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Byline: Rongyan. Zhang, Gang. Zhao, Zhangjun. Yan, Hongmei. Xuan, Yan. Chen OBJECTIVES: The objectives of this study were to explore the median effective dose (ED[sub]50) and the dose required for [...]

Tropical cyclones have brought huge economic losses to Fujian Province. In order to achieve dynamic monitoring and early warning of wind and rain disaster risks caused by tropical cyclones, the disaster-causing mechanism of tropical cyclones is analyzed. A refined risk assessment method is developed to meet the needs of real-time decision-making on disaster prevention, mitigation, and reducing the economic losses caused by tropical cyclones.Through multiple rounds of rationality tests, 7 rain-induced disaster factors and 4 wind-induced disaster factors are picked out based on the tropical cyclone wind and rain data of 66 national meteorological stations from 1981 to 2021. And then, the risk assessment model of tropical cyclone disaster factors is established using the range standardization and correlation coefficient objective weighting method, and the risk level is divided by the natural breakpoint method and the disaster impacts.The results show that the risk assessment index system of disaster factors is reasonable, and the spatial distribution of disaster risk is investigated. The high rain risk areas are located along the coast, and the rain risk of Nanping and Sanming areas is low; the high wind risk area is significantly narrower than the high rain risk area, and the risk level decreases fast inland. Among them, the coastal areas from Luoyuan Bay to Chongwu are protected by the terrain barrier of Taiwan, and the risk is one level lower than that of the north and south parts of the coast. In addition, after the tropical cyclone lands on the east coast of Guangdong and moves northward, it often stays in the low-pressure cloud over the west of Fujian, resulting in a high risk area in the northwest of Fujian. Based on the spatial distribution of a single tropical cyclone, the disaster situation and the encrypted wind and rain data of regional stations, using the function of GIS and combining several typical tropical cyclone cases, a reasonable threshold for hazard classification is designed. It is targeted, especially urban waterlogging and mountain torrent disasters, which are basically consistent with the disaster situation, and provide more valuable reference information for meteorological disaster decision-making services.

Natural graphite ores are usually upgraded by froth flotation. However, complex processes with multistage grinding and flotation are required to achieve decent liberation and separation of graphite and gangue minerals. This study reports a short and improved flotation process for fine flake graphite ore by employing a thickening stage. The results indicated that increasing the regrinding concentration via thickening can improve the grinding efficiency and, thus, shorten the separation process. With thickening, a high-grade intermediate concentrate of 96.01% was obtained after three steps of cleaner flotation, which is close to the final concentrate after five steps. Particle size distribution analysis and FIB-SEM-EDS studies suggested that the main contribution of thickening–regrinding was to achieve better abrasion rather than attrition of the graphite flakes, thus liberating the interlayer impurities without reducing the size of the graphite flakes. This study offers a more cost-effective pathway for the simplified flotation of natural graphite ores. [ABSTRACT FROM AUTHOR]

Introduction: Atrial natriuretic peptide plays a potential role in obesity with unclear molecular mechanisms. The objective of this study was to examine the association between its coding gene (natriuretic peptide A [NPPA]) methylation and obesity. Methods: Peripheral blood DNA methylation of NPPA promoter was quantified at baseline by targeted bisulfite sequencing for 2,497 community members (mean aged 53 years, 38% men) in the Gusu cohort. Obesity was repeatedly assessed by body mass index (BMI) and waist circumference (WC) at baseline and follow-up examinations. The cross-sectional, longitudinal, and prospective associations between NPPA promoter methylation and obesity were examined. Results: Of the 9 CpG loci assayed, DNA methylation levels at 6 CpGs were significantly lower in participants with central obesity than those without (all p < 0.05 for permutation test). These CpG methylation levels at baseline were also inversely associated with dynamic changes in BMI or WC during follow-up (all p < 0.05 for permutation test). After an average 4 years of follow-up, hypermethylation at the 6 CpGs (CpG2 located at Chr1:11908348, CpG3 located at Chr1:11908299, CpG4 located at Chr1:11908200, CpG5 located at Chr1:11908182, CpG6 located at Chr1:11908178, and CpG8 located at Chr1:11908165) was significantly associated with a lower risk of incident central obesity (all p < 0.05 for permutation test). Conclusions: Hypomethylation at NPPA promoter was associated with increased future risk of central obesity in Chinese adults. Aberrant DNA methylation of the NPPA gene may participate in the mechanisms of central obesity. [ABSTRACT FROM AUTHOR]

Abstract We study a discrete delay Mosquito population equation. Firstly, we study the stability of the equilibria of the system and the existence of period-two bifurcation by analyzing the characteristic equation. Secondly, the direction and stability of the bifurcation are determined by using the normal form theory. Finally, some computer simulations are performed to illustrate the analytical results found.