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  • Author or Editor: Yan Wang x
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Abstract

A novel method was established for analysing trace four acidic phytohormones, namely, indole-3-acetic acid, 3-indolebutyric acid, abscisic acid, and 1-naphthylacetic acid, using magnetic ordered mesoporous carbon (MOMC). MOMC was facilely synthesised via self-assembly strategy with a direct carbonisation process. The properties of MOMC were characterised using various instruments. MOMC exhibited excellent adsorption capacity towards the analytes. Various critical parameters which may influence the enrichment efficiency were evaluated, including amount of MOMC, extraction conditions, and desorption conditions. An efficient method based on MOMC magnetic solid-phase extraction coupled with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed to analyse the trace four acidic phytohormones, with good correlation coefficients (R 2 = 0.9965–0.9998) and low limits of detection (0.13–9.7 ng L−1, S/N = 3). Trace acidic phytohormones in Agaricus bisporus and Hypsizygus marmoreus samples were determined with satisfactory recoveries (91.8–108%) and reproducibility (2.6–6.3%). The features indicated that MOMC provides an efficient platform for mushroom sampling; the developed method is convenient, promising, and sensitive for the detection of trace phytohormones in complicated mushroom samples.

Open access

Abstract

Background and aims

Mobile phone addiction (MPA) is emerging among adolescents, especially during the COVID-19 pandemic. Nevertheless, there is a dearth of knowledge regarding the correlation between MPA and suicide behaviors and its mechanism. The objective of the current study is exploring the direct effect of MPA on suicide behaviors and the indirect effect through poor sleep quality.

Methods

A total of 18,900 Chinese adolescents aged 12 to 18 were recruited via a multi-stage cluster sampling method.

Results

The prevalence of MPA and poor sleep quality was 26.2 and 23.1%, respectively. During the past year, 24.4% participants were involved in suicide behaviors. Specifically, suicide ideators, suicide planners, and suicide attempters were 10.7, 8.4, and 5.3%, respectively. Particularly, rural females had the highest prevalence of suicide behaviors, MPA, and poor sleep quality. Logistic regression analysis showed that MPA was significantly associated with suicide ideators (OR = 1.22, 95% CI: 1.09–1.37, p < 0.001) and planners (OR = 1.18, 95% CI: 1.04–1.34, p < 0.05), but not for suicide attempters (p > 0.05). Structural equation modelling demonstrated that MPA had direct effect on suicide behaviors (β = 0.145, 95% CI = 0.127–0.160), and poor sleep quality partially mediated the relationship (the mediating ratio was 46.7%). The mediating ratio of poor sleep quality was the highest in urban males.

Conclusions

MPA has both direct and indirect effects on suicide behaviors. For suicide prevention, limited mobile phone use and improvement sleep quality may be practical for adolescents. Additionally, more efforts of intervention could give priority to rural girls.

Open access

Abstract  

In boron neutron capture therapy (BNCT), the proportion of the fast neutron in the tumor (PFN) must be no more than 3%. If a D–T neutron generator is used as a thermal neutron source in BNCT, the moderator must be optimized to decrease the PFN. Based on the analysis of the theory, water, heavy water, polythene, graphite, lead, and tungsten were used to moderate the fast neutrons. If the three-layer material is composed of a 4 cm thickness layer of tungsten, a 13 cm thickness layer of lead, and a 23 cm thickness layer of heavy water, its thermalization efficiency (TE) is highest, which is increased by 191.5% than the maximum TE moderated by single-layer materials and by 19.3% than the maximum TE moderated by double-layer materials.

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Abstract

In this study, the activities of four ginsenosides Rc, Re, Rd, and Rf on splenic lymphocytes growth were studied by microcalorimetry. Some qualitative and quantitative information, such as the metabolic power–time curves, growth rate constant k, maximum heat-output power of the exponential phase P max and the corresponding appearance peak time t max, total heat output Q t, and promotion rate R p of splenic lymphocytes growth affected by the four ginsenosides were calculated. In accordance with thermo-kinetic model, the corresponding quantitative relationships of k, P max, t max, Q t, R p, and c were established. Also, the median effective concentration (EC50) was obtained by quantitative analysis. Based on both the quantitative quantity–activity relationships (QQAR) and EC50, the sequence of promotion activity was Rc > Re > Rd > Rf. The analysis of structure–activity relationships showed that the number, type, and position of sugar moieties on the gonane steroid nucleus had important influences on the promotion activity of Rc, Re, Rd, and Rf on splenic lymphocytes growth. Microcalorimetry can be used as a useful tool for determining the activity and studying the quantity–activity relationship of drugs on cell.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Zhang Yuanxun
,
Lin Erhkang
,
Li Deyi
,
Wang Yinsong
,
Yu Yuehchung
,
Wang Changwan
,
Shen Waiguo
,
Zhi Min
,
Zhang Guilin
, and
Li Yan

Abstract  

In order to evaluate the evolution of contamination we collected river water and sediment samples in the every spring season since 1998. The elemental analysis of water and sediment samples was performed by PIXE using the 3×2 MeV NEC Tandem accelerator at the Taipei Institute of Physics. The characterization of - and -radioactive levels for water and sediment samples was performed by a BH1216, low background radioactivity instrument at the Shanghai Institute of Nuclear Research. The PIXE results showed that the elemental contents of Cl, K, Ca, Cr, Mn, Fe, Zn and Pb in river water gradually decreased with the rising tide. At high tide, their concentrations were minimum and then increased toward the ebb tide. The analysis also demonstrated that the radioactivity of water samples had been gradually decreasing year by year. It was found that the decreasing rate of -radioactivity was a little quicker than that of -radioactivity. Further aspects of environmental data evaluation and assessment are also discussed.

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A comparative proteomic analysis of grain proteins during five grain developmental stages of wheat cultivar Chinese Spring (CS) and its 1Sl/1B substitution line CS-1Sl(1B) was carried out in the current study. A total of 78 differentially expressed protein (DEP) spots with at least 2-fold expression difference were detected by two-dimensional electrophoresis (2-DE). Among these, 73 protein spots representing 55 differentially expressed proteins (DEPs) were successfully identified by matrix-assisted laser desorption/ionization time-offlight tandem mass spectrometry (MALDI-TOF/TOF-MS). Differential protein spots between the two genotypes were analyzed by cluster software, which revealed significant proteome differences. There were 39 common spots (including 33 DEPs) that showed significant difference between the two lines across five grain developmental stages, of which 14 DEP spots (including 11 DEPs) were mainly involved in carbohydrate metabolism that were encoded by the genes on 1B chromosome while 25 DEP spots (including 12 DEPs) were mainly related to stress response and gluten quality that were encoded by 1S1 chromosome. These results indicated that the Sl genome harbors more stress and quality related genes that are potential valuable for improving wheat stress resistance and product quality.

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Abstract  

The kinetic characteristic of thermal decomposition of the Emulsion Explosive Base Containing Fe and Mn elements (EEBCFM) which was used to prepare nano-MnFe2O4 particles via detonation method was investigated by means of non-isothermal DSC and TG methods at various heating rates of 2.5, 5 and 7.5°C min−1respectively under the atmosphere of dynamic air from room temperature to 400°C. The results indicated that the EEBCFM was sensitive to temperature, especially to heating rate and could decompose at the temperature up to 60°C. The maximum speed of decomposition (dα/dT)m at the heating rate of 5 and 7.5°C min−1 was more than 10 times of that at 2.5°C min−1 and nearly 10 times of that of the second-category coal mine permitted commercial emulsion explosive (SCPCEE). The plenty of metal ions could seriously reduce the thermal stability of emulsion explosive, and the decomposition reaction in the conversion degree range of 0.0∼0.6 was most probably controlled by nucleation and growth mechanism and the mechanism function could be described with Avrami-Erofeev equation with n=2. When the fractional extent of reaction α>0.6, the combustion of oil phase primarily controlled the decomposition reaction.

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Journal of Thermal Analysis and Calorimetry
Authors:
Zhongliang Zhang
,
Xuezhong Sun
,
Weixia Zhou
,
Liqiang Zhang
,
Bin Li
,
Minggui Wang
,
Baozhen Yan
, and
Fu Tan

Abstract  

Calorimetric studies were undertaken of the heat, observed during the electrolysis of H2O in normal open and closed cell as well, employing palladium cathode. A difference in heat observed during the process between opened and closed system was found. Heat generated under different conditions was presented as a function of the working current density or voltage. Such results were briefly discussed according to general thermodynamics and electrochemistry.

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Abstract

The power–time curves of mice splenic lymphocytes growth at 37 °C affected by ginsenoside Rh2 were determined by microcalorimetry using a 3114/3236 TAM air bioactivity monitor with ampoule mode. Then, the minimal inhibitory concentration (MIC) of Rh2 on splenic lymphocytes growth was determined by serial dilution method. From factor analysis (FA) on six quantitative thermokinetic parameters from the power–time curves, the activity of Rh2 on splenic lymphocytes could be quickly evaluated by analyzing the changes in the two main parameters: growth rate constant k, and maximum heat-output power, P m. The results showed that Rh2 had strong inhibitory activity on splenic lymphocytes growth, and this inhibitory activity was strengthened with increasing concentration of Rh2 in the concentration range of 1.0–32.0 μg mL−1. This strong inhibitory also could be confirmed from the MIC of 50.0 μg mL−1 of Rh2 on splenic lymphocytes growth in RPMI-1640 culture medium. This study illustrated that microcalorimetry could not only offer a useful method for evaluating the activity of drugs, but also serve as a quantitative, sensitive, and simple analytic tool for the evaluation of drugs on cell growth.

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Abstract  

The catalytic synthesis of 2-amino-1-butanol from 1,2-butanediol and ammonia was studied in a continuous fixed-bed reactor. The catalysts prepared by doping Co–Ba/γ-Al2O3 with Sr, Ni, Ca, Zn, La, Fe, Mg, Zr, Mn, Cr were examined, among which the Co–Ba–Fe/γ-Al2O3 catalyst showed the best catalytic performance. These catalysts were characterized by XRD, XPS, and TPR. It was found that the addition of iron led to the formation of crystalline Co7Fe3, which modified the catalytic activity of Co species, inhibited the generation of CoAl2O4, improved the stability and enhanced the reduction of the Co–Ba–Fe/γ-Al2O3 catalyst. The conversion of 1,2-butanediol was 72.9% and the selectivity of 2-amino-1-butanol achieved 73.3% under the optimum reaction conditions.

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