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Objective(s): This study aimed to explore the therapeutic effect of fecal microbiota transplantation (FMT) on liver cirrhosis-induced rat models by studying changes in intestinal flora distribution and liver pathology. Materials and Methods: Cirrhosis was induced in adult male Sprague-Dawley rats using carbon tetrachloride; successful establishment of the cirrhosis model was verified using hematoxylin and eosin (HE) staining. Rats were divided into normal control, cirrhosis model+normal saline, and cirrhosis model+FMT groups. Fecal intestinal flora was analyzed using 16S rRNA high-throughput sequencing for each group. Alpha diversity, beta diversity, and functional prediction analyses were performed. Additionally, rat liver tissue was subjected to HE staining to compare the degree of fibrosis and liver damage between the groups.Results: FMT significantly improved the diversity, richness, and uniformity of the intestinal flora in rats with liver cirrhosis. Notably, post-FMT, the abundance of lactobacillaceae, bacilli, and bacteroidia increased, while the abundance of clostridia decreased. Moreover, hepatic fibrosis improved after FMT.Conclusion: The dysbiosis of intestinal flora in rats with liver cirrhosis improved after FMT. Thus, FMT can regulate intestinal flora, reduce liver inflammation, and improve hepatic fibrosis and cirrhosis.

Near space has attracted major countries’ attention due to the fact that it is a new cognitive space of Earth and acts as an important national security space. Near-space solar-powered unmanned aerial vehicles (UAVs) are becoming a focus of research in the aviation field. However, it is difficult for solar-powered UAVs to climb such high heights and achieving optimal cruising levels is challenging. A balloon-borne-based aircraft that rises with the help of a balloon avoids difficult climbing processes and initiates a new research direction in the near-space aviation domain. Simultaneously, the special mode of taking off poses a great challenge for the pull-up control of balloon-borne aircraft, especially for large wingspan aircraft. In this paper, we propose an adaptive launch control for the pull-up process of large-scale balloon-borne-based aircraft. First, the flight control of the pull-up process for a large-scale balloon-borne-based aircraft is analyzed. Then, a flight dynamic model considering elastic deformation is established. Finally, an adaptive aircraft pull-up control algorithm is proposed. We evaluate it by performing simulation experiments and comparing it with the latest control algorithm utilized in physical experiments. The experiment’s results demonstrate the effectiveness of the proposed algorithm with respect to overcoming challenges in controlling pull-up processes and its superiority compared to the latest control algorithm.

This paper explores a novel single tail tilt servomotor tri-rotor ducted vertical takeoff and landing unmanned aerial vehicle system (VTOL-UAV), and proposes a compound control method combining disturbance observer, model predictive control (MPC) and sliding mode nonlinear dynamic inversion (NDI), and realizes the robust tracking control of the VTOL-UAV trajectory under compound disturbance. Specifically, the inner loop adopts nonlinear dynamic inverse which improved by sliding mode to realize the pseudo linearization of the system. The outer loop adopts the model predictive control based on the E-SSPC (State Space Predictive Controller based on the Error model) method, on this basis, the sliding mode disturbance observer based on fast Super-twisting algorithm is introduced into the position loop to observe and compensate the disturbance in real time, which improves the robustness of the outer loop system. Numerical simulation experiments verify the effectiveness and robustness of the control method. Finally, the flight test of the VTOL-UAV is carried out.