• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1193-1200
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• 2005

Purpose : Invasive bacterial infection is a major cause of morbidity and mortality in children. Previously, we reported etiology of invasive infections in healthy children in 1985-1995. This study was performed to update etiology of invasive bacterial infections in the previously healthy children. Methods : We reviewed medical records of 98 episodes of invasive bacterial infections in immunocompetent children at the Seoul National University Children's Hospital in 1996-2004. Results : The frequent pathogens identified over all age groups were Streptococcus pneumoniae (33%) and Staphylococcus aureus(33%). The proportion of Salmonella species and Haemophilus influenzae has been declined to 4% each from 23% and 14%, respectively, compared to previous study. S. agalactiae was the most common isolate in the infants ${\leq}3$ months. Among the infants and children aged 3 months to 2 years and children of 2-5 years, S. pneumoniae(57%, 52%, respectively, in each group) was the most common isolates followed by S. aureus(17% and 24%, respectively). S. aureus was the most common isolates(73%) in children >5 years. Primary bacteremia was the most common clinical diagnosis(27%). S. pneumoniae was responsible for 42% of primary bacteremia, 50% of meningitis, and 69% of bacteremic pneumonia and empyema. S. aureus accounted for 80% of bone and joint infections. The case fatality rate was 8.1% for all invasive infections. Conclusion : We reviewed frequency of bacterial agents of invasive infections in children. The data may be useful for pediatricians to select adequate empirical antibiotics in the management of invasive bacterial infections.

• Economic and Environmental Geology
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• v.50 no.2
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• pp.171-180
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• 2017

This study performed the analysis on the volcanic gases and hot spring waters from the Julong hot spring at Mt. Baekdu during the period from July 2015 to August 2016. Also, we confirmed the errors that $HCO_3{^-}$ concentrations of hot spring waters in the previous study (Lee et al. 2014) and tried to improve the problem. Dissolved $CO_2$ in hot spring waters was analyzed using gas chromatograph in Lee et al. (2014). Improving this, from 2015, we used TOC-IC to analysis dissolved $CO_2$. Also, we analyzed the $Na_2CO_3$ standard solutions of different concentrations using GC, and confirmed the correlation between the analytical concentrations and the real concentrations. However, because the analytical results of Julong hot spring water were in discord with the estimated values based on this correlation, we can't estimate the $HCO_3{^-}$ concentrations of 2014 samples. During the period of study, $CO_2/CH_4$ in volcanic gases are gradually decreased, and this can be interpreted in two different ways. The first interpretation is that the conditions inside the volcanic edifice are changing into more reduction conditions, and carbon in volcanic gases become more favorable to distribute into $CH_4$ or CO than $CO_2$. The second interpretation is that the interaction between volcanic gases and water becomes greater than past, and the concentrations of $CO_2$ which have much higher solubility in water decreased, relatively. In general, the effect of scrubbing of volcanic gas is strengthened during the quiet periods of volcanic activity rather than active periods. Meanwhile, the analysis of hot spring waters was done on the anion of acidic gases species, the major cation, and some trace elements (As, Cd, Re).

• Korean Journal of Environmental Agriculture
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• v.11 no.1
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• pp.9-19
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• 1992

To ditermine the accumulation of Cu and Pb in crops grown on Sludge-treated Soils, four crop plants, green onion(A Ilium ascalonicum L.), radish(Raphanus sativus L.), potato(Solanum tuberosum L.) and Chinese cabbage(Brassica pekinensis Rupr), were grown in greenhouses on soils treated with municipal sewage sludge at different levels of 0, 22.5, 45, and 90ton/ha as soil dry weight. The contant of heavy metals were analyzed in plant parts of the crop species and the statistical characteristics were investigated. The results were as follows: 1. Cu and Pb contents in experimental plants were increased in accordance with quanti of sludge applied. 2. Accumulation of Cu and Pb in leaves of plants was increased in order of radish

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.243-258
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• 1977

1 The coastal area between Youngdo and Jodo was a common coastal water not much different from other coastal waters before the construction of the breakwater between them. 2. The breakwater between the two islands shuts off the tidal currents and divides the area . into the two small isolated bays to create quite different environments. 3. To understand the differences between then, present study examined some environmental factors such as water temperature, salinity, dissolved oxygen, transparency, and major nutrients, phosphates, sillicates and nitrites and the phytoand zooplankton. The samplings were carried out monthly from March 1976 to February 1977 at 4 stations: 2 stations in each bay. 4. Some differences were observed in the environmental factors such as water temperature, salinity, dissolved oxygen and transparency between the two bays. 5. The distribution and occurence of nutrient salts of the two bays were distinctly different each other. Northern Bay had $138\%$ of nutrients in comparison with Southern Bay. 6. Phytoplankton in Northern Bay was about $200\%$ plentier than in Southern Bay. 7. Zooplankton in Southern Bay was about $180\%$ richer than in Northern Bay. 8. One of the pollution indicator species, Synedra ulna, was observed in Northern Bay and the occurence of Euglena sp. and ciliates were much higher in Northern Bay than in Southern Bay, but, in contrast, Sagitta sp. was more abundant in Southern Bay than in the other. 9. The areas of the two bays seem to be in its way to eutrophication especially in Northern Bay. 10. The two bays have been differentiated enough to identify each other.

• The Korean Journal of Pesticide Science
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• v.13 no.4
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• pp.298-308
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• 2009

A flexuous rod-shaped virus was isolated from Cucurbita pepo leaves showing as green mosaic and puckering symptoms at Anseong, Korea. Based on the biological analysis, electron microscopy, and reverse transcription-polymerase chain reaction (RT-PCR), the virus isolate was identified as Papaya ringspot virus type watermelon (PRSV-W). From biological analysis, the host range of PRSV-W was limited to the families Cucurbitaceae and Chenopodiaceae. Most susceptible cucurbit species, such as Cucumis lanatus, Cucumis sativus, Cucurbita pepo, and Citrullus lanatus, showed symptoms of green mosaic, malformation, puckering, and narrow laminae by infection with PRSV-W. The local lesion were showed on the inoculated leaves of both Chenopodium amaranticolor and C. quinoa. Field survey of PRSV, Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV), three major viruses infecting cucurbit, was done during 2001 to 2003 on 173 commercial cucurbit cultivating fields distributed over the three regions of Gyeonggi, Gyeongbuk and Jeonnam Provinces where cucurbits are grown in different environmental conditions and cropping patterns. Typical viral symptoms were observed from 107 cultivating fields, and all three kinds of potyviruses were detected from 206 samples out of the 235 samples using RT-PCR. Watermelon mosaic virus (WMV) and Zucchini yellow mosaic virus (ZYMV) are the most widely distributed viruses in outdoor and retarding-culture fields, at an infection rating of 48 and 33 percents, respectively. PRSV was detected from 12 percent of 235 samples. The nucleotide and amino acid sequences of coat proteins (CP) of eight PRSV isolates, collected from several areas including Anseong, were determined and sequenced heterogeneity among the isolates was performed. The CP gene of PRSV showed 88.6~97.3 percent homology in nucleotide sequences and 95.1~99.3 percent homology in amino acid sequences with other PRSV isolates worldwide. The phylogenetic analysis indicated that the Korean PRSV isolates belong to the southern-east Asian cluster.

• Journal of the Korean Applied Science and Technology
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• v.5 no.1
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• pp.13-23
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• 1988

Contents of total lipids, neutral lipids, glycolipids and phospholipids of seed oils of 16 species of the Labiatae family were determined and their fatty acid compositions were analyzed by gas-liquid chromatography. The results were summarized as follows. 1) Lipid contents of seeds were shown to be 40.6％ in Perilla frutescens Britton var. japonica, 32.2％ in P. frutescens britton var. acuta, 31.9％ in lsodon japonicus, 32.7% in l. inflexus, 48.3％ in l. serra, 35.1％ in Mosls dianthera, 38.2％ in M. punctulata, 33.4％ in Nepeta cataria, 26.3％ in Agastache rugosa, 30.9％ in Eisholtzia ciliata, 18.9％ in Salvia splendens, 23.9％ in Lycopus maackianus, 49.5％ in Clinopodium chinense var. parviflorum, 30.9％ in Ametystea caerulea, 33.1％ in Leonurus sibircus and 34.3％ in Scutellaria basicalensis. 2) Contents of neutral lipids, glycolipids and phospholipids from the seed oils amounted to 98.6％, 0.7％, 0.8％ in P. frutescens Britton var. japonica; 95.5％, 1.3％, 3.1％ in P. frutescens Britton var. acuta; 95.1％, 1.8％, 3.1％ in l. japoincus; 91.4％, 3.5％, 5.1％ in l. inflexus; 96.8％, 0.7％, 2.5％ in l, serra; 96.0％, 1.8％, 2.2％ in Mosla dianthera; 94.7％, 2.0％, 3.3％ in M. punctulata; 90.1％, 2.4％, 7.5％ in Nepeta cataria; 90.1％, 3.4％, 6.5％ in Agastache rugosa; 86.3％, 3.3％, 10.4％ in Elsholtzia ciliata; 94.3％, 1.5％, 4.3％ in Salvia splendens; 87.2％, 2.9％, 9.0％ in Lycopus maackianus; 87.0％, 1.5％, 11.5％ in Clinopodium chinense var. parviflorum; 91.8％, 1.6％, 6.6％; 95.5％, 0.4％, 4.1％ in Leonurus sibricus; 89.0％, 1.4％, 9.6％ in Scutellaria baicalensis. 3) Total lipids revealed the predominace of unsaturated fatty acids (82.0-94.5％) and larger variations were found in the composition of ${\alpha}-linolenic$ acid (0.4-67.9％) and linoleic acid (11.2-82.9％). High level of ${\alpha}-linoenic$ acid was present in P. frutescens Britton var. japonica (67.9％), P. frutescens Britton var, acuta (66.0％), lsodon japonicus (65.2％), l. inflexus (59.0％), l. serra (57.3％), Mosla dianthera (60.9％), Nepeta cataria (58.3％), Agastache rugosa (58.5％) and Elsholtzia ciliata (46.2％), and followed by linoleic acid (11.2-32.1％) and oleic acid (9.3-12.2％). However, linoleic acid was the most predominant component in the total lipids of Clinopodium chinense var. parviflorum (62.4％), Ametystea caerules (82.9％), Leonurus sibricus (60.9％) and Scutellaria baicalensis (63.4％), with very small amounts of ${\alpha}-linolenic$ acid (0.4-3.1％). The total lipids of Salvia splendens, Lycopus maackianus and Mosla punctulata also contained linoleic acid of 31.3％, 48.8％ and 53.4％, with a considerable amount of ${\alpha}-linolenic$ acid of 34.5％ 27.0％ and 16.7％. Palmitic acid was the major saturated fatty acid in all the oils investigated (4.1-14.2％). 4) Fatty acid profiles of neutral lipids bore a close resemblance to those of total lipids in all the seed oils, but different from those of glycolipids and phospholipids. Fatty acid composition pattern of glycolipids and phospholipids showed a considerably increased level of saturated fatty acids (19.0-66.8％, 17.8-35.2％) mainly composed of palmitic acid and stearic acid, and a noticeable low level of unsaturated fatty acids (41.2-80.9％, 64.7-82.1％) which was ascribed to the decrease in ${\alpha}-linolenic$ acid of high ${\alpha}-linolenic$ acid seed oils, and in linoleic acid of high linoleic seed oils, compared to that of total lipids and neutral lipids.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.5
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• pp.446-452
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• 1986

This paper presents the composition of neutral and polar lipids obtained from puple shell, Rapana venosa and the abalone, Haliotis discus hannai. The fatty acid composition and the classification of neutral lipids from two species were determined by gas chromatography (GLC) and thin layer chromatography (TLC). Total lipid contents of samples were $0.5\%$ in purple shell and $0.4\%$ in the abalone. The predominant fatty acids of total lipids were eicosapentaenoic acid ($19.30\%$). eicosenoic acid ($12.10\%$) and palmitic acid ($11.77\%$) in the purple shell, and palmitic acid ($21.29\%$), oleic acid ($14.55\%$) and linoleic acid ($14.21\%$) in the abalone. The lipid composition of non-polar lipid fractions in purple shell and abalone was separated and identified as free sterol, free fatty acid, triglyceride and hydrocarbon & esterified sterol by TLC. The contents of triglyceride from both neutral lipids were shown more abundant than any other subclasses. The main fatty acids of neutral lipids were eicosapentaenoic acid ($18.6\%$), palmitic acid ($14.90\%$) and eicosenoic acid ($14.76\%$) in the purple shell, and palmitic acid ($28.12\%$), oleic acid($20.5\%$) and myristic acid ($12.5\%$) in the abalone. Eicosapentaenoic acid ($17.57\%$), stearic acid ($13.26\%$) and eicosatetraenoic acid ($11.24\%$) were important fatty acids of glycolipid in the purple shell, and myristic acid ($12.75\%$), stearic acid ($12.10\%$) and eicosatetraenoic acid ($10.64\%$) in the abalone. The major fatty acids of phospholipids were eicosapentaenoic acid ($20.18\%$), palmitic acid ($11.26\%$) and eicosenoic acid ($10.90\%$) in the purple shell, and palmitic acid ($21.10\%$), eicosapentaenoic acid ($12.90\%$) and oleic acid($11.13\%$) in the abalone.

• The Korean Journal of Pharmacology
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• v.30 no.3
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• pp.321-330
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• 1994

The protective effect of 'ischemic preconditioning (PC)' on ischemia-reperfusion injury of heart has been reported in various animal species, but without known mechanisms in detail. In an attempt to investigate the cardioprotective mechanism of PC, we examined the effects of PC on the myocardial oxidative injuries and the oxygen free radical production in the ischemia-reperfusion model of isolated Langendorff preparations of rat hearts. PC was performed with three episodes of 5 min ischemia and 5 min reperfusion before the induction of prolonged ischemia (30 min)-reperfusion(20 min). PC prevented the depression of cardiac function (left ventricular pressure x heart rate) observed in the ischemic-reperfused heart, and reduced the release of lactate dehydrogenase during the reperfusion period. On electron microscopic pictures, myocardial ultrastructures were relatively well preserved in PC hearts as compared with non-PC ischemic-reperfused hearts. In PC hearts, lipid peroxidation of myocardial tissue as estimated from malondialdehyde production was markedly reduced. PC did not affect the activity of xanthine oxidase which is a major source of oxygen radicals in the ischemic rat hearts, but the myocardial content of hypoxanthine (a substrate for xanthine oxidase) was much lower in PC hearts. It is suggested from these results that PC brings about significant myocardial protection in ischemic-reperfused heart and this effect may be related to the suppression of oxygen free radical reactions.

• The Journal of the Petrological Society of Korea
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• v.13 no.1
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• pp.34-45
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• 2004

This paper describes the textural relations of mantle xenoliths and fluid inclusions in mantle-derived rocks found in alkaline basalts from Jeju Island which contain abundant ultramafic, felsic, and cumulate xenoliths. Most of the ultramafic xenoliths are spinel-lherzolites, composed of olivine, orthopyroxene, clinopyroxene and spinel. The felsic xenoliths considered as partially molten buchites consist of quartz and plagioclase with black veinlets, which are the product of ultrahigh-temperature metamorphism of lower crustal materials. The cumulate xenoliths, clinopyroxene-rich or clinopyroxene megacrysts, are also present. Textural examination of these xenoliths reveals that the xenoliths are typically coarse grained with metamorphic characteristics, testifying to a complex history of evolution of the lower crust/upper mantle source region. The ultramafic xenoliths contain protogranular, porphyroclastic and equigranular textures with annealing features, indicating the presence of shear regime in upper mantle of the Island. The preferential associations of spinel and olivine with large orthopyroxenes suggest a previous high temperature equilibrium in the high-Al field and the original rock-type was a Al-rich orthopyroxene-bearing peridotite without garnet. Three types of fluid inclusions trapped in mantle-derived xenoliths include CO$_2$-rich fluid (Type I), multiphase silicate melt (glass ${\pm}$ devitrified crystals ${\pm}$ one or more daughter crystals ＋ one or more vapor bubbles) (Type II), and sulfide (melt) inclusions (Type III). C$_2$-rich inclusions are the most abundant volatile species in mantle xenoliths, supporting the presence of a separate CO$_2$-rich phase. These CO$_2$-rich inclusions are spatially associated with silicate and sulfide melts, suggesting immiscibility between them. Most multiphase silicate melt inclusions contain considerable amount of silicic glass. reflecting the formation of silicic melts in the lower crust/upper mantle. Combining fluid and melt inclusion data with conventional petrological and geochemical information will help to constrain the fluid regime, fluid-melt-mineral interaction processes in the mantle of the Korean Peninsula and pressure-temperature history of the host xenoliths in future studies.

• Journal of the Mineralogical Society of Korea
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• v.29 no.2
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• pp.59-71
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• 2016

To investigate the sorption characteristics of Cs, which is one of the major isotopes of nuclear waste, on natural zeolite chabazite, XRD, EPMA, EC, pH, and ICP analysis were performed to obtain the informations on chemical composition, cation exchange capacity, sorption kinetics and isotherm of chabazite as well as competitive adsorption with other cations ($Li^+$, $Na^+$, $K^+$, $Rb^+$, $Sr^{2+}$). The chabazite used in this experiment has chemical composition of $Ca_{1.15}Na_{0.99}K_{1.20}Mg_{0.01}Ba_{0.16}Al_{4.79}Si_{7.21}O_{24}$ and its Si/Al ratio and cation exchange capacity (CEC) were 1.50 and 238.1 meq/100 g, respectively. Using the adsorption data at different times and concentrations, pseudo-second order and Freundlich isotherm equation were the most adequate ones for kinetic and isotherm models, indicating that there are multi sorption layers with more than two layers, and the sorption capacity was estimated by the derived constant from those equations. We also observed that equivalent molar fractions of Cs exchanged in chabazite were different depending on the ionic species from competitive ion exchange experiment. The selectivity sequence of Cs in chabazite with other cations in solution was in the order of $Na^+$, $Li^+$, $Sr^{2+}$, $K^+$ and $Rb^+$ which seems to be related to the hydrated diameters of those caions. When the exchange equilibrium relationship of Cs with other cations were plotted by Kielland plot, $Sr^{2+}$ showed the highest selectivity followed by $Na^+$, $Li^+$, $K^+$, $Rb^+$ and Cs showed positive values with all cations. Equilibrium constants from Kielland plot, which can explain thermodynamics and reaction kinetics for ionic exchange condition, suggest that chabazite has a higher preference for Cs in pores when it exists with $Sr^{2+}$ in solution, which is supposed to be due to the different hydration diameters of cations. Our rsults show that the high selectivity of Cs on chabazite can be used for the selective exchange of Cs in the water contaminated by radioactive nuclei.