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To explore the hazard zone of coal spontaneous combustion in the adiacent goaf at different stages of the roadway driving face, the 2202 working face and the 2201 adjacent goaf of Yingpanhao Coal Mine were taken as examples. The large-scale experiment was conducted to analyze the coal spontaneous combustion limit parameters of the 2201 goaf. The conditions for identifying the hazard zone of coal spontaneous combustion in the adjacent goaf were proposed. Monitoring the gas concentration and temperature in 2201 adjcent goaf by the drilling holes through coal pillar, and the numerical simulation was conducted to study the oxygen concentration distribution in 2201 adjcent goaf, and the hazard zone of coal spontaneous combustion in the adjacent goaf was obtained. The results show that during the mining period of the 2202 working face, the coal pillar was broken by the stress concentration, and the oxygen volume fraction of the adjacent goaf was in the range of 10.1% to 13.8%. The oxygen volume fraction of the adjacent goaf before the stop mining period was between 10.3% and 15%. During the mining period, a narrow area on the coal pillar side with width 55 m from the front 45 m and behind 119 m of 2202 working face in the adjacent goaf was the coal spontaneous combustion hazard zone. Before the stop mining period, a narrow area on the coal pillar side with width 42 m from the front 63 m and behind 107 m of 2202 working face in the adjcent goaf was in an oxidizing environment.

Background: With rising breast augmentations worldwide, there is an increasing clinical need for an early and accurate detection of implant complications. Purpose: To compare the quality of chemical shift encoding-based (CSE) water-fat-silicone separation compared to double inversion recovery (DIR) silicone-only imaging in breast magnetic resonance imaging (MRI). Material and Methods: This retrospective, single-center study included women with silicone implants subjected to 3-T MRI between January 2021 and March 2022. MRI included (i) two-dimensional silicone-only T2-weighted turbo spin echo DIR acquisition and (ii) three-dimensional CSE imaging based on multi-echo gradient-echo sequence enabling water-, fat-, and silicone-image separation. Images were evaluated and compared by three independent radiologists using a clinically established rating including differentiability of the silicone implant, visibility and contouring of the adjacent fibrous capsule, and accuracy of intralesional folds in a ranking of 1–5. The apparent contrast-to-noise (aCNR) was calculated. Results: In 71 women, the average quality of water-fat-silicone images from CSE imaging was assessed as "good" (assessment 4 ± 0.9). In 68 (96%) patients, CSE imaging achieved a concise delineation of the silicone implant and precise visualization of the fibrous capsule that was not distinguishable in DIR imaging. Implant ruptures were more easily detected in CSE imaging. The aCNR was higher in CSE compared to DIR imaging (18.43 ± 9.8 vs. 14.73 ± 2.5; P = 0.002). Conclusion: Intrinsically co-registered water-fat-silicone-separated CSE-based images enable a reliable assessment of silicone implants. The simultaneously improved differentiability of the implant and fibrous capsule may provide clinicians with a valuable tool for an accurate evaluation of implant integrity and early detection of potential complications. [ABSTRACT FROM AUTHOR]

Fire area isolation is the main method to effectively control the development and spread of fire, which can cut off the reaction chain of secondary accidents and reduce the scope of fire impact. In order to solve the problem that the commonly used fire airtight isolation measures cannot provide real-time dynamic monitoring and forecasting of the airtight environment, a dynamic information perception and emergency isolation system for mine fire environment is designed. The monitoring nodes are arranged in the predetermined dangerous areas, and the environmental information of multiple measuring points are collected and transmitted to the ground monitoring platform through multi-parameter sensors and infrared cameras. When abnormal data is detected, the system alarms and controls the airtight isolation device to open through remote control to realize the airtight bag filling. The bag is expanded from the storage bin to the entire section through the preset slide rail drive system to realize emergency airtight isolation. Real-time monitoring of the internal air pressure of the bag is carried out through high-precision pressure sensors. When the internal pressure of the bag is lower than the lower limit of the safety range, the automatic air-filling device of the bag is activated to replenish the air volume of the bag. When the internal pressure reaches the upper limit of the set range, the device automatically stop inflation to enhance the airtight effect. Field test results show that the system achieves the functions of real-time collection and alarm of fire environment parameters, remote control of airtight isolation device, etc. The airtight bag can be opened within 5 min, and the pressure inside the airtight bag remains basically stable after stopping inflation, which meets the requirements of field applications.

Salinity stress has a great impact on crop growth and productivity and is one of the major factors responsible for crop yield losses. The K-homologous (KH) family proteins play vital roles in regulating plant development and responding to abiotic stress in plants. However, the systematic characterization of the KH family in rice is still lacking. In this study, we performed genome-wide identification and functional analysis of KH family genes and identified a total of 31 KH genes in rice. According to the homologs of KH genes in Arabidopsis thaliana, we constructed a phylogenetic tree with 61 KH genes containing 31 KH genes in Oryza sativa and 30 KH genes in Arabidopsis thaliana and separated them into three major groups. In silico tissue expression analysis showed that the OsKH genes are constitutively expressed. The qRT-PCR results revealed that eight OsKH genes responded strongly to salt stresses, and OsKH12 exhibited the strongest decrease in expression level, which was selected for further study. We generated the Oskh12-knockout mutant via the CRISPR/Cas9 genome-editing method. Further stress treatment and biochemical assays confirmed that Oskh12 mutant was more salt-sensitive than Nip and the expression of several key salt-tolerant genes in Oskh12 was significantly reduced. Taken together, our results shed light on the understanding of the KH family and provide a theoretical basis for future abiotic stress studies in rice. [ABSTRACT FROM AUTHOR]

High‐performance and durable membranes are being sought to enable energy‐efficient CO2 capture. Although representing an appealing candidate for the above application, successful translation of distinct properties of MOF filler into hybrid composite membranes (HCMs) remains challenging. In this study, we synthesized uniform hollow defect‐engineered UiO‐66 nanoparticles as filler for enhancing the CO2/N2 separation performance and durability of Pebax‐2533 membranes. The existence of missing‐linker defects in the framework not only endows HCMs with higher CO2/N2 adsorption selectivity but also provides ultrafast CO2 transport pathways; moreover, hollow structure of UiO‐66 not only contributes to better filler dispersibility in polymeric matrix but also reduces CO2 diffusion path length. Obtained HCMs manifest concurrently increased CO2 permeability (3100 Barrer) and CO2/N2 separation factor (44), far exceeding state‐of‐the‐art 2019 upper bound for polymer membranes; moreover, our membranes exhibit enhanced resistance toward plasticization, physical aging, and water vapors under harsh operation conditions. [ABSTRACT FROM AUTHOR]

Zeolitic Imidazolate Framework‐8 (ZIF‐8) membrane is well recognized for its great capability in efficient C3H6/C3H8 separation, and their sustainable fabrication is extremely advantageous for batch production and commercial application. In this study, a solvent‐free protocol was developed for sustainable production of ZIF‐8 membranes with exceptional C3H6/C3H8 selectivity through combining atomic layer deposition (ALD) technique with in situ supercritical fluid (SCF) processing. Experimental results indicated that maintaining appropriate deposition number and conducting SCF processing in gas‐like supercritical carbon dioxide region were crucial for obtaining ZIF‐8 membranes with excellent C3H6/C3H8 selectivity (~185), one of the highest among ZIF‐8 membranes reported in the literature. Noteworthy, not only residual 2‐methylimidazole ligands along with vented gaseous CO2 could be fully recycled and repetitively utilized, but also obsoleting ZIF‐8 membranes could be effectively patched upon SCF‐based treatment. The above‐mentioned solvent‐free protocol holds great application prospects for sustainable production of diverse high‐performance metal–organic framework membranes. [ABSTRACT FROM AUTHOR]

The importance of bioink suitability for extrusion bioprinting tissue‐like constructs cannot be overemphasized. Owing to their excellent accessibility, alginate (Alg) ‐based bioinks are widely used. However, the printability accuracy and post‐printing stability of current Alg‐based bioinks remain challenging, especially for large‐size fabrication. Herein, an improvement strategy for pre‐crosslinking and post‐crosslinking of methacrylated Alg (AlgMA) bioinks in extrusion bioprinting is presented via introduction of methacrylated ɛ‐polylysine (ɛ‐PLMA) as a small‐molecule polycationic crosslinker. Due to their electrostatic interaction and covalent bonding, ɛ‐PLMA significantly reinforce the operability and prolong stability of AlgMA bioinks, in comparison with single‐molecule Ca2+ or large‐molecule methacrylated gelatin as pre‐crosslinkers. Meanwhile, attributed to their regulation of a charged microenvironment (−345.25 to 121.55 mV) and hydrophilicity (26.64° to 52.00°), the cells in bioprinted AlgMA/PLMA constructs demonstrated improved viability and vitality. Therefore, such a strategy of introducing small‐molecule cationic crosslinker ɛ‐PLMA is a promising booster for improving Alg‐based extrusion bioprinting, potential to extend its biomedical applications. [ABSTRACT FROM AUTHOR]

ZMIZ1 acts as an oncogene in hepatocellular carcinoma (HCC). circZMIZ1 (hsa_circ_0018964) derives from ZMIZ1; its underlying mechanism in HCC has not been reported. Peripheral blood and peripheral blood mononuclear cells (PBMCs) were obtained from HCC patients and healthy volunteers. CD8+ T cells were sorted from PBMCs of HCC patients. Applying flow cytometry, cell apoptosis and the proportion of KCNJ2/CD8+ T cells were examined. The cytotoxicity of CD8+ T cells against HCC cells was evaluated. The interaction among circZMIZ1, miR-15a-5p, and KCNJ2 was investigated by dual luciferase assay, RNA immunoprecipitation, and RNA pull-down assay. An orthotopic mouse model of HCC was constructed by intrahepatic injection of H22 cells. Upregulation of circZMIZ1 and KCNJ2 and downregulation of miR-15a-5p were observed in peripheral blood and PBMCs of HCC patients. The proportion of KCNJ2/CD8+ T cells was also increased in HCC patients. circZMIZ1 knockdown restrained apoptosis of CD8+ T cells and elevated cytotoxicity of CD8+ T cells. Mechanically speaking, circZMIZ1 elevated KCNJ2 expression by sponging miR-15a-5p. miR-15a-5p inhibitor reversed circZMIZ1 silencing-mediated inhibition of apoptosis and promotion of cytotoxicity in CD8+ T cells. In vivo, orthotopic mice of HCC exhibited increased expression of circZMIZ1 and KCNJ2, elevated proportion of KCNJ2/CD8+ T cells, and decreased expression of miR-15a-5p. This work demonstrated that circZMIZ1 inhibited the anti-tumor activity of CD8+ T cells in HCC by regulating the miR-15a-5p/KCNJ2 axis. This provides a theoretical basis for the development of effective circZMIZ1 in tumor immunotherapy. [ABSTRACT FROM AUTHOR]

An anisotropic egg-shaped bounding surface plasticity model (AESBS model) is proposed to describe cyclic and monotonic behaviors of saturated clays. The model is based on an innovative egg-shaped bounding surface, which not only eliminates the singularity present in most plasticity models and facilitates numerical calculation but also can be degenerated into various configurations. Moreover, to improve its representation when considering the initial consolidated state, an anisotropic tensor is incorporated into the bounding surface. Furthermore, a novel generalized isotropic hardening rule that combines isotropic and kinematic hardening is applied. It regards reversal stress points as homological mapping centers, hence leading to discrete and movable mapping centers. Notably, the elastic zone concept is employed to produce a more realistic performance of nonlinearity during cyclic loading. These modifications formulate the novel model that can be utilized to enhance the ability in predicting the behavior of saturated clays. To improve the convergence of the model, an implicit integration scheme is used to solved the constitutive relationship through some nonlinear algebraic equations. The comparison of simulation results and published experimental data from one-way undrained cyclic and monotonic triaxial tests for saturated clays demonstrates the efficiency of this model under different consolidated conditions. [ABSTRACT FROM AUTHOR]