Identification of enzyme responsible for erythritol utilization and reaction product in yeast Lipomyces starkeyi

We have identified the enzyme responsible for erythritol utilization and its reaction product in the yeast Lipomyces starkeyi CBS 1807. The enzyme, a polyol dehydrogenase requiring NAD+ as a coenzyme, was induced by erythritol in this yeast. We confirmed that the enzyme product was L-erythrulose by MS, NMR, and polarimeter analyses, meaning that we clarified the first step of erythritol utilization in yeasts for the first time. In the case of the oxidative reaction, D-threitol, (2R,3R)-2,3-butanediol, and erythritol were much better substrates than 21 other polyols tested. These three substrates are tetroses and have an R configuration at C-3, and whose third carbon results in easiest oxidation in this enzyme. The research of the substrate specificity in the reductive reaction demonstrated that L-erythrulose and dihydroxyacetone were better substrates, that D-acetoin was inactive and L-erythrose (aldose) was slightly active.     

Thermoelectric properties of ternary and Al-containing quaternary Ru1−xRexSiy chimney–ladder compounds

The thermoelectric properties of ternary and Al-containing quaternary Ru_1?xRe_xSi_y chimney–ladder phases have been studied as a function of the Re concentration with the use of directionally solidified alloys. The Ru_1?xRe_xSi_y chimney–ladder phases exhibit n- and p-type semiconducting behaviors, respectively, at low and high Re concentrations, at which the X(=Si)/M(=Ru + Re) ratios are respectively, larger and smaller than those expected from the VEC (valence electron concentration) = 14 rule. The absolute values of both Seebeck coefficient and electrical resistivity increase as the extent of the deviation from the VEC = 14 rule increases, i.e. as the alloy composition deviates from that corresponding to the p–n transition (x ≈ 0.5), indicating that the carrier concentration can be controlled by changing the extent of compositional deviation from the ideal VEC = 14 composition. The highest values of the dimensionless figure of merit obtained are 0.47 for ternary (x = 0.60) and 0.56 for Al-containing quaternary alloys. The reasons for the systematic compositional deviation from the ideal VEC = 14 compositions observed for a series of chimney–ladder phases are discussed in terms of atomic packing.     

Equilibrium state and crystal growth of (BEDT-TTF)2I3

The equilibrium state and crystal growth of (BEDT-TTF)₂I₃ were investigated. Measurements of the temperature dependence of solubility and analyses of the components in the solution were carried out. The analysis of the solution showed that the crystals decompose into neutral BEDT-TTF and I₂ molecules. As to the polymorphism, it was clarified that the -form is more stable than the -form in the temperature region between 0 and 50 °C. Using these information, we succeed in growing single crystals form BEDT-TTF and I₂ and in control of the crystallizing polymorph. The polymorphic behavior was explained in terms of supersaturation as a driving force of crystal growth.     

Identification of sewer pipes to be cleaned for reduction of CSO pollutant load.

To reduce the CSO (Combined Sewer Overflow) pollutant discharge, one of the effective options is cleaning of sewer pipes before rainfall events. To maximize the efficiency, identification of pipes to be cleaned is necessary. In this study, we discussed the location of pipe deposit in dry weather in a combined sewer system using a distributed model and investigated the effect of pipe cleaning to reduce the pollutant load from the CSO. First we simulated the dry weather flow in a combined sewer system. The pipe deposit distribution in the network was estimated after 3 days of dry weather period. Several specific pipes with structural defect and upper end pipes tend to have an accumulation of deposit. Wet weather simulations were conducted with and without pipe cleaning in rainfall events with different patterns. The SS loads in CSO with and without the pipe cleaning were compared. The difference in the estimated loads was interpreted as the contribution of wash-off in the cleaned pipe. The effect of pipe cleaning on reduction of the CSO pollutant load was quantitatively evaluated (e.g. the cleaning of one specific pipe could reduce 22% of total CSO load). The CSO simulations containing pipe cleaning options revealed that identification of pipes with accumulated deposit using the distributed model is very useful and informative to evaluate the applicability of pipe cleaning option for CSO pollutant reduction.     

Splitting of guest atom sites and lattice thermal conductivity of type-I and type-III clathrate compounds in the Ba–Ga–Ge system

The crystal structures of type-I and type-III clathrate compounds in the Ba–Ga–Ge system have been investigated by synchrotron X-ray powder diffraction at room temperature with single- and split-site models to describe thermal vibration of the Ba atoms that are believed to ‘rattle’ in the encapsulating cages. The split-site model is verified to be more plausible when judged from the changes of the extent of thermal vibration of the Ba atoms and the shape changes of the encapsulating cages with the Ga content for both types of compound. When described with the split-site model, the value of lattice thermal conductivity at room temperature decreases with increasing split distance of the Ba atom site for both types of compound, indicating that the split distance can be used as a parameter to describe the extent of thermal vibration (rattling motion) of the Ba guest atoms in the encapsulating cages.     

Wavelet-Texture Method: Appearance Compression by Polarization, Parametric Reflection Model, and Daubechies Wavelet

In order to create a photorealistic Virtual Reality model, we have to record the appearance of the object from different directions under different illuminations. In this paper, we propose a method that renders photorealistic images from a small amount of data. First, we separate the images of the object into a diffuse reflection component and a specular reflection component by using linear polarizers. Then, we estimate the parameters of the reflection model for each component. Finally, we compress the difference between the input images and the rendered images by using wavelet transform. At the rendering stage, we first calculate the diffuse and specular reflection images from the reflection parameters, then add the difference decompressed by inverse wavelet transform into the calculated reflection images, and finally obtain the photorealistic image of the object.     

Synthesis and application of a silica nanocomposite filler using water glass and a resole‐type phenol resin

Composite plastics in which silica was dispersed homogeneously were prepared from a resole‐type phenol resin and a silica‐sol using water glass. The silica (10–50 nm) was dispersed into resin particles of 2–20 μm in size. The powder that was obtained (nanocomposite filler) and a curing reagent were then mixed, and the resulting mixture was processed by using heat and pressure to yield plastics containing nanocomposite fillers. The coefficients of friction factor of the resulting plastics composites decreased by half and the amount of wear that they suffered decreased to just one tenth of that of the unfilled material, while their wear‐resistance was greatly improved. The new plastics displayed good sliding properties, while also maintaining good fluidity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Duplicated insertion mutation in the microtubule-associated protein Spag5 (astrin/MAP126) and defective proliferation of immature Sertoli cells in rat hypogonadic (hgn/hgn) testes

Male rats with hypogonadism (hgn/hgn) experience sterility from testicular dysplasia, which is controlled by a single recessive gene, hgn. The postnatal growth of the seminiferous tubules was severely affected. In this study, we localized the hgn locus to a 320 kb region on rat chromosome 10 and detected the insertion of a 25 bp duplication into the sixth exon of the sperm-associated antigen 5 (Spag5/astrin/MAP126) gene, which codes for a microtubule-associated protein. This mutation results in a truncated Spag5 protein lacking the primary spindle-targeting domain at the C terminus. Immunological staining with antibodies to markers for Sertoli and germ cells during the early postnatal period indicated that the abnormal mitosis with dispersed chromosomes in hgn/hgn testes occurs in proliferating Sertoli cells. Therefore, apoptotic Sertoli cell death would result from the disorganization of the spindle apparatus caused by defective Spag5. These findings suggested that the Spag5 is essential for testis development in rats and that the hgn/hgn rat is a unique animal model for studying the function of Spag5.     

Survey of a catalyst system for living cationic polymerization of glucose‐carrying vinyl ethers with acetyl and isopropylidene protecting groups

This study concerns the living cationic polymerization of two vinyl ethers (VEs) having pendant glucose residues, in which the hydroxyl groups are protected by acetyl and isopropylidene functions. Living cationic polymerization of VE having an acetyl‐protected glucose was achieved by employing an initiating system consisting of the CF₃COOH adduct of isobutyl VE (IBVE) and ethylaluminium dichloride in the presence of an added base at 0 °C. In contrast, the use of the HCl adduct of IBVE in conjunction with zinc iodide at ?15 °C was more suitable for the controlled polymerization of VE having an isopropylidene‐protected glucose. Polymers obtained under these reaction conditions had narrow molecular weight distributions (M_w/M_n ～ 1.1) and controlled molecular weights. © 2001 Society of Chemical Industry     

One-way simple multihead finite automata

The first half of this paper investigates the accepting powers of various types of simple one-way multihead finite automata. It is shown that(1)for each k?1, simple one-way (k+1)-head finite automata are more powerful than simple one-way k-head finite automata.(2)for each k?2, nondeterministic simple one-way k-head finite automata are more powerful than deterministic ones, and(3)for each k?2, sensing simple one-way k-head finite automata are more powerful than non-sensing ones.In the latter half, closure properties for various types of simple one-way multihead finite automata are investigated.Finally, we demonstrate that languages accepted by nondeterministic sensing simple one-way 2-head finite automata are related to some open problem concerning deterministic and nondeterministic tape-bounded Turing computations.