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The treatment of dye polluting water is one of the most important tasks that are concerned with water resources. Herein, a nanofiber composite membrane (NCM) is fabricated with an aim to effectively degrade organic dyes. First, α‐Fe2O3 nanoparticles are loaded on the surface of graphene oxide (GO) sheets through hydrothermal method. Then the as‐prepared α‐Fe2O3@rGO sheets are deposited on polyacrylonitrile (PAN) nanofiber mat via vacuum filtration to obtain α‐Fe2O3@rGO/PAN NCM. Thus, the NCM has a double‐layer structure with α‐Fe2O3@rGO as the upper layer and PAN nanofiber as the lower layer (support layer), providing structural advantages in photocatalytic degradation in solution. The composition, morphology, and structure of the NCM are characterized in detail. Photocatalytic experiments show that the NCM can effectively degrade a variety of organic dyes, among which the degradation rate of methylene blue is as high as 98.5% within 2 h. Moreover, the degradation rate still remains at high level after 5 cycles and the NCM remains intact, indicating the reusability of the NCM. It is in particular worth highlighting that high degradation efficiency is obtained even under natural sunlight, demonstrating great potential applications of the NCM in industrial dye wastewater treatment.

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The development and maturation of maize kernel involves meticulous and fine gene regulation at transcriptional and post-transcriptional levels, and miRNAs play important roles during this process. Although a number of miRNAs have been identified in maize seed, the ones involved in the early development of grains and in different lines of maize have not been well studied. Here, we profiled four small RNA libraries, each constructed from groups of immature grains of Zea mays inbred line Chang 7–2 collected 4–6, 7–9, 12–14, and 18–23 days after pollination (DAP). A total of 40 known (containing 111 unique miRNAs) and 162 novel (containing 196 unique miRNA candidates) miRNA families were identified. For conserved and novel miRNAs with over 100 total reads, 44% had higher accumulation before the 9th DAP, especially miR166 family members. 42% of miRNAs had highest accumulation during 12–14 DAP (which is the transition stage from embryogenesis to nutrient storage). Only 14% of miRNAs had higher expression 18–23 DAP. Prediction of potential targets of all miRNAs showed that 165 miRNA families had 377 target genes. For miR164 and miR166, we showed that the transcriptional levels of their target genes were significantly decreased when co-expressed with their cognate miRNA precursors in vivo. Further analysis shows miR159, miR164, miR166, miR171, miR390, miR399, and miR529 families have putative roles in the embryogenesis of maize grain development by participating in transcriptional regulation and morphogenesis, while miR167 and miR528 families participate in metabolism process and stress response during nutrient storage. Our study is the first to present an integrated dynamic expression pattern of miRNAs during maize kernel formation and maturation.

A subgroup H of a group G is called semipermutable if it is permutable with every subgroup K of G with H K = 1. H is said to be s-semipermutable if it is permutable with every Sylow p-subgroup of G with p H = 1. In this article, we investigate the p-nilpotency of a group for which every maximal subgroup of its Sylow p-subgroups is s-semipermutable for some prime p. We generalize some recent theorems in Guo and Shum (2003).