Nearly 80% of new cases of myopia arise between 9 and 13 years old when puberty development also progresses rapidly. However, little is known about the association between myopia and puberty. We aim to evaluate the association between myopia and menarche, the most important puberty indicator for girls, and to test whether menarche could modify the effects of myopia-related behaviors. The participants came from two consecutive national surveys conducted in 30 provinces in mainland China in 2010 and 2014. We included 102,883 girls (61% had experienced menarche) aged 10–15 years. Risk behaviors for myopia which included sleep duration, homework time, and outdoor activity were measured by self-administrated questionnaire. Myopia was defined according to a validated method, and its relationships with menarche status and behaviors were evaluated by robust Poisson regression models based on generalized estimated equation adjusting for cluster effect of school. We found that postmenarche girls were at 13% (95% confidence interval: 11%–16%) higher risk of myopia than premenarche girls, after adjusting for exact age, urban–rural location, survey year, and four behavioral covariates. Short sleep duration (<7 h/d), long homework time (>1 h/d) and low frequency of weekend outdoor activity tended to be stronger (with higher prevalence ratios associated with myopia) risk factors for myopia in postmenarche girls than in premenarche girls, and their interaction with menarche status was all statistically significant (P < 0.05). Overall, our study suggests that menarche onset may be associated with increased risk of myopia among school-aged girls and could also enhance girls’ sensitivity to myopia-related risk behaviors.

Novel ultrafine eutectic composites containing structural and spatial heterogeneities have been systematically developed in an Mg–Cu–Zn ternary system. Microstructural investigations of the ultrafine eutectic composites revealed that the bimodal eutectic structure consists of a mixture of cellular-type fine (α-Mg + MgZn2) and anomalous-type coarse (α-Mg + MgZn2 + MgCuZn) eutectic structures. An Mg72Cu5Zn23 alloy composed of the bimodal eutectic structure without micron-scale α-Mg dendrites presents a strong improvement of yield strength up to 455 MPa with a decent plastic strain of 5%. The rotation of the bimodal eutectic colony along the interfaces is considered to be an effective way to dissipate the stress localization thus enhancing the macroscopic plasticity.

In order to evaluate the environmental status within a mariculture pond, temporal variations of physico-chemical factors, protist community structure and interactions between biota and environmental conditions were investigated during a complete cycle in semi-enclosed shrimp-farming waters near Qingdao, north China. Results revealed that: (1) a total of 54 protist taxa with ten dominant species was present, comprising 4 chlorophyceans, 2 chrysophyceans, 5 cryptophyceans, 10 dinoflagellates, 3 euglenophyceans, 10 diatoms, 18 ciliates and 2 sarcodines; (2) a single peak of protist abundance occurred in October, mainly due to the chlorophyceans, diatoms and chrysophyceans, while the bimodal peaks of biomass in July and October were mainly due to the ciliates, dinoflagellates and diatoms; (3) the succession of protist communities significantly correlated with the changes of nutrients, salinity and temperature, especially phosphate, either alone or in combination with NO3; (4) species diversity and evenness indices were found to be relatively independent of physico-chemical factors, whereas species richness and the ratio of biomass to abundance were strongly correlated with water temperature and abundances of bacteria. It was concluded that planktonic protists are potentially useful bioindicators of water quality in a semi-enclosed mariculture system.

The effects of reactive ion etching damage on the electrical properties of Pt/SBT/Pt capacitors have been investigated. The plasma treated SBT/Pt layers showed a significant decrease in remanent polarization compared with that of the reference sample. The remanent polarization of the plasma treated layers varied with the gas ratios of the Cl2/Ar plasma. XPS analysis of the plasma treated SBT/Pt samples showed that the surface composition was significantly changed as the gas ratios were varied, which resulted in a polarization decrease in the plasma treated samples. Plasma treatment also caused a voltage shift of the hysteresis loops along the voltage axis. The magnitude of the voltage shift was increased for the chlorine-rich plasma. The results of surface analysis revealed that the voltage shift is caused by oxygen deficiency at the SBT surface. Based on our experimental results, reactive ion etching damage was explained in terms of physical and electrical effects of the plasma on the electrical properties of the ferroelectric Pt/SBT/Pt capacitors.