• Reproductive and Developmental Biology
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• v.28 no.2
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• pp.127-132
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• 2004

This study was conducted to examine the effects of electric stimulation conditions on in vitro developmental ability of caprine embryos after somatic cell nuclear transfer. Recipient oocytes were surgically collected after superovulation by using CIDR and FSH, PMSG, hCG and estrous synchronization in Korean native goats. The caprine ear cells were cultured in vitro in serum-starvation condition (TCM-l99 + 0.5% FBS) for 3 to 5 days of cell confluence. The zona pellucida of in vivo and in vitro matured oocytes were partially drilled using laser system. Single somatic cell was individually transferred into the enucleated oocyte. The reconstructed oocytes were electrically fused with 0.3M mannitol. After the electofusion, embryos were activated by electric stimulation or Ionomycin + 6-DMAP. Nuclear transfer embryos were cultured in mSOF medium supplemented with 0.8% BSA 6∼7 days at 39 , 5% $CO_2$, 5% $O_2$, 90% $N_2$. The fusion rate of donor cells was 60.4% and 40.3 % in ear cell and fetal fibroblast, and cleavage rate were 40.6% and 48.2%, respectively. No significant difference was found in the fusion and cleavage rate in different donor cells. Nuclear transferred oocytes were fused by electric pulses of 1.30∼1.40, 2.30∼2.39 and 2.40∼2.46 ㎸/cm. There was no significant difference among different electric pulses in fusion rates (26.7, 34.8 and 43.8%). The cleavage rate was higher (p<0.05) in 1.30∼1.40 ㎸/cm (82.9%) than 2.30∼2.39 ㎸/cm (43.8%) and 2.40∼2.46 ㎸/cm. (51.8%). The fusion rates of recipient oocyte source were 1st (43.5% and 23.6%), 2nd (55.7％ and 39.2%) and 3rd (66.1% and 52.8%) in in vivo and in vitro oocytes. However, fusion ratee were significantly higher (p<0.05) in in vivo than in vitro oocyte. The cleavage rate of fused oocytes from in vivo and in vitro sources were 52.6% and 54.4%, respectively. No significant difference was found in the cleavage rate according to the recipient oocyte source. These results suggest that factors such as field pulse of electric stimulation and oocyte source could affect in vitro developmental ability of nuclear transplanted caprine oocytes.

• Research in Plant Disease
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• v.11 no.1
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• pp.28-34
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• 2005

This study was conducted to investigate the control possibility of garlic white rot causing severe yield losses of Allium species and cultivars using cultural practices such as optimal sowing date and burial depth, and lime application. Inoculum density in infested field soil was investigated at different soil depth, and that on the diseased plant debris was done. Inoculum density and recovery ratio of white rot pathogen of garlic was highly different between two species of Sclerotium cepivorum forming comparatively small sclerotia and Sclerotium sp. forming comparatively large ones. It was confirmed that S. cepivorum formed more sclerotia on bulbs of garlic than S. sp., and sclerotial recovery of S. cepivorum was higher than that of S. sp. Inoculum density of white rot pathogen in the infested field at garlic seeding period ranged from one to thirteen sclerotia per 30 g soil. Inoculum density of white rot pathogen decreased remarkably with increasing soil depth and above 95% of sclerotia were distributed within 5 cm of soil depth. Disease severity of white rot was higher on slightly planted garlics than deeply-planted ones. Garlic seed bulbs infected by white rot pathogens were confirmed to be one of main inoculum sources of white rot in the field and the disease incidences caused by garlic seed transmission showed big differences among garlic varieties. When nine garlic varieties harvested from infested plots were sown in the field, highly susceptible varieties, ‘Wando’, ‘Daeseo’, ‘Namdo’ and ‘Kodang’ showed high disease incidences, whereas other five varieties were not infected at all. It was confirmed that white rot occurred higher on early-sown garlics, before middle October, than on late-sown ones, after late October. Meanwhile, increasing application rate of lime ranged from 100 to 300 g reduced disease severity of white rot.

• Horticultural Science & Technology
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• v.31 no.1
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• pp.56-64
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• 2013

Recent unusual weather due to global warming causes shortage of daily sunlight and constitutes one of the primary reasons for agricultural damages. LED light sources are frequently utilized to compensate for the shortage of sunlight in greenhouse agriculture. The present study is aimed at evaluating formations of phytochemicals as well as growth characteristics of mature strawberry fruits ('Daewang' cultivar) during cultivation in a closed growth chamber equipped with artificial LED light as a sole light source. Each LED light of blue (448 nm), red (634 and 661 nm) or mixed blue plus red (blue:red = 3:7) was separately supplied and the intensity of each light was adjusted to $200{\pm}1{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at plant level with a photoperiod consisted of 16 hours light and 8 hours darkness. Strawberries grown under mixed LED light of blue and red wavelengths showed a higher production of fruits than those grown under other LED treatments. Fructose, one of the free sugars, increased in mixed LED light-grown fruits. Anthocyanin contents were elevated remarkably in the mixed LED light-grown fruits compared with those in other LED treatments. Contrastingly, contents of total phenolics and flavonoids were not of much different from one another among the fruits treated with various LED lights. On the other hand, ripening of strawberry fruits was found to be faster when grown under blue LED light compared with other LED treatments. Moreover, antioxidant activities of blue or red LED light-grown fruits, respectively, were significantly higher than those of mixed LED light-grown fruits. We suggest that when daylight is in shortage during cultivation in a greenhouse, supplementation of sunlight with LED light, which is composed of blue and red wavelengths, could be useful for the enhancement of productivity as well as of free sugar content in strawberry fruits. In addition, for the strawberry culture in the plant factory, selective adoption of LED light wavelength would be required to accomplish the purpose of controlling fruit maturation time as well as of enhancing contents of sugars and antioxidants of fruits.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.916-923
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• 1998

To provide more information on the enteric pathogen Campylobacter jejuni in the view of food sanitation, survival characteristics of two strains of C. jejuni in the different conditions were investigated. When $10^7{\;}or{\;}10^3{\;}per{\;}ml$ of C. jejuni cells were inoculated in the supplemented Brucella broth and kept at $42^{\circ}C,{\;}25^{\circ}C{\;}and{\;}5^{\circ}C$ under the static aerobic condition for 7 days, organisms exponentially proliferated to $a{\;}>10^8$, even in the $10^3{\;}per{\;}ml$ inoculated-sample at $42^{\circ}C{\;}for{\;}1{\sim}2{\;}days$ and the considerable level of viability maintained during 7 days. At $5^{\circ}C$, most of the initial level of organisms survived at the early period and only $a{\;}<{\;}0.5-log_{10}$ cells decrease were observed during the 7 days. At $25^{\circ}C$, a remarkable number of C. jejuni declined within $1{\sim}2{\;}days$ and showed undetectable level of cells after 4 days. When sterile milk and minced chicken meat were artifically inoculated with $10^7{\;}per{\;}ml$ of C. jejuni, mostly, a $1-to{\;}2-log_{10}$ count decrease occurred at $42^{\circ}C{\;}and{\;}5^{\circ}C$ while $a{\;}>3{\;}log_{10}$ decrease at $25^{\circ}C$ during 7 days. Unexpectedly, no colonies appeared on the plate inoculated from the minced chicken meat sample kept at $42^{\circ}C$ after 4 days. The results suggest that C. jejuni contaminated to food can survive at the refrigeration temperature whereas they are sensitive to at the room temperature. Also, it is shown that the growth of C. jejuni at the optimal temperature may vary to the food sources.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.3
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• pp.73-82
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• 2021

Rural roads are the significant infrastructure for developing and managing the rural areas, hence the utilization of the remote sensing datasets for managing the rural roads is necessary for expanding the rural transportation infrastructure and improving the life quality of the rural residents. In this research, the two different methods such as image classification and image segmentation were compared for mapping the rural road based on the given high-resolution satellite image acquired in the rural areas. In the image classification method, the deep learning with the multiple neural networks was employed to the given high-resolution satellite image for generating the object classification map, then the rural roads were mapped by extracting the road objects from the generated object classification map. In the image segmentation method, the multiresolution segmentation was employed to the same satellite image for generating the segment image, then the rural roads were mapped by merging the road objects located on the rural roads on the satellite image. We used the 100 checkpoints for assessing the accuracy of the two rural roads mapped by the different methods and drew the following conclusions. The image segmentation method had the better performance than the image classification method for mapping the rural roads using the give satellite image, because some of the rural roads mapped by the image classification method were not identified due to the miclassification errors occurred in the object classification map, while all of the rural roads mapped by the image segmentation method were identified. However some of the rural roads mapped by the image segmentation method also had the miclassfication errors due to some rural road segments including the non-rural road objects. In future research the object-oriented classification or the convolutional neural networks widely used for detecting the precise objects from the image sources would be used for improving the accuracy of the rural roads using the high-resolution satellite image.

• Journal of Internet Computing and Services
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• v.24 no.2
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• pp.19-26
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• 2023

Humans have adapted and evolved to natural light. However, as humans stay in indoor longer in modern times, the problem of biorhythm disturbance has been induced. To solve this problem, research is being conducted on lighting that reproduces the correlated color temperature(CCT) of natural light that varies from sunrise to sunset. In order to reproduce the CCT of natural light, multiple LED light sources with different CCTs are used to produce lighting, and then a control index DB is constructed by measuring and collecting the light characteristics of the combination of input currents for each light source in hundreds to thousands of steps, and then using it to control the lighting through the light characteristic matching method. The problem with this control method is that the more detailed the steps of the combination of input currents, the more time and economic costs are incurred. In this paper, an LED lighting control method that applies interpolation and combination calculation based on the minimum spectral power distribution information for each light source is proposed to reproduce the CCT of natural light. First, five minimum SPD information for each channel was measured and collected for the LED lighting, which consisted of light source channels with different CCTs and implemented input current control function of a 256-steps for each channel. Interpolation calculation was performed to generate SPD of 256 steps for each channel for the minimum SPD information, and SPD for all control combinations of LED lighting was generated through combination calculation of SPD for each channel. Illuminance and CCT were calculated through the generated SPD, a control index DB was constructed, and the CCT of natural light was reproduced through a matching technique. In the performance evaluation, the CCT for natural light was provided within the range of an average error rate of 0.18% while meeting the recommended indoor illumination standard.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.1-12
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• 2008

The purpose of this study is to characterize the hydrogeochemical characteristics of hot spring waters and to interpret the source of noble gases and the geochemical environment of the hot spring waters distributed along the eastern area of the Korean peninsula. For this purpose, We carried out the chemical, stable isotopic and noble gas isotopic analyses for eleven hot spring water and fourteen hot spring gas samples collected from six hot spring sites. The hot spring waters except the Osaek hot spring water show the pH range of 7.0 to 9.1. However, the Osaek $CO_2$-rich hot spring water shows a weak acid of pH 5.7. The temperature of hot spring waters in the study area ranges from $25.7^{\circ}C$ to $68.3^{\circ}C$. Electrical conductivity of hot spring waters varies widely from 202 to $7,130{\mu}S/cm$. High electrical conductivity (av., $3,890{\mu}S/sm$) by high Na and Cl contents of the Haeundae and the Dongrae hot spring waters indicates that the hot spring waters were mixed with seawater in the subsurface thermal system. The type of hot springs in the viewpoint of dissolved components can be grouped into three types: (1) alkaline Na-$HCO_3$ type including sulfur gas of the Osaek, Baekam, Dukgu and Chuksan hot springs, and (2) saline Na-Cl type of the Haeundae and Dongrae hot springs, and (3) weak acid $CO_2$-rich Na-$HCO_3$ type of Osaek hot spring. Tritium ratios of the Haeundae and the Dongrae hot springs indicate different residence time in their aquifers of older water of $0.0{\sim}0.3$ TU and younger water of $5.9{\sim}8.8$ TU. The ${\delta}^{18}O$ and ${\delta}D$ values of hot spring waters indicate that they originate from the meteoric water, and that the values also reflect a latitude effect according to their locations. $^3He/^4He$ ratios of the hot spring waters except Osaek $CO_2$-rich hot spring water range from $0.1{\times}10^{-6}$ to $1.1{\times}10^{-6}$ which are plotted above the mixing line between air and crustal components. It means that the He gas in hot spring waters was originated mainly from atmosphere and crust sources, and partly from mantle sources. The Osaek $CO_2$-rich hot spring water shows $3.3{\times}10^{-6}$ in $^3He/^4He$ ratio that is 2.4 times higher than those of atmosphere. It provides clearly a helium source from the deep mantle. $^{40}Ar/^{36}Ar$ ratios of hot spring water are in the range of an atmosphere source.

• Korean Journal of Organic Agriculture
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• v.17 no.3
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• pp.371-380
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• 2009

This study was conducted to assess effects of supplying different types of nitrogen sources as fertilizers on productivity and feed values of barley and rye as winter forage crops, and ultimately done to get good quality of organic forages with higher fertilization of soil. For barley, N+P+K plots were significantly (P<0.05) higher in annual dry matter (DM) and total digestible nutrients (TDN) yields than other plots. However, cattle manure plots had significantly (P<0.05) higher annual DM and TDN than P+K and non-fertilizer plots. Plots of 50%-cattle manure and mixed sowing with hairy vetch or forage pea were higher than only 50%-cattle manure plot, particularly, these were significantly higher than non-fertilizer, and their crude protein (CP) yields were much higher than other plots. Crude protein contents were significantly higher in N+P+K and 50%-cattle manure slurry plots than non-fertilizer and P+K plots, and plots of mixed sowing with hairy vetch or forage pea in application of 50%-cattle manure had higher CP content than other plots. ADF content was lowest in 50%-cattle manure+forage pea plots, but highest in 100%-cattle manure plots. NDF content was lowest in legumes-mixed sowing, but highest in 100%-cattle manure plots. TDN content was the highest in forage pea plots, and plots of 50%-cattle manure and legumes-mixed sowing had high RFV, but cattle manure plots rich in ADF and NDF content had the lowest TDN and RFV. For rye, plots of 50%-cattle manure+hairy vetch mixed sowing, and N+P+K application had significantly higher annual DM, CP and TDN than other plots except for cattle manure. DM productive efficiency to nitrogen fertilization was markedly higher for cattle manure plots than for chemical fertilizer. This tendency was more conspicuous in plots of 50% cattle manure+legumes-mixed sowing. CP content was higher for N+P+K plot than for all plots, and plots of 50%-cattle manure + legumes-mixed sowing were significantly higher than other plots. On the contrary, forage pea-mixed sowing plot had the lowest ADF and NDF, but TDN and RFV were significantly (P<0.05) higher than other plots. Grass crop cultivation together with legumes by applying livestock manure to soil may lead to higher palatability of livestock, and better quality of forage. Furthermore, cattle manure application increased production yield per ha and CP contents. Thus, when applying forage crops produced by cattle manure application and mixed sowing to organic livestock production, it was conceived that forages produced might become a substitute for foreign organic grain as protein sources.

• Korean Journal of Organic Agriculture
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• v.21 no.3
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• pp.451-465
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• 2013

This study was conducted to estimate Hanwoo carrying capacity when whole crop barley, rye, wheat and tritcale as winter forage crops was grown on different applying sources (chemical fertilizer, cattle or organic fertilizer) and mixed sowing combination with hairy vetch or forage pea during the period of 2011~2012. The experimental plots within whole crop barley or rye were consisted of 7 treatments, which were non-fertilizer, chemical fertilizer (P+K), chemical fertilizer (N+P+K), organic fertilizer, cattle slurry, cattle slurry with hairy vetch, and cattle slurry with forage pea. Each plot was triplicates and experimental treatments were allocated in the randomized complete block design. For whole crop barley, annual mean dry matter (DM) and total digestible nutrients (TDN) yields were the highest in N+P+K plots, but there were no significant differences among organic fertilizer, cattle slurry and mixed sowing with legumes. The TDN were the highest in mixed sowing plots of forage pea plus cattle slurry application. As 450 kg Hanwoo heifers were fed diets included 70% whole crop barley, organic fertilizer, cattle slurry application and mixed sowing plots of forage pea is capable of raising average 2.8 to 3.1 heads/ha a year. For whole crop rye, annual mean DM were the highest in N+P+K plots, but there were no significant differences among cattle slurry. Organic fertilizer application significantly increased TDN and relative feed value (RFV) in comparison with treatments of N+P+K fertilization as chemical fertilizers. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 2.8~ 3.2 heads/ha a year. For whole crop wheat, annual DM, crude protein, and TDN yields of application groups and mixed sowing treatment with legumes showed 6.90~7.44, 0.53~0.60 and 4.35~5.04 ton/ha, respectively. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.1~3.7 heads/ha a year. For Triticale, TDN yield was significantly (P<0.05) higher N+P+K plots, organic ferilizer, cattle slurry, cattle slurry with legumes than for no fertilizer and N+P+K plots. The Crude protein (CP) contents were the highest in mixed sowing plots of forage pea plus cattle slurry application. In case of 450 kg Hanwoo heifers fed diets included 70% forage triticale, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.4~3.7 heads/ha a year. It can be concluded that, on the basis of DM yield, not only mixed sowing with legumes by applying cattle slurry rather than single sowing of whole crop barley or whole crop rye enhanced production yield and feed values, but also it could be a substitute for imported grains as dietary protein sources in the case of feeding Hanwoo.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.659-666
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• 2005

The purpose of this study was to compare the intake status of calcium, phosphorus, iron, and zinc of Korean adults residing in different regions. Subjects were recruited and divided into three groups according to the districts where they lived, which included rural (n=137), coastal (n=100), and urban district (n=117). Subjects were interviewed using a general questionnaire and 24-hour recall method for dietary intake. The average age of the subjects were 58.1 years for rural district, 57.7 years for coastal district, and 48.6 years for urban district. There was no significance in total food intake by regions. The food intakes from cereals, mushrooms, vegetables of rural district, that from fishes of coastal district, and those from sugars, milks, oils of urban area were the highest among three districts. The calcium, phosphorus, iron, and zinc intakes were $60.1\%,\;123.9\%,\;95.2\%,\;and\;73.1\%$ of RDAs, respectively. The calcium intakes as percentage of RDA in rural and coastal district were significantly (p<0.01) lower than that in urban district. A larger number of subjects from coastal or urban district ate under $75\%$ of zinc RDA compared to those from rural village. Major sources of dietary calcium in total subjects were anchovy, kimchi, milk, soybean curd, rice, ice cream, sea mustard, yogurt, loach, and welsh onion. Rice supplied $15.5\%$ for phosphorus, $22.1\%$ for iron, and $35.9\%$ for zinc of total intake. Except for rice, major sources of dietary zinc were pork, beef, small red bean, dog meat, chicken, jacopever, soybean curd, glutinous millet, and kimchi. In conclusion, the food and mineral intakes of adults differed according to the regions in which they resided. The food and nutrient intakes of coastal district were not satisfactory, and calcium and zinc intakes of three regions did not meet RDAs. Therefore, it is required unique and discriminatory nutritional education with each region for increasing intakes of calcium and zinc.