• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.351-360
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• 2016

The purpose of this study is to predict visual-spatial working memory performance through the characteristics of an electroencephalogram (EEG) in the resting state. The 31 study participants, middle school students with various to academic performance, were underwent visual-spatial working memory test in the Comprehensive Attention Test (CAT) on December in 2014. Each 7 and 6 participants were divided into an Excellent Working Memory (EWM) group and Poor Working Memory (PWM) group depending on the forward/backward working memory scores. The EEG measurements and analysis of the data from a Brain Function Tester were performed by the two groups. A Mann-Whitney Test was used to examine the statistical differences between them. The activation of high beta (${\beta}H$) at the Fp1 and Fp2 sites in the left and right hemisphere, and that of the low beta (${\beta}L$) in the right hemisphere in the EWM group was significantly higher than that in the PWM group. In conclusion, there is a correlation between the visual-spatial working memory performance and the activation of ${\beta}H$ and ${\beta}L$ in the resting state and a close correlation that of ${\beta}L$ in the right hemisphere in terms of mental activity and faculty. Therefore, the visual-spatial working memory performance can be predicted by the activation of ${\beta}H$ and ${\beta}L$ in the resting state. The activation of EEG can be applied as an assessment tool and provide basis data for visual-spatial working memory performance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.4
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• pp.429-438
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• 2007

Early growth vigor(EGV) is one of the physiological characteristics that may contribute to the increase of genetic yield potential and radiation use efficiency by closing the canopy earlier. To estimate the genotypic variation of EGV, determine the relationships among the related traits, and identify the rapidly growing genotypes and indirect indicator for selection in breeding program, the evaluation of EGV and EGV-related traits was conducted for a total of 140 rice varieties consisting of 101 Korean, 25 Northern China and 14 IRRI-bred rice varieties in a serial sowing experiment in plastic rain shelter and plastic-covered nursery bed in 2003. EGV defined as the amount of leaf area and/or dry weight produced early in the season and the EGV-related traits such as length and breadth of the $2^{nd}\;and\;3^{rd}$ leaves showed highly significant positive correlation with the embryo and seed weight. Especially, the genotypic variation in the length of the third leaf was explained over 90% of genotypic variation in the seed weight. Owing to a large effect of seed size on EGV and its related traits, vigor measurements were adjusted based on their linear or exponential relationships with seed weight for excluding the seed weight effect. EGV and its related-traits adjusted for seed weight also showed big variation among genotypes. Increased EGV was genetically correlated with increases in breadth and length of early leaves. The broad-sense heritability for EGV was significantly high(81%), but lower than those of leaf breadth(90% for the $2^{nd}$ leaf and 93% for the $3^{rd}$ leaf) and length(87% for the $2^{nd}$ leaf and 89% for the $3^{rd}$ leaf). Significantly positive genetic correlations were found between EGV and the breadth and length of early leaves. The high heritability of early leaf breadth and length coupled with their strong genetic correlation with EGV indicated that the breadth and length of the $2^{nd}\;and\;3^{rd}$ leaf would be used as good indirect indicators for EGV selection in rice breeding program.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.2
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• pp.113-117
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• 2017

The purpose of this study was to evaluate the effects of rice cultivars (Hangaru, Seolgaeng, Dasan-1 and Anda) on the quality characteristics of rice beer. Hangaru and Seolgaeng which are soft rice varieties, had moisture contents that were 14.48% and 14.62% higher than those of Dasan-1 and Anda, respectively. Dasan-1 and Anda showed higher protein contents than those of the other two varieties. The amylose content of Hangaru was found to be 17.71% lower than that of the other varieties, whereas the reducing sugar content of Hangaru and Seolgaeng was higher than that of Dasan-1 and Anda. Hardness measurements for Hangaru and Seolgaeng were lower than those for Dasan-1 and Anda. Measurements of the alcohol content, pH and color of beers brewed using these rice cultivars revealed no significant difference among the cultivars. However, measurement results for bitterness showed that beers brewed with Hangaru and Seolgaeng had lower bitterness than did the beers brewed with Dasan-1 and Anda. The results of this study indicate that Hangaru and Seolgaeng can be considered as cultivars with brewing qualities suitable for rice beer.

• Journal of Food Hygiene and Safety
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• v.25 no.4
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• pp.395-401
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• 2010

This research was carried out as a survey on the contents of Lead (Pb) and Cadmium (Cd) in 5 type agricultural products unestablished safety guideline in Korea. The average levels of Pb: onion 0.010 mg/kg, cucumber 0.018 mg/kg, garlic 0.012 mg/kg, green pepper 0.027 mg/kg, sesame 0.029 mg/kg. The average levels of Cd: onion 0.006 mg/kg, cucumber 0.002 mg/kg, garlic 0.008 mg/kg, green pepper 0.011 mg/kg, sesame 0.024 mg/kg. The present result of this study showed that Pb and Cd contents in the whole samples were less than the maximum residual levels of the codex standard. The levels of exposure assessment for Pb and Cd by intake from vegetables and sesame were merely at $1.3{\times}10^{-4}$(mean) ~ $5.1{\times}10^{-4}$($95^{th}$ percentiles) ${\mu}$g/kg bw/day for Pb, $7.5{\times}10^{-5}$(mean) ~ $3.6{\times}10^{-4}$($95^{th}$ percentiles) ${\mu$}g/kg bw/day for Cd. The data from this research will be valuable source for database construction for science-based safety control and management for the trace metal contamination in food including agricultural products.

• Food Science of Animal Resources
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• v.24 no.4
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• pp.329-334
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• 2004

The objective of this study was to determine the effect of herb and bio ceramic complex supplementation on growth performance and meat quality characteristics in finishing pigs. Seventy-two crossbred (Landrace ${\times}$ Yorkshire ${\times}$ Duroc) pigs (78.98kg average initial body weight) were used in a 45 days growth assay. Dietary treatments included 1) Control (basal diet). 2) HBC (Herb and bioceramic complex) 0.1 (basal diet + 0.1％ Herb and bioceramic complex) and 3) HBC 0.2 (basal diet +0.2％ Herb and bioceramic complex). For overall period, ADG (Average Daily weight Gain), ADFI (Average Daily feed Intake) and ADG/ADFI increased in Control with no significant difference (p>0.05). Backfat thickness was not significantly different among the treatments (p>0.05). The total cholesterol, HDL (High Density Lipoprotein) cholesterol, LDL (Low Density Lipoprotein) cholesterol, LDL + VLDL (Very Low Density Lipoprotein) cholesterol, Triglyceride and Atherogenic index concentrations of serum in pigs fed HBC 0.2 diet were lower than those of pigs fed Control and HBC 0.1 diets without significant difference (p>0.05). L$\^$*/-, a$\^$*/-, and b$\^$*/- values of M. longissimus dorsi muscle were not significantly different among the treatments (p>0.05). The pH of pigs fed HBC 0.2 diet was significantly lower than that of pigs fed Control and HBC 0.1 diets (p<0.05). In conclusion, growth performance, cholesterol concentration in serum and meat quality were not affected by supplemental herb and bioceramic complex.

• Korean Journal of Environmental Agriculture
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• v.24 no.3
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• pp.222-231
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• 2005

Most of the tailings have been left without any management in abandoned metalliferous mines and have become the main source of heavy metal contamination of agricultural soils and crops in the these areas. To compare of environmental assessment of heavy metals in tailings derived from various 25-metalliferous mines in Korea, 3 different analysis methods such as water soluble, 0.1 M-HCl extractable, and total acid digestion method (aqua regia) were used. The chemical composition of water soluble in mine tailing were in the order ${SO_4}^{2-}>Ca^{2+}>Mn^{2+},\;Na^+,\;Al^{3+}>Mg^{2+},\;Fe^{3+}>Cl^-$. Specially, pH, EC, ${SO_4}^{2-},\;and\;Ca^{2+}$ concentrations in tailing varied considerably among the different mines. The average total concentrations of Cd, Cu, Pb, Zn, and As in tailing were 31.8, 708, 4,961, 2,275 and 3,235 mg/kg, respectively. Specially, the contents of Cd, Zn and As were higher than those of countermeasure values for soil contamination (Cd : 4, Zn : 700 and As : 15 mg/kg in soil) by Soil Environmental Conservation Act in Korea. The rates of water soluble heavy metals to total contents in tailings were in the order Cd > Zn > Cu > Pb > As. The rates of 0.1M-HCl extractable Cd, Cu, Pb, Zn, and As (1M-HCl) to total content were 17.4, 10.2, 6.5, 6.8 and 11.4% respectively. The enrichment factor of heavy metals in tailings were in the order As > Pb > Cd > Cu > Zn. The pollution index in tailing Au-Ag mine tailing were higher than those of other mine tailing. As a results of enrichment factor and pollution index for heavy metal contaminations in mine tailing of metalliferous mines, the main contaminants are mine waste materials including tailings.

• Journal of Aquaculture
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• v.11 no.4
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• pp.573-580
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• 1998

Red spotted grouper, Epinephelus akaara is distributed in the south and west coasts of Korea. The natural stocks of the fish are decreasing sharply year by uear because of reckless overfishing. This research was carried out to understand general informations on maturation, sex composition and sex-reversals of the fish. Annual fishing uields of red spotted grouper in the castal area of Byonsan Peninsular of Kora decreased over 10% from 1992 to 1994. The main fishing season was from May to July with fishing gear of Hand-lines. Gonadosomatic index (GSI) and condition factor were highest on early and late July, respectively, thus main spawning reriod was assumed from late July to early August. The relationship between total length (X) and body weight (Y) for wild adults was represented as a regression, Y=$0.0169X^{2.9705}$, ($r^2$=0.96). Frequency of sex of wild red spotted gouper showed that the number of female below 38cm in total length was more than that of male, and hermaphrodite mainly occurred from 28cm to 32cm in total length the frequency of male and female were almost same. Also hermaphrodite occurred mainly between 25~29cm. Sex reversal ration of the adults reared in a tank for a year with different sexual compositions revealted that the frequency of female reversed from male was more than that of male reversed from female at 1:1 and 1:2 stocking densities of female and male, respectively. Also, about 20% of female was reversed to male when all females were reared. And the size of the fish reversed to male was larger than that of non-reversed female.

• Journal of dental hygiene science
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• v.13 no.3
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• pp.223-229
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• 2013

The aim of this study was to examine the effectiveness of oral health promotion program in a group of 9~18-year-old children and adolescents living in four orphanages in Dong-gu, Daejeon. The program was based on oral disease prevention program including oral health education, fluoride application and scaling every six months. Oral health status of total 109 orphans was examined by one dentists who were trained in 2010 Korean National Oral Health Survey. Dental caries index, community periodontal index and modified patient hygiene performance index (M-PHP) were checked using dental unit chair. Child oral health impact profile (COHIP) and subjective oral health recognition survey were carried out. Compared with data of 2010 national sample, the mean of decayed, missing and filled teeth showed no difference between the subjects and test values, but the means of decayed teeth, decayed surface, toothbrushing frequency of the subjects showed to become worse with advancing years in spite of oral health promotion program. COHIP, subjective oral health status showed lower than test values, too. In M-PHP and Calculus index, the subjects showed better by periodic oral health education and scaling. We suggest that oral health promotion program for orphans include oral disease treatment program as well as preventive program to improve oral health of orphans efficiently. And, oral health promotion program has to be connected with psychological support for improving quality of life of orphans.

• Journal of dental hygiene science
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• v.13 no.3
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• pp.271-280
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• 2013

This study aims to analyze the effects of tooth-brushing facilities (TBF) at middle schools that installed TBF in 2012 as part of the oral health project in Seongdong-gu, Seoul. The subjects were the first graders at A middle school that installed TBF previously and B middle school that installed TBF in 2012. The results are as follows: DMFT, DMFS and CPI didn't show significant difference by schools (p>0.05), but code (0) was higher and code (2) was lower in female students than male students (p<0.05). As to PHP index, the students at A school with TBF indicated better oral hygiene (p<0.01). In the research on before and after installing TBF, the oral hygiene was improved significantly more after the installation than before (p <0.01). In the comparison on the oral health-related behavior, the percentage of not brushing after lunch was higher B school than A school and the frequency of toothbrushing after lunch was higher A school than B school (p<0.01). About the reasons why not to brush after lunch, there was difference in 'lack of the place' as A school showed 2.6% while B school without TBF indicated 14.2% (p<0.01). About the changes of the oral health-related behavior before and after TBF installation, the percentage of not brushing after lunch increased from 78.7% to 83.8% after the installation. The average frequency of tooth-brushing after lunch for one week also decreased from 0.50 to 0.34 (p>0.05). Among the reasons why not to brush after lunch, 'lack of the place' significantly reduced, but 'because other friends don't do it' increased greatly after the installation (p <0.05). Only with the improvement of oral health knowledge, we cannot expect either clinical or behavioral significance. Not only schools but policies of governmental agencies and financial support, cooperation of community-related groups for program development and evaluation will contribute altogether to helping teenagers to habitualize proper oral health management.

• Journal of Life Science
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• v.22 no.11
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• pp.1493-1499
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• 2012

The level of genetic variation and relationships in three native Korean goat populations (Dangjin, Jangsu, and Tongyeong) as well as the populations of a farm were analyzed, based on 30 microsatellite markers. A total of 277 distinct alleles were observed across the four goat populations, and 102 (36.8%) of these alleles were unique to only one population. The mean observed heterozygosity and polymorphism information content were calculated as 0.461~0.651 and 0.462~0.679, respectively. In the NJ tree constructed based on Nei's $D_A$ genetic distance, the four populations represented four distinct groups. However, the genetic distances between each Korean native goat population and the farm population were two times those among the three native Korean breeds. The genetic structure within the three Korean native goat populations was also investigated. Cluster analysis, using the STRUCTURE software, suggested three clusters. The molecular information of genetic diversity and relationships in this study will be useful for the evaluation, conservation, and utilization of native Korean goat breeds as genetic resources.