Genome-wide characterization of L-aspartate oxidase genes in wheat and their potential roles in the responses to wheat disease and abiotic stresses.

L-aspartate oxidase (AO) is the first enzyme in NAD+ biosynthesis and is widely distributed in plants, animals, and microorganisms. Recently, AO family members have been reported in several plants, including Arabidopsis thaliana and Zea mays. Research on AO in these plants has revealed that AO plays important roles in plant growth, development, and biotic stresses; however, the nature and functions of AO proteins in wheat are still unclear. In this study, nine AO genes were identified in the wheat genome via sequence alignment and conserved protein domain analysis. These nine wheat AO genes (TaAOs) were distributed on chromosomes 2, 5, and 6 of sub-genomes A, B, and D. Analysis of the phylogenetic relationships, conserved motifs, and gene structure showed that the nine TaAOs were clustered into three groups, and the TaAOs in each group had similar conserved motifs and gene structure. Meanwhile, the subcellular localization analysis of transient expression mediated by Agrobacterium tumetioniens indicated that TaAO3-6D was localized to chloroplasts. Prediction of cis-elements indicated that a large number of cis-elements involved in responses to ABA, SA, and antioxidants/electrophiles, as well as photoregulatory responses, were found in TaAO promoters, which suggests that the expression of TaAOs may be regulated by these factors. Finally, transcriptome and real-time PCR analysis showed that the expression of TaAOs belonging to Group III was strongly induced in wheat infected by F. graminearum during anthesis, while the expression of TaAOs belonging to Group I was heavily suppressed. Additionally, the inducible expression of TaAOs belonging to Group III during anthesis in wheat spikelets infected by F. graminearum was repressed by ABA. Finally, expression of almost all TaAOs was induced by exposure to cold treatment. These results indicate that TaAOs may participate in the response of wheat to F. graminearum infection and cold stress, and ABA may play a negative role in this process. This study lays a foundation for further investigation of TaAO genes and provides novel insights into their biological functions.

High Performance 3D Self-Supporting Cu-Bi Aerogels for Electrocatalytic Reduction of CO2 to Formate.

The electrocatalytic reduction of CO2 (CO2 RR) to CO, formate, methane, and other high-value compounds is a promising technique. However, current electrocatalysts suffer from drawbacks such as few active catalytic sites, poor selectivity and low stability, etc, which restrict the practical application. Although monatomic metal catalysts have been widely reported in recent years, high performance non-noble metal aerogels were rarely investigated for electrocatalytic CO2 RR. Herein, Cu-Bi aerogels with boosted CO2 RR activity were well constructed by a simple one-step self-assembly method. The resultant Cu1 Bi2 exhibits excellent CO2 RR activity with high faradaic efficiency (FE) of 96.57 % towards HCOOH at a potential of -0.9 V vs. RHE, and the FEHCOOH remains over 80.18 % in a wide potential window (-0.8 V to -1.2 V vs. RHE). It demonstrated that the enhanced CO2 RR activity of Cu-Bi aerogels could be attributed to the 3D self-supporting structure of the catalysis, synergistic effect, and low interfacial charge transfer resistance.

In-Situ Synthesis of Hydrophobic Polyurethane Ternary Composite Induced by Hydroxyethyl Cellulose through A Green Method for Efficient Oil Removal.

Hydroxyethyl cellulose (HEC) was introduced to activate the surface of polyurethane (PU) sponge to successfully prepare a hydrophobic ternary composite PU/HEC/SiO2. The hydrophobic layer of the composite was realized by in-situ polymerization of methyltriethoxysilane (MTES) onto the surface of PU sponge. The formation of a stable hydrophobic SiO2 layer solved successfully the problem of ease of SiO2 particles shedding from the composite. Moreover, the amphiphilic molecules produced by the hydrolysis of MTES monomers facilitated the preparation of hydrophobic materials by aqueous dispersion polymerization. Aqueous synthesis made the reaction process environmentally-friendly and pollution-free. The as-prepared composite PU/HEC/SiO2 not only retains high porosity and low density of the PU sponge, but also considerably reduced the surface free energy and increased the surface roughness of the PU sponge. Therefore, outstanding hydrophobicity and high porosity endow the composite with excellent oil removal capability as a high-efficiency absorbent. Moreover, the hydrophobic composite that had absorbed oil could be regenerated easily by squeezing and recycling.

Modes of Fe Incorporation in Co-Fe (Oxy)hydroxide Oxygen Evolution Electrocatalysts.

Ni-Fe (oxy)hydroxide and Co-Fe (oxy)hydroxide are among the most active oxygen evolution reaction (OER) catalysts in alkaline media. Fe is essential for the high activity, but the details of how Fe is incorporated into the Ni or Co (oxy)hydroxide structure and affects catalysis remain incompletely understood. This study concerns two different modes of Fe incorporation to form Co(Fe)Ox Hy , which both yield increased OER activity but result in Fe and Co species that differ in chemical reactivity and electrochemical response. Co(Fe)Ox Hy films that were cathodically deposited from mixed Co and Fe nitrate solution (co-deposited) result in Fe species that interact strongly with the Co species (as evidenced by an anodic shift in the Co redox wave) and are difficult to leach out under electrochemical conditions. Fe incorporated into a CoOx Hy film by cycling in Fe-spiked KOH electrolyte similarly enhance activity, but do not strongly electronically interact with the majority of the Co in the film and are removed by cycling in Fe-free KOH. These results support the hypothesis that co-deposition of Co(Fe)Ox Hy leads to films where the Co and Fe are mixed within the nanosheet structure and cycling in Fe-spiked KOH incorporates Fe species largely at surface, edge, or defect sites, where they drive OER but do not otherwise significantly modulate the electrochemical response of the Co.

Surface modification of bacterial cellulose aerogels' web-like skeleton for oil/water separation.

The cellulose nanofibers of bacterial cellulose aerogel (BCA) are modified only on their surfaces using a trimethylsilylation reaction with trimethyichlorosilane in liquid phase followed by freeze-drying. The obtained hydrophobic bacterial cellulose aerogels (HBCAs) exhibit low density (≤6.77 mg/cm(3)), high surface area (≥169.1 m(2)/g), and high porosity (≈ 99.6%), which are nearly the same as those of BCA owing to the low degrees of substitution (≤0.132). Because the surface energy of cellulose nanofibers decreased and the three-dimensional web-like microstructure, which was comprised of ultrathin (20-80 nm) cellulose nanofibers, is maintained during the trimethylsilylation process, the HBCAs have hydrophobic and oleophilic properties (water/air contact angle as high as 146.5°) that endow them with excellent selectivity for oil adsorption from water. The HBCAs are able to collect a wide range of organic solvents and oils with absorption capacities up to 185 g/g, which depends on the density of the liquids. Hence, the HBCAs are wonderful candidates for oil absorbents to clean oil spills in the marine environment. This work provides a different way to multifunctionalize cellulose aerogel blocks in addition to chemical vapor deposition method.

Facile shape control of Co(3)O(4) and the effect of the crystal plane on electrochemical performance.

Co(3)O(4) with three different crystal plane structures - cubes bounded by {001}planes, truncated octahedra enclosed by {111} and {001} planes, and octahedra with exposed {111}planes - is synthesized using a very simple one-step hydrothermal method. The three kinds of Co(3)O(4) exhibit significantly different electrochemical performances and the effect of different exposed crystal planes on the electrochemical performance of Co(3)O(4) is comprehensively studied.

Photocontrollable J-aggregation of a diarylethene-phthalocyanine hybrid and its aggregation-stabilized photochromic behavior.

The photocontrollable J-aggregation of a diarylethene-phthalocyanine hybrid (T-ZnPc) and its aggregation-stabilized photochromic behavior were investigated by various techniques. T-ZnPc initially exhibited slight J-aggregation tendency in solvents such as chloroform and toluene through conformational planarization effect, but formed much stronger J-aggregates upon the illumination of 254 nm UV light. In darkness, the UV-irradiated solutions gradually returned to their initial state. These phenomena can be explained by the pronounced change in molecular planarity accompanying the reversible isomerization of the diarylethene units of T-ZnPc. Besides, we have found that the thermal stability of the closed-ring diarylethene isomers in molecularly dispersed T-ZnPc is much poorer than that in aggregates. As long as the aggregates were broken, they converted to corresponding open-ring form instantly. This study provided an example of fully photocontrollable aggregation of phthalocyanines and paved a new way for improving the stability of the photochromic systems.

Ag nanoparticles coated SWCNT with surface enhanced Raman scattering (SERS) signals.

We report here a simple method to fabricate the silver nanoparticles (AgNPs) coated DNA-SWCNTs that give SERS signals. Dynamic light scattering (DLS), atomic force microscopy (AFM), and high resolution transmission electron microscopy (HRTEM) suggested the products are dispersive and soluble in aqueous solution. The Raman scattering spectra show AgNPs coated SWCNTs have enhanced the Raman signal when compared with pure SWCNT. From the radial breathing mode (RBM) of the Raman spectra, we can disclose that this DNA-SWCNT has unique chirality, which implies that it could be a good nanoprobe for cell marking.

Free-standing array of multi-walled carbon nanotubes on silicon (111) by a field-inducing self-assembly process.

In this paper, the authors bring forward a novel method named as the field-inducing self-assembly process in which free-standing MWCNTs array can be assembled perpendicularly on silicon (111) wafer. The density of free-standing MWCNTs array is controllable by adjusting the DC voltage from 0 V to 40 V. Preferential MWCNTs array is obtained by the condensation reaction between carboxylic group of MWCNTs end and hydroxyl group of silicon electrode surface under a low DC field. And the MWCNTs array can exhibit excellent field emission property.

Fabrication of hierarchical CaCO3 mesoporous spheres: particle-mediated self-organization induced by biphase interfaces and SAMs.

Highly ordered hierarchical calcium carbonate is an important phase involved in calcification by a wide variety of invertebrate organisms, and its formation is of technological interest in the development of functional materials. In this article, porous CaCO(3) hierarchical microspheres with a hedgehoglike appearance have been fabricated on the flexible substrate under mild conditions. There are two points that play important roles in the regular organization of the terminal products: one is the biphase interfaces, which are generated by organic solvent n-hexane and an aqueous saturated solution of Ca(OH)(2), and the other is hydroxyl-terminated monolayers assembled on the flexible PET (poly(ethylene terephthalate)) substrate. The SEM images show that novel CaCO(3) hierarchical microspheres consist of densely stacked "shuttles" by the oriented self-organization of CaCO(3) nanoparticles. The IR and XRD spectra indicate that the as-synthesized products are composed of a calcite phase obtained by an ACC (amorphous calcium carbonate)-to-calcite transformation. In view of the results, a nanoparticle-mediated self-organization process induced by biphase interfaces and SAMs template is proposed for the integration of functional materials and nanodevices.

Fabrication of self-assembled monolayers (SAMs) and inorganic micropattern on flexible polymer substrate.

By grafting (aminopropyl)triethoxysilane (APTES) as the buffer layer on poly(ethylene terephthalate) (PET) surface, the SAMs ofoctadecyltrichlorosilane (OTS), phenyltrichlorosilane (PTCS), vinyltrichlorosilane (VTCS), andp-tolyltrichlorosilane (TTCS) were fabricated on the flexible polymer substrate. The properties of SAMs were accurately controlled by adjusting the immersing time of substrates in the solutions and the concentration of the solutions. The SAMs acted as templates, and TiO2 micropattern was successfully deposited on OTS, TTCS, and PTCS SAMs.