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Aims: To investigate the association of methylation risk score (MRS) and its interactions with environmental factors with type 2 diabetes mellitus (T2DM) risk. Methods: We conducted a nested case–control study with 241 onset cases and 241 matched controls. Conditional logistic regression models were employed to identify risk CpG sites. Simple and weighted MRSs were constructed based on the methylation levels of ATP‐binding cassette G1 gene, fat mass and obesity associated gene, potassium voltage‐gated channel member 1 gene, and thioredoxin‐interacting protein gene previously associated with T2DM to estimate the association of MRS with T2DM risk. Stratified analyses were used to investigate interactions between MRS and environmental factors. Results: A total of 10 CpG loci were identified from the aforementioned genes to calculate MRS. After controlling for potential confounding factors, taking tertile 1 as reference, the odds ratios (ORs) and 95% confidence intervals (CIs) for T2DM of tertile 3 was 2.39 (1.36–4.20) for simple MRS and 2.59 (1.45–4.63) for weighted MRS. With per SD score increment in MRS, the OR (95% CI) was 1.66 (1.29–2.14) and 1.60 (1.24–2.08) for simple and weighted MRSs, respectively. J‐curved associations were observed between both simple and weighted MRSs and T2DM risks. Additionally, multiplication interactions for smoking and hypertension with simple MRS on the risk of T2DM were found, similarly for smoking and obesity with weighted MRS on the risk of T2DM (all Pinteraction <.05). Conclusion: Elevated simple and weighted MRSs were associated with increased risk of T2DM. Environmental risk factors may influence the association between MRS and T2DM. [ABSTRACT FROM AUTHOR]

Spontaneous coal combustion is one of the most common disasters in coal mine production. In order to explore the mechanism of coal spontaneous combustion more deeply, coal samples from the Yangdong wellfield of Jizhong Energy were selected for oxidative heat energy analysis experiments. A temperature-programmed experiment was selected to study the changes in characteristic parameters during the low-temperature oxidation of coal under different air supply conditions. TG-DSC experiments were conducted to study the characteristic temperature changes and thermodynamic characteristics of coal combustion processes at different heating rates. The study results show that the coal is most easily oxidised in the low-temperature oxidation stage when the air supply is 120 ml/min. The oxygen consumption rate, CO generation rate, and maximum and minimum heat release intensity are all greater at this airflow than under other conditions. The process of spontaneous combustion of coal has six characteristic temperature points and is divided into five stages. The characteristic temperature of the coal sample increased with the increase of the heating rate, and the TG/DTG curve showed a hysteresis phenomenon. DSC temperature curve shifts toward the high temperature with the increase of the heating rate, and the exothermic region is expanded. Isokinetic analysis (F-W-O and V-W) and Coats-Redfern model for calculating thermodynamic parameters. The activation energy of the samples decreased with the increase of the heating rate in the range of 2∼20°C·min−1 and showed a decreasing trend with the increase of the conversion rate. [ABSTRACT FROM AUTHOR]

The technology of liquid carbon dioxide phase change fracturing (LCPCF) was used to enhance the permeability of coal seams. The combination of mechanical tests, scanning electron microscopy (SEM) and high-pressure mercury intrusion porosimetry was adopted to study the damage characteristics of coal micro-structures. LCPCF had mechanical damage effects on coal micro-structures to varying degrees, and the maximum reduction in compressive strength reached approximately 25%. SEM results confirmed that surface morphology of coal was remarkably altered after conducting LCPCF. The fractal dimension (D) of coal subjected to LCPCF ranged from 1.5186 to 1.8794, demonstrating the three-stage changing trends. HP-MIP results showed that LCPCF mainly affected pores of > 100 nm within coal, and pores < 100 nm were hardly influenced. When 1.26 L of liquid CO2 was used to conduct physical blasting, at distance of < 1.5 m, the influence of LCPCF was strengthened. Affected by the high-energy gas and shock wave generated by LCPCF, meso-pores within coal were damaged and shifted to the larger pores, resulting in the increase in the number of macro-pores and micro-fractures. When distance was > 1.5 m, the obvious reduction in macro-pore and micro-fracture volumes implied that the fracturing effect was attenuated with the increase in distance. Once distance was > 6.0 m, pore and fracture structures within coal tended to be stable. Thus, in this study, the influence scope of LCPCF was around 6.0 m for a single fracturing borehole. [ABSTRACT FROM AUTHOR]