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The heavy metal-binding domain is involved in heavy metal transporting and plays a significant role in plant detoxification. However, the functions of HMAs are less well known in cotton. In this study, a total of 143 GhHMAs (heavy metal-binding domain) were detected by genome-wide identification in G. hirsutum L. All the GhHMAs were classified into four groups via phylogenetic analysis. The exon/intron structure and protein motifs indicated that each branch of the GhHMA genes was highly conserved. 212 paralogous GhHMA gene pairs were identified, and the segmental duplications were the main role to the expansion of GhHMAs. The Ka/Ks values suggested that the GhHMA gene family has undergone purifying selection during the long-term evolutionary process. GhHMA3 and GhHMA75 were located in the plasma membrane, while GhHMA26, GhHMA117 and GhHMA121 were located in the nucleus, respectively. Transcriptomic data and qRT-PCR showed that GhHMA26 exhibited different expression patterns in each tissue and during fiber development or under different abiotic stresses. Overexpressing GhHMA26 significantly promoted the elongation of leaf trichomes and also improved the tolerance to salt stress. Therefore, GhHMA26 may positively regulate fiber elongation and abiotic stress. Yeast two-hybrid assays indicated that GhHMA26 and GhHMA75 participated in multiple biological functions. Our results suggest some genes in the GhHMAs might be associated with fiber development and the abiotic stress response, which could promote further research involving functional analysis of GhHMA genes in cotton.

Vesicular silica (VS) with hierarchical structure was prepared by utilizing cationic surfactant cetyltrimethylammonium bromide (CTAB) and anionic surfactant sodium dodecyl sulfate (SDS) as the structure directing agents, and 1,3,5-triisopropylbenzene (TIPB) as the micelle expander. The resulting unilamellar and multilamellar VS with interlamellar mean mesopore size of 15–20 nm and shell thickness of 5–15 nm were used as supports for immobilization of Candida rugosa lipase (CRL) through physical adsorption. Possible mechanisms for the formation of VS and the immobilization of CRL on VS are proposed. N 2 adsorption-desorption experiments and Fourier transform infrared spectroscopy (FT-IR) measurements demonstrated that CRL was adsorbed into the curved channels of the VS. The catalytic activity, thermal stability, and reusability of VS immobilized CRL were assayed in phosphate buffer medium by hydrolysis of triacetin. The effects of pH and temperature on enzyme activity were also investigated. We report that VS immobilized CRL exhibited outstanding adaptability at higher pH and temperature, and excellent thermal stability and reusability compared with free CRL.

A novel method has been developed to design an aperture apodizer for high-power laser system. Unlike current methods having the edge serrated, the method in this paper introduces an assembly of transparent cells at the edge with varying cell size or cell pitch to modulate the transmission intensity, using gray-tone coding method as a reference. The new approach can overcome the difficulty of coordinating the long side and the short side when it comes to rectangular aperture faced by the traditional ways. Based on the scalar diffraction theory, the intensity distribution of laser beam propagating through the slot aperture with softened edge and then the spatial pinhole filter was simulated and contrasted with that of the traditional slot with sharp edge. Finally a slot structure with softened edge designed with this new method has been fabricated with a photolithographic operation.

Ordered mesoporous SBA-15 was prepared by hydrothermal process and was functionalized with(3-aminopropyl) triethoxysilane (APTES) by post-synthesis-grafting method. The materials were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectrometer (EDS), small-angle X-ray powder diffraction (SAXRD), N2 adsorption-desorption and Fourier transform infrared spectroscopy (FT-IR). The results indicated that SBA-15 had a 2-dimensional hexagonal p6mm mesoscopic structure and the mesoscopic structure was remained after the functionalization procedure. The activities of porcine pancreatic lipase (PPL) immobilized in SBA-15 by physical adsorption and in APTES functionalized SBA-15 by chemical adsorption were studied by hydrolysis of triacetin. Chemically adsorbed PPL showed higher loading amount and catalytic activity comparing with physically adsorbed PPL. The stability of immobilized PPL against thermal and pH of reaction medium was significantly improved. Recycling experiments showed that chemically adsorbed PPL exhibited better reusability than physically adsorbed PPL.