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Fucoidan (FU) is a natural sulfated polysaccharide with certain biological activity and has been shown to be an excellent nano-delivery material. In this study, ferulic acid (FA)-loaded FU nanoparticles (FA/FU NPs) were prepared and their nephroprotective mechanism was investigated. With a particle size of 158.6 ± 4.5 nm, FA/FU NPs increased the antioxidant activity of FA in vitro, possibly related to the increased dispersity of FA. In vitro results demonstrated that FA/FU NPs significantly protected human renal proximal tubule (HK-2) cells from cisplatin-induced damage, possibly by suppressing cisplatin-induced DNA damage and activating the cGAS-STING pathway. Furthermore, in vivo experiments confirmed that FA/FU NPs protected mice from cisplatin-induced acute kidney injury (AKI). Mechanistic studies confirmed that FA/FU NPs exerted nephroprotective effects by reducing MDA activity and increasing GSH and SOD activity. Our results demonstrated the potential of FU for delivering poorly soluble drug FA and protecting against cisplatin-induced AKI.

Silk fibroin (SF) is a natural polymeric biomaterial widely used in the preparation of drug delivery systems. Herein, silk fibroin peptide (SFP) was self-assembled into nanofibers, encapsulated a poorly water-soluble drug baicalein (SFP/BA NFs), and then used to protect against cisplatin-induced acute kidney injury (AKI). Specifically, the SFP/BA NFs significantly enhanced the aqueous dispersity, storage stability, and in vitro antioxidant activity of BA. SFP/BA NFs increased the drug uptake and localization to mitochondria. In vitro results demonstrated that SFP/BA NFs can relieve the cisplatin-induced HK-2 cell damage, and inhibit the cisplatin-induced accumulation of reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) disruption. Mechanism studies demonstrated that SFP/BA NFs may exert nephroprotective effects by inhibiting both the cisplatin-induced DNA damage and the cGAS/STING pathway activation. In vivo results showed that cisplatin treatment resulted in decreased body weight, increased serum creatinine (SCr), and increased blood urea nitrogen (BUN) levels, while SFP/BA NFs reversed the above symptoms. Furthermore, SFP/BA NFs reversed the cisplatin-induced abnormal changes of antioxidant enzymes (e.g., SOD and GSH), and inhibited the cisplatin-induced DNA damage as well as the activation of cGAS/TING. Above all, our results revealed the potential of SFP/BA NFs to protect against cisplatin-induced AKI.

For the safety and reliability concerns for the Chinese Fusion Engineering Test Reactor (CFETR) and future tokamak devices, a large-scale high-intensity static magnetic field immunity test platform is planned in Chinese Academy of Sciences, Institute of Plasma Physics (ASIPP). This paper presents the preliminary design of the coil system which is used to generate a high-strength uniform magnetic field in a large test zone. At first, a magnetic field homogeneity analysis is performed to determine the structural parameters of the test coil which satisfies the test requirement at a low power loss. The electrical parameters of the coil are then determined based on the structural parameters. In addition, the design of cooling system for the test coil is performed based on theoretical analysis, and then verified by a CFD analysis. The square-shaped designed coil system is able to continuously generate a uniform magnetic field with a field strength over 700 m T in a test zone with a side-length of 2.1 m, which enables the immunity test for large devices at a nominal test level up to 500 m T. It is of great value to ensure the reliable operation of electrical and electronic equipment in CFETR and future devices.

Current sharing among multi-parallel thyristors is a key task in the design of high-current converters. However, conventional current sharing methods seldom consider the stray inductance which acts a significant role in the current sharing. This paper mainly focuses on stray inductance, and builds a current sharing equation based on Partial Element Equivalent Circuit (PEEC) method for the current sharing analysis and design of high-current converters. The deduction of the equation is presented. As an example, the application of the proposed method in the design of the International Thermonuclear Experimental Reactor (ITER) Poloidal Field Converter Unit (PFCU) is briefly presented. The current sharing coefficient is over 0.8, which is greatly improved and beyond the required value. The method proposed in this paper can be used for the fast design of the physical layout of a converter, and further improve its current sharing along with conventional design methods.

The magnetic field environment around tokamak devices is very strong, which affects the working characteristics of electrical and electronic devices. For the study of magnetic field interference problems and the qualification test of sensitive devices, an immunity test platform against both D.C. and power-frequency magnetic fields is designed in this paper, including the analysis and design of magnetic field generating coil and the power supply. The rated D.C. and power-frequency magnetic fields of the test coil are 200 mT and 50 mT, respectively, and the field inhomogeneity is 1.1. The electromagnetic design and the thermal design of the test coil are presented. The power supply adopts the three-stage series structure of rectifier, D.C. bus and H-bridge to enable the output of both D.C. and power-frequency currents. As the test requires a wide output current range with a high accuracy, an improved topology is proposed to ensure the stability and accuracy at all test levels. The operation principle and control strategy of the topology are analyzed and presented. The simulation results show that the topology and control strategy meet the design requirements.