• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.291-294
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• 2015

Persistent organic pollutants (POPs) including banned organochlorine pesticides, are found in Korean agricultural environments. Their translocation from agricultural environment to major crops has been reported. In this study, the POPs in 15 different agricultural waters of the Chungchung Province were monitored and all samples were prepared, followed by liquid-liquid fractionation and column chromatography prior to analysis using gas chromatography. Among pesticide-originated persistent organic pollutants, ${\alpha}$-endosulfan was determined in the range of 0.01 to 1.13 ng/mL. ${\beta}$-Endosulfan was determined in the range of 0.01 to 0.55 ng/mL, and endosulfan sulfate was ranged from 0.13 to 1.13 ng/mL. The total sum of endosulfans reached the range of 0.38 to 1.18 ng/mL. Three pesticides being used currently were also found in samples as 2.03-2.05 ng/mL for triadimefon, 0.26-0.33 ng/mL for tolyfluanid, and 1.34-3.85 ng/mL for chlorpyrifos. Taken together, endosulfans were introduced in the agricultural waters and their fates need continuous monitoring.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.2
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• pp.93-101
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• 2015

This study was conducted to analyze the relationship between tree-ring growth of Quercus acutissima and climatic variables by dendroclimatological method. Annual tree-ring growth data of Quercus acutissima collected by the $5^{th}$ National Forest Inventory (NFI5) were organized to analyze the spatial distribution of the species growth pattern. To explain the relationship between tree-ring growth of Quercus acutissima and climatic variables, monthly temperature and precipitation data from 1950 to 2010 were compared with tree-ring growth data for each county. When tree-ring growth data were analyzed through cluster analysis based on similarity of climatic conditions, four clusters were identified. In addition, index chronology of Quercus acutissima for each cluster was produced through cross-dating and standardization procedures. The adequacy of index chronologies was tested using basic statistics such as mean sensitivity, auto correlation, signal to noise ratio, and expressed population signal of annual tree-ring growth. Response function analysis was conducted to reveal the relationship between tree-ring growth and climatic variables for each cluster. The results of this study are expected to provide valuable information necessary for estimating local growth characteristics of Quercus acutissima and for predicting changes in tree growth patterns caused by climate change.

• Korean Journal of Environmental Agriculture
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• v.5 no.2
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• pp.85-94
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• 1986

To study fate of carbofuran in paddy system, C-14 labelled carbofuran was applied to paddy water containing rice seedlings and time course study was made on the distribution, metabolism and chemical transformation of the systemic insecticide. Carbofuran was readily absorbed by plant root and translocated to shoots where most of the radioactivities were confined to leaf tips. The fact that gradual increases in radioactivities of both aqueous phase extracts and non-extractable fractions of plants (shoots and root) increased with incubation is taken as an evidence that reactions (phase I and II) proceed in rice plants. Carbofuran and its five metabolites were all detected by TLC in organic phase extracts of paddy plants or soil. Evidence was put forward that carbofuran and its five metabolites were all identified as aglycones of conjugates. 7-benzofuranol and 3-hydroxycarbofuran were the most abundant aglycones. Soil microbes appears to have little effects on the metabolism of carbofuran. They increased radioactivity of non-extractable fraction and reduced that of organic phase extracts of paddy soil.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.51-65
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• 2015

The flora distributed around Mt. Hwangseok were summarized as 495 taxa including 97 families, 295 genera, 394 species, 4 subspecies, 80 varieties and 17 forms. In the component ratio of taxa, pteridophyta was 4.2%, 1.2% of gymnospermae, 78.8% of dicotyledonae and 15.8% of monocotyledonae. The rare plants were 9 taxa including Aconitum chiisanense, Eranthis stellata, Aristolochia contorta, Viola albida and so forth. The Korean endemic plants were 13 taxa including Populus tomentiglandulos, Pseudostellaria coreana, Aconitum pseudolaeve, Thalictrum actaefolium var. brevistylum and so forth. The specific plants by floristic region were 16 taxa including Cimicifuga heracleifolia, Sanguisorba longifolia, Symplocarpus renifolius, Betula davurica and so forth. The plants adaptable to climate change were 11 taxa including Aconitum pseudolaeve, Ajuga spectabilis, Carex okamotoi, Rhynchosia volubilis and so forth. The naturalized plants were 20 taxa including Fallopia convolvulus, Rumex crispus, Phytolacca amrericana, Robinia pseudoacacia and so forth. The invasive alien plant was Aster pilosus. The emergence of local ecologically important species, set the correct range for the core and buffer zone, transition zone, coded will be necessary, the distribution of the specialty plant areas and rare plants, an area management plan should be organized by nature. In addition, a variety of assessment techniques and accurate data to establish the validity of the core area is also set to acquire.

• Ecology and Resilient Infrastructure
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• v.2 no.4
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• pp.274-283
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• 2015

The reservoir shores seem to be vulnerable to biological invasion. The purpose of this research was to find out the floristic composition of alien plants and their relationship between environmental factors on reservoir shorelines in Korea. We investigated flora of alien plants and environmental factors of geomorphology, hydrology, water quality and soil on the shoreline of a total of 35 reservoirs with different water level managements. There were 56 species of alien plants, which was 15% of the total plant species identified in the study of reservoirs. A total of 57% of these alien species were the species which were introduced shortly after opening the port from 1876 to 1921 in Korea. More than 80% of the alien plants on the reservoir shores originated from America and Europe. The current distribution of Ambrosia trifida and Paspalum distichum were restricted in the central part and the southern region of the Korean Peninsula, respectively. The water level fluctuation, flood frequency at the median water level, water pollution index, coverage of rock exposure and mean degree of shoreline slope were determined as important environmental factors that have an effect on the characteristics of shoreline alien flora. Our results suggest that the reservoir shore was in danger of being invaded by alien plants due to the water level management and other human disturbances. For effective conservation of the reservoir ecosystem, periodic monitoring systems are required for the early detection of alien species on the reservoir shore.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.23 no.2
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• pp.49-67
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• 2020

This study was conducted to compare and analyze forest vegetation distributed in Geumosanseong-inside in Geumosan Provincial Park from 2017.10 to 2019.6. The vegetation structure was classified by the phytosociological method and TWINSPAN and the correlation between the community structure and the environmental factors was analyzed using DCCA ordination analydsis. The vegetation structures are Quercus mongolica, Fraxinus mandshurica, Q. acutissima, Larix leptolepis, Prunus padus and Morus alba community by the phytosociological method and 16 communities under TWINSPAN. The importance value of Q. mongolica(64.5) was the highest, and followed by F. mandshurica, L. leptolepis, Acer pseudosieboldianum, M. alba, P. padus, Q. acutissima, Sorbus alnifolia, P. serrulata var. pubescens, F. sieboldiana, Rhododendron schlippenbachii and Castanea crenata which is consistent with species having the dominance status by analysis of the vegetation structure. As the results of DBH analysis for taxon with high importance values, Q. mongolica and M. alba represented normal distribution, and thus, the dominance status of these species is likely to continue. L. leptolepis will maintain the dominance status due to high density of large individuals as compared with species above medium size. However, it will decrease because of high mortality after increase in age class. F. mandshurica and P. padus continue to show dominance status due to high density of young individuals as compared with species above medium size. Q. acutissima have high density of individuals above intermediate size and low density of young individuals, and thus, will maintain the dominance status. A. pseudosieboldianum, F. sieboldiana and R.schlippenbachii which are arborescent will present continuously high dominance status because of high density of young individuals. Soil analysis shows that whereas pH, Ca²⁺ and Mg²⁺ in the research area were lower than the average values of overall forest soil and O.M, T-N, C.E.C and P₂O₅ were higher. We expected that these results were due to agricultures until 50 years ago in Geumosanseong-inside. As a result of DCCA ordination analysis using eleven environmental factors and communities classified by the phytosociological method analysis showed that Q. mongolica was distributed in the environment with higher elevation and O.M and steep slope, and lower P₂O₅, Mg²⁺ and Ca²⁺. In contrast to F. mandshurica, Q. acutissima was distributed in higher K⁺ and lower pH. L. leptolepsis was distributed in various environment.

• Korean Journal of Clinical Laboratory Science
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• v.43 no.4
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• pp.171-178
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• 2011

Glycated hemoglobin ($HbA_{1c}$) is a most preferably used baseline of diabetes, implicating average blood glucose levels over a 2-3 month period of time. Recently the American Diabetes Association has recommended the $HbA_{1c}$ assay as one of the criteria for diabetes. Although some studies provide data with "estimated average glucose", by converting the $HbA_{1c}$ results from simple linear regression, the results are not applicable to whole diabetes. We compared the relationship between $HbA_{1c}$ and estimated average glucose by anemia degree of diabetic patients in Korea. The data from the 2008~2009 Korean National Health and Nutrition Examination Survey were used. Analysis was done for 1,257 diabetes subjects with $HbA_{1c}$ results. The distribution of subjects was 34.1% in 60's, 25.9% in 70's, 21,6% in 50's, showing that there was more than 80% in over 50's. To take a close look of the differences depending on the anemic degree, we applied WHO criteria (hemoglobin<13.0 in men and hemoglobin<12.0 in women) and divided anemia degree. The regression equation for A1c and estimated average glucose was $eAG_{mg/dL}=24.3{\times}A1c-32.0$ ($R^2=0.54$, p<0.001) in all subjects, $eAG_{mg/dL}=33.1{\times}A1c-96.1$ ($R^2=0.52$, p<0.001) in slight anemia ($11.0{\leq}$Hb<13.0 in men, $10.0{\leq}$Hb<12.0 in women), and $eAG_{mg/dL}=13.5{\times}A1c+34.9$ ($R^2=0.12$, p =0.075) in moderate anemia (Hb<11.0 in men, Hb<10.0 in women). The regression was not significant in moderate anemia. The relationship between HbA1c and eAG was lower correlation than ADAG study, and eAG showed lower value in all ranges among $HbA_{1c}$ 5~13%. Such as a korea where, there are many diabetic patients among the old aged and higher prevalence rate of anemia, we should be extra careful when we reflect eAG using $HbA_{1c}$ and need to establish criteria which can be applicable to koreans.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.3
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• pp.261-266
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• 2018

To determine the clinical utility of an immunoblot test and RT-PCR-hybridization test, 160 samples from patients with a chronic HCV infection were analyzed by two tests. A total of 133 samples out of 150 positive samples were positive by RT-PCR-hybridization. The true positive rate of the immunoblot tests and the concordance rate of the two tests was 88.6% and 89.3%, respectively. Serotyping and genotyping were performed to evaluate the distribution of the HCV subtype in Korean isolates. HCV serotypes 1 and 2, and genotypes 1b and 2a were the most common sources of HCV infections in this group. In 49 cases studied with the serotypes and genotypes, serotypes 1 and 2 were 57.1% and 42.9%, respectively. Genotypes 1b, 1b/2b, 2a, 2a/2c, and 2b were 51.0%, 2.0%, 34.7%, 8.2%, and 4.1%, respectively. This study shows that immunoblot tests are more useful for screening HCV infections. The RT-PCR-hybridization test confirmed the HCV infection in patients with positive immunoblot test results. The serotype test is preferred over the genotype test for monitoring the progression or response to treatment. On the other hand, there were no significant differences in the response to an ${\alpha}$-interferon treatment of HCV infection with serotype type 1 or type 2 in Korea.

• Journal of fish pathology
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• v.19 no.3
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• pp.267-276
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• 2006

Seventy-five streptococci were isolated from diseased olive flounder, Paralichthys olivaceus in Jeju. Their drug susceptibility and transferable multiple drug resistance were characterized. All isolates were resistant to flumequine (AR) and oxolinic acid (OA) and 26 isolates (34.7%) showed 4～6 multiple resistance of ampicillin (ABPC), AR, doxycycline (DOXY), erythromycin (EM), norfloxacin(NOR), OA and oxytetracycline (OTC) in various combinations. pST9 of a transferable R plasmid was detected from a multiple drug resistance strain, Streptococcus sp., ST9 originated from diseased flounder in Jeju, previously. We performed DNA hybridization to know the distribution of plasmid with the same DNA structure as pST9 in streptococci. Thirteen out of 60 isolates analyzed were positive in colony DNA hybridization and the part of bacteria isolated from raw meal was also hybridized with pST9. It suggested that raw meal is one of the origin of the resistance plasmid and R plasmid with DNA structure differing from pST9 is also involving in multiple drug resistance of the streptococci. In conjugation experiment, we found transferable R plasmid carrying OTC, DOXY and/or EM resistance determinant in the 13 resistance strains. all of the streptococci carrying the transferable R plasmid were similar in RAPD patterns. However, pST -type R plasmid was rare in S. iniae most frequently appearing in flounder farm.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.33 no.5
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• pp.353-361
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• 2015

The area of red tides occurences, which brings enormous damages every year, have been expanded to the coastal waters across the nation. Regarding to this trend, the development of red tide detection technology by using the GOCI (Geostationary Ocean Color Imager) of COMS lauched in 2010 has been drawn attentions of researchers. This study purposed on analyzing the frequency and density of red tides occurence by using the GOCI for detecting the southern sea, whereas targeted area. The observation has brought over the last three years (2012, 2013, and 2014) before the analysis was conducted. Followingly, the study could be resulted in extracting and revealing the hot spots of the red tides from two of analysis in the overlay and density. The distribution patterns of red tide occurrences according to those observed years has been shown in irregular characteristics and various changes. However, the analysis of hot spots, based on the frequency of the red tide occurrence, has revealed that the frequency of red tide occurences is continuously increased in the specific sea area. Therefore, it is concluded in that the continuous monitoring can contribute to predict accurate movements of red tides, so as establish systematic plans for preventing disasters.