Search

The development of hydrogels combining superior mechanical property attracts researchers' attention in recent years. Here, a novel nanocomposite hydrogel is prepared by one‐step photo‐polymerization of acrylic acid (AA) and N,N‐dimethylacrylamide (DMAA) in the presence of hydroxyapatite nanoparticles (HAp NPs) and aluminum hydroxide nanoparticles (Al(OH)3 NPs). The resulting transparent hydrogel exhibits ultrahigh toughness of 28.3 MJ m−3, high strength of 2.8 MPa, large elongation of 1300%, excellent self‐recovery and good biocompatibility. The crosslinking mechanism is contributed to the ionic coordination interaction between cations absorbing on the surface of nanoparticles and carboxyl groups of the polymer chain, and the synergistic toughening effect between HAp NPs and Al(OH)3 NPs is responsible for improving the strength and toughness simultaneously. Furthermore, this synergistic toughening strategy may provide a universal method for designing and constructing high strength nanocomposite hydrogels in many applications, especially for artificial cartilages. POLYM. COMPOS., 40:942–951, 2019. © 2018 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

This study was designed to assess the effects of exposure to arsenic in drinking water on visual and vibrotactile function in residents of the Bamen region of Inner Mongolia, China. Arsenic was measured by hydride generation atomic fluorescence. 321 participants were divided into three exposure groups- low (non-detectable-20), medium (100-300) and high (400-700 microg/l) arsenic in drinking water (AsW). Three visual tests were administered: acuity, contrast sensitivity and color discrimination (Lanthony's Desaturated 15 Hue Test). Vibration thresholds were measured with a vibrothesiometer. Vibration thresholds were significantly elevated in the high exposure group compared to other groups. Further analysis using a spline regression model suggested that the threshold for vibratory effects is between 150-170 microg/l AsW. These findings provide the first evidence that chronic exposure to arsenic in drinking water impairs vibrotactile thresholds. The results also indicate that arsenic affects neurological function well below the 1000 microg/I concentration reported by NRC (1999). No evidence of arsenic-related effects on visual function was found.