• Journal of the Korean Society of Radiology
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• v.7 no.3
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• pp.213-219
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• 2013

Currently, about 35 cyclotrons have been operating in South Korea. Most of them are mainly used for the synthesis of radiopharmaceuticals such as $^{18}FDG$, which is a cancer tracer for nuclear medicine. Highly enriched $H_2{^{18}}O$ containing up to 98% of $^{18}O/O$ isotope ratio is used as the target for $^{18}F$ production. The price of the highly enriched $H_2{^{18}}O$ ranges 60~70 USD/g, and all of them have been imported from foreign country in spite of the very expensive price. The target (enriched $H_2{^{18}}O$) is non-radioactive before the proton beam irradiation. But, the post-irradiation target (used $H_2{^{18}}O$) must be managed following the National Radiation Safety Regulations, because it turns into radioactive by the radioactivation of the impurities within the target. Recently, nevertheless of the fast increasing amount of used $H_2{^{18}}O$ in accordance with the increasing number of nuclear medicine cases, any activation analysis on the used $H_2{^{18}}O$ have been conducted yet in Korea. In this research, activation analysis have been conducted to confirm the specific radioactivity(Bq/g) of each radioisotopes within the used $H_2{^{18}}O$. The analysis have been done on the 3 of 20g samples collected from the used $H_2{^{18}}O$ storages at different cyclotron centers. Based on the results, it was confirmed that the "used $H_2{^{18}}O$" contains gamma emitters such as $^{56}Co$, $^{57}Co$, $^{58}Co$, and $^{54}Mn$ as well as the considerable amount of beta emitter $^3H$. It was also confirmed that the only one sample contained over exemption level of gamma emitters while the specific activity of tritium was lower than the exemption level in all samples. The specific activity of radioisotopes were measured different levels in the samples depending on the elapsed time after irradiation. Further study on the activation of the "used $H_2{^{18}}O$" is definitely necessary, nevertheless the as-is results of this research must be useful in establishing a rational "used $H_2{^{18}}O$" management protocol.

• Journal of radiological science and technology
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• v.38 no.2
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• pp.163-170
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• 2015

The interest of the people in the radioactive contamination of the water has increased significantly and the study about analysis and management of radioactive materials are being actively conducted. And monitoring spots have been expanded to the range of public water as well as drinking water by publishing the rule of drinking water quality standards and examination in the Environmental Enforcement Ordinance No. 553 of Korea. In this study, US EPA was investigated as the foreign advanced cases and the way that is appropriate for the Korea was sought by analyzing investigate radionuclide, interval and management. As a result, in the selection part of investigate radionuclide, geological survey, status of nuclear power plants and the presence of the use of artificial radionuclides of the Korea should be investigated and additionally after the selection of a few radionuclides, the systems should be extended to cover all possible radionuclides by considering radioactive pollution levels in humans may be exposed due to the annual drinking water. In the part of the investigate interval, the concept(MCL, DL) should be set up for preventing concentration detection of above MCL and it needs to the maintenance and management. For example, when the concentration is more than MCL, it should be investigated on a quarterly and when the concentration is lower than MCL, it should be investigated to each different interval and management. And the US EPA divided the management area and make the roadmap for managing drinking water. The each classified area has been organized to match the state budget and labor force and the individual data have been managed effectively by HPGe, the NaI, TLD and so on.

• Journal of Korea Foresty Energy
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• v.19 no.2
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• pp.93-101
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• 2000

Wood of Robinia pseudoacacia and bark of Populus alba$\times$P. glandulosa, Fraxinus rhynchophylla and Ulmus davidiana var. japonica were collected and extracted with acetone-water(7:3, v/v) in glass jar to examine whether its bioactive compounds exist. The concentrated extracts were fractionated with hexane, chloroform, ethylacetate and water, and then freeze-dried for column chromatography and bioactive tests. The isolated compounds were sakuranetin-5-O-$\beta$-D-glucopyranoside from Populus alba $\times$Pl glandulosa, 4--ethyoxy-(+)-leucorobinetinidin frm R. pseudoacacia and fraxetion from F. rhynchophylla and were characterized by $^1H$ and$^{13}C $ NMR and positive FAB-MS. Decay-resistant activity was expressed by weight loss ratio and hyphae growth inhibition in the wood dust agar medium inoculated wood rot fungi. R. pseudoacacia showed best anti-decaying property in both test and its methanol untreated samples, indicating higher activity than methanol treated samples in hyphae grwoth test. In antioxidative test, $\alpha$-tocopherol, one of natural antioxidants, and BHT, one of synthetic antioxidants, were used as references to cmpare with the antioxidant activities of the extacted fractions. Ethylacetate fraction of F. rhynchophylla bark indicated the hightest activity in this test and all fractions of R. pseudiacacia extractives also indicated higher activities compared with the other fractions. In the isolated compounds, aesculetin isolated from F. rhynchophylla bark showed best activity and followed by robonetinidin from R. pseudoacaica.

• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1219-1224
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• 2005

Purpose : The prevalence of obesity in children and adolescents has been rising rapidly in Korea because of changes of diet and lifestyle. As with adults, obesity in children and adolescents can cause diabetes mellitus, hyperlipidemia, cardiovascular diseases and renal diseases. The aim of the present study is to examine the relation of obesity, glomerular filtration rate(GFR) and serum cystatin C concentration in children and adolescents. Methods : Data of 115 children and adolescents aged between 6 years and 20 years without clinical evidence of renal diseases were included in the study. From May 2004 to December 2004, blood samples were collected from children and adolescents who were seen at the Department of Pediatrics at Chungang University Yongsan Hospital. Obesity degrees and body mass indices(BMI) were measured, and GFRs were estimated from Schwartz's formula. Serum cystatin C was measured by particle enhanced nephelometric immunoassay using Behring Nephelometer II. Results : GFRs were significantly different between the obese group(BMI >95 percentile, $145.79{\pm}23.10mL/min$) and the non-obese group(BMI <95 percentile, $134.61{\pm}26.19mL/min$) divided by BMI (P=0.031). GFRs were not significantly different between the obese group(obesity degree >120 percent, $144.29{\pm}23.08mL/min$) and the non-obese group(obesity degree <120 percent, $134.54{\pm}26.57mL/min$) divided by obesity degree(P=0.051), but were significantly different between severe obese group (obesity degree >150 percent, $155.55{\pm}20.40mL/min$) and the non-obese group(P=0.004). GFRs were correlated positively with BMI($r^2=0.037$, P=0.039), but were not correlated significantly with obesity degree($r^2=0.030$, P=0.066). Serum cystatin C concentrations were not significantly different between the obese group and the non-obese group, divided by BMI as well as by obesity degree(P>0.05). Conclusion : Obesity may lead to an alteration of renal hemodynamics such as hyperfiltration, appropriate control and management for obesity is necessary.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.4
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• pp.503-510
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• 2012

Microwave radar can penetrate cloud cover regardless of weather conditions and can be used day and night. Especially a A ground-based polarimetric scatterometer operating at multiple frequencies can continuously monitor the crop conditions. We analyzed scattering characteristics of rice and soybean using pauli decomposition method. Surface scattering (${\alpha}$) is the dominant component over the entire stages for all bands and pauli decomposition value was the highest for L-band. Double bounce scattering (${\beta}$) and volume scattering (${\gamma}$) were approximately equal for C-band and volume scattering was higher than double bounce scattering for X-band in rice field. In soybean, double bounce scattering becomes higher than volume scattering during the R2 stage (DOY 224) and there was a significant difference between the two components after the R4 stage (DOY 242) for L-band. The maximum growth stage of soybean can also be detected using L-band double bounce scattering. The peak of double bounce effect coincides with the peak of growth biophysical variables on DOY 271. We found that pauli decomposition can provide insight on the relative magnitude of different scattering mechanisms during the rice and soybean growth cycle.

• Journal of Korean Society of Transportation
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• v.23 no.7 s.85
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• pp.165-179
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• 2005

The object of this study is a development of a stochastic user equilibrium transit assignment algorithm for multiple user classes considering stochastic characteristics and heterogeneous attributes of passengers. The existing transit assignment algorithms have limits to attain realistic results because they assume a characteristic of passengers to be equal. Although one group with transit information and the other group without it have different trip patterns, the past studies could not explain the differences. For overcoming the problems, we use following methods. First, we apply a stochastic transit assignment model to obtain the difference of the perceived travel cost between passengers and apply a multiple user class assignment model to obtain the heterogeneous qualify of groups to get realistic results. Second, we assume that person trips have influence on the travel cost function in the development of model. Third, we use a C-logit model for solving IIA(independence of irrelevant alternatives) problems. According to repetition assigned trips and equivalent path cost have difference by each group and each path. The result comes close to stochastic user equilibrium and converging speed is very fast. The algorithm of this study is expected to make good use of evaluation tools in the transit policies by applying heterogeneous attributes and OD data.

• Korean Journal of Food Science and Technology
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• v.43 no.5
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• pp.564-569
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• 2011

This study qualitatively and quantitatively analyzed various carotenoids, L-ascorbic acid, and tocopherol and their anti-oxidant properties from four varieties (Special, Chelsea, Cupra, and Fiesta) and three different color stages [green (GP), yellow (YP) and red (RP)] of paprika harvested in Korea. Seven carotenoids were identified, mainly lutein in GP (Special: 4.65${\pm}$0.84 mg/kg fresh weight (fw)) and YP (Fiesta: 5.19${\pm}$0.05 mg/kg fw), and capsorubin (3.16${\pm}$0.35 mg/kg fw) and capsanthin (53.70${\pm}$6.23 mg/kg fw) in Special of RP. RP was the highest in total carotenoids, L-ascorbic acid, and ${\alpha}$-tocopherol contents, while GP was the highest in ${\gamma}$-tocopherol content. RP showed the strongest antioxidant activity ($IC_{50}$=62.40${\pm}$0.03 ${\mu}g/mL$ in an ABTS assay and 182.77${\pm}$31.74 ${\mu}g/mL$ in a DPPH assay). Paprika in different color stages has many phytochemicals even though they have different kinds of carotenoids. Therefore, dietary intake of paprika may be helpful for improving human health.

• Journal of Nutrition and Health
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• v.40 no.7
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• pp.593-600
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• 2007

Recent studies described the ${\varepsilon}4$ allele of apoE confers a two-to fourfold increased risk for late-onset Alzheimer#s disease (LOAD), but LOAD pathology does not all fit neatly around apo E. Therefore, the goal of this study was to find the association between Alzheimer and apo E4 genotype in the 107 elderly between 50 to 64 years old who visited to FHWC of Sungshin Women#s University. We conducted the questionnaire survey (general & 24 hr dietary recall), anthropometerics (BP, waist & BMI) and blood biochemistry (FBS & lipid profiles). LDL-c and HOMA-IR were calculated by Friedwald#s and Matthew#s formulas. The apo E genotyping was performed by PCR-RFLP method and subjects were divided into three allele groups (${\varepsilon}3$; wild, ${\varepsilon}2$ & ${\varepsilon}4;$ mutants). The apo E allele frequencies were 7.0% for the ${\varepsilon}2$, 83.6% for the ${\varepsilon}3$ and 9.3% for the ${\varepsilon}4$. In comparison with biochemistry characteristics by apo E genotype, FBS was significantly higher in ${\varepsilon}4(129.2{\pm}6.8)$ than that in the others (${\varepsilon}2$: $117{\pm}7.4$, ${\varepsilon}3$: $107.3{\pm}2.2)$ (p<0.01). More than forty percents of ${\varepsilon}4$ group shown the dyslipidemia [high TG (>150mg/dl) & low HDL (<40 mg/dl:male or <50 mg/dl: female)]. The cytokines levels such as IL-1 ${\beta}$, IL-6 and $TNF-{\alpha}$ were not different among three apoE alleles. After the adjusting sex, age & dietary fiber, LDL-c level was siginificantly higher in ${\varepsilon}4$ ($108.3{\pm}7.7$) than that in ${\varepsilon}2$ ($100.4{\pm}8.4$) (p<0.05). According to food intake and the recipe on the basis of 24 hr dietary recall, the elder]y with ${\varepsilon}4$ allele took higher intake frequency of the light -colored vegetable (radish, onion & cabbage) and pan-fried foods (sauteed beef and vegetables, stir-fried vienna with vegetables) than the others. We knew that the elderly with ${\varepsilon}4$ allele had been restricted the calories intakes with high dietary fiber (33.6+2.5 g/d) to maintain the normal level of FBS and LDL-c. On next study, the prevalence of Alzheimer#s disease in this population who has ${\varepsilon}4$ allele on the condition of calories restriction will be continually follow-up.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.3
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• pp.189-203
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• 2008

The physical and chemical properties of radioactive waste drums, which have been temporarily stored on site, should be characterized before their shipment to a disposal facility in order to prove that the properties meet the acceptance guideline. The investigation of NDT(Nondestructive Test) method was figured out that the contents in drum, the quantitative analysis of free standing water and void fraction can be examined with X-ray NDT techniques. This paper describes the characteristics of X-ray NDT such as its principles, the considerations for selection of X-ray system, etc. And then, the waste drum characteristics such as drum type and dimension, contents in drum, etc. were examined, which are necessary to estimate the optimal X-ray energy for NDT of a drum. The estimation results were that: $(R)\acute{A}$ the proper X-ray energy is under 3 MeV to test the drums of 320 ${\beta}\S$ and less; $(R)\ddot{E}$ both X-ray systems of 450 keV and/or 3 MeV might be needed considering the economical efficiency and the realization. The number of drums that can be tested with 450 keV and 3 MeV X-ray system was figured out as 42,327 and 18,105 drums (based on storage of 2006. 12), respectively. Four testing scenarios were derived considering equipment procurement method, outsourcing or not, etc. The economical and feasibility assessment for the scenarios was resulted in that an optimal scenario is dependent on the acceptance guide line, the waste generator's policy on the waste treatment and the delivery to a disposal facility, etc. For example, it might be desirable that a waste generator purchases two 450 keV mobile system to examine the drums containing low density waste, and that outsourcing examination for the high density drums, if all NDT items such as quantitative analysis for 'free standing water' and 'void fraction', and confirmation of contents in drum have to be characterized. However, one 450 keV mobile system seems to be required to test only the contents in 13,000 drums per year.

• Microbiology and Biotechnology Letters
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• v.45 no.2
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• pp.101-109
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• 2017

This study investigated the effect of the dichloromethane fraction form Katsuwonus pelamis heart on anti-inflammatory responses in lipopolysaccharide-stimulated RAW 264.7 cells and mouse models. Ethanol extract was partitioned with dichloromethane, ethyl acetate, butanol, and water. Among the fractions, the dichloromethane fraction showed a significant decrease in nitric oxide (NO) and pro-inflammatory cytokines [interleukin (IL)-6, $IL-1{\beta}$, and tumor necrosis $factor-{\alpha}$] production compared to ethanol extract. The dichloromethane fraction attenuated the expression of inducible nitric oxide synthase and nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) p65 proteins in a dose-dependent manner. In addition, the expression of phosphorylation of mitogen-activated protein kinases (MAPKs) was also inhibited by the dichloromethane fraction. Moreover, the administration of 10, 50, and 250 mg/kg body weight-dose dependently inhibited the formation of edema by croton-oil and the application of dichloromethane (2 mg/ear) significantly reduced epidermal and dermal thickness and the infiltrated mast cell numbers. Therefore, the dichloromethane fraction exhibited an anti-inflammation effect by inhibiting $NF-{\kappa}B$ and MAPK signaling activation in macrophages.