Research Institute of Natural science

Kita-ku, Japan

Research Institute of Natural science

Kita-ku, Japan
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Kang K.H.,Korea Advanced Institute of Science and Technology | Sung N.-J.,Research Institute of Natural Science | Kim J.G.,Korea Advanced Institute of Science and Technology | Kim S.-H.,Gyeongsang National University | And 2 more authors.
Journal of the Korean Society of Food Science and Nutrition | Year: 2016

Nitrite and dimethylamine (DMA) are the immediate precursors of carcinogenic N-nitrosodimethylamine (NDMA). This study investigated the effects of nitrite and nitrate contents in Chinese cabbage on changes in NDMA, nitrite, nitrate, and DMA contents during storage of kimchi. Contents of nitrite in Chinese cabbage 1 (HNC), Chinese cabbage 2 (MNC), and Chinese cabbage 3 (LNC) were 47.54±1.07, 10.12±0.31, and 6.10±0.09 mg/kg, respectively. Kimchi were assigned to one of the following three groups: kimchi used HNC (HNK), kimchi used MNC (MNK), and kimchi used LNC (LNK). HNK had higher levels of nitrite and nitrate than those in MNK and LNK after storage for 10 days and 20 days. DMA and NDMA contents decreased in all kimchi during the storage period. HNK had higher NDMA content than LNK until 20 days of storage. These results suggest that the contents of nitrite and nitrate in Chinese cabbage have significant effects on the formation of NDMA in kimchi. © 2016, Korean Society of Food Science and Nutrition. All rights reserved.

Ki J.-S.,Sangmyung University | Lee Y.-M.,Sangmyung University | Jung S.-O.,Research Institute of Natural science | Horiguchi T.,Japan National Institute of Environmental Studies | And 2 more authors.
Molecular Phylogenetics and Evolution | Year: 2010

Class Gastropoda includes a large number of described species, many with extensively rearranged mitochondrial genomes. We sequenced the mitogenome of the rock shell, Thais clavigera (Gastropoda: Muricidae), an intertidal snail, using long PCR with primers designed on the basis of expressed sequence tags. The mitogenome of T. clavigera consists of 2 rRNAs, 22 tRNAs, and 13 protein-coding genes, but no control region. Structural comparisons revealed that the order Sorbeoconcha, including T. clavigera, have nearly identical mitochondrial gene patterns. However, they have an inversion between a tRNAPhe-tRNAGlu cluster that comprises 21 genes, but most of the remaining structure is similar to the putative mollusk ground pattern. These findings will provide a better insight into mitochondrial gene rearrangement over the course of gastropod evolution. © 2009 Elsevier Inc. All rights reserved.

Park D.K.,Research Institute of Natural Science | Lee S.J.,Research Institute of Natural Science | Lee J.-H.,Research Institute of Natural Science | Choi M.Y.,Research Institute of Natural Science | Han S.W.,KAIST
Chemical Physics Letters | Year: 2010

The effect of polymeric stabilizers on the catalytic activity of Pt nanoparticles for an electron-transfer reaction between Fe (CN) 6 3 - and S 2 O 3 2 - was investigated. Pt nanoparticles were prepared by laser ablation of Pt plate in water, and then stabilized with typical stabilizing polymers such as poly(vinyl pyrrolidone) (PVP), poly(vinyl sulfate) (PVS), and polyethyleneimine (PEI). The catalytic reaction proceeds much faster with PEI-stabilized nanoparticles than PVP- or PVS-stabilized particles. The activity of nanoparticles also highly depends on pH and polymer concentration. These clearly demonstrate that the net charge of the stabilizers plays a decisive role for the nanoparticle-mediated electron transfer between charged reactants. © 2009 Elsevier B.V. All rights reserved.

Chung W.S.,Research Institute of Natural Science | Gavrilik A.M.,NASU Bogolyubov Institute for Theoretical Physics | Kachurik I.I.,NASU Bogolyubov Institute for Theoretical Physics | Kachurik I.I.,Khmelnytskyi National University | Rebesh A.P.,NASU Bogolyubov Institute for Theoretical Physics
Journal of Physics A: Mathematical and Theoretical | Year: 2014

In this paper we propose a symmetric q-deformed Tamm-Dancoff (S-TD) oscillator algebra and study its representation, coordinate realization, and main properties. In particular, the non-Fibonacci (more exactly, quasi-Fibonacci) nature of the S-TD oscillator is established, the possibility of relating it to a certain p, q-deformed oscillator family is shown, and the occurrence of pairwise accidental degeneracy is proven. We also find the coherent state for the S-TD oscillator and show that it satisfies a completeness relation. The main advantage of the S-TD model over the usual Tamm-Dancoff oscillator is that due to the q 虠 q-1symmetry, it admits not only real, but also complex (phaselike) values of the deformation parameter q. © 2014 IOP Publishing Ltd.

Samuel V.O.,Indian Institute of Science | Sajeev K.,Indian Institute of Science | Hokada T.,Japan National Institute of Polar Research | Horie K.,Japan National Institute of Polar Research | Itaya T.,Research Institute of Natural science
Tectonophysics | Year: 2015

The Nilgiri Block, southern India is an exhumed lower crust formed through arc magmatic processes in the Neoarchean. The main lithologies in this terrane include charnockites, gneisses, volcanic tuff, metasediments, banded iron formation and mafic-ultramafic bodies. Mafic-ultramafic rocks are present towards the northern and central part of the Nilgiri Block. We examine the evolution of these mafic granulites/metagabbros by phase diagram modeling and U-Pb sensitive high resolution ion microprobe (SHRIMP) dating. They consist of a garnet-clinopyroxene-plagioclase-hornblende-ilmenite±orthopyroxene±rutile assemblage. Garnet and clinopyroxene form major constituents with labradorite and orthopyroxene as the main mineral inclusions. Labradorite, identified using Raman analysis, shows typical peaks at 508cm-1, 479cm-1, 287cm-1 and 177cm-1. It is stable along with orthopyroxene towards the low-pressure high-temperature region of the granulite facies (M1 stage). Subsequently, orthopyroxene reacted with plagioclase to form the peak garnet+clinopyroxene+rutile assemblage (M2 stage). The final stage is represented by amphibolite facies-hornblende and plagioclase-rim around the garnet-clinopyroxene assemblage (M3 stage). Phase diagram modeling shows that these mafic granulites followed an anticlockwise P-T-t path during their evolution. The initial high-temperature metamorphism (M1 stage) was at 850-900°C and ~9kbar followed by high-pressure granulite facies metamorphism (M2 stage) at 850-900°C and 14-15kbar. U-Pb isotope studies of zircons using SHRIMP revealed late Neoarchean to early paleoproterozoic ages of crystallization and metamorphism respectively. The age data shows that these mafic granulites have undergone arc magmatism at ca. 2539.2±3Ma and high-temperature, high-pressure metamorphism at ca. 2458.9±8.6Ma. Thus our results suggests a late Neoarchean arc magmatism followed by early paleoproterozoic high-temperature, high-pressure granulite facies metamorphism due to the crustal thickening and suturing of the Nilgiri Block onto the Dharwar Craton. © 2015 Elsevier B.V.

Park Y.-S.,Research Institute of Natural science | Hoh J.-K.,Hanyang University | Park M.-I.,Hanyang University
Journal of Korean Medical Science | Year: 2012

The purpose of this study was to investigate the feasibility of different fetal heart rate (FHR) ranges in the nonstress test (NST) and to better understand the meaning of mild bradycardia and/or tachycardia without non-reassuring patterns. We employed the heredity to show that mild bradycardia (100-119 beats per minute, bpm) and mild tachycardia (161-180 bpm) regressed to the normal FHR range (120-160 bpm). We used linear regression to analyze FHR data from FHR tracings recorded 10 min before (NST, as the predictor) and 10 min after vibroacoustic stimulation testing (as the dependent variable). Acceleration for 15 bpm-15 seconds (Acc1515) and deceleration for 15 bpm-15 seconds (Dec1515) in the NST were also analyzed for each group. The slope of the best-fit line was the largest in the mild bradycardia group and the smallest in the normal range group. Dec1515 was most prominent in mild tachycardia and both the mild bradycardia and tachycardia groups regressed towards the mean FHR range. Therefore, we propose that both mild bradycardia and tachycardia of FHR in non-acute situations (range between 100 and 180 bpm) are not regarded a pathologic signal for clinical use. © 2012 The Korean Academy of Medical Sciences.

Chung W.S.,Research Institute of Natural Science
Modern Physics Letters A | Year: 2014

In this paper, we introduce the deformed algebra whose number operator is expressed in terms of the product of the creation operator and annihilation operator. We give some examples for these kinds of deformed algebras. For Arik-Coon's q-oscillator algebra, we discuss, especially, the photon-added states and the photon-subtracted states and construct their associated generation functions. © World Scientific Publishing Company.

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