Recent baby formula milk powder contamination incidents have shown that the classic markers or standards in milk quality control are insufficient in identifying "manipulated" poor-quality milk. In the present study, we demonstrated for the first time that cow milk contains large amounts of microRNAs (miRNAs) and that the unique expression profile of milk-specific miRNAs can serve as a novel indicator and possible new standard for the quality control of raw milk and milk-related commercial products, such as fluid milk and powdered formula milk. First, using Solexa sequencing, we systematically screened miRNA expression in raw milk and identified a total of 245 miRNAs in raw milk. Unlike other classic biomarkers whose expression levels are nearly identical at different periods of lactation, individual miRNAs can be significantly altered during lactation process, implicating that miRNAs may be a more accurate indicator to reflect the quality alteration of milk. Second, using TaqMan probe-based miRNA quantitative RT-PCR, we further identified seven miRNAs that have a relatively consistent expression throughout the lactation process, and more importantly, the expression profile of these seven milk-specific miRNAs can serve as an ideal biomarker for discriminating poor-quality or "manipulated" milk from pure raw milk, as well as for the quality control of commercial milk products, such as fluid milk and powdered formula milk. Together, our findings provide a basis for understanding the physiological role of milk miRNAs and a new potential standard for determining the quality of raw milk or milk-related commercial products.

No abstract

Elegant Z-scheme WO3/Au/In2S3 nanowire arrays were precisely constructed through a facile step-by-step route. Surface potential change on pristine or In2S3-Au coated WO3 single nanowire under dark and illumination detected through a Kelvin probe force microscopy (KPFM) technique indicates that the vectorial holes transfer of In2S3 → Au → WO3 should occur upon the excitation of both WO3 and In2S3. In such charge transfer processes, the embedded Au nanoparticles in the heterojunction systems act as a charge mediator for electrons in the conduction band of WO3 and holes in the valence band of In2S3. The strong charge carrier separation ability of this structure will finally enhance the oxidation ability of WO3 with high concertation of photogenerated holes and, further, leave the free electrons in the In2S3 with long surviving time. Therefore, the unique Z-scheme WO3/Au/In2S3 heterostructure shows great visible-light activity toward photocatalytic reduction of CO2 in the presence of water vapor into renewable hydrocarbon fuel (methane: CH4).

An electric field in a photocatalytic system consisting of Au@TiO2 yolk-shell hollow spheres is created to enhance the generation of electron-hole pairs and remit the charge-carrier recombination. Local surface plasmon resonance (LSPR)-mediated local electromagnetic field nearby Au nanoparticles cannot only enhance the local generation and subsequent separation of electron-hole pairs in TiO2 shells to improve the photoreduction yield of CO2, but also facilitate chemical reactions involving multiple e(-)/H(+) transfer processes to allow the formation of high-grade carbon species (C2H6), which was rarely observed in precedent CO2 photocatalytic reduction systems. The work may provide a new viewpoint for designing photocatalysts for artificial photosynthesis involving multiple reactions.

No abstract

Although unprecedented conversion efficiency has been achieved in organic–inorganic hybrid perovskite solar cells (PSCs), their long‐term stability has remained a major issue in their transition. Here, we demonstrate a highly‐stable CH3NH3PbI3 (MAPbI3) perovskite using a green self‐assembly (SA) process that provides a major breakthrough in resolving this issue. In this process, the hydrophobic polymer, poly(methyl methacrylate) (PMMA), is introduced into the 2D layered MAPbI3 perovskite intermediates, resulting in chemical coordination and self‐assembly into 3D perovskite grains with PMMA coated along the grain boundaries. The bilayer grain boundary effectively blocks moisture corrosion thereby significantly improving the stability of MAPbI3 perovskite. Further, PMMA is found to reduce the trap density by electronically compensating the iodide vacancy along the boundary, which decreases the charge recombination and improves the open circuit voltage of PSCs. The PSCs comprising the MAPbI3−PMMA layer show excellent stability under high moisture conditions, exhibiting no phase change under ≈70% humidity for over 31 days (approximately 500% higher compared to state‐of‐the‐art) and excellent performance in 50–70% humidity for over 50 days.

The surface plasmon resonance (SPR) properties in the deep-ultraviolet (UV) to blue-light region of Al and Alcore/Al2O3shell in spherical and cylindrical nanostructures have been investigated using the discrete dipole approximation method. Simulation results show that the extremely short resonance wavelength of the Al nanostructures means the SPR is highly sensitive to the particle size and results in significant phase retardation and multipole resonance. Cylindrical Al nanoparticles show multipole resonance peaks with extremely strong intensity and narrow widths that are blue-shifted and then red-shifted with an increase in the cylinder length. An expression of the SPR peak wavelength, λmax, is derived and related to the peak shift. Cylindrical Alcore/Al2O3shell nanostructures are shown to modulate the SPR through changes to the aspect ratio and Al2O3 shell thickness. The results will assist greatly in modulating or optimizing SPR in the deep-UV to blue-light region for multimode optical filter, enhanced spectroscopy, optical lithography, and waveguide applications.

An all-solid-state Z-scheme system array consisting of an Fe2V4O13 nanoribbon (NR)/reduced graphene oxide (RGO)/CdS nanoparticle grown on the stainless-steel mesh was rationally designed for photoconversion of gaseous CO2 into renewable hydrocarbon fuels (methane: CH4).