Objective: To understand the moderating effect of cohabitation with parents on the association between peer dating behavior and sexual behaviors among secondary vocational school students, so as to provide a scientific basis for preventing sexual behaviors among secondary vocational school students. Methods: From March to April 2021, an electronic questionnaire survey was conducted among 3 180 students from 6 vocational schools in Shanghai (urban, suburban, exurban) and Shaanxi (Shangluo, Ankang, Baoji) using cluster sampling. Spearman correlation analysis was used to investigate the relationship of cohabitation with parents, peer dating behavior and sexual behaviors among secondary vocational school students. Binary Logistic regression analysis was performed to investigate the role of cohabitation with parents on peer dating behavior and sexual behaviors among secondary vocational students. Results: There was a significant negative between cohabitation with parents and sexual ( r =-0.04); and there was a positive correlation between peer dating behavior and sexual behaviors ( r =0.24), as well as cohabitation with parents and peer dating behavior ( r =0.04)( P <0.05). Multivariable Logistic regression analysis showed an association between peer dating behavior and the occurrence of sexual behaviors ( OR=2.79-12.95, P <0.05). Cohabitation with parents played a moderating role in the association between peer dating behavior and sexual behaviors, and a signification interaction was found between cohabitation with parents and reporting that a small part or about half of their peers had dating behavior ( OR =0.48, P <0.05). Conclusions The more peers dating behavior are associated with a higher risk of sexual behaviors among secondary vocational school students, and cohabitation with parents can partly reduce this risk. School and family sexuality education for secondary vocational students should be strengthened to improve their interpersonal skills and decision-making, and ability to resist peer pressure, so as to reduce their risk of sexual behaviors.

Objective: To examine the association between parent-child relationships and bullying behaviors among junior high school students, and to explore the moderating effect of community cohesion, so as to provide evidences for bullying intervention strategies. Methods: From November to December 2017, a cluster sampling method was used to survey 1 589 students in grades 6- 8 from three junior high schools in Jing an District,Shanghai. Anonymous electronic questionnaires collected data on parent-child relationships, community cohesion, and bullying behaviors. Multivariate Logistic regression analyzed the associations and moderation effects. Results: The prevalence of bullying behaviors among junior high school students was 7.80%. Spearman correlation analysis revealed negative associations between both parent-child relationships ( r =-0.13) and community cohesion ( r =-0.10) with bullying behaviors, while parent-child relationships positively correlated with community cohesion ( r =0.29) (all P <0.01). Junior high school students with positive parent-child relationships and higher perceived community cohesion showed lower risks of bullying behaviors ( OR=0.51, 95%CI =0.36-0.72; OR=0.58, 95%CI =0.45-0.76), with a significant interaction effect between the two factors (all P <0.05). Conclusions Positive parent-child relationships and community cohesion are negatively associated with bullying behaviors in middle school students. Supportive family relationships help reduce bullying, while stronger community cohesion enhances the protective effect of positive parent-child relationships against bullying.

Objective: To explore the association between parent-child connectedness and romantic relationships of secondary vocational school students and the moderating effect of peers romantic behavior, providing scientific basis for family and school health education. Methods: From March to April 2021，2 426 students from six secondary vocational and technical schools in Shanghai and Shaanxi Province were selected to conduct the survey by combining convenience sampling and cluster sampling.Electronic questionnaires were used to collect data on students family characteristics,oneself and peer romantic behaviors, and parent-child bonding. The t-test was employed for inter group comparisons, and binary Logistic regression analysis was conducted to examine the relationship between parent-child bonding levels, peer romantic behavior, and the romantic behavior of secondary vocational students. Results: The mother-child connection (2.63±0.77) was higher than that of father-child connection (2.48±0.78), with statistically significant difference ( t =6.83, P <0.01). Multivariable Logistic regression showed that overall father-child connectedness was negatively associated with students romantic relationships( OR =0.86，95% CI =0.76-0.97， P =0.02)and was only associated to girls romantic relationships when stratified by gender( OR =0.79，95% CI =0.66-0.93， P =0.01). Peers romantic relationships were positively associated with students romantic relationships ( OR =3.19-5.12, all P <0.01), and there was a moderating effect of the association between maternal connectedness and boys romantic relationships ( OR =1.67, 95% CI =1.05-2.66, P =0.03). Among boys without romantic peers, mother-child connectedness was negatively associated with their romantic relationships ( OR = 0.60 , 95% CI =0.36-0.99, P <0.05). In the total sample of Shanghai and girls of Shaanxi, father-child connectedness was negatively correlated with the romantic relationships of secondary vocational school students ( OR =0.84,0.65,95% CI =0.71-1.00,0.50-0.85,both P <0.05). Peer romantic relationships exhibited a negative moderating effect on the influence of mother-child connectedness on the romantic relationships of males in Shanghai ( OR =1.91, 95% CI =1.03-3.57, P <0.05). Conclusions The father-daughter connectedness is negatively correlated with girls romantic behavior, and peer romantic behavior weakens the correlation between mother-child connectedness and boys romantic behavior. Efforts should be made to enhance the parent-child connectedness of secondary vocational students and their ability to cope with peer influence, providing proper guidance for adolescents heterosexual interactions.

Objective:To investigate the effects of 10° head up tilt bed rest (HUT) on human cardiac function via 3D speckle tracking echocardiography (3D-STE), and to study the difference in cardiac function under the submaximal exercise load between the horizontal position and 10° HUBR.Methods:Thirty young healthy volunteers were recruited as the subjects, who were randomly divided into an 10° HUT exercise group and horizontal exercise group with 15 subjects in each. Subjects in both groups were asked to ride the bicycle ergometer in the 10° HUBR position and supine position respectively. The load started with 50 W and was increased by 25 W every 3 min until it reached the maximum of 125 W. Before the exercise (resting state), 1 min after the load was increased each time, and 3 min after exercise (recovery period), the following indices were collected: ①basic cardiac function indices: heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), ②conventional cardiac ultrasound indices: left ventricular ejection fraction (LVEF), stroke volume (SV) and cardiac output (CO), ③left ventricular strain indices: global longitudinal strain (GLS), global circumferential strain (GCS), and global area strain (GAS) measured by 3D-SET. The changes of these indices in the 2 groups of subjects under different exercise loads were observed.Results:The differences in the major effect of the basic heart indices (HR, SBP and DBP), conventional cardiac ultrasound indices (LVEF, SV and CO) and left ventricular strain indices (GLS, GCS and GAS) in response to the exercise load were statistically significant ( F=194.90, 113.66, 17.19, P=0.017, 0.018, 0.001). With the increase of the exercise load, the basic heart indices and conventional cardiac ultrasound indices kept rising, the left ventricular strain indices reached the minimum under a moderate exercise load (75 W), HR, SBP and CO were higher than those of the resting state ( P<0.05 or 0.01). Both LVEF under exercise loads of 75, 100, 125 W and during recovery, and SV under exercise loads of 100, 125 W and during recovery were significantly higher than those of the resting state ( P<0.05 or 0.01), while GLS and GCS under exercise loads of 50, 75, 125 W ( P<0.05 or 0.01), and GAS under exercise loads of 50, 75 W ( P<0.01) were significantly lower. There were statistically significant differences not only in GCS across the groups ( F=4.60, P=0.026) but also in DBP due to the interactions between the grouping and exercise loads ( F=3.13, P=0.031). DBP was higher than that of the resting state when the exercise load was 125 W in both groups. Conclusions:During submaximal exercise, myocardial contractility shows sustained enhancement with the increase of the exercise load. The results of GLS, GCS and GAS indicate that myocardial strain reaches its lowest value under a moderate exercise load, suggesting that moderate exercise can be used to evaluate cardiac function via 3D-SET. Under a simulated lunar gravity of 10° HUT, there is less deformation in the short axis direction of the myocardium, indicating that GCS can be used as a sensitive indicator to detect changes in cardiac function under different gravities.

Objective To construct a prediction model for in-hospital mortality in the elderly(≥65 years)patients undergoing unsynchronous cardioversion in ICU and to evaluate its effectiveness.Methods A retrospective study was conducted on 276 elderly eligible patients in the ICU of the Ninth and the First Medical Centers of Chinese PLA General Hospital between June 2022 and August 2024.According to their clinical outcomes,they were divided into a non-in-hospital dead group(111 cases)and an in-hospital dead group(165 cases).Clinical data were collected,and pre-dictive factors for in-hospital mortality were screened.And then a nomogram prediction model was developed based on the obtained predictive factors,which was evaluated with ROC curve and deci-sion curve analyses.Results When compared to the non-in-hospital dead group,the in-hospital dead group had significantly higher heart rate,ratio of hemodialysis,and levels of alanine amin-otransferase,aspartate aminotransferase,lactate dehydrogenase,alkaline phosphatase,serum cre-atinine,blood glucose,lactate,low base excess,sequential organ failure assessment(SOFA)score,model for end-stage liver disease score,and larger proportions of ventricular fibrillation/flutter and structural heart disease induced by pulseless ventricular tachycardia,and had significantly lower Glasgow Coma Scale(GCS)(P＜0.05).Multivariate logistic regression analysis identified body temperature＞37℃(OR=0.426,95％CI:0.198-0.915,P=0.029),chronic obstructive pulmonary disease(OR=2.333,95％CI:1.217-4.473,P=0.011),GCS score(OR=0.622,95％CI:0.410-0.944,P=0.026),hemoglobin(OR=0.817,95％CI:0.715-0.934,P=0.003),lactate(OR=1.365,95％CI:1.174-1.587,P=0.000),heart rate＞100 bpm(OR=2.757,95％CI:1.397-5.441,P=0.003),and SOFA score(OR=1.112,95％CI:1.032-1.198,P=0.005)as pre-dictors of in-hospital mortality.ROC curve analysis showed an AUC value of above indicators combined together in the prediction was 0.797,with a sensitivity of 76.97％and a specificity of 65.77％.Calibration curve analysis demonstrated good consistency between predicted and observed outcomes.Decision curve analysis indicated favorable clinical utility of the model.Conclusion This study identifies independent risk factors for in-hospital mortality among elderly patients in the ICU who underwent asynchronous cardioversion.Based on these factors,a nomo-gram model is established,demonstrating good discrimination,calibration,and model fit,with high clinical applicability.

Objective To construct a prediction model for in-hospital mortality in the elderly(≥65 years)patients undergoing unsynchronous cardioversion in ICU and to evaluate its effectiveness.Methods A retrospective study was conducted on 276 elderly eligible patients in the ICU of the Ninth and the First Medical Centers of Chinese PLA General Hospital between June 2022 and August 2024.According to their clinical outcomes,they were divided into a non-in-hospital dead group(111 cases)and an in-hospital dead group(165 cases).Clinical data were collected,and pre-dictive factors for in-hospital mortality were screened.And then a nomogram prediction model was developed based on the obtained predictive factors,which was evaluated with ROC curve and deci-sion curve analyses.Results When compared to the non-in-hospital dead group,the in-hospital dead group had significantly higher heart rate,ratio of hemodialysis,and levels of alanine amin-otransferase,aspartate aminotransferase,lactate dehydrogenase,alkaline phosphatase,serum cre-atinine,blood glucose,lactate,low base excess,sequential organ failure assessment(SOFA)score,model for end-stage liver disease score,and larger proportions of ventricular fibrillation/flutter and structural heart disease induced by pulseless ventricular tachycardia,and had significantly lower Glasgow Coma Scale(GCS)(P＜0.05).Multivariate logistic regression analysis identified body temperature＞37℃(OR=0.426,95％CI:0.198-0.915,P=0.029),chronic obstructive pulmonary disease(OR=2.333,95％CI:1.217-4.473,P=0.011),GCS score(OR=0.622,95％CI:0.410-0.944,P=0.026),hemoglobin(OR=0.817,95％CI:0.715-0.934,P=0.003),lactate(OR=1.365,95％CI:1.174-1.587,P=0.000),heart rate＞100 bpm(OR=2.757,95％CI:1.397-5.441,P=0.003),and SOFA score(OR=1.112,95％CI:1.032-1.198,P=0.005)as pre-dictors of in-hospital mortality.ROC curve analysis showed an AUC value of above indicators combined together in the prediction was 0.797,with a sensitivity of 76.97％and a specificity of 65.77％.Calibration curve analysis demonstrated good consistency between predicted and observed outcomes.Decision curve analysis indicated favorable clinical utility of the model.Conclusion This study identifies independent risk factors for in-hospital mortality among elderly patients in the ICU who underwent asynchronous cardioversion.Based on these factors,a nomo-gram model is established,demonstrating good discrimination,calibration,and model fit,with high clinical applicability.

Objective:To investigate the effects of 10° head up tilt bed rest (HUT) on human cardiac function via 3D speckle tracking echocardiography (3D-STE), and to study the difference in cardiac function under the submaximal exercise load between the horizontal position and 10° HUBR.Methods:Thirty young healthy volunteers were recruited as the subjects, who were randomly divided into an 10° HUT exercise group and horizontal exercise group with 15 subjects in each. Subjects in both groups were asked to ride the bicycle ergometer in the 10° HUBR position and supine position respectively. The load started with 50 W and was increased by 25 W every 3 min until it reached the maximum of 125 W. Before the exercise (resting state), 1 min after the load was increased each time, and 3 min after exercise (recovery period), the following indices were collected: ①basic cardiac function indices: heart rate (HR), systolic blood pressure (SBP) and diastolic blood pressure (DBP), ②conventional cardiac ultrasound indices: left ventricular ejection fraction (LVEF), stroke volume (SV) and cardiac output (CO), ③left ventricular strain indices: global longitudinal strain (GLS), global circumferential strain (GCS), and global area strain (GAS) measured by 3D-SET. The changes of these indices in the 2 groups of subjects under different exercise loads were observed.Results:The differences in the major effect of the basic heart indices (HR, SBP and DBP), conventional cardiac ultrasound indices (LVEF, SV and CO) and left ventricular strain indices (GLS, GCS and GAS) in response to the exercise load were statistically significant ( F=194.90, 113.66, 17.19, P=0.017, 0.018, 0.001). With the increase of the exercise load, the basic heart indices and conventional cardiac ultrasound indices kept rising, the left ventricular strain indices reached the minimum under a moderate exercise load (75 W), HR, SBP and CO were higher than those of the resting state ( P<0.05 or 0.01). Both LVEF under exercise loads of 75, 100, 125 W and during recovery, and SV under exercise loads of 100, 125 W and during recovery were significantly higher than those of the resting state ( P<0.05 or 0.01), while GLS and GCS under exercise loads of 50, 75, 125 W ( P<0.05 or 0.01), and GAS under exercise loads of 50, 75 W ( P<0.01) were significantly lower. There were statistically significant differences not only in GCS across the groups ( F=4.60, P=0.026) but also in DBP due to the interactions between the grouping and exercise loads ( F=3.13, P=0.031). DBP was higher than that of the resting state when the exercise load was 125 W in both groups. Conclusions:During submaximal exercise, myocardial contractility shows sustained enhancement with the increase of the exercise load. The results of GLS, GCS and GAS indicate that myocardial strain reaches its lowest value under a moderate exercise load, suggesting that moderate exercise can be used to evaluate cardiac function via 3D-SET. Under a simulated lunar gravity of 10° HUT, there is less deformation in the short axis direction of the myocardium, indicating that GCS can be used as a sensitive indicator to detect changes in cardiac function under different gravities.

Objective: To understand sexual and reproductive health knowledge, access to sexuality education and associated factors among secondary vocational school students in Shanghai Municipality and Shaanxi Province, so as to provide a scientific basis for conducting sexuality educaiton in vocational schools. Methods: A crosssectional survey was conducted among 3 180 students in grades 1-3 selected by cluster sampling during April to June 2021 in six secondary vocational schools from three cities of Shanghai and Shaanxi (Shangluo, Ankang, Baoji). Participants were investigated through online questionnaire survey, inlcuding demographic characteristics, household information, sexual health at home and school, knowledge on sexual and reproductive health. Both t test and Chisquare test were used for group comparisons, and multivariate ordial Logistic regression was used to explore possible risk factors for sexual and reproductive health score in quartiles. Results: Respondents average score was (51.36±21.61), with the highest score on sexual harassment/sexual abuse (66.45±42.27) and the lowest score on reproduction and physiology (47.67±31.94) and contraception (43.85±26.81). Although significant differences were observed between two study sites, the primary source of knowledge in both sites was schools/teachers, followed by the Internet or friends; the main theme of school sexuality education was puberty development and health care (more than 80%); the most frequently reported topic between respondents and their parents in both sites was interpersonal relationships (more than 55%), and there were significant differences in the reporting rates of secondary vocational school students between the two regions(χ2=28.56，32.02，P<0.05). The results of multivariable Logistic regression analysis showed that residential area, gender, grade, registered residence, number of sexual related topics communicated with parents, number of subjects received from school sexuality education, and reported information sources from classmates/friends, books/magazines/newspapers, internet and communities were related to knowledge level of respondents (OR=1.62, 0.72, 1.20, 1.58, 2.09, 1.17, 1.18, 1.66, 1.62, 1.69, 1.22, P<0.05). Conclusions Vocational students of Shanghai and Shaanxi have poor sexual and reproductive health knowledge and limited access to school and family sexuality education. It is necessary to strengthen sexuality education for secondary vocational school students.

Objective: To explore the relationship between body image and adverse childhood experiences (ACEs) in adolescents. Methods: A total of 1 701 adolescents in grade 6-8 in three middle schools in Shanghai were selected by stratified cluster sampling, and were investigated anonymously using computer assisted self interview approach. Information including demographic characteristics, body image satisfaction, and ACEs were collected. The Chi square test and multivariate Logistic regression were used to explore the relationship between adolescent body image satisfaction and types of ACEs. Results: About 60.73% of the respondents were satisfied with their body image, with higher satisfaction among boys(66.16%) than among girls(55.13%)( χ 2= 21.70 ， P <0.01). About 79.19% of the respondents had experienced at least one ACE, and respectively 61.61%, 65.14% and 21.58 % of them had experienced abuse, neglect and family dysfunction. Multivariate Logistic regression analysis indicated that experiencing at least one ACE, abuse, neglect and family dysfunction were all related with low body image satisfaction among girls( OR =0.33- 0.57 , P <0.01), while among boys neglect,having 3 or more than 4 ACEs were found to be associated with body image satisfaction ( OR =0.54-0.64, P <0.05). The cumulative effects of ACEs on adolescent body image were observed. Conclusion Different types of ACEs are associated with body image in adolescents, ACEs have cumulative effects on adolescent body image, which shows gender differences.Screen of ACEs and improvement of family nurturing environment should be highlighted among adolescents, especially among girls.

Objective: To explore the relationship between gender role attitudes (GRA) and adolescent depression to provide evidence for the promotion of mental health among adolescents. Methods: A total of 1 549 students from grades 6 to 8 in three public middle schools in Jing an District of Shanghai were selected by stratified cluster sampling. The baseline and follow up surveys were conducted by anonymous electronic questionnaire on mobile tablets from November to December in 2017 and 2018, respectively. The GRA Scale and the Depression Scale were used to collect subjects attitudes towards traditional role assignment and power inequality between men and woman and depression in family and sexual relationships. The multivariate Generalized Estimating Equations (GEE) model was adopted to examine the relationship between GRA and depression. Results: The mean score of the GRA Scale was (2.52±0.83) and (2.29±0.86), while the score of Depression Scale was (15.92±5.08) and (16.48±5.29), in the baseline and follow up survey, respectively ( P <0.05). After controlling the covariates of age, bullied experience, body image, social cohesion, etc., the multivariate GEE model indicated traditional GRA was significantly associated with a higher risk of depression among both boys and girls ( β boys =0.38, β girls =0.41, P <0.05). Conclusion Traditional GRA may increase the risk of depression in adolescents, suggesting that cultivating a positive and equal GRA among this population group may help to prevent depression.