• Korean Journal of Weed Science
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• v.10 no.2
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• pp.83-92
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• 1990

Experiment was conducted to establish the weed control system on the paddy fields by investigating species, period and amount of weeds in Gangwon province. Four locations were selected for these experiments : West plain area, Chunchon(74m above the sea level), mid-mountainous area, Hongchon(300 m), high alpine area, Hoengsong(450m), and east sea area, Myungju(14m). Weed emergence was investigated 6 times from 10 days after transplanting to 60 days with 10 days interval. From the experiments stated above, the results were summarized as follows ; The identity of weed species was small in grass family, but broad-leaf family was numerous. Also the dominant weed species was generally the perenial weeds. The weed emergence was initiated from 10 days after translanting. The amounts of weed counted the most in Chunchon. A large number of weeds were emerged between 30-60 days after transplanting in Chunchon and between 40-60 days after transplanting in Hongchon and Hoengsong. Among agronomic characteristics affected by weed emergence during rice development, plant height was decreased by 2~4cm, panicle number by 1.3~2.9, spikelet by 3.7~7.5, ripening rates 3.3~6.5%, and milled yield by 12~17%, respectively.

• Journal of Chest Surgery
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• v.39 no.11 s.268
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• pp.815-821
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• 2006

Background: Carotid endarterectomy is an effective treatment modality in patients with severe carotid artery stenosis, but it may result in serious postoperative complications, We analyzed the results of the carotid endarterectomy performed in our institution to reduce the complications related to the card endarterectomy. Material and Method: We analyzed retrospectively the medical records of 74 patients(76 cases) who underwent carotid endarterectomy for carotid artery stenosis by a single surgeon from February 1996 to July 2004. Result: There were 64 men and 10 women. The mean age of the patients was 63.6 years old. Carotid endarterectomy only was performed in 63 cases, carotid endarterectomy with patch angioplasty in 8 cases, and carotid endarterectomy with segmental resection of internal carotid artery and end to end anastomosis in 5 cases. Intra-arterial shunt was used in 29 cases. The mean back pressures of internal carotid arteries checked after clamping common carotid arteries and external carotid arteries were $23.48{\pm}10.04$ mmHg in 25 cases with changes in electroencephalography(group A) and $47.16{\pm}16.04$ mmHg in 51 cases without changes in electroencephalography(group B). There was no statistical difference in the mean back pressure of internal carotid arteries between two groups(p=0.095), but the back pressures of internal carotid arteries of all patients with changes in electroencephalography were under 40 mmHg. When there was no ischemic change of electroencephalography after clamping common carotid artery and external carotid artery, we did not make use of intra-arterial shunt regardless of the back pressure of internal carotid artery. Operative complications were transient hypoglossal nerve palsy in four cases, cerebral hemorrhage occurred at previous cerebral infarction site in two cases, mild cerebral infarction in one case, hematoma due to anastomosis site bleeding in one case, and upper airway obstruction due to laryngeal edema probably caused by excessive retraction during operation in two cases. One patient expired due to cerebral hemorrhage occurring at previous cerebral infarction site. Conclusion: Carotid endarterectomy is a safe operative procedure showing low operative mortality. We suggest that intra-arterial shunt usage should be decided according to the ischemic change of electroercephalography regardless of the back pressure of internal carotid artery. Excessive retraction during operation should be avoided to prevent upper alway obstruction due to laryngeal edema and if upper airway obstruction is suspected, prompt management is essential.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.94-102
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• 2008

The physico-chemical properties of ten reclaimed saline soils in five soil series of west-south Korea were analyzed according to the years past after reclamation. The soil samples were collected at the same sites two times in 2000 and 2004. The physico-chemical properties in 2000 had been changed in 2004 as follows. Soil salinity was the highest in Podu and desalinization period was the shortest in Munpo and Yeompo. Seasonal ground water level were above 100 cm in all regions that were 30 years old reclaimed tidal land, which was the same results of normal paddy field. In the case of soil physical changes, bulk density increased in fine textured soil (Poseung and Podu) but decreased in coarse textured soil (Gwanghwal, Munpo, and Yeompo). Porosity decreased in fine textured soil(Poseung and Podu) but increased in coarse textured soil. These reason were as follows. Fine textured soil were increased in solid phase but decreased in liquid and gaseous phase. Coarse textured soil, Gwanghwal and Munpo except for Yempo, were increased in gaseous phase but decreased in solid and liquid phase. Yempo that have low water table level were increased in liquid phase but decreased in solid and gaseous phase. Soil hardness increased in 4 soil series except for Munpo. In the case of chemical property changes, although there were more or less difference, it showed decreasing tendencies. Soil pH, the content of organic matter, available phosphate, and available silicate of five soil series were decreased during the four years. The content of exchangeable cation also decreased except for magnesium.

• Journal of Environmental Impact Assessment
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• v.30 no.1
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• pp.35-48
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• 2021

In this study, the assessment of field applicability of in-situ remediation of nitrate-contaminated groundwater located in Yesan-gun was performed. Zero-valent iron/bio composite media injected PRB (Permeable Reactive Barrier) and monitoring well were installed in the contaminated groundwater site and monitored main remediation indicators during the PRB operation. Nitrate, nitrite, ammonia, Fe ion, TOC, and turbidity were analyzed and the diversity and population of microorganism in the PRB installed site were investigated for the verification of effect of injected PRB. In the study site where is an agricultural area, a river flows from west to east that forms a river boundary and the southern area has an impermeable sector. It was found that nitrate flows into the river, which is similar as groundwater flow. Simulation result for the fate of nitrate in groundwater showed steady state of nitrate arrived after 3~5 years passed. However, it is just to consider current conditions with no additional input of contaminant source, if additional input of contaminant source occurs contamination dispersion and time for steady state are expected to be increased. The monitoring results showed that Fe ion, TOC and turbidity in groundwater were not clearly changed in concentration after PRB installation, which indicates adaptability of the injected PRB for remediation of groundwater with no additional harmful effect to water quality. The concentration of nitrate maintained less than 5mg/L until 42 days after PRB installation and recovered its initial concentration after 84 days passed and showed termination of reactivity of injected zero-valent iron/bio composite media for removal nitrate. Nitrite and ammonia ions found after installation of PRB indicates reductive removal of nitrate. And the outstanding increase of microorganism diversity and population of Betaproteobacteria Class which includes denitrification microorganism explains biologically reductive removal of nitrate in injected PRB.

• Journal of Korea Water Resources Association
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• v.55 no.6
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• pp.393-404
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• 2022

Reliable terrestrial rainfall observations from satellites at finer spatial resolution are essential for urban hydrological and microscale agricultural demands. Although various traditional "top-down" approach-based satellite rainfall products were widely used, they are limited in spatial resolution. This study aims to assess the potential of a novel "bottom-up" approach for rainfall estimation, the parameterized SM2RAIN model, applied to the C-band SAR Sentinel-1 satellite data (SM2RAIN-S1), to generate high-spatial-resolution terrestrial rainfall estimates (0.01° grid/6-day) over Central South Korea. Its performance was evaluated for both spatial and temporal variability using the respective rainfall data from a conventional reanalysis product and rain gauge network for a 1-year period over two different sub-regions in Central South Korea-the mixed forest-dominated, middle sub-region and cropland-dominated, west coast sub-region. Evaluation results indicated that the SM2RAIN-S1 product can capture general rainfall patterns in Central South Korea, and hold potential for high-spatial-resolution rainfall measurement over the local scale with different land covers, while less biased rainfall estimates against rain gauge observations were provided. Moreover, the SM2RAIN-S1 rainfall product was better in mixed forests considering the Pearson's correlation coefficient (R = 0.69), implying the suitability of 6-day SM2RAIN-S1 data in capturing the temporal dynamics of soil moisture and rainfall in mixed forests. However, in terms of RMSE and Bias, better performance was obtained with the SM2RAIN-S1 rainfall product over croplands rather than mixed forests, indicating that larger errors induced by high evapotranspiration losses (especially in mixed forests) need to be included in further improvement of the SM2RAIN.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.4
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• pp.266-274
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• 1999

Vertical CTDT measurement at one point near tidewater glacier of fjord-head in Marian Cove, a tributary embayment of Maxwell Bay, South Shetland Islands was performed for 24 hours during the austral summer (January 21-22, 1998) to present water-column properties and SPM (suspended particulate matter) dispersal pattern in subpolar glaciomarine setting. Marian Cove shows three distinct water layers: 1) cold, freshened, and highly turbid surface plume in the upper 2 m, 2) warm, saline, and relatively clean Maxwell Bay water between 15-35 m in water depth, and 3) cold and turbid mid plume between 40-65 m in water depth. The surface plume is composed of silt-sized clastie particles mixed with flocculated biogenic detritus, and appears to originate from either supraglacial discharge by meltwater streams along the coast or water fall of ice cliff. Freshened and turbid mid plume consists exclusively of silt-sized clastic particles, resulting from subglacial discharge beneath the tidewater glacier. The disappearance of the two turbid plumes during the earlier period of measurement seems to be largely due to the breakup of the plumes by upwelling caused by strong easterly wind (> 8 m $sec^{-1}$). Thus, wind coupling over tidal effects regionally plays a major role in dispersal pattern of SPM as well as water exchange in Marian Cove.

• Clinical and Experimental Pediatrics
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• v.48 no.7
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• pp.779-788
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• 2005

Purpose : Echinacea, a traditional plant medicine has been used as immune-stimulant. Recent studies have revealed that extract of Echinacea has immunostimulatory effects on human blood mononuclear cells. This study was designed for the purpose of screening the genes associated with immunologic effects of Echinacea on monocytes and dendritic cells using a cDNA microarray chip. Methods : $CD14^+$ monocyte cells were cultured for one day with Echinacea extract(final concentration : $50{\mu}g/mL$) in experiment 1, but were cultured without Echinacea in experiment 2. The gene expression of these cultured monocytes was analyzed using the cDNA microarray chip. Dendritic cells produced from $CD14^+$ monocyte were cultured for five days with GM-CSF and IL-4, and then cultured for one day with Echinacea in experiment 3, but were done without Echinacea in experiment 4. Results : In experiments 1 and 2, there were 17 significantly expressed genes with average expression ratios above 2.5, including interferon gamma-inducible protein 30(IFI 30), CDC(cell-division-cylcle)-like kinase 2(CLK 2), syndecan binding protein(syntenin), superoxide dismutase 2, etc. In experiments 3 and 4, there were 24 gene, with significantly expressed genes were 24 genes, which were insulin-like growth factor 2(somatomedin A), methyl-CpG binding domain protein 3, IFI 30, small inducible cytokine subfamily A, member 22, etc. The genes encoding CD44, IFI 30, mannose receptor C type 1(MRC 1), chemokine receptor 7(CCR 7), CLK 2, syntenin and cytochrome C oxidase subunit VIII were significantly expressed in both monocytes and dendritic cells cultured with Echinacea. Conclusion : This study employed a cDNA microarray chip to elicit the immune-associated gene profile; the expression was enhanced by Echinacea in CD14+ monocytes and dendritic cells. Thus we laid the basis for the quantitative and functional analysis of genes induced by Echinacea in monocytes and monocyte-derived dendritic cells.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.3
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• pp.154-162
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• 2011

Seawater quality was investigated each month at 30 stations near Tongyeong, South Korea, to provide data for the effective use of coastal fisheries and the reduction of economic damage to marine products. Water temperature was lowest in January and highest at the end of August. Neither extremely low water temperature below $4^{\circ}C$ nor fish damage caused by low water temperature was observed. Salinity ranged from 24.04 to 34.39 psu in the surface layer and from 29.92 to 34.39 psu in the bottom layer. The minimum salinity, attributable to rainfall events, was observed in July; salinity increased to high of about 34 psu in November. Low dissolved oxygen (DO), below 4 mg/L, was observed at Wenmun and Buksin Bays during May to October. Concentrations of $NO_2$-N, $NO_3$-N, and $PO_4$-P were low from March to September and high from October to February. Transparency was 6 m on average and was high in Wenmun Bay. Chemical oxygen demand (COD) and chlorophyll a (Chl. a) were high during summer, when the water temperature was high. With cluster analysis based on environment factors related to water quality, the study area could be divided into three main sea areas: Buksin Bay, coastal seawater, and offshore seawater. Buksin Bay was characterized by low salinity, high DO and Chl. a, and high transparency in the surface layer and by low DO and high $NH_4$-N in the bottom layer. Offshore seawater had high salinity and $NO_3$-N and low Chl. a concentration. In summer season that oyster need lots of phytoplankton, $NO_3$-N and Chl. a concentrations at this study area were low compare to Gwangy-ang and Gamak Bays. In winter, a sea squirt swallow much more than other season, the Chl. a concentrations were also low than Gwangyang and Gamak Bays.

• Clinical and Experimental Pediatrics
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• v.45 no.12
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• pp.1559-1570
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• 2002

Purpose : There has been no exact answer to the question of when to discontinue antiepileptic drugs(AEDs) in children with well-controlled epilepsy for a long period. This study is about the risk factors of relapse after withdrawal of AEDs in seizure(Sz)-free patients to show a guideline for discontinuation of AEDs. Methods : One hundred and sixty-nine children were diagnosed as epileptic at the Pediatric Dept. of Kyung-Hee Univ. between 1993 to 1998, in whom AEDs had been withdrawn after at least two years of Sz-free period. Univariate analysis using Kaplan-Meier survival analysis and multivariate analysis using Cox-proportional hazard model were performed for sixteen risk factors. Results : Forty-nine of the 169 patients(28.9%) had recurrence of Szs. The mean follow-up after withdrawal of AEDs was 4.1 years, mean treatment period was 4.1 years, and the mean Sz-free period was 3.3 years. Factors associated with an increased risk of relapse were young age at onset, symptomatic Sz, Sz type in West and Lennox-Gastaut syndrome, neurologic deficit, longer Sz-controlling period, shorter total treatment period, number of AEDs used(more than one drug), age at withdrawal of AEDs, and Sz-free period less than two years in univariate analysis using Kaplan-Meier mothod. From multivariate analysis, the factors indicating a significantly higher relapse risk were pre-treatment period after first Sz attack, Sz-controlling period, Sz-free period, number of AEDs used, neurologic abnormalities. Conclusion : For epileptic children who were Sz-free for more than two years, and were more than six-years-old, the discontinuation of AEDs should be considered positively, according to age of onset, Sz type, age at withdrawal of AEDs, total treatment period, Sz-controlling period, number of AEDs used, etiology, neurologic deficit, and the wishes of the patients and the their parents.

• Journal of Animal Science and Technology
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• v.52 no.5
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• pp.383-388
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• 2010

Identification of natural compounds that can prevent the development of obesity in vivo is time consuming and expensive. We have used in vitro systems derived from pig adipose tissue to screen simple aqueous or ethanolic extracts of Korean medicinal herbs (KMH) for their anti-adipogenic potential. A total of 183 extracts were tested for their actions in lipogenesis of pig adipose tissue and differentiation of pig preadipocytes. Ethanol extracts were prepared from 72 and aqueous extracts were prepared from 111 medicinal herbs. Both an ethanolic and an aqueous extract were prepared from 65 of these. Thirteen extracts substantially altered rates of lipogenesis in vitro. The effects of KMH on lipogenesis of pig adipose tissue are as follows. Elevens reduced lipogenesis to rates that were more than 40% lower than control and four of these reduced rates of lipogenesis by more than 70%. The most potent anti-lipogenic extracts were those obtained in ethanol from Iridaceae and from Sophora flavescens AIT as well as both the aqueous and ethanolic extracts from Lysimachia vulgaris L. Two extracts, those prepared in water from Caesalpiniae lignum and from Phellodendri cortex, were found to promote rates of lipogenesis in vitro. The effects of KMH on differentiation of pig preadoipocytes are as follows. Twentyeight extracts altered the rates of differentiation of cultured porcine preadipocytes. Sixteen increased and twelve reduced the rates of differentiation of preadipocytes. Extracts prepared in ethanol from Moutan radicis cortex and from Ostericum koreanum and those prepared in water from Angelicae gigantis radix, from Inula henenium L and from Magnolia flos doubled the rate of differentiation of cultured porcine preadipocytes. Ten extracts reduced the in vitro rate of differentiation of porcine preadipocytes by more than 35%. These were the ethanolic extracts from Glycyrrizae radix, Nepetae spica and from Polygala myrtifolia and the aqueous extracts from Amaranthaceae, Asparagus cochinchinesis, Atractylodis rhizoma alba, Citrus junos TANAKA, Cyperus rotundus, Epimedium grandiflorum and from Moutan radicis cortex. Only the ethanolic extract from Polygala myrtifolia was able to both reduce lipogenesis in adipose tissue slices and retard differentiation of cultured preadipocytes. The results of our study will provide meaningful information to identify medicinal herbs which would reduce fat deposition in livestocks and humans.