A novel method for accurate,fast and sensitive detection of pesticides such as imidacloprid,isocarbophos,phoxim,dursban,imidacloprid,pyridaben and avermectin in environmental water samples has been developed by using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) coupled with high performance liquid chromatography with ultraviolet detection (HPLC-UV).The UA-DLLME parameters such as types/volumes of extraction/dispersion solvents,ultrasonic time,ionic strength and extraction time were investigated.Under the optimized extraction conditions,the linearity for the detection of six pesticides in the concentration range of 10-600 μg/L was obtained with limits of detections (LODs) of 0.8-3.1 μg/L and relative standard deviations (RSDs) of 4.7％-11.3％.UA-DLLME method exhibited strong enrichment ability for the six pesticides,and the enrichment factor (EFs) were ranged from 58 to 187.This method had perfect linearity,precision and recovery results,and showed obvious advantages and practicality comparing the previously reported methods.

Objective: To compare the safety and immunogenicity of two different sequential schedules of inactivated poliomyelitis vaccine made from Sabin strain (sIPV) followed by typeⅠ+Ⅲ bivalent oral poliovirus vaccine (bOPV) in Drug Candy (DC) form or liquid dosage form). Methods: This randomized, blinded, single center, parallel-group controlled trial was done from September 2015 to June 2016 in Liuzhou, Guangxi province. Healthy infants aged ≥2 months were eligible for enrollment and divided into 1sIPV+2bOPV or 2sIPV+1bOPV sequential schedules. According to the bOPV dosage form each sequential schedules, the subjects again were divided into drug candy(DC) form or liquid dosage form group, being 1sIPV+bOPV (DC)/1sIPV+2bOPV(liquid)/2sIPV+1bOPV(DC)/2sIPV+1bOPV(liquid). According to 0, 28, 56 d immunization schedule, Each group were given 3 doses. We recorded adverse events during the clinical trial (399 participants who receive at least one dose). 28 days post-Dose 3, we receive a total of 350 blood samples (excluding the quitters or subjects against trial plan), using cell culture trace against polio virus neutralization test Ⅰ, Ⅱ, Ⅲ neutralizing antibody (GMT), calculating the antibody positive rate.PolioⅠ,Ⅱand Ⅲ antibody titers were assessed by virus-neutralizing antibody assay and the seroconversion (4-fold increase in titer) from pre-Dose 1 to 28 days post-Dose 3 was calculated (total 350 samples) . Results: During the vaccination, the incidence of AEs in 1sIPV+2bOPV(DC), 1sIPV+2bOPV (liquid), 2sIPV+1bOPV(DC), 2sIPV+1bOPV (liquid) group were 79%, 76%, 80% and 74% (χ²=1.23, P=0.747) , respectively. The severe AEs in groups were 6%, 5%, 6% and 4% (χ²=0.57, P=0.903) , respectively, and none was considered to be vaccination related. 28 days after 3^rd vaccination, the seroconversion rates in 1sIPV+2bOPV (DC), 1sIPV+2bOPV (liquid), 2sIPV+1bOPV (DC), 2sIPV+1bOPV (liquid) group, were 99%, 100%, 99% and 99% (χ²=0.94, P=0.815) , respectively, for type Ⅰ poliovirus; and 47%, 57%, 80%, 79% (χ²=31.56, P<0.001) , respectively, for type Ⅱ; and were 100%, 99%, 100%, 99% (χ²=2.02, P=0.568) , respectively, for type Ⅲ. In each group, the GMT of antibody against poliovirus typeⅠ were 4 539.68, 6 243.43, 6 819.53 and 7 916.29 (F=25.87, P<0.001) , respectively; Type Ⅱ were 12.98, 10.54, 63.75 and 84.21 (F=8.68, P=0.034) , respectively; Type Ⅲ were 1 172.55, 1 416.03, 2 648.89 and 3 250.75 (F=14.50, P=0.002) , respectively. Conclusion On the same sequential schedules, there was no significant difference between the dosage forms, all of them showed good safety and immunogenicity. In the same dosage forms with different sequential schedules, the seroconversion rate was higher in 2 dose sIPV group than the 1 dose sIPV group, especially at the neutralizing antibody GMT level against polio type Ⅱ and Ⅲ after vaccination.