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Combining Ceramic and metal phases by explosion treatment is difficult on account of the low toughness and plasticity of the ceramic phases. To solve the problem, fine Yttria-Stabilized Zirconia (YSZ) powders were selected as an example in this work. It can be observed that part of the YSZ powders would agglomerate to spherical large particles spontaneously and YSZ layer can combine with steel substrates strongly after explosion treatment as expected. It can be explained by finite element modeling that YSZ powders were more likely to combine the steel substrate when large and small particles coexisted. Moreover, the interface between YSZ and steel substrates was investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). It was found that numerous sharp corners were generated at the interface during explosion process which possessed high resilience, and they improved the bearing capacity of the interface. In microcosm, semi-coherent boundaries and amorphous phases were detected at the interface which led to the strong metallurgical bonding between the two phases. In general, this work offers a feasible method to combine ceramic and metal substrate efficiently in a simple way. [ABSTRACT FROM AUTHOR]

The cathepsin E-A-like, also known as ‘similar to nothepsin’, is a new member of the aspartic protease family, which may take part in processing of egg yolk macromolecules, due to it was identified in the chicken egg-yolk. Previously, studies have suggested that the expression of cathepsin E-A-like increased gradually during sexual maturation of pullets, but the exact regulation mechanism is poorly understood. In this study, to gain insight into the function and regulation mechanism of the gene in egg-laying hen, we cloned the cathepsin E-A-like gene and evaluated its evolutionary origin by using both phylogenetic and syntenic methods. The mode of the gene expression regulation was analysed through stimulating juvenile hens with 17β-estradiol and chicken embryo hepatocytes with 17β-estradiol combined with oestrogen receptor antagonists including MPP, ICI 182,780 and tamoxifen. Our results showed that cathepsin E-A-like was an orthologoues gene with nothepsin, which is present in birds but not in mammals. The expression of cathepsin E-A-like significantly increased in a dose-dependent manner after the juvenile hens were treated with 17β-estradiol (P<0.05). Compared with the 17β-estradiol treatment group, the expression of cathepsin E-A-like was not significantly changed when the hepatocytes were treated with 17β-estradiol combined with MPP (P<0.05). In contrast, compared with the 17β-estradiol combined with MPP treatment group, the expression of cathepsin E-A-like was significantly downregulated when the hepatocytes were treated with 17β-estradiol combined with tamoxifen or ICI 182,780 (P<0.05). These results demonstrated that cathepsin E-A-like shared the same evolutionary origin with nothepsin. The expression of cathepsin E-A-like was regulated by oestrogen, and the regulative effect was predominantly mediated through ER-β in liver of chicken. [ABSTRACT FROM AUTHOR]