Understanding fundamental crystal nucleation and growth mechanisms is critical for producing materials with controlled size and morphological features and uncovering structure–function relationships in these semiconducting oxides. Under hydro-solvothermal conditions, uniform branched and spherulitic TiO2 rutile nanostructures were formed via (101) twins. On the basis of detailed, high-resolution scanning electron microscopy and transmission electron microscopy analyses, we propose a mechanism of branched growth and the (101) twin formation via oriented attachment and subsequent transformation from anatase to rutile.

Linearly polarized light emission is analyzed in nonpolar light-emitting diodes (LEDs) covering the blue to green spectral range. In photoluminescence, m-plane GaInN/GaN structures reach a polarization ratio from 0.70 at 460 nm to 0.89 at 515 nm peak wavelength. For a-plane structures, the polarization ratio is 0.53 at 400 nm and 0.60 at 480-510 nm. In electroluminescence the polarization ratio is 0.77 at 505 nm in 350 Â 350 m 2 m-plane devices at 20 mA. Such a device should allow 44% power saving compared with nonpolarized c-plane LEDs combined with a polarizing filter, as commonly used in LED-backlit liquid crystal displays.

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Sleep patterns have been associated with the development of cancers, although the association between sleep duration and breast cancer remains controversial. The purpose of our study was to explore the relationship between sleep duration and breast cancer risk. The PubMed and Web of Science databases were searched, and restricted cubic splines were used to explore the dose-response relationship. Data from 415,865 participants were derived from 10 studies. A J-shaped nonlinear trend was found between sleep duration and breast cancer incidence (Pnon-linear = 0.012); compared with the reference hours (6 h or 7 h), with increasing sleep hours, the risk of breast cancer increased (Ptrend = 0.028). Moreover, a nonlinear relationship was found between sleep duration and estrogen receptor-positive breast cancer (Pnon-linear = 0.013); the risk of estrogen receptor-positive breast cancer increased with increasing sleep hours compared to the reference hours (Ptrend = 0.024). However, no nonlinear relationship was found between sleep duration and estrogen receptor-negative breast cancer; the risk of estrogen receptor-negative breast cancer was 1.035 for every additional sleep hour. Compared to women with the reference number of sleep hours, women with a longer sleep duration might have a significantly increased risk of breast cancer, especially estrogen receptor-positive breast cancer.