• Journal of Plant Biotechnology
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• v.2 no.3
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• pp.123-128
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• 2000

To enhance in vitro plantlet regeneration efficiency of soybean through embryogenesis, the culture conditions such as material part and size of immature seed, 2,4-D, pH and solidifying agents for somatic embryogenesis were investigated. Somatic embryogenesis was induced from the immature embryo, immature cotyledon and embryonic axis explants of the immature seed on MS medium supplemented with 2.0 mg/L 2,4-D. The highest rate (up to 22.9%) of somatic embryogenesis was obtained from the immature cotyledon, following embryonic axis and the immature embryo. The rate varied with the developmental stages of seed. The maximum rate (25.4%) of embryogenesis was obtained from 3-4 mm length of the seed (after 25 days of flowering). The optimum concentration of 2,4-D for embryogenesis was 10 mg/L. The optimum pH was at 5.8 and solidifying agent for medium was better with 0.4% gelrite than with agar. For rapid multiplication of shoot tips from the germinating somatic embryos, they were cultured on MS medium containing 2 mg/L indole-3-butyyic acid (IBA) and 1 mg/L 6-benzyladenine (BA). After then somatic embryos with one and three cotyledons were transferred to the growth regulator free medium. The medium exhibited the higher rate (ca. 50%) of development than the multiplication medium.

• Journal of Environmental Science International
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• v.7 no.6
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• pp.833-843
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• 1998

It is noted that the red tides and the oxygen-deficient water mass are extensively developed in Masan Bay during summer. The nutrients mass balance was calculated in Masan Bay, using the three-dimensional numerical hydrodynamic model and the material cycle model. The material cycle model was calibrated with the data obtained on the field of the study area in June 1993. The nutrients mass balance calculated by the combination of the residual currents and material cycle model results showed nutrients of surface and middle levels to be transported from the inner part to the outer part of Masan Bay, and nutrients of bottom level to be transported from outer part to inner part of Masan Bay. The uptake rate of DIN in the box A1(surface level of inner part) was found to be 337. 5mg/$m^3$ㆍday, the largest value in all 9 boxes and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1, and the regeneration rate of DIN was found to be 78.2mg/$m^3$ㆍday in the box A3(bottom level of inner part), and that of DIP was found to be 18.6mg/$m^3$ㆍday in box A1. The regenerations of DIN and DIP in the water column of the entire Bay were found to be 7.66ton/day and 760kg/day, respectively. And the releases of DIN and DIP from the sediments of the entire Bay were found to be 2.86ton/day and 634kg/day, respectively. The regeneration rate was 2.5 times as high as the release rate in DIN, and 1.2 times in DIP. The results of mass balance calculation showed not only the nutrients released from the sediments but the nutrients regenerated in water column to be important in the control and management of water quality in Masan Bay.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.585-590
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• 2011

The purpose of this research is to suggest economic feasibility of cultivating Acer Mono by using profitability analysis to forest owners. To achieve this research objective, forest owner household survey with intensive cultivating has been conducted about a sap production on its age of tree. And input costs and sap production costs are calculated with silvicultural system from plant to regeneration cutting. Total income is the sum of its sap sales and thinning and regeneration cutting. The method of profitability analysis was used on the NPV(Net Present Value) and IRR(internal rate of return). Finally, when 3% discount rate is applied, NPV is about 59,436 thousand won and IRR value is 9.22% at this point. This result, therefore, proves that cultivating Acer Mono is economical feasibility to forest owners.

• Journal of Plant Biotechnology
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• v.48 no.1
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• pp.54-61
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• 2021

This work describe an efficient method for the shoot induction and plant regeneration of seedling-derived apical bud explants of Tilia mandshurica Rupr. & Maxim. The highest rate of shoot induction (82.2%) was obtained when apical bud explants from juvenile seedlings (5 months old) were cultured on Murashige and Skoog (MS) medium containing 1.0 mg/L 6-benzylaminopurine (BAP). However, apical bud explants obtained from mature trees (12 years old) did not produce any shoots, even with BAP supplementation. Among the three cytokinins tested for shoot multiplication (BAP, zeatin, and kinetin), BAP was the most effective; the highest number of shoots per explant (2.1) was observed on MS medium supplemented with 1.0 mg/L BAP. In contrast, the longest average shoot length (3.0 cm) was observed after growth on MS medium with 2.0 mg/L zeatin. No multiplication occurred when apical bud explants were cultured with kinetin-supplemented media. During rooting of in vitro-elongated shoots, the highest rooting rate (100%) was observed in half-strength MS medium supplemented with 0.5 ~ 1.0 mg/L indole-3-butyric acid (IBA) or 3.0 mg/L 1-naphthaleneacetic acid (NAA). During the acclimatization process, plantlets that were rooted on the IBA (0.5 mg/L)-supplemented medium had the highest survival rate (100%) and maximum root length (18.5 cm). These findings suggest that a low concentration (0.5 mg/L) of IBA is appropriate for the rooting and acclimatization of T. mandshurica. Plants were successfully transferred to the greenhouse with a 100% survival rate. This protocol will be useful for the large-scale propagation of Tilia species.

• Korean Journal of Plant Tissue Culture
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• v.22 no.5
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• pp.267-271
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• 1995

To improve regeneration efficiency of Brassica campestris ssp. pekinensis (chinese cabbage) in vitro, the effect of ehtylene inhibitors [AgNO$_3$ and silver thiosulfate (STS)] and optimal age of explantse were investigated. On the effect of ethylene inhibitors either 100 $\mu$M of AgNO$_3$ or 5 $\mu$M of STS enhanced shoot regeneration from cotyledons when it was added in basal shoot induction media(MS salts, B5 vitamine, sucrose 2%, BA 2.0mg/L, NAA 1.0mg/L). But at higher concentrations, AgNO$_3$ induced abnormal shoots, and STS greatly reduced regeneration frequency. On the other hand, the maximum regeneration rate was obtained from the cotyledons taken from 3-day old seedlings. However there was no distinctive effect among the containers used for cultivation. The most optimal condition of root induction was a minimal Murashige and Skoog media containing 0.1 mg/L NAA. In order to induce bolting and flowering from in vitro regenerated chinese cabbage, the plant were healed at 4$^{\circ}C$ for weeks in a cold chamber. When they were planted in pots, the plane produced phenotipically normal flowers and seeds. The overall results suggest that ethylene inhibitors promote regeneration of shoot from cotyledons of chinese cabbage without alleviating fertility.

• Journal of Aquaculture
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• v.13 no.3
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• pp.253-258
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• 2000

Monthly samplings were made at Yongho-dong, Pusan, on the south eastern coast of Korea from May 1998 to April 1999 to investigate population growth and regeneration pattern of C. okanurae. The growth of erect branches was dependent mainly on the habitat water temperature. Maximum length of an erect branch was 13.4 cm in July and the minimum was 5.1 cm in March; during the corresponding months maximum and minimum weights of the alga were 2.2 and 0.7 g, respectively. During this investigation, gametangia did not occur. Regeneration of excised ramuli was dependent on irradiance. Regeneration rate was the highest under 50 ${\mu}$molm$^{-2}$s$^{-1}$ at 2$0^{\circ}C$. Under the conditions of different combinations of temperature (18, 22, 25, 28 and 1$^{\circ}C$) and irradiance (10, 20, 40, 60 and 100 ${\mu}$molm$^{-2}s$ $^{-1}$) regimes, regeneration of excised erect branch was highly affected by temperature and irradiance. The highest regeneration occurred at 25 $^{\circ}C$ and 20 ${\mu}$molm$^{-2}s$$^{-1}$, whereas the highest growth in length (4.5${\pm}$1.0 cm) and fresh weight (1.2${\pm}$0.7 g) was attained after 15 days of culture.

• Journal of Periodontal and Implant Science
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• v.31 no.4
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• pp.737-747
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• 2001

Regeneration of Periodontium with PRP does not only improve regeneration rate and density of bone but have a possibility to estimate faster healing process for soft tissue. And also, synthetic bone and xenogenic bone graft are effective on regeneration of periodontium. The purpose of this study is to evaluate the effectiveness of synthetic bone ($Biogran^{(R)}$) and xenogenic bone ($BBP^{(R)}$) grafts with the PRP technique on regeneration of periodontium. 52 Generally healthy Pt. who had pocket depth 5mm at any of 6 surfaces of the teeth were in the study at Dept. of Perio. in Dankook Dental Hospital. Open Flap was treated for 18 infra-bony pockets as control group, $Biogran^{(R)}$ with PRP was inserted for 25 infrabony pockets as first test group, and $BBP^{(R)}$ with PRP was inserted for 22 infrabony pockets as 2nd test group. Then evaluation was made after 3 and 6 months 1. 6 months after surgery, each difference of average probing pocket depth was $2.61{\pm}0.23$ for control, $3.40{\pm}0.30$ for 1st test, and $3.45{\pm}0.37$ for 2nd test group. 2. 6 months after surgery, each difference of clinical probing attachment level was $1.39{\pm}0.12$ for control, $2.88{\pm}0,24$ for 1st, and $2.86{\pm}0,27$ for 2nd test group. 3. 6 months after surgery, each difference of Maximal probing attachment level was $1.11{\pm}0.16$ for control, $3.28{\pm}0.30$ for 1st, and $3.27{\pm}0.35$ for 2nd test group. 4. There were significant differences for clinical change of each three group which were between average probing pocket depth and clinical attachment level of 3,6 months and minimal and maximal attachment level after 6 months 5. There were significant differences for average probing pocket depth which were only at control group and 2nd test group between 1 and 6months. For clinical attachment level and minimal and maximal proving attachment level, there was a significant difference after 6month of surgery. 6. There was no significant difference between two test groups for average probing depth, clinical attachment level, and minima1 and maximal probing attachment level. As the result, PRP with bone graft is very effective for regeneration of periodontium and there is no difference between xenogenic bone and synthetic bone.

• The Korean Journal of Mycology
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• v.18 no.3
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• pp.115-126
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• 1990

To establish basic techniques for protoplast fusion of Coriolus versicolor several factors affecting protoplast formation and regeneration were investigated. Protoplast isolation was at maximum with 2.5-day cultured mycelia of C. versicolor treated with the combination of two enzymes, Novozym 234 (10 mg/ml) and cellulase Onozuka R-10 (15 mg/ml), for 3-4.5 hours at $30^{\circ}C.$ As an osmotic stabilizer for stabilizing the protoplast, 0.6 M sucrose was the best for formation and regeneration of the protoplast from the mycelia of the fungus and the regeneration frequency was 3.48%. Protoplast fusion was made by a modified method of Peberdy using PEG (M.W. 4,000). The fusion frequency between two mutants of C. versicolor was 1.86% and the fusion products showed differences in growth rate and colony morphology.

• Journal of the Korean Association of Geographic Information Studies
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• v.24 no.4
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• pp.148-163
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• 2021

The diversification of the New Deal urban regeneration projects, that started in 2017 in accordance with the "Special Act on Urban Regeneration Activation and Support", generated the increased demand for the accuracy of data-driven diagnosis and project type forecast. Thus, this research was conducted to develop an application model able to identify the most appropriate New Deal project type for "eup", "myeon" and "dong" across the country. Data for application model development were collected through Statistical geographic information service(SGIS) and the 'Urban Regeneration Comprehensive Information Open System' of the Urban Regeneration Information System, and data for the analysis model was constructed through data pre-processing. Four models were derived and simulations were performed through polynomial regression analysis and multinomial logistic regression analysis for the application of the appropriate New Deal project type. I verified the applicability and validity of the four models by the comparative analysis of spatial distribution of the previously selected New Deal projects by targeting the sites located in Seoul by each model and the result showed that the DI-54 model had the highest concordance rate.

• Journal of Korean Society of Forest Science
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• v.85 no.3
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• pp.524-531
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• 1996

The objective of this study was to determine the important factors affecting the early natural regeneration of Pinus densiflora S. et Z. Seed germination, survival and height growth of the pine seedlings were examined at four experimental plots of P. densiflora forests including forest roadside. Plots I and III were thinned in 1992, plot II was treated with hexazinone in 1993 after seed tree method was applied in 1982 and 1989. Seedlings emerged after thinning and the rate of their emergence depended on forest floor conditions. Seedling survival was related with light conditions, herbaceous vegetation, and degrees of rainfall. More seedlings emerged in forest hauling roads than within the forest because soil scarification due to logging provided better conditions for seed germination and seedling growth. Seed supply was enough, but germination rate was very low in the forest compared with that in the greenhouse because micro-environments such as organic layer and herbaceous plant acted as limiting factors. Weed control was needed for 4 to 5 years until seedlings grew upto about 50cm in height which was similar to that of herbaceous plants. But 10-40% coverage of herbaceous vegetation was needed to protect small seedlings from heavy rain. Forest works such as thinning and logging, over 40% of light were important factors to help the pine regeneration. However, over 70% coverage of herbaceous vegetation, and heavy rain inhibited rather survival and growth of pine seedlings.