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Abstract Mine gas explosion causes serious failure (damage) to the roadway, but the research on the response characteristics of the impact load of gas explosion to the roadway wall are still very limited. In view of the shortcomings of the existing research, the LS‐DYNA software is used to establish the physical and mathematical models of gas explosion in a roadway, and the validation results show that the model is effective and reliable. Based on the model, changes of pressure, velocity, displacement of roadway walls and equivalent stress under the impact of gas explosions are measured. The response characteristics of the end and wall of roadway under the thermal impact of gas explosion are analyzed. The results show that the pressure on the closed end wall, the center and edge of the roadway is relatively large, and the wall failure is also relatively more serious. With the propagation of gas explosion, the overpressure on the closed end wall gradually attenuates, and the maximum overpressure region also retracts to the center. At the closed end, the explosion pressure is first loaded on the inner wall and gradually transferred to the outer wall. During the transfer, the pressure decays step by step, and the velocity of the measuring point at the closed end decays continuously. With the propagation of gas explosion, the displacement of each measuring point in the Z direction increases continuously. In the axial direction, the displacement near the center of the roadway is large, and then the displacement decreases in the form of regular rings. The impact load produced by the gas explosion is first loaded onto the closed end wall, resulting in wall deformation and equivalent stress. The study results can provide some theoretical basis and data support for the roadway wall design, and reduction of the wall failure.

During the process of mining underground coal, the coal emits a large amount of methane into the mining space, which may lead to methane accumulation and exceed explosion safety limits When the methane encounters a fire source, a methane explosion may occur. The forceful impact caused by a methane explosion in an underground roadway can cause serious damage to the roadway structures and even lead to the collapse of the ventilation system. At the same time, the explosion impact may result in the death of workers and cause physical injury to the surviving workers. Therefore, it is necessary to study the damage effect and injury range of methane explosions. On the basis of the damage criteria and damage characteristics of methane explosions, according to the overpressure distribution of shock waves in the propagation process of a methane explosion, the explosion hazard range is divided into four ranges (from inside to outside): death range, serious injury range, minor injury range, and safety range. Four injury degrees of shock wave overpressure to personal body (slight, medium, serious injury, death), and seven damage degrees of overpressure to structures are also analyzed. The thresholds of their damage (destruction) are determined. On this basis, an experimental system and numerical simulation are constructed to measure damage characteristics, the overpressure value, and the range distance of a methane explosion with different initial explosion intensities. According to the experimental and numerical results, the attenuation formula of a methane explosion shock wave in the propagation process is derived. The research results show that the overpressure and impulse of shock waves are selected as the damage criteria for comprehensive evaluation, and the overpressure criterion is suitable of determining the injury (failure) range over long distances. The four injury ranges are in line with the actual situation and are reasonable. The injury degree also conforms to the medical results, which can be used to guide the injury degree of mine methane explosions. The injury range caused by methane explosions with different initial explosion intensities is reasonable and is basically consistent with the on-site situation. The derived attenuation formula and calculated safety distance are in good agreement with the experimental and numerical results. The research results can provide guidance and help in the escape, rescue, and protection of coal mine underground person. [ABSTRACT FROM AUTHOR]

Background and purpose: Colorectal cancer is one of the most common malignancies. The efficacy of 5-fluorouracil (5-FU) in the treatment of colorectal cancer is often affected by drug resistance or toxic side effects. Dihydropyrimidine dehydrogenase (DPD) is the key enzyme in the metabolism of 5-FU, and the expression or degradation rate of 5-FU may be a factor affecting the efficacy of 5-FU. Autophagy is an important pathway of intracellular protein degradation. This study aimed to detect the expression of microtubule-associated protein light chain 3 (LC3), P62 and DPD in colorectal cancer, and to explore their correlation and clinical significance, so as to provide a new way to reverse 5-FU resistance. Methods: Immunohistochemical envision method was used to detect the expressions of LC3, p62 and DPD in 157 colorectal cancer paraffin tissues archived by Department of Pathology, Binzhou Medical University Hospital from 2013 to 2014. Western blot and real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) were used to detect the expressions of LC3, p62 and DPD in 44 colorectal cancer fresh tissues received by Department of Pathology, Binzhou Medical University Hospital in 2020. The correlation and clinical significance were analyzed. Results: The expressions of LC3, P62 and DPD were significantly higher in colorectal carcinoma than in normal tissues (P0.05). The expression of P62 was positively correlated with T stage and lymph node metastasis. The expression of LC3 was positively correlated with tumor size and T stage. The protein expression of DPD was closely related to histological type (P

ABSTRACT Wheat is a crucial food crop, yet its production is continually threatened by abiotic stresses, particularly salt stress. Understanding the molecular mechanisms by which wheat responds to salt stress is essential for developing salt‐tolerant varieties. In this study, we investigated the molecular pathway involving the wheat TaDHN7 in response to salt stress. The overexpression of TaDHN7 enhances salt tolerance and reactive oxygen species (ROS) scavenging in wheat, while the knockout of TaDHN7 significantly impairs salt tolerance. Furthermore, we identified that TaWRKY44 promotes the expression of TaDHN7 by binding to the W‐box within the TaDHN7 promoter. Additionally, TaWRKY17 interacts with TaWRKY44, and this interaction enhances the protein stability of TaWRKY44 under salt stress, thereby enhancing its transcriptional regulatory capacity on TaDHN7. This study elucidates the TaWRKY17‐TaWRKY44‐TaDHN7 pathway in response to salt stress in wheat, providing valuable insights for the development of salt‐tolerant wheat cultivars. [ABSTRACT FROM AUTHOR]

To further investigate the propagation characteristics of shock waves and flame waves in H‐type tunnel gas explosions, numerical simulation studies were conducted on a dual‐source gas explosion model using Fluent software. Three distinct operational conditions were designed and modeled, leading to the following outcomes. The shock wave flow field parameters from dual sources (with equal source energy) are symmetrically distributed in the H‐type tunnel, with high pressure and low flow velocity in the connecting roadway between the two shock waves. Under different conditions, the pressure is generally higher in closed tunnels (fully closed greater than semi‐closed) and lower in open tunnels. The largest overpressure in non‐explosion areas occurs at the closed ends and in the connecting roadway, while the areas bearing the greatest impulse are the shock wave reflection zones and pressure coupling regions. In closed conditions, the flame wave first moves forward and then propagates backward after the explosion, influenced by reflected waves and pressure differences between the ends and the tunnel. In open conditions, the pressure in the flame zone is lower than at both ends, inhibiting the forward propagation of the flame wave. [ABSTRACT FROM AUTHOR]

Aims/Background Hematospermia, characterized by blood in the ejaculate, is a common and distressing condition in urology. Identifying the underlying causes, including translucent membranes in the prostatic utricle, is crucial for effective management. Despite advancements in diagnostic techniques, reliable predictive tools are needed to enhance preoperative planning and patient outcomes. This study aimed to develop a novel nomogram to predict the presence of translucent membranes in the prostatic utricle of hematospermia patients. Methods In total, 284 patients were selected from The Second People's Hospital of Hefei database based on inclusion and exclusion criteria. The cohort was divided into a training set (198 patients) and a validation set (86 patients). To identify risk factors associated with the prostatic utricle translucent membrane, multivariable logistic regression analysis was employed. The identified risk factors were then used to construct a predictive nomogram model. The performance of the nomogram was evaluated using several statistical tools: receiver operating characteristic (ROC) curves to assess discriminative ability, calibration curves to evaluate prediction accuracy, and decision curve analysis (DCA) to determine clinical utility. Results The findings revealed that age, duration of disease, history of seminal vesiculitis, and seminal vesicle dimensions (width, length, and thickness) were independent risk factors for the presence of a prostatic utricle translucent membrane in patients with hematospermia. Using these variables, a nomogram was developed. The nomogram demonstrated strong predictive capability, as evidenced by its performance in ROC and calibration curve analyses. Furthermore, the DCA indicated that the nomogram offered significant clinical net benefits in predicting the presence of a translucent membrane. Conclusion Clinical use of the developed nomogram can assist clinicians in identifying patients with hematospermia who have translucent membrane in the prostatic utricle and in developing individualized treatment. [ABSTRACT FROM AUTHOR]

To investigate the changes in conditions within a blind roadway when multiple gas explosion sources are simultaneously detonated, the fluid dynamics software Fluent14.0 was used to conduct numerical simulation experiments with different numbers (2 and 3) and varying intervals (5 m, 10 m, and 15 m) of explosion sources. The results revealed that multiple explosion sources in gas explosions generate shock waves that propagate in opposite directions, creating pressure overlap zones within the roadway. The pressure waves and shock waves in these overlap zones continuously couple within the roadway. The number of overlap zones decreases incrementally with each encounter of opposing shock waves in the roadway. Unlike single explosion source models, the pressure at various positions within the roadway in multiple explosion source models oscillates due to the coupling of multiple shock waves, with significant peak pressures occurring at the closed end of the roadway and in the pressure overlap zones. Additionally, the propagation patterns of shock waves and flames within the roadway are not associated with the interval distance between explosion sources, whereas the encounter time, speed, and pressure of shock waves increase with the interval distance. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of initial pressures on the propagation characteristics of gas explosion in roadway, the physical model of gas explosion under different initial pressures in roadway is established by the fluid-structure interaction algorithm of ANSYS/LS-DYNA. The pressure of shock wave, the rise rate of pressure and the flame propagation velocity are analyzed when the initial pressure is 0.08, 0.09, 0.10, 0.11, and 0.12 MPa, respectively. The results reveal that the maximum pressure of shock wave at the same position in the roadway increases significantly with the increase of initial pressure, which presents a quadratic function relationship. The time to reach the maximum pressure of shock wave is extended comparatively. In addition, the maximum rise rate of shock wave pressure increases with the increase of the initial pressure, which means that the explosion hazard increases. The flame propagation velocity in the roadway decreases linearly with the increase of initial pressure. When the initial pressure increases by 0.01 MPa, the flame propagation speed will decrease by 2.6%.