Study on influential factors and reference values for thyroid volume in Chinese children aged 6-12 years.

The purpose of the current study was to research the factors influencing thyroid volume (TVOL) in 6-12-year-old children and update the reference values. A cross-sectional study was carried out in iodine-sufficient areas of four provinces in China. Urine, edible salt and drinking water samples were collected from children. Children's height, weight and TVOL were measured. Ridge regression was used to screen variables for solving the multicollinearity problem. Quantile regression was used to analyse the relationship between the quantiles of TVOL and other variables. In total, 5653 children aged 6-12 years were enrolled in this study, including 2838 boys and 2815 girls. There was no significant difference in TVOL between boys and girls (P > 0·05). Spearman correlation analysis showed that total TVOL was positively correlated with age, height, weight, body surface area (BSA) and BMI, and the correlation coefficients were 0·616, 0·663, 0·669, 0·685 and 0·479, respectively. Among them, the correlation between TVOL and BSA was the strongest. According to the ridge regression results, age and BSA influenced TVOL, and the ridge regression coefficients were 0·13 and 0·94, respectively. Quantile regression further showed that age and BSA had significant influences on the whole TVOL distribution (P < 0·001). Therefore, the TVOL of children aged 6-12 years in China was mainly influenced by age and BSA, and reference values for TVOL of different genders based on age and BSA were established.

Variable step size adaptive cuckoo search optimization algorithm for phase diversity.

The phase diversity (PD) algorithm will eventually be converted into a large-scale nonlinear numerical optimization problem, so the selection of numerical optimization algorithm will directly determine the accuracy and speed of the algorithm settlement. In this paper, we introduce the cuckoo search optimization algorithm, which has the advantages of simple model, few parameters, and easy implementation, to the phase diversity algorithm. By improving the step size control factor in the original cuckoo search algorithm, we can make it have faster optimization speed for PD. In the simulation experiments, we further proved and gave a simple explanation in theory that in the case of large-scale wavefront sensing, compared to the traditional particle swarm algorithm, this improved algorithm has higher accuracy and faster convergence speed. Finally, we set up a simple experimental system and proved the effectiveness of the improved cuckoo search algorithm for PD.

[Obesity and Osteoporosis in Men Aged Above 50].

OBJECTIVES: To investigate the association between obesity and osteoporosis in men aged above 50 in Chengdu. METHODS: Male participants aged above 50 were recruited from those who visited West China Hospital of Sichuan University for health examinations. Bone mineral density was measured by MetriScan Bone Densitometry. The participants were divided into three groups according to T values: normal, osteopenia and osteoporosis. RESULTS: About 5.75% (525 cases) of the 9 135 male participants had osteoporosis. The three groups had significant different anthropometric parameters, including body mass, waist circumference, hip circumference, body mass index (BMI), waist-hip ratio (WHR), waist-height ratio (WHtR), a body shape index (ABSI), and body roundness index (BRI)( P<0.01). The participants with the highest quartile (Q4) of BMI, BRI, WHtR, WHR, ABSI, waist circumference and height had an age-adjusted odds ratios (OR) of 0.443 [95% confidence interval ( CI): 0.342-0.574), 0.580 (95% CI: 0.454-0.740), 0.587 (95% CI: 0.460-0.751), 0.664 (95% CI: 0.516-0.854], 1.369 (95% CI: 1.069-1.751), 0.634 (95% CI: 0.497-0.809), and 1.357 (95% CI: 1.047-1.758), respectively, for osteoporosis compared with those with the lowest quartile (Q1). The area under cures (AUC) of receiver operator characteristic (ROC) curve of BMI for osteoporosis was 0.606 (95% CI:0.580-0.632). CONCLUSIONS: Large body mass was negatively associated with osteoporosis in middle and old aged men. BMI is the strongest predictor of osteoporosis. Further longitudinal studies are required to verify such asscoiations.

Self-Sterilized Flexible Single-Electrode Triboelectric Nanogenerator for Energy Harvesting and Dynamic Force Sensing.

Triboelectric nanogenerators (TENGs) offer great opportunities to deploy advanced wearable electronics that integrate a power generator and smart sensor, which eliminates the associated cost and sustainability concerns. Here, an embodiment of such integrated platforms has been presented in a graphene oxide (GO) based single-electrode TENG (S-TENG). The as-designed multifunctional device could not only harvest tiny bits of mechanical energy from ambient movements with a high power density of 3.13 W·m-2 but also enable detecting dynamic force with an excellent sensitivity of about 388 µA·MPa-1. Because of the two-dimensional nanostructure and excellent surface properties, the GO-based S-TENG shows sensitive force detection and sound antimicrobial activity in comparison with conventional poly(tetrafluoroethylene) (PTFE) electrodes. This technology offers great applicability prospects in portable/wearable electronics, micro/nanoelectromechanical devices, and self-powered sensors.

Piezotronic Effect Enhanced Label-Free Detection of DNA Using a Schottky-Contacted ZnO Nanowire Biosensor.

A sensitive and in situ selective label-free DNA sensor based on a Schottky-contacted ZnO nanowire (NW) device has been developed and utilized to detect the human immunodeficiency virus 1 gene in this work. Piezotronic effect on the performance of the DNA sensor is studied by measuring its output current under different compressive strains and target complementary DNA concentrations. By applying a -0.59% compressive strain to a ZnO NW-based DNA sensor, the relative current response is greatly enhanced by 454%. A theoretical model is proposed to explain the observed behaviors of the DNA sensor. This study provides a piezotronically modified method to effectively improve the overall performance of the Schottky-contacted ZnO NW-based DNA sensor.