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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]

Background: Older patients with coronary artery disease (CAD) are particularly vulnerable to the efficacy and adverse drug reactions, and may therefore particularly benefit from personalized medication. Drug–gene interactions (DGIs) occur when an individual's genotype affects the pharmacokinetics and/or pharmacodynamics of a victim drug. Objectives: This study aimed to investigate the impact of cardiovascular-related DGIs on the clinical efficacy and safety outcomes in older patients with CAD. Methods: Hospitalized older patients (≥ 65 years old) with CAD were consecutively recruited from August 2018 to May 2022. Eligible patients were genotyped for the actionable pharmacogenetic variants of CYP2C9, CYP2C19, CYP2D6, CYP3A5, and SLCO1B1, which had clinical annotations or implementation guidelines for cardiovascular drugs. Allele frequencies and DGIs were determined in the cohort for the 5 actionable PGx genes and the prescribed cardiovascular drugs. All patients were followed up for at least 1 year. The influence of DGIs on the cardiovascular drug-related efficacy outcomes (all-cause mortality and/or major cardiovascular events, MACEs) and drug response phenotypes of "drug-stop" and "dose-decrease" were evaluated. Results: A total of 1,017 eligible older patients with CAD were included, among whom 63.2% were male, with an average age of 80.8 years old, and 87.6% were administrated with polypharmacy (≥ 5 medications). After genotyping, we found that 96.0% of the older patients with CAD patients had at least one allele of the 5 pharmacogenes associated with a therapeutic change, indicating a need for a therapeutic change in a mean of 1.32 drugs of the 19 cardiovascular-related drugs. We also identified that 79.5% of the patients had at least one DGI (range 0–6). The median follow-up interval was 39 months. Independent of age, negative association could be found between the number of DGIs and all-cause mortality (adjusted HR: 0.84, 95% CI: 0.73–0.96, P = 0.008), and MACEs (adjusted HR: 0.84, 95% CI: 0.72–0.98, P = 0.023), but positive association could be found between the number of DGIs and drug response phenotypes (adjusted OR: 1.24, 95% CI: 1.05–1.45, P = 0.011) in the elderly patients with CAD. Conclusions: The association between cardiovascular DGIs and the clinical outcomes emphasized the necessity for the integration of genetic and clinical data to enhance the optimization of cardiovascular polypharmacy in older patients with CAD. The causal relationship between DGIs and the clinical outcomes should be established in the large scale prospectively designed cohort study. [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 order to avoid the spectral signal instability and low detection accuracy originating from "transient plasma" produced by laser-induced breakdown (LIBS) technology, the LIBS system based on three-dimensional scaffold was developed to optimize the optical fiber detection position. The spectral signal quality of samples with different contents of KCl additives (0%–100%) at 20–280 °C was analyzed. The double spectral line internal standard model of Cd and Pb elements in sediment was established. The experimental results show that the signal-to-noise ratio of Cd and Al in the sediment with 15% KCl additive at 180 °C is 1.78 and 1.39 times higher than that without additive at room temperature. The R2 of the calibration model for Cd and Pb in sediment with the double enhancement method increased from 0.938 08 and 0.948 80 to 0.963 41 and 0.952 61. The spectral line integral area bispectral line internal scale model R2 is improved to 0.990 34 and 0.988 83. The results showed that the sample heating combined with KCl additive could improve the quality of the spectral signal and increase the detection sensitivity. [ABSTRACT FROM AUTHOR]

Background: This study aimed to evaluate the efficacy and safety of oral anticoagulants (OACs) in real-world elderly patients with comorbidities of stable coronary artery disease (SCAD) and atrial fibrillation (AF). Methods: Elderly patients (aged ≥ 65 years old) diagnosed with SCAD and AF were consecutively recruited and grouped into patients with or without oral anticoagulant (OAC) treatment. Follow-up was performed for 5 years. Major adverse cardiac events (MACEs) were defined as a composite of all-cause death, nonfatal myocardial infarction (MI), nonfatal stroke, and systemic embolism. Major bleeding outcomes were defined as events that were type ≥ 3 based on the Bleeding Academic Research Consortium (BARC) criteria. The net clinical outcomes were defined as the combination of MACEs and bleeding of BARC type ≥ 3. Results: A cohort of 832 eligible patients (78 ± 6.70 years) was included. Compared to the patients without OAC treatment (n = 531, 63.82%), the patients treated with OAC (n = 301, 36.18%) were much younger, had higher body mass index (BMI), and had lower prevalence of heart failure, chronic obstructive pulmonary disease (COPD), renal insufficiency, and previous myocardial infarction. During the follow-up of 5 years, compared to the patients without OAC treatment, patients with OAC had a significantly lower risk of MACEs (20.60% vs. 58.95%, adjusted HR: 0.21, 95% CI: 0.15–0.30, p < 0.001) but a higher risk of BARC ≥ 3 bleeding events (4.65% vs. 1.32%, adjusted HR: 4.71, 95% CI: 1.75–12.64, p = 0.002). In combination, a lower risk of net clinical outcomes could be observed in the patients with OACs (23.26% vs. 58.96%, adjusted HR: 0.27, 95% CI: 0.19–0.38, p < 0.001). Among the patients with OAC treatment, no significant difference was found for MACEs or BARC ≥ 3 bleeding events between the patients with or without comedications of oral antiplatelet agents. Conclusions: A net clinical benefit of efficacy and safety could be observed in OAC-treated elderly patients with SCAD and AF. This benefit is independent of the comedications of oral antiplatelet treatment. [ABSTRACT FROM AUTHOR]

A two circular-arc cam mechanism is a special kind of constant-breadth cam. At the junction point of each cam contour, a mutation of the curvature radius may be produced, which affects the motion performance of the mechanism, especially its jerk performance at high speed. Based on a proposed motion model, the follower movements of the constant-breadth two circular-arc cam mechanism with an inclined flat-faced follower are analyzed. Bezier Curve is proposed to fit the driving law of the cam mechanism, while variable speed law is adopted to drive the cam mechanism motion, thus reducing motion characteristic value (AV)max (i.e., the maximum value of the velocity multiplied by acceleration for the follower's motion law of the cam mechanism at the same motion time point) and the jerk of the follower. In this paper, the establishment of the optimization objective functions and constraint conditions, and the control node selections of the cam drive function are researched. The optimization results are obtained by using the primary objective method. The results of a test case calculation and simulation show that, the optimized drive function, according to the variable motor speed, can significantly reduce the value of (AV)max of the follower, while the jerks of the follower system are also reduced considerably. More precisely, the (AV)max value is reduced by 11.63% and the jerks are reduced on average by 15.35%, at the three jerk positions. The proposed methods provide a new approach to improving the kinematic performance of similar cam mechanisms. [ABSTRACT FROM AUTHOR]

Background: Despite strong antiplatelet therapy with ticagrelor, serious ischemic events still occur in patients with acute coronary syndrome (ACS). The predictability of platelet reactivity to the residual risk of ischemic events during ticagrelor treatment remains uncertain. Objectives: We aimed to investigate the predictability of the thromboelastography (TEG)-measured adenosine disphosphate (ADP)-induced platelet inhibition rate (ADP%) to the ischemic events in ticagrelor-treated patients with ACS. Methods: A cohort of ticagrelor-treated patients with ACS were consecutively recruited. ADP% was measured by TEG after 3 days of ticagrelor maintenance treatment. The primary ischemic event was defined as rehospitalization for unstable angina (UA) within 1 year, and the secondary ischemic event was a composite of the primary ischemic event plus all-cause death, nonfatal myocardial infarction (MI), stent thrombosis, stroke, and unplanned revascularization within 1 year. Results: A total of 751 eligible patients with ACS were included in the analysis, with 336 patients randomly assigned to the derivation group and 415 to the validation group. The overall rates of primary and secondary ischemic events were 14.51% (n = 109) and 16.91% (n = 127), respectively. Compared to the patients without ischemic events, those with ischemic events had a significantly lower ADP% both in the derivation group (for primary ischemic events: 66.05% vs. 92.80%, p < 0.001; for secondary ischemic events: 66.05% vs. 93.20%, p < 0.001) and in the validation group (for primary ischemic events: 66.40% vs. 89.20%, p < 0.001; for secondary ischemic events: 66.90% vs. 89.20%, p < 0.001). Receiver operating characteristic curve (ROC) analysis showed that an ADP% < 76% was the optimal cut-off value for predicting 1-year primary ischemic events, with an area under the curve (AUC) of 0.80 (95% CI: 0.72–0.86, p < 0.001) in the derivation group and 0.77 (95% CI: 0.69–0.85, p < 0.001) in the validation group. The multivariate Cox regression hazard analysis consistently identified an ADP% < 76% as an independent predictor of primary ischemic events in the derivation group (HR: 8.21, 95% CI: 4.82–13.99, p < 0.001) and in the validation group (HR: 6.34 95% CI: 3.32–12.11, p < 0.001). There was also a strong association between an ADP% < 76 and the occurrence of secondary ischemic events in the derivation group (HR: 7.33, 95% CI: 4.47–12.00, p < 0.001) and in the validation group (HR: 4.76, 95% CI: 2.73–8.32, p < 0.001). Conclusion: The ADP-induced platelet inhibition rate measured by TEG could predict ischemic events in ticagrelor-treated patients with ACS. [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]

In order to enhance the spectral characteristics of the laser-induced breakdown spectroscopy (LIBS), the spectral signals of soil samples with different concentrations of KCl and KI additives were analyzed. The optimal laser energy, the lens to sample distance (LTSD) and the delay time were determined. Under the optimum experimental conditions, the spectral intensity, signal-to-noise ratio (SNR) and plasma characteristics of Cd I 288.08 nm and Al I 394.40 nm in soil samples with 0%, 5%, 10%, 15%, 20%, 25% and 30% KCl and KI additives were analyzed. The experimental results show that the spectral intensities of Cd and Al in soil samples with 15% KCl are 1.33 times and 1.61 times of that of the original sample, while those with 15% KI are 1.84 times and 1.81 times. The SNR, plasma temperature and electron density are improved. This provides an experimental reference for improving the accuracy of LIBS in soil detection. [ABSTRACT FROM AUTHOR]

Background. This study aimed to analyse the role of the HAS-BLED score with the addition of genotype bins for bleeding risk prediction in warfarin-treated patients with atrial fibrillation (AF). Methods and Results. Consecutive patients with AF on initial warfarin treatment were recruited. For each patient, CYP2C9 ∗ 3 and VKORC1-1639 A/G genotyping was performed to create 3 genotype functional bins. The predictive values of the HAS-BLED score with or without the addition of genotype bins were compared. According to the carrier status of the genotype bins, the numbers of normal, sensitive, and highly sensitive responders among 526 patients were 64 (12.17%), 422 (80.23%), and 40 (7.60%), respectively. A highly sensitive response was independently associated with clinically relevant bleeding (HR: 3.85, 95% CI: 1.88–7.91, P = 0.001) and major bleeding (HR:3.75, 95% CI: 1.17–11.97, P = 0.03). With the addition of genotype bins, the performance of the HAS-BLED score for bleeding risk prediction was significantly improved (c-statistic from 0.60 to 0.64 for clinically relevant bleeding and from 0.64 to 0.70 for major bleeding, P < 0.01). Using the integrated discriminatory, net reclassification improvement, and decision curve analysis, the HAS-BLED score plus genotype bins could perform better in predicting any clinically relevant bleeding than the HAS-BLED score alone. Conclusions. Genotypes have an incremental predictive value when combined with the HAS-BLED score for the prediction of clinically relevant bleeding in warfarin-treated patients with AF. [ABSTRACT FROM AUTHOR]

The aim of this study is to investigate the relationship between the laser-induced optical breakdown energy threshold and the spectral signal changes with the spot radius. First of all, using the avalanche breakdown threshold theory calculates the threshold avalanche ionization rate ηc. Combining with the theory of light intensity distribution and the relationship between pulse energy and peak power, numerical calculations have obtained the law of change of spot radius and threshold laser energy. Secondly, the variation of the spectral signal-to-noise ratio (SNR) with the laser energy is measured according the experimental measurement, and the threshold laser energy required for optical breakdown at different spot radius is obtained. The theoretical threshold model of the relationship between the threshold laser energy and the quadratic function of the spot radius obtained by numerical calculation is verified, and it is revised, the results show that the relative error between the revised theoretical threshold model and the experimental threshold model is less than 5.3%. At last, the influence of the spot radius on the spectral signal and electron density is also analyzed, it is found that both the spectral intensity and the electron density have a maximum at the spot radius of 11 µm. The results show that it is necessary to find the best spot radius during the laser induced breakdown spectroscopy (LIBS) experiment. This provides a reliable theoretical basis and experimental reference for further study of the influence of spot radius on LIBS technology measurement. [ABSTRACT FROM AUTHOR]

Oceanic fronts involved by ocean currents led to strong gradients of temperature, density and salinity, which have significant effects on underwater sound propagation. This paper focuses on the impact of the oceanic front on three-dimensional underwater sound propagation. A joint experiment of ocean acoustic and physical oceanography at the western North Pacific fronts is introduced. The measurement data for sound waves passed through the oceanic front is processed. The results are analysed and compared with the numerical simulation. It was found that transmission loss presented some difference when the source was located in the front centre and sound waves propagated towards water mass on opposite sides of the front centre. And when the sound field is excited by the underwater explosion at a depth of 200 m, the effects of the horizontal refraction cannot be neglected. On the other hand, the transmission loss for sound pressure fell sharply and rose rapidly at the side of cold water masses. [ABSTRACT FROM AUTHOR]

Recent studies have illustrated that the Multichannel Analysis of Surface Waves (MASW) method is an effective geoacoustic parameter inversion tool. This particular tool employs the dispersion property of broadband Scholte-type surface wave signals, which propagate along the interface between the sea water and seafloor. It is of critical importance to establish the theoretical Scholte wave dispersion curve computation model. In this typical study, the stiffness matrix method is introduced to compute the phase speed of the Scholte wave in a layered ocean environment with an elastic bottom. By computing the phase velocity in environments with a typical complexly varying seabed, it is observed that the coupling phenomenon occurs among Scholte waves corresponding to the fundamental mode and the first higher-order mode for the model with a low shear-velocity layer. Afterwards, few differences are highlighted, which should be taken into consideration while applying the MASW method in the seabed. Finally, based on the ingeniously developed nonlinear Bayesian inversion theory, the seafloor shear wave velocity profile in the southern Yellow Sea of China is inverted by employing multi-order Scholte wave dispersion curves. These inversion results illustrate that the shear wave speed is below 700 m/s in the upper layers of bottom sediments. Due to the alternation of argillaceous layers and sandy layers in the experimental area, there are several low-shear-wave-velocity layers in the inversion profile. [ABSTRACT FROM AUTHOR]

A mesoscale eddy is detected and tracked in the western North Pacific region. Within the life cycle of the cyclonic eddies, the intensities of eddies make a difference. Satellite images indicate the oceanic eddy keeps westward-moving until it disappears. Oceanographic and acoustic characteristics of the eddy are studied. The acoustic energy distribution results from the different intensity of both modelled eddy and measured eddy are calculated. With sound propagation through the cyclonic eddy and anticyclonic eddy, the position of convergence zone moves away from and towards the acoustic source compared with the sound propagation through background hydrography. The coupling coefficient of different orders of normal modes changes significantly. The closer to the centre of the eddy, the stronger the coupling coefficient. [ABSTRACT FROM AUTHOR]

In order to analyze the frequency periodicity characteristics of acoustic field interference and realize acoustic source ranging (ASR), the normal mode model is used to analyze the interference characteristics of the broadband acoustic field under the condition of horizontally layered medium; the broadband received signal field when the broadband pulse signal passes through the acoustic field is also simulated. The variation of interference patterns with frequency is analyzed, and their spatial interference characteristics and mechanisms are analyzed. Based on the interference theory, the relation between the acoustic source range and the frequency periodicity of the broadband acoustic intensity interference is derived. Simulation and experimental results show that this relation can accurately estimate the far-field acoustic source range, and the estimation accuracy and real-time performance are greatly improved compared with previous methods. Besides, simulation shows that the method combined with multiple-receiver ranging obtains high-precision direction of arrival (DOA) estimation as well as ASR. The relation between acoustic source position and broadband acoustic field interference frequency periodicity can be used to improve far-field ASR and DOA estimation, which is of great value for oceanography, marine engineering, and marine military. In addition, this relation can also be extended to that between the modal interference frequency periodicity and other related parameters in other physical fields for parameter inversion. [ABSTRACT FROM AUTHOR]