Immobilization of the bacteria A. simplex by-2-13 was obtained by irradiation polymerization with an electron beam and gamma-radiation at 0°C. Prednisone acetate (P. A.) was derived from cortisone acetate (C. A.) by 1,2-dehydrogenation, catalyzed by immobilized A. simplex by-2-13. The immobilized bacteria were used 10 times in succession with a transformation percentage ranging from 77 to 86% for electron beam radiation and 79 to 99% for gamma radiation. Dehydrogenation, was carried out at pH 7.2, 34°C, 180–200 r.p.m. for 24 hours. 3% (v/v) anhydrous alcohol was added to the system at onset. Scanning electron micrographs documented the structure of the immobilized bacteria. In this work, the effect of absorbable doses of radiation and the reaction time of non-immobilized bacteria on dehydrogenase activity were studied. The effect of pH, temperature and concentration of substrate were also studied.
Authors:Jun Tang, Gengmei Xing, Hui Yuan, Xingfa Gao, Long Jing, Shukuan Wang, Yue Cheng, and Yuliang Zhao
The electronic properties of the metal atoms encaged in a fullerence cage were investigated using synchrotron X-ray photoelectron
spectroscopy. Systematic variations in photoemission of valence band of Gd@C82, Gd@C82(OH)12, and Gd@C82(OH)22 were observed in Gd 5p levels. The results suggest that the electronic properties of the inner metal atom can be efficiently
modulated by surface chemistry of the fullerene cage.
Authors:Yue Cheng, Kaiming Liu, Gengmei Xing, Hui Yuan, Long Jing, and Yuliang Zhao
The water-solubilization of metallofullerenes is important for their potential applications, but their formation processes
are still not clear, and the formation yield is uncontrollable. In this paper, we quantitatively studied the water-solubilizing
process of Gd@C82 with hydroxylation reaction using ICP-MASS techniques. For the first time, it was found that the formation yield of the multihydroxylated
Gd@C82 is declined quickly with the break up of carbon cage of Gd@C82 in the hydroxylated processes. The observation revealed a way to control the hydroxylation processes and increase the formation
Nanosized copper particles are widely used in fields of lubricants, polymers/plastic, metallic coating and ink. Recently,
we found that copper particles in different sizes can lead to different toxicological effects. To clarify the target organs
of copper particles of different sizes, the inductively coupled plasma mass spectroscopy (ICP-MS) was employed to evaluate
the distribution of copper in different organs of mice after a single dose oral exposure. The results suggest that the main
target organs for copper nanoparticles are kidney, liver and blood. Liver is the main damaged organ.
Recently, it was reported that the toxicity of copper particles increases with the decrease of the particle size on a mass
basis. To understand this phenomenon, inductively coupled plasma mass spectrometry (ICP-MS) techniques and in vitro chemical
studies were carried out to explore how they produce toxicity in vivo. The results suggest that when the sizes of particles
become small and down to a nanoscale, copper becomes extremely reactive in a simulative intracorporeal environment. The nanosized
copper particles consume the hydrogen ions in stomach more quickly than micron ones. These processes further convert the copper
nanoparticles into cupric ions whose toxicity is very high in vivo.
The aim of this study was to investigate the mechanisms of Internet gaming disorder (IGD) and the associated interaction effects of childhood trauma, depression and anxiety in college students.
Participants were enrolled full-time as freshmen at a University in the Hunan province, China. All participants reported their socio-demographic characteristics and undertook a standardized assessment on childhood trauma, anxiety, depression and IGD. The effect of childhood trauma on university students' internet gaming behaviour mediated by anxiety and depression was analysed using structural equation modelling (SEM) using R 3.6.1.
In total, 922 freshmen participated in the study, with an approximately even male-to-female ratio. A mediation model with anxiety and depression as the mediators between childhood trauma and internet gaming behaviour allowing anxiety and depression to be correlated was tested using SEM. The SEM analysis revealed that a standardised total effect of childhood trauma on Internet gaming was 0.18, (Z = 5.60, 95% CI [0.02, 0.05], P < 0.001), with the direct effects of childhood trauma on Internet gaming being 0.11 (Z = 3.41, 95% CI [0.01, 0.03], P = 0.001), and the indirect effects being 0.02 (Z = 2.32, 95% CI [0.00, 0.01], P = 0.020) in the pathway of childhood trauma-depression-internet gaming; and 0.05 (Z = 3.67, 95% CI [0.00, 0.02], P < 0.001) in the pathway of childhood trauma-anxiety-Internet gaming. In addition, the two mediators anxiety and depression were significantly correlated (r = 0.50, Z = 13.54, 95% CI [3.50, 5.05], P < 0.001).
The study revealed that childhood trauma had a significant impact on adolescents' Internet gaming behaviours among college students. Anxiety and depression both significantly mediated the relationship between childhood trauma and internet gaming and augmented its negative influence. Discussion of the need to understand the subtypes of childhood traumatic experience in relationship to addictive behaviours is included.