03±2.23)℃, Shanghai (15.33±5.32)℃, Anhui (12.79±1.74)℃, and Jiangxi (11.69± 1.68 )℃. Horizontal temperature difference was 0.90 (0.50, 1.60)℃, the vertical temperature difference was 0.20 (0.10,0.60)℃, the average relative humidity was (44.39±16.16)%, the wind speed was 0.03(0.01,0.11)m/s, and the differences among different provinces and cities were statistically significant ( H/F =40.62, 82.69, 95.06, 55.28, all P <0.01). The average CO 2 volume concentration in urban areas of Tianjin, Liaoning, and Shanghai was 0.21(0.16,0.30)%, and there was no statistically significant difference ( H=4.65, P =0.10). There were grade differences in relative humidity ( F =3.71, 6.21) and CO 2 ( H =14.72, 12.92) in the north and the south (all P <0.05). In addition, the temperature, relative humidity, wind speed and CO 2 in the middle of the classroom were 42.8%, 67.8%, 100.0% and 22.2% respectively. Conclusions The temperature in the middle of the classroom in the non centralized heating area is lower than the standard, the relative humidity of classroom in the centralized heating area is lower than the standard，and the CO 2 in the classroom in winter is lower than the standard. It is recommended to install heating facilities in schools with low temperatures to increase the temperature and increase the frequency of ventilation in classrooms or adopt mechanical ventilation strategies to reduce CO 2 volume concentration.

Objective: To evaluate the classroom environmental management and CO 2 volume concentration in primary and secondary schools from Liaoning, Tianjin, and Shanghai, thereby providing a scientific basis for developing targeted strategies to improve classroom air quality. Methods: From December 16 to 26, 2024, by using stratified random cluster sampling method, the questionnaire survey was conducted in 72 primary and secondary schools (24 each of primary, junior high, and regular high schools) across Liaoning, Tianjin and Shanghai. Information on heating, ventilation and other classroom environmental management was collected. Additionally, 108 classrooms were selected for on site microclimate measurements, including temperature, humidity, wind speed and CO 2 volume concentration. Univariate analysis and multiple linear regression models were employed to explore related factors of classroom CO 2 volume concentration. Results: Among the three provinces/municipalities, 20.8% of schools regularly monitored the microclimate. The overall compliance rate for classroom CO 2 volume concentration was 17.6%. Multiple linear regression analysis showed that CO 2 volume concentration in regular and junior high school classrooms were higher than in primary school classrooms ( β=0.067, 0.046, 95%CI =0.036-0.099, 0.013-0.080); classrooms ventilated regularly in the morning and afternoon had higher CO 2 volume concentration than those ventilated during every break between classes ( β=0.043, 95%CI = 0.007- 0.080); both temperature ( β=0.010, 95%CI =0.004-0.016) and humidity ( β=0.003, 95%CI =0.002-0.004) were positively correlated with CO 2 volume concentration (all P <0.05). Conclusions Excessive CO 2 volume concentration in primary and secondary school classrooms is a prominent issue, and ventilation frequency is a key intervenable factor for controlling CO 2 levels. It is recommended to promote ventilation during every break between classes as a core management measure and to emphasize air quality supervision in regular high school classrooms.

Objective: To evaluate the current situation of thermal environment in primary and secondary school classrooms during winter, and to analyze students thermal comfort needs, so as to provide a basis for improving classroom thermal environment. Methods: From December 16 to 26, 2024, a stratified cluster random sampling method was used to select 90 classrooms from 15 primary and secondary schools in centralized/air conditioned heating areas(Liaoning Province, Tianjin City, Shanghai City) and naturally ventilated areas(Anhui Province and Jiangxi Province)for on site environmental measurement. A questionnaire survey was conducted among 743 students. The differences between groups using the χ 2 test were compared. Based on actual measurement data, a predicted mean vote prepared percentage of dissatisfied (PMV-PPD) model for centralized/air conditioned classrooms and an adaptive model for naturally ventilated classrooms were established, and the thermal neutral temperature and comfort interval were calculated. Results: The average outdoor temperature during on site measurement was 4.00(0.20，7.00)℃. In classrooms with centralized or air conditioned heating systems, the measured average temperature was (19.33±2.59)℃, with a thermal comfort range of 20.35-25.35 ℃ and a thermal neutral temperature of 22.85 ℃. And 13.92% of students reported feeling cold, while 80.80% felt comfortable. In classrooms with natural ventilation, the measured average temperature was (12.26±1.83)℃, with a thermal neutral temperature of 19.67 ℃ and a thermal comfort range of 16.17-23.17 ℃. About 48.33% of students reported feeling cold, and 49.81 % felt comfortable.The results of univariate analysis showed that there were statistically significant differences in shoe thickness, temperature sensation, relative humidity sensation and wind speed sensation between centralized/air conditioned heating areas ( χ 2= 7.01 , 31.47, 13.57, 13.80,all P <0.05). There were also statistically significant differences in school stage for primary and secondary school students, body mass index, classroom location for seat, temperature sensation, relative humidity sensation and wind speed sensation between naturally ventilated areas ( χ 2=42.13, 11.13, 11.04, 60.39, 29.27, 38.46,all P <0.05). Conclusions There are differences in thermal environment and students subjective thermal comfort in primary and secondary schools under different ventilation modes in winter. The temperature standards for heated classrooms should be revised, and differentiated environmental regulation strategies should be adopted based on different ventilation methods to improve students health and comfort levels.

Objective:To explore the association between healthy lifestyle and co-morbidity of overweight/obesity and myopia in adolescents.Methods:Based on the Shanghai Municipal Dynamic Cohort of Student Common Diseases, we used the group-based trajectory model (GBTM) to establish a model for the development of adolescents' healthy lifestyle trajectories aged 11-14 years and the Cox proportional hazard regression model to assess the effects of different healthy lifestyles on the co-morbidity of overweight/obesity and myopia in adolescents.Results:A total of 2 331 adolescents were included in the analysis. The average follow-up time was 1.87 years, with age of (11.44±0.45) years at the initial follow-up, among 1 106 boys and 1 225 girls. During the 2-year follow-up period, the incidence rates of overweight/obesity, myopia, and co-occurrence of overweight/obesity and myopia were 25.9%, 77.0%, and 13.7%, respectively. GBTM identified 3 healthy lifestyles: the unhealthy group (7.3%), the relatively healthy group (50.2%), and the healthy group (42.5%). The risk of overweight/obesity was lower in the relatively healthy group than in the unhealthy group ( HR=0.694, 95% CI: 0.508-0.947). There was no statistically significant association between the GBTM lifestyle subgroups and myopia ( P>0.05). The risk of co-occurrence of overweight/obesity and myopia was lower in both relatively healthy group and healthy group than in the unhealthy group (relatively healthy group: HR=0.515, 95% CI: 0.348-0.763; healthy group: HR=0.571, 95% CI: 0.384-0.849). Sensitivity analyses showed this result to be stable for myopia, overweight/obesity and myopia co-morbidities. Conclusion:Persistent unhealthy lifestyle increases the risk of overweight/obesity and myopia co-occurrence in adolescents.

BACKGROUND:The clearance pathway of metabolic waste in the brain is crucial for maintaining neural homeostasis.The accumulation of metabolic waste disrupts this equilibrium,representing a common pathological feature of many central nervous system diseases.In recent years,research focusing on the glymphatic system has emerged as a hotspot in the nervous system field.OBJECTIVE:To construct a knowledge map of glymphatic system research,visually analyze the current state of research,main hotspots,and future development trends within this area.METHODS:Utilizing CiteSpace,VOSviewer,and the Bibliometrix package in the R language environment,this study conducted an in-depth visual analysis of glymphatic system-related literature from the Web of Science Core Collection database,spanning from January 2012 to March 2024.This analysis included authors,institutions,countries,journals,keywords,and co-citation frequencies.RESULTS AND CONCLUSION:A total of 687 related articles were included in this study.The number of publications in this field increased year by year,showing an explosive growth trend in the past three years.The countries,institutions,and authors with the largest number of publications in this research field were the United States,University of Rochester,and Professor Maiken Nedergaard.The journal with the highest number of publications was JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM.The high-frequent and high-central keywords mainly focused on the mechanism such as cerebrospinal fluid hydrodynamics,neurological diseases such as Alzheimer's disease,and imaging techniques such as diffusion tensor imaging.The literature with the highest co-citation frequency was a classic review of the glymphatic system.The above results show that the research of glymphatic system is an emerging and active field,which has attracted wide attention at home and abroad and gradually expand from theoretical research to clinical practice.

It is believed that patients with cirrhotic ascites exhibit a pathological mechanism characterized by the decline of healthy qi and the accumulation of pathogenic factors. Clinically， treatment should be based on the theory of tonification and purging， with a staged approach distinguishing between the active phase and the remission phase. The balance between tonification and purging should be adjusted according to the progression of pathogenic and healthy actors. In the acute phase， purging should take precedence over tonification， using purging as a means of tonification to facilitate the flow of water and qi through the triple energizer. The severity of water retention， dampness， blood stasis， and heat should be carefully assessed to ensure thorough elimination of pathogenic factors while avoiding harm to healthy qi. Medication adjustments should be made once the pathogenic factors are significantly weakened. In the remission phase， an integrated approach combining both tonification and purging should be adopted， incorporating purging within tonification to clear residual pathogens and prevent recurrence. Concurrently， proactive treatment of the underlying disease is essential to achieve complete recovery and prevent the recurrence of ascites.

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.

BACKGROUND:The clearance pathway of metabolic waste in the brain is crucial for maintaining neural homeostasis.The accumulation of metabolic waste disrupts this equilibrium,representing a common pathological feature of many central nervous system diseases.In recent years,research focusing on the glymphatic system has emerged as a hotspot in the nervous system field.OBJECTIVE:To construct a knowledge map of glymphatic system research,visually analyze the current state of research,main hotspots,and future development trends within this area.METHODS:Utilizing CiteSpace,VOSviewer,and the Bibliometrix package in the R language environment,this study conducted an in-depth visual analysis of glymphatic system-related literature from the Web of Science Core Collection database,spanning from January 2012 to March 2024.This analysis included authors,institutions,countries,journals,keywords,and co-citation frequencies.RESULTS AND CONCLUSION:A total of 687 related articles were included in this study.The number of publications in this field increased year by year,showing an explosive growth trend in the past three years.The countries,institutions,and authors with the largest number of publications in this research field were the United States,University of Rochester,and Professor Maiken Nedergaard.The journal with the highest number of publications was JOURNAL OF CEREBRAL BLOOD FLOW AND METABOLISM.The high-frequent and high-central keywords mainly focused on the mechanism such as cerebrospinal fluid hydrodynamics,neurological diseases such as Alzheimer's disease,and imaging techniques such as diffusion tensor imaging.The literature with the highest co-citation frequency was a classic review of the glymphatic system.The above results show that the research of glymphatic system is an emerging and active field,which has attracted wide attention at home and abroad and gradually expand from theoretical research to clinical practice.