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Fault coal bursts is a common type of coal bursts in coal mining. With increases in mining depths and mining intensities, the occurrence frequency and disaster degree of coal bursts in fault‐controlled areas are increasing in severity. Therefore, in this article, the mechanism and control method of deep mining‐induced fault coal bursts are analysed on the No. 3402 longwall panel controlled by two faults in the Shandong Mine, China. Based on the microseismic monitoring data of the longwall panel, the fault activation process induced by mining can be divided into four stages. The second energy release and fault activation stages are risk stages of fault coal bursts. Using numerical simulation, the evolution laws of vertical stress, elastic strain energy in front of the longwall panel, and the ratio of shear stress to normal stress on fault plane are investigated. The phenomenon of a 'high elastic energy section‐low elastic energy section' coal pillar between faults is revealed, and the mechanism of coal pillar coal bursts induced by high elastic energy is discussed. Third, based on the above research results, coal burts risk areas of the longwall panel in the fault‐controlled area are determined. The method of 'coal seam‐roof‐floor coupling destressing with the reduction in mining speed' to control fault coal bursts is introduced. Field test results show that the method effectively destroys the integrity and bearing capacity of the coal seam, significantly reduces the energy storage capacity of the superposition area of mining stress and fault tectonic stress, so that the coal bursts risk of the coal seam in the fault control area is relieved, ensuring safe and efficient mining of the longwall panel. The method can provide a reference for other coal mines with similar geological conditions. [ABSTRACT FROM AUTHOR]

Background: To explore the kinetic changes in virology, specific antibody response and imaging during the clinical course of COVID-19.Methods: This observational study enrolled 20 patients with COVID-19, who were hospitalized between January 20-April 6, 2020, in the two COVID-19 designated hospitals of Zhoushan, Zhejiang and Rushan, Shandong, China, The laboratory findings, imaging, serum response to viral infection, and viral RNA level in the throat and stool samples were assessed from onset to recovery phase in patients with COVID-19.Results: SARS-COV-2 RNA was positive as early as day four. It remained positive until day 55 post-onset in the sputum-throat swabs and became negative in most cases (55%) within 14 days after onset. Lymphocytopenia occurred in 40% (8/20) of patients during the peak infection period and returned to normal at week five. The most severe inflammation in the lungs appeared in week 2 or 3 after onset, and this was completely absorbed between week 6 and 8 in 85.7% of patients. All patients had detectable antibodies to the receptor binding domain (RBD), and 95% of these patients had IgG to viral N proteins. The antibody titer peaked at week four. Anti-S IgM was positive in 7 of 20 patients after week three.Conclusions: All COVID-19 patients in this study were self-limiting and recovered well though it may take as long as 6-8 weeks. Our findings on the kinetic changes in imaging, serum response to viral infection and viral RNA level may help understand pathogenesis and define clinical course of COVID-19. [ABSTRACT FROM AUTHOR]