Relationships between base-catalyzed hydrolysis rates or glutathione reactivity for acrylates and methacrylates and their NMR spectra or heat of formation

The NMR chemical shift, i.e., the π-electron density of the double bond, of acrylates and methacrylates is related to the reactivity of their monomers. We investigated quantitative structure-property relationships (QSPRs) between the base-catalyzed hydrolysis rate constants (k1) or the rate constant with glutathione (GSH) (log k(GSH)) for acrylates and methacrylates and the (13)C NMR chemical shifts of their α,β-unsaturated carbonyl groups (δC(α) and δC(β)) or heat of formation (Hf) calculated by the semi-empirical MO method. Reported data for the independent variables were employed. A significant linear relationship between k1 and δC(β), but not δC(α), was obtained for methacrylates (r(2) = 0.93), but not for acrylates. Also, a significant relationship between k1 and Hf was obtained for both acrylates and methacrylates (r(2) = 0.89). By contrast, log k(GSH) for acrylates and methacrylates was linearly related to their δC(β) (r(2) = 0.99), but not to Hf. These findings indicate that the (13)C NMR chemical shifts and calculated Hf values for acrylates and methacrylates could be valuable for estimating the hydrolysis rate constants and GSH reactivity of these compounds. Also, these data for monomers may be an important tool for examining mechanisms of reactivity.     

Stabilization of flavylium dye by incorporation into the pore of protonated zeolites

Flavylium dye, a model compound of natural anthocyanin, has a defect that its color stability is very poor. We have complexed the flavylium dye with protonated zeolites and succeeded to enhance both the thermal and chemical stability of the dye. The aqueous dispersion of the flavylium/zeolite complex maintains its color even at 353 K or at pH 9, under which conditions the aqueous solution of the flavylium loses its color immediately. The stability is enhanced when the dye is incorporated into the pore of the zeolites, and a large stabilization effect is obtained by a tight adsorption with a narrow pore, as long as the dye is incorporated into the pore. Because of its enhanced color stability, the flavylium dye incorporated in the zeolite pore can be a candidate for an environmentally friendly coloring material.     

Effect of REM addition of wire on CO2 gas shielded arc phenomenon

Carbon dioxide (CO₂) gas shielded arc welding is the main arc welding method, but it generates a large amount of spatter during welding. The root cause of spatter lies in the fact that the droplet undergoes repeated irregular shaking. To solve this problem, spatter generation modes were clarified and the effects of polarity and rare earth metal (REM) addition of the wire on CO₂ gas shielded arc welding were investigated. As a result, when welding is performed with an electrode negative (DCEN) polarity using REM added wire, it was found that a conical arc plasma is formed, and the droplet which is transferred from the wire tip to the molten pool is fine and continuous, in what is termed ‘spray transfer’. Thus, spatter generation was reduced to 10% of amount of the conventional CO₂ gas shielded arc welding (from 0.058 to 0.005g/s).     

Phase relationship on Mo-S system at high temperatures

Changing the partial pressure of sulfur Ps₂ at temperatures of 750° and 950°C, phase equilibria on the Mo-S system by solid-gas reaction were investigated. Hexagonal 2H-MoS₂ and monoclinic Mo₂S₃ phases were identified from the x-ray powder diffraction pattern. The 2H-MoS₂ had a slight homogeneity range, i.e. MoS_1.978 to MoS_2.0 at 950°C, MoS_1.983 to MoS_2.0 at 750°C. No remarkable variation of lattice parameters for the MoS₂ was observed. The composition of the Mo₂S₃ phase was not stoichiometric MoS_1.5 but MoS_1.457 at 950°C. At 750°C the composition of the Mo₂S₃ phase could not be determined since it was quite difficult to establish the equilibrium state between the gas and the condensed phases. This finding agreed well with the result of Morimoto and Kullerud.     

A new approach to species determination for yeast strains: DNA microarray-based comparative genomic hybridization using a yeast DNA microarray with 6000 genes

DNA-DNA hybridization is known as the superior method in the elucidation of relationships between closely related taxa, such as species and strain. For species determination we propose a new DNA-DNA hybridization method: the DNA microarray-based comparative genomic hybridization (CGH) method, using a yeast DNA microarray with approximately 6000 genes. The genome from a yeast strain as a sample strain (Sample) was labelled with Cy3-dye and hybridized to a single DNA microarray, together with the Cy5-labelled genome of S. cerevisiae S288C as a reference strain (Reference). The log2 ratio values [log2[Cy3(Sample)/Cy5(Reference)]: Ratio] of signal intensities of all the gene spots were estimated and divided into the following groups: Ratio < or = -1; -1 < Ratio < 1; 1 < or = Ratio. The hybridization profiles of the genomes of type strains belonging to the genus Saccharomyces were significantly different from that of S. cerevisiae S288C. The Ratio-based grouping allowed us to discriminate between some species from S. cerevisiae more clearly. Furthermore, cluster analysis discriminated between closely related species and strains. Using this method, we were able to not only perform species determination but also to obtain information on alternation in gene copy number of such gene amplifications and deletions with single-gene resolution. These observations indicated that DNA microarray-based CGH is a powerful system for species determination and comparative genome analysis.     

Purification and characterization of an extracellular beta-agarase from Bacillus sp. MK03

A new beta-agarase was purified from an agarolytic bacterium, Bacillus sp. MK03. The enzyme was purified 129-fold from the culture supernatant by ammonium sulfate precipitation, anion exchange and gel filtration column chromatographic methods. The purified enzyme appeared as a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Estimation of the molecular mass by SDS-PAGE and gel filtration gave values of 92 kDa and 113 kDa, respectively. The N-terminal amino acid sequence of the enzyme showed no homology to those of other known agarases. The optimum pH and temperature for this enzyme were 7.6 and 40 degrees C, respectively. The predominant hydrolysis product of agarose by this enzyme was neoagarotetraose, indicating the cleavage of beta-1,4 linkage. This enzyme could hydrolyze neoagarohexaose to produce neoagarotetraose and neoagarobiose; it could not hydrolyze these products. The enzyme digested agarose by endo-type hydrolysis.     

Informative patches sampling for image classification by utilizing bottom-up and top-down information

In image classification based on bag of visual words framework, image patches used for creating image representations affect the classification performance significantly. However, currently, patches are sampled mainly based on processing low-level image information or just extracted regularly or randomly. These methods are not effective, because patches extracted through these approaches are not necessarily discriminative for image categorization. In this paper, we propose to utilize both bottom-up information through processing low-level image information and top-down information through exploring statistical properties of training image grids to extract image patches. In the proposed work, an input image is divided into regular grids, each of which is evaluated based on its bottom-up information and/or top-down information. Subsequently, every grid is assigned a saliency value based on its evaluation result, so that a saliency map can be created for the image. Finally, patch sampling from the input image is performed on the basis of the obtained saliency map. Furthermore, we propose a method to fuse these two kinds of information. The proposed methods are evaluated on both object categories and scene categories. Experiment results demonstrate their effectiveness.     

Effect of transition elements on the properties of MC carbides in IN-100 nickel-based superalloy

The effect of nine transition elements on the morphology, distribution and composition of MC carbides (MCs) in a nickel-base superalloy, IN-100, was investigated by differential thermal analysis (DTA), microstructural observation and X-ray microanalysis. The doping with tantalum, tungsten and molybdenum caused a significant change in the morphology and distribution of MCs as well as the profile of DTA curve of IN-100. The compositions of the MC in IN-100 were TiC and (Ti_0.80Mo_0.17V_0.03) C, and the doping with niobium, tantalum and tungsten changed significantly the composition of MC. On the other hand, the doping with chromium, vanadium, hafnium and zirconium scarcely changed the composition. In addition to TiC and (Ti, Mo, V) C, zirconium- and hafnium-rich MCs were found in the zirconium- and hafnium-doped alloys, respectively. The effect of the dopants on the composition of MCs could be explained by a relationship between the metallic radius and the free energy of formation for the MC.     

Development of the Water Cooled Ceramic Breeder Test Blanket Module in Japan

The development of a Water Cooled Ceramic Breeder (WCCB) Test Blanket Module (TBM) is being performed as one of the most important steps toward DEMO blanket in Japan. For the TBM testing and evaluation toward DEMO blanket, the module fabrication technology development by a candidate structural material, reduced activation martensitic/ferritic steel, F82H, is one of the most critical items from the viewpoint of realization of TBM testing in ITER. In Japan, fabrication of a real scale first wall, side walls, a breeder pebble bed box and assembling of the first wall and side walls have succeeded. Recently, the real scale partial mockup of the back wall was fabricated. The fabrication procedure of the back wall, whose thickness is up to 90 mm, was confirmed toward the fabrication of the real scale back wall by F82H. Important key technologies are almost clarified for the fabrication of the real scale TBM module mockup. From the view point of testing and evaluation, development of the technology of the blanket tritium recovery, development of advanced breeder and multiplier pebbles and the development of the blanket neutronics measurement technology are also performed. Also, tritium production and recovery test using D-T neutron in the Fusion Neutronics Source (FNS) facility has been started as the verification test of tritium production performance. This paper overviews the recent achievements of the development of the WCCB TBM in Japan.     

Constitutive Effects of Lead on Aryl Hydrocarbon Receptor Gene Battery and Protection by β‐carotene and Ascorbic Acid in Human HepG2 Cells

Lead (Pb) is an environmental pollutant that can get entry into human body through contaminated foods, drinks, and inhaled air leading to severe biological consequences, and has been responsible for many deaths worldwide. The objectives of this study were 1st to investigate the modulatory effects of environmentally relevant concentrations of Pb on AhR gene battery, which is controlling xenobiotics metabolism. 2nd, trials to reduce Pb‐induced adverse effects were done using some phytochemicals like β‐carotene or ascorbic acid. Human hepatoma (HepG2) cell lines were exposed to a wide range of Pb concentrations varying from physiological to toxic levels (0 to 10 mg/L) for 24 h. High Pb concentrations (1 to 10 mg/L) significantly reduced phase I (CYP1A1 and 1A2) and phase II (UGT1A6 and NQO1) xenobiotic metabolizing enzyme mRNA expression in a mechanistic manner through the AhR regulation pathway. Additionally, these Pb concentrations induced oxidative stress in HepG2 cells in terms of production of reactive oxygen species (ROS) and induced heme oxygenase‐1 mRNA expression in a concentration‐dependent phenomenon. Coexposure of HepG2 cells to physiological concentrations of some micronutrients, like β‐carotene (10 μM) or ascorbic acid (0.1 mM), along with Pb (1 mg/L) for 24 h significantly reduced the levels of ROS production and recovered AhR mRNA expression into the normal levels. Thus, consumption of foods rich in these micronutrients may help to reduce the adverse effects of lead in areas with high levels of pollution.