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For the sake of studying the catastrophe mechanism of stress-fissure coupling field in mining close distance seams in southwest China, a test working face in Guizhou province in southwest China is adopted and researched by the methods of numerical calculation and similar experiment. When the working face advances to 180 m in 4# coal seam in a similar experiment, the overlying rock breaks to the central base plate of Yulongshan limestone, and the conductive fractures run through the Changxing limestone karst cave and Yulongshan limestone karst cave. When the 1402 working face advances to 350 m, the top of vertical karst caves in the middle of the model produces extrusion damage, forming a penetrating water inrush passage. When the 1402 working face advances to 480 m, the top slab of the working face comes under periodic weighting with the short step. Besides, the mining of 9# coal seam starts after 4# coal seam in mining close distance seams. When the working face in 9# coal seam advances to 340 m in numerical simulation, the maximum opening of the overburden fractures is 51.16 mm. The fractures in the roof are mainly caused by the periodic breaking and falling of the basic roof, connected with the floor fractures of 4# coal seam. When the working face in 9# coal seam advances to 500 m, the maximum opening of the overburden fracture is 93.09 mm. Specifically, as the working face advances, the opening of fracture in the roof after collapse of the basic roof periodically is mainly greater than 5 mm, and the compaction closure is mainly 1 mm-5 mm. The fractures in the gob floor are mainly 0.1 mm-1 mm, and the fracture opening of the collapsed rock mass in the gob is mainly 1 mm-5 mm and greater than 5 mm. The karst caves in the overburden reduce the periodic weighting step of working face and play a guiding role in the direction of fracture development and water inflow passage formation. The karst caves are connected to surface waterfall holes and trap pits, and atmospheric precipitation recharges the water in the caves. The research results can be treated as an important basis for the prevention and treatment for water inrush disaster in mining close distance seams in the karst area of southwest China.

Objective: This study investigated the role and mechanisms of 1.25(OH)2D3 in proliferative glomerulonephritis and its effect on the regulation of mesangial cells. Methods: Sixty male SD rats were randomly divided into four groups: control (CG), nephritis (NG), nephritis + 1.25(OH)2D3(NVG), and nephritis + 1.25(OH)2D3+ rapamycin (NVRG) (n = 15 per group). Three rats from each group were sacrificed on days 1, 3, 7, 14, and 21 after intervention. Urine samples were collected over 24 hours on day 0 to measure urinary protein excretion. Renal tissue samples were stained with HE and PAS to evaluate the extent of renal injury, while immunohistochemistry was employed to quantify PCNA and mTOR expression in the renal tissues. Results: Compared to the NG, mesangial cell proliferation in the renal tissues was significantly reduced in the NVG and NVRG at all time points (all p<0.05). PCNA expressionwas significantly higher in the NG compared to the CG (p < 0.05) and significantly lower in the NVG and NVRG (p < 0.05). mTOR expression was also significantly increased in the NG compared to the CG, with a significant reduction observed in the NVG and NVRG compared to the NG. Conclusion: Our findings demonstrate that 1.25(OH)2D3significantly inhibits the proliferation of glomerular mesangial cells in rats. Additionally, mTOR protein is involved in the regulation of glomerular mesangial cells by 1.25(OH)2D3. These results further elucidate the molecular mechanism by which 1.25(OH)2D3alleviates renal injury in glomerulonephritis. [ABSTRACT FROM AUTHOR]

Efficient monitoring and recognition of movement are crucial in enhancing athletic performance. Traditional methods have limitations in terms of high site requirements and power consumption, making them unsuitable for long-term tracking and monitoring. A potential solution to low-power monitoring of body area networks is triboelectric sensors. However, the current analysis method for badminton triboelectric sensing data is relatively simple, while flexible, triboelectric sensors based on 3D printing face issues such as discomfort when joints are bent or twisted in a large range. In light of this, a flexible arch-shaped triboelectric sensor based on 3D printing (FA-Sensor) is proposed. By combining neural network algorithms with the signal acquisition module and the master computer, an intelligent multi-sensor node system for badminton monitoring is established. The FA-Sensor exhibits high sensitivity to bending and twisting motions due to its elastic TPE shell and arched shape design. It minimizes interference with human motion during bending (10°–150°) or twisting (20°–100°) over a wide range. The peak output voltage of the FA-Sensor demonstrates a clear functional relationship with the bending angle, exhibiting piecewise sensitivities of 7.98 and 29.28 mV/°, respectively. For seven different parts of the human body, it can be quickly customized to different sizes, with stable and repeatable response outputs. In application, the badminton sports monitoring system enables real-time feedback and recognition of four typical technical movements, achieving a recognition accuracy rate of 97.2%. The system enables athletes to analyze and enhance badminton technology while also exhibiting promising potential for application in other intelligent sports domains. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the role and mechanisms of 1.25(OH)2D3 in proliferative glomerulonephritis and its effect on the regulation of mesangial cells., Methods: Sixty male SD rats were randomly divided into four groups: control (CG), nephritis (NG), nephritis + 1.25(OH)2D3(NVG), and nephritis + 1.25(OH)2D3+ rapamycin (NVRG) (n = 15 per group). Three rats from each group were sacrificed on days 1, 3, 7, 14, and 21 after intervention. Urine samples were collected over 24 hours on day 0 to measure urinary protein excretion. Renal tissue samples were stained with HE and PAS to evaluate the extent of renal injury, while immunohistochemistry was employed to quantify PCNA and mTOR expression in the renal tissues., Results: Compared to the NG, mesangial cell proliferation in the renal tissues was significantly reduced in the NVG and NVRG at all time points (all p<0.05). PCNA expressionwas significantly higher in the NG compared to the CG (p < 0.05) and significantly lower in the NVG and NVRG (p < 0.05). mTOR expression was also significantly increased in the NG compared to the CG, with a significant reduction observed in the NVG and NVRG compared to the NG., Conclusion: Our findings demonstrate that 1.25(OH)2D3significantly inhibits the proliferation of glomerular mesangial cells in rats. Additionally, mTOR protein is involved in the regulation of glomerular mesangial cells by 1.25(OH)2D3. These results further elucidate the molecular mechanism by which 1.25(OH)2D3alleviates renal injury in glomerulonephritis., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Li et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)