• Journal of Embryo Transfer
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• v.19 no.2
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• pp.185-189
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• 2004

The purpose of this study was to determine the possibility of in vitro maturation of tiger oocytes. Immature oocytes were recovered from a pair of ovaries. A total of 78 oocytes was collected, of which forty three were classified as good oocytes with compact cumulus cells and uniform cytoplasm. Forty three COCs were in vitro matured at $39^{\circ}C$, 5% CO2 in air atmosphere for 48 h in a IVM medium (TCM-199 supplement with 10% FBS, 0.6 mM cysteine, 0.2 mM pyruvic acid and 10 IU/mL HMG). Experiment I: the morphologic evaluation was conducted by measuring the diameter of oocytes with or without ZP, the thickness of ZP and the diameter of cytoplasm by microeyepiece at the same magnification (${\times}$100). Experiment II: the evaluation of meiotic development was conducted of the nuclear development stage of tiger oocytes. The results were summarized as follows: 1. The diameter of tiger oocytes $(176.5\pm6.1{\mu}m)$ with ZP was significantly (p<0.05) bigger than that of bovine oocytes $(150.7\pm4.9{\mu}m).$ The ZP thickness of tiger oocytes $(20.4\pm2.9{\mu}m)$ was significantly (p<0.05) bigger than that of bovine oocytes $(12.0\pm2.6{\mu}m;$ p<0.05). However, there was no significant difference in the diameter of cytoplasm (without ZP) between tiger $(122.1\pm9.7{\mu}m)$ and bovine oocytes $(118.7\pm7.5{\mu}m).$ 2. The rates of meiotic development of tiger oocytes were achieved GV (12.5 %) and MII (50.0%), respectively. These results indicated that tiger oocytes could be developed to MII in in vitro culture system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.13-21
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• 1985

This experiment was carried out to study the effect of the autumnal cutting times on the regrowth, the accumulated carbohydrate and dry matter yield of Italian ryegrass The results were summarized as follows: 1. In dry matter yield, the plot of earlier cutting was shown the highest yield (p<0.05), and that of the last-cutting was shown lower yield of dry matter than that the none-cutting plot. 2. TSC (Total Water Soluble Carbohydrate) content slightly decreased after the first cutting and gradually increased according to the regrowth, and then decreased again to the second cutting time. And also the TSC content levels of stubble, stem and leaf at one week before falling to sub-zero temperature were all the highest in the eariler cutting plot (p<0.01), and there was significant correlation between the TSC content level and the second harvested dry matter yield (p<0.05). 3. CGR (Crop Growth Rate) was decreased below $8^{\circ}C$. RLGR (Relative Leaf area Growth Rate) and NAR (Net Assimilation Rate) were both high during 30 days after regrowth, and low after regrowth in all plots. LAI (Leaf Area Index) rapidly increased during 50 days after cutting, and then slowly increased in all the plots, and maximum LAI was 3.4-5.8. Also dry matter yield increased in the plots having a high LAI to 70 days after cutting. 4. It was recognized that there were significant correlation between TSC, LAI, CGR, NAR, LWR (Leaf Weight Ratio) and the second harvested dry matter yield during the low temperature periods, and the degree of contribution to dry matter yield was in order of LWR>LAI>TSC>NAR>CGR.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.265-272
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• 2002

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum $\times$ L. pratensis and intergeneric hybrids of Lolium $\times$ Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12$^{\circ}C$ of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

• Korean Journal of Soil Science and Fertilizer
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• v.10 no.3
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• pp.135-151
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• 1977

The present paper summerizes the studies on clay mineralogical characteristics of Korean soil, relationship between potassium and clay minerals, potassium release pattern of clay minerals and utilization of clay minerals for soil conditioner and fertilizers, which have been carried out in this laboratory. 1. The red yellow podzolic soil is mostly abundant in the upland of Korea and mainly consists of halloysite and weathered intermediates of mica such as illite and vermiculite. 2. With regard to soil parent material, kaolin mineral occurs abundant in soils derived from granite and granite gneiss. Mica is dominant in basaltic soil. The main clay mineral of the soil, originated from the Tertiary, is found montmorillonite and the volcanic soil of Jeju Island has plenty of allophane as its main clay mineral. 3. It is confirmed that the soil fertility depends on the composition of clay minerals. The red yellow podzolic soil, containing lot of kaolin, shows low productivity while the montmorillonite soil has higher productivity. 4. The release rate of solid phase potassium (micas and fixed potassium) follows the 1st order reaction equation in the equilibrium solution of $IN-NH_4OAc$. The potassium release constant is positively correlated with the mica content of the clay but negatively correlated with the content of $14.5{\AA}$ minerals. On the other hand, the potassium release constant has very high correlation with the ratio(Kex/Kt) of exchangeable potassium(Kex) to total potassium(Kt). 5. It is also found that Kex/Kt has rather high correlation with the content of mica and $14.5{\AA}$ minerals existed in the clay as well as the mica content of the soil.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.4
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• pp.322-331
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• 2016

Oil budget calculator identifies the removal pathways of spilled oil by both natural and response methods, and estimates the remaining oil required response activities. A oil budget calculator was newly developed as a response tool for Deepwater Horizon oil spill incident in Gulf of Mexico in 2010 to inform clean up decisions for Incident Comment System, which was also successfully utilized to media and general public promotion of oil spill response activities. This study analyzed the theoretical background of the oil budget calculator and explored its future application to Korea. The oil budge calculation of four catastrophic marine pollution incidents indicates that 3~8% of spilled oil was removed mechanically by skimmers, 1~5% by in-situ burning, 4.8~16% by chemical dispersion due to dispersant operation, and 37~56% by weathering processes such as evaporation, dissolution, and natural dispersion. The results show that in-situ burning and chemical dispersion effectively remove spilled oil more than the mechanical removal by skimming, and natural weathering processes are also very effective to remove spilled oil. To apply the oil budget calculator in Korea, its parameters need to be optimized in response to the seasonal characteristics of marine environment, the characteristics of spilled oil and response technologies. A new algorithm also needs to be developed to estimate the oil budget due to shoreline cleanup activities. An oil budget calculator optimized in Korea can play a critical role in informing decisions for oil spill response activities and communicating spill prevention and response activities with the media and general public.

• Clinical and Experimental Pediatrics
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• v.46 no.4
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• pp.340-344
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• 2003

Purpose : We evaluated allele frequencies and distribution of surfactant protein A2(SP-A2) in Korean neonates in order to estimate the prevalence of RDS, to find out new SP-A alleles, and to establish new steroid therapy. Methods : Genomic DNA was extracted from 71 neonates and served as a template in PCR for genotype analysis. SP-A gene-specific amplications and gene-specific allele determinations were performed using PCR-cRFLP methods. Results : The distribution for the alleles of the SP-A2 gene in the study population was 1A, $1A^0$, $1A^1$, $1A^2$, $1A^3$, $1A^5$, $1A^6$, $1A^7$, $1A^8$, $1A^9$, $1A^{11}$, $1A^{12}$. The specific frequencies for the alleles of the SP-A2 gene in the study population were : 1A=11.3%, $1A^0=38%$, $1A^1=12.7%$, $1A^2=9.2%$, $1A^5=15.5%$, $1A^7=2.9%$, $1A^8=4.9%$, $1A^9=2.2%$, others=3.3%. Conclusion : The frequency of $1A^0$ was higher than the other SP-A2 alleles in Korean neonates. This finding suggests that the prevalence of RDS in Korea may be low compared with other countries. However, this finding also suggests that Korean neonates have a high risk of infection.

• The Korean Journal of Food And Nutrition
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• v.22 no.3
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• pp.321-331
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• 2009

In this study, Salvia miltiorrhiza Bunge(Danshen) powder was extracted with ethanol, and its antimicrobial activity was investigated. The ethanol extract of the Danshen had antimicrobial activity against Bacillus subtilis, Escherichia coli, and Staphylococcus aureus. The inhibition zones of the Danshen extract(3 mg/disc) against B. subtilis, E. coli and S. aureus were 13, 12 and 8.5 mm, respectively. To test the food preservation effect of Danshen and determine the optimal ratio of the Danshen extract in a formulation, Sulgidduk samples were prepared with substitutions of 0, 0.25, 0.5, 0.75 and 1% Danshen extract, and then their quality characteristics were investigated over 4 days of storage. According to the results, total cell counts showed a decreasing trend with an increasing amount of added Danshen extract. Moisture contents were not significantly different among the Sulgidduk samples. As the content of Danshen extract increased, the L-values of samples decreased and the a- and b- values increased. For the textural characteristics, the hardness, gumminess, and chewiness of the Sulgidduk samples decreased as the amount of Danshen extract increased; however, they increased with the progression of storage time. In the sensory evaluation, the control group had significantly higher scores for color, flavor and after-taste as compared to the Danshen extract-added groups. With increasing Danshen extract contents, flavor and overall acceptability decreased, while Danshen flavor, bitterness and off-flavor increased. Chewiness was not significantly different among the samples. In conclusion, the results indicate that substituting 0.5% Danshen extract in Sulgidduk is optimal for quality and provides a product with reasonably high overall acceptability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.4
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• pp.327-332
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• 2010

This study was conducted to overcome the deliciousness by sex reversal in hemp plants. When female plants grown under long day length condition were transferred to short day length condition in 3th and 6th leaf stage, a few male flowers were formed and the gap of flowering days between sex reversed male and normal female flowers were around 10 days and 3 days, respectively. Although the flowering amounts were small, this short gaps of flowering days were enough for artificial pollination. When female plants grown under long day length condition were transferred to short day length condition just after treatment of silver nitrate in the vegetative stage, a great amount of male flower was formed and the gap of flowering days between sex reversed male and normal female flowers were only 1 to 3 days. The increased sex reversed male flowers and induced short gap of flowering days were adequate for natural wind pollination. When female seeds were cultivated, seed yield was 141 kg/10a, while it was 96 kg/10a when normal seeds cultivated.

• Journal of Environmental Science International
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• v.20 no.11
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• pp.1417-1423
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• 2011

For evaluating the effect of various organic fertilizer ratios on the Spiraea${\times}$bumalda 'Gold Mound' growth, a container green wall system experiment was conducted in a greenhouse at Konkuk university. The experimental planting grounds were prepared with different organic fertilizer ratios ($A_1L_0$, $A_8L_1$, $A_4L_1$ $A_2L_1$ and $A_1L_1$) and with drought tolerance and an ornamental value Spiraea${\times}$bumalda 'Gold Mound' was planted. The change in soil moisture contents, plant height, number of branches, number of dead leafs, number of leaf, number of shoots, length of node, length of leaf, width of leaf, root-collar caliper, chlorophyll contents and survival rate were investigated from April to Jun 2010. 1. The result of soil moisture contents was analyzed with weight unit in the container green wall system during the dry summer season. The soil moisture contents were significantly enhanced in the container green wall system in increasing order as the amount of fertilizer level increased $A_1L_1$ > $A_2L_1$ > $A_4L_1$ > $A_8L_1$ > $A_1L_0$. 2. Compared to the control treatment (amended soil with 100% + organic fertilizer 0%) application, the highest plant growth was observed in the treatment of $A_2L_1$(amended soil with 67% + organic fertilizer 13%) application. However, the differences between the organic fertilizer ratio treatments of $A_1L_1$, $A_4L_1$, $A_8L_1$, and the $A_1L_0$ organic fertilizer application were mostly not significant. 3. The survival rate increased with the increasing application of organic fertilizer, but in the control treatment (amended soil with 100% + organic fertilizer 0%) application all the plants died. Experimental results from the presented study clearly demonstrated that the organic fertilizer improved the survival rate more than the Spiraea${\times}$bumalda 'Gold Mound' growth at different levels of organic fertilizers. This strain can be utilized as a plant growth application in living wall systems during the dry summer season. Therefore, Spiraea${\times}$bumalda 'Gold Mound' is expected to be a highly valuable shrub for the green wall system if it should be considered in integration with stormwater retention or as a soil conditioner for increasing soil water contents in planting ground.

• Journal of Climate Change Research
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• v.2 no.1
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• pp.55-68
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• 2011

The Intergovernmental Panel on Climate Change(IPCC) has identified the causes of climate change and come up with measures to address it at the global level. Its key component of the work involves developing and assessing future climate change scenarios. The IPCC Expert Meeting in September 2007 identified a new greenhouse gas concentration scenario "Representative Concentration Pathway(RCP)" and established the framework and development schedules for Climate Modeling (CM), Integrated Assessment Modeling(IAM), Impact Adaptation Vulnerability(IAV) community for the fifth IPCC Assessment Reports while 130 researchers and users took part in. The CM community at the IPCC Expert Meeting in September 2008, agreed on a new set of coordinated climate model experiments, the phase five of the Coupled Model Intercomparison Project(CMIP5), which consists of more than 30 standardized experiment protocols for the shortterm and long-term time scales, in order to enhance understanding on climate change for the IPCC AR5 and to develop climate change scenarios and to address major issues raised at the IPCC AR4. Since early 2009, fourteen countries including the Korea have been carrying out CMIP5-related projects. Withe increasing interest on climate change, in 2009 the COdinated Regional Downscaling EXperiment(CORDEX) has been launched to generate regional and local level information on climate change. The National Institute of Meteorological Research(NIMR) under the Korea Meteorological Administration (KMA) has contributed to the IPCC AR4 by developing climate change scenarios based on IPCC SRES using ECHO-G and embarked on crafting national scenarios for climate change as well as RCP-based global ones by engaging in international projects such as CMIP5 and CORDEX. NIMR/KMA will make a contribution to drawing the IPCC AR5 and will develop national climate change scenarios reflecting geographical factors, local climate characteristics and user needs and provide them to national IAV and IAM communites to assess future regional climate impacts and take action.