• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4255-4261
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• 2012

The present study was conducted to evaluate radioimmunoimaging (RII) and in vivo distribution of mixed antibodies $^{99m}Tc$-EGFR-mAb and $^{99m}Tc$-CD44-mAb in nude mice bearing human lung adenocarcinoma xenografts. Single and mixed applications of the two radiolabeled monoclonal antibodies (mAbs) were compared. Direct labeling of $^{99m}Tc$ was applied to radiolabel the EGFR and CD44 mAbs. The properties of the radiolabeled antibodies were then characterized. RII and assessment of the distribution of the antibodies in nude mice bearing lung adenocarcinoma xenografts were achieved by applying separate and combined doses of $^{99m}Tc$-EGFR-mAb and $^{99m}Tc$-CD44-mAb. The labeling rates of $^{99m}Tc$ for EGFR-mAb and CD44-mAb were $91.5%{\pm}3.8%$ and $92.3%{\pm}4.1%$ respectively, with specific activities of 2.8 and $2.9MBq/{\mu}g$, respectively, and radiochemical purities (RCP) of 96.5% and 96.2%. The radioactivity uptake of the combined application of both radiolabeled antibodies was clearly higher than with a single application of either alone. The relative values of target-to-nontarget (T/NT) measured through the regional interest (ROI) technique were $5.59{\pm}0.42$ (mixed antibodies), $2.78{\pm}0.20$ ($^{99m}Tc$-EGFR-mAb), and $2.28{\pm}0.16$ ($^{99m}Tc$-CD44-mAb) in the RII. The body distribution of the radiolabeled antibodies and their imaging results were basically identical. Application of the mixed antibodies with $^{99m}Tc$-EGFR-mAb and $^{99m}Tc$-CD44-mAb can increase the radioactivity uptake of tumor tissue, leading to more ideal target-to-nontarget ratios, and therefore superior results.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.4
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• pp.331-341
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• 2016

To evaluate the physicochemical and radiological properties of raw materials and by-products in domestic distribution, about 220 samples with 16 species were prepared. We measured the energy spectrum and the chemical content, such as U, Th, and K, using a $LaBr_3$ scintillation detector and ED-XRF. In addition, HPGe detector was used to analyze the radioac-tivity of $^{234}Th$, $^{234}mPa$, and $^{214}Bi$ in uranium decay series and $^{228}Ac$, $^{212}Pb$, and $^{208}Tl$ in thorium decay series, and $^{40}K$. The correlation between characteristic variables, such as the count rate in several ROIs, chemical content, and radioactivity, was assessed to infer the radioactivity of natural radionuclides through a rapid screening method. Based on the results, a characteristic database for raw material and by-product in domestic distribution was established and it will provide useful information in the analysis procedure and improve the accuracy and reproducibility in the analysis of natural radionuclides.

• Korean Journal of Environmental Agriculture
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• v.15 no.1
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• pp.70-76
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• 1996

Absorption, distribution, excretion and metabolism of $^{14}C-{\alpha}-Endosulfan$[1,4,5,6,7,7-hexachloro-8,9,10-=trinorborn-5-en 2,3-ylenebismethylene]sulfite) were studied in male mouse(Balb/c) after single intraperitoneal treatment as the dose level of 7.5 mg/kg body weights. After treatment of $^{14}C-{\alpha}-endosulfan$, the radioactivity was rapidly excreted into the urine(63.9 %) within 4 days, thereafter the excretion ratio was constant. Radioactivity levels in the tissues was reached maximum 0.5 hr in heart, 2 hrs in liver and kidney after the treatment, then decreased with time. Endosulfan was metabolized to ${\beta}-endosulfan({\beta}-E)$, endosulfan ether(EE), endosulfan sulfate(ES), and endosulfan alcohol(EA). The main metabolites were EA(13.25 %) in liver and endosulfan hydroxyether(EHE)(19.37 %) in kidney. The urinary metabolites were EA(43.21 %), ES(4.78 %), ${\beta}-E$(7.21 %), EE(3.72 %) and EHE(18.04 %).

• Journal of Ginseng Research
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• v.12 no.1
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• pp.76-86
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• 1988

The rats were fed with 12% ethanol with and/or without 0. l% ginseng saponin instead of water for 6 days, and the acetaldehyde level of liver and serum, and [$NAD^+$]/ [NADH] and [$NADP^+$]/[NADPH] ratios of the liver were investigated. Acetaldehyde level of ethanol fed group (control) in liver and serum was much higher than not-ethanol fed group (normal), but that of ginseng saponin containing ethanol fed group (test) was only slightly higher than that of normal group. Decrease of [$NAD^+$] / (NADH) ratio of test group was also much greater than that of control group. Distribution of the radioactivity in hepatic lipids after the [l-$^{l4}C$]-ethanol feeding intraperitonealy was investigated 30 minutes later. It was found that total radioactivity of the hepatic lipids of test group was much lower than that of control group. Analysis of individual lipids such as phospholipids, cholesterol, fatty acid and triglycerides showed that the depression of phospholipid biosynthesis and increase of fatty acid and triglycerides caused by ethanol feeding were significantly recovered by the co-feeding of ginseng saponin.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1109-1116
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• 2019

It is essential to predict the radioactivity distribution around the reactor cooling system (RCS) during obligatory cyclic operation of AP-1000. A home-developed program CPA-AP1000 is upgraded to predict the response of activated corrosion products (ACPs) in the RCS. The program is written in MATLAB and it uses state of the art MCNP as a subroutine for flux calculations. A pair of cyclic power profiles were superimposed after initial full power operation. The effect of cyclic operation is noticed to be more prominent for in-core surfaces, followed by the primary coolant and out-of-core structures. The results have shown that specific activity trends of $^{56}Mn$ and $^{24}Na$ promptly follow the power variations, whereas, $^{59}Fe$, $^{58}Co$, $^{99}Mo$ and $^{60}Co$ exhibit a sluggish power-following response. The investigations pointed out that promptly power-following response of ACPs in the coolant is vital as an instant radioactivity source during leakage incidents. However, the ACPs with delayed power-following response in the out-of-core components are perceived to cause a long-term activity. The present results are found in good agreement with those for a reference PWR. The results are useful for source term monitoring and optimization of work procedures for an innovative reactor design.

• Journal of Radiation Protection and Research
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• v.22 no.4
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• pp.309-317
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• 1997

The measured radioactivity of gamma-emitting radionuclides in each radioactive waste drum using the non-destructive waste assay method is underestimated than real radioactivity in radioactive waste drum because the gamma-rays are attenuated within the medium. Therefore, the measured radioactivity should be corrected for the attenuation of gamma-rays. For the correction of the attenuation of gamma-rays, the attenuation correction method should be applied differently by considering the distribution and density of medium in radioactive wastes drum generated from nuclear power plants. In this study, the model drums were fabricated for simulating five types of radioactive waste drums generated from nuclear power plant and the optimum methods of the attenuation correction were experimentally determined to analyze the activity of radionuclides in the waste drum accurately using the segmented gamma scanning system. With the determination of the attenuation correction methods from the experimental results the transmission method and the average density method for the miscellaneous waste drum, the transmission method and the differential peak absorption method for the shielded miscellaneous waste drum were used to measure the density of medium in waste drums. Also, the average density method and the differential peak absorption method for the spent resin drum, the paraffin solidified drum, and the spent filter drum were used.

• Journal of Radiation Protection and Research
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• v.44 no.2
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• pp.64-71
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• 2019

Background: It is very difficult to distinguish between a radioactive contamination source and background radiation from natural radionuclides in the marine environment by means of online monitoring system. The objective of this study was to investigate a statistical process for triggering abnormal level of count rate data measured from our on-line seawater radioactivity monitoring. Materials and Methods: Count rate data sets in time series were collected from 9 monitoring posts. All of the count rate data were measured every 15 minutes from the region of interest (ROI) for $^{137}Cs$ ($E_{\gamma}=661.6keV$) on the gamma-ray energy spectrum. The Shewhart ($3{\sigma}$), CUSUM, and Bayesian S-R control chart methods were evaluated and the comparative analysis of determination methods for count rate data was carried out in terms of the false positive incidence rate. All statistical algorithms were developed using R Programming by the authors. Results and Discussion: The $3{\sigma}$, CUSUM, and S-R analyses resulted in the average false positive incidence rate of $0.164{\pm}0.047%$, $0.064{\pm}0.0367%$, and $0.030{\pm}0.018%$, respectively. The S-R method has a lower value than that of the $3{\sigma}$ and CUSUM method, because the Bayesian S-R method use the information to evaluate a posterior distribution, even though the CUSUM control chart accumulate information from recent data points. As the result of comparison between net count rate and gross count rate measured in time series all the year at a monitoring post using the $3{\sigma}$ control charts, the two methods resulted in the false positive incidence rate of 0.142% and 0.219%, respectively. Conclusion: Bayesian S-R and CUSUM control charts are better suited for on-line seawater radioactivity monitoring with an count rate data in time series than $3{\sigma}$ control chart. However, it requires a continuous increasing trend to differentiate between a false positive and actual radioactive contamination. For the determination of count rate, the net count method is better than the gross count method because of relatively a small variation in the data points.

• Journal of Mushroom
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• v.19 no.4
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• pp.294-299
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• 2021

The purpose of this study is to provide basic data on the safety of Poria cocos, a major Korean herbal medicine, and to establish tolerance levels for hazardous substances. Residual pesticides (321 types), heavy metals (7 types), radioactivity (3 types), and ash content were analyzed in 10 Poria cocos products distributed in Korea (5 domestic and 5 in China). Of the residual pesticides, cypermethrin was detected at 0.03 mg/kg in one domestic sample and was below the standard value. Of the heavy metals, the levels of Zn, Pb, Ni, Cu, Hg, and Cr were below the standard values in all samples. Hg was not detected in any sample. Cd was detected at 0.011 mg/kg in one Chinese sample. The radioactivity concentration was also below the MDA value in all P. cocos samples. The ash content was less than the standard value of 1.0% in all P. cocos samples. The findings indicate that P. cocos distributed in Korea is safe. However, because P. cocos is always exposed to harmful substances because of the nature of its cultivation in the soil, it seems necessary to establish systematic management standards for the entire production stage, such as cultivation, storage, and distribution.

• Economic and Environmental Geology
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• v.33 no.3
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• pp.195-204
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• 2000

order to investigate physical characteristics and element concentrations of sediments, coastal bottom sediments were collected at 20 stations in the vicinity of Youngkwang Nuclear Power Plant. After air drying of samples in the laboratory. article size distribution was examined by Master sizer (X-350F), radio-activity by HPGe ${\gamma}$-spectrphotometer, and element concentrations by ICP-AES and AAS. According to particle size analysis , sediments are mainly composed of silt fraction weith 23% of sand, 65% of silt and 12% of clay on average. Most sediments are derived from muddy environment that silt dominates with the characteristics of 5.3${\varsigma}$ mean particle size, poorly sorted, very fine skewed and lepto-kurtic. Only two sediments are well sorted with sandy silt owing to wind, winnowing action, tide and current andits complex reactions. Element concentrations in the coastal bottom sediments are relatively high at finer sediment and show significant relationship with grain size. Index of geoaccumulation by heavy metals at every sampling station is classified as practically unpolluted. The radioactivities of the sediments were measured for 15 isotope elements, and 2 elements of K-40 and Cs-137 were detected in most sediments. The K-40 is the natural nuclide and the artificial nuclide of Cs-137 was thought to be derived from the fallout of past nuclear weapon test. The results of correlation coefficient between grain size and radioactivity shows that the activity of Cs-137 significantly increases in finer grain.

• Nuclear Engineering and Technology
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• v.53 no.1
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• pp.244-252
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• 2021

Wind plays an important role in cases of unexpected radioactive pollutant dispersion, deciding distribution and concentration of the leaked substance. The accurate prediction of wind has been challenging in numerical weather prediction models, especially near the surface because of the complex interaction between turbulent flow and topographic effect. In this study, we investigated the characteristics of atmospheric dispersion of radioactive material (i.e. ¹³⁷Cs) according to the simulated boundary layer around the HANARO research nuclear reactor in Korea using the Weather Research and Forecasting (WRF)-Mesoscale Model Interface (MMIF)-California Puff (CALPUFF) model system. We examined the impacts of orographic drag on wind field, stability calculation methods, and planetary boundary layer parameterizations on the dispersion of radioactive material under a radioactive leaking scenario. We found that inclusion of the orographic drag effect in the WRF model improved the wind prediction most significantly over the complex terrain area, leading the model system to estimate the radioactive concentration near the reactor more conservatively. We also emphasized the importance of the stability calculation method and employing the skillful boundary layer parameterization to ensure more accurate low atmospheric conditions, in order to simulate more feasible spatial distribution of the radioactive dispersion in leaking scenarios.