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This paper studies on the refueling boom aerodynamic characteristics and proposes an elastic suppression method for the refueling boom with the property of large length-diameter ratio. In order to obtain the accurate frequency response, modal analysis for the refueling boom is conducted based on ANSYS MODAL. Then the dynamics and kinematic equations of the elastic refueling boom are deduced, which contain the frequency parameter. To complete the equations, the aerodynamic performance is solved in ANSYS FLUENT. In addition, based on the mixed H2 / H∞ theory, an optimal PID controller is proposed to suppress the elastic deformation. Furthermore, the parameters of the PID controller are optimized with the differential evolution algorithm. Simulation shows that the different elastic mode has different effect on the control of the refueling boom. The elastic deformation is suppressed obviously for each mode.

The use of machine vision to track the receiver aircraft’s receptacle is one of the key steps in automated aerial refueling. Traditional Meanshift tracking algorithm’s kernel bandwidth is fixed, when the target size changes, it will produce with the bias even with the loss of the situation. Aiming at this problem, this paper proposes a kernel bandwidth adaptive algorithm based on corner matching. First, use backward tracking method to amend the core window center. Then according to the Harris algorithm to detect the corner, use small-scale approach for the two points between frames to match and regression analysis, namely determine the update parameters of nuclear window width. Experiments show that the algorithm can track the target accurately when the size of tracking target change, and the kernel window width can be better suited to the target size.

Transforming growth factor β type 1 receptor (TGFβR1), a crucial serine-threonine kinase, is central to the TGFβ/Smad signaling pathway, governing cellular processes like growth, differentiation, apoptosis, and immune response. This pathway is closely linked to the epithelial–mesenchymal transition (EMT) process, which plays an important role in the metastasis of hepatocellular carcinoma (HCC). To date, only limited inhibitors targeting TGFβR1 have entered clinical trials, yet they encounter challenges, notably high toxicity, in clinical applications. Herein, an efficient virtual screening pipeline was developed. Eighty compounds were screened from a pool of over 17 million molecules based on docking scores and binding free energy. Four compounds were manually selected with the assistance of enhanced sampling method BPMD (binding pose metadynamics). The binding stability of these four compounds complexed with TGFβR1 was subsequently studied through long-timescale conventional molecular dynamics simulations. The three most promising compounds were subjected to in vitro bioactivity assays. Cpd272 demonstrated moderate inhibitory activity against TGFβR1, with an IC50 value of 1.57 ± 0.33 μM. Moreover, it exhibited cytotoxic effects on human hepatocellular carcinoma cell line Bel-7402. By shedding light on the binding mode of the receptor–ligand complexes, Cpd272 was identified as a hit compound featuring a novel urea-based scaffold capable of effectively inhibiting TGFβR1. [ABSTRACT FROM AUTHOR]

Simple Summary: Defatting can be performed mechanically by cutting the frozen insect larvae and then pressing them to enable the leakage of intracellular fat, or chemically using petroleum ether extraction of the insect meal. This study aimed to investigate the effects of different defatting methods of black soldier fly (Hermetia illucens) larvae meal (BSFM) on the metabolic energy and nutrient digestibility in laying hens. The results show that both defatting methods of BSFM had no adverse effects on the metabolic energy and nutrient digestibility in young laying hens, but pressed black soldier fly meal (BSFMp) demonstrated better effects on the digestibility of metabolic energy and nutrients in the feed for young laying hens. This study aimed to investigate the effects of different defatting methods of black soldier fly (Hermetia illucens) larvae meal (BSFM) on the metabolic energy and nutrient digestibility in laying hens. Sixty young laying hens (Hy-Line W-36) aged 63 days were randomly divided into two groups (G1 and G2), each with five replicates of six hens housed in individual cages. Group G1 was fed 25% pressed black soldier fly meal (BSFMp) and 75% basal diet, and Group G2 was fed 25% extracted black soldier fly meal (BSFMe) and a 75% basal diet. Both diets included 5 g/kg chromium oxide as an external marker. A 7-day preliminary trial was followed by a 4-day experimental period. The results indicate that pressing and extracting significantly affected the digestibility of crude fat and total energy in BSFM, with BSFMp showing significantly higher crude fat digestibility than BSFMe. Similarly, total energy digestibility was also significantly higher in BSFMp. However, there were no significant differences in dry matter, organic matter, and crude protein digestibility between the two processing methods. The apparent metabolic energy values of BSFMp and BSFMe were 16.34 and 12.41 MJ/kg, respectively, showing a significant difference. The nitrogen-corrected metabolic energy values were 15.89 MJ/kg in BSFMp and 11.93 MJ/kg in BSFMe, indicating a highly significant difference. The digestibility of arginine and leucine in BSFMp was significantly higher than in BSFMe, while differences in lysine, cystine, threonine, tryptophan, and isoleucine were not significant. In conclusion, both defatting methods of BSFM had no adverse effects on the metabolic energy and nutrient digestibility in young laying hens, but BSFMp demonstrated better effects on the digestibility of metabolic energy and nutrients in the feed for young laying hens. [ABSTRACT FROM AUTHOR]

A fault on the DC side of a flexible HVDC system, along with the rise in short-circuit current, develops rapidly. With the gradual expansion of flexible HVDC technology to large capacities and long-distance transmission and offshore transmission scenarios, the problem of short-circuit current calculation considering the characteristics of line distribution parameters needs urgent attention. Therefore, in order to solve the problem of the inaccurate calculation of the short-circuit current on the DC side, the lumped parameter model is used in a flexible DC system for long-distance transmission. This study analyzes the transmission line structure on the basis of the general model of the MMC short-circuit current calculation on the DC side and establishes a mathematical model of a long-distance transmission line considering the characteristics of distributed parameters. Two impedance equivalent models for different length lines are proposed to facilitate the analytical calculation of the short-circuit current. A short-circuit current calculation method for a flexible HVDC system with long-distance transmission lines is proposed. Additionally, the correctness of the proposed method is verified through the comparison of the simulation values and calculation values. The results show that the error of the lumped parameter calculation is about 10%, and the error of the distributed parameter calculation is less than 2%. [ABSTRACT FROM AUTHOR]