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A fast, simple, and cost-effective miniaturized solid-phase extraction method using calixarenes as adsorbent was developed for the micro-extraction of cyanazine, simazine, atrazine, and propazine from complex samples. The ultrahigh-performance liquid chromatography coupled with quadrupole time-of-flight tandem mass spectrometry was employed for the structural identification of target compounds. The parameters affecting the performance of extraction, such as the type of sorbents, the amount of the sorbent, desorption solvents, breakthrough volume, and adsorption capacity, were optimized. Under optimal conditions, the linear range was 6-600 ng mL−1 with the coefficients of determination from 0.9943 to 0.9998. The limits of detection and quantification for the four triazines were 0.01-0.04 and 0.04-0.15 ng mL−1, respectively. The proposed method was successfully used to determine triazine herbicides in the honey and milk samples. [ABSTRACT FROM AUTHOR]

Aim: This cross-sectional study was designed to characterize by age the ratios of limb segments length to height and extremities-trunk ratio and body proportions of southern Chinese children.Methods: Data were collected from students (n = 4715) from five school, aged 6-17 years, in the city of Chongqing. Their standing height, sitting height, arm span, forearm length, upper arm length, leg length, lower leg length, and ratios of extremities to trunk length were determined.Results: Sitting height, forearm length, upper arm length, arm span, and lower leg length were highly correlated with standing height (r > 0.9; P < 0.05). The ratio of extremities to trunk increased till about 13 years of age for both genders.Conclusions: The length of extremities and their ratio to sitting height reflect regular changes of growth in Chinese children as their age, and limb segments length is highly correlated with height. [ABSTRACT FROM AUTHOR]