• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.75-78
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• 2003

The organically bound tritium(OBT) concentrations of the marine organisms(seaweed and shellfish) around Wolsung nuclear power plants were measured. The OBT concentrations of seaweeds were in the range of $0.372{\sim}2.72$ Bq/kg-fresh. The OBT concentrations of shellfish were in the range of $0.239{\sim}2.02$ Bq/kg-fresh. The internal dose due to the OBT concentration of seaweed was estimated as $3.4{\times}10^{-7}$ mSv/year.

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.9-18
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• 2003

Rice plants at different seed-developing stages were exposed to HTO vapor in an exposure box for 1 h during daytime and nighttime to investigate the levels of tissue free water $^3H$ (TFWT) and organically bound $^3H$ (OBT) in different plant parts. In the daytime experiment, TFWT concentrations in leaves at the end of exposure $(h_0)$ were around 100% of the 1 hour mean HTO concentrations in air moisture whereas in the nighttime experiment, they were as low as $30{\sim}40%$ of the air concentration. TFWT concentrations in both experiments decreased very rapidly in the beginning but much mote slowly later and those at harvest were hundreds to hundred thousands times lower than those at $h_0$. OBT concentrations varied with time in different manners depending on plant parts and exposure times and differed between at $h_0$ and at harvest by factors of less than 10 on the whole. Even during nighttime exposures, OBT was produced at about a third the rate for daytime exposures. The degree of the conversion of airborne HTO into OBT in mature rice seeds, being several times higher in the daytime experiment than in the nighttime experiment, was highest after the exposure peformed at the most actively seed-developing stage for both experiments. It is estimated that OBT would contribute much more to the ingestion radiation dose than TFWT if rice plants are exposed to HTO vapor for the seed-developing period.

• Journal of Radiation Protection and Research
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• v.29 no.4
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• pp.213-219
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• 2004

Soybean plants were exposed to HTO vapor in an exposure box for 1 hour at different growth stages. Relative concentrations of TFWT at the end of exposure (percent ratios of TFWT concentrations to mean HTO concentrations in air moisture in the box during exposure) decreased on the whole in the order of leaf > shell > seed > stem with the highest values of 40.2% and 6.4% for leaf and stem, respectively. TFWT concentrations reduced by factors of several thousands to several hundred-thousands from the end of exposure till the harvest. The reduction factor decreased in the order of leaf > shell > seed > stem. Relative OBT concentrations at harvest (ratios of the OBT concentration in the dry plant part at harvest to the initial leaf TFWT concentration, ml $g^{-1}$) were in the range of $2.2{\times}10^{-5}{\sim}9.5{\times}10^{-3}$ for seeds being the highest when the exposure was performed at the actively seed-developing stage. The exposure time-dependent variation in the OBT concentration was much greater in seeds and shells than in leaves and stems. It was indicated that OBT would contribute to almost all the radiation dose due to the consumption of soybean seeds in most cases after an acute exposure of growing plants to HTO vapor. Present results are applicable to establishing and validating soybean $^3H$ models for an acute accidental release of HTO.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.336-336
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• 1998

• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.309.1-309
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• 2001

• Applied Biological Chemistry
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• v.36 no.1
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• pp.38-44
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• 1993

1) OBT7 mutant was isolated by W light-butanol tolerance from Clostridium saccharoperbutylacetonicm ATCC 13564 (N1-4 strain). The mutant produced 16.5 g/l (1.4-fold increase) of n-butanol, 4.65 g/l (1.5-fold increase) of acetone, and 21.5 g/l of total solvent. It was suggested that clostridial bacteria producing n-butanol does not have a poor effect on misrepair via an error-prone pathway by UV light-butanol tolerance. 2) Compared to glucose fermentation, in mannitol fermentation, OBT7 mutant did not produce acetone and acetic acid. And the ratios of n-butanol and ethanol to total solvents increased by 10.3% and 10.5%, respectively, totalling 20.8%, while the ratio of acetone was decreased by 21.2%. Also the maximum ratio of n-butanol to total solvents reached 94.8%. These results indicated that oxidized compound (acetone, acetic acid, and butyric acid) was converted to the reduced compounds (n-butanol, and ethanol). Therefore, mannitol can be used to eliminate by-products of oxidized compound.

• Journal of Sasang Constitutional Medicine
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• v.15 no.1
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• pp.90-108
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• 2003

Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) has been developed as prescriptions for the Soyeumin constitution. The hepatoprotective effect of the water extract of Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) was investigated against carbon tetrachloride (CCl4)-induced hepatic damage. A single intra-peritoneal injection of CCl4 produced liver damage in rats as manifested by the significant rise of aspartate aminotransferase(AST), alanine aminotransferase(ALT), and alkaline phosphatase(ALP) in serum as compared to those of untreated normal group. Pretreatments of rats with Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) 500 mg/kg for 7 days) were significantly reduced AST, ALT, and ALP levels compared with CCl4-treated control group. Treatment of rats with CCl4 led to significantly increase in lipid peroxidation and significantly decrease in cytochrome P450 and P450 reductase. The oral administration of Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) water extract significantly inhibited the accumulation of microsomal thiobarbituric acid reactive substance (TBARS) and increased the cytochrome P450 and P450 reductase activity. All these biochemical alterations resulting from CCl4 administration were inhibited by the pretreatment with Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SG1) extract. These results suggest that Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) water extract can be useful as a hepatoprotective agent. And the effect of NO modulation by NO synthesis or precursors, and Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang (SGT) water extract was researched on chronic liver damage induced by CCl4 administration. It was observed that endogenous NO protected the liver from lipid peroxidation, fibrosis, and damage. Osuyubujaijung-tang(OBT) and Sipyimiguanjung-tang(SGT) water extract showed the hepatoprotective effect on the chronic liver cirrhosis model and relationship with NO modulation.

• Proceedings of the Korean Nuclear Society Conference
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• 2003.05a
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• pp.333.2-333.2
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• 2003

• Journal of Radiation Protection and Research
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• v.28 no.1
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• pp.51-57
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• 2003

To assess the internal dose by $^3H\;&\;^{14}C$ in total diet of inhabitants near Wolsung Nuclear Power Plants, TFWT, OBT and $^{14}C$ concentration in total diet was analyzed for collection region and time. TFWT, OBT and $^{14}C$ concentrations were in the range of 3.19-42.2 Bq/L, 1.00-39.4 Bq/L, and 0.230-0.855 Bq/gC, respectively. The calculated annual effective dose with TFWT, OBT and $^{14}C$ is $6.10{\times}10^{-5}mSv/y,\;3.71{\times}10^{-5}mSv/y\;and\;7.08{\times}10^{-3}mSv/y$, respectively. And then annual internal dose with total diet for inhabitants near Wolsung NPPs is about $7.18{\times}10^{-3}mSv/y$, which is about 0.72% of annual effective dose limit 1 mSv/y.

• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.45-54
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• 2005

A dynamic compartment model was developed to appraise the level of the contamination of agricultural plants by accidentally released tritium from nuclear facility. The model consists of a set of inter-connected compartments representing atmosphere, soil and plant. In the model three categories of plant are considered: leafy vegetables, grain plants and tuber plants, of which each is modeled separately to account for the different transport pathways of tritium. The predictive accuracy of the model was tested through the analysis of the tritium exposure experiments for rice-plants. The predicted TFWT(tissue free water tritium) concentration of the rice ear at harvest was greatly affected by the absolute humidity of air, the ratio of root uptake, and the rate of rainfall, while its OBT(organically bound tritium) concentration the stowing period of the ear, the absolute humidity of air and the content of hydrogen in the organic phase. There was a good agreement between the model prediction and the experimental results lot the OBT concentration of the ear.