Test study on rupture process and permeability properties of coal-rock in simulating mining stress effect

A test system was designed by using a set of self-made experimental devicesof coupled coal-gas in simulating mining stress effect, combining the equipment withRMT-150B rock mechanical experimental system, monitoring the rupture process ofcoal-rock with an acoustic emission (AE) device and collecting gas-flow rate andgas-stress data in real-time automatically with a gas flow-meter and gas pressure sensor.The fracture process and permeability properties test of the coal-rock in mining stress effect was carried out. Test results indicate that AE events and variation of stresses have thesame variance tendency and the rupture process of coal-rock can be monitored by AE.The relation curves among stresses, parameters of AE and permeability properties demonstrate that the permeability of coal-rock decreases gradually at quasi-elastic stage, increases gradually at plastic damage micro-fracture stage, rises suddenly near the peakpoint and has multi-variation at post-peak slip stage. From the results, such conclusioncan be drawn that the variation of permeability can be monitored by AE parameters orstress change.

胃癌患者血清PG、G-17、IL-6、IL-23、IL-17、TNF-α的检测价值

目的分析胃癌患者血清胃蛋白酶原(PG,PGⅠ、PGⅡ)、胃泌素-17(G-17)、白介素(IL)-6、IL-23、IL-17、肿瘤坏死因子-α(TNF-α)的变化及联合检测价值。方法选择2022年1月-2023年2月于我院就诊的胃癌患者122例为观察组,100例体检健康受试者为对照组,进行平行对照研究。PGⅠ、PGⅡ、G-17采用双抗体夹心免疫检测法,IL-6、IL-23、IL-17、TNF-α采用酶联免疫吸附试验(ELISA)检测。比较两组血清PGⅠ、PGⅡ、G-17、IL-6、IL-23、IL-17、TNF-α水平,观察组TNM肿瘤分期Ⅰ~Ⅱ期与Ⅲ~Ⅳ期各血清指标的差异。采用受试者工作特征曲线(ROC曲线)分析各血清指标联合检测对胃癌进展(Ⅲ~Ⅳ期)的预测价值。结果观察组血清PGⅠ低于对照组,血清PGⅡ、G-17、IL-6、IL-23、IL-17、TNF-α水平均高于对照组(P<0.05);胃癌患者TNMⅠ~Ⅱ期血清PGⅠ高于TNMⅢ~Ⅳ期,血清PGⅡ、G-17、IL-6、IL-23、IL-17、TNF-α水平均低于TNMⅢ~Ⅳ期(P<0.05)。单项血清检查中PGⅠ预测胃癌进展AUC较高,为0.976,但各血清指标联合检测预测胃癌进展(Ⅲ~Ⅳ期)的AUC更高,为0.984,特异度98.90%,灵敏度92.60%。结论胃癌患者PGⅡ、G-17、IL-6、IL-23、IL-17、TNF-α水平呈现高表达,PGⅠ水平呈低表达,不同TNM分期差异显著,可预测胃癌进展,以联合检测效用最高。