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This study is the first to explore the effect of selenium doping on the electronic properties of β-Ga2O3 through first-principles calculations. Selenium doping in β-Ga2O3 is a significant choice, as it has the potential to improve the material's electronic properties. Previous work on β-Ga2O3 has focused primarily on other dopants, and the effect of selenium doping is not well understood. Therefore, this study fills an important gap in the current understanding of β-Ga2O3 doping. Selenium doping in β-Ga2O3 was studied by first-principles calculations with a hybrid functional, as this functional can offer a more accurate description of electronic properties, resulting in accurate electronic bandgap and defect level calculations. Our first-principles calculations reveal that selenium can be incorporated on both Ga and O sites under specific conditions. Specifically, under O-rich conditions, selenium atoms are more likely to substitute the Ga sites, whereas under Ga-rich conditions, they are more likely to substitute the O sites. With the formation energy analysis, our findings indicate that selenium doping on Ga sites can lead to n-type conductivity, with it acting as shallow donor. On the other hand, Se dopants at the O sites exhibit deep donor characteristics, rendering it ineffective in regulating the conductivity of β-Ga2O3 materials. Our findings suggest that Se can be used as a dopant to tune the β-Ga2O3 conductivity for electronic and photonic applications, provided that the atomic substitution on Ga sites can be effectively controlled. Our results will provide valuable theoretical insights for the refined use of selenium dopants in β-Ga2O3, as well as guidance and theoretical support for subsequent researchers in the selection of Ga2O3 dopants. [ABSTRACT FROM AUTHOR]

This study aims at suggesting an end-to-end algorithm based on a U-net-optimized generative adversarial network to predict anterior neck lower jaw angles (ANLJA), which are employed to define fetal head posture (FHP) during nuchal translucency (NT) measurement. We prospectively collected 720 FHP images (half hyperextension and half normal posture) and regarded manual measurement as the gold standard. Seventy percent of the FHP images (half hyperextension and half normal posture) were used to fit models, and the rest to evaluate them in the hyperextension group, normal posture group (NPG), and total group. The root mean square error, explained variation, and mean absolute percentage error (MAPE) were utilized for the validity assessment; the two-sample t test, Mann–Whitney U test, Wilcoxon signed-rank test, Bland–Altman plot, and intraclass correlation coefficient (ICC) for the reliability evaluation. Our suggested algorithm outperformed all the competitors in all groups and indices regarding validity, except for the MAPE, where the Inception-v3 surpassed ours in the NPG. The two-sample t test and Mann–Whitney U test indicated no significant difference between the suggested method and the gold standard in group-level comparison. The Wilcoxon signed-rank test revealed significant differences between our new approach and the gold standard in personal-level comparison. All points in Bland–Altman plots fell between the upper and lower limits of agreement. The inter-ICCs of ultrasonographers, our proposed algorithm, and its opponents were graded good reliability, good or moderate reliability, and moderate or poor reliability, respectively. Our proposed approach surpasses the competition and is as reliable as manual measurement. [ABSTRACT FROM AUTHOR]

Here, we fabricated In2O3(ZnO)m (IZO) superlattice microplates with hexagon morphologies by the substrate-free optical vapor supersaturated precipitation. The IZO microplates possessed a superlattice structure with a large m number, i.e., m = 23, consisting of layered alternating stacks of octahedral InO2− as inversion boundaries and layered InZnmOm+1+ as a zig-zag modulated pattern. The Raman peak at 613 cm−1 confirmed the superlattice of the IZO microplates. The broad asymmetric excitonic photoluminescence (PL) emission with the photon energy of 3.236 eV indicated the heavy doping of indium in the IZO, resulting a redshift of ~ 32 meV from the near-band-edge emission. The unusual negative thermal quenching of PL intensity was also observed. Moreover, the anisotropic electrical properties of the IZO superlattice microplates were manifested, for the first time, where the in-plane conductivity was two orders of magnitude higher than out-plane one. The present work provided new insight into the free-standing IZO superlattice microdevices for future optoelectronic applications. [ABSTRACT FROM AUTHOR]