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Aiming at the weapon-target assignment (WTA) problem in cooperative air combat of manned vehicle and unmanned vehicle, this paper established a multi-objective optimization mathematical model, which included minimize the total survival probability of all targets and minimize the consumption of the air-to-air missiles, then put forward an improved multi-objective shuffled frog leaping algorithm (SFLA), which referred to as IMOSFLA, to solve the Pareto optimal solutions of this problem. The IMOSFLA made full use of the superiority of the shuffled frog leaping algorithm, high convergence speed and high convergence precision, to execute the global optimization firstly. Then the IMOSFLA used the adaptive grid algorithm to maintain and update the Pareto solutions. And then it introduced a kind of Tent chaotic mutation into the process of the global evolution of the frog species to avoid the IMOSFLA falling into the premature convergence. In addition, it defined an autonomous selection rule for optimum weapon-target allocation from the Pareto optimal solution set. Finally, the simulation experiments verified the feasibility and effectiveness of the proposed method. The experimental results show that the proposed method can solve the weapon-target assignment in cooperative air combat of manned vehicle and unmanned vehicle effectively. [ABSTRACT FROM AUTHOR]

A prototype of single-deck floating raft vibration isolator system with a fluid level controller was developed based on anti-resonance mechanism for attenuating low-frequency vibration. For verifying the effectiveness of anti-resonance mechanism, a series of experimental studies had been conducted on the characteristics of the force transmissibility against excitation frequency by tuning liquid levels. Furthermore a method of tuning liquid flowing gap was proposed and the experimental tests demonstrated the effectiveness of the method. Based on the experimental comparison between the tuning liquid level method and the tuning flowing gap method using anti-resonance frequency curves, a discussion of advantages and disadvantages of these two methods were provided according to the efficiency of tuning anti-resonance frequency, and a combination of the both schemes was suggested for the improvement of vibration attenuation in terms of lower force transmissibility and wider isolation bandwidth. [ABSTRACT FROM AUTHOR]

Objectives: Significant increase in tacrolimus exposure was observed during co-administration with voriconazole, and no population pharmacokinetic model exists for tacrolimus in renal transplant recipients receiving voriconazole. To achieve target tacrolimus concentrations, an optimal dosage regimen is required. This study aims to develop individualized dosing parameters through population pharmacokinetic analysis and simulate tacrolimus concentrations under different dosage regimens., Methods: We conducted a retrospective study of renal transplant recipients who were hospitalized at the Second Xiangya Hospital of Central South University between January 2016 and March 2021. Subsequently, pharmacokinetic analysis and Monte Carlo simulation were employed for further analysis., Results: Nineteen eligible patients receiving tacrolimus and voriconazole co-therapy were included in the study. We collected 167 blood samples and developed a one-compartment model with first-order absorption and elimination to describe the pharmacokinetic properties of tacrolimus. The final typical values for tacrolimus elimination rate constant (Ka), apparent volume of distribution (V/F), and apparent oral clearance (CL/F) were 8.39 h -1 , 2690 L, and 42.87 L/h, respectively. Key covariates in the final model included voriconazole concentration and serum creatinine. Patients with higher voriconazole concentration had lower tacrolimus CL/F and V/F. In addition, higher serum creatinine levels were associated with lower tacrolimus CL/F., Conclusion: Our findings suggest that clinicians can predict tacrolimus concentration and estimate optimal tacrolimus dosage based on voriconazole concentration and serum creatinine. The effect of voriconazole concentration on tacrolimus concentration was more significant than serum creatinine. These findings may inform clinical decision-making in the management of tacrolimus and voriconazole therapy in solid organ transplant recipients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Sun, Li, Liu, Zhang, Xie, Fang, Sandaradura, Peng and Yan.)

To understand the adaptation of water use strategy of plant community to habitat heterogeneity, we measured the δD and δ 18 O values of xylem water of shrubs and potential water sources (soil water in different layers or groundwater) of Ammopiptanthus mongolicus communities on sand dune and Gobi from April to September in 2021 in the Ulan Buh Desert. Employing the MixSIAR model, we examined the seasonal dynamics of water source of each shrub by quantifying the contribution of different potential water sources. The results showed that A. mongolicus and Artemisia xerophytica on sand dune mainly used soil water of 10-25 cm in April and May after heavy rain in early spring, whereas Artemisia ordosica mainly used soil water of 10-200 cm. During the drought event within summer from June to August, A. mongolicus increasingly used soil water of 100-200 cm and groundwater, but A. xerophytica and A. ordosica increased the usage of 50-200 cm soil water. After the moderate rain in September, A. mongolicus evenly used soil water in all layers and groundwater, whereas two Artemisia shrubs preferred soil water of 10-50 cm. On Gobi, A. mongolicus and Nitraria sphaerocarpa evenly used soil water in all layers in April and May, mainly used 50-150 cm soil water from June to August and used 10-50 cm soil water in September. Convolvulus tragacanthoides mainly used soil water of 10-50 cm (from April to May), 25-150 cm (from June to August), and 10-25 cm (in September), separately. There were seasonal differences in water use of three shrubs on sand dune and Gobi A. mongolicus communities. During drought, A. mongolicus on sand dune could use deep soil water and groundwater, and that on Gobi relied only on deep soil water, which was more sensitive to rainfall.