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The deformation damage and support difficulties caused by the formation and expansion of plastic zone of surrounding rock have always been urgent engineering problems to be solved, especially in areas with prominent non-uniform stress fields. Choosing a reasonable and practical method to determine the plastic zone is of great significance for ensuring the long-term stability and safety of tunnels. Based on a tunnel project in the southwest mountainous area, this paper conducted mechanical tests to obtain the mechanical parameters of granite. The analytical method optimized based on the principle of stress balance was applied, and the numerical simulation was carried out according to the field displacement monitoring data and experimental parameters, the plastic zone of the medium quality granite cross-section and fault fracture zone granite cross-section was analyzed comprehensively. The results shown that the analytical and numerical solutions are in good agreement with engineering practice. It proved that the theory and method in this paper are scientific and practical in engineering. The research results can provide support for the design optimization and construction safety of the tunnel, and the research ideas and methods can also provide reference for similar projects. [ABSTRACT FROM AUTHOR]

Numerous studies have examined the relationship between childhood maltreatment (CM) and nonsuicidal self-injury (NSSI). However, few studies have explored both the specific and cumulative effects of CM on NSSI. Additionally, the impact of sleep disturbance on the association between CM and NSSI remains unclear. To comprehensively explore the effects of CM on NSSI, and to determine whether these effects are moderated by sleep disturbance. A retrospective study was conducted in April 2021 among a representative sample of 21,340 students aged 11–20 years in China. All participants completed questionnaires assessing CM, sleep disturbance, and NSSI. Adjusted multivariate logistic regression models were utilized to evaluate the associations between CM and NSSI, as well as the impact of sleep disturbance. The findings revealed that 13.0 % of adolescents reported occasional NSSI, while 25.2 % reported repetitive NSSI. Except for sexual abuse, all subtypes of CM were significantly associated with increased odds of both occasional and repetitive NSSI. A significant dose-response relationship was observed between cumulative CM and repetitive NSSI. Stratification analyses by sleep disturbance indicated that adolescents reporting sleep disturbance had a higher risk of developing repetitive NSSI, irrespective of the type of CM experienced. Furthermore, a dose-response relationship was identified between cumulative CM and repetitive NSSI among adolescents reporting sleep disturbance. This study demonstrated that CM increases the risk of NSSI among Chinese adolescents, and sleep disturbance plays a moderating role. Interventions targeting sleep disturbance may hold significance in reducing NSSI. • All subtypes of CM were found to be significantly associated with repetitive NSSI, but not with occasional NSSI. • CCM was associated with repetitive NSSI in a dose-response way, which was not observed in occasional NSSI. • Sleep disturbance was significantly associated with an increased risk of NSSI, with a higher OR for repetitive NSSI. • Sleep disturbance moderated the relationships between CM and NSSI. [ABSTRACT FROM AUTHOR]

• Both PSU and E-type plays a prominent role in increasing the risk of NSSI among Chinese adolescents. • PSU and chronotype had an interaction effect on NSSI. • Gender differences were found in the independent and interaction effects of PSU and chronotype on NSSI. Nonsuicidal self-injury (NSSI) is a serious public health and clinical problem, particularly for adolescents, and may link to problematic smartphone use (PSU) and chronotype. This study examines the independent and interaction effects of PSU and chronotype on NSSI among adolescents and identified gender differences in these associations. A total of 21,357 students aged 11–19 were recruited using stratified cluster sampling across five representative provinces in China and completed standard questionnaires to record details of PSU, chronotype, and NSSI. A total of 38.1 % of students reported having engaged in NSSI and 17.7 % had PSU. PSU and chronotype were significantly associated with NSSI among adolescents, and this relationship was stronger in females. Interaction analysis indicated that E-type and PSU were interactively associated with increased risks of NSSI. The findings suggest that E-type and PSU can increase the risk of NSSI both independently and interactively. Therefore, they should be considered in intervention programs for NSSI, especially for females. [ABSTRACT FROM AUTHOR]

Many left-behind children (LBC) are emerging in rural China and growing evidence indicated that parental migration was associated with various psychological problems. However, little is known about Internet addiction and suicidal behaviors among LBC. The study aims to explore the effect of Internet addiction and parental migration on three stages of suicidal behaviors, including suicidal ideation (SI), suicide plans (SP), and suicide attempts (SA). A total of 15,232 students graded 7 to 12 were recruited across five representative provinces in China. Results showed that LBC had a higher prevalence of SI and SA than non-LBC. However, after controlling for confounders, parental migration was insignificantly associated with suicidal behaviors. Internet addiction was significantly associated with increased odds of SI, SP, and SA. In addition, some variables showed different effects on suicidal behavior between LBC and non-LBC. Among LBC, psychological resilience, emotion management, and social support were negatively while loneliness was positively associated with SI, SP, and SA. Our findings suggest that adolescents with Internet addiction are more likely to report suicidal behaviors in rural China. For LBC, suicide preventive strategies could focus on reducing problematic Internet use and loneliness as well as improving psychological resilience, emotion management, and social support. • Left-behind children (LBC) showed significantly higher prevalence of suicidal ideation and suicide attempts than non-LBC. • Parental migration was not the risk factor of suicidal behaviors after controlling for confounders. • Internet addiction was a robust risk factor of suicidal behaviors, with or without the effect of parental migration. [ABSTRACT FROM AUTHOR]

Gas seepage and progressive failure of coal are common energy-driven mining phenomena. A comprehensive understanding of the energy-driving mechanism behind the catastrophic behavior of mining-induced coal is fundamental to innovating the technology of coal and gas co-mining. Thus, this study simulated three typical mining stress evolution process in protective coal-seam mining (PCM), top-coal caving mining (TCM), and non-pillar mining (NM) to investigate the energy evolution and distribution patterns of coal. The results indicate a strong correlation between energy dissipation and gas seepage. By transitioning from PCM and TCM to NM, the peak elastic strain energy of gas-bearing coal increased by 155.92 %, and the ratio of peak dissipative energy decreased from 51 % to 41 %. Under the PCM stress path, gas seepage decreased the energy storage by 13.52 %, whereas the pre-mining pressure relief and enhanced permeability simulation increased in peak dissipation energy by 49.66 %. Using the cumulative dissipative energy as a damage variable reveals that the degree of coal damage evolution under PCM is higher than other mining methods. Based on the energy-driven damage mechanism, a new coal permeability model was established, and its comparison with classical permeability model demonstrated its excellent fitting effectiveness. [ABSTRACT FROM AUTHOR]