Cloning, sequence analysis, and expression in Escherichia coli of gene encoding N-Benzyl-3-pyrrolidinol dehydrogenase from Geotrichum capitatum

The gene encoding N-benzyl-3-pyrrolidinol dehydrogenase (DDBJ/EMBL/GenBank accession no. AB294179), a useful biocatalyst for producing (S)-N-benzyl-3-pyrrolidinol, was cloned from the genomic DNA of Geotrichum capitatum JCM 3908. The gene contained an open reading frame consisting of 1023 nucleotides corresponding to 340 amino acid residues. The subunit molecular weight was calculated to be 39,000. The predicted amino acid sequence did not have significant similarity to those of N-benzyl-3-pyrrolidinone reductases reported previously. From 30 mM N-benzyl-3-pyrrolidinone, (S)-N-benzyl-3-pyrrolidinol was obtained with a yield >99.9% and an enantiomeric excess >99.9% in 1-h and 2-h reactions without NADH addition by the resting cells of Escherichia coli HB 101 strains harboring the expression plasmids pSG-POBS and pSF-POBS that possess the glucose dehydrogenase gene and formate dehydrogenase gene as an NADH-reproducing system, respectively, besides the N-benzyl-3-pyrrolidinol dehydrogenase gene. N-Benzyl-3-pyrrolidinol dehydrogenase activity (0.56 U/mg) was observed in E. coli (pSG-POBS), which was 17-fold the specific activity observed in G. capitatum JCM 3908.     

Exploration of communication models in the design of distributed embedded systems

Distributed embedded systems involve communication in various layers, and therefore their design is more difficult than of single embedded systems. This paper presents how communication exploration can be done in a design process of distributed embedded systems using an example of event‐triggered and time‐triggered communication. A design process begins from abstract specification without assuming any communication category, then explores the categories in a stepwise manner, followed by physical implementation synthesis. This encourages stepwise decision making, component and framework reuse, and early stage verification. Copyright © 2007 Institute of Electrical Engineers of Japan© 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

Material design method for the functionally graded cemented carbide tool

The aim of this study is to apply the concept of functionally graded materials (FGMs) to tool materials and to develop high-performance cutting tools. The requirement of the graded structure is that the surface is highly wear resistant cermet, and the inside is tough cemented carbide. Compressive residual stress was introduced to the material surface by grading the composition. To develop the new material, the cutting condition of broken cermet was investigated and their cutting temperature distribution was measured by a newly developed measuring method. Then Computer Aided Engineering (CAE) analysis was performed to calculate the generated thermal stress. The new material was developed with the aim to introduce the compressive residual stress over the calculated thermal stress. As a result developed tools demonstrated higher wear resistance, breakage resistance, thermal crack resistance and peeling resistance over those of conventional tools in the market.     

Another multiheme protein, hydroxylamine oxidoreductase, abundantly produced in an anammox bacterium besides the hydrazine-oxidizing enzyme

A hydroxylamine oxidoreductase (HAO) was purified from anammox sludge in which an anammox bacterium, strain KSU-1, was dominant. The enzyme was a 118-kDa homodimer composed of a 53-kDa subunit. With phenazine methosulfate and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide as electron acceptors, the V(max) and K(m) for hydroxylamine were determined as 9.6+/-0.2 micromol/min x mg and 33+/-2 microM, while those for hydrazine were 0.54+/-0.0 micromol/min x mg and 25+/-2 microM, respectively. The HAO had a P468 chromophore. These enzymatic properties were different from those of the hydrazine-oxidizing enzyme (HZO), a multiheme protein abundantly produced by the KSU-1 strain, but were similar to those of the HAO purified from Candidatus Brocadia anammoxidans. The hao gene exists upstream of the hzoB gene, which codes for the HZO. The sequence deduced from the hao gene indicated eight c-type heme binding motifs and showed 87% identity with a polypeptide encoded by an open reading frame (kustc1061) in the genome of an anammox bacterium Candidatus Kuenenia stuttgartiensis. These suggested that the HAO is an indispensable enzyme and well conserved in anammox bacteria, similar to the HZO. This enzyme might therefore be a specific hydroxylamine oxidoreductase for anammox bacteria.     

Refactoring pattern matching

Defining functions by pattern matching over the arguments is advantageous for understanding and reasoning, but it tends to expose the implementation of a datatype. Significant effort has been invested in tackling this loss of modularity; however, decoupling patterns from concrete representations while maintaining soundness of reasoning has been a challenge. Inspired by the development of invertible programming, we propose an approach to program refactoring based on a right-invertible language rinv—every function has a right (or pre-) inverse. We show how this new design is able to permit a smooth incremental transition from programs with algebraic datatypes and pattern matching, to ones with proper encapsulation, while maintaining simple and sound reasoning.     

In-situ powder neutron diffraction study on the formation process of LaMg2NiH7

The formation process from the intermetallic compound LaMg₂Ni to a complex hydride (deuteride) LaMg₂NiD₇ composed of La³⁺, 2 × Mg²⁺, [NiD₄]^4?, and 3 × D^? was investigated by in-situ powder neutron diffraction under deuterium gas pressure at room temperature. Below 0.001 MPa, small amount of deuterium was initially dissolved in the lattice of LaMg₂Ni forming LaMg₂NiD_0.05 and two new hydride phases (LaMg₂NiD_x1 and LaMg₂NiD_x2) were continuously yielded. Furthermore, LaMg₂NiD_4.6 with NiD_1.9 and NiD_3.3 units and interstitial deuterium atoms was formed prior to appearing of LaMg₂NiD₇. From their Bragg peak positions, the deuterium contents x1, and x2 were inferred as 0.05 < x1 < x2 < 4.6. At approximately 0.001 MPa, LaMg₂NiD₇ started forming. Since the intermediate deuterides had similar metal atomic framework of LaMg₂Ni, we revealed that LaMg₂NiD₇ formation proceeded through multiple deuteride phases with maintaining of the metal atomic framework of LaMg₂Ni.     

Therapeutic Effects of Quetiapine and 5-HT1A Receptor Agonism on Hyperactivity in Dopamine-Deficient Mice

Some diseases that are associated with dopamine deficiency are accompanied by psychiatric symptoms, including Parkinson’s disease. However, the mechanism by which this occurs has not been clarified. Previous studies found that dopamine-deficient (DD) mice exhibited hyperactivity in a novel environment. This hyperactivity is improved by clozapine and donepezil, which are used to treat psychiatric symptoms associated with dopamine deficiency (PSDD). We considered that DD mice could be used to study PSDD. In the present study, we sought to identify the pharmacological mechanism of PSDD. We conducted locomotor activity tests by administering quetiapine and drugs that have specific actions on serotonin (5-hydroxytryptamine [5-HT]) receptors and muscarinic receptors. Changes in neuronal activity that were induced by drug administration in DD mice were evaluated by examining Fos immunoreactivity. Quetiapine suppressed hyperactivity in DD mice while the 5-HT_1A receptor antagonist WAY100635 inhibited this effect. The number of Fos-positive neurons in the median raphe nucleus increased in DD mice that exhibited hyperactivity and was decreased by treatment with quetiapine and 5-HT_1A receptor agonists. In conclusion, hyperactivity in DD mice was ameliorated by quetiapine, likely through 5-HT_1A receptor activation. These findings suggest that 5-HT_1A receptors may play a role in PSDD, and 5-HT_1A receptor-targeting drugs may help improve PSDD.     

Electronic structure of wurtzite- and zinc blende-GaN studied by angle-resolved photoemission

The valence band structures of both wurtzite- and zinc blende-GaN were investigated by angle-resolved photoemission spectroscopy. It was found the k dispersions of the upper valence bands show band structures corresponding to wurtzite or zinc blende structure. In wurtzite-GaN, band width of the upper valence band is 6.7 eV in good agreement with the theoretically predicted value. However, the binding energy of Ga 3d level was found to be 15.7 eV relative to the valence band maximum, which is about 2 eV higher binding energy than those predicted by local density approximation calculations. In zinc blende-GaN, some discrepancies in the binding energy of the topmost bands around the valence band maximum was observed. We discuss the cause of these discrepancies by taking into account the strain effect.     

Variation in Texture and Lankford Value of 1070 Aluminum Sheet Rolled by Cone-shaped Roll

A rolling with cone-shaped roll, the diameter of which continuously varies along the axial direction, has been proposed as a new shear rolling for controlling the texture of an aluminum alloy sheet. In this study, variations in the texture and Lankford value of a 1070 aluminum sheet rolled by the cone-shaped roll were investigated. Rolling with the cone-shaped roll was found to impose intense shear strain at the edges of the specimen, specifically near the surface. The shear directions in the left and right portions of the specimen were opposite to each other. The surface and middle layer of the specimen rolled by the cone-shaped roll and the reference specimen were characterized by a shear texture and typical recrystallization texture components, respectively. Notably, the specimen rolled by the cone-shaped roll exhibited smaller texture intensity than the reference specimen, especially at the surface, and the shear texture-components were observed at relatively deeper positions. As a result of Lankford value measurements, the specimen rolled with the cone-shape roll exhibited a smaller planar anisotropy than the reference specimen and an average Lankford value close to unity, which are likely due to the texture modifications introduced during rolling with the cone-shaped roll.