• Parasites, Hosts and Diseases
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• v.31 no.3
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• pp.249-258
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• 1993

Naegleria fowleri is the cause of primary amoebic meningoencephalitis in man, IL-2 levels after stimulation of T lymphocytes by PHA or N.fowleri lysates. the amounts of T lymphocyte subsets and the blastogenic responses of T lymphocytes in mice after Infected with pathogenic N. fowleri were studied comparing between two study groups, one $1{\;}{\times}{\;}10^4$ trophozoites inoculated mice and the other $1{\;}{\times}{\;}10^5$ trophozoites inoculated mice. All experimental samples were obtained on the day 7, 14 and 24 after inoculation. The mice inoculated with $1{\;}{\times}{\;}10^4$ trophozoites showed a 14.3% mortality rate, and 72.2% in the mice inoculated with $1{\;}{\times}{\;}10^5$ trophozoites. The IL-2 levels on day 14 of two experimental groups were significantly decreased as compared with the control group. Thy 1.2+T cells in the total spleen Iymphocytes of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group on day 7 were significantly increased compared with the control group. There was no significant difference between $1{\;}{\times}{\;}10^4$ trophozoites inoculated group and the control group. $L3T4^{+}{\;}T$ cells and $Ly2^{+}$ T cells in the total spleen Iymphocytes of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group on day 7 were sigrlificantly increased compared with the control group. The DNA S fraction of T cells in the spleen of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group was significantly increased on day 7. The amount of S fractions of DNA were sequentially decreased on day 14 and 24 but they were also signiacantly increased compared with the control group. The results obtained in the experiments indicats that cell mediated immunity after N.fowleri infection acts on very important host's protection immunity around the 7th day after infection. IL-2 level was much suppressed on day 14 which resulted from the exhaustion of host immune response. It was observed that the level of IL-2 production ability and the amounts of T lymphocytes subsets and the blastogenic responses of T lymphocytes were not well correlated during the observation period.

• Journal of the Korean Society for Marine Environment & Energy
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• v.11 no.4
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• pp.199-213
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• 2008

Saemangeum salt-water Lake has been created by the completion of the sea-dike in April 2006. To monitor the water qualities of the lake during the sea-dike construction, salinity, SS, nutrients(DIN, DIP, DISi), and chlorophyll-$\alpha$ was analyzed for the surface water from 1999 to 2007. Due to the dike construction, weaker tidal current and lesser resuspension of bottom sediment resulted in the marked decrease of the concentrations of SS in the lake water. Consequently the clearer lake water has provided better condition for primary production with deeper penetration of sunlight into the water column and sufficient nutrient content in the water. Finally the chlorophyll-$\alpha$ content became approximately double in the concentration after the dike construction. Highly stimulated algal production with the marked decrease of the concentrations of SS was decreased the concentration of DIP in the surface water. On the other hand the concentration of DIN and DISi in surface water was increased after dike construction due to the expansion of the freshwater and the supply from bottom layer. As a result, the lake revealed an extremely high NIP ratio and a DIP-limited ecosystem. The lake has been transformed from a typical coastal ecosystem to a brackish one. Since the dike completion, the lake has shown a similar change pattern to the Geum River estuary. Due to the salt-wedge intrusion of seawater, it is highly probable to expect the formation of low-oxygen zone at the bottom layer near the river-mouth area of the lake during the summer. Therefore we need a continuous sentinel monitoring of bottom water qualities in the near future.

• Journal of Agricultural Extension & Community Development
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• v.21 no.4
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• pp.1093-1124
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• 2014

Studies on the role of agricultural science colleges are mostly divided into agricultural production, which is the primary function of agriculture, and other functions, which have recently begun to be emphasized as a result of social needs. With the green revolution and the aging of the farming population, there is a strong view that the role of agricultural science colleges should remain as it is. However, agriculture is expanding in terms of concept and content by converging with other industries not traditionally associated with agricultural production. Thus, the fields that now need to form part of agricultural science knowledge are becoming more detailed and expansive. The government's perception remains at the level of merely fostering farmers. This was evident in a survey on the employment rate, a factor used to evaluate colleges, in which the role of agricultural science colleges was limited to fostering farmers. Agro- industry fields, other than agriculturalists, include general industries in which the academic fields of agricultural science are combined with other academic fields. Thus, even when someone is employed in an industry that requires background knowledge of agricultural science, there is often a perception that he or she is employed in a field that is irrelevant to the major. This study examines the role of agricultural science colleges in agriculture and farm villages by focusing on the employment of graduates of these colleges within agro-industry. We categorize academic research on agricultural science into 16 fields, based on the medium level of the National Standard Science and Technology Classification Codes. Then, we categorize the employment fields into 168 fields, based on the small classification level of the inter-industry relations classification. Thus, we investigate 220 departments of 37 colleges, nationwide. Our findings show that the average employment rate of graduates of agricultural science colleges is 69.0%. Furthermore, 33.0% of all employees work in agro-industry fields that require background knowledge in agricultural science, which is one out of three job seekers. Then, 3.6% of employees work in business startups in agro-industry. The aforementioned government survey showed that only 0.1% of all college graduates in Korea were employed as agriculturalists in 2013. However, our results showed that 13.3% of graduates were working as agriculturalists, which is significantly different to the results of the government survey. These results confirm that agricultural science colleges contribute greatly to the employment of graduates, including farmers, agro-industry, and business startups in agro-industry fields.

• Journal of Life Science
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• v.30 no.10
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• pp.905-911
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• 2020

The adjuvant effect of PAMAM dendrimer G4 (PAMAM) on the induction of humoral and cellular immune responses against keyhole limpet hemocyanin (KLH) was examined. Mice were immunized subcutaneously twice at two-week intervals with KLH, with or without PAMAM dendrimer (100 ㎍/mouse), and the mice immunized with KLH+PAMAM showed significantly higher antibody titers against KLH than those immunized with KLH alone. The assay for determining the isotypes of the antibodies showed that PAMAM augmented the KLH-specific antibody titers of IgG1, IgG2a, IgG2b, IgG3, and IgM. In addition, mice immunized twice with KLH+PAMAM followed by a subcutaneous injection of KLH (20 ㎍/site) 7 weeks after the primary immunization exhibited a higher delayed-type hypersensitivity (DTH) reaction than those treated with KLH alone. In an in vitro analysis of T lymphocyte proliferation in response to KLH in week 8, the splenocytes of mice treated with KLH+PAMAM showed significantly higher proliferating activity than those treated with KLH alone, and the culture supernatants of cell cultures from mice immunized with added PAMAM dendrimer showed higher levels of KLH-specific cytokine (IL-4 and IFN-r) production. These results suggest that PAMAM dendrimer G4 possesses a potent immune-adjuvant activity for enhancing both humoral and cell-mediated immunity specific to foreign antigens.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.10 no.1
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• pp.19-30
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• 2005

To investigate the seasonal distribution and grazing impacts of benthic protozoa in mud flat, their abundance, biomass and grazing rates of benthic protozoa were evaluated at interval of two or three month in Gangwha Island from April, 2002 to April, 2004. Heterotrophic flagellates and ciliates accounted for an average 98% of benthic protozoa biomass. Abundance and carbon biomass of heterotrophic flagellates ranged from $0.2{\times}10^5$ to $5.9{\times}10^5\;cells\;cm{-3}$ and from 0.02 to $9.2\;{\mu}gC\;cm^{-3}$, respectively. Biomass of heterotrophic flagellates was high in spring and fall, and showed no differences among stations. Abundance and biomass of heterotrophic flagellates decreased with the depth and were high within the surface 2.5 m sediment layer. The majority of heterotrophic flagellates were less than $10\;{\mu}m$ in length, and few euglenoid flagellates were larger than $20\;{\mu}m$. Abundance and carbon biomass of ciliates ranged from $0.1{\times}10^3$ to $17.8{\times}10^3\;cells\;cm^{-3}$ and from 0.02 to $9.1\;{\mu}gC\;cm^{-3}$, respectively, and those of ciliates were high in spring and fall. Biomass of ciliates was high within the surface 2.5 mm sediment layer and was higher at st. J2 and st. J3 than st. J1. Among the revealed benthic ciliates, the hypotrichs were the most important group in terms of abundance and biomass. During the sampling periods, an average 66% of benthic protozoa biomass was covered by ciliates. The seasonal distribution of benthic protozoa showed an almost similar fluctuation pattern to that of chlorophyll-a. The results suggest that the biomass of benthic protozoa were mainly controlled by prey abundance, for example, diatoms. Based on ingestion rates, benthic protozoa removed from 13.4 to 40.7% of bacterial production and from 20.1 to 36.4% of primary production. Ingestion rates of benthic protozoa on bacteria and microphytobenthos were high in April. Benthic protozoa in this study area may play a pivotal role in the carbon flow of the benthic microbial food web during spring.

• The Korean Journal of Mycology
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• v.31 no.2
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• pp.59-66
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• 2003

Laccase produced by Pycnoporus cinnabarinus SCH-3 isolated from Korea was partially purified using ultrafiltration, anion exchange chromatography and affinity chromatography, The laccase was produced as the predominant extracellular phenoloxidase during primary metabolism. Neither lignin peroxidase nor manganese-dependent peroxidase were detected in the culture fluid. In order to examine the effect of inducers in laccase production, 2,5-xylidine was added in the culture of Pycnoporus cinnabarinus SCH-3. Addition of 2,5-xylidine enhanced 25-fold laccase production. Purified laccase was a single polypeptide having a molecular mass of approximately 66 kDa, as determined by SDS-polyacrylamide gel electrophoresis, and carbohydrate content of 9%. $K_{m}\;and\;V_{max}$ values for laccase with ABTS [2,2-azinobis (3-ethylbenzthiazoline 6-sulfonic acid)] as a substrate (Lineweaver-Burk plot) was determined to be $44.4{\mu}M\;and\;56.0{\mu}mole$, respectively. The optimal pH for laccase activity was found to be 3.0. The enzyme was very stable for 1 hour at $60{\circ}C$. Half-life ($t_{1/2}$) of the enzyme was about 10 min at $80{\circ}C$. Spectroscopic analysis of purified enzyme indicated that the enzyme was typical of copper-containing protein. Substrate specificity and inhibitor studies for laccase also indicated to be a typical fungal laccase. The N-terminal amino acid sequence of the P. cinnabarinus SCH-3 laccase showed 94% of homology to the N-terminal sequences of laccases from P. cinnabarinus PB and P. coccineus.

• Korean Journal of Ecology and Environment
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• v.51 no.1
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• pp.105-123
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• 2018

Currently, satellite images act as essential and important data in water resources, environment, and ecology as well as information of geographic information system. In this paper, we will investigate basic characteristics of satellite images, especially application examples in water resources. In recent years, researches on spatial and temporal characteristics of large-scale regions utilizing the advantages of satellite imagery have been actively conducted for fundamental hydrological components such as evapotranspiration, soil moisture and natural disasters such as drought, flood, and heavy snow. Furthermore, it is possible to analyze temporal and spatial characteristics such as vegetation characteristics, plant production, net primary production, turbidity of water bodies, chlorophyll concentration, and water quality by using various image information utilizing various sensor information of satellites. Korea is planning to launch a satellite for water resources and environment in the near future, so various researches are expected to be activated on this field.

• Journal of Korea Water Resources Association
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• v.42 no.11
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• pp.911-920
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• 2009

Virtual water is defined as the volume of water required to produce a commodity or service. The degree of food self-sufficiency is currently about 27 % in South Korea, so that Korea is one of the largest net virtual water import countries for agricultural product, thus it is necessary to estimate suitable virtual water for South Korea. The objective of this paper is to quantify the agricultural virtual water use (AWU) and virtual water content (VWC) using the method suggested by Chapagain and Hoekstra during the period 1991-2007. To calculate the virtual water content, 44 different crop production quantity and harvested area data were collected for 17 years and FAO Penman-Monteith equation was adapted for computing crop consumptive use of water. As the results, AWU has been estimated at 15.1 billion $m^3$ in average showing a tendency to decrease. Rice has the largest share in the AWU, consuming about 10.1 billion $m^3$/yr which is about 75 % of gross AWU, and the VWC is 1600.1 $m^3$/ton for paddy rice. The largest VWCs of crops are oilseed and tuber crop, and the smallest are leaf and root vegetables. The primary crop production VWC can be used for calculating the VWC of various secondary products using the contribution ratio, therefore the results of this study are expected to be used as basic data for national agricultural water footprint.

• Korean Journal of Environment and Ecology
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• v.27 no.5
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• pp.561-570
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• 2013

Organic carbon distribution and carbon budget of a Pinus densiflora forest in the Songgye valley of Mt. Worak National Park were investigated. Carbon in above and below ground standing biomass, litter layer, and soil organic carbon were measured from May 2011 through April 2012. For the estimation of carbon budget, soil respiration was measured. The amount of carbon allocated to above and below ground biomass was 52.25 and 14.52 ton C $ha^{-1}$. Amount of organic carbon in annual litterfall was 4.71 ton C $ha^{-1}$. Amount of organic carbon within 50cm soil depth was 58.56 ton C $ha^{-1}$ 50cm-$depth^{-1}$. Total amount of organic carbon in this Pinus densiflora forest was estimated to 130.04 ton C $ha^{-1}$. Amount of organic carbon in tree layer, shrub and herb layer was 4.12, 0.10 and 0.04 ton C $ha^{-1}yr^{-1}$ and total amount of organic carbon was 4.26 ton C $ha^{-1}yr^{-1}$. Amount of organic carbon returned to the forest via litterfall was 1.62 ton C $ha^{-1}yr^{-1}$. The amount of carbon evolved through soil respiration was 6.25 ton C $ha^{-1}yr^{-1}$. The amount of carbon evolved through microbial respiration and root respiration was 3.19 and 3.06 ton C $ha^{-1}yr^{-1}$. The amount of organic carbon absorbed from the atmosphere of this Pinus densiflora forest was 1.07 ton C $ha^{-1}yr^{-1}$ when it was estimated from the difference between Net Primary Production and microbial respiration.

• Tuberculosis and Respiratory Diseases
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• v.47 no.4
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• pp.525-532
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• 1999

The parathyroid hormone related protein (PTHrP) is the most common causative peptide of humoral hypercalcemia of malignancy. In contrast, the serum level of parathyroid hormone (PTH) is low to undetectable in the majority of patients with malignancy associated hypercalcemia. Few cases exist in which the production and secretion of PTH by malignant nonparathyroid tumors have been authenticated. To our knowledge, there is very rare case in which a nonparathyroid tumor expressed simultaneously both the PTH and PTHrP. We report a case of squamous cell carcinoma of the lung with hypercalcemia which presented with simultaneous elevation of serum PTH and PTHrP. Severe hypercalcemia (serum calcium, 7.5 mEq/L) was found in a 65-year-old man who had a squamous cell carcinoma of the lung without any bony metastasis and detectable parathyroid abnormalities on isotope scintigraphy. The serum level of intact parathyroid hormone (PTH) con centration was markedly elevated as measured in two site radioimmunoreactive PTH assays (intact PTH 150 pg/mL ; normal 9~55). The serum level of a PTHrP was also increased as measured in C-terminal region specific radioimmunoassay (PTHrP 99.1 pmol/L; normal 13.8~55.3). There are no evidences of coincidental primary hyperparathyroidism in parathyroid MIBI scan and other imaging studies including neck ultrasonography and computed tomography. These results suggest that simultaneous elevation of serum PTH and PTHrP in this patient can be caused by production of both PTHrP and PTH in other nonparathyroid lesions such as squamous cell carcinoma.