• Journal of Nutrition and Health
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• v.22 no.4
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• pp.266-274
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• 1989

The current study was undertaken to determine the effects of the ratios of dietary fat to carbohydrate and energy restriction on insulin sensitivity in the growing rats. Male rats weighting 80-90g were fed experimental diets for two weeks. Rats were killed and epiddymal adipose tissue were removed and sliced. Explants of adipose tissues were incubated for 2 hours in KRB(Krebs-Ringer bicarbonate) buffer containing various concentrations of human insulin and [U-14C]glucose. Insulin sensitivity was determined as glucose conversion to total lipids (lipogenesis) during 2 hr incubation. Exp't I : Effects of Ratios of Fat to Carbohydrate on Insulin Sensitivity. Eighteen male rats were fed 3 diets for 2 weeks. Diet 1 was low fat-high carbohydrate (4% soybean oil and 66.5% cornstarch) ; diet 2, medium fat-medium sarbohydrate(12% soybean oil and 58.5% cornstarch) ; diet 3, high fat-low carbohydrate (20% soybean oil and 50.5% cornstarch). Insulin sensitivity was higher in the order of LF-HC, MF-HC and HF-LC diet groups (p<0.05), i.e, lipogenesis was higher at all insuline concentration in the explants from rats fed LF-HC diet. However, thers was no significant difference in body weight gain and epididymal adipose tissue weight among treatments. Exp't II ; Effects of Energy Restriction on Insulin Sensitivity. Twelve rats were grouped into ad libitum feeding and restricted feeding(70% of ad libitum). The experimental diet was medium fat-medium carbohydrat diet as used in the Exp't I. Restricted feeding group tended to show higher insulin sensitivity compared to ad libitum group. However, there was no statistical difference between two groups. As expected, body weight gain and epididymal adipose tissue were higher in the ad libitum group. In summary, the resutls of the current study showed that the epididymal adipose tissue taken from the rats fed low fat-high carbohydrate diet showed higher insulin sensitivity compared to those fed high fat-low carbohydrate, and that resticted feeding tended to elevate insulin sensitivity in these tissues.

• FLOWER RESEARCH JOURNAL
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• v.19 no.1
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• pp.49-54
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• 2011

The influences of MS medium strength, sucrose concentration, and light condition on bulblet formation and growth were studied in leaf tissue culture of Muscari armenicum 'Early Giant'. Bulblet formation from leaf segments were the most effective on MS medium supplemented with $0.01mg{\cdot}L^{-1}$ NAA, $0.2m{\cdot}L^{-1}$ kinetin, $30g{\cdot}L^{-1}$ sucrose, and $8g{\cdot}L^{-1}$ gelrite under darkness for 2 weeks followed by 16 hr photoperiod with a photosynthetic photon flux density of $50mol{\cdot}m^{-2}{\cdot}s^{-1}$. However the compactness of bulblets formed in vitro was promoted in the MS medium with $60gL^{-1}$ sucrose. Acclimatized plants flowered during the second year of the growing period without any phenotypic variations and formed average 1.5 bulblets per mother bulb.

• Ocean and Polar Research
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• v.43 no.2
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• pp.53-63
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• 2021

Changes in a marine environment have a broad socioeconomic implication on fisheries and their relevant industries so that there has been a growing demand for the medium-range (months to years) prediction of the marine environment Using a medium-range ocean prediction model (Ocean Mid-range prediction System, OMIDAS) for the northwest Pacific, this study attempted to assess seasonal difference in the mid-range predictability of the sea surface temperature (SST), focusing on the Korea seas characterized as a complex marine system. A three-month re-forecast experiment was conducted for each of the four seasons in 2016 starting from January, forced with Climate Forecast System version 2 (CFSv2) forecast data. The assessment using relative root-mean-square-error was taken for the last month SST of each experiment. Compared to the CFSv2, the OMIDAS revealed a better prediction skill for the Korea seas SST, particularly in the Yellow sea mainly due to a more realistic representation of the topography and current systems. Seasonally, the OMIDAS showed better predictability in the warm seasons (spring and summer) than in the cold seasons (fall and winter), suggesting seasonal dependency in predictability of the Korea seas. In addition, the mid-range predictability for the Korea seas significantly varies depending on regions: the predictability was higher in the East Sea than in the Yellow Sea. The improvement in the seasonal predictability for the Korea seas by OMIDAS highlights the importance of a regional ocean modeling system for a medium-range marine prediction.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.10a
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• pp.16-16
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• 2019

The Cassava (Manihot esculenta Crantz) is a perennial woody shrub cultivated mainly in the tropics for its starchy tuberous roots. It belongs to the family Euphorbiaceae which also includes rubber (Hevea brasiliensis) and castor bean (Ricinus communis). Among tropical crops, rice, sugarcane, maize and cassava are the most important sources of calories for human consumption. Problems in the propagation of cassava are virus diseases and low rates of seed germination. Thus, a study was undertaken to develop an efficient in vitro mass propagation protocol of Manihot esculenta Crantz. Young and actively growing stem segments were excised from adult plants of cassava. Samples were cut into a 3~4 cm nodal segments with single node after sterilization, and cultivated in the different medium supplemented with various plant growth regulators for 4 weeks. For shoot multiplication, single-node stem segments, approximately 1 cm in length, were taken from in vitro derived shoots and subcultured. After 4~6 weeks, the shoot generation rate was 55.6%, the shoot number and its length were 1.0/explant and 2.3 cm in the most favorable medium composition. Our experiments confirmed that in vitro growth and multiplication of plantlets could depend on its reaction to the different medium composition, and this micropropagation techniques could be a useful system for healthy and vigorous plant production.

• Current Research on Agriculture and Life Sciences
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• v.12
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• pp.69-82
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• 1994

This study was conducted to investigate the physiological characteristics and to isolate plasmid DNA of R. japonicum strains. The results obtained were as follows; Strains S117, S118, 005, 011 and DY-1 were slow-growers and showed alkaline reaction, whereas strains S110, S111, S114, S116, S120 and 010 were fast-growers and produced acid reaction in YEM broth. All the fast- and slow-growing R. japonicum showed gram negative and formed mucous white colony on agar plate. After 7 days, the colonies of the fast-growers were between 2.0 and 4.0mm in diameter, whereas those of slow-growers were approximately between 0.5 and 1.5mm. The fast-growers were uniformly sensitive to the pH of 4.5 and tolerant of the pH of 9.5, whereas the reverse was found for the slow-growers. All the fast-growers were able to grow in the presence of 2% NaCl however the slow-growers were not grown. All the microorganisms grew rapidly in simple mineral salt medium containing as the sole source of carbon. Starch was rarely utilized. All the fast-growers utilized sucrose. The slow-growing R. japonicum strains examined usually contained 1 to 3 plasmid DNA ranging between 15Kb and 250 Kb, whereas the fast-growing R. japonicum strains contained 1 to 3 plasmid DNA ranging from 20 Kb to 250Kb.

• Journal of Environmental Science International
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• v.25 no.5
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• pp.625-633
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• 2016

This study was conducted to investigate the influence of hydrophilic polymer (HP) mixture ratio (Control, 1.0%, 2.5%, 5.0%, and 10.0%) on growth of eggplant (Solanum melongena) for lower maintenance urban agriculture via green roofs. Although it was not statistically significant (p > 0.05), substrate temperature was decreased as hydrophilic polymer mixture ratio were increased. High substrate water content (95%) was found consistently in growing media under elevated hydrophilic polymer mixture ratio at over 5% during the entire growing period. Substrate electronic conductivity was increased as hydrophilic polymer mixture ratio were increased. Growth index was decreased as hydrophilic polymer mixture ratio was increased. It was reduced about 1/3 and 1/5 compared to that of Control in HP5.0 and HP10.0 treatment plants, respectively. Number of leaves, leaf length, and leaf width were decreased in following order: Control> HP1.0> HP2.5> HP5.0> HP10.0 treatments. There numbers were significantly lower in HP5.0 and HP10.0 treatment plants. Dry weight of shoot and root were decreased as hydrophilic polymer mixture ratio was increased. They were reduced by 1/4 compared to those of Control treatment plants. In addition, visual value was decreased as hydrophilic polymer mixture ratio was increased. Plants grown in HP1.0, HP2.5, and HP5.0 treatments all survived. However, plants grown in the HP10.0 treatment had the lowest survival rate (56%) after 3 months of growing. These results indicate that the advantage of adding hydrophilic polymer to green roof growing media may greater during dry periods. However, the proper mixture proportion of hydrophilic polymer should be determined according to different characteristics of growing media and plant species.

• Journal of Plant Biotechnology
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• v.7 no.4
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• pp.241-246
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• 2005

Factors affecting regeneration of different Rubus varieties (blackberry, raspberry and their hybrid) were examined and a reliable regeneration system was established. Media for stock plant maintenance were tested; different explants and media were investigated to find the best circumstances for the regeneration. The effect of the commonly used antibiotics was studied to determine the most suitable one for selection of the transformants. We found that both MS and LS media supplemented by $20\;gL^{-1}$ sucrose are suitable for the stock plant maintenance. The optimal hormone content for the stock plants is $0.125\;mgL^{-1}$ 6-benzylaminopurine (BAP) with $0.01\;mgL^{-1}$ indole-3- butyric acid (IBA). The highest regeneration rate was observed on medium containing MS salts with B5 vitamins complemented with glucose, sucrose, maltose, $10\;gL^{-1}$ each, supplemented with benzylaminopurine riboside (BAR) ($2\;mgL^{-1}$) and indole-3-acetic acid (IAA) ($0.1\;mgL^{-1}$). The regenerated shoots appeared directly from the cut edges, without callus phase. Hygromycin and geneticin proved to be good selection agents for the Rubus explants, but due to their severe effect on the tissues we propose to use marker-free constructions for the transformation.

• Korean Journal of Poultry Science
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• v.24 no.3
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• pp.153-160
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• 1997

This study was carried out to estimate the heritability and genetic correlation for body weight, shank length and shank width at various wk of age in growing Korean pheasant. All the measurements were done from one day to 20 wk of age with 4 wk interval. The heritability estimates for body weight were in the range of 0.54~0.59 for male and of 0.49~0.81 for female from 4 to 20 wk of age. The heritability estimates of male and female were in the range of 0.38~0. 82 and 0.41~0.67 for shank length, and of 0.48~0.88 and 0.49~0.71 for shank width, respectively. Genetic and phenotypic correlation coefficients between the measurements at different ages in each trait of body weight, shank length and shank width were medium to high positive values. Because the estimates of heritabilities and genetic correlations were high, the genetic gain for body weight is expected by either a direct selection or an early selection based on the record of early growing stage.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.252-257
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• 1995

Growth rates of the low temperature growing isolates, Pseudomonas fluorescens M45 and MC07, reached maximum stationary phase within 50 hrs at the low temperature, 4$^{\circ}C$. But an ordinary biocontrol agent P. putida Pf3 did not reach logarithmic growth phase until 80 hrs. The culture filtrates of M45 and MC07 significantly inhibited the mycelial growths of Pythium ultimum, Rhizoctonia solani and Phytophthora capsici. Detached cotyledons of cucumber grown on Murashige and Skoog agar medium were much enhanced in their growth, compared to those without the filtrates. Population densities of M45 and MC07 in the rhizosphere at 14$^{\circ}C$ were more stable than at 27$^{\circ}C$. When M45 and MC07 were treated into soil, the population density of MC07 continuously increased up to 9 days after treatment, and sustained the initial inoculum density up to 60 days. Cucumber damping-offs caused by P. ultimum and R. solani were significantly reduced by applying M45 as seed-inoculant and by soil treatment with MC07. The combined treatment of M45 and MC07 provided greater effect in reducing the disease incidence than that obtained by single treatments.

• The Plant Pathology Journal
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• v.20 no.4
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• pp.289-292
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• 2004

The population of Ralstonia solanacearum (Rs) in soil is very important as a primary inoculum source of bacterial wilt in tobacco fields. To investigate the population of Rs, physical properties and chemical components during the tobacco growing season, soil samples were taken from the fifteen fields which were located in the flue-cured tobacco growing area, Ansung, Kyunggi province and Wonju, Kangwon province. Two fields of the fifteen were bacterial wilt free. Six fields had less than 10% plants being diseased and seven over 10%. The Rs population level determined by using SMSA medium generally showed an up-and-down pattern being low in May, high in Jun and July and low in August. The soil population in May and June showed a positive correlation with the incidence of bacterial wilt (r=0.571$^*$, r=0.688$^{**}$), but P$_2O_5$, content of soil was negatively correlated with the disease incidence (r=-0.539$^*$). These results suggest that Rs population in soil examined in May or in June, and the P$_2O_5$ content in soil should be key factors to determine the bacterial wilt potential of tobacco fields.