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Earthquake-triggered mudflows are typical in scale and hazard, and their formation mechanism is extremely complex. In this study, the liquefaction and mobility mechanisms of a catastrophic mudflow, namely, the Yongguangcun (YGC) mudflow, in Minxian, Gansu Province, China, under the coupled action of historical earthquakes, active faults, groundwater, long-term rainfall before an earthquake, and the 2013 Mw6.6 Minxian–Zhangxian earthquake were systematically analyzed. Through a detailed field investigation and laboratory testing, the stratigraphic structure of the YGC mudflow was revealed, a geomechanical model was established, and the complex chain process leading to the formation of the YGC mudflow was elucidated. This process includes sliding along the contact zone between the loess and strongly weathered mudstone, liquefaction of the saturated loess under the groundwater table, and liquefaction and collapse of the unsaturated loess above the groundwater table. The slightly low terrain provides the topographic conditions required for groundwater convergence, and sets the conditions for the deformation and further liquefaction of saturated loess during earthquakes. The undulating terrain in the meizoseismal area enhances the complexity of the earthquake waves. In summary, the YGC mudflow was caused by long-term geological evolution and the synergistic effects of other factors; and the site conditions, such as the local topography and groundwater, are the fundamental reasons for the failure and mobility differences between the YGC mudflow and the eastern landslide. The results of the investigation of this mudflow would enrich our understanding of mudflows, promote research on the formation mechanism of geological disasters under complex conditions on the Loess Plateau, and provide important information for improving the scientific prevention and control of landslides of the same type. [ABSTRACT FROM AUTHOR]

Background: The traditional herbal medicinal formula Da-Cheng-Qi decoction (DCQD) has long been used to treat pancreatitis in China; however, the underlying mechanisms remain unclear. Aim: To investigate whether DCQD is beneficial to the patients with lung injury in severe acute pancreatitis (SAP); if it is, then to explore the lung protective effect of DCQD and the mechanism involved in rats. Methods: DCQD was enema administered to 70 patients for 7 days. Mortality, (multi)organ failure during admission were observed, blood samples for laboratory analysis were drawn on admission, on Days 3, 7, and 14 of the treatment. We also experimentally examined the function of two doses of DCQD in SAP rat models. IL-1β, IL-6, and IL-10 mRNA expression in rat lungs was measured quantitatively by the RT-PCR method and confirmed by morphometric studies of the lungs. Results: It was demonstrated that the administration of DCQD did shorten the average time that patients suffered acute respiratory distress syndrome (ARDS). Compared with untreated rats, the lungs of rats treated with DCQD showed significantly lower levels of proinflammatory cytokine IL-1β and IL-6 mRNA. Rats treated with DCQD had lower mean pathological lung lesion scores than those in SAP rats. Conclusion: DCQD has good prospects in the treatment for SAP because it did shorten the average time that patients suffered ARDS in the clinic. It exerts therapeutic effects on this disease through inhibiting the production of inflammatory mediators, decreasing the anti-inflammatory factors, and mitigating the pathological damage of the lung injury in SAP model. [ABSTRACT FROM AUTHOR]