• The Plant Pathology Journal
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• v.31 no.4
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• pp.379-387
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• 2015

Melon necrotic spot virus (MNSV) was recently identified on watermelon (Citrullus vulgaris) in Korea, displaying as large necrotic spots and vein necrosis on the leaves and stems. The average occurrence of MNSV on watermelon was found to be 30-65% in Hapcheon and Andong City, respectively. Four isolates of the virus (MNSV-HW, MNSV-AW, MNSV-YW, and MNSV-SW) obtained from watermelon plants in different areas were non-pathogenic on ten general indicator plants, including Chenopodium quinoa, while they infected systemically six varieties of Cucurbitaceae. The virus particles purified by 10-40% sucrose density gradient centrifugation had a typical ultraviolet spectrum, with a minimum at 245 nm and a maximum at 260 nm. The morphology of the virus was spherical with a diameter of 28-30 nm. Virus particles were observed scattered throughout the cytoplasm of watermelon cells, but no crystals were detected. An ELISA was conducted using antiserum against MNSV-HW; the optimum concentrations of IgG and conjugated IgG for the assay were $1{\mu}l/ml$ and a 1:8,000-1:10,000 dilutions, respectively. Antiserum against MNSV-HW could capture specifically both MNSV-MN from melon and MNSV-HW from watermelon by IC/RT-PCR, and they were effectively detected with the same specific primer to produce product of 1,172 bp. The dsRNA of MNSV-HW had the same profile (4.5, 1.8, and 1.6 kb) as that of MNSV-MN from melon. The nucleotide sequence of the coat protein of MNSV-HW gave a different phylogenetic tree, having 17.2% difference in nucleotide sequence compared with MNSV isolates from melon.

• Journal of People, Plants, and Environment
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• v.22 no.5
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• pp.411-424
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• 2019

This study analyzed the factors affecting urban residents' expectations and participation in community gardens to present basic data of guidelines for community garden management. Urban citizens valued the necessity of community gardens overall, especially residents with outdoor gardens. The experience of private gardens was important in perceiving the need for community gardens, which are public spaces. The creation of community gardens had high expectations for social aspects such as improving quality of life, health promotion, and community revitalization. In particular, residents living in individual housing have high expectations for revitalization of the community, and community gardens can be a mediator for forming and maintaining local communities. Through this, the citizens' perception on the role and function of the garden as a community space could be examined. Expectations for quality of life, health promotion, and community revitalization are factors affecting the necessity of community garden. Participation was high in the creation and management of the community garden, and the necessity of community gardens, expectation for community revitalization, and expectation for environmental purification are factors that affect participation in the management of community gardens. The amount of donations that the residents are willing to pay for community garden management was KRW 75,222 /year on average. Overall, residents with higher need for community gardens and higher social expectation showed higher participation. Urban citizens have high expectations for community gardens, and they perceive the importance of social aspects more than personal aspects such as community revitalization and quality of life. As a strategy for increasing community involvement, it is necessary to set up the processes, determine participants' composition and roles, and establish a system to promote participation. Considering welfare aspects such as community revitalization and improvement of residents' quality of life, motivation and administrative support for participation in the creation and management of community gardens will serve as important factors.

• Korean Chemical Engineering Research
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• v.52 no.6
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• pp.796-806
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• 2014

The key for the commercial deployment of IGCC power plants or chemical (methanol, dimethyl ether, etc.) production plants based on coal gasification is their economic advantage over plants producing electricity or chemicals from crude oil or natural gas. The better economy of coal gasification based plants can be obtained by co-production of electricity and chemicals. In this study, we carried out the economic feasibility analysis on the process of co-producing electricity and DME (dimethyl ether) using coal gasification. The plant's capacity was 250 MW electric and DME production of 300,000 ton per year. Assuming that the sales price of DME is 500,000 won/ton, the production cost of electricity is in the range of 33~58% of 150.69 won/kwh which is the average of SMP (system marginal price) in 2013, Korea. At present, the sales price of DME in China is approximately 900,000 won/ton. Therefore, there are more potential for lowering the price of co-produced electricity when comparing that from IGCC only. Since the co-production system can not only use the coal gasifier and the gas purification process as a common facility but also can control production rates of electricity and DME depending on the market demand, the production cost of electricity and DME can be significantly reduced compared to the process of producing electricity or DME separately.

• Korean Journal of Plant Resources
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• v.28 no.2
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• pp.158-167
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• 2015

We selected 8 plants among 11 Jeju native plants to search useful natural anti-oxidants by determining the amount of total polyphenols and the various anti-oxidative effects. Ethyl acetate extracts of Castanopsis sieboldii (Makino) Hatus. and butanol extracts of Oenothera laciniata Hill showed strong DPPH free radical scavenging effect. The IC₅₀ value of each solvent extract was 1.6 ㎍/㎖ and 2.4 ㎍/㎖, respectively. The ethyl acetate fraction of Castanea crenata Siebold & Zucc exhibited strong inhibition against nitric oxide production. For the inhibition of xanthine oxidase, the ethyl acetate extracts of Castanea crenata Siebold & Zucc showed strong inhibition activity with 16 ㎍/㎖ of its IC₅₀. The ethyl acetate extracts from Castanopsis sieboldii (Makino) Hatus showed strong superoxide scavenging effect with 7 ㎍/㎖ of its IC₅₀. The hydroxyl radical scavenging activity of butanol extract of Castanopsis sieboldii (Makino) Hatus was 76%. Therefore, with more researches on purification and identification of active compounds, plants studied are expected to be natural sources for the functional food/cosmeceuticals with anti-oxidative properties.

• Food Science and Biotechnology
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• v.17 no.3
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• pp.489-494
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• 2008

In order to develop a potent antidementia $\beta$-secretase inhibitor from phytochemicals, $\beta$-secretase inhibitory activities of extracts from many medicinal plants and herbs were determined. Water extracts from Rubus coreanus showed the highest $\beta$-secretase inhibitory activity of 84.5%. After purification of the $\beta$-secretase inhibitor from R. coreanus using systematic solvent extraction, ultrafiltration, Sephadex G-10 column chromatography, and reverse-phase high performance liquid chromatography (HPLC), a purified $\beta$-secretase inhibitor with $IC_{50}$ inhibitory activity of $6.3{\times}10^3\;ng/mL$ ($1.56{\times}10^{-6}\;M)$ was obtained with a 0.08% solid yield. The molecular mass of the purified $\beta$-secretase inhibitor was estimated to be 576 Da by liquid chromatography-mass spectrometry (LC-MS) and $\beta$-secretase inhibitor also is a new tetrapeptide with the sequence Gly-Trp-Trp-Glu. The purified $\beta$-secretase inhibitory peptide inhibited $\beta$-secretase non-competitively and also show less inhibition on trypsin, however no inhibition on other proteases such as $\alpha$-secretase, chymotrypsin, and elastase.

• Korean journal of applied entomology
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• v.16 no.1 s.30
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• pp.65-67
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• 1977

Yield losses from rice dwarf virus infection are significant in Korea. Rice dwarf virus(RDV) was purified and RDV-antiserum was produced. The purified virus, mixed with an adjuvant(1:1) was injected every 10 to 14 days into rabbits. Three injections .were sufficient to produce an antiserum of 1/4,096 titer. The produced antisera will be used to facilitate the detection and identification of RDV in rice plants and in the RDV leafhopper vectors.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.139.2-140
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• 2003

Ornithogalum showing mosaic symptoms were collected from the isolated field of National Plant Quarantine Service in Sengrimmyon of Kyungnam province. Electron microscopic examination of negatively strained preparation was filamentous particle of 740nm in lenght. Indirect-ELISA determined that the virus was serologically related to potyvirus. A single major protein band of Mr 30,000 was observed after sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Indicator plant test showed masaic, necrotic local lesion and sunken areas in leaves of Nicotiana clevelandii and Tetragonia expansa, while the others of indicator plants did not infect. An enzyme-aided purification protocal was used, which eliminated a highly viscous mucilage from extracts of the Omithogalum. Total RNA extracted from infected Omithogalum leaves were amplified of 411b.p fragment in reverse transcription (RT)-PCR when primers specilic for the coat protein gene. An isolate of Omithogalum mosaic virus (OrMV) of the genus Potyvirus was identified as the casual agent of the disease on the basis of electron microscopic, biological and serological reaction.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.744-748
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• 2000

The characteristics of $CO_2$ exchange between plant and human modules, absorption rate of NO$_2$, and growth of lettuce were examined in an urban-type plant factory(UPF). With 150 lettuce plants, $CO_2$ concentrations of plant module were 600 ~ 700$\mu$mol mol$^{-1}$ at average leaf weight of 130g.plant$^{-1}$ and 900~1100$\mu$mol.mol$^{-1}$ at 75g.plant$^{-1}$ for one and two persons' stay in the human module, respectively. When the air of 0.13, 0.30 and 0.45 $\mu$molㆍmol$^{-1}$ NO$_2$ in a human module was circulated ON/OFF 10/20min between the human and plant modules, $NO_2$ decrement in the chamber during 10 min was 0.040, 0.109, and 0.149 $\mu$mol, respectively. The lettuces grown at 0.45 $\mu$molㆍmol$^{-1}$ $NO_2$ during experimental period showed no significant differences in growth factors such as leaf width, leaf length, leaf area and fresh weigh, and in the quality between treated and control.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.1
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• pp.119-123
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• 2005

In the courses of in vitro screening for the angiotensin converting enzyme (ACE) inhibitory activity of the various extracts from medicinal plants, n-BuOH soluble extract of the seeds of Xanthium strumarium was found to exhibit distinctive angiotensin converting enzyme (ACE) inhibitory activity. Bioassay-guided fractionation and purification of the n-BuOH soluble extract of the seeds of Xanthium strumarium afforded a new $xanthiazone-11-{\beta}-glucopyranoside$. The ACE activity was significantly inhibited by the addition of a new $xanthiazone-11-{\beta}-glucopyranosidein$ a dose-dependent manner of which $IC_{50}$ value was $21.8\;{\mu}g/ml$.

• Journal of Korean Society of Water and Wastewater
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• v.11 no.1
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• pp.109-118
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• 1997

In this study, we examined the structural analysis of water demand fluctuation for water distribution control of water supply network. In order to analyze for the length of stationary time series, we calculate autocorrelation coefficient of each case equally divided data size. As a result, it was found that, with the data size of around three months, any case could be used as stationary time series. we analyze cross-correlation coefficient between the daily water consumption's data and primary influence factors. As a result, we have decided to use weather conditions and maximum temperature as natural primary factors and holidays as a social factor. Applying the multiple ARIMA model, we obtains an effective model to describe the daily water demand prediction. From the forecasting result, even though we forecast water distribution quantity of the following year, estimated values well express the flctuations of measurements. Thus, the suitability of the model for practical use can be confirmed. When this model is used for practical water distribution control, water distribution quantity for the following day should be found by inputting maximum temperature and weather conditions obtained from weather forecast, and water purification plants and service reservoirs should be operated based on this information while operation of pumps and valves should be set up. Consequently, we will be able to devise a rational water management system.