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Aiming at the effect of principal stress rotation (PSR) in gently inclined coal seam roadways, this study has established a strength criterion that comprehensively considers the coupling effects of multiple factors. Through integrated theoretical analysis, numerical simulation, and physical model testing, this study quantifies the influence of critical parameters on support stability, encompassing principal stress deflection angle, bolt support angle, damage factor, principal stress ratio, and friction coefficient. Quantitative analysis demonstrates that parameter sensitivity exhibits the following hierarchy: damage factor > principal stress deflection angle > principal stress ratio > friction coefficient. The investigation determines optimal roof support angles of 45-55°, with diminished angle sensitivity observed under high dip conditions (ψ ≥ 60°). Digital Image Correlation (DIC) and Electro Mechanical Systems (MEMS) fiber optic sensors were utilized to monitor principal stress rotation, providing high-precision measurements of stress field evolution. This analysis reveals asymmetric PSR distribution characteristics in the roof structure, manifesting rotation angles of 84.23° and 58.45° on the left and right sides respectively. These findings facilitate the development of a regionalized differential support methodology. Field implementation validates the theoretical framework, demonstrating substantial improvements in roadway stability.
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http://dx.doi.org/10.1038/s41598-025-10237-1 | DOI Listing |
J Trace Elem Med Biol
September 2025
Department of Neurology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China. Electronic address:
Objective: We previously documented that exposure to a spectrum of elements is associated with autism spectrum disorder (ASD). However, there is a lack of mechanistic understanding as to how elemental mixtures contribute to the ASD development.
Materials And Methods: Serum and urinary concentrations of 26 elements and six biomarkers of ASD-relevant pathophysiologic pathways including serum HIPK 2, serum p53 protein, urine malondialdehyde (MDA), urine 8-OHdG, serum melatonin, and urine carnitine, were measured in 21 ASD cases and 21 age-matched healthy controls of children aged 6-12 years.
Naturwissenschaften
September 2025
Colorado Water Center, Colorado State University, Fort Collins, CO, 80523, USA.
Drought stress is the most vulnerable abiotic factor affecting plant growth and yield. The use of silicic acid as seed priming treatment is emerging as an effective approach to regulate maize plants susceptibility to water stress. The study was formulated for investigating the effect of silicic acid seed priming treatment in modulating the oxidative defense and key physio-biochemical attributes of maize plants under drought stress conditions.
View Article and Find Full Text PDFEnviron Epidemiol
October 2025
Department of Psychiatry and Behavioral Health, The Ohio State University, Ohio.
Background: Prospective studies suggest that prenatal exposure to chemical neurotoxicants and maternal stress increase risk for psychiatric problems. However, most studies have focused on childhood outcomes, leaving adolescence-a critical period for the emergence or worsening of psychiatric symptoms-relatively understudied. The complexity of prenatal coexposures and adolescent psychiatric comorbidities, particularly among structurally marginalized populations with high exposure burdens, remains poorly understood.
View Article and Find Full Text PDFInt J Numer Method Biomed Eng
September 2025
Department of Industrial and Manufacturing Engineering, Pennsylvania State University, University Park, Pennsylvania, USA.
The screw-retained implant-supported crown is a durable, aesthetic restoration, but debonding between the crown and abutment remains a challenge to survivability. The purpose of this work was to devise an abutment shape that can be embedded into the crown while the crown is being additively manufactured. The result was a mechanically retained, no-adhesive abutment and crown unit that is mounted to the implant fixture.
View Article and Find Full Text PDFRev Sci Instrum
September 2025
Department of Earth Sciences, University College London, London, United Kingdom.
We have developed a new true triaxial apparatus for rock deformation, featuring six servo-controlled loading rams capable of applying maximum stresses of 220 MPa along the two horizontal axes and 400 MPa along the vertical axis to cubic rock samples of 50 mm side. Samples are introduced into a steel vessel, allowing rock specimens to be subjected to confining pressures of up to 60 MPa. Pore fluid lines connected to two pump intensifiers enable high-precision permeability measurements along all three principal stress directions.
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