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A new metal-free xanthene-bridged bis-corrole had been synthesized and used as a catalyst for electrocatalytic hydrogen evolution reaction for the first time. This bis-corrole demonstrated high catalytic efficiency in DMF and acetonitrile-aqueous solution upon using acetic acid as the protons source. The turnover frequency (TOF) could reach 627.75 h–1 in DMF at the overpotential of 924 mV and 581.42 h–1 in neutral buffer acetonitrile-aqueous solution at the overpotential of 828 mV. The prepared bis-corrole also exhibted good stability in the electrolysis. This study highlights that linking one corrole macrocycle to another can lead to the metal-free bis-corrole as a stable HER catalyst. [ABSTRACT FROM AUTHOR]

As special maize with more than 6% oil concentration in the grain, high-oil maize has received increased interest recently. To date, little is known about the expressions of genes involved in fatty acid metabolism of high-oil maize. Stearoyl-acyl carrier protein desaturase (SAD) is a key enzyme that converts stearic acid to oleic acid. In this study, two-dimensional electrophoresis, gas chromatography, and real-time PCR were used to determine the expressions of SAD at three seed development stages in high-oil and normal maize inbred lines. SAD was significantly more abundantly expressed in high-oil maize than in normal maize, not only at the protein and mRNA levels, but also at the product level. These results suggested that a high expression of SAD may play an important role in increasing oil concentration in high-oil maize. [ABSTRACT FROM AUTHOR]

The effects of NaCl stress on the activity of antioxidant enzymes, lipid peroxidation, cell membrane stability, net photosynthetic rate, gas-exchange, and chlorophyll content were investigated in two Jerusalem artichoke cultivars, Dafeng (salt-tolerant) and Wuxi (salt-sensitive), grown under control (nutrient solution) or salt stress (nutrient solution containing 75, 150, and 225 mM NaCl) conditions for 7 days. In leaves of salt-tolerant cv. Dafeng, superoxide dismutase (EC 1.15.1.1), peroxidase (EC 1.11.1.7), and catalase (EC 1.11.1.6) activities significantly increased as compared to the controls, whereas no significant change was observed in cv. Wuxi. Lipid peroxidation and cell membrane injury were enhanced in both cultivars. Net photosynthesis and stomatal conductance decreased in response to salt stress, but cv. Dafeng showed a smaller reduction in photosynthesis than cv. Wuxi. The results indicated that stomatal aperture limited leaf photosynthetic capacity in the NaCl-treated plants of both cultivars. However, significant reduction in the leaf chlorophyll content due to NaCl stress was observed only in cv. Wuxi. These results suggested that salt-tolerant Jerusalem artichoke varieties may have a better protection against reactive oxygen species, at least in part, by increasing the activity of antioxidant enzymes under salt stress. [ABSTRACT FROM AUTHOR]

Quasi-static tests in bending of thin-walled beams with different material design forms and weak link locations have been carried out, and their deformation mode and force responses are investigated by numerical simulations. The influence of some factors, including fiber direction, stacking sequence, and making holes in different positions, on the energy absorption of thin-walled CFRP beams is analyzed. [ABSTRACT FROM AUTHOR]

The process of coal mining generates high amounts of coal gangue. Accordingly, coal–gangue separation is a key problem limiting coal production and quality. Terahertz time-domain spectroscopy was combined with multivariate statistical analyses to identify different kinds of coal and gangue. First, the terahertz spectrum and power spectrum of the sample were measured, and the refractive index and absorption coefficient of the sample were calculated from the terahertz time-domain spectrum of the sample. Significant differences in the power spectrum, refractive index, and absorption coefficient were found between different kinds of coal and gangue. After combining multivariate statistical methods — cluster analysis (CA) and principal component analysis (PCA) — a model based on THz parameters and different types of coal and gangue was established. During cluster analysis, the Euclidean distance of two types of samples and the score of the first principal component in the principal component analysis could reflect the similarity and dissimilarity between coal and gangue samples, and consistent results were obtained for CA and PCA. The experimental results showed that the combination of terahertz technology and multivariate statistical methods yielded an accurate approach to distinguishing between coal and gangue. [ABSTRACT FROM AUTHOR]

A correction to the article "Antioxidant enzymes and physiological characteristics in two Jerusalem artichoke cultivars under salt stress" that was published in a previous issue of the periodical is presented.

The enthalpies of dilution, Δdil Hm, have been measured for LiCl+Li2B4O7+H2O system at T=298.15 K by using a RD496-III microcalorimeter. A suitable measurement method was used to obtain the better data of the enthalpies of dilution for the ternary mixing solutions to low concentrations. The relative apparent molar enthalpies, Lϕ, have been determined and the relationships between Lϕ and ionic strength I at different molal fractions of Li2B4O7 were obtained. The effect of the borate Li2B4O7 on the heat properties for the studied system was discussed. [ABSTRACT FROM AUTHOR]

In the present research, the phase distribution of the detonation products of emulsion explosives used to prepare nano-MnFeO powders by detonation is simulated by a numerical method. The mechanism of nano-MnFeO powder synthesis via detonation of emulsion explosives is discussed and explained. The results obtained indicate that FeO and MnO form in the reaction zone before the Chapman-Jouguet detonation state is reached; these oxides react with surplus oxygen in air during the decrease in temperature and pressure, resulting in MnFeO generation. [ABSTRACT FROM AUTHOR]

The chrysanthemum ( Dendranthema morifolium) variety 'Yuhuajinhua' has a creeping growth habit. An ELISA-based assessment of the content and distribution of IAA in the stem of 'Yuhuajinhua' showed that there was an IAA concentration gradient across the stem segment between the 2nd and 4th nodes, counting from the apex, before the creeping growth, while this difference disappeared after the initiation of creeping growth. An immunohistochemical assay for IAA showed that auxin was concentrated in the epidermis and cortex of the proximal side of the stem, particularly in the first few hours after gravitational stimulation was applied. The bending of the stem was generated by the asymmetric elongation of the epidermal cells in proximal side of the stem, especially upon to 6 h after gravistimulation, and this was probably mediated by an alteration in the IAA gradient across the stem. Exogenously applied 1-naphthaleneacetic acid (NAA) or 2,3,5-triiodobenzoic acid (TIBA) played converse effects on the gravitropic stem curvature. The data support the idea that IAA plays a crucial regulatory role in the formation of the creeping habit in the chrysanthemum variety 'Yuhuajinhua'. [ABSTRACT FROM AUTHOR]

ABA addition to B5 or M9 medium at the concentrations from 0.1 to 5.0 mg/l suppressed growth of Onosma paniculatum cells. The addition of these ABA concentrations to M9 medium also significantly decreased the formation of shikonin and its derivatives in the cultured cells during the entire course of culturing. The enzyme activity assay showed that, on the 4th day after inoculation, 0.1 mg/l ABA significantly decreased the activities of phenylalanine ammonia-lyase, the first enzyme, and p-hydroxybenzoic acid-geranyltransferase, a key enzyme involved in shikonin biosynthesis. However, no significant change in these two enzyme activities was found during the following days for testing (8, 12, and 16 days). Interestingly, RT-PCR analysis of the PAL1 and LePGT1 gene expression showed no significant changes on the 4th day after inoculation. Furthermore, we found that the inhibitory effect of ABA on the secondary metabolism could be alleviated significantly by the addition of 2-aminoethyl diphenyl borate (an inhibitor of inositol triphosphate-receptor) or nicotinamide (an inhibitor of ADP-ribose cyclase), which functions by decreasing the intracellular calcium concentration. [ABSTRACT FROM AUTHOR]

The crystal and molecular structures of the [PrIII(nta)(H2O)2]$\backslash cdot$H2O (nta = nitrilotriacetic acids), K3[GdIII(nta)2(H2O)]$\backslash cdot$6H2O, and K3[YbIII(nta)2]$\backslash cdot$5H2O complexes have been determined by single-crystal X-ray structure analyses. In [PrIII(nta)(H2O)2]$\backslash cdot$H2O, the PrIIINO8 part forms a nine-coordinate pseudo-monocapped square antiprismatic structure in which one N and three O atoms are from one nta ligand in the same molecule, three O atoms from another nta ligand in the neighboring molecule and two O atoms from two coordinate water molecules. In K3[GdIII(nta)2(H2O)]$\backslash cdot$6H2O, the [GdIII(nta)2(H2O)$]^\{3-\}$ complex anion has a nine-coordinate pseudo-monocapped square antiprismatic structure in which each nta acts as a tetradentate ligand with one N atom of the amino group and three O atoms of the carboxylic groups. In K3[YbIII(nta)2]$\backslash cdot$5H2O, each nta also acts as a tetradentate ligand with one N atom of amino group and three O atoms of the carboxylic groups, but the [YbIII(nta)2$]^\{3-\}$ complex anion has an eight-coordinate structure with a distorted square antiprismatic prism. All the results including those for [TmIII(nta)(H2O)2]$\backslash cdot$2H2O confirm the inferences on the coordinate structures and coordination numbers of rare earth metal complexes with the nta ligand. [ABSTRACT FROM AUTHOR]

We report a 52-year-old female patient with a 2-year history of local neck pain, decreased cervical spine rotation, progressive numbness and weakness of both arms. Preoperative, dynamic X-rays, computed tomography, three-dimensional computed tomography demonstrated a displaced Os odontoideum with irreducible Subluxation of C1/2. We used a single transoral approach release, reduction using an assistance of skull traction, bone fusion and stabilization in the treatment of Os odontoideum with irreducible alantoaxial dislocation. Postoperative, the patient was free of all symptoms and X-rays taken showed a stable fusion of C1/2 at 6th postoperative month. This technique in the treatment of Os odontoideum with irreducible alantoaxial dislocation is atraumatic and effective. And preoperative dynamic X-rays, computed tomography, three-dimensional computed tomography and MRI scans provided an invaluable aid to select this operative procedure. [ABSTRACT FROM AUTHOR]