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Cell senescence, glycolysis, and mitochondrial deficit jointly regulate the development of septic acute kidney injury (SAKI). This study aimed to explore the role of circular RNA HIPK3 (circHIPK3) in mitochondrial function in SAKI. The SAKI mouse model was established by Candida albicans infection, followed by Western blot assay, measurements of serum lactate, and adenosine triphosphate (ATP), 5,5′,6,6′‐tetrachloro‐1,1′,3,3′‐tetraethylbenzimi‐dazolylcarbocyanine iodide (JC‐1) staining and flow cytometry. Human renal tubular epithelial cells were treated with lipopolysaccharide to establish the SAKI cell model, followed by cell counting kit‐8 assay, tests of hexokinase activity, lactate production, oxygen consumption rate, extracellular acidification rate, ATP, and JC‐1 staining, and Western blot assay. The roles of mitochondrial pyruvate carrier 1 (MPC1) were validated by kidney function tests, hematoxylin and eosin staining, periodic acid‐Schiff staining, and SA‐β‐gal staining. circHIPK3 downregulation reduced glycolysis and mitochondrial dysfunction both in vivo and in vitro through the microRNA (miR)‐148b‐3p/DNMT1/3a/Klotho axis. Inhibition of miR‐148b‐3p or Klotho increased glycolysis and mitochondrial dysfunction. Knockdown of MPC1 increased lactate content and decreased ATP levels and MMP both in vivo and in vitro. Collectively, circHIPK3, in concert with the miR‐148b‐3p/DNMT1/3a/Klotho axis, increased glycolysis, and inhibited the negative regulation of lactate production by MPC1, and aggravated mitochondrial dysfunction and cell senescence in SAKI. [ABSTRACT FROM AUTHOR]

Dynamic positioning (DP) system is an advanced positioning system widely used in various special operation ships, and the design of control strategies to cope with different constraint conditions is the core technology of DP system research. In this study, a novel dual‐loop control law is proposed to effectively tackle the control challenges encountered by DP ships, particularly in the presence of input saturation and error constraints. Firstly, a saturation handling model is designed to avoid input saturation in the system. Subsequently, a dual‐loop DP control scheme is developed. The outer‐loop is responsible for the ship's position and heading control, while concurrently providing the command velocity signal essential for the inner‐loop. Specifically, a prescribed performance control strategy is designed in the outer‐loop to ensure precise control over positioning errors within predefined ranges and achieve desirable transient and steady‐state performance. The inner‐loop controls the ship's velocity signal, in which a feedback control law is designed based on Hamilton‐Jacobi‐Issacs (HJI) inequality to estimate generalized faults of the DP system. Finally, the proposed control law is validated through numerical simulations on a 76.2 m supply ship, demonstrating superior transient and steady‐state performance compared to existing methods. [ABSTRACT FROM AUTHOR]