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Koriyama, Japan

Koriyama Women's University is a private college, located in the city of Kōriyama, Japan. Wikipedia.

Ishihara M.,Koriyama Womens University
Health Physics | Year: 2014

The authors investigated the fractal structure of the distributions of air dose rates in Koriyama city in Fukushima using data published by the Fukushima Prefectural and Koriyama City governments. Relative frequency data of air dose rates (strength distribution) could be well fitted with a q-distribution. In the present analysis, the relative frequency decreases approximately as s 5.5 for high air dose rate values, where the quantity s represents air dose rate. The fractal dimension is a function of the threshold s th of air dose rate. The fractal dimension is approximately 1.59 when sth is the average of the air dose rates in Koriyama (0.9 μSv h-1) and decreases with increasing the threshold: it is approximately 1.97 for sth = 0.6 μSv h-1 and 1.40 for sth = 1.2 μSv h-1. These results confirm that the strength distribution behaves like a power function for high air dose rate values and that the fallout pattern can be described as a fractal. Copyright © 2014 Health Physics Society. Source

Ishihara M.,Koriyama Womens University
International Journal of Modern Physics E | Year: 2016

The parametric resonance was studied in chiral phase transitions when the momentum distribution is described by a Tsallis distribution. A Tsallis distribution has two parameters, the temperature (Formula presented.) and the entropic index (Formula presented.). The amplification was estimated in two cases: (1) expansionless case and (2) one-dimensional (1D) expansion case. In an expansionless case, the temperature (Formula presented.) is constant, and the amplified modes as a function of (Formula presented.) were calculated for various (Formula presented.). In 1D expansion case, the temperature (Formula presented.) decreases as a function of the proper time, and the amplification as a function of the transverse momentum was calculated for various (Formula presented.). In the expansionless case, the following facts were found: (1) the larger the value (Formula presented.) is, the softer the amplified modes are for the first and second resonance bands, (2) the amplified mode of the first resonance band decreases and vanishes, as the temperature (Formula presented.) increases and (3) the amplified mode of the second resonance band decreases and approaches to zero, as the temperature (Formula presented.) increases. In 1D expansion case, the following facts were found: (1) the soft mode is amplified, (2) the amplification is extremely strong around the amplified mode of the first resonance band at (Formula presented.) and (3) the magnitude of the amplification as a function of transverse momentum oscillates around the amplified mode of the first resonance band at (Formula presented.). © 2016 World Scientific Publishing Company Source

Kamata R.,Kitasato University | Shiraishi F.,Japan National Institute of Environmental Studies | Kageyama S.,Koriyama Womens University | Nakajima D.,Japan National Institute of Environmental Studies
Toxicology in Vitro | Year: 2015

Polychlorinated biphenyls (PCBs) are thought to exert their toxicities mainly by binding to the aryl hydrocarbon receptor and by stimulating transcription of various genes, notably metabolizing enzymes including the cytochrome P450 (CYP) 1 family. However, PCBs and their metabolites could have potential to activate other nuclear receptors and subsequent events. We focused on the constitutive androstane receptor (CAR) inducing CYP2B and measured the agonistic activity of PCBs and mono-hydroxylated PCBs (OH-PCBs) to the CAR using yeast cells transduced with the human CAR and its response pathway. Twenty-nine of 34 tested PCBs and 72 of 91 OH-PCBs exhibited CAR agonistic effects. Of 41 OH-PCBs that had the same chlorination patterns as the tested PCBs, 9 had activities more than twice those of their non-hydroxylated analogs. In particular, 2',4',6'-trichlorobiphenyl-4-ol and 2,2',4',6'-tetrachlorobiphenyl-4-ol were 332- and 22-fold more potent than their analogs and were 15 times and 2.8 times, respectively, as active as a reference substance, 4-. tert-octylphenol. The activities of 17 of the OH-PCBs were reduced to less than half those of their non-hydroxylated analogs. Four OH-PCBs derived from 3 active PCBs were inactive. However, a consistent relationship between hydroxyl substituent position and activity could not be discerned. Comprehensive evaluation of the toxic potential of PCBs and their hydroxylated metabolites and their concentrations in the environment are required. © 2015 Elsevier Ltd. Source

Ishihara M.,Koriyama Womens University
European Physical Journal C | Year: 2013

We attempt to describe a domain using a squeezed state within quantum field theory. An extended squeeze operator is used to construct the state. Using a scalar field theory, we describe a domain in which the distributions of the condensate and of the fluctuation are both Gaussian. The momentum distribution, chaoticity, and correlation length are calculated. It is found that the typical value for the momentum is approximately the inverse of the domain size. It is also found that the chaoticity reflects the ratio of the size of the squeezed region to that of the coherent region. The results indicate that the quantum state of a domain is defined by these quantities under the assumption that the distributions are Gaussian. As an example, this method is applied to a pion field, and the momentum distribution and chaoticity are shown. © 2013 Springer-Verlag Berlin Heidelberg and Società Italiana di Fisica. Source

Kanke N.,Niigata University | Kanke N.,Koriyama Womens University | Takazawa E.,Niigata University
Geological Society Special Publication | Year: 2014

We report the major element compositions of constituent minerals in 278 harzburgites and of 101 whole rocks from the northern Fizh mantle section in the northern Oman Ophiolite to investigate the formation and evolution of oceanic lithospheric mantle. Olivine Fo varies from 90 to 92 whereas spinel Cr# (=Cr/(Cr + Al) atomic ratio) varies from 0.15 to 0.78. The Cr# of spinels in a large number of harzburgites exceeds 0.6, which is the upper bound for abyssal peridotites. In the northern Fizh mantle section, highly refractory harzburgites with spinel Cr# greater than 0.7 are distributed in a 3-km-wide band along a NW-SE-striking shear zone. We infer a two-stage depletion process in the northern Fizh mantle section. In the first stage, asthenospheric mantle was partially melted beneath a mid-ocean ridge, producing a harzburgitic residual column. In the second stage during detachment of oceanic lithosphere an H2O-rich fluid, released from the metamorphic sole due to thermal metamorphism of altered oceanic crust, extensively infiltrated the northern Fizh mantle section where the ridge segment boundary region was previously located. The residual harzburgites were subjected to flux melting, resulting in a highly refractory harzburgite zone with spinel Cr# greater than 0.7. © The Geological Society of London 2014. Source

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