Résumé
OBJECTIVE: To establish a headspace gas chromatography-mass spectrometry method for the determination of 14 chlorinated hydrocarbons in urine. METHODS: The urine sample 4.00 mL and anhydrous sodium sulfate 3.00 g were added into a 10.00 mL headspace bottle, then the headspace bottle was maintained at 70 ℃ for 40.0 min. After headspace pretreatment, 14 chlorinated hydrocarbons in headspace air were separated in the DB-5 MS capillary column of the gas chromatography and detected by mass spectrometer. RESULTS: There was a good linear relationship of 14 chlorinated hydrocarbons in urine in the range of 0.62-1 630.00 μg/L. The linear correlation coefficient was greater than 0.999 0.The minimum detectable concentration was 0.19-0.43 μg/L and the minimum quantitative concentration was 0.62-1.44 μg/L. The average recovery rate was 89.8%-107.1%. The within-run relative standard deviation(RSD) was 4.0%-8.5% and the between-run RSD was 6.3%-9.1%. Urine samples can be stored at 4 ℃ or-8 ℃ for 3 days and below-20 ℃ for 7 days. CONCLUSION: This method is rapid, simple, sensitive, accurate and has little interference,which can be used as a method for detecting 14 kinds of chlorinated hydrocarbons in urine samples of patients with occupational poisoning.
Résumé
Objective@#To investigate association between childhood abuse and self-esteem among children in Sichuan.@*Methods@#A total of 700 students aged 10-16 years from four cities of Sichuan were selected through stratified random sampling method. All the participants were investigated with Screen Questionnaire of Child Abuse(SQCA), the Self-esteem Scale (SES) and the E-Prime based Implicit-Association Test(IAT).@*Results@#The prevalence of childhood abuse in Sichuan is 11.3%(65/574). Among them, 55.4% reported one type of abuse experience, 29.2% reported two types and 15.4% reported 3 or more types of abusive experiences. The average level of explicit self-esteem for the total sample children (x〖TX-*3〗=28.92, higher than 26) was in the medium level. For children with abuse experiences, explicit (t=-2.56, P<0.05) and implicit self-esteem (t=-2.40, P<0.05) was significantly lower than average level of the total sample. Educational background of primary caregivers was positively associated with explicit self-esteem(P<0.05). Gender and childhood abuse entered in the final regression model for implicit self-esteem(F=6.11, P<0.01), and childhood abuse negatively correlated with implicit self-esteem(t=-2.83, P<0.01).@*Conclusion@#Children with abuse experiences are more likely to have low implicit self-esteem.
Résumé
OBJECTIVE: To establish a method for simultaneous detection of five kinds of olefine chlorides in workplace air by solvent desorption-gas chromatography. METHODS: The olefine chlorides in workplace air were collected using activated charcoal tubes,desorbed by carbon disulfide,separated on a HP-INNOWAX capillary column and detected with flame ionization detector. RESULTS: The linear range of the five kinds of chlorinated olefins( vinyl chloride,allyl chloride,chloroprene,trans-1, 2-dichloroethylene, cis-1, 2-dichloroethene) was wide and the linear correlation coefficient was greater than 0. 999 8. The detection limit and the minimum detectable concentrations were 0. 30-0. 80 mg/L and 0. 05-0. 13 mg/m~3,respectively( air sample volume 6. 0 L). The recovery rate was 95. 90%-102. 67%. The within-run and betweenrun relative standard deviations were 0. 00%-3. 74% and 0. 21%-6. 12%,respectively. The samples could be preserved at room temperature for at least 14 days. CONCLUSION: This method has simple operation,good linear range,high sensitivity and good reproducibility,which is suitable for detecting 5 kinds of olefine chlorides in workplace air.