Objective:To investigate the prevalence and influencing factors of mental health status and internet-surfing behavior among rural adolescents in Sichuan province,and explore the mutual effects between mental health status and internet-surfing behavior.Methods:Totally 2745 junior and senior high school students of grade seven and grade ten from two rural schools were selected.Mental health status,self-esteem and social support of students were assessed with Mental Health Inventory of Middle-school students (MMHI),Rosenberg self-esteem scale (SES) and social support rating scale (SSRS) respectively.Demographic characteristics,internet-surfing behavior were obtained using cross-sectional survey.Non-recursive structural equation model was applied to analyze the effects of other variables on mental health status and internet-surfing behavior and the mutual effects between them.Results:The mean score of MMHIwas (2.1 ±0.7),and the dimensions including academic stress (2.4 ±0.9),emotional instability (2.4 ±0.8) and anxiety (2.4 ± 1.0) got the top three.The total prevalence of long-time internet-surfing was 32.8％ (899/2745).The structural equation model showed that female and increasing age had positive effects on score of MMHI (β =0.058,0.058,P ＜ 0.001),and male and increasing age positively influenced internet-surfing behavior (β =-0.171,0.149,P ＜ 0.001).The scores of SES and S SRS were directly negatively related to the score of MMHI (β =-0.300,-0.263,P ＜ 0.001),and indirectly negatively affect internetsurfing behavior through the mediating effect of mental health (βi =-0.074,-0.065,P ＜ 0.010).The score of MMHI had positively effects on long-time internet-surfing behavior (β =0.246,P ＜ 0.001),and long-time internetsurfing behavior had positively effects on the score of MMHI in reverse (β =0.008,P ＜ 0.001),but much weaker.Conclusion:There are mild mental health problem among rural adolescents,and internet-surfing behaviors are prevalent among this population.Poor mental health and long-time internet-surfing behavior are risk factors mutually.

ObjectiveTo understand the current situation of tobacco use among rural adolescents in Sichuan Province and its influencing factors， to explore the relationship between smoking behavior and psychosocial influencing factors of rural adolescents in Sichuan Province， and to provide a scientific basis for the prevention and control of smoking among rural adolescents. MethodsAn "Adolescent Health Questionnaire" was used as the survey tool to investigate 2 671 students in the 8th and 11th grades of two township middle schools in Zizhong County， Sichuan Province. The structural equation model in Mplus 7.0 was used to analyze the relationship between adolescent tobacco use behavior， mental health， and life satisfaction. ResultsAmong the surveyed adolescents， 28.3% （756/2 671） had tried tobacco products， and 9.5% （255/2 671） had used tobacco products in the past 30 days. The prevalence of tobacco use was higher among boys （16.6%） than girls （3.5%）， and among 11th grade students （21.9%） compared to 8th grade students （7.3%）， with statistically significant differences （χ²=131.99 and 4.24， both P<0.05）. The current tobacco use rate increased with the increase in monthly allowance （χ²=46.96， P<0.05）. The structural equation model of smoking behavior showed that mental health had a positive and direct impact on smoking behavior， and an indirect impact on smoking behavior through living environment satisfaction. Living environment satisfaction had a negative and direct impact on smoking behavior with the mediating effect accounting for 19.2% of the total effect. The non-standardized mediating effect of mental health on smoking behavior through life environment satisfaction and its 95%CI were 0.007 （0.002‒0.012）. ConclusionAdolescent smoking behavior is a complex psychosocial behavior， and the situation of adolescent tobacco use in rural areas in Sichuan is severe. There is a correlation between adolescent tobacco use behavior and psychosocial influencing factors. Psychosocial influencing factors can predict adolescents’ tobacco use behavior. Attention should be paid to the important role of psychosocial influencing factors when intervening in rural adolescents’ smoking behavior.

Objective To investigate the prevalence of nosocomial infection among inpatients in a tertiary hospital， and provide scientific evidence for hospital infection control and targeted surveillance. Methods A cross-sectional survey was conducted to investigate a total of 543 hospitalized patients using the hospital information system. Results The prevalence of hospital-acquired infection （HAI） was 4.24%， and that of community-acquired infection （CAI） was 23.39%. HAI prevalence differed significantly among the departments （ χ ²=148.870， P <0.05）， and was highest in the department of intensive care medicine （72.73%）. Sites of infection were significantly different between HAI and CAI （ χ ²=22.942， P =0.011）； however， the most frequent site of infection was lower respiratory tract in both HAI and CAI. Major pathogens for nosocomial infection were Gram-negative bacteria （56.92%）， mainly Escherichia coli and Klebsiella pneumoniae . Antimicrobial usage was observed in 31.68% of the patients， principally for therapeutic use of antibacterial drugs （80.23%） and a combination of drugs （88.95%）. Examination rate of pathogens following the antimicrobial usage was 72.08%. Conclusion The investigation on the prevalence of nosocomial infection may facilitate fully understanding the nosocomial infection. It warrants strengthening the monitoring in the departments of intensive care medicine and on multi-resistant bacteria， and achieving antimicrobial stewardship， so as to improve the awareness of hospital infection control in medical staff' and effectively reduce the occurrence of nosocomial infection.