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Aiming at the problem that the roof of the soft-hard interbedded coal seam is prone to delamination and caving without warning during coal mining, taking the No. 2201 working face of a certain mine as the engineering background, a numerical simulation was carried out to study the mine pressure laws and fracture characteristics of the working face with soft-hard interbedded roof. The results show that: when the working face advances 32 m, the roof undergoes the first caving. The fracture angles of the rock formations on the working face side and the open-off cut side are 50° and 47° respectively, and a stable three-hinged arch structure is formed between the roof and the two sidewalls. The roof rock formations are mainly damaged by tension, and then it evolves into vertical stress of mutual extrusion. The overall fracture and the development of cracks are irregular, resulting in large-amplitude, high-frequency and long-time fluctuations in the working resistance of the supports. The tangential tension of the cracks in the soft rock layer induces the failure of the hard rock layer, and the fracture of the hard rock layer intensifies the damage of the soft rock layer in the reverse direction. The two form a mutual feedback mechanism of failure, making the overall strength of the interbedded roof significantly lower than that of a single hard rock layer. This study reveals the disaster-causing mechanism of the coordinated fracture of the soft-hard interbedded roof, which can provide a theoretical basis for roof control.
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http://dx.doi.org/10.1038/s41598-025-02981-1 | DOI Listing |
Inj Epidemiol
September 2025
Unit of Occupational Medicine, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, SE-171 77, Sweden.
Background: Immigrants continue to face challenges after entering the labor market and remain overrepresented in '3-D jobs' (dirty, difficult, degrading). This study aims to investigate the differences in occupational injury due to accidents (OIA) among immigrants compared to native-born workers in Sweden, and to examine the role of migrant-specific and work factors in these differences.
Methods: This repeated cross-sectional study used nationwide registers including all gainfully employed individuals in 2004-2020 (average annual sample 4.
BMC Public Health
September 2025
Heidelberg Institute of Global Health, Heidelberg University, Bergheimer Str. 20, Zimmer 317, 69115, Heidelberg, Germany.
Background: People living in prison face exceptionally high prevalence rates of tooth decay, periodontal disease, and poor oral health-related quality of life. Despite its importance, various aspects of oral healthcare in prison settings remain understudied. The present study investigates the barriers and facilitators associated with providing and utilizing oral health services in prison settings, drawing on insights from prison health experts, managerial and custodial staff, healthcare providers, and individuals with lived experience of imprisonment.
View Article and Find Full Text PDFEur J Pharm Biopharm
September 2025
Center of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing 210009, China. Electronic address:
Prodrugs with enzymatic activation requirements, such as the weakly basic biopharmaceutical classification system (BCS) class IV compound abiraterone acetate (ABA), face considerable bioequivalence (BE) risks owing to their pH-dependent solubility, food effects, and variable intestinal hydrolysis. This study established clinically relevant dissolution specifications for ABA using biorelevant dissolution and physiologically based biopharmaceutics modelling (PBBM). Two dissolution methods, two-stage (gastrointestinal transfer simulation) and single-phase (biorelevant media), were evaluated under fasted and fed conditions.
View Article and Find Full Text PDFMar Environ Res
September 2025
College of Oceanography and Ecological Science, Shanghai Ocean University, Shanghai, 201306, China. Electronic address:
This review examines the chemical and ecological interactions between filter-feeding mussels and the green macroalga Ulva prolifera in integrated multi-trophic aquaculture (IMTA) systems. Mussels are crucial for nutrient recycling, as they filter water and release bioavailable compounds such as ammonium (NH), urea (CO(NH)), and dissolved organic matter (DOM). These compounds promote Ulva growth and enhance microbial activity.
View Article and Find Full Text PDFAddict Behav
September 2025
School of Education, Fujian Polytechnic Normal University, Fuzhou, China. Electronic address:
Problematic mobile phone use (PMPU) has become increasingly prevalent among young adults, raising concerns about its psychological underpinnings. While shyness has been linked to PMPU, few studies have explored the symptom-level mechanisms that differentiate problematic from non-problematic users. This study employed psychological network analysis to examine the structure and central symptoms of PMPU in two groups: problematic and non-problematic mobile phone users.
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