Objective:To develop the screening checklist of brief interview for autism disorder suitable for Chinese children and evaluate its reliability and validity.Methods:Based on existed research results and diagnostic criteria for autism spectrum disorder of DSM-5, the screening checklist of brief interview for autism spectrum disorder(SCAD) was developed. A sample of 238 children were selected for investigation and 28 of them were retested for test-retest reliability with 2-4 weeks interval. Cronbach's α coefficient, split-half correlation coefficient, test-retest reliability, and evaluator consistency were used to test the reliability of the scale. Content validity, construct validity and empirical validity were used to test the validity of the scale.All statistical analysis were conducted by SPSS 22.0 and AMOS 17.0.Results:The SCAD contains two components and six dimensions, with a total of 25 items. The Cronbach's α coefficient was 0.936 for the total scale and were 0.938, 0.771 for the two components. The split-half coefficient for the total scale and the two components were 0.962, 0.938 and 0.794. The test-retest reliability for the total scale and the two components were 0.806, 0.795 and 0.766. The Kendall coefficient for the total scale and the two components were 0.968, 0.982 and 0.950. The SCAD item-level content validity index (I-CVI) ranged from 0.66 to 0.98 and the Kappa value ranged from 0.66 to 0.98. The scale-level content validity S-CVI/UA and S-CVI/Ave were 0.89 and 0.94. The correlations between SCAD and calibration tests such as ABC, CARS and M-CHAT were 0.54, 0.53 and 0.87, and the correlation coefficients with the M-CHAT-R/F between the two components were 0.87 and 0.76 respectively (both P<0.01). The result of CFA demonstrated that the model fitted the data with well construct validity(χ 2/ df=0.910, RMR=0.049, AGFI=0.974, RMSEA=0.010, PNFI=0.530, PCFI=0.533, NFI=0.994, RFI=0.988, CFI=1.000). The correlation coefficient of the two components was 0.88 and that with the total scale were 0.97 and 0.90, each dimensions with the total scale ranged from 0.72 to 0.93. Conclusion:The SCAD has a good reliability and validity, and it can be used as a clinical screening tool for children with autism spectrum disorder.

Objective To investigate the solubility and stability of Tetrodotoxin (TTX) in different solvents, and the effect of temperature and pH on its stability. Methods Solutions of TTX in different matrices were prepared. Their concentrations at different temperatures and pH buffers were determined by high performance liquid chromatography and their solubility and stability were analyzed and calculated. Results TTX was most soluble at pH 3.5 and its solubility decreased as the pH increased. TTX degraded most rapidly under strong alkali conditions, with complete degradation after 20 min of reaction at 0.1 mol/L sodium hydroxide and 70 ℃. The stability test results similarly demonstrated that TTX was least stable under alkaline conditions. In a PBS buffered solution at 37 ℃, pH 7.4, TTX concentration began to decrease consistently at 1~10h, with a degradation rate of 88.07±0.27% after 28 days. Conclusion TTX is readily soluble in acidic aqueous solutions at pH 3.5 and almost insoluble in alkaline aqueous solutions. Its stability is closely related to the temperature and pH of the medium. It is more stable in acidic aqueous solutions and easily degrades under alkaline conditions, and its degradation process could be accelerated by increasing temperature.