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To solve the problem of difficult focus, serious geometry distortion and large cross sidelobe in high-squint mode synthetic aperture radar (SAR) ground moving target imaging (GMTIm), a high-squint SAR GMTIm algorithm based on the ωk algorithm with spectrum rotation is proposed. Firstly, a moving target echo signal model with accurate slant-range is deduced in detail to obtain preliminary imaging result and extract the region of interest (ROD moving target data. Then, the phase compensation function is constructed and the minimum entropy algorithm is utilized to finish moving target parameter estimation. According to the estimated parameter, the phase of ROI data is compensated to get the focused moving target image. Furthermore, spectrum rotation eliminates geometry distortion, and the sparsity enhancement method decreases the moving target sidelobe. By doing so, focused, no geometry distortion and low sidelobe moving target image is obtained. Simulation results validate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Background: Non-alcoholic fatty liver disease (NAFLD) begins with hepatic lipid accumulation, and leptin has anti-steatosis properties. In this study, we investigated the effects of leptin on hepatic steatosis and inflammation through the vagal pathway independently of the inhibitory effect of food intake., Methods: Male Sprague-Dawley rats were matched for food intake after the high-fat diet (HFD)-induced obesity model and were injected intraperitoneally with leptin or leptin + lidocaine for 6 weeks. Control rats received equal volumes of saline. Adipose tissue mass, NAFLD activity scores (NAS), hepatic inflammatory factors, hepatic triglyceride content and hepatic lipid metabolism-related protein levels were evaluated., Results: Leptin ameliorated HFD-induced hepatic lipid accumulation, improved NAS, and decreased tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and monocyte chemotactic protein-1 (MCP-1) levels in the presence of matched intake. Lidocaine decreased the phosphorylation of signal transducer and activator of transcription 3 (p-STAT3) expression in the nucleus tractus solitarius (NTS) and abrogated the leptin-mediated improvement. Leptin increased hypothalamic phosphorylated Janus kinase 2 (p-JAK2) and p-STAT3 expression, as well as the expression of mitochondrial respiratory chain-related genes. Leptin also increased hepatic phosphorylated adenosine 5'-monophosphate-activated protein kinase (p-AMPK) expression and phosphorylation of its downstream target acetyl Co A carboxylase 1 (ACC1), reducing de novo lipogenesis., Conclusions: Our results suggest that leptin ameliorated hepatic lipid accumulation and inflammation by activating the JAK2-STAT3/AMPK pathway through the vagal pathway independently of the inhibitory effect of ingestion. Leptin has the potential to be a drug for early NAFLD treatment., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024. Published by Elsevier Inc.)