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The stability analysis of tunnel surrounding rock plays an important role in both engineering design and construction. Jiaoxiling Tunnel is the controlling project of water supply project of Jiaohua Reservoir in Hunan Province. It has the characteristics of complex geological conditions, passing through multiple fault zones, shallow buried sections and broken zones, and rich water layers. Based on the analysis of the engineering geology and hydrogeology of Jiaoxiling Tunnel, this case adopts the method of combining axial strain theory with practice to predict the limit height of spalling and caving of surrounding rock of the tunnel, and then determines the support design of each section of the tunnel. The results show that it is better to determine the thickness of shotcrete and the size of anchor rod according to the type of surrounding rock, and to determine the grouting measures in combination with the groundwater condition. The case results are helpful to provide scientific reference for the design and construction of similar projects. [ABSTRACT FROM AUTHOR]

Background: Coronavirus disease 2019 (COVID-19) is highly contagious and deadly and is associated with coagulopathy. Pentraxin-3(PTX3) participates in innate resistance to infections and plays a role in thrombogenesis. Purpose: The present study aimed to investigate the role of PTX3 in coagulopathy in patients with COVID-19. Methods: A retrospective study, including thirty-nine COVID-19 patients, enrolled in Hunan, China, were performed. The patients were classified into the D-dimer_L (D-dimer<1mg/L) and D-dimer_H (D-dimer=1mg/L) groups basing on the plasma D-dimer levels on admission. Serum PTX3 levels were detected by enzyme-linked immunosorbent assays and compared between those two groups, then receiver operating characteristic (ROC) curve analysis, correlation analysis, and linear regression models were performed to analyze the association between PTX3 and D-dimer. Results: Our results showed that serum PTX3 levels (median values, 10.21 vs. 3.36, P<0.001), computerized chest tomography (C.T.) scores (median values, 10.0 vs. 9.0, P<0.05), and length of stay (LOS) (mean values, 16.0 vs. 10.7, P=0.001) in the D-dimer_H group were significantly higher than that in D-dimer_L group. ROC curve analysis revealed that the AUC of white blood corpuscle counts, C-reaction protein, erythrocyte sedimentation rate, and PTX3 for COVID-19 were 0.685, 0.863, 0.846, and 0.985, respectively. Correlation analysis showed that there was a positive relationship between PTX3 and D-dimer (r=0.721, P<0.001), chest CT imaging score (r=0.418, P=0.008), and LOS (r=0.486, P=0.002). Multiple linear regression analysis showed that the coefficient of determination was 0.657 (P < 0.001). Conclusion: Serum level of PTX3 was positively correlated with disease severity and coagulopathy. Detection of serum PTX3 level could help identify severer patients on admission and may be a potential therapeutic target for coagulopathy in patients with COVID-19. [ABSTRACT FROM AUTHOR]