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Incorporating antibacterial agent into biomimetic coating inspired by natural organisms with micro-nano structure surface has generated more interest for antifouling applications. In this work, poly(dimethylsiloxane) (PDMS)-based triblock copolymers and sub-20 nm nanoparticles Ag and heterogeneous Fe3O4-coated Ag (Fe3O4@Ag) were used to construct microphase separation topography with oriented copolymer blocks structure. The artificial surface was verified by atomic force microscopy and scanning electron microscopy images. Meanwhile, the surface exhibited relative stable hydrophobic property, which was demonstrated by the water contact angle and dynamic air-bubble contact angle measurements. Consequently, after immersed in BSA solution 24 h and 720 h, the actual BSA absorption amount of the surface with Fe3O4@Ag nanoparticles was as low as 10 % and 27 % that of the initial BSA amount, respectively. Moreover, the surface also showed remarkable antibacterial performance, which effectively suppressed the growth rate of Escherichia coli. The strategy of constructing the flexible microphase separation structure by introducing heterogeneous inorganic antibacterial nanoparticles into a block copolymer substrate opens up a new way to create an antifouling surface coating.

Grain size and shape are important factors in determining the grain yield. In this study, OsNF-YC10, a member of the NF-Y transcription factor family encoding a putative histone transcription factor, was cloned and characterized. qRT-PCR and mRNA in situ hybridization analysis revealed that OsNF-YC10 was highly expressed in endosperm and spikelet hull at late developmental stages. The results showed that OsNF-YC10 was a nuclear protein showing transcription activation activity. The osnf-yc10 lines, produced using CRISPR/Cas9 technology, showed narrow, thin and light grains. Cytological experiments revealed significantly reduced cell number of spikelet hull in osnf-yc10 lines compared with that in WT. Narrow, thin, and light grains were found consistently in OsNF-YC10 RNAi transgenic lines. Moreover, the number of cells decreased in the grain-width direction than WT. These results indicated that OsNF-YC10 plays an important role in determining grain size and shape. OsNF-YC10 was further revealed to influence the expression of GW8 (a positive regulator of grain width), GW7 (a negative regulator of grain width) and cell cycle-regulated genes CYCD4, CYCA2.1, CYCB2.1, CYCB2.2, E2F2. Taken together, it is suggested that OsNF-YC10 regulates the grains size and shape by influencing the cell proliferation of spikelet hulls.