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Abstract Benefitted from progress on the large-diameter Ga 2 O 3 wafers and Ga 2 O 3 processing techniques, the Ga 2 O 3 power device technology has witnessed fast advances toward power electronics applications. Recently, reports on large-area (ampere-class) Ga 2 O 3 power devices have emerged globally, and the scope of these works have gone well beyond the bare-die device demonstration into the device packaging, circuit testing, and ruggedness evaluation. These results have placed Ga 2 O 3 in a unique position as the only ultra-wide bandgap semiconductor reaching these indispensable milestones for power device development. This paper presents a timely review on the state-of-the-art of the ampere-class Ga 2 O 3 power devices (current up to >100 A and voltage up to >2000 V), including their static electrical performance, switching characteristics, packaging and thermal management, and the overcurrent/overvoltage ruggedness and reliability. Exciting research opportunities and critical technological gaps are also discussed. 

Bio-inspired pinecone-like bioactive glasses consisting of ordered thin-layers separated by consistent cavities were synthesized using a sol–gel process. The short diameter of the as-produced particles was as short as 161 nm, and the surface area was as high as 280 m 2 g −1 . The pore volume, ranging from ∼0.74 cm 3 g −1 to ∼0.67 cm 3 g −1 , could be modulated by the aqueous ammonia concentration. The surface was further tailored for positive charges by amino grafting. The as-produced nanoparticles could successfully enter cells via endocytosis. The microRNA delivery of the bioactive glass particles was further investigated by fluorescence microscopy and flow cytometry, indicating a loading efficiency and transfection efficiency greater than 90%. The potential of such particles as drug carriers was also studied. CCK8, live–dead cell staining and PI/annexinV double staining analyses confirmed that the bioactive glass particles loaded with antitumour doxorubicin (DOX) significantly accelerated the apoptosis of tumour cells. These bio-inspired bioactive glasses are promising as novel vectors for drug and microRNA delivery with high efficiency.