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Graphene oxide (GO)-Ag(3)PO(4) nanocomposites synthesized through a facile solution approach via electrostatic interaction were investigated as excellent photocatalysts for the degradation of rhodamine B (RhB) under visible light irradiation. SEM and TEM observations indicate that Ag(3)PO(4) nanospheres of ~120 nm in diameter were well dispersed and anchored onto the exfoliated GO sheets. The characterizations of FTIR and Raman demonstrated the existence of strong charge interactions between GO sheets and Ag(3)PO(4) nanospheres. As compared to Ag(3)PO(4) nanospheres alone, the attachments of GO sheets led to a band gap narrowing (2.10 eV) and a strong absorbance in the near infrared region (NIR). The photoluminescence (PL) analysis indicates a more efficient separation of electron-hole pairs in the GO-Ag(3)PO(4) nanocomposites. Notably, the incorporation of GO sheets not only significantly enhances the photocatalytic activity but also improves the structural stability of Ag(3)PO(4). The positive synergistic effects between Ag(3)PO(4) nanospheres and GO sheets are proposed to contribute to the improved photocatalytic properties. A possible photocatalytic mechanism of the GO-Ag(3)PO(4) nanocomposites was assumed as well. The integration of these advantages enables such GO-Ag(3)PO(4) hybrid material to be a nice photocatalyst for broad applications in a sewage treatment system.

Uniform hierarchical Ag 3 PO 4 porous microcubes were for the first time synthesized by a one-step reaction at room temperature with the help of the trisodium citrate (Na 3 Cit). The phase, microstructure, morphology, and textural properties of the Ag 3 PO 4 porous microcubes were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and UV-vis diffuse reflectance spectroscopy (DRS). Na 3 Cit played important roles as the structure directing agent, crystal growth modifier and aggregation-orienting agent for the formation of this unique Ag 3 PO 4 microstructure. Ostwald ripening and the self-assembly process were proposed for the possible evolution mechanism based on time-dependent experiments. Importantly, the obtained Ag 3 PO 4 porous microcubes exhibited remarkable enhanced visible-light photocatalytic degradations of an aqueous solution of rhodamine B (RhB), far exceeding that of solid Ag 3 PO 4 sample and commercial P25 powders. The results presented here also provide new insights into porous hierarchical materials as high-performance visible-light photocatalysts and their potential use in environmental protection.

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In this study, a new empirical model is proposed for estimating daily global solar radiation on a horizontal surface by the day of the year. The performance of the proposed model is validated by comparing with three trigonometric correlations at nine representative stations of China using statistical error tests such as the mean absolute percentage error (MAPE), mean absolute bias error (MABE), root mean square error (RMSE) and correlation coefficients (r). The results show that the new model provides better estimation and has good adaptability to highly variable weather conditions. Then the application of the methodology is performed for the other 70 meteorological stations across China.

The rice blast fungus Magnaporthe oryzae causes a devastating disease that threatens global rice (Oryza sativa) production. Despite intense study, the biology of plant tissue invasion during blast disease remains poorly understood. Here we report a high resolution, transcriptional profiling study of the entire plant-associated development of the blast fungus. Our analysis revealed major temporal changes in fungal gene expression during plant infection. Pathogen gene expression could be classified into 10 modules of temporally co-expressed genes, providing evidence for the induction of pronounced shifts in primary and secondary metabolism, cell signalling and transcriptional regulation. A set of 863 genes encoding secreted proteins are differentially expressed at specific stages of infection, and 546 genes named MEP (Magnaporthe  effector protein) genes were predicted to encode effectors. Computational prediction of structurally-related MEPs, including the MAX effector family, revealed their temporal co-regulation in the same co-expression modules. We characterised 32 MEP genes and demonstrate that Mep effectors are predominantly targeted to the cytoplasm of rice cells via the biotrophic interfacial complex (BIC) and use a common unconventional secretory pathway. Taken together, our study reveals major changes in gene expression associated with blast disease and identifies a diverse repertoire of effectors critical for successful infection.

Electrochemical CO reduction (ECR) offers an important pathway for renewable energy storage and fuels production. It still remains a challenge in designing highly selective, energy-efficient, robust, and cost-effective electrocatalysts to facilitate this kinetically slow process. Metal-free carbon-based materials have features of low cost, good electrical conductivity, renewability, diverse structure, and tunability in surface chemistry. In particular, surface functionalization of carbon materials, for example by doping with heteroatoms, enables access to unique active site architectures for CO adsorption and activation, leading to interesting catalytic performances in ECR. We aim to provide a comprehensive review of this category of metal-free catalysts for ECR, providing discussions and/or comparisons among different nonmetallic catalysts, and also possible origin of catalytic activity. Fundamentals and some future challenges are also described.

An insertional mutagenesis screen was used to investigate the biology of plant infection by the devastating rice blast pathogen, Magnaporthe oryzae. Here, we report the identification of a new mutant, LY-130, which is defective in multiple steps during infection-related morphogenesis and pathogenicity. Analysis of the mutation confirmed an insertion into gene MoRIC8, which encodes a 480-amino-acid protein that is a putative homologue of the Ric8 regulator of GTP-binding protein (G-protein) signaling, previously described in animals. Targeted gene deletion mutants of MoRIC8 were nonpathogenic and impaired in cellular differentiation associated with sporulation, sexual development, and plant infection. MoRic8 physically interacts with the Galpha subunit MagB in yeast two-hybrid assays and appears to act upstream of the cyclic AMP response pathway that is necessary for appressorium morphogenesis. Taken together, our results indicate that MoRic8 may act as a novel regulator of the G-protein signaling during infection-related development of rice blast fungus M. oryzae.