• Korean Journal of Remote Sensing
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• v.32 no.2
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• pp.119-131
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• 2016

Descriptions are provided of the automated aerosol-type classification and mass concentration calculation algorithm for real-time data processing and aerosol products in Korea Aerosol Lidar Observation Network (KALION, http://www.kalion.kr). The KALION algorithm provides aerosol-cloud classification and three aerosol types (clean continental, dust, and polluted continental/urban pollution aerosols). It also generates vertically resolved distributions of aerosol extinction coefficient and mass concentration. An extinction-to-backscatter ratio (lidar ratio) of 63.31 sr and aerosol mass extinction efficiency of $3.36m^2g^{-1}$ ($1.39m^2g^{-1}$ for dust), determined from co-located sky radiometer and $PM_{10}$ mass concentration measurements in Seoul from June 2006 to December 2015, are deployed in the algorithm. To assess the robustness of the algorithm, we investigate the pollution and dust events in Seoul on 28-30 March, 2015. The aerosol-type identification, especially for dust particles, is agreed with the official Asian dust report by Korean Meteorological Administration. The lidar-derived mass concentrations also well match with $PM_{10}$ mass concentrations. Mean bias difference between $PM_{10}$ and lidar-derived mass concentrations estimated from June 2006 to December 2015 in Seoul is about $3{\mu}g\;m^{-3}$. Lidar ratio and aerosol mass extinction efficiency for each aerosol types will be developed and implemented into the KALION algorithm. More products, such as ice and water-droplet cloud discrimination, cloud base height, and boundary layer height will be produced by the KALION algorithm.

• Korean Journal of Remote Sensing
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• v.34 no.2_1
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• pp.295-300
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• 2018

Net radiation is the total amount of radiation energy used as a heat flux for the Earth's energy cycle, and net radiation from the surface is an important factor in areas such as hydrology, climate, meteorological studies and agriculture. It is very important to monitoring the net radiation through remote sensing to be able to understand the trend of heat island and urbanization phenomenon. However, net radiation estimation using only remote sensing data is generally causes difference in accuracy depending on cloud. Therefore, in this paper, we retrieved and monitored high resolution surface net radiation at 1 hour interval in Eunpyeong New Town where urbanization using Communication, Ocean and Meteorological Satellite (COMS), Landsat-8 satellite and Computational Fluid Dynamics (CFD) model data reflecting the difference in building height. We compared the observed and estimated net radiation at the flux tower. As a result, estimated net radiation was similar trend to the observed net radiation as a whole and it had the accuracy of RMSE $54.29Wm^{-2}$ and Bias $27.42Wm^{-2}$. In addition, the calculated net radiation showed well the meteorological conditions such as precipitation, and showed the characteristics of net radiation for the vegetation and artificial area in the spatial distribution.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.329-343
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• 2001

The deep environment and geochemical evolution of the Bugok geothennal waters, located in the Kyeongnam Province, was re-interpreted based on the hydrochemical and isotopic data published by Yun et al. (1998). The geothermal waters of the Bugok area is geochemically divided into three groups; Geothennal water I, II and III groups. Groups I and II are geochemically similar; high temperature (55.2-77.2$^{\circ}$C) and chemically belonging to Na-S04 types. However, pH and Eh values are a little different each other and Group II water is highly enriched in S04 compared to Group I water. Group III water, occurring from peripheral sites of the central part of the geothennal waters, shows temperature range of 29.3 to 47.0$^{\circ}$C and belongs to $Na-HCO_3-S0_4$ types. The deep environment and geochemical evolution of the Bugok geothennal waters, showing the diversity of geochemistry, can be interpreted as follows; I) Descending to great depth of meteoric waters that originated at high elevation and reacting with sediments and/or granites in depth. The $S0_4$ concentration of the waters has been increased by the dissolution of sulfate minerals in sediments. 2) During the continuous descending, the waters has met with the reduction environment, producing the $H_2S$ gas due to sulfate reduction. The waters has been heated up to 130$^{\circ}$C and the extent of water-rock reaction was increased. At this point, pH of waters are increased, S04 concentration decreased and calcite precipitated, therefore, the waters show the $Na-S0_4$ type. 3) Ascending of the geothennal waters along the flow path of fluids and mixing with less-deeply circulated waters. The $S0_4$ concentration is re-increased due to the oxidation of $H_2S$ gas and/or sulfide minerals in sediments. During continuous ascending, these geothennal waters are mixed with shallow groundwater.

• The Korean Journal of Pesticide Science
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• v.19 no.4
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• pp.354-360
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• 2015

In recent years, Allium victorialis has been extensively used as a pharmacological agent for various diseases in the form of anti-arteriosclerotic, anti-diabetic and anti-cancer. Allium victorialis is severely affected by various fungal diseases since it naturally grow in the shady and humid environments in Korea. In this case, different types of fungicides are applied to control the fungal diseases in Allium victorialis. The present study was aimed to determine the residual characteristics of two fungicides namely tebuconazole and fludioxonil on Allium victorialis. For this study, the fungicides were drenched soil on Allium victorialis in the cultivation area Pyeongchang by the standard (two thousand fold) and double (thousand fold) dilutions. At the end of $15^{th}$, $30^{th}$ and $40^{th}$ days samples were collected for residue analysis. Residues of tebuconazole and fludioxonil were analyzed using GC/NPD (Gas Chromatography/Nitrogen Phosphorus Detector) and their recovery were found to be 108.8~119.5% and 91.3~104.8%, respectively. The method of limits of quantification for both fungicides was $0.01mg\;kg^{-1}$. Further, the results of this study shows that the residue levels of both fungicides on Allium victorialis were <$0.01{\sim}0.12mg\;kg^{-1}$ and $0.01{\sim}0.09mg\;kg^{-1}$ and their % ADI (% Acceptable Daily Intake) were 17.44% and 25.75%, respectively. Based on the results obtained in this study, we suggest that the residue levels of both of the fungicides on Allium victorialis are safe and these fungicides can also be used to control fungal diseases in Allium victorialis.

• Clinical and Experimental Pediatrics
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• v.48 no.6
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• pp.624-633
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• 2005

Purpose : This study analyzed the expression of HLA-DR and DQ genotypes and anti-thyroid autoantibodies[anti-thyroid peroxidase(TPO) and anti-thyroglobulin(TG) antibodies] in Korean patients with type 1 diabetes(T1DM) to investigate the susceptible HLA alleles to T1DM in Korea and the prevalence of thyroid autoantibodies and their significance for the development of thyroid disorders. Methods : A total of 59 Korean patients with type 1 diabetes[26 males, median age 13.7 years(range 5.7-29.9 years), diabetes duration 7.6 years(-1.7-22.5 years)] were enrolled in this study, and 200 healthy Koreans without a family history of diabetes were selected as a normal control for the comparison of HLA genotypes. Seventeen patients with anti-TPO or anti-TG were followed [median duration 3.96 years(1 day-10.7 years)] with measurement of anti-TPO, anti-TG, $T_3$, $T_4$ or free $T_4$, TSH levels and physical examinations. HLA-DR and DQ genotyping were done by PCR-SSO, PCR-SSCP, PCR-RFLP and PCR-SSP methods. Results : HLA analysis showed higher frequencies of HLA-DRB1*0301, *090102 and DQB1*0201, *030302 alleles, DRB1*0301/*090102, *090102/*090102 and DQB1 *0201/*030302, *030302/*030302, *0201/ *0302 genotypes in T1DM patients compared to controls(Pc<0.05). Fifteen(25.4 percent) had anti-TPO antibody, 12(20.3 percent) had anti-TG, 17(28.8 percent) had either autoantibody and 10(16.9 percent) had both autoantibodies. No clinical or subclinical hypothyroidism developed during follow-up after the first detection of anti-thyroid autoantibody. There was no significant correlation between thyroid autoimmunity and gender, onset age of T1DM, and diabetes duration, respectively(P>0.05). Conclusion : We thought this unique HLA-DR, DQ allele distribution might be an important factor for the low incidence of T1DM in Korea. And a high prevalence of thyroid autoantibodies in these populations suggests examinations of thyroid antibodies should be performed regularly. Optimal age for the initial screening and the frequency of re-screening for associated thyroid autoimmune diseases in T1DM remains to be determined through prospective follow-up.

• Clinical and Experimental Pediatrics
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• v.45 no.6
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• pp.764-772
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• 2002

Purpose : Obesity is closely related to insulin resistance, compensatory hyperinsulinemia and dyslipidemia in adults. We identified the effect of obesity measured by BMI and insulin resistance on dyslipidemia in children and adolescents. Methods : The fasting serum insulin, glucose, total cholesterol, triglyceride, HDL- and LDL-cholesterol were measured and insulin resistance(HOMA-IR) was calculated in 35 children with simple obesity(age :$10.6{\pm}2.8$ years; male 20, female 15; BMI : $27.1{\pm}5.4kg/m^2$). Results : The hypertriglyceridemia(37%), hyperinsulinemia(54%) and HDL-hypocholesterolemia(5.7%) were observed. HOMA-IR was well expressed by fasting insulin. As BMI increased, there was a statistically significant increase in insulin resistance and insulin level in both sexes. BMI was not related with lipid profile in both sexes. Triglyceride was correlated with only insulin level and insulin resistance index in boys. In girls, there was no correlation between triglyceride, HDL-cholesterol and insulin(insulin resistance). Conclusion : These results suggest that hypertriglyceridemia was dependent on insulin resistance in pre-adult males. Monitoring of insulin resistance and those risk factors known to become a part of insulin resistance syndrome should become part of routine medical care for obese children.

• Clinical and Experimental Pediatrics
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• v.45 no.6
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• pp.754-763
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• 2002

Purpose : The incidence of type 2 diabetes in children and adolescents has been reported to increase recently. The aim of this study is to investigate the clinical features of type 2 diabetes developing during childhood and adolescent period. Methods : The medical records of 33 patients with type 2 diabetes were reviewed. We analysed clinical manifestations, demographic data, and modes and responses of treatment. Results : Age at diagnosis was $13.4{\pm}1.8$ years. Seventy percent of patients revealed pubertal signs at diagnosis. Half of the patients had BMI more than $25kg/m^2$. Seventy-three percent of patients had family history of type 2 diabetes. Acanthosis nigricans were found in 18% of patients. Nineteen(57.6%) patients were diagnosed incidentally by random urine or blood glucose test without any typical diabetic symptom or sign. The modes of therapy to control hyperglycemia were insulin alone(75.8%), oral hypoglycemic agents alone(9.1%), insulin and oral hypoglycemia agents(9.1%), and only diet with exercise(6%). At the time of investigation, 45.5% of patients were not using insulin. The typical diabetic symptoms at diagnosis were more prevalent in patients who required insulin for more than two years than patients who did not(P<0.05). Conclusion : The development of type 2 diabetes in children and adolescents is possibly related to puberty, obesity, family history, and defects in insulin secretion rather than insulin resistance. Many children and adolescents with type 2 diabetes required insulin initially and some of them could discontinue. More than half of the patients were diagnosed as diabetes without any typical symptom or sign, which might be one of the predictive factors of the prolonged insulin requirement.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.803-810
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• 2003

Purpose : The purpose of this study was to evaluate the factors affecting the final adult height and total height gain in idiopathic and organic growth hormone deficient(GHD) children after growth hormone(GH) treatment. Methods : Thirteen patients with idiopathic GHD and 22 patients with organic GHD who had been treated with GH and attained adult final height were included in this study. Factors which could affect the final adult height(FAH) and total height gain, were evaluated. Results : Height SDS(standard deviation score) at initial GH treatment in idiopathic GHD was significantly shorter than that in organic GHD($-4.13{\pm}1.28$ vs $-1.66{\pm}1.06$, P<0.001). Growth velocity during the first year of GH treatment was $9.69{\pm}3.19cm$(idiopathic GHD) and $7.87{\pm}3.65cm$(organic GHD). Height(SDS) at puberty in organic GHD was significantly greater than in idiopathic GHD ($-0.55{\pm}1.25$ vs $-2.28{\pm}0.95$, P<0.001). Final adult height(SDS) was significantly greater in organic GHD than in idiopathic GHD($0.22{\pm}1.06$ vs $-1.44{\pm}0.84$, P<0.001). In idiopathic GHD, total height gain (SDS) was most significantly correlated with midparental height minus initial height(MPH-IH)(SDS) (r=0.886, P<0.001). Total height gain(SDS) was more significantly correlated with MPH-IH(SDS) and prepubertal height gain(SDS) in idiopathic GHD(r=0.640, P=0.01, r=0.801, P<0.001). Conclusion : Final adult height was greater in organic GHD than in idiopathic GHD patients. While total height gain(SDS) was more pronounced in children with lower initial height compared to MPH, absolute final adult height was influenced by height at puberty. To improve the final adult height in children with GHD, height at onset of puberty must be increased by early diagnosis and continuous treatment with optimal doses of GH. There results should be evaluated with more patients.

• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.795-802
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• 2003

Purpose : We investigated the hormonal control of OB gene expression and leptin secretion in cultured human visceral adipose tissue. Methods : Visceral adipose tissues were cultured for up to 48 hrs in modified Eagle's medium with varying concentration of hormones : Control(no hormone), bovine insulin(100 nM), Dexamethasone(DEX, 100 nM), growth hormone(GH, 40 ng/mL), insulin+DEX(100 nM each), insulin+DEX+GH(100 nM insulin and DEX, 40 ng/mL GH). Quantitative analysis of leptin mRNA was performed by competitive reverse transcription polymerase chain reaction, and leptin secretion in culture medium was measured by IRMA using a commercial kit. Results : The addition of dexamethasone to the medium significantly increased OB gene expression and leptin secretion(P<0.05). Unlike dexamethasone, insulin did not affect OB gene expression and leptin secretion. Both insulin and dexamethasone, at high concentration, significantly stimulated leptin secretion compared with basal values(P<0.05). Leptin gene expression was not significantly increased by GH treatment alone, however GH, in combination with high concentrations of insulin and dexamethasone, attenuated the stimulatory effects of high concentrations of insulin and dexamethasone. Conclusion : Insulin cannot increase leptin secretion without the presence of dexamethasone. The mechanism suggested is that insulin may increase leptin secretion in cytoplasm only after dexamethasone increases the expression of OB gene. Further studies are necessary to elucidate the mechanism of the action of insulin on leptin secretion after increasing OB gene expression by dexamethasone.

• Clinical and Experimental Pediatrics
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• v.52 no.9
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• pp.1021-1028
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• 2009

Purpose:Medical therapy is the initial treatment for children with Graves disease to avoid complications of other treatments. However, optimal treatment for childhood Graves disease is controversial because most patients require relatively long periods of medical therapy and relapse is common after medication discontinuation. Therefore, this study aimed to search clinical or biochemical characteristics that could be used as remission predictors in Graves disease. Methods:We retrospectively studied children diagnosed with Graves disease, treated with anti-thyroid agents, and observed for at least 3 years. Patients were categorized into remission and non-remission groups, and the groups were compared to determine the variables that were predictive of achieving remission. Results:Sixty-four patients were enrolled, of which 37 (57.8%) achieved remission and 27 (42.2%) could not achieve remission until the last visit. Normalization of thyroid-stimulating hormone-binding inhibitory immunoglobulin (TBII) after treatment was faster in the remission group than in the non-remission group (remission group, $15.5{\pm}12.07$ vs. non-remission group, $41.69{\pm}35.70$ months). Thyrotropin-releasing hormone (TRH) stimulation tests were performed in 28 patients. Only 2 (8.3%) of 26 patients who showed normal or hyper-response in TRH stimulation test relapsed. Binary logistic regression analysis identified rapid achievement of TBII normalization after treatment as a significant predictor of remission. Six percent of patients achieved remission within 3 years and 55.8% achieved it within 6 years. Conclusion:Rapid achievement of TBII normalization can be a predictor of remission in childhood Graves disease. The TRH stimulation test can be a predictor of maintenance of remission.