Objective: To compare the effects of height-desk-chair matching on the viewing distance of primary school students before and after intervention, so as to provide scientific basis for the hygiene management of desks and chairs. Methods: From April to June 2025, a random cluster sampling method was used to select 141 third grade students from three classes equipped with adjustable desks and chairs in a primary school in Hefei City for a height-desk-chair matching intervention study. The height of students desks and chairs was adjusted according to the standard height and height range specified in the Functional Sizes and Technical Requirements of Chairs and Tables for Educational Institutions (GB/T 3976-2014), with an intervention period of one week. Before and after the intervention, eye use data were measured by using the electronic smart device "Cloud Clip", while collecting data on vision data viewing distance, time spent using eyes at close range and outdoor time, desk and chair height, and physical examination. Linear regression analysis was used to investigate the factors related to viewing distance before the intervention of height-desk-chair matching, and a paired t-test was used to analyze the difference in viewing distance before and after the intervention. A mixed effects model was used to explore the effect of height desk and chair adaptation intervention on viewing distance. Results: The compliance rates for desk and chair adjustments before and after the intervention were 1.4% and 18.4%, respectively, with a statistically significant difference ( χ 2=22.84, P <0.01). The viewing distance increased from (30.48±5.01) cm before intervention to (32.06±5.75) cm post intervention, with a statistically significant difference ( t=4.57, P <0.01). The proportion of students meeting the viewing distance standard increased from 33.3% to 51.1%. The linear mixedeffects model results indicated that the association between height appropriate desk and chair interventions and viewing distance was statistically significant, regardless of whether covariates such as time spent using eyes at close range and outdoor time were adjusted ( β=-1.58, 95%CI = -2.25 to -0.91; β=-1.14, 95%CI =-1.85 to -0.43, both P <0.05). Conclusion Height adjusted desks and chairs, which can effectively increase the viewing distance for primary school students, has positive implications for improving healthy eye care behaviors among children and adolescents.

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 analyze the quantity transfer rule in the processing of Astragalus membranaceus before and after moistening-soaking and steaming-soaking followed by cutting. METHODS Three batches of A. membranaceus decoction pieces processed through moistening-soaking and steaming-soaking followed by cutting were prepared. The HPLC overlapping fingerprints of A. membranaceus and its decoction pieces were established through the Similarity Evaluation System of Chromatographic Fingerprints of TCM （2012 edition）. Combined with the previous qualitative analysis results， the common peaks were identified， the changes of common peak area were analyzed， and the principal component analysis was carried out. The contents of calycosin-7-glucoside， astragaloside Ⅰ and astragaloside Ⅳ in A. membranaceus and its decoction pieces were determined by HPLC， and the content differences of each component in different samples were compared. RESULTS The results of fingerprint analysis showed that 17 common peaks were identified. After steaming-soaking and moistening-soaking of A. membranaceus， the proportion of common peak area in the decoction pieces changed compared with the original medicine （for example， in A. membranaceus steaming-soaking decoction pieces， the proportion of peak area of malonyl calycosin-7-glucoside and malonyl astragaloside Ⅰ decreased， while the proportion of peak area of calycosin-7-glucoside increased）. The results of principal component analysis showed that A. membranaceus， and its decoction pieces after moistening-soaking and steaming-soaking followed by cutting were all clustered into one category respectively. The results of content determination showed that， compared with A. membranaceus， the average content of calycosin-7-glucoside in A. membranaceus moistening-soaking decoction pieces was significantly reduced （P＜0.05）； the average contents of calycosin-7-glucoside and astragaloside Ⅳ in A. membranaceus steaming- soaking decoction pieces were significantly increased （P＜0.05）； there was no significant difference in the average content of astragaloside Ⅳ in A. membranaceus moistening-soaking decoction pieces and astragaloside Ⅰ in the two decoction pieces （P＞ 0.05）. CONCLUSIONS There are differences in the quantity transfer rules of A. membranaceus before and after moistening-soaking and steaming-soaking followed by cutting. Steaming-soaking followed by cutting may make the transformation of unstable components （such as malonyl calycosin-7-glucoside and malonyl astragaloside Ⅰ） more complete.

Objective To understand the epidemic characteristics and genotype distribution of acute hepatitis B in Tianjin, and to find out the relationship between genotype and epidemic characteristics. Methods The information of acute hepatitis B cases with a local address in Tianjin was collected through the National Infectious Disease Surveillance System in Tianjin from 2018 to 2022. The patient outcomes were followed up through hospital system records and telephone survey, and hepatitis B virus (HBV) genotypes were detected by fluorescent PCR. Results From 2018 to 2022, there were 387 cases of acute hepatitis B with local address reported in Tianjin, with an average annual reported incidence rate of 0.52/100 000, showing a downward trend in general (χ²=28.553，P<0.001). The reported male to female incidence ratio was 1.68. The age distribution was mainly concentrated in the 30-65 age group, with the highest incidence rate (1.22/100 000) reported in the 35-39 age group. 72.87% of cases showed negative HBsAg after 6 months of follow-up following diagnosis. The proportion of cadres and staff who turned negative (92.16%) was significantly higher than that of those who did not turn negative (0%). The median ALT (1508.00 U/L) in the turning negative group was significantly higher than that in the non-turning negative group (976.00 U/L). Among 315 cases with successful genotyping, genotype C accounted for 81.27%, and genotype B accounted for 14.92%, with 47 cases. The median ALT of genotype B patients with acute hepatitis B (1585.00 U/L) was significantly higher than that of genotype C patients (988.00 U/L). Conclusion The reported incidence rate of acute hepatitis B in Tianjin is relatively low, and shows a downward trend. Young and middle-aged men are prone to infect HBV. Genotype C is the main genotype, and genotype B HBV causes more serious liver damage in patients with acute hepatitis B.

Objective: To analyze the association of participation in non-sports extracurricular tutoring classes with the prevalence of screening myopia, axial length (AL) and axial length to corneal radius ratio (AL/CR) among primary school students, so as to provide evidences for formulating myopia prevention and control policies. Methods: In December 2024, combination of convenience and cluster sampling method was used to select 2 273 students from two primary schools in Hefei City, Anhui Province. Ophthalmic examinations and questionnaire surveys were conducted to obtain information on myopia, AL, AL/CR and participation in various types of extracurricular tutoring. A binary Logistic regression model was used to analyze the association between non-sports tutoring and screening myopia, and multiple linear regression models were used to examine the associations between non-sports tutoring and AL and AL/CR. Results: Among the surveyed students, the participation rate in non-sports extracurricular tutoring classes was 64.9% , and the overall prevalence of screening myopia was 39.1%. The average AL and AL/CR were (23.60± 1.01 ) mm and (3.00±0.12), respectively. Univariate analysis showed that students who attended non-sports, music, or academic tutoring classes for ≥2 h per week had higher risks of screening myopia and greater AL/CR values than non-participants (screening myopia: OR =1.38, 1.82, 1.55; AL/CR: β =0.01, 0.03, 0.03; all P <0.05). After adjusting for sex, grade, and participation in sports tutoring, multivariate analysis indicated that participation in non-sports and musical instrument tutoring classes for ≥2 h per week remained significantly associated with higher risks of screening myopia ( OR =1.26, 1.49, both P <0.05). Multiple linear regression showed that participation in musical instrument tutoring for ≥2 h per week was positively correlated with AL ( β=0.14, P < 0.05). Conclusions Participation in non-sports extracurricular tutoring is common among primary school students. Attending non-sports tutoring classes for ≥2 h per week increases the risk of screening myopia.

BackgroundIn China， the structure shift from just one-child family to both one-child and more-than-one-child families is happening. Exploring how the sibling relationships effect between adolescent personality impulsivity and aggressivity is of great significance for promoting adolescent mental health as well as maintaining social harmony and stability. ObjectiveTo investigate the effecting path of sibling relationships between personality impulsivity and aggressivity in adolescents， so as to provide references for the prevention of violent and aggressive behavior in adolescents. MethodsFrom February to April， 2023， a total of 1 200 students with sibling relationships from 12 primary and secondary schools in a county of Sichuan province were included by random sampling. Barratt Impulsivity Scale （BIS-11）， Chinese Version of Buss & Perry Aggression Questionnaire （AQ-CV）， and Sibling Relationship Questionnaire （SRQ） were used for cross-sectional investigation. Pearson Correlation Analysis was used to analyze the correlation between the scores of these scales. Bootstrap method was used to test the effecting path of sibling relationships between personality impulsivity and aggressivity. ResultsThe total score of BIS-11 was positively correlated with that of AQ-CV as well as the scores of conflict and competition dimensions in SRQ （r=0.485、0.276、0.280，P<0.01）， while negatively correlated with the score of warmth/intimacy dimension in SRQ （r=-0.383， P<0.01）. The total score of AQ-CV was positively correlated with the scores of conflict and competition dimensions in SRQ （r=0.387， 0.340， P<0.01）， while negatively correlated with the score of warmth/intimacy dimension in SRQ （r=-0.304， P<0.01）. Within SRQ， negative correlations could be observed between the score of warmth/intimacy and scores of conflict and competition （r=-0.307， -0.375， P<0.01）， whereas positive correlation could be observed between the score of conflict and that of competition （r=0.267， P<0.01）. The total effect of personality impulsivity level on aggressivity level in adolescent was 0.480 （P<0.01）. Sibling relationships played a mediating role between personality impulsivity and aggressivity in adolescents. Meanwhile， the indirect effect values of warmth/intimacy， conflict and competition were 0.054， 0.075 and 0.062， with the effect values accounting for 11.21%， 15.70% and 12.93%， respectively. ConclusionThe personality impulsivity of adolescents can directly affect their aggressivity， and sibling relationships may act as an important channel connecting personality impulsivity and aggressivity. ［Funded by 2023 Project of the Psychology and Behavioral Science Research Center of the Deyang Federation of Social Sciences （number， XLYXW2023305）］

Objective:To investigate the clinical outcomes of using autologous mandibular outer cortex "sandwich" grafting to augment mandible for correcting lower facial asymmetry with normal occlusal relationships.Methods:A retrospective analysis was conducted on the clinical data of patients with lower facial asymmetry treated at the Department of Plastic Surgery, the Affiliated Friendship Plastic Surgery Hospital of Nanjing Medical University, from January 2016 to December 2019. Preoperative cone-beam CT (CBCT) scans of the maxillofacial region were obtained to acquire three-dimensional data of the maxillofacial skeleton. Computer-aided design was used to determine the osteotomy range of the mandibular outer cortex and design osteotomy guide template. The outer cortex of the larger mandibular side (donor site) was harvested according to the osteotomy guide template and sectioned. The segmented mandibular outer cortex was then contoured to match the arc of the recipient side’s mandibular outer cortex and fixed to the inner side of the recipient mandibular outer cortex, thus increasing the width and thickness of the expanded mandible. Follow-up was conducted at 7th day and 6 months postoperatively, CBCT scan was performed to measure the changes in ramus height (Co-Go), mandibular body length (Go-Me), and mandibular outer cortex thickness, and volume, and the patient satisfaction with facial appearance (1 to 5 points, with higher scores indicating higher satisfaction), were assessed to evaluate surgical outcomes. Statistical analysis was performed using SPSS 12.0 software. Paired t-tests were used to compare patient satisfaction scores preoperatively and six months postoperatively. Repeated measurement ANOVA was used to compare Co-Go and Go-Me measurements preoperatively, 7th day, and 6 months postoperatively. If a statistically significant difference is found, further analysis using post-hoc testing(Tukey’s HSD test) will be conducted to examine the data. Results:Sixteen patients with lower facial asymmetry were included, comprising of 5 males and 11 females, aged 18 to 40 years, with an average age of 25.2 years. Surgical method included contralateral mandibular outer cortex "sandwich" grafting to the expanded mandible in 9 cases and simultaneous genioplasty in 7 cases. Follow-up ranged from 6 months to 5 years, with an average follow-up of 18.6 months. All patients experienced numbness of the lower lip postoperatively, which resolved within six months, and no severe complications occurred. The symmetry of lower facial contour improved significantly and remained stable. Patient satisfaction score for facial appearance increased from (1.63±0.62) points preoperatively to (4.19±0.75) points six months postoperatively( P<0.01). The differences in Co-Go on the donor side and Go-Me on the recipient side across the three time points(preoperatively, 7th day and 6 months postoperatively) were not statistically significant(all P>0.05). However, the differences in Go-Me on the donor side and Co-Go on the recipient side across the three time points were statistically significant(all P<0.05). On the donor side, the mandibular outer cortex thickness decreased by a maximum of 6 mm on 7th day postoperatively and increased by a maximum of 2 mm at 6 months postoperatively compared to 7th day. On the recipient side, mandibular outer cortex thickness increased by a maximum of 6 mm on 7th day postoperatively and decreased by a maximum of 2 mm at six months postoperatively compared to 7th day. The volume of the mandibular outer cortex on the recipient side increased by (4 415.94±1 017.21)mm 3 at 7th day postoperatively compared to preoperatively, and decreased by (202.63±300.85)mm 3 at 6 months postoperatively. Conclusion:For lower facial asymmetrical with normal occlusal relationships and no occlusal plane deviation, contralateral mandibular outer cortex "sandwich" bone grafting can effectively increase the width and volume of the mandible on the grafted side, achieving favorable clinical outcomes.

Objective:To investigate the clinical outcomes of using autologous mandibular outer cortex "sandwich" grafting to augment mandible for correcting lower facial asymmetry with normal occlusal relationships.Methods:A retrospective analysis was conducted on the clinical data of patients with lower facial asymmetry treated at the Department of Plastic Surgery, the Affiliated Friendship Plastic Surgery Hospital of Nanjing Medical University, from January 2016 to December 2019. Preoperative cone-beam CT (CBCT) scans of the maxillofacial region were obtained to acquire three-dimensional data of the maxillofacial skeleton. Computer-aided design was used to determine the osteotomy range of the mandibular outer cortex and design osteotomy guide template. The outer cortex of the larger mandibular side (donor site) was harvested according to the osteotomy guide template and sectioned. The segmented mandibular outer cortex was then contoured to match the arc of the recipient side’s mandibular outer cortex and fixed to the inner side of the recipient mandibular outer cortex, thus increasing the width and thickness of the expanded mandible. Follow-up was conducted at 7th day and 6 months postoperatively, CBCT scan was performed to measure the changes in ramus height (Co-Go), mandibular body length (Go-Me), and mandibular outer cortex thickness, and volume, and the patient satisfaction with facial appearance (1 to 5 points, with higher scores indicating higher satisfaction), were assessed to evaluate surgical outcomes. Statistical analysis was performed using SPSS 12.0 software. Paired t-tests were used to compare patient satisfaction scores preoperatively and six months postoperatively. Repeated measurement ANOVA was used to compare Co-Go and Go-Me measurements preoperatively, 7th day, and 6 months postoperatively. If a statistically significant difference is found, further analysis using post-hoc testing(Tukey’s HSD test) will be conducted to examine the data. Results:Sixteen patients with lower facial asymmetry were included, comprising of 5 males and 11 females, aged 18 to 40 years, with an average age of 25.2 years. Surgical method included contralateral mandibular outer cortex "sandwich" grafting to the expanded mandible in 9 cases and simultaneous genioplasty in 7 cases. Follow-up ranged from 6 months to 5 years, with an average follow-up of 18.6 months. All patients experienced numbness of the lower lip postoperatively, which resolved within six months, and no severe complications occurred. The symmetry of lower facial contour improved significantly and remained stable. Patient satisfaction score for facial appearance increased from (1.63±0.62) points preoperatively to (4.19±0.75) points six months postoperatively( P<0.01). The differences in Co-Go on the donor side and Go-Me on the recipient side across the three time points(preoperatively, 7th day and 6 months postoperatively) were not statistically significant(all P>0.05). However, the differences in Go-Me on the donor side and Co-Go on the recipient side across the three time points were statistically significant(all P<0.05). On the donor side, the mandibular outer cortex thickness decreased by a maximum of 6 mm on 7th day postoperatively and increased by a maximum of 2 mm at 6 months postoperatively compared to 7th day. On the recipient side, mandibular outer cortex thickness increased by a maximum of 6 mm on 7th day postoperatively and decreased by a maximum of 2 mm at six months postoperatively compared to 7th day. The volume of the mandibular outer cortex on the recipient side increased by (4 415.94±1 017.21)mm 3 at 7th day postoperatively compared to preoperatively, and decreased by (202.63±300.85)mm 3 at 6 months postoperatively. Conclusion:For lower facial asymmetrical with normal occlusal relationships and no occlusal plane deviation, contralateral mandibular outer cortex "sandwich" bone grafting can effectively increase the width and volume of the mandible on the grafted side, achieving favorable clinical outcomes.

Objective To retrospectively analyze of factors influencing early preterm birth(EPB)and late preterm birth(LPB)in pregnancy women with placenta previa complicated by placenta accreta spectrum disorders(PAS),and assess maternal and infant outcomes.Methods We included 590 cases of pregnancy women with placenta previa complicated by PAS who underwent cesarean sections at five hospitals in Wuhan and Xianning cities between January 2018 and June 2021.These patients were divided into three groups based on delivery gesta-tional age:EPB,LPB,and term birth(TB).A multiple logistic regression model was employed to analyze the risk factors associated with EPB and LPB.Additionally,differences in early maternal and infant outcomes among these groups were examined.Results Among 590 pregnancy women with placenta previa complicated by PAS,the proportions of EPB and LPB were 9.7%and 54.4%.The use of uterine contraction inhibitors prior to cesarean section,vaginal bleeding,and previous cesarean sections history were identified as risk factors for both EPB and LPB.The proportion of severe postpartum hemorrhage was comparable between the EPB group and the LPB group;however,the incidence of neonatal asphyxia,low birth weight infants,and the rate of newborns transferred to the Neonatal Intensive Care Unit(NICU)within 24 hours after cesarean delivery were significantly higher in the EPB group compared to the LPB group.Conclusions Placenta previa complicated by PAS predominantly leads to LPB.The history of prior cesarean sections,uterine contractions,and vaginal bleeding prior to cesarean section,are sig-nificantly associated with both EPB and LPB.During the perinatal period,efforts should be made to extend gesta-tional weeks under close monitoring to minimize the incidence of premature births and thereby improve early mater-nal and infant outcomes.

Objective To investigate the characteristics of fragmented QRS waves and their correlation with ventricular ar-rhythmias in coronary heart disease patients during treadmill exercise tests.Methods A total of 216 patients suspected of hav-ing coronary heart disease or clinically diagnosed at our hospital from November 2021 to October 2022 were selected for the study.The general clinical data,cardiac ultrasound indices,laboratory indices and ECG parameters of the subjects were collect-ed.The patients were divided into two groups according to the results of coronary angiography:coronary heart disease(CHD)group(n=152)and non-CHD group(n=64).According to the presence of the fQRS wave in the treadmill exercise test,the CHD group and non-CHD group were divided into the QRS group(without the fQRS wave)and the fQRS group(with the fQRS wave).For patients with confirmed CHD,the occurrence of ventricular arrhythmia within 12 months was observed,and the CHD group was divided into a ventricular arrhythmia group(n=80)and non-ventricular arrhythmia group(n=72).ROC curves were used to analyze the diagnostic efficacy of the fQRS wave in the exercise treadmill test for CHD.A logistic regres-sion model adjusted for confounding variables was used to explore the relationship between fQRS wave duration and the risk of ventricular arrhythmias in patients with CHD.Random forest algorithm was used to screen the possible influencing factors of ventricular arrhythmias,and the formula for predicting ventricular arrhythmia events was obtained according to the regression e-quation y=1-1/(1+e-x).Bootstrap method was used to verify the prediction model.Results In the exercise treadmill test,the incidence of fQRS wave in the CHD group(116/152,76.32％)was significantly higher than that in the non-CHD group(21/64,32.81％).In the exercise treadmill test,the maximum area under the ROC curve(AUC)of the fQRS wave for CHD was 0.899(P＜0.05),the sensitivity and specificity were 94.3％and 78.2％,respectively,and the Youden index was 0.725.In the CHD group,the duration of the QRS wave and fQRS wave after exercise was significantly longer than that before exercise,and the time limit of the fQRS wave before and after exercise was significantly longer than that of the QRS wave(P＜0.05).Compared with those of the QRS group,the proportions of two-vessel and multi-vessel lesions of the fQRS group were greater,and the proportions of severe stenosis and complete occlusion were greater than those of the QRS group.The Gensini score of the fQRS group was greater than that of the QRS group.In the exercise treadmill test,the duration of the fQRS group before and after ex-ercise was positively correlated with the Gensini score.In the CHD group,the incidence of ventricular arrhythmias in the fQRS group(77/116,66.38％)was significantly higher than that in the QRS group(3/36,8.33％).The duration of the fQRS wave be-fore and after exercise was positively correlated with the risk of ventricular arrhythmia in patients with CHD.Conclusion The incidence of fQRS waves is significantly increased,and the duration of fQRS waves is significantly prolonged in patients with CHD during the treadmill exercise test.The fQRS wave has a certain value in predicting the degree of CHD and CAD.The fQRS wave and its duration in the exercise treadmill test are positively correlated with the risk of ventricular arrhythmia in pa-tients with CHD.