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In this study, we report that the carrier mobility of 2%-La-doped BaSnO 3 (LBSO) films on (001) SrTiO 3 and (001) MgO substrates strongly depends on the thickness whereas it is unrelated to the film/substrate lattice mismatch (+5.4 % for SrTiO 3 , −2.3 % for MgO). The films exhibited large differences in the lattice parameters, the lateral grain sizes (~85 nm for SrTiO 3 , ~20 nm for MgO), the surface morphologies, the threading dislocation densities, and the misfit dislocation densities. However, the mobility dependences on the film thickness in both cases were almost the same, saturating at ~100 cm 2 V −1 s −1 while the charge carrier densities approached the nominal carrier concentration (=[2 % La 3+ ]). Our study clearly indicates that the carrier mobility in LBSO films strongly depends on the thickness. These results would be beneficial for understanding the carrier transport properties and fruitful to further enhance the mobility of LBSO films.program funded from following programs of each country: International

Novel alternative antibacterial compounds have been persistently explored from plants as natural sources to overcome antibiotic resistance leading to serious foodborne bacterial illnesses. In this study, the ethanolic extracts from 239 traditional Chinese medicinal plants (TCMP)’ materials were screened to discover promising candidates that have strong antibacterial properties against multidrug-resistant Staphylococcus (S.) aureus and low cytotoxicity. The results revealed that 74 extracts exhibited good antibacterial activities (diameter of inhibition zone (DIZ) ≥ 15 mm). Furthermore, 18 extracts (DIZ ≥ 20 mm) were determined their minimum inhibitory concentrations (MIC) and minimum bactericide concentrations (MBC), ranging from 0.1 to 12.5 mg/mL and 0.78 to 25 mg/mL, respectively. In addition, most of the 18 extracts showed relatively low cytotoxicity (a median lethal concentration (LC50) >100 µg/mL). The 18 extracts were further determined to estimate possible correlation of their phenolic contents with antibacterial activity, and the results did not show any significant correlation. In conclusion, this study selected out some promising antibacterial TCMP extracts with low cytotoxicity, including Rhus chinensis Mill., Ilex rotunda Thunb., Leontice kiangnanensis P.L.Chiu, Oroxylum indicum Vent., Isatis tinctorial L., Terminalia chebula Retz., Acacia catechu (L.f.) Willd., Spatholobus suberectus Dunn, Rabdosia rubescens (Hemsl.) H.Hara, Salvia miltiorrhiza Bunge, Fraxinus fallax Lingelsh, Coptis chinensis Franch., Agrimonia Pilosa Ledeb., and Phellodendron chinense C.K.Schneid.

Although spice extracts are well known to exhibit antibacterial properties, there is lack of a comprehensive evaluation of the antibacterial effect of spices against antibiotic-resistant bacteria. In the present study, ethanolic extracts from a total of 67 spices were comprehensively investigated for their in vitro antibacterial activities by agar well diffusion against two common food-borne bacteria, Staphylococcus aureus and Salmonella enteritidis, with multi-drug resistance. Results showed that S. aureus was generally more sensitive to spice extracts than S. enteritidis. Of the 67 spice extracts, 38 exhibited antibacterial activity against drug-resistant S. aureus, while only four samples were effective on drug-resistant S. enteritidis. In addition, 11 spice extracts with inhibition zones greater than 15 mm were further verified for their broad-spectrum antibacterial properties using another 10 drug-resistant S. aureus strains. It was found that five spice extracts, including galangal, fructus galangae, cinnamon, yellow mustard seed, and rosemary, exhibited the highest antibacterial capacity. Further cytotoxicity of these 11 spices was determined and LC50 values were found to be more than 100 μg/mL except for galangal, rosemary, and sage, whose LC50 values were 9.32 ± 0.83, 19.77 ± 2.17, and 50.54 ± 2.57, respectively. Moreover, the antioxidant activities (ferric-reducing antioxidant power (FRAP) and trolox equivalent antioxidant capacity (TEAC) values) and total phenolic content (TPC) of spice extracts were determined to establish possible correlations with the antibacterial activity. Although the antibacterial effect was positively correlated with the antioxidant activities and TPC, the correlation was weak (r < 0.5), indicating that the antibacterial activity could also be attributed to other components besides antioxidant polyphenols in the tested spice extracts. In conclusion, dietary spices are good natural sources of antibacterial agents to fight against antibiotic-resistant bacteria, with potential applications as natural food preservatives and natural alternatives to antibiotics in animal feeding.

Polycrystalline anatase titanium dioxide has drawn great interest, because of its potential applications in highefficiency photovoltaics and photocatalysts. There has been speculation on the electronic properties of grain boundaries but little direct evidence, because grain boundaries in anatase are challenging to probe experimentally and to model. We present a combined experimental and theoretical study of anatase grain boundaries that have been fabricated by epitaxial growth on a bicrystalline substrate, allowing accurate atomic-scale models to be determined. The electronic structure in the vicinity of stoichiometric grain boundaries is relatively benign to device performance but segregation of oxygen vacancies introduces barriers to electron transport, because of the development of a space charge region. An intrinsically oxygen-deficient boundary exhibits charge trapping consistent with electron energy loss spectroscopy measurements. We discuss strategies for the synthesis of polycrystalline anatase in order to minimize the formation of such deleterious grain boundaries.

Transparent oxide semiconductors (TOSs) showing both high visible transparency andhigh electron mobility have attracted great attention towards the realization of advanced optoelectronic devices. 1-5 La-doped BaSnO 3 (LBSO) is one of the most promising TOSs because its single crystal exhibits a high electron mobility. 6-9 However, in the LBSO films, it is very hard to obtain high mobility due to the threading dislocations, which are originated from the lattice mismatch between the film and the substrate. Therefore, many researchers have tried to improve the mobility by inserting a buffer layer 6, 10-14 .While the buffer layers increased the electron mobilities, this approach leaves much to be desired since it involves a two-step film fabrication process and the enhanced mobility values are still significantly lower than single crystal values. We show herein that the electron mobility of LBSO films can be improved without inserting any buffer layers if the films are grown under highly oxidative ozone (O 3 ) atmospheres. The O 3 environments relaxed the LBSO lattice and reduced the formation of Sn 2+ states, which are known to suppress the electron mobility in LBSO. 15 The resultant O 3 -LBSO films showed improved mobility values up to 115 cm 2 V −1 s −1 , which is among the highest in LBSO films on SrTiO 3 substrates and comparable to LBSO films with buffer layers. Perovskite transparent oxide BaSnO 3 has attracted great interest since substituting La in Ba sites turns it to an n-type degenerate semiconductor with a very high electrical conductivity and electron mobility. Studies have shown that La-doped BaSnO 3 (La x Ba 1−x SnO 3, LBSO)single crystals can exhibit a high electrical conductivity (~10 4 S cm −1 ) and electron mobility (320 cm 2 V −1 s −1 ) 6, 7 with a carrier concentration of 8 × 10 19 cm −3 at room temperature (RT).Although the bandgap (E g ) of BaSnO 3 is ~3.1 eV, the E g of LBSO is ~3.5 eV due to the Burstein-Moss shift 8,9 . Since these properties are attractive for designing next generation transparent thin film electronic devices, 1, 4, 5 the electrical transport properties of thin LBSO epitaxial films have been examined many times. However, the electron mobility values in LBSO films are widely scattered from 10 to 183 cm 2 V −1 s −1 , which are much lower than the single crystal values. 6,[10][11][12][13][14] Many reports attribute the mobility suppression to the charge carrier propagation hindrance at threading dislocations or grain boundaries, which are mainly caused by the lattice mismatch at the film/substrate interface [16][17][18][19] . Therefore, many researchers inserted thick insulating buffer layers between doped BaSnO 3 film and substrate to reduce the threading dislocations. For example, A. Prakash et al. 13 optimized the thickness of buffer and La doped BSO layer and