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Injecting CO2 into coal seams to enhance coal bed methane (ECBM) recovery has been identified as a viable method for increasing methane extraction. This process also has significant potential for sequestering large volumes of CO2, thereby reducing the concentration of greenhouse gases in the atmosphere. However, for deep coal seams where formation pressure is relatively high, there is limited research on CO2 injection into systems with higher methane adsorption equilibrium pressure. Existing studies, mostly confined to the low-pressure stage, fail to effectively reveal the impact of factors such as temperature, high-pressure CO2 injection, and coal types on enhancing the recovery and sequestration of CO2-displaced methane. Thus, this study aims to investigate the influence of temperature, pressure, and coal types on ECBM recovery and CO2 sequestration in deep coal seams. A series of CO2 core flooding tests were conducted on various coal cores, with CO2 injection pressures ranging from 8 to 18 MPa. The CO2 and methane adsorption rates, as well as methane displacement efficiency, were calculated and recorded to facilitate result interpretation. Based on the results of these physical experiments, numerical simulation was conducted to study multi-component competitive adsorption, desorption, and seepage flow under high temperature and high pressure in a deep coal seam's horizontal well. Finally, the optimization of the total injection amount (0.7 PV) and injection pressure (approximately 15.0 MPa) was carried out for the plan of CO2 displacement of methane in a single well in the later stage. [ABSTRACT FROM AUTHOR]

Clinical annotations for the actionable pharmacogenetic variants affecting the efficacy of cardiovascular drugs have been collected, yet their impacts on elderly patients with coronary artery disease (CAD) undergoing polypharmacy remain uncertain. We consecutively enrolled 892 elderly patients (mean age 80.7 ± 5.2) with CAD and polypharmacy. All the included patients underwent genotyping for 13 variants in 10 pharmacogenes (CYP2C19, CYP2C9, CYP4F2, CYP2D6, VKORC1, SLCO1B1, APOE, ACE, ADRB1, and MTHFR), which have the clinical annotations for 12 drugs that are commonly prescribed for patients with CAD. We found that 80.3% of the elderly CAD patients had at least one drug–gene pair associated with a therapeutical drug change. After adjusting for covariates, the number of drug–gene pairs was independently associated with a decreased risk of both major cardiovascular events (MACEs) (adjusted hazard ratio [HR]: 0.803, 95% confidence interval [CI]: 0.683–0.945, p = 0.008) and all-cause mortality (adjusted HR: 0.848, 95% CI: 0.722–0.996, p = 0.045), but also with an increased risk of adverse drug reactions (ADRs) (adjusted HR: 1.170, 95% CI: 1.030–1.329, p = 0.016). The Kaplan–Meier survival curves showed that compared to patients without a drug–gene pair, a significantly lower risk of MACEs could be observed in patients with a drug–gene pair during a 4-year follow-up (HR: 0.556, 95% CI: 0.325–0.951, p = 0.013). In conclusion, the carrier status of the actionable drug–gene pair is predictive for the clinical outcomes in elderly patients with CAD and polypharmacy. Implementing early or preemptive pharmacogenetic panel-guided polypharmacy holds the potential to enhance clinical outcomes for these patients. [ABSTRACT FROM AUTHOR]

In an effort to alleviate the issue of knee joint fatigue and injury during lower limb ambulation, a novel passive assisted exoskeleton robot with human–machine interaction is investigated to assist the movement of the human knee joint. The design of the exoskeleton configuration takes into consideration the physiological structure and gait function of the knee joint, ensuring that it satisfies the requirements for motion, force, and gait function of the knee joint. To explore the interaction between the wearer and the exoskeleton, a human–machine kinematic model after wearing exoskeleton is established, which is instrumental in analyzing the integration motion of the wearer and exoskeleton. In addition, the dynamic and static models of the knee joint after wearing the exoskeleton are established, utilizing the Newton–Euler method and force polygon method, respectively, to evaluate the effectiveness of the exoskeleton. Moreover, the size parameters and spring stiffness of the exoskeleton are optimized, using both human body kinematic model and mechanic model. Furthermore, the effectiveness of the exoskeleton in proving assistance is evaluated through human body simulation, using OpenSim. The results indicate that the exoskeleton significantly reduces the knee joint torque by 48.42%. [ABSTRACT FROM AUTHOR]

Introducing nanomaterials in gas sensor applications has conspicuously improved the detection performance due to the unique nanostructures. Transition-metal dichalcogenides (TMDs) recently aroused widespread interest because of their ultrathin and layered two-dimensional nanosheet structures. The graphene-like MoS2 has good electrical, chemical, mechanical, and optical properties, making it of great interest for developing gas sensors and an exceptionally promising building block for designing novel semiconducting nanomaterials. The content of this mini-review aspires to summarize the current progress on mono/few-layered MoS2-based gas sensors and the influence of different components. Herein, we described the current progress on MoS2-based gas sensors, which encompasses the preparation and application of MoS2, and the potential improvement directions for future possibilities of expanding its applications. [ABSTRACT FROM AUTHOR]

In this paper, a cam-linkage mechanism with a swing follower with variable pivot has been studied. In this mechanism, the pivot of the swing follower is installed on a slider with an adjustable track direction, the follower performs a complex planar motion, and the motion range of the output angle can be adjusted according to the output requirements. In order to synthesize this mechanism, firstly, the relevant model is established and the basic structural parameters are optimized by considering the assembly conditions and the pressure angle under the limit position of the movement track of the follower mounting slider. Subsequently, the inverse method and the envelope theory are employed to derive the cam contour coordinates. Finally, the corresponding follower motion law is selected, the corresponding cam contour coordinates are calculated, and the entire cam contour curve is obtained using spline interpolation. An automatic design system for cam contours is developed. The processes are carried out through design examples and verified through motion simulations and prototype experiment. The present work can enrich the design theory of cam-linkage mechanisms. [ABSTRACT FROM AUTHOR]