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Coalbed methane (CBM) content is a crucial parameter for CBM exploitation and disaster prevention, with accurate gas loss calculation being essential for improving measurement precision. To investigate the physical response to gas loss and quantify the impact and interrelation of various factors, this study developed a comprehensive model incorporating the effects of gas diffusion, temperature, and pressure effects on porosity and coal deformation. By utilizing the OpenFOAM platform and C++ for numerical solution development and establishing an experimental system for gas loss measurement, the model's reliability was confirmed. The new model demonstrates an 8.56% average error, representing a significant improvement over traditional methods, with error reductions of 26.59% and 18.31% compared to the square root of time and power function methods, respectively. The hierarchy of gas loss is determined to be gas flow > gas-coal deformation coupling > gas-temperature coupling > gas-coal deformation-temperature coupling. Average diffusion contributions are identified as 41.43% from surface diffusion, 30.71% from Knudsen diffusion, and 27.86% from viscous flow. The factors affecting gas loss, in decreasing order of impact, are adsorption equilibrium pressure, temperature, porosity, moisture, and adsorption constants. These findings provide theoretical support for enhancing gas content measurement accuracy and techniques, significantly benefiting CBM extraction and mine safety. [ABSTRACT FROM AUTHOR]

The dynamic evolution mechanism of gas explosion pressure drop is the basis of theoretical and field application research of point type gas fracturing coal seam permeability increasing technology. The experimental results show that the pressure time history trend after the gas explosion is triggered generally presents a rapid rise and a nonlinear decline; due to the coupling effect of the non-uniform gas ejection and the noise of the piezoelectric sensor itself, the local irregular and unsteady pressure fluctuation occurs. It is found that the gas explosion port has the fastest rate of pressure rise, and the time and distance between the gas explosion port and the gas explosion port increase slowly after a rapid increase, which shows a power-law of pressure rise as a whole; the gas explosion port is the peak pressure area, and the gas explosion pressure decreases with the increase of distance from the gas explosion port, which shows a quadratic parabola of unsteady pressure drop as a whole.

Based on the principle and method of ergonomics， the structure and motion characteristics of the lumbar joint of human body are analyzed. According to the above features and combined a discontinuously movable mechanism in the limb， an office chair for health is a hybrid mechanism that has 3R motion with bifurcated motion and can realize the human body waist joint movement is proposed. Then the operation mode is analyzed. The results show that， the hybrid mechanism has instantaneously three degrees of freedom at the constraint singular configuration. At this time， the method of redundant drive can be used to change the three-rotation mode into the two-rotation mode. Finally， the forward solution analysis equations of the hybrid mechanism in different operation modes are derived. The results show that the mechanism is completely decoupled.

As for the problem that the efficiency of picking of naval orange is low，a kind of picking actuator with surrounding and swallowing is designed，whose structure of implement is mainly consisted of multiplex slider rocker mechanism.Firstly，structure sketch of that installation is completed by referring to the operating principle of actuator designed，and the analysis of kinematics and dynamics is carried out.Then，the mathematical model of objective function is established based on the least consuming time，the optimized size of related structure are got by utilizing the Matlab software.Finally，based on the obtained dimension，the 3D model of end-effector is achieved，kinematics simulation is carried out by applying Adams software，the rationality and feasibility of design of actuator for naval orange harvesting is verified，and the theoretical support for the practical picking experiment is provided.

The stress changes, transient charges and microseismic signals of briquette samples during uniaxial compression failure were monitored and analyzed by using the self-made experimental system for measuring transient charges and microseismic signals on the surface of briquette.The experimental results show that the surface of briquette sample will produce transient charge during uniaxial compression failure, and the charge signal changes instantaneously and monopulse, and lasts for a long time, about 5~12 s.However, the microseismic signals show obvious paroxysmal occurrence with a short duration of about 0.2~0.4 s.Surface transient charges and microseismic signals are strongly correlated with stress changes, and their overall trend of change has a high synchronization in time scale.The time difference between the peak values of the two signals is about 0.08~0.5 s.There is a critical point of energy release in the process of sample failure, which corresponds to the time of sudden stress change.By using the time scale consistency of surface transient charge and microseismic signal and the characteristics of the critical point of energy release, the process of coal and rock mass failure can be predicted and analyzed more accurately.

Glucagon‐like peptide‐1 (GLP‐1) can improve cardiac function and cardiovascular outcomes in diabetic cardiomyopathy; however, the beneficial effect of GLP‐1 on human diabetic cardiomyocytes (DCMs) and its mechanism have not been fully elucidated. Here, the DCMs model by human‐induced pluripotent stem cells‐derived cardiomyocytes is developed. Two subtypes of GLP‐1, GLP‐17–36 and GLP‐19‐36, are evaluated for their efficacy on the DCMs model. Diabetogenic condition is sufficient to induce most characteristics of diabetic cardiomyopathy in vitro, such as cardiac hypertrophy, lipid accumulation, impaired calcium transients, and abnormal electrophysiological properties. GLP‐17−36 and GLP‐19–36 can restore cardiomyocyte hypertrophic phenotype, impaired calcium transient frequency, abnormal action potential amplitude, depolarization, and repolarization velocity. Interestingly, RNA‐seq reveals different pathways altered by GLP‐17–36 and GLP‐19–36, respectively. Differentially expressed gene analysis reveals that possible targets of GLP‐17–36 involve the regulation of mitotic nuclear division and extracellular matrix–receptor interaction, while possible targets of GLP‐19–36 involve kinetochore assembly, and the complement and coagulation cascades. This study demonstrates the therapeutic effects of GLP‐1 on human DCMs and provides a novel platform to unveil the cellular mechanisms of diabetic cardiomyopathy, shedding light on discovering better targets for novel therapeutic interventions. [ABSTRACT FROM AUTHOR]