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By using solar energy as the power source, aligned and clean reclaimed carbon fibers (RCFs) were successfully recovered from carbon fiber-reinforced polymer (CFRP). Furthermore, α-MnO 2 nanowires were grown on the RCF surface through a one-step hydrothermal process, and thus MnO 2 /RCF composite was successfully prepared. Both the RCF and MnO 2 /RCF can be directly utilized as supercapacitor electrode, and the electrochemical performance of the electrode materials were evaluated by utilizing cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), and electrochemical impedance spectroscopy (EIS) in a three-electrode cell. RCF electrode exhibited a favorable performance with a prolonged potential window (−1.6–0 V) in a 2 mol L −1 of aqueous KOH solution, while the MnO 2 /RCF electrode prepared at 150 °C showed a superior electrochemical performance in a 1 mol L −1 of aqueous Na 2 SO 4 solution: a specific capacitance of 228.8 F g −1 at 1 A g −1 and high cycling stability (about 91.2% capacitance retention after 3000 cycles). A MnO 2 /RCF-based asymmetric supercapacitor was assembled, which exhibited excellent performances with a voltage window of 2.0 V, a high energy density of 22.9 Wh kg −1 and a remarkable cycling stability (89% capacitance retained after 1000 cycles at 2.25 A g −1 ). [ABSTRACT FROM AUTHOR]

Clean, undamaged carbon fibers were easily separated from thermoset epoxy-based carbon fiber reinforced polymers through a two-step solvothermal method by using propanol or benzyl alcohol as solvents. The recovered carbon fibers were characterized by thermal gravity analysis, Fourier transform infrared spectroscopy, scanning electron microscopy, and mechanical tensile strength tests together with the digital photos. Results show that solvothermal temperature and duration, as well as pretreatment in dichloromethane play important roles in recovering carbon fiber. In addition, the tensile strength of the recovered carbon fibers remains approximately 94.5–98% of virgin carbon fibers. [ABSTRACT FROM AUTHOR]

Aligned reclaimed carbon fiber (RCF) was reused as a conductive support to load hierarchical molybdenum disulfide (MoS 2 ) spheres and thus MoS 2 /RCF composite was constructed. The synthesis of MoS 2 and its loading were simultaneously completed during a facile hydrothermal process. This MoS 2 /RCF was directly utilized as the negative electrode for supercapacitor without any further process, which exhibited superior electrochemical performance: A specific capacitance of 225 F g −1 at 0.5 A g −1 . Furthermore, an asymmetric supercapacitor (ASC) was assembled by coupling this MoS 2 /RCF electrode (−) with MnO 2 /RCF electrode (+), which delivered an energy density of 22.5 W h kg −1 at a power density of 703 W kg −1 over a wide potential range of 1.7 V. This RCF may be a promising conductive support candidate for those electrodes in the energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D porous CuS/carbon octahedron was prepared by in-situ sulfidation of Cu-MOF. • As-prepared materials can provide excellent conductivity and numerous active sites. • The sensor displayed enhanced electrochemical activity for sensing of AA. • Constructed sensor exhibited low detection limit, good reproducibility and stability. • This method could put into use for the drug monitoring and clinical diagnosis. Sensitive and reliable detection of the antioxidant ascorbic acid (AA) is crucial for biosensing and food safety applications. Herein, CuS/carbon composites (CuS@C-c) with porous octahedral structure were successfully fabricated by pre-carbonization and then sulfidation of the precursor Cu-MOF templates, which allowed for the in-situ encapsulation of CuS into the carbon matrix, simultaneously endowing the CuS@C-c with high conductivity and rigid structure protection. Benefiting from the unique structural features, the CuS@C-c displayed significantly improved electrochemical performance compared with hydrothermal disordered structural products (CuS@C-h). The CuS@C-c was employed for preparing the modified electrode and exhibited distinguished electrocatalytic oxidation of AA with a wide linear range of 0.1–1000.0 μmol/L and a low detection limit of 0.03 μmol/L, which could be attributed to synergistic contributions of CuS and carbon matrix, as well as their unique 3D open porous structure, which provided abundant accessible active sites and accelerating electron transfer. The developed electrode showed good anti-interference ability, long-term stability, and reproducibility and was able to efficiently detected AA contents in pharmaceuticals and human urine samples with acceptable recoveries. [ABSTRACT FROM AUTHOR]

Summary: Triterpenes are thirty‐carbon compounds derived from the universal five‐carbon prenyl precursors isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Normally, triterpenes are synthesized via the mevalonate (MVA) pathway operating in the cytoplasm of eukaryotes where DMAPP is condensed with two IPPs to yield farnesyl diphosphate (FPP), catalyzed by FPP synthase (FPS). Squalene synthase (SQS) condenses two molecules of FPP to generate the symmetrical product squalene, the first committed precursor to sterols and most other triterpenes. In the green algae Botryococcus braunii, two FPP molecules can also be condensed in an asymmetric manner yielding the more highly branched triterpene, botryococcene. Botryococcene is an attractive molecule because of its potential as a biofuel and petrochemical feedstock. Because B. braunii, the only native host for botryococcene biosynthesis, is difficult to grow, there have been efforts to move botryococcene biosynthesis into organisms more amenable to large‐scale production. Here, we report the genetic engineering of the model monocot, Brachypodium distachyon, for botryococcene biosynthesis and accumulation. A subcellular targeting strategy was used, directing the enzymes (botryococcene synthase [BS] and FPS) to either the cytosol or the plastid. High titres of botryococcene (>1 mg/g FW in T0 mature plants) were obtained using the cytosolic‐targeting strategy. Plastid‐targeted BS + FPS lines accumulated botryococcene (albeit in lesser amounts than the cytosolic BS + FPS lines), but they showed a detrimental phenotype dependent on plastid‐targeted FPS, and could not proliferate and survive to set seed under phototrophic conditions. These results highlight intriguing differences in isoprenoid metabolism between dicots and monocots. [ABSTRACT FROM AUTHOR]

The phenylpropanoid biosynthetic pathway that generates lignin subunits represents a significant target for altering the abundance and composition of lignin. The global regulators of phenylpropanoid metabolism may include MYB transcription factors, whose expression levels have been correlated with changes in secondary cell wall composition and the levels of several other aromatic compounds, including anthocyanins and flavonoids. While transcription factors correlated with downregulation of the phenylpropanoid biosynthesis pathway have been identified in several grass species, few transcription factors linked to activation of this pathway have been identified in C4 grasses, some of which are being developed as dedicated bioenergy feedstocks. In this study we investigated the role of SbMyb60 in lignin biosynthesis in sorghum ( Sorghum bicolor), which is a drought-tolerant, high-yielding biomass crop. Ectopic expression of this transcription factor in sorghum was associated with higher expression levels of genes involved in monolignol biosynthesis, and led to higher abundances of syringyl lignin, significant compositional changes to the lignin polymer and increased lignin concentration in biomass. Moreover, transgenic plants constitutively overexpressing SbMyb60 also displayed ectopic lignification in leaf midribs and elevated concentrations of soluble phenolic compounds in biomass. Results indicate that overexpression of SbMyb60 is associated with activation of monolignol biosynthesis in sorghum. SbMyb60 represents a target for modification of plant cell wall composition, with the potential to improve biomass for renewable uses. [ABSTRACT FROM AUTHOR]

Background and Aims During seed fill in cereals, nutrients are symplasmically unloaded to vascular parenchyma in ovules, but thereafter nutrient transport is less certain. In Zea mays, two mechanisms of nutrient passage through the chalaza and nucellus have been hypothesized, apoplasmic and symplasmic. In a recent study, nutrients first passed non-selectively to the chalazal apoplasm and were then selectively absorbed by the nucellus before being released to the endosperm apoplasm. This study reports that the promoter of OUTER CELL LAYER3 (PSbOCL3) from Sorghum bicolor (sorghum) directs gene expression to chalazal cells where the apoplasmic barrier is thought to form. The aims were to elucidate PSbOCL3 expression patterns in sorghum and relate them to processes of nutrient pathway development in kernels and to recognized functions of the homeodomain-leucine zipper (HD-Zip) IV transcription factor family to which the promoter belongs. Methods PSbOCL3 was cloned and transformed into sorghum as a promoter–GUS (β-glucuronidase) construct. Plant tissues from control and transformed plants were then stained for GUS, and kernels were cleared and characterized using differential interference contrast microscopy. Key Results A symplasmic disconnect between the chalaza and nucellus during seed fill is inferred by the combination of two phenomena: differentiation of a distinct nucellar epidermis adjacent to the chalaza, and lysis of GUS-stained chalazal cells immediately proximal to the nucellar epidermis. Compression of the GUS-stained chalazal cells during kernel maturation produced the kernel abscission zone (closing layer). Conclusions The results suggest that the HD-Zip IV transcription factor SbOCL3 regulates kernel nutrition and abscission. The latter is consistent with evidence that members of this transcription factor group regulate silique abscission and dehiscence in Arabidopsis thaliana. Collectively, the findings suggest that processes of floral organ abscission are conserved among angiosperms and may in some respects differ from processes of leaf abscission. [ABSTRACT FROM AUTHOR]

Sorghum prolamins, termed kafirins, are categorized into subgroups α, β, and γ. The kafirins are co-translationally translocated to the endoplasmic reticulum (ER) where they are assembled into discrete protein bodies that tend to be poorly digestible with low functionality in food and feed applications. As a means to address the issues surrounding functionality and digestibility in sorghum, we employed a biotechnology approach that is designed to alter protein body structure, with the concomitant synthesis of a co-protein in the endosperm fraction of the grain. Wherein perturbation of protein body architecture may provide a route to impact digestibility by reducing disulphide bonds about the periphery of the body, while synthesis of a co-protein, with known functionality attributes, theoretically could impact structure of the protein body through direct association and/or augment end-use applications of sorghum flour by stabilizing ß-sheet formation of the kafirins in sorghum dough preparations. This in turn may improve viscoelasticity of sorghum dough. To this end, we report here on the molecular and phenotypic characterizations of transgenic sorghum events that are down-regulated in γ- and the 29-kDa α-kafirins and the expression of a wheat Dy10/Dx 5 hybrid high-molecular weight glutenin protein. The results demonstrate that down-regulation of γ-kafirin alone does not alter protein body formation or impacts protein digestibility of cooked flour samples. However, reduction in accumulation of a predicted 29-kDa α-kafirin alters the morphology of protein body and enhances protein digestibility in both raw and cooked samples. [ABSTRACT FROM AUTHOR]