• Journal of Radiation Protection and Research
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• v.20 no.4
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• pp.255-263
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• 1995

Root uptakes of $^{54}Mn,\;^{60}Co,\;^{85}Sr\;and\;^{137}Cs$ by rice were studied through a greenhouse experiment in which the upper 20 cm of the culture box was filled with an acidic loamy-sandy soil and a mixed solution of the radionuclides was applied to the surface water on the soil 2 days before, and 5 different times after, transplanting. Percent uptakes of the radionuclides to rice tops varied $3.4{\sim}13.7%,\;0.03{\sim}0.1%,\;0.6{\sim}1.5%,\;0.02{\sim}0.15%$, respectively, with application time. Among radionuclides, soil-to-plant transfer factors decreased, on the whole, in the order of $^{54}Mn>^{85}Sr>^{60}Co{\geq}^{137}Cs$, and among plant parts, in the order of straw > chaff > hulled seed. Transfer factors $(m^2/kg-dry)$ in hulled seed were, depending on application time, $1.2{\times}10^3{\sim}5.0{{\times}10^3\;for\;^{54}Mn,\;1.6{\times}10^5{\sim}2.6{\times}10^4\;for\;^{60}Co,\;1.1{\times}10^4{\sim}7.6{\times}10^4\;for\;^{85}Sr\;and\;5.2{\times}10^5{\sim}7.0{\times}10^4\;for\;^{137}Cs$. The highest factors of all the radionuclides in straw came from the application at 67 days after transplanting while those of $^{54}Mn,\;^{60}Co\;and\;^{85}Sr$ in hulled seed appeared at later applications. The data from this studv can be referred to in assessing the radiological impact of an accidental contamination during the rice growth.

• Journal of The Korean Society of Clinical Toxicology
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• v.9 no.2
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• pp.39-48
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• 2011

In mass casualty situation due to radiological accidents, it is important to start aggressive management with rapid triage decisions. External contamination needs immediate decontamination and internal contamination should be treated with special expertise and equipment to prevent the rapid uptake of radionuclides by target organs. Acute radiation syndrome shows a sequence of events that varies with the severity of the exposure. More severe exposures generally lead to more rapid onset of symptoms and severe clinical findings. After the massive exposure, various systems of the body reflect their severe damages that can lead to death within hours or up to several months. The disease progression has classically been divided into four stages: prodromal, latent, manifest illness, and recovery or death. Three characteristic clusters of symptoms including the hematopoietic syndrome, the gastrointestinal syndrome and the cerebrovascular syndrome are all associated with the acute radiation syndrome. The standard medical management of the patients with a potentially survivable radiation exposure includes good medical, surgical and supportive measures. Specific treatment with cytokines and bone marrow transplantation should be considered. The management of internal contamination is much the same as the treatment of poisoning. The standard decontamination should be applied to reduce uptake, and the chelating agents can be administered to enhance the clearance of radioisotopes. Radioactive iodine ($^{131}I$) as one of the nuclear fission products can increase the incidence of thyroid cancer in children. Potential benefit of potassium iodide prophylaxis is greater especially in neonates, infants and small children.

• The Korean Journal of Nuclear Medicine
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• v.36 no.1
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• pp.8-18
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• 2002

Early and accurate diagnosis of tumors using positron omission tomography (PET) has been the focus of considerable interest due to its high metastasis and mortality rates at late detection. PET radiopharmaceuticals-which exhibit a high tumor-to-background uptake ratio, and appropriate metabolic characteristics, and pharmacokinetics-are attractive tools for tumor imaging. Tumor imaging by these radiopharmaceuticals are based on metabolic and receptor imaging. The former is based on accelerated metabolism in tumor tissue compared to normal tissue and the rate roughly corresponding to the rate of growth of tumors. Radiopharmaceuticals for this purpose include radiolabeled sugars, amino acids, and nucleosides which detect increased glucose utilization, protein synthesis, and DNA synthesis, respectively. Tumor receptor imaging is based on the proliferation of tumor cells regulated by many hormones and growth factors, which bind to the corresponding receptors and exhibit the biological responses Radiopharmaceuticals used to image the tumor receptor systems may be ligands for the specific receptors and antibodies for the growth factor receptors. Some antitumor agents have been labeled with radionuclides and used to study in vivo biodistribution and pharmacokinetics in humans. This overview describes typical PET radiopharmaceuticals used for tumor imaging based on their uptake mechanisms.

• Korean Journal of Environmental Agriculture
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• v.2 no.1
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• pp.30-34
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• 1983

The present study was carried out to determine the effect of a radionuclide, cesium-137, in soybean, which is an element released usually from nuclear facilities. Soybean plants were grown on the pots treated with cesium-137 $0.5{\sim}60{\mu}Ci/1kg$ soil and the uptake, translocation and accumulation of the radiocesium in the plant parts were measured at different growth stage. The results are summarized as follows: 1) Visual toxic symptoms on the plants due to treatment of radioactive cesium were not observed up to $60{\mu}Ci/10Kg$ soil in a pot. 2) The uptake of cesium-137 in soybean plant was increased with increment of concentration applied, while the uptake of potassium was proportionally decreased, indicating to have an ion antagonistic relationship between them. 3) The absolute amounts of cesium-137 in the plants were gradually increased by the pod setting stage, but rather reduced at harvesting stage. The accumulation occurred more in the leaves and stems than the soybean seeds. 4) The rate of uptake was ranged from 0.069 to 0.005 with proportional decrease by increasing concentration applied and the rate of Cs-137 translocation from plants to seeds was averaged 38.6% in soybean plant. The concentration coefficient was 0.04 in the soybean seeds from the pots treated with $20{\mu}Ci$ of cesium-137 and decreased with increment of cesium-137 applied.

• Nuclear Engineering and Technology
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• v.25 no.3
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• pp.437-446
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• 1993

More realistic calculation models for evaluating man's annual intakes of radionuclides released from operating nuclear facilities were established. For the application of these models, the harvest years of food and feed crops consumed in the year of dose assessment and every year's average concentrations of a radionuclide in air and in water for the whole period of real operation had to be taken into account. KFOOD, an existing equilibrium food chain computer code for the Korean dose assessment, was modified according to the models. Sample runs of the modified code on the assumption of a constant release during 10 years' operation were made with three kinds of the input data files enabling the dose assessment in the improved method, the KFOOD method and another existing method, respectively, and the results were compared. Annual committed effective doses to Korean adult by intakes of Mn-54, Co-60, Sr-90, I-131 and Cs-137 calculated in the improved method were about 11, 2, 5, 60 and 3%, respectively, lower than the corresponding KFOOD dose. To the intakes of the radionuclides except Sr-90 evaluated in the improved method, foliar uptake contributed much more than root uptake did but, in the case of Sr-90, the result was opposite.

• Journal of Radiation Protection and Research
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• v.18 no.1
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• pp.9-24
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• 1993

The time-dependent radioecological model applicable to Korean environment has been developed in order to assess the radiological consequences following the short-term deposition of radionuclides in an accident of nuclear power plant. Time-dependent radioactivity concentrations in foodstuffs can be estimated by the model called 'KORFOOD' as well as time-dependent and time-integrated ingestion doses. Three kinds of critical radionuclides and thirteen kinds of foodstuffs were considered in this model. Dynamic variation of radioactivities were simulated by considering several effects such as deposition, weathering and washout, resuspension, root uptake, translocation, leaching, senescence, intake and excretion of soil by animals, intake and excretion of feedstuffs by animals, etc. The input data to the KORFOOD are the time of the year when the deposition occurs, the kinds of radionuclides and foodstuffs for estimation. The time-dependent specific activities in rice and the ingestion doses due to the consumption of all considered foodstuffs were calculated with deposition time using agricultural data-base in Kori region. In order to validate results of KORFOOD, the calculated results were compared with those by a leading German model, ECOSYS-87. The comparison of results shows good agreements within a factor of ten.

• Journal of Radiation Protection and Research
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• v.20 no.4
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• pp.245-253
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• 1995

The effects of a simultaneous application of KCl and lime on the root uptake of $^{54}Mn,\;^{60}Co,\;^{85}Sr\;and\;^{137}Cs$ by rice, soybean, Chinese cabbage and radish were investigated through 2 years' greenhouse experiments. At their early growth stages, a mixed solution of the radionuclides was applied to the water or soil surfaces of the culture boxes filled with an acidic loamy-sandy soil for the upper 20cm and $83g/m^2$ of fertilizer KCl and $200g/m^2$ of slake lime were applied to the surfaces. Distribution of radioactivities among plant parts and change in uptake pattern with plant species were not, on the whole, significantly affected by the application. It reduced effectively soil-to-plant transfer factors of $^{85}Sr\;and\;^{137}Cs$ for rice, of all for Chinese cabbage and of $^{54}Mn,\;^{60}Co,\;and\;^{137}Cs$ for radish without their growth inhibition. In rice, $^{85}Sr$ showed the highest decrease $({\sim}60%)$ while, in Chinese cabbage and radish, $^{54}Mn$ did $({\sim}80%)$. The exprimental results can become valuable reference data to establish countermeasures against a radioactive contamination of farm-land during plant growth.

• Journal of Radiation Protection and Research
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• v.37 no.2
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• pp.90-95
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• 2012

A radio-tracer experiment was performed in a greenhouse to investigate the effectiveness of the simultaneous application of K and Ca as a countermeasure for reducing the radiocaesium and radiostrontium uptake by rice. Paddy soil (loam of pH 6.5) in soil boxes was spiked with $^{137}Cs$ and $^{85}Sr$, and treated with K and Ca in the forms of KCl and $Ca(OH)_2$, respectively, at agrochemical grades before transplanting. For the seeds of the control plants, soil-to-plant transfer factors (TF, $m^2\;kg^{-1}-dry$) of $^{137}Cs$ and $^{85}Sr$ were $7.4{\times}10^{-5}$ and $2.1{\times}10^{-4}$, respectively, whereas the corresponding values for the straws were $2.6{\times}10^{-4}$ and $2.2{\times}10^{-2}$, respectively. The TF values of $^{137}Cs$ and $^{85}Sr$ kept decreasing as the level of the simultaneous application of K and Ca (K/Ca, $g\;m^{-2}$) increased up to 33.6/322 and 48.0/460, respectively. The maximum rate of the decrease was around 60% for both radionuclides. Nearly 60% reduction in the TF value of $^{85}Sr$ was observed even at the dosage of 33.6/322, which was considered the optimum dosage based on crop productivity as well as reduction in the radiocaesium and radiostrontium uptake by rice. The optimum dosage may depend on various factors so further experiments need to be made for many different conditions.

• The Korean Journal of Nuclear Medicine
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• v.20 no.1
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• pp.53-58
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• 1986

Thyroid scans using $Na^{131}I\;and\;^{99m}TcO_4^-$ in two (anterior and anterior oblique) projections were done simultaneously in 50 patients with single palpable nodule and in euthyroid state(nodular nontoxic goiter) and 20 normal subjects to evaluate the imaging ability of each radionuclide and the necessity of oblique view. In detection of a nodule as a cold or cool area, $^{99m}TcO_4^-$ was slightly superior to $^{131}I$(82 % to 78% with anterior view alone, 92% to 84% when oblique view is added in detectability), with addition of an oblique view, 5 more cold or cool area in $^{99m}Tc$ scan and 3 more $^{131}I$ scan were detected. In normal subjects $^{99m}TcO_4^-$ scan was significantly superior to $^{131}I$ scan(90% to 70%) in getting normal pattern of tracer uptake in the glands. For routine imaging study of the thyroid, $^{99m}Tc$ pertechnetate scan with multiple projection is considered to be a preferable method.

• Journal of Radiation Protection and Research
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• v.16 no.2
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• pp.55-65
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• 1991

Soil-to-plant transfer coefficients of Mn-54, Co-60, Zn-65, and Cs-137 were estimated for the edible parts of the rice, soybean, lettuce, carrot, and squash grown in different soils by radiotracer uptake experiments using pot cultures. The transfer coefficients of radionuclides were in the order of Zn-65 > Mn-54 > Cs-137 > Co-60 in most of the cases studied. The coefficients for soybean were roughly an order of magnitude higher than those for rice. Among vegetables, lettuce mostly showed the highest value and squash, the lowest. In the strongly acidic soils, transfer coefficients were much higher than in the moderately acidic soils. From the data obtained. crop-specific transfer coefficients of the four nuclides were proposed for the use in Korean food-chain radiation dose assessment.