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The paper proposes a diagnosis technique for transformer faults and a technological process for hidden peril management based on vibration analysis by analyzing pluses and minuses of conventional fault test methods for transformers. Through vibration spectrum， the cause of a slight increase in acetylene content of a UHV reactor is analyzed and the fault source is fitted， analyzed and located based on the amplitude trend distribution； through on-site modal testing， the inherent frequencies of structural components are obtained to diagnose and precisely control structural resonance faults of the main transformer cooler of a converter station； through vibration monitoring， the impact on the surrounding transformers when the ±800 kV Fulong-Fengxian DC system is put into operation and in the case of single and double pole operation is analyzed to provide data support for the safe and stable operation of equipment. The transformer fault diagnosis and hidden peril management of transformer based on vibration analysis enable fault diagnosis in the early stage and rids equipment of damages from grid disturbance.

The bioactivity of tea polysaccharides (TPs) has been widely reported, but studies to date have focused on green tea. Some human health investigations have implied that black tea may possess potential antidiabetic effects, but less is known about their potential role and related antidiabetic mechanism. The present study was, therefore, conducted to investigate the chemical properties and antidiabetic activity of TPs from black tea. Monosaccharide composition revealed that Alduronic acid (77.8 mol%) considerably predominated in the fraction. TP conformation analysis indicated that three components in TPs were all typical of high-branching structures. Oral administration of TPs could effectively alleviate fasting blood glucose in type 2 diabetes mellitus (T2D) mice, with the values 23.6 ± 1.42, 19.6 ± 2.25, and 16.4 ± 2.07 mmol/L in the 200, 400, and 800 mg/kg·BW groups, respectively. Among these TPs groups, the 800 mg/kg·BW groups significantly decreased by 37.88% when compared with the T2D+water group (p < 0.05). Further studies demonstrated that TP treatment upregulated the expression of p-Akt/p-PI3K (p < 0.001). Additionally, TP treatment significantly promoted glucose transporter protein 2 (GLUT2) translocation in the liver (p < 0.001). These findings suggest that TPs from black tea protect against T2D by activating PI3K/Akt/GLUT2 signaling and might serve as a novel therapeutic candidate for T2D. [ABSTRACT FROM AUTHOR]

High levels of fine particulate matter (PM2.5) is linked to poor air quality and premature deaths, so haze pollution deserves the attention of the world. As abundant inorganic components in PM2.5, ammonium nitrate (NH4NO3) formation includes two processes, the diffusion process (molecule of ammonia and nitric acid move from gas phase to liquid phase) and the ionization process (subsequent dissociation to form ions). In this study, we discuss the impact of meteorological factors, emission sources, and gaseous precursors on NH4NO3 formation based on thermodynamic theory, and identify the dominant factors during clean periods and haze periods. Results show that aerosol liquid water content has a more significant effect on ammonium nitrate formation regardless of the severity of pollution. The dust source is dominant emission source in clean periods; while a combination of coal combustion and vehicle exhaust sources is more important in haze periods. And the control of ammonia emission is more effective in reducing the formation of ammonium nitrate. The findings of this work inform the design of effective strategies to control particulate matter pollution. [ABSTRACT FROM AUTHOR]

SUMMARY: Dendrobium officinale is edible and has medicinal and ornamental functions. Polysaccharides and flavonoids, including anthocyanins, are important components of D. officinale that largely determine the nutritional quality and consumer appeal. There is a need to study the molecular mechanisms regulating anthocyanin and polysaccharide biosynthesis to enhance D. officinale quality and its market value. Here, we report that high light (HL) induced the accumulation of polysaccharides, particularly mannose, as well as anthocyanin accumulation, resulting in red stems. Metabolome and transcriptome analyses revealed that most of the flavonoids showed large changes in abundance, and flavonoid and polysaccharide biosynthesis was significantly activated under HL treatment. Interestingly, DoHY5 expression was also highly induced. Biochemical analyses demonstrated that DoHY5 directly binds to the promoters of DoF3H1 (involved in anthocyanin biosynthesis), DoGMPP2, and DoPMT28 (involved in polysaccharide biosynthesis) to activate their expression, thereby promoting anthocyanin and polysaccharide accumulation in D. officinale stems. DoHY5 silencing decreased flavonoid‐ and polysaccharide‐related gene expression and reduced anthocyanin and polysaccharide accumulation, whereas DoHY5 overexpression had the opposite effects. Notably, naturally occurring red‐stemmed D. officinale plants similarly have high levels of anthocyanin and polysaccharide accumulation and biosynthesis gene expression. Our results reveal a previously undiscovered role of DoHY5 in co‐regulating anthocyanin and polysaccharide biosynthesis under HL conditions, improving our understanding of the mechanisms regulating stem color and determining nutritional quality in D. officinale. Collectively, our results propose a robust and simple strategy for significantly increasing anthocyanin and polysaccharide levels and subsequently improving the nutritional quality of D. officinale. Significance Statement: Dendrobium officinale is edible and has medicinal and ornamental functions. Polysaccharides and flavonoids are the predominant bioactive compounds produced by D. officinale. However, the relationship between anthocyanin biosynthesis and polysaccharide biosynthesis is unclear. Our study revealed a mechanism underlying the high‐light‐induced co‐regulation of anthocyanin biosynthesis and polysaccharide biosynthesis in D. officinale, improving our understanding of how plants coordinate anthocyanin and polysaccharide biosynthesis. [ABSTRACT FROM AUTHOR]