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As a promising thermochromic material for smart windows, VO2-based films have received extensive attention. To enhance the luminous transmittance (Tlum) of thermochromic smart windows without seriously affecting the solar modulation efficiency (ΔTsol), this paper prepared VO2 films by rapid thermal annealing of sputtered vanadium thin films on an ordered SiO2 nanosphere array, and then the ITO as antireflection layer was deposited on VO2 film by reactive magnetron sputtering. The surface morphology, crystal structure and optical transmittance of the films were characterized by Scanning Electron Microscopy, X-ray diffraction and UV–VIS–NIR spectrophotometer, respectively. The SiO2 nanospheres provide continuous refractive index gradient, while the deposition of the ITO antireflection layer creates conditions for thin film interference, thereby synergistically reducing surface reflection in the VO2-based smart window. Compared with the planar VO2 thin film (Tlum, 39.1%), the ITO/VO2/SiO2 composite structure can significantly increase the Tlum from 39.1 to 55.5%, an increase of nearly 16.4%, while the ΔTsol is basically unchanged. The results provide an effective strategy for improving the performance of smart windows. [ABSTRACT FROM AUTHOR]

The trapping stiffness and width are two important parameters to characterize a counter-propagating dual-beam optical trap. We present two types of asymmetric counter-propagating dual-beam optical trap with the different numerical aperture (NA) and trapping power to eliminate the multi-equilibrium positions when two foci of the optical trap are not coincided. Meanwhile, the asymmetric dual-beam trap with the different NA enhances the axial trapping width and stiffness over five and three times, respectively, higher than the standard dual-beam trap with the higher and same average NA. Besides, it increases the transverse trapping stiffness when two foci are not coincided. The asymmetric dual-beam optical trap will benefit the future applications for the study of precision measurement, basic physics and biomaterials. [ABSTRACT FROM AUTHOR]

The regeneration from embryogenic callus of higher plants in tissue culture is regulated by explants types and developmental stage and also regulated by some genes. In Miscanthus lutarioriparius, five candidate genes were selected to decide the differential expression between embryogenic and non-embryogenic calli, including MlARF-GEP (guanine nucleotide-exchange protein of ADP ribosylation factor), MlKHCP (kinesin heavy chain like protein), MlSERK1 (somatic embryogenesis receptor-like kinases 1), MlSERK2 (somatic embryogenesis reportor-like kinases 2), and MlTypA (tyrosine phosphorylation protein A) with Genbank accession numbers KU640196–KU640200. Multiple sequence alignment analysis showed that five genes were highly conserved among members of their gene families respectively. Phylogenetic relationship analysis showed that five genes were closest with homologous genes of Zea mays and Sorghum. The qRT-PCR results showed significant differences of five genes expression pattern between two different callus types, the relative expression in embryogenic callus was detected to exceed in non-embryogenic callus. Furthermore, simple sequence repeats (SSR) marker statistics results via Chi-square showed a significant correlation between MlSERK1 genotype and induction of embryogenic callus in M. lutarioriparius. This study may lay the foundation of the molecular mechanism on the embryogenic callus induction of M. lutarioriparius and perhaps provide some gist for further study on genetic manipulation. [ABSTRACT FROM AUTHOR]

Furanic and phenolic compounds are problematic compounds resulting from the pretreatment of lignocellulosic biomass for biofuel production. Microbial electrolysis cell (MEC) is a promising technology to convert furanic and phenolic compounds to renewable H2. The objective of the research presented here was to elucidate the processes and electron equivalents flow during the conversion of two furanic (furfural, FF; 5-hydroxymethyl furfural, HMF) and three phenolic (syringic acid, SA; vanillic acid, VA; 4-hydroxybenzoic acid, HBA) compounds in the MEC bioanode. Cyclic voltammograms of the bioanode demonstrated that purely electrochemical reactions in the biofilm attached to the electrode were negligible. Instead, microbial reactions related to the biotransformation of the five parent compounds (i.e., fermentation followed by exoelectrogenesis) were the primary processes resulting in the electron equivalents flow in the MEC bioanode. A mass-based framework of substrate utilization and electron flow was developed to quantify the distribution of the electron equivalents among the bioanode processes, including biomass growth for each of the five parent compounds. Using input parameters of anode efficiency and biomass observed yield coefficients, it was estimated that more than 50% of the SA, FF, and HMF electron equivalents were converted to current. In contrast, only 12 and 9% of VA and HBA electron equivalents, respectively, resulted in current production, while 76 and 79% remained as fermentation end products not further utilized in exoelectrogenesis. For all five compounds, it was estimated that 10% of the initially added electron equivalents were used for fermentative biomass synthesis, while 2 to 13% were used for exoelectrogenic biomass synthesis. The proposed mass-based framework provides a foundation for the simulation of bioanode processes to guide the optimization of MECs converting biomass-derived waste streams to renewable H2. [ABSTRACT FROM AUTHOR]

Eukaryotic genomes are generally organized in multiple chromosomes. Here we have created a functional single-chromosome yeast from a Saccharomyces cerevisiae haploid cell containing sixteen linear chromosomes, by successive end-to-end chromosome fusions and centromere deletions. The fusion of sixteen native linear chromosomes into a single chromosome results in marked changes to the global three-dimensional structure of the chromosome due to the loss of all centromere-associated inter-chromosomal interactions, most telomere-associated inter-chromosomal interactions and 67.4% of intra-chromosomal interactions. However, the single-chromosome and wild-type yeast cells have nearly identical transcriptome and similar phenome profiles. The giant single chromosome can support cell life, although this strain shows reduced growth across environments, competitiveness, gamete production and viability. This synthetic biology study demonstrates an approach to exploration of eukaryote evolution with respect to chromosome structure and function. Successive fusion of yeast chromosomes is used to produce a single-chromosome strain that is viable, albeit with slightly reduced fitness. [ABSTRACT FROM AUTHOR]

Functional organic-inorganic nanocomposites with high transparency show significant potential application in many fields. However, it is still a great challenge to prepare flexible transparent nanocomposites due to the intrinsic stiffness of the nanoparticles and the poor interaction between nanoparticles and organic matrices. In this work, a transparent ternary nanocomposite film with enhanced mechanical performance is fabricated by two-steps. First, the transparent ternary ZnO/MWCNTs/ n-butyl methacrylate (BMA) nanodispersion is prepared by mixing the ZnO/BMA and MWCNTs/BMA dispersions directly. Then, the ternary nanocoposites film is fabricated via in-situ bulk polymerization of the above nanodispersions. As a result, the tensile strength of the ZnO/MWCNTs/poly- n-butyl methacrylate (PBMA) ternary film is enhanced by 42% and the elongation at break is three times that of ZnO/PBMA nanocomposite. The hardness of the film increases from 5B to 1H with 40 wt% ZnO. These results indicate that ZnO and MWCNTs can improve the mechanical properties of the composite significantly. Importantly, the ternary nanocomposite film still remains high transparency and exhibit excellent UV-shielding performance. The as-prepared transparent multifunctional nanocomposite films have promising applications in optical materials and devices, such as optical filters, contact lenses and protection packing. [ABSTRACT FROM AUTHOR]

Key message: Six MnSOD genes were isolated from five Miscanthus species. MgMnSOD1 functions in mitochondria and MgMnSOD1 seems to be the main MnSOD gene involved in stress response of M. × giganteus. Abstract: Miscanthus × giganteus is a promising biomass energy crop with advantages of vigorous growth, high yield, low fertilizer and pesticide inputs. However, poor overwinter ability limits its widespread cultivation. Moreover, narrow genetic base may increase the risk of susceptibility to diseases and pests. Manganese superoxide dismutase (MnSOD), an important antioxidant enzyme involved in stress tolerance is able to protect plant cells from accumulated reactive oxygen species by converting superoxide to peroxide and oxygen. In many plants, overexpression of MnSOD has shown the ability to enhance the resistance to various stresses. This article describes the studies performed in an attempt to elucidate the molecular and enzymatic properties of MnSODs in M. × giganteus. MnSOD genes from M. × giganteus ( MgMnSOD1, MgMnSOD2), M. lutarioriparia ( MlMnSOD), M. sacchariflora ( MsaMnSOD), M. sinensis ( MsiMnSOD), and M. floridulus ( MfMnSOD) were cloned and sequenced. The sequence analysis and expression patterns of MgMnSOD1 and MgMnSOD2 suggest that they were orthologous genes which were inherited from the two parents, M. sacchariflora and M. sinensis, respectively. In addition, MgMnSOD1 is predicted to be the main MnSOD gene involved in stress response of M. × giganteus. The activity of purified recombinant MgMnSOD1 was 1854.79 ± 39.98 U mg (mean ± SD). Further enzymatic assays revealed that the protein exhibited an outstanding thermal stability. MgMnSOD1 is predicted to be targeted to mitochondria and involved in removing the superoxide radical generated by respiration. The presence and sequences of other SOD isozymes transcripts were also investigated in this study. [ABSTRACT FROM AUTHOR]