• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2003.10a
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• pp.135-135
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• 2003

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.12
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• pp.868-873
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• 1987

In this pater, we have proposed a synthetic main chopper circuit for the chopper controlled electric automobile. The proposed chopper circuit operates as a step-down chopper in powering mode and as a polarity reversion type chopper in regenerative braking mode. In this study, it was found that powering and regenerative braking operations using the separately excited D.C motor can be controlled continuously only by gate signals of the chopper without changing the connection of the circuit.

• The Pure and Applied Mathematics
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• v.18 no.2
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• pp.129-139
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• 2011

We consider an optimal trading rule in this paper. We assume that the underlying asset follows a mean-reverting process and the transaction consists of one buying and one selling. To maximize the profit, we find price levels to buy low and to sell high. Associated HJB equations are used to formulate the value function. A verification theorem is provided for sufficient conditions. We conclude the paper with a numerical example.

• Korean journal of food and cookery science
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• v.17 no.6
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• pp.617-624
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• 2001

Gamma irradiation (1-10 kGy) was applied to chicken for the evaluation of their microbiological safety and possible genotoxicity. In 3 kGy-irradiated sample, the growth of psychrophile was inhibited about 1.5 log cycles and no cells were recovered in total microbial counts. All kinds of contaminated microorganism were sterilized by 7 kGy-irradiation. Also, irradiation followed by freeze-storage at the same time was very effective in inhibiting bacterial growth. The genotoxicity of 10 kGy-irradiated chicken was evaluated by Salmonella Typhimurium reversion assay and in vivo micronucleus assay using mouse bone marrow cells. The results were negative in the bacterial reversion assay with S. Typhimurium TA98, TA100, TA1535, and TA1539. Clastogenic effects were not shown in vivo mouse micronucleus assay at 10 kGy-dose tested.

• KSBB Journal
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• v.14 no.2
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• pp.248-254
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• 1999

Adverse reactions after injection of diphtheria vaccine are induced by impurities present in crude toxoids that cannot be removed completely by purification of toxoids after formalization. To increase toxoid purity, toxin purification was tried before formalization. Crude toxin was purified with ultrafiltration and ion-exchange chromatography. Purified toxin purity was improved 2.9 times higher than crude toxin, and purity was 2,560 Lf/mg PN. Purified toxin was detoxified with formalin and lysine, and potency test were performed. Toxoid, prepared from toxin treated with formalin and lysine, did not show reversion to toxin and purity was higher than the toxoid purified after formalization. Therefore, we concluded that the use of toxoid vaccine prepared from toxin purified is a useful method of minimize adverse reaction after injection of diphtheria vaccine.

• Toxicological Research
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• v.14 no.3
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• pp.453-457
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• 1998

In order to evaluate the mutagenic potential of Intralipidos produced by Greenmate cooperation. We performed Salmonella typhimurium reversion assay, chromosomal aberration test on chinese hamster ovarian cells and in vivo micronucleus assay using mouse bone marrow cells. In the reverse mutation test using Salmonella typhimurium TA98 and TA100, Intralipidos did not increase the number of revertant at any of the concentration tested in this study. Intralipidos did not increase the number of cells having structural or numberical chromosome aberration in cytogenetic test. In mouse micronucleus test, no significant increase were observed in the occurrence of micornucleated polychromatic erythrocytes in ICR male mice intraperitoneally administered with Intralipidos. These results indicate that Intralipidos has no genetic toxicity under these experimental conditions.

• Toxicological Research
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• v.14 no.3
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• pp.427-433
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• 1998

The acute and genetic toxicity of DK1002 was subjected in this study. DK1002 which is a morphine-like new drug candidate synthesized by Dong-Kook Pharmaceutical Co. Ltd. is now under developing as a analgesics that have better drug efficacy and least addictive property. In acute toxicity study, the 50% lethal doses ($LD_{50}$) of DK1002 were determined as>2000mg/kg (p.o.), 237.0mg/kg(i.p.), 57.5mg/kg(i.v.), and 1266.9mg/kg (s.c.). And also, to study the genotoxicity of DK1002, we performed bacterial reversion assay with Salmonella typhimurium TA98, TA100, TA1535, and TA1537, and in vitro chromosomal aberration assay with Chinese hamster lung cells in the presence and absence of S-9 metabolic activation system. In vivo micronucleus assay using mouse bone marrow cells was also performed. From these results, DK1002 was revealed nonmutagenic potential in S. typhimurium TA98, TA100, TA1535, and TA537 both in the absence and presecne of metablic activation system. No clastogenicity of DK1002 was observed in chromosomal aberration assay in vitro as well as in micronucleus assay in vivo.

• THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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• v.7 no.1
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• pp.99-107
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• 2001

In the present studies, decursinol angelate, decursin isolated from Angelica gignatis radix and oil fraction of Cnidii rhizoma was analyzed by normal phase HPLC and GC/MS respectively. The standardized water extracts of Angelica gignatis radix, Cnidii rhizoma and its complex named Gung-gui-tang was tested the anti mutagenic effects by in vitro genotoxicity using Salmonella reversion assay (Ames test) and micronucleus test in chinese hamster ovary(CHO) cells. Angelica gignatis radix, Cnidii rhizoma and Gung-gui-tang was not exhibited the antimutagenic effects in the Salmonella reversion assays with or without metabolic activation. However, the micronucleus test assays, Angelica gignatis radix and Gung-gui-tang was showed the antimutagenic effects significantly. The maximum inhibition observed with Gung-gui-tang was reduced by 59% in the micronucleus test without metabolic activation. In this paper, results are presented on the availability of potential antimutagenic activity of the water extracts of Gung-gui-tang.

• Microbiology and Biotechnology Letters
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• v.24 no.1
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• pp.105-110
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• 1996

Mugwort has been known as a traditional substitutive foodstuff and as showing a physiologically beneficial function to a human being. Therefore, effect of mugwort extract in terms of mutagenicity and desmutagenicity was investigated to berify its function. Ethanol extract from mugwort did not exhibit any mutagenicity. On the contrary, inhibitory effects of the ethanol extract were observed on mutagenicity induced by aflatoxin $B_{1}(AFB_1)$, 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole(Trp-P-1), 3-amino-1-methyl-5H-pyrido[4,3-b]indole(Trp-P-2) and 2-nitroflourene(2NF) using Salmonella typhimurium reversion assay. On direct-acting mutagen(2NF, 3${\mu}$g/plate), ethanol extract showed a slight inhibitory effect of 19.7~22.9%, however on indirect-acting mutagen such as AFB1(2${\mu}$g/plate), Trp-P-1(1${\mu}$g/plate) and Trp-P-2(1${\mu}$g/plate), we observed higher inhibitory effect of 47.9~61.2%, 64.1~70.7%, 67.4~78.7%, respectively. Step-wise fractionation of the ethanol extract was done by using hexane, chloroform, ethyl acetate and water to obtain effective fraction. Among them, hexane, chloroform, and ethyl acetate fractions showed high inhibition of 63.0~80.0%, 77.5~82.1%, and 68.5~83.1%, respectively on the mutagenicity of $AFB_1$ in Sal. typhimurium TA98. Consequently, these results indicated that mugwort extract contains some compound(s) which may show desmutagenicity.

• Polymer(Korea)
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• v.25 no.1
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• pp.63-70
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• 2001

The objective of this study was to investigate the effect of cure type on the processing and physical properties under conditions of similar stress-strain properties. On the carbon black filled natural rubber(NR) based compound, the induction time decreased, but the cure rate became fast with increasing loading of sulfur donor agent. Tensile strength was little affected on the curing type. However, elongation generally decreased with increasing accelerator. Effect of cure type on the blow-out properties was followings: CV