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Corn starch/polyvinyl alcohol (PVA) composite films containing different concentrations of tea polyphenols (TP) were fabricated by casting. Scanning electron microscopy and atomic force microscopy images showed that when the TP content was less than 8%, the films were relatively uniform, but with increasing TP concentration, the films became rougher and uneven. Fourier transform infrared, 13C nuclear magnetic resonance, and X‐ray diffraction techniques were used to investigate the interactions between TP, starch, and PVA. The incorporation of TP deepened the color and increased the opacity and solubility of the films. The tensile strength and elongation at break first increased and then decreased with increasing TP content. Furthermore, the addition of TP increased the antioxidant activity of the films, specifically, their ability to scavenge 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azinobis (3‐ethylberizothiazoline‐6‐sulfonic acid). The addition of TP can effectively enhance the performance of starch composite films and their potential for application in antioxidant food packaging. [ABSTRACT FROM AUTHOR]

Tea is one of the most popular beverage in the world and may be contaminated by fungi and mycotoxins during processing. To analyse aflatoxin B1 (AFB1) and sterigmatocystin (STC) in three types of tea, a simple, fast, sensitive and reliable method of these two myxotoxins was developed. Recoveries obtained ranged from 95.9% to 118.0% and the RSDs were between 0.3% and 11.2%. The range of LODs was 0.2–0.45 µg/kg for AFB1 and 0.04–0.12 µg/kg for STC. The range of LOQs was 0.67–1.73 µg/kg for AFB1 and 0.13–0.40 µg/kg for STC. The optimised procedure was applied to analyse 126 tea samples randomly collected from different markets in China. AFB1 was not detected, but STC was determined in 17 samples with concentrations ranging from 0.13 to 4.48 µg/kg. The detection rate of STC was 5%, 8.9% and 33.3% in black tea, green tea and Oolong tea, respectively. [ABSTRACT FROM AUTHOR]

Data regarding ochratoxin A (OTA) and zearalenone (ZEA) contamination in feed in South China are limited. Here, we evaluated OTA and ZEA contamination in 514 poultry feed samples collected from South China. We validated a modified QuEChERS (quick, easy, cheap, effective, rugged, and safe) method and the mycotoxins were quantified by high‐pressure liquid chromatography–tandem mass spectrometry. OTA and ZEA were detected in 2.92% and 100% of the feed samples, respectively. Furthermore, 0%, 0.68%, and 7.0% of Hainan, Guangdong, and Guangxi feed samples were contaminated with OTA, at mean concentrations of 0.00, 1.14, and 0.88 μg/kg, respectively. All samples were contaminated with ZEA, and the mean concentrations were 2094.1, 14.3, and 8.73 μg/kg in the samples from Hainan, Guangdong, and Guangxi, respectively. The findings of this study indicate the strong need for intense monitoring of mycotoxin, especially ZEA, contamination in feed. [ABSTRACT FROM AUTHOR]

AiWalker is a newly developed robot-assisted gait training system, which features over-ground walking paradigm and somatosensory stimulation during training compared to commonly-used robot-assisted gait training devices (e.g. Lokomat). However, no study has examined its true therapeutic effect and possible mechanism or mediating factor(s). To investigate 1) the therapeutic effect of AiWalker on the balance and walking ability in patients with stroke, and 2) whether the improvement in somatosensory function represents one of the possible mediating factors for such effect. Three patients with impaired balance and walking ability due to stroke were recruited. Two patients received AiWalker training plus conventional training; while the other one only experienced conventional training. Standing balance and walking ability were assessed before and after all the training, which were represented by 6 variables. Lower limb somatosensory function was examined using Fugl-Meyer Assessment Scale. Five out of the 6 variables showed greater changes in patients who received AiWalker training compared to the one who only experienced conventional training. Greater improvement in lower limb somatosensory function was observed in one patient who received AiWalker training compared to the one who only experienced conventional training. The novel robot-assisted gait training system may elicit greater improvement of balance and walking ability in patients with stroke compared to conventional interventions. Lower limb somatosensory function may be improved by AiWalker, and its improvement might represent one of the possible mediating factors for the therapeutic effect of AiWalker on balance and walking ability. [ABSTRACT FROM AUTHOR]

The controllable assembly of three-dimensional (3D) nanomaterials from a one-dimensional (1D) precursor has always been one of the difficulties in nanomaterial synthesis. Here, we use a gentle hydrolysis of 1D metal–organic frameworks (MOFs) to prepare 3D CoCO3, with full and convenient recovery of costly organic ligands. For the first time, 1D nanowires of Co-MOF-74 were transformed into CoCO3 with different 3D morphologies by introducing different modulators of urea or hexamethylenediamine (HMT). The formation mechanism (using urea as a modulator) has been elucidated and has revealed a conversion process from 1D nanowires of Co-MOF-74, subsequently to 1D rod-like stacked 3D Co-MOF-74 nanospheres through aggregate assembly, and then to 3D hydrangea like CoCO3-H. After calcination, it was found that the obtained 3D Co3O4 catalyst derived from 3D CoCO3 exhibited significantly enhanced catalytic performance for VOC degradation compared to 1D Co3O4 directly calcined from Co-MOF-74. In addition, the morphology and the catalytic performance of the catalysts prepared with the recycled ligands were consistent with those of catalysts made from fresh ligands. [ABSTRACT FROM AUTHOR]

Manganese oxides with different crystal phases (i. e. α‐MnO2, γ‐MnO2 and β‐MnO2) were synthesized for catalytic oxidation of toluene. The catalytic activity was strongly influenced by the crystal phases of MnO2. α‐MnO2 exhibited the highest catalytic activity with a 50 % toluene conversion (T50) at 229 °C and a 90 % toluene conversion (T90) at 238 °C, followed by γ‐MnO2 (T90=252 °C) and β‐MnO2 (T90=278 °C). The remarkable catalytic activity of α‐MnO2 was attributed to its superior redox property and lattice oxygen mobility. Different intermediates were detected on the surfaces of α‐, γ‐ and β‐MnO2 by in situ diffuse reflectance infrared Fourier transform spectroscopy (in‐situ DRIFTS). Benzoate species were found to be the key intermediates on α‐MnO2 at 240 °C, while benzoyl oxide species and benzoate were the major intermediates on γ‐MnO2 at 260 °C. The surface of β‐MnO2 was mainly covered by carbonate and benzoate species after the adsorption of toluene at 280 °C. [ABSTRACT FROM AUTHOR]