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The excellent properties of metallic glass (MG) films make them perfect candidates for the use in miniature systems and tools. However, their high coefficients of friction (COFs) and poor wear resistance considerably limit their long-term performance in nanoscale contact. We report the fabrication of a MG/graphene multilayer by the repeated deposition of Cu50Zr50 MG with alternating layers of graphene. The microstructure of the multilayer was characterized by the transmission electron microscopy (TEM). Its mechanical and nanotribological properties were studied by nanoindentation and nanoscratch tests, respectively. A molecular dynamics (MD) simulation revealed that the addition of graphene endowed the MG with superelastic recovery, which reduced friction during nanoscratching. In comparison with the monolithic MG film, the multilayer exhibited improved wear resistance and a low COF in repeated nanowear tests owing to the enhanced mechanical properties and lubricating effect caused by the graphene layer. This work is expected to motivate the design of other novel MG films with excellent nanowear properties for engineering applications. [ABSTRACT FROM AUTHOR]

The hypothalamus–pituitary–ovary axis is the most important system for regulating female reproductive endocrine function. Its dysfunction would lead to the abnormal secretion of gonadotropin-releasing hormone, follicle-stimulating hormone, or luteinizing hormone, and eventually result in the occurrence of reproductive disease, such as congenital hypogonadotropic hypogonadism, polycystic ovary syndrome, and premature ovarian failure. Recently, an anti-aging gene, Klotho, has gained broad attention in female reproductive diseases. Reports have shown that Klotho is closely correlated to the hypothalamus–pituitary–ovary axis and plays a key role in the development and progression of reproductive diseases. With this issue, we generally review the physiological and pathological role of Klotho in the hypothalamus–pituitary–ovary axis. We also review the underlying mechanisms of Klotho in promoting and preventing female reproductive diseases, which involve the dysfunction of the fibroblast growth factor–Klotho endocrine system, the abnormal signaling regulation of Wnt-β-catenin and insulin-like growth factor-1, the accumulation of oxidative stress, and the inhibition of autophagy, eventually affecting the genesis, development, ovulation, or atresia of follicles. The present review would provide new insights and potential therapeutic target strategies for clinical strategies. [ABSTRACT FROM AUTHOR]

Although previous studies have shown a close relationship between gaming disorder and depressive symptoms, few have measured normal videogame use, symptoms of gaming disorder, and depressive symptoms concurrently. The longitudinal dynamics between these variables remain unclear. This study used two demographic cohorts to examine the longitudinal relationship between gaming and depressive symptoms: children (n = 1513, 46.9% girls, Mage ± SD = 9.63 ± 0.58 years) and adolescents (n = 1757, 48.5% girls, Mage ± SD = 12.55 ± 0.70 years). Random intercept cross-lagged panel models (RI-CLPMs) were employed to distinguish between within- and between-person levels of gaming and depressive symptoms. The RI-CLPM results showed a stable link between symptoms of gaming disorder and depression at the between-person level for both children and adolescents. At the within-person level, among children, depressive symptoms positively predicted subsequent gaming disorder symptoms, but gaming disorder symptoms were not a significant predictor of depressive symptoms at this level. Among adolescents, there was no significant cross-lagged effect between symptoms of gaming disorder and depression at the within-person level. Additionally, there was no significant cross-lagged effect between normal videogame use and depressive symptoms in either cohort. These results highlight the different effects of normal videogame use and gaming disorder symptoms associated with depressive symptoms. The different effects on children and adolescents underscore the importance of considering the different developmental stages in the study of gaming and mental health outcomes. [ABSTRACT FROM AUTHOR]