• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.2
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• pp.137-144
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• 2002

To investigate the short-term effects of N-supply form ( $NO_3\;^-$ or $NH_4\;^+$ ) and their level (0.2, 1.0 and 6.0 mM) on N assimilation and C metabolism were examined in perennial ryegrass (Lolium perenne L.). The increase in shoot fresh for $NH_4\;^+$-fed plants much less than $NO_3\;^-$ fed ones. Nitrate concentration in $NO_3\;^-$ -fed plants tended to increase with increasing the supply level, while that of $NH_4\;^+$-fed plants was nearly stable. Nitrate reductase activity (NRA) responded much quickly, showing a proportional increase within 24 h of feeding. NRA in $NO_3\;^-$ -fed plants at 72 h increased by 13.7, 40.3 and 84.0% in 0.2, 1.0 and 6.0 mM $NO_3\;^-$ -fed, but it was not changed in$NH_4\;^+$-fed plants regardless of the supply level. After 72 h of treatment the sugar accumulation in the plants supplied with 0.2 and 1.0 mM -$NH_4\;^+$fed was remarked. After 72 h of feeding, fructan hydrolysis was observed in all levels fur $NH_4\;^+$-fed plants, but only in 6.0 mM for $NO_3\;^-$ -fed plants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.2
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• pp.145-152
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• 2002

To compare the Carbon metabolic response to high temperature stress in Zoysiagrass [Zoysia matrella (L.) Merr.] and Creeping bentgrass (Agrostis palustris Huds) with respect to heat tolerance, C metabolites were determined from April to September. Sampling was carried out on an established golf course (Muan Country Club, Chonnam, Korea). Shoot mass(g Dry weight per hole cup) of creeping bentgrass started to decrease from June and recovered from August whereas that of zoysiagrass was less varied. Chlorophyll content in creeping bentgrass was significantly higher than zoysiagrass until July, and then decreased by 43% from July to August. Zoysiagrass contained higher soluble sugar than creeping bentgrass throughout experimental period. Soluble sugar in zoysiagrass increased about 58% from April to May, and less varied until August. Soluble sugar in creeping bentgrass slightly increased until July and sharply decreased at August. Starch concentration in zoysiagrass continuously decreased to September after a significant increase from April to May. A remarkable fluctuation in both starch and fluctuation concentration was observed between June and August showing high accumulation for June to July and high degradation for July to August. These results suggest that through creeping bentgrass suffers much severely from high temperature stress than zoysiagrass especially June to August. An active accumulation and degradation in nonstructural carbohydrate in creeping bentgrass during this period might be associated with heat stress.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.153-160
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• 2002

To investigate the effects of the exogenous N $O_3$$^{[-10]}$ supply level on the nitrate assimilation and growth during the vegetative growth stage, and on the accumulation of organic reserves during the successive regrowth period, dry matter (DM), the amount of nitrogenous compounds, total N and starch in alfalfa plants grown hydroponically with 0.2, 1.0 and 3.0 mM KN $O_3$ was estimated, respectively, during vegetative growth period and two cycle of regrowth. When compared with DMs and N contents in various N compounds in the organs grown with 1.0 mM N $O_3$$^{[-10]}$ , N starvation symptoms were found in 0.2 mM and a depressive effect was observed in 3.0 mM after 10 weeks of vegetative growth. Total starch content in root system gown with 0.2, 1.0 and 3.0 mM N $O_3$$^{[-10]}$ during the first regrowth was 50.96, 15.47 and 6.37 mg plant$^{-1}$, respectively. Starch was contained mainly in taproots. The starch content was not significantly changed by 24 days of the second regrowth with 1.0 mM N $H_4$N0$_3$. Total nitrogen content in root system grown with 0.2, 1.0 and 3.0 mM N $O_3$$^{[-10]}$ during the first regrowth was 6.66, 8.43 and 11.09 mg plant$^{-1}$ , respectively. Nitrogen was contained mainly in lateral roots; 80% (in 0.2 mM), 74% (1.0 mM) and 76% (3.0 mM) of total nitrogen in root system. Total N content in root system at the end of the second regrowth also closely affected by the N $O_3$$^{[-10]}$ supply level during the first regrowth. These results suggest that the level of N $O_3$$^{[-10]}$ may strongly influence the accumulation of organic reserves in root system, and that the initial level of organic reserves for the successive regrowth was one of the determinants for shoot regrowth.

• Journal of The Korean Society of Grassland and Forage Science
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• v.33 no.2
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• pp.81-86
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• 2013

'Mogwoo', a new high yield and whole crop silage rice (Oryza sativa L.) cultivar, was developed by the rice breeding team of the National Institute of Crop Science, RDA, Suwon, Korea, from 1999 to 2009, and was released in 2010. It was derived in 1999 from a cross between Dasanbyeo, having a high yield, and Suweon431/IR71190-45-2-1. A promising line, SR25848-C99-1-2-1, selected by the pedigree breeding method, was designated the name of 'Suweon 519' in 2007. This cultivar has about 155 days of growth period from seeding to heading, and is tolerance to lodging, with erect pubescent leaves as well as a long and thick culm. This cultivar has the same number of tillers per hill and higher spikelet numbers per panicle compared to Nokyang. 'Mogwoo' has longer leaves compared with other Tongil-type varieties. This new variety is resistant to grain shattering, leaf blast, bacterial leaf blight, and small brown planthopper. The biomass yield of 'Mogwoo' was 1,956 kg/10a in a regional test over three years. The result shows that 'Mogwoo' is adaptable to central and south-east plain areas of Korea.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.90-96
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• 2010

In this study, the anti-oxidant, anti-tumorigenic, anti-hypertensive, anti-thrombic, anti-diabetic, and anti-inflammatory properties of 18 different species of genus Pleurotus were investigated. In addition, the amino acid, $\beta$-glucan, and polyphenol content were also measured. All species contained more than 20 mg% of polyphenol with the highest contents found in Pleurotus cornucopiae var. citrinopileatus (yellow pleurotus) ($39.13{\pm}0.82\;mg%$). The $\beta$-glucan contents was also the highest in yellow Pleurotus ($37.67{\pm}0.22%$) followed by Won-Hyeong1 (C, $28.75{\pm}0.61%$) and Jang-an PK (A, $27.95{\pm}0.33%$). The yellow Pleurotus exhibited the highest antioxidant activity as assessed by the DPPH scavenging rate with an $IC_{50}$ value of $2.94{\pm}0.44\;mg/mL$. Ethanol extracts from the yellow Pleurotus treated at 1% concentration showed cytotoxic activity up to 36.9% in the human embryonic kidney 293T cell lines. The yellow Pleurotus also showed the highest inhibitory effects on ACE activity ($60.52{\pm}0.2%$). Finally, the yellow Pleurotus exhibited anti-diabetic and anti-inflammatory properties as shown by inhibition of $\alpha$-amyloglucosidase activity ($50.5{\pm}0.8%$) and nitric oxide production ($68.4{\pm}0.3%$). Taken together, our data indicate the yellow pleurotus is a promising functional food ingredients.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3514-3523
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• 2009

Before 1990's, Korea had only few colleges that had film and film related majors. As Korean film industry started its marvelous improvement in both commercial and artistic phase, many colleges were interested in this new academic field. They hurried up to launch this new and profitable major; as a result, Korea now has more than hundred colleges and universities that has film related majors. Each college enumerates numbers of academic courses that may look reasonable; they have almost every course a fine film school should provide such as film theory, production, and performance in film. Lots of film schools offer lots of film courses; and they look alike. One unique thing in film major is its vast sub fields and categories. After you decide to study film, you have to select what specific field in film you want to study. Studying film theory and film production can be as different as majoring physics and physical education. The problem Korean colleges are dealing with is that there are too much film schools, and moreover those colleges have similar curriculums that just look like a department store that sells everything. One suggestion is specializing its curriculum in which the school can take advantages using their special conditions. San Francisco Art Institute is one of United States well known private film schools, but many people remember this school as a specialized film school in experimental film. San Francisco where this school is located has had many liberal and experimental artists as the city has been supporting and offering them an environment they can concentrate their work. Naturally, the school has world famous faculty members in experimental film, and students who want to study and make experimental film come to this school from all over the world because they know this school would be the best to study experimental film. There are many film schools in metro Los Angeles area; since its location near Hollywood, no wonder these schools concentrate on film producing and film production. They take advantage of their geographical location to hire film industry professional and to focus on commercial feature film productions. What we can do now to adjust the curriculum in film and film related major in Korean colleges is to adapt new standards in this changed film industry. One school can emphasize digital production while another school focuses on digital intermediate process. But if one school tries to both fields or all fields of film major just like we have done so far, the school could not take care of all the equipment and the faculty that the fields would need. Korean film schools should devide the field in film major and concentrate what they selected. Selection and concentration can be and should be applied in Korean film schools.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.3
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• pp.274-282
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• 2013

This study was carried out to find out the physicochemical properties of rice grains of 8 varieties having various amylose content. Amylose contents of 8 varieties were ranged from 6.3 to 30.9% and could be classified into 4 groups, such as waxy, low-amylose, nonglutinous, and high-amylose. Protein contents were ranged from 5.8% to 7.5% varied depending on variety, but there was no significant difference in protein contents among groups. The hardness of milled rice grains in low-amylose and non-glutinous was stronger than waxy and low-amylose group. Whiteness of waxy group grains was the highest while non-glutinous group was the lowest. The alkaline digestive values were evenly distributed from 5.2 to 6.9 and highly correlated with amylose content. There was significant difference in pasting properties of rice flours among groups. High-amylose group showed the highest initial pasting temperature and total setback viscosity, and the lowest peaks for trough and breakdown viscosity. Low-amylose group showed the highest breakdown viscosity but the lowest setback viscosity as well as high peak viscosity. Although amylose content was significantly correlated with alkali spreading value in milled rice, initial pasting temperature, and total setback, but it was negatively correlated with toyo-meter value and setback viscosity.

• Reproductive and Developmental Biology
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• v.36 no.1
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• pp.27-32
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• 2012

This study was carried out to investigate artificial insemination (AI) failure status and frozen semen characteristics in Korean proven bulls' number (KPN) semen used for AI of Hanwoo cows in Gangwon East region (Gangneung, Donghae, Taebaek, Samcheok, Sokcho, Yangyang, Goseong). Among semen used for AI, AI failure rate showed lowest at KPN506 (27.6%), whereas highest at KPN593 (77.2%). Correlations of AI failure in between Korean proven bulls semen and cows was 0.2941, which means that AI failure rate of Korean proven bulls semen may have respectable effect on reproduction of Hanwoo cow. In addition, present study was conducted to investigate spermatozoal viability rate, ruptured acrosome rate and active mitochondria in frozen Korean proven bulls semen with flow cytometry. The semen of KPN593 showed significantly ($p$<0.05) higher viability rate in KPN593 (30.49%) than that in KPN637 (37.34%). Furthermore, percentage of ruptured acrosome was lower in KPN637 as 21.37% than in KPN637 (21.37%), but it was not statistically significant. In conclusion, these results indicate that choice of Korean proven bulls semen may correlate positively with conception rate in Hanwoo cow. Therefore, KPN with high AI failure rate might be avoid to increase conception rate and characteristics of frozen semen might be evaluated before its use for AI.

• Reproductive and Developmental Biology
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• v.36 no.1
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• pp.65-70
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• 2012

For reconstituting genetic resource(Korean Native Chicken: KNC) with grem-line chimeric chicken made with cryopreserved biastdermal cells, the experiments were carried out to optimize cryopreservating conditions. Stage X biastdemal cells were collected from KNC embryos and dissociated. Cells were susupended in medium containing cyopretectant and fetal bovine serum(FBS), and distributed into plastic ampules. Cell susupensions were seeded to induce ice formation at $-7^{\circ}C$ to $-35^{\circ}C$ at in the experiments, the effect of modification of dissociation way, concentration of FBS and cell density on the vaibility of frezen-thawed cells were investigated by trypan blue exclusion. Then change the way of cell dissociation from pipetting to short time vortexing, viability of frozen-thawed cell tended to be increaced from 29 % to 52 %. Increase concentraition of FBS in frozen medium from 20 % to 80 % made viability of thawed cell from 28 % to 35 %. The viability of thawed cells were 33.9% frozen at 2 embryos/0.5 ml, and 43.6 % frozen at 20 embryos/0.5 ml. Furthermore, combination of three modifications make big improvement. The viability of frozen-thawed cell was 60 % for combinated method, and 41 % for general method. This result means the advance to practical cryoreservation of blastdermal cell of the KNC(Ogolgye breed).

• Journal of Animal Science and Technology
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• v.53 no.4
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• pp.325-332
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• 2011

This research was conducted to analyze the effects of raising farm on the heritability and breeding values of Hanwoo cows for their carcass traits, including cold carcass weight (CWT), back-fat thickness (BFT), eye-muscle area (EMA) and marbling score (MAR). The carcass data and pedigree data were collected from steers raised on Hanwoo farms in Pyeongchang-gun, Gangwon-do, South Korea. Three analytical models were applied for the estimation of heritabilities and breeding values. The first model (model 1) included slaughter house-year-month combination as fixed effects and age at slaughter was fitted as linear and quadratic covariates. The second model (model 2) was similar to model 1, but raising farm was additionally included as random effect. The third model (model 3) was similar to model 1 but farm effects were additionally included as fixed effect. The comparisons between the model 1 and the models including farm effect (model 2 and model 3) revealed that heritability estimates from model 2 or model 3 were smaller to those from model 1 for all carcass traits. Especially, obvious decrease of heritability was observed in CWT where heritability was 0.23 from model 1, 0.15 from model 2 and 0.18 from model 3. The maximum log likelihood of the model 2 and 3 were higher than those of model 1 for all traits. In model 2 that raising farm was included as a random effect, the ratio of farm variance to the total phenotypic variance were ranged from 4% (EMA) to 18% (CWT). Top 10% and bottom 10% of female cows were selected based on the breeding values from model 1, and the Spearman's rank correlation coefficients among models were estimated for each trait within selected group. The correlation coefficients were ranged from 0.57 to 0.95 in top 10% group and from 0.68 to 0.95 in bottom 10% group. These results show that the discrepancies in the rankings of breeding values can be based on the models applied. In conclusion, the results obtained in this study suggest that the herd effect or farm effect should be included in the analytical model when breeding values are estimated with the purpose of improvement of carcass traits of Hanwoo breeding cows.