ABSTRACT
Objective@#To explore the mediating effects of adolescent loneliness and depressive symptoms on interparental conflict and adolescent non-suicidal self-injury, so as to provide insights into the prevention and interventions of adolescent non-suicidal self-injury.@*Methods@#Students from 7 middle schools in Tianjin, Henan, Sichuan, Zhejiang and Inner Mongolia were selected using convenient sampling method. Their loneliness, depressive symptoms and non-suicidal self-injury occurrence were investigated using the Three-Item Loneliness Scale, the Center for Epidemiological Studies Depression Scale and Non-Suicidal Self-injury Scale, and interparental conflict was evaluated by adolescents and their mothers respectively, using the adolescence revision of Co-parenting Scale and the Co-parenting Relationship Scale. The mediating effects of loneliness and depressive symptoms on interparental conflict and non-suicidal self-injury was examined using a structural-equation model.@*Results@#A total of 544 students were recruited, with a mean age of (14.19±; 1.43) years. There were 241 males (44.30%) and 303 females (55.70%); 452 junior high school students (83.10%), 46 high school students (8.45%) and 46 vocational high school students (8.45%); and 150 students with non-suicidal self-injury (27.57%). The scores of loneliness, depressive symptoms, parental conflict evaluated by students and their mothers were (4.38±; 1.87), (7.32±; 6.06), (14.10±; 8.03) and (3.04±; 3.19), respectively. The results of structural equation model analysis showed that parental conflict had no direct effect on non-suicidal self-injury, but loneliness (β=0.074, 95%CI: 0.038-0.114) and depressive symptoms (β=0.096, 95%CI: 0.061-0.136) played indirect effects on interparental conflict and non-suicidal self-injury, and they also exerted a chain mediating effect (β=0.064, 95%CI: 0.037-0.095) (all P<; 0.05).@*Conclusion@#Interparental conflict can impact adolescent non-suicidal self-injury through the mediating effects of adolescent loneliness and depressive symptoms.
ABSTRACT
ABSTRACT A simple and sensitive method for simultaneous determination of furan and vinyl acetate (VA) in vapor phase of mainstream cigarette smoke with cold trap and gas chromatography-mass spectrometry (GC-MS) was developed. A Cambridge filter pad (CFP) was placed in front of the impingers of smoking machine to remove the particle phase from cigarette smoke. Furan and VA in vapor phase of mainstream cigarette smoke were collected in two impingers connected in series by filled with methanol at -78°C. The solutions were added with deuterium-labeled furan-d4 and VA-d6 as internal standards and analyzed by GC-MS. The results showed that the calibration curves for furan and VA were linear (r2 > 0.9995) over the studied concentration range. The intra- and inter-day precision values for furan and VA were <7.07% and <9.62%, respectively. The extraction recoveries of furan and VA were in the range of 94.5-97.7% and 92.3-94.9%, respectively. Moreover, the limits of detection for furan and VA were 0.028 µg mL-1 and 1.3 ng mL-1, respectively. The validated method has been successfully applied to determine the emissions of furan and VA in the vapor phase of mainstream cigarette smoke under International Organization for Standardization (ISO) and Canadian Intense (CI) smoking regimen.