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Rock burst has become one of the most serious world's problems in coal resources mining, and fracture and movement of thick and hard strata in high position is the main reason to induce strong mining earthquake and rock burst. Multicoal seam mining of 10302 working face in Baodian coal mine is selected as an engineering background, which has thick and hard strata in high position. Using SOS microseismic monitoring system to collect microseismic events and date during multicoal seam mining, characteristic and difference of microseismic in multicoal seam mining under thick and hard rock in high position is analyzed systematically. The main research work is as follows: reveal temporal and spatial distribution and evolution law of microseismic and analyze difference and correlation of microseismic in multicoal mining under thick and hard strata in high position, especially the relationship between mining earthquake with high energy and fracture and movement of thick and hard strata in high position. With the characteristics of microseismic, rock burst mechanism and difference induced by thick and hard strata in high position are discussed. The research and achievement could make guidance to multicoal seam mining safety under thick and hard strata in high position. [ABSTRACT FROM AUTHOR]

Background. Tai Chi is effective in preventing heart disease (CHD) risk, but the molecular mechanism remains unclear. Mitogen-activated protein kinase (MAPK) signaling plays a critical role in the pathogenesis of CHD and can be activated by miR-126. Tai Chi may exert its protective function through the miR-126-modulated MAPK pathway. Methods. The CHD patients after PCI were randomized into the CG group (CG) (n = 19, normal care) and Tai Chi group (TG) (Tai Chi intervention, n = 17). Epicardial adipose tissue volume (EATV) (one main adverse cardiovascular event of CHD), HR (heart rate), QoL (quality of life) scores, and balance performance were measured in the two groups. The body fat content, abdominal subcutaneous fat, and visceral fat were measured to reflect the improvement of adipose tissue dysfunction. The levels of miR-126 and MAPK-associated molecules were measured in peripheral blood leukocytes. Meanwhile, the effects of miR-126 silence and mimic on MAPK-associated molecules were also explored in cardiac cell H9C2. Results. After the 3-month intervention, Tai Chi reduced EATV and HR and increased QoL scores and balance performance, respectively (P < 0.05). The fat percentage, body fat mass, and BMI were also significantly reduced after Tai Chi intervention (P < 0.05). The levels of miR-126, MAPK, JNK, and ERK in the TG group were lower than those in the CG group (P < 0.05). The miR-126 levels had a strong relationship with the values of EATV, HR, and QoL scores (P < 0.05). miR-126 silence or mimic inactivated or activated MAPK-associated molecules in the cardiac cell lines. Conclusions. Tai Chi improved CHD risk by inactivating the MAPK/ERK pathway via serum miR-126. [ABSTRACT FROM AUTHOR]

Summary: Spirobichroman‐based polymers have garnered considerable attention as promising gas separation membrane materials. Herein, two spirobichroman‐based diamines were synthesised using a pyridine heterocyclic ring with methyl substituents at different positions. The diamines were reacted with 4,4′‐(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and bis‐(3‐phthalyl anhydride) ether (ODPA) to achieve four polyimides functionalised by pyridine. The polymers performances were characterised by experimentally and molecular dynamics simulations. They showed high molecular weights of Mn = 9.4 to 14.0 × 104, excellent thermal stability, good solubility in a series of common organic solvents, and easy processability to form membranes. The membrane showed high gas pair selectivities of αCO2/CH4>30 and αCO2/N2>24, which were attributed to turnstile‐like rotary motions of the methyl and basic group of pyridine. The gas permeability results suggested that the substituents position of the methyl has little effect on the rigid molecular chain, unlike the densely packed flexible molecules chains. [ABSTRACT FROM AUTHOR]

Pipeline leak detection has always been a relatively difficult technical problem; especially in urban pipeline leak detection, there are still many problems to be solved. A multipoint leak detection and location method for urban gas pipelines based on variational mode decomposition and relative entropy was proposed. Firstly, the experiment pipeline system was built, and the original signal was collected by acoustic emission technology; then, a variational model method was used to decompose the signal to obtain multiple intrinsic mode function (IMF) components with different characteristic scales. According to the characteristics of relative entropy, each component was analyzed, the appropriate IMF component was selected, and the selected component was reconstructed to obtain the observation signal. The multipoint leakage location model of the urban gas pipeline was established. The number of source signals was estimated by singular value decomposition, and the leakage signals were separated; finally, the accurate location of leakage point was achieved by cross-correlation positioning. The results showed that the average relative error of the pipeline leak location results is 2.97%, and the leak location accuracy is significantly improved, achieving the purpose of precise location. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy, whose immunological mechanisms are still partially uncovered. Regulatory B cells (Bregs) and CD4+ regulatory T cells (Tregs) are subgroups of immunoregulatory cells involved in modulating autoimmunity, inflammation, and transplantation reactions. Herein, by studying the number and function of Breg and Treg cell subsets in patients with AML, we explored their potential role in the pathogenesis of AML. Newly diagnosed AML patients, AML patients in complete remission, and healthy controls were enrolled. Flow cytometry was used to detect percentages of Bregs and Tregs. ELISA was conducted to detect IL-10 and TGF-β in plasma. The mRNA levels of IL-10 and Foxp3 were measured with RT-qPCR. The relationship of Bregs and Tregs with the clinicopathological parameters was analyzed. There was a significant reduction in the frequencies of Bregs and an increase of Tregs in newly diagnosed AML patients compared with healthy controls. Meanwhile, patients in complete remission exhibited levels of Bregs and Tregs comparable to healthy controls. Furthermore, compared with healthy controls and AML patients in complete remission, newly diagnosed AML patients had increased plasma IL-10 but reduced TGF-β. IL-10 and Foxp3 mRNA levels were upregulated in the newly diagnosed AML patients. However, there were no significant differences in IL-10 and Foxp3 mRNA levels between patients in complete remission and healthy controls. Bregs and Tregs have abnormal distribution in AML patients, suggesting that they might play an important role in regulating immune responses in AML. [ABSTRACT FROM AUTHOR]

Suxiao jiuxin pill is considered an effective ancillary drug in patients with coronary heart disease. Although numerous small, single-center clinical trials have been conducted, the benefits and harms of suxiao jiuxin pill remain controversial. We performed a meta-analysis to clarify the efficacy of suxiao jiuxin pill on patients with coronary heart disease. Randomized controlled trials were identified by using the Cochrane Library, PubMed, Web of Science, Embase, Wanfang, Weipu, and China Knowledge Resource Integrated databases (until June 2016). Pooled relative risks (RR), weighted mean differences (WMD), and 95% confidence intervals (95% CIs) were estimated using random-effects models. Forty-one trials involving 6276 patients were included in our analysis. Administration of suxiao jiuxin pill significantly improved electrocardiogram (ECG) results when compared with other therapies (RR 1.32, 95% CI 1.26 to 1.38, and P<0.001). Subgroup analyses revealed that suxiao jiuxin pills improve ECG results more than salvia tablets (RR 1.54, 95% CI 1.41 to 1.67, and P<0.001), isosorbide dinitrate (RR 1.14, 95% CI 1.21 to 1.44, and P=0.001), nitroglycerin (RR 1.35, 95% CI 1.16 to 1.56, and P<0.001), and other drugs (RR 1.32, 95% CI 1.21 to 1.44, and P<0.001). Available evidence additionally suggests that suxiao jiuxin pills could significantly reduce total cholesterol (WMD −0.62 mmol/L, 95% CI −1.06 to –0.18 mmol/L, and P=0.005) and low-density lipoprotein (LDL) levels (WMD −1.12 mmol/L, 95% CI −1.42 to −0.82 mmol/L, and P<0.001) and increase high-density lipoprotein (HDL) levels (WMD 0.32 mmol/L, 95% CI 0.07 to 0.58 mmol/L, and P=0.014). However, no significant differences were observed in total triglyceride levels, plasma viscosity, hematocrit, and fibrinogen. No incidences of adverse reactions were observed after administration of suxiao jiuxin pill. Improvements in ECG results and lipid profiles were also observed after suxiao jiuxin administration compared to other therapies. It also decreased low-cut and high-cut whole blood viscosity without significant adverse reactions. [ABSTRACT FROM AUTHOR]