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Coherently combining distributed apertures adjusts the transmitted/received signals of multiple distributed small apertures, allowing coordinated distributed systems to obtain high power aperture products at much lower cost than large aperture. This is a promising and viable technology as an alternative to using large apertures. This study describes the concept and principles of coherently combining distributed apertures. Depending on whether external signal inputs at the combination destination are necessary, the implementation architecture of coherent combination is classified into two categories: closed- and open-loop. The development of coherently combining distributed apertures and their application in fields such as missile defense, deep space telemetry control, radar detection over ultralong range, and radio astronomy are then comprehensively presented. Furthermore, key techniques for aligning the time and phase of the transmitted/received signals for each aperture are elaborated, which are also necessary for coherently combining distributed apertures, including high-precision distributed time-frequency transfer and synchronization, and coherently combining parameters estimation, measurement and calibration, and prediction. Finally, summary is presented, and the scope of future works in this field is explored.

Carbon dots (CDs) have been applied to solid lighting because of their excellent fluorescent properties, good chemical stability, easy functionalization, and other advantages. However, the low thermal stability of most CDs limits the wide application of CDs as phosphors in laser illumination field. Aiming at CDs with high thermal stability and low cost, Y-CDs with fluorescent quantum yield of 49% were prepared by one-step hydrothermal method using citric acid and 2，7-dihydroxynaphthalene as raw materials and adjusting the concentration of reactants. The YG-CDs after annealing only lost 10% of weight at 250 ℃, while their thermal stability was greatly improved. The fluorescent films with good transmittance, fluorescent property, and thermal stability were obtained by combining the annealed YG-CDs with three film-forming agents (polymethyl methacrylate, polyvinyl alcohol, and silane coupling agent). This research provides a theoretical and practical basis for the application of CDs-based fluorescent films for laser illumination.

Objective To investigate the effect of high keratin 23 （KRT23） expression promoting cell proliferation on liver cancer. Methods The expression of KRT23 in liver cancer was analyzed by bioinformatics. After overexpression and inhibition of KRT23， the effect of KRT23 on the proliferation of liver cancer cells was analyzed by MTT and clone formation assay. The regulatory relationship between KRT23 and AKT signaling pathway was analyzed by software prediction， qPCRand Western blot. Results The expression level of KRT23 in liver cancer was significantly higher than that in normal control tissues. MTT and clone formation assay showed that overexpression of KRT23 promoted cell proliferation， while downregulation of KRT23 inhibited cell proliferation. GSEA analysis， qPCR and Western blot showed that KRT23 could activate the AKT signaling pathway and promote cell proliferation. Meanwhile， inhibition of AKT signaling pathway in overexpressing KRT23 cells significantly reduced cell proliferation. Conclusions KRT23 affects the proliferation of liver cancer cells by regulating the AKT signaling pathway. These results suggest that KRT23 exerts significant effects upon the malignant procession of liver cancer and may play an important role in the occurrence and development of liver cancer.