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Aomori Shi, Japan

Aomori University is a private university located in the city of Aomori, Japan, founded in 1968. Wikipedia.

Honda M.,University of Tokyo | Athar M.S.,Aligarh Muslim University | Kajita T.,University of Tokyo | Kasahara K.,Waseda University | Midorikawa S.,Aomori University
Physical Review D - Particles, Fields, Gravitation and Cosmology

We extend our calculation of the atmospheric neutrino fluxes to polar and tropical regions. It is well known that the air density profiles in the polar and the tropical regions are different from the mid-latitude region. Also there are large seasonal variations in the polar region. In this extension, we use the NRLMSISE-00 global atmospheric model J.M. Picone, J. Geophys. Res. 107, SIA 15 (2002), replacing the U.S.-standard 1976 atmospheric model, which has no positional or seasonal variations. With the NRLMSISE-00 atmospheric model, we study the atmospheric neutrino flux at the polar and tropical regions with seasonal variations. The geomagnetic model international geomagnetic reference field (IGRF) we have used in our calculations seems accurate enough in the polar regions also. However, the polar and the equatorial regions are the two extremes in the IGRF model, and the magnetic field configurations are largely different from one another. Note that the equatorial region is also the tropical region generally. We study the effect of the geomagnetic field on the atmospheric neutrino flux in these extreme regions. © 2015 American Physical Society. Source

Yamazaki A.,Tohoku University | Kidachi Y.,Aomori University | Minokawa T.,Tohoku University
Development Growth and Differentiation

Blastomere composition and expression profiles of wnt8 and hox11/13b orthologues were examined in the primitive indirect-developing echinoid Prionocidaris baculosa. We found that blastomere composition in the 16-cell-stage Prionocidaris embryos was different from that of the indirect-developing echinoids belonging to Euechinoidea, a derived group of the echinoids. The sizes of the blastomeres in the 16-cell-stage embryo varied, and no embryos formed a "micromere quartet," a group of four equal-sized micromeres. The smallest blastomere was usually located around the vegetal pole. We also found significant differences in early expression profiles of wnt8 orthologues of the Prionocidaris and euechinoids. Unlike euechinoids, the expression of wnt8 orthologue of Prionocidaris was not detected at the 16-cell stage; it began at the 32-cell stage in the broad area containing the vegetal pole. However, in later stages, the expression profiles of hox11/13b and wnt8 orthologues of Prionocidaris were similar to that of euechinoid orthologues. The present study suggests that there are considerable differences between Prionocidaris and euechinoids in early developmental mechanisms in the vicinity of the vegetal pole. © 2012 Japanese Society of Developmental Biologists. Source

Arai K.,Tokyo University of Science | Ishimitsu T.,Tokyo University of Science | Fushinobu S.,University of Tokyo | Uchikoba H.,University of Tokyo | And 2 more authors.
Proteins: Structure, Function and Bioinformatics

Lactobacillus casei L-lactate dehydrogenase (LCLDH) is activated through the homotropic and heterotopic activation effects of pyruvate and fructose 1,6-bisphosphate (FBP), respectively, and exhibits unusually high pH-dependence in the allosteric effects of these ligands. The active (R) and inactive (T) state structures of unliganded LCLDH were determined at 2.5 and 2.6 Å resolution, respectively. In the catalytic site, the structural rearrangements are concerned mostly in switching of the orientation of Arg171 through the flexible intersubunit contact at the Q-axis subunit interface. The distorted orientation of Arg171 in the T state is stabilized by a unique intra-helix salt bridge between Arg171 and Glu178, which is in striking contrast to the multiple intersubunit salt bridges in Lactobacillus pentosus nonallosteric L-lactate dehydrogenase. In the backbone structure, major structural rearrangements of LCLDH are focused in two mobile regions of the catalytic domain. The two regions form an intersubunit linkage through contact at the P-axis subunit interface involving Arg185, replacement of which with Gln severely decreases the homotropic and hetertropic activation effects on the enzyme. These two regions form another intersubunit linkage in the Q-axis related dimer through the rigid NAD-binding domain, and thus constitute a pivotal frame of the intersubunit linkage for the allosteric motion, which is coupled with the concerted structural change of the four subunits in a tetramer, and of the binding sites for pyruvate and FBP. The unique intersubunit salt bridges, which are observed only in the R state structure, are likely involved in the pH-dependent allosteric equilibrium. © 2009 Wiley-Liss, Inc. Source

Okada Y.,Kyorin University | Tanaka K.,Kyorin University | Sato E.,Aomori University | Okajima H.,Kyorin University
JAOCS, Journal of the American Oil Chemists' Society

Reliable quantitative kinetic data on the antioxidant activity of capsaicin (CAP) is lacking, and the antioxidative mechanism of CAP is still unclear. Therefore, an investigation aimed at elucidating the antioxidative sites of CAP that react with chain-propagating peroxyl radicals was undertaken. First, the reaction of CAP with 2,2-diphenyl-1-picrylhydrazyl (DPPH) was investigated, and it was found that the stoichiometric factor of CAP is 2. Then, the rate constant for the reaction of CAP with peroxyl radicals derived from cumene was measured. CAP reacted with peroxyl radicals at a constant rate of k inh = 5.6 × 103 M-1 s-1. Furthermore, the inhibitory effects of various related compounds against cumene oxidation were measured, showing that the phenolic OH group is the active portion of the molecule. In addition, the kinetic solvent effects of DPPH/CAP reactions were measured in methanol, acetonitrile, acetone and tetrahydrofuran. In particular, an enhancement in the reaction rate was observed in alkaline methanol, indicating that these results are due to the partial ionization of the phenol of CAP and very fast electron transfers from the phenolate anion to DPPH. We interpreted these results as indicating that the phenolic OH group of CAP is mainly associated with peroxyl radical scavenging. © 2010 AOCS. Source

Sajjad Athar M.,Aligarh Muslim University | Honda M.,University of Tokyo | Kajita T.,University of Tokyo | Kasahara K.,Waseda University | Midorikawa S.,Aomori University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics

We present the calculation of the atmospheric neutrino fluxes for the neutrino experiments proposed at INO, South Pole and Pyhäsalmi. Neutrino fluxes have been obtained using ATMNC, a simulation code for cosmic ray in the atmosphere. Even using the same primary flux model and the interaction model, the calculated atmospheric neutrino fluxes are different for the different sites due to the geomagnetic field. The prediction of these fluxes in the present Letter would be quite useful in the experimental analysis. © 2012 Elsevier B.V. Source

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