• The Korean Journal of Physiology and Pharmacology
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• v.8 no.6
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• pp.301-305
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• 2004

This study examined the effects of N-methyl-D-aspartate (NMDA), ${\alpha}-amino$-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) and kainate on basal and electrically-evoked release of acetylcholine (ACh) from the rat hippocampal and striatal slices which were preincubated with $[^3H]choline$. Unexpectedly, the basal and evoked ACh release were not affected at all by the treatment with NMDA $(3{\sim}100{\mu}M)$, AMPA $(1{\sim}100{\mu}M)$ or kainate $(1{\sim}100{\mu}M)$ in hippocampal slices. However, in striatal slices, under the $Mg^{2+}-free$ medium, $30{\mu}M$ NMDA increased the basal ACh release with significant decrease of the electrically-evoked releases. The treatment with $1{\mu}M MK-801 not only reversed the $30{\mu}M$ NMDA-induced decrease of the evoked ACh release, but also attenuated the facilitatory effect of $30\;{\mu}M$ NMDA on the basal ACh release. The treatment with either $30\;{\mu}M$ AMPA or $100\;{\mu}M$ kainate increased the basal ACh release without any effects on the evoked release. The treatment with $10{\mu}M$ NBQX abolished the AMPA- or kainate-induced increase of the basal ACh release. Interestingly, NBQX significantly attenuated the evoked release when it was treated with AMPA, although it did not affect the evoked release alone without AMPA. These observations demonstrate that in hippocampal slices, ionotropic glutamate receptors do not modulate the ACh release in cholinergic terminals, whereas in striatal slices, activations of ionotropic glutamate receptors increase the basal ACh release though NMDA may decrease the electrically-evoked ACh release.

• The Korean Journal of Mycology
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• v.40 no.3
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• pp.141-144
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• 2012

Total 50 species, 80 strains: Eighty strains of yeasts were isolated from wild flowers of Daejeon city and its surroundings in Korea. Isolated yeasts were identified by comparison of their PCR-amplified 18s rDNA V3 region or internal transcribed spacer-2 (ITS-2) genes with BLAST database. Among them, 32 species, 54 strains of yeasts were isolated and identified from wild flowers of Daejeon city, and Cryptococcus species were dominant yeasts. Furthermore, 18 species, 26 strains of yeasts were isolated and identified from wild flowers of Geumsan-gun and Nonsan-gun, Chungcheongnam-do in Korea, and also Candida species and Pseudozyma species were dominant yeasts.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.147-154
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• 2014

Consecutive pepper cultivation in plastic film houses may lead to salt accumulation because pepper is considered a heavy nutrient feeder. For this reason, appropriate methods of fertilizer application should be established. Thus, we investigated the effect of different intervals of side-dressing N and K fertilizer applications on soil and red pepper in a plastic film house. All the amounts of recommended compost and phosphorus fertilizer were applied as basal dressing. Cultivars of the pepper plant were Cheon-Ha-Dae-Se (CHDS) and NW-BiGaLim (NW-BGL). Nitrogen and potassium fertilizers were treated as side-dressing at different intervals, 22 times in every 10 days, 15 times in every 15 days, and 11 times in every 20 days. Soil pH decreased with decreasing the intervals of side-dressing applications, whereas electrical conductivity (EC) declined with the increasing fertilizer application intervals. In particular, EC value decreased by up to 75% with CHDS cultivar in the plot of 20 day-interval and with NW-BGL cultivar in the plot of 15 day-interval. The concentrations of available phosphorus in the soils increased with increasing the interval. The concentration of exchangeable $K^+$ increased but exchangeable $Ca^{2+}$ and $Mg^{2+}$ decreased in all the plots, except in the control plot. The concentrations of nitrogen and phosphorus in leaves of the pepper plants were lowest in the control plot. Potassium concentrations in the pepper leaves were high in the control plot and in the plots of CHDS with 10 day-interval and NW-BGL with 15 day-interval. Red pepper productivity was high in the plots of 10- and 15 day-intervals for CHDS cultivar and 15- and 20 day-intervals for NW-BGL cultivar. Therefore, the 15 day-interval of side-dressing N and K applications was considered as an appropriate method for cultivating pepper plants and protecting soil in plastic film houses.

• Journal of agriculture & life science
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• v.46 no.6
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• pp.173-184
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• 2012

The objectives of this study are to analyze the factors affecting the structural changes of agricultural land use in Gyeongsangnam-do and to prospect for its future use. Seven commodity groups are categorized to include all agricultural products: rice, summer food crops, summer vegetables and other cash crops, fruits, barley, winter field vegetables, and winter greenhouse vegetables. We developed a model for acreage distribution among the seven commodity groups, and estimated the economic relations between prices and acreage distribution. The results showed positive relations exist between cultivating acreage and own commodity prices in all commodity groups, whereas competitive relations exist between summer commodity groups or winter commodity groups such that rice price decreases led to increases of fruits cultivating acreage or vice versa and winter vegetable price increases led to increases of winter greenhouse vegetables cultivating acreage or vice versa. Further, acreage elasticities with respect to own commodity prices or farm wage rates are estimated over the last 30 years, and future agricultural land use in Gyeongsangnam-do is prospected based on three different scenarios. Total agricultural land use in Gyeongsangnam-do will be decreased over the next 10 years from 159,000 ha in year 2010 to 143,000~153,000 ha in year 2020. By commodity group, cultivating acreage of rice, summer food crops, and barley will be decreased while cultivating acreage of summer vegetables, fruits, winter field vegetables, and winter greenhouse vegetables will be stagnant.

• Research in Community and Public Health Nursing
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• v.27 no.3
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• pp.242-253
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• 2016

Purpose: This research aims to understand the perceptions of nursing homes from the perspective of the elderly, explores the themes of such perception and provides supporting evidence for developing nursing intervention that focuses on the subjects of care within nursing homes. Methods: This research is based on qualitative research in a phenomenological methodology. The research participants included elders aged 67~83 living at home in Jeonnam, Jeonbuk Provinces and G City. Data collection methodologies included in-depth interviews and observation of participants. The data were analyzed in the phenomenological methodology by Colaizzi. Results: As a result of the research, it was found that all significant statements about the Korean elders' perception of nursing homes fell within 3 categories with 9 major themes and 23 minor themes. The three observed categories for the Korean elders' perception on nursing homes were: 'places they do not like to be in', 'places they have to be in' and 'places that makes them feel fortunate as they have a place to go'. Conclusion: This research provides foundational tools that will provide a steer for changes in nursing environment, physiological support, programs and education so that the needs of the elderly can be met more sufficiently.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.8
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• pp.1019-1023
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• 2018

In this paper sensitivity analysis of temperature on special day electricity demand of land and Jeju Island is performed. The basic electricity demand per 3 hours is defined as electricity demand that reflects the GDP effect without the temperature influence. The temperature sensitivity per 3 hours is calculated through the relationship between special day electricity demand normalized to basic electricity demand and temperature. In the future, forecast error will be improved if the temperature sensitivity per 3 hours is applied to the special day load forecasting.

• Korean Journal of Materials Research
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• v.19 no.3
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• pp.125-131
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• 2009

In this report, the structural and optical properties of sol-gel derived $Mg_xZn_{1-x}O$ thin films upon changes in the composition and annealing temperature were investigated. The $Mg^{2+}$ content and the annealing temperature were varied in the range of $0{\leq}x{\leq}0.35$ and $400^{\circ}C{\leq}T{\leq}600^{\circ}C$, respectively. The films exhibited a hexagonal wurtzite structure of a polycrystalline nature. The optical transmittance exceeded 85% and the optical band gap of the film was tuned as high as 3.84 eV at a value of x = 0.35 (annealed at $400^{\circ}C$), which was evidently the maximum $Mg^{2+}$ content for the single-phase polycrystalline $Mg_xZn_{1-x}O$ thin films prepared in this experiment. The optical band gap and photoluminescence emission were tailored to the higher energy side while maintaining crystallinity without a significant change of the lattice constant.

• Journal of Powder Materials
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• v.17 no.3
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• pp.235-241
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• 2010

Mo nanopowder was synthesized by ball-milling and subsequent hydrogen-reduction of $MoO_3$ powder. To fabricate ultra fine grained molybdenum, two-step sintering and spark plasma sintering process were employed. The grain size of specimen by two-step sintering and spark plasma sintering was around $0.6\;{\mu}m$ and $0.4\;{\mu}m$, respectively. Mechanical properties of ultra fine grained Mo with relative density of above 90% were significantly improved at room and high temperatures comparing to commercial bulk Mo of 99% relative density. This result was mainly explained by the grain size refinement due to diffusion-controlled sintering.

• Journal of the Korean earth science society
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• v.44 no.4
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• pp.291-306
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• 2023

Shallow groundwater in rural areas is primarily polluted by agricultural activities. Nitrate-nitrogen is an indicator of artificial pollution. In this study, the hydrochemical characteristics and nitrate-nitrogen pollution of shallow groundwater were examined in two agricultural villages (Hyogyo-ri and Sinan-ri) in Chungcheongnam-do Province, Korea. Physicochemical quality analysis of shallow groundwater and stream water in the field, and chemical analysis in the laboratory were conducted from July 2020 to October 2021. In Hygyo-ri and Sinan-ri villages, shallow groundwater mainly belonged to the Ca-Cl, Ca-H CO₃, Na-HCO₃, and Na-Cl types, whereas stream water predominantly belonged to the Ca-HCO₃ type. The nitrate-nitrogen concentration in shallow groundwater varied depending on the season, displaying an increased concentration of nitrate-nitrogen in the dry season compared to the rainy season. Stream water may be influenced by runoff into villages from the surrounding area, although both shallow groundwater and stream water are affected by artificial pollution. In addition, the nitrate-nitrogen concentration in stream water was lower than that in shallow groundwater.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.330-330
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• 2017

The tallest culm length was observed in Geonganghongmi cultivar grown in coast area, and culm length was always taller in coast area than that of inland area among these three red rice cultivars. However, number of tiller per rice plant was not affected by different cultural area. Number of spikelets per panicle was much more increased in inland area. Regional difference in number of spikelets per panicle was only observed in Jeongjinju cultivar. Among these red rice cultivars, the highest brown rice yield was Jeongjinju rice cultivar having 702kg in inland area and 692kg in coast area, respectively. The $L^*$ values, which expresses the brightness, were in the range of 36.3 ~ 36.7, 36.7 ~ 37.0, and 38.7 ~ 39.6 in Jeogjinju, Hongjinju, Geonganghongmi rice cultivars, respectively. The $a^*$ values, which expresses the redness positively and greenness negatively were in the range of 12.3 ~ 12.8, 12.2 ~ 12.3, and 12.1 ~ 11.9 in Jeogjinju, Hongjinju, Geonganghongmi rice cultivars, respectively. In addition, the b values, which expresses the yellowness positively and blueness negatively were in the range of 13.8 ~ 14.0, 13.6 ~ 13.5, and 14.9 ~ 14.7 in Jeogjinju, Hongjinju, Geonganghongmi rice cultivars, respectively. Anthocyanidin content ranged 524 to $610{\mu}g/g$ dry weight basis. Cyanidin content was 11.4 to 14.0 times higher than that of delphinidin under coast and inland area. Among these rice cultivars, anthocyanidin content was always higher in rice cultivar grown at coast area. Highest head brown rice rate was only observed in Geonganghongmi to 95.2 at coast area and 95.4 inland area, respectively. Protein content was always higher in coast area than that of inland area. The lowest protein content was measured in Jeogjinju and amylose content was relatively increased in inland area compared to that of coast area. Consequently, in considered with brown rice yield and pigment content, Hongjinju rice cultivar was recommended in optimal pigment rice cultivar in eastern coast of Gyeongsangbuk-do Province.