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The stability of coal walls (pillars) can be seriously undermined by diverse in-situ dynamic disturbances. Based on a 3D particle model, this work strives to numerically replicate the major mechanical responses and acoustic emission (AE) behaviors of coal samples under multi-stage compressive cyclic loading with different loading and unloading rates, which is termed differential cyclic loading (DCL). A Weibull-distribution-based model with heterogeneous bond strengths is constructed by both considering the stress–strain relations and AE parameters. Six previously loaded samples were respectively grouped to indicate two DCL regimes, the damage mechanisms for the two groups are explicitly characterized via the time-stress-dependent variation of bond size multiplier, and it is found the two regimes correlate with distinct damage patterns, which involves the competition between stiffness hardening and softening. The numerical b-value is calculated based on the magnitudes of AE energy, the results show that both stress level and bond radius multiplier can impact the numerical b-value. The proposed numerical model succeeds in replicating the stress–strain relations of lab data as well as the elastic-after effect in DCL tests. The effect of damping on energy dissipation and phase shift in numerical model is summarized. Highlights: Fatigue behaviors of coal are reproduced by particle model under DCL Micro seismic monitoring is implemented based on heterogeneous particle model The distinction incurred by DCL is reproduced and revealed [ABSTRACT FROM AUTHOR]

Chen et al. [[6]] developed a method to obtain the size distribution characteristics of the real source from the apparent amplitude in doubly truncated distribution using rock acoustic emission (AE) tests. 10.3390/math10193490 9 Qiu J., Feng F. Effect of Different Tunnel Distribution on Dynamic Behavior and Damage Characteristics of Non-Adjacent Tunnel Triggered by Blasting Disturbance. With the increasing requirements for energy, resources and space, numerous rock engineering projects (e.g., mining, tunnelling, underground storage, geothermal energy, petroleum, water conservancy and hydropower) are more often being constructed and operated in large-scale environments with complex geology. [Extracted from the article]

The shale fracture permeability is critical in determining gas production and deep CO2 sequestration performance. Moreover, how shale fracture permeability evolves after interactions with supercritical carbon dioxide (Sc-CO2) should be understood to constrain the shale reservoir permeability and evaluate the long-term sealing ability of shale formations. In this research, we conducted soaking experiments with shale fractures and Sc-CO2 at various times and then measured the shale fracture permeability and hydraulic aperture evolution under different stress states. Additionally, we quantify the chemical compositions, pore characteristics, fracture surface roughness alternation through X-ray diffraction, nuclear magnetic resonance, scanning electron microscope, and optical profilometry techniques. Our results indicate that soaking with Sc-CO2 will dramatically increase the shale fracture permeability and aperture due to the calcite and dolomite dissolution. This free-face dissolution process will remove the mineral particles in the fracture surface, resulting in larger pores, peaks, and valleys in the fracture surfaces. This process may last for seven days, and after that, chemical reactions may terminate, and the rock-Sc-CO2 system turns stable. Our results explain how Sc-CO2 alters the shale fracture permeability through the chemical dissolution of specific minerals from a microscale analysis. [ABSTRACT FROM AUTHOR]

Background: Myelomatous pleural effusion (MPE), as a presentation of extramedullary infiltration of multiple myeloma (MM), is rare and currently associated with poor outcomes without effective therapy. The potential value of cytokine detection in pleural effusion to MPE has not been reported to date. Case Presentation: We herein report a case of refractory and relapsed multiple myeloma that developed bilateral MPE due to disease progression caused by intolerance to various chemotherapy regimens. Cytomorphology and flow cytometry were adopted for diagnosis confirmation. Chemotherapy containing immunomodulators combined with thoracic catheterization drainage was applied to the patient, showing a certain therapeutic effect. During the course of disease, the change of cytokine profile in pleural effusion was monitored by cytometric bead array (CBA) technology, revealing that cytokines related to tumor load such as interleukin 6 (IL-6) and interleukin 10 (IL-10) in pleural effusion decreased with the improvement of disease, while other cytokines such as interleukin 2 (IL-2), interleukin 4 (IL-4), interleukin 17A (IL-17A), tumor necrosis factor α (TNF-α), interferon γ (IFN-γ), granzyme A, granzyme B, perforin and granulysin increased with the improvement of disease. Conclusion: There is a prospect that cytokine level in pleural effusion may indicate treatment response of MPE, and in light of this case, immunomodulators may be utilized in treating patients suffering MPE. Due to limitations of our single case, we urge more groups to evaluate the potential role of cytokine profile in MPE. [ABSTRACT FROM AUTHOR]