• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.8
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• pp.3572-3578
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• 2011

In Positron Emission Tomography Computed Tomography, Standardized Uptake Value(SUV)is most generally used to discern tumors. However, SUV may be influenced other factors. In this study, experiment was conducted distrotion in image and change in SUV according to substance with GEMINI TF PET/CT of Philips.. SUV for materials resulted in 1.8 for stainless, 1.4 for stent, 2.4 for iodine contrast medium, 2.6 for Barium Sulfate, 1.6 for Gypsum, and 1.4 for paraffin respectively. The distortion of image was remarkable for the iodine contrast medium and Barium Sulfate. For the barium sulfate, the higher the density, the larger the distrotion of the images. As a result of test, it appeared that the metallic substance whose atomic number is low and contrast medium whose concentration is low didn't affect the distortion in image and the change in SUV. However, it tis necessary to minimize distortion in image and change in SUV, by removing the metallic substance and checking if there are contrast mdeium or before examination.

• Journal of Korean Society of Rural Planning
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• v.22 no.4
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• pp.71-80
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• 2016

Meanwhile, reference evapotranspiration(ET0) is important information for agricultural management including irrigation planning and drought assessment, the database of reference evapotranspiration for future periods was rarely constructed especially at districts unit over the country. The Coupled Model Intercomparison Project Phase 5 (CMIP5) provides several meteorological data such as precipitation, average temperature, humidity, wind speed, and radiation for long-term future period at daily time-scale. This study aimed to build a database for reference evapotranspiration using the climate forecasts at high resolution (the outputs of HadGEM3-RA provided by Korea Meteorological Administration (KMA)). To estimate reference evapotranspiration, we implemented four different models such as FAO Modified Penman, FAO Penman-Monteith, FAO Blaney-Criddle, and Thornthwaite. The suggested database system has an open architecture so that user could add other models into the database. The database contains 5,050 regions' data for each four models and four Representative Concentration Pathways (RCP) climate change scenarios. The developed database system provides selecting features by which the database users could extract specific region and period data.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.15 no.1
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• pp.45-63
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• 2017

The oldest commercial reactor in South Korea, Kori-1 Nuclear Power Plant (NPP), will be shut down in 2017. Proper treatment for decommissioning wastes is one of the key factors to decommission a plant successfully. Particularly important is the recycling of clearance level or very low level radioactively contaminated metallic wastes, which contributes to waste minimization and the reduction of disposal volume. The aim of this study is to introduce a conceptual design of a recycle system and to evaluate the doses incurred through defined work flows. The various architecture diagrams were organized to define operational procedures and tasks. Potential exposure scenarios were selected in accordance with the recycle system, and the doses were evaluated with the RESRAD-RECYCLE computer code. By using this tool, the important scenarios and radionuclides as well as impacts of radionuclide characteristics and partitioning factors are analyzed. Moreover, dose analysis can be used to provide information on the necessary decontamination, radiation protection process, and allowable concentration limits for exposure scenarios.

• 한국연소학회:학술대회논문집
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• 2002.06a
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• pp.85-94
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• 2002

Computational flow dynamics(CFD) has been frequently applied to the waste incinerators to understand the flow performance for various design and operating parameters. Though it needs many simplifications and complicated flow models, the reasonability of its results is not fully evaluated. For example, the inlet condition is calculated from an arbitrarily assumed properties of combustion gas release from the waste bed, since the combustion in the bed is difficult to be predicted. In this study, the computational modeling and calculation procedures of CFD for the grate type waste incinerator were evaluated using comparative simulations. Though the assumption method on the generation of the combustion gas directly affected the temperature and gas species concentrations, the overall flow pattern was dominated by the secondary air jets. The gaseous reaction could be included by assuming the release of the products of incomplete combusion from the bed. However, the reaction effficiency cannot not be directly evaluated from the species concentration, since it is not possible to simulate the actual co-existence of fuel rich or oxygen rich puffs over the bed. In predicting the turbulence, the higher order model, such as Reynolds stress model, gave difference shape of local recirculation zones, but similar results was acquired from the standard $k-{\varepsilon}$ model. Introducing radiation model was required for accurate temperature prediction, but it also caused heat imbalance due to the fixed temperature of the inlet, i.e. the waste bed. Thus, the computational modeling procedures on incinerators and the analysis of the predicted results should be progressed carefully. Though not validated experimentally, current simulation method is capable of comparative evaluation on the flow-related parameters such as the furnace shape and secondary air injection using identical inlet conditions. Quantitative analysis using measures of the residence time and mixing is essential to compare the flow performance efficiently.

• Nutrition Research and Practice
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• v.10 no.4
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• pp.393-397
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• 2016

BACKGROUND/OBJECFTIVES: Artemisinin, a natural product isolated from Gaeddongssuk (artemisia annua L.) and its main active derivative, dihydroartemisinin (DHA), have long been used as antimalarial drugs. Recent studies reported that artemisinin is efficacious for curing diseases, including cancers, and for improving the immune system. Many researchers have shown the therapeutic effects of artemisinin on tumors such as breast cancer, liver cancer and kidney cancer, but there is still insufficient data regarding glioblastoma (GBM). Glioblastoma accounts for 12-15% of brain cancer, and the median survival is less than a year, despite medical treatments such as surgery, radiation therapy, and chemotherapy. In this study, we investigated the anti-cancer effects of DHA and transferrin against glioblastoma (glioblastoma multiforme, GBM). MATERIALS/METHODS: This study was performed through in vitro experiments using C6 cells. The toxicity dependence of DHA and transferrin (TF) on time and concentration was analyzed by MTT assay and cell cycle assay. Observations of cellular morphology were recorded with an optical microscope and color digital camera. The anti-cancer mechanism of DHA and TF against GBM were studied by flow cytometry with Annexin V and caspase 3/7. RESULTS: MTT assay revealed that TF enhanced the cytotoxicity of DHA against C6 cells. An Annexin V immune-precipitation assay showed that the percentages of apoptosis of cells treated with TF, DHA alone, DHA in combination with TF, and the control group were $7.15{\pm}4.15%$, $34.3{\pm}5.15%$, $66.42{\pm}5.98%$, and $1.2{\pm}0.15%$, respectively. The results of the Annexin V assay were consistent with those of the MTT assay. DHA induced apoptosis in C6 cells through DNA damage, and TF enhanced the effects of DHA. CONCLUSION: The results of this study demonstrated that DHA, the derivative of the active ingredient in Gaeddongssuk, is effective against GBM, apparently via inhibition of cancer cell proliferation by a pharmacological effect. The role of transferrin as an allosteric activator in the GBM therapeutic efficacy of DHA was also confirmed.

• Clinical and Experimental Reproductive Medicine
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• v.16 no.2
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• pp.131-138
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• 1989

The present study was designed to develop a new method for the determination of estrogen receptor in porcine uterus using frozen sections. Cryostat sections were incubated with $^3H$-estradiol($^3H$-$E_2$) in the presence or absence of diethylstilbestrol(DES) and the radioactivity of 3H-E2 bound to estrogen receptor(ER) was detected. The level of specific estrogen receptor was determined by Scatchard analysis. The highest ratio of specific binding against total binding was achieved in 3 sec. tions(5mm x 5mm) which was corresponded to lOO${\mu}$/ml protein concentration. Optimal binding was obtained during incubation with $^3H$-$E_2$ for 30 minutes at 23$^{\circ}C$ after treatment of sections with acetone for 20 seconds. Three time-washing of sections was proved to be appropriate for the removal of unbound 3H-E2. 200-fold molar excess of DES was substituted for the binding of $^3H$-$E_2$ to ER sufficiently(binding efficiency of 54.8%). ER was saturated with 4nM of $^3H$-$E_2$ and its dissociation constant was 0.1nM. ER assay using frozen sections(Histological radioreceptor assay, HRRA) was significantly correlated with radioreceptor assay for estradiol(RRA, 0.976 , p

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.206-219
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• 2008

The purpose of this study is to evaluate concentrations of carbonyl compounds during summer season in Seoul metropolitan area. The air samples were collected at 7 sites in this area from June 2001 to June 2003. The carbonyl compounds were analyzed by DNPH/HPLC method. The analytical method applied in this study showed good repeatability, linearity, and sensitivity. The most abundant carbonyl was formaldehyde (average 4.48 ppb), and followed by acetone, acetaldehyde, methyl ethyl ketone, butyraldehyde, propionaldehyde and benzaldehyde, respectively. Concentrations of carbonyl compounds in June were higher than those in August. There was not only higher solar radiation but also higher ozone concentration in June than in August. As a result o photochemical reactions, carbonyl compounds from both primary and secondary sources are likely to contribute to the formation of ozone. The contributions to photochemical ozone creation of two carbonyl compounds such as formaldehyde and acetaldehyde were estimated to be about 70%. Ratios of formaldehyde to acetaldehyde in this study ranged from 1.13 to 4.26, which are generally equivalent levels to those of other urban areas in domestic and foreign countries.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.3
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• pp.225-236
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• 2000

Diurnal variations of wind field and pollutant dispersion over the Yosu area under the insolation conditions of summer and winter were investigated by using the Regional Atmospheric Modeling System (RAMS). Initially, horizontally homogeneous wind field were assumed on the basis of sounding data at the Kwangju upper-air station for days whose morning wind speeds were below 2m/s. In these days, the sea breeze prevailed in summer while the land breeze lasted for a few hours in the morning; the effect of synoptic winds was strong in winter with some inclusion of wind variations owing to the interaction between sea and land. The predicted wind direction at the location of the Yosu weather station captured an important change of the sea-land breeze of the observed one. The predicted wind speed and the air temperature agreed with observed ones in a reasonable range. In the morning, both in summer and winter, winds around the source location were diverged and became weak between the mountainous area to the southeast and the Kwangyang Bay to the north. Winds, however, accelerated while blowing to the east and south and blowing on the mountainous area. Complicated wind fields resulted in high pollutant concentrations at almost all receptors considered. These high concentrations in the morning were even comparable to the ISCST3 calculations with the worst-case and typical meteorological conditions designated by USEPA(1996). On the other hand, in the afternoon, the wind field was rather uniform even in the mountainous area with development of mixing layer and the concentration distributions being close to the Gaussian distributions.

• Microbiology and Biotechnology Letters
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• v.45 no.3
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• pp.271-275
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• 2017

The expression of Deinococcus radiodurans dr1558 and pprM genes was examined for enhanced lysine production in recombinant Corynebacterium glutamicum. These genes are known to confer high tolerance to pH and osmotic shock in Escherichia coli. D. radiodurans dr1558 and pprM genes were expressed in C. glutamicum by using 6 synthetic promoters of different strengths, to evaluate the effect of expression efficiency on lysine production. Recombinant C. glutamicum expressing DR1558 under the L26 and I64 promoters showed higher lysine production than that expressing DR1558 under other promoters. Similarly, recombinant C. glutamicum expressing PprM under same promoters (L26 and I64) showed a higher increase in lysine production compared to that expressing PprM under other promoters. In the absence of $CaCO_3$ in the medium, the expression of DR1558 or PprM also increased lysine concentration in C. glutamicum depending on the promoter used. Together, these results suggest that genes involved in radiation tolerance in D. radiodurans can be used to enhance production of amino acids and their derivatives.

• Proceedings of the Korean Vacuum Society Conference
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• 1995.02a
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• pp.36-36
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• 1995

The cubic (zinc blende) CdSe eppilayers were grown on GaAs(100) substrates by electron beam (e-beam) evapporation technique. X-ray scans with copper $K\alpha$ radiation indicate that the CdSe eppilayers are zinc blende. The lattice pparameter obtained from the (400) reflection is 6.077$\AA$, which is in excellent agreement with the value repported in the literature for zinc blende CdSe. The orientation of as-grown CdSe eppilayer is determined by electron channeling ppatterns(ECpp). The crystallinity of heteroeppitaxial CdSe layers were investigated based on the double crystal x-ray rocking curve(DCRC). The deppendence of the rocking curve width on layer thickness was studied. The FWHM(full width at half maximum) of CdSe eppilayers grown on GaAs(100) substrates is decreasing with increasing eppilayer thickness. The carrier concentration and mobility of the as-grown eppilayers deduced Hall data by van der ppauw method, are about 7$\times$1017 cm-3 and 2$\times$102 $\textrm{cm}^2$ / sec at room tempperature, resppectively. The energy gapp was determinded from the pphotocurrent sppectrum. In pphotocurrent sppectrum of a 1-${\mu}{\textrm}{m}$-thick CdSe eppilayer at 30K, the ppeak at 1.746 eV is due to the free exciton of cubic CdSe. In summary, We have shown that eppilayers of zinc blende CdSe can be grown on GaAs(100) substrates by e-beam, desppite the large mismatch between eppilayer and substrate, as well as the natural ppreference for CdSe to form in the wurtzite structure.