• Korean Journal of Environmental Biology
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• v.27 no.2
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• pp.176-182
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• 2009

We surveyed the total 30 sites in Gilgol, Nae Sorak for the patterns of the natural regeneration of the korean fir in connection with the characteristic of the stand. The natural regeneration in a forestrical meaning is not found in natural forest but mainly in the anthropogenically already disturbed area. It may be inferred from this fact that the anthropogenic disturbance can give more better condition for a natural regeneration. The regeneration phase in the natural forest is not so distinctive as the artificial forest, and shows itself transiently. And it may be also said that a shift in generation is only a part of the change of the stand phase. The concept of the natural regeneration will lose its meaning, in so far as the patch dynamic determines the phase of the stand, and the main tree species are shade-tolerant abies.

• Journal of Forest and Environmental Science
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• v.38 no.2
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• pp.90-101
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• 2022

The study aims to assess composition, diversity and population indices of natural regeneration of woody species in Jebel El Gerrie forest reserve, Blue Nile State, Sudan. We conducted field work between December 2018 and January 2019. We used random sampling to collect vegetation data in the forest where we made a total of 90 circular sample plots (radius 17.84 m) and distributed them proportionally to the area of each of the four density-based vegetation classes of the forest i.e. high density (C1), medium density (C2), low density (C3) and crop land (C4). In each sample plot we identified all regenerating tree species and counted their regeneration frequencies. We calculated ecological metrics of regeneration frequency, density, abundance, richness, evenness, diversity and importance value index (IVI) and drew abundance rank curve. Results revealed that out of fifteen mature tree species present, natural regeneration of 8 species, which belong to 6 families, was observed. The relatively most frequently naturally regenerating and abundant species were Anogeissus leiocarpa and Combretum hartmannianum. Richness, evenness and diversity of regenerating species were 1.33, 0.82 and 1.7, respectively. One-way ANOVA (α=0.05) of mean regeneration densities disclosed that there were significant differences (F_3,86=16.77, p=0.000) between C2 & C3 (p=0.000) and C2 & C4 (p=0.000). While regeneration of seven tree species were absent, two, two and four species were of good, poor and fair regeneration status, respectively. A comparison of mean density of natural regeneration with that of parent trees reflects a poor regeneration status of the forest. The study provides empirical results on the regeneration status of species and signifies the need for management interventions for species conservation and restoration, maintenance of biodiversity and sustainable production.

• Journal of Microbiology and Biotechnology
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• v.1 no.4
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• pp.246-250
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• 1991

Conditions for the production and regeneration in Lactobacillus bulgaricus protoplasts were investigated. Protoplasts of L bulgaricus strains were obtained by treatment with mutanolysin and lysozyme together in a protoplast forming buffer containing 0.02 M N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) (pH 7.0) and 0.5 M sucrose. High protoplast yield was obtained from cells cultured in the de Man, Rogosa and Sharpe(MRS) medium at the middle to late logarithmic growth phase. Regeneration was efficiently accomplished with a complex medium containing 1% sucrose, 20 mM $MgCl_2$, 5% gelatin, and 0.5% bovine serum albumin. The frequency of regeneration of protoplasts was 10~20% after 5 days of incubation at $30^{\circ}C$.

• Journal of Plant Biology
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• v.39 no.2
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• pp.93-98
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• 1996

In order to enhance the system of potato transformation and further regeneration, potato was transformed using the Agrobacterium tumefaciens harboring $\beta$-glucuronidase (GUS) gene. We found that a series fo modified medium ttained 100% shoot regeneration within 5 weeks after the preincubated explants on stage I medium were infected with Agrobacterium. Callus appeared at the cut edges of stem segments on stage II medium, mainly at the basal parts. Some explants started to form shoots after two to three weeks on stage III medium containing kanamycin (50 mg/L). When transferred to MS medium containing 200 mg/L kanamycin, 81% of the transformed shoots formed roots at the cut edge of the plantlets. In contrast, untrasformed shoots never rooted and became yellowish after few weeks under the same conditions. Southern and northern analysis indicated in vitro shoot regeneration on the callus derived from the potato explants, which were incubated with Agrobacteria. The regeneration cycle was shortened after the transformatin and finally the transformation efficiency was highly enhanced.

• Journal of Ecology and Environment
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• v.29 no.1
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• pp.17-22
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• 2006

Since the demands not only for value-added timber but the environmental functions of forests had been increased, native tree species has been, and is rapidly being replaced by foreign tree species in many parts of the world. However, the studies on population structure and regeneration characteristics of native tree species were not conducted enough. Regeneration of Kalopanax septemlobus growing among other hardwoods in natural forests is very difficult because of its low seed viability and germination rate. The study examined the distribution of mature trees of K. septemlobus and their regeneration pattern at the 1.12 ha study plot in natural deciduous broad-leaved forest of Mt. Jeombong. The density and mean DBH of K. septemlobus was 97 trees per ha and 32 cm, respectively. The spatial distribution of K. septemlobus showed a random pattern (aggregation index is 0.935) in the 1.12 ha study plot. The age of 90 trees among 99 sample trees of K. septemlobus ranged from 90 to 110 years and represented a single cohort, thus suggesting that K. septemlobus in advance regeneration has regenerated as a result of disturbances such as canopy opening.

• Plant Resources
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• v.8 no.3
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• pp.275-280
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• 2005

Tissue culture systems to optimize regeneration plant species of Ocimum spp were evaluated as a method to micropropagate individual plants and to better study their biology in vitro. Ocimum species were also evaluated for the production of natural plant products during and following the regeneration process. The primary goal of this project was to enhance the regeneration efficiency of basil. Several factors were examined using different Ocimum species and commercial varieties. The effect of cytokinin combination, activated charcoal, gelling agents, and different carbon sources were investigated. Anthocyanin callus spots were produced only in four varieties among six tested. 'Sweet Dani' showed the best results on anthocyanin accumulation, while 'African beauty', 'Tree basil' and 'Methylcinnamate' produced only a few spots. Shoot regeneration was only achieved from 'Sweet Dani' explants. As the activated charcoal concentration increased, callus formation rate decreased respectively compare to the controls for all varieties. There was a decrease in callus growth with increasing concentration of agar and phytagel.

• Korean Journal of Microbiology
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• v.30 no.6
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• pp.514-518
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• 1992

The present study has been perromed to investigate the optimal conditions for protoplast formation and regeneration of oleandomycin-producing Streptomyces antibioticus (S. antibioticus) KCTC 1081. Mycelia were grown in YME medium containing 0.2% (w/v) glycine and converted into the protoplast by incubating at 35.deg.C for 60 minutes in protoplast buffer (P buffer) containing 4 mg/ml lysozyme. The reversion of protoplasts to the normal filamentous state was examined by the growth on various synthetic agar media. A high reversion rate was obtained by incubating the protoplasts on a hypertonic agar medium containing 20 mM $Mg^{++}$, 5 mM $Ca^{++}$ and 0.3 M sucrose at 28.deg.C for 5 days. From these experiments, we established the improved regeneration medium and a protocol which supports higher and more consistent levels of regeneration of S. antibioticus protoplasts. The regenerant showed an increased antimicrobial activity compared with that of the initial strain.n.n.

• Microbiology and Biotechnology Letters
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• v.22 no.2
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• pp.143-151
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• 1994

In the course of the study on strain inprovement by protoplast fusion, Lactobacillus acidophilus 88 protoplasts production and regeneration conditions were investigated. This strain produced a bacteriocin that revealed strong inhibitory activity against various indicator strains, especially L. helveticus CNRZ 1096. Protoplasts of L. acidophilus 88 strains were very efficiently obtained by treatment with 125 $\mu $g/ml lysozyme in a protoplast forming buffer containing 20 mM N-2 hydroxy-ethtl-piperazine-N'-2-ethane-sulfonic acid(HEPES, pH 7.0) and 1M sucrose at 37$\circ $C for 30 min. Hovever, treatment with mutanolysin was not effective for the production of L. acidophilus 88 protoplasts under the same conditions. High protoplast yield was obtained form the cells at the middle to late logarithmic growth phase in the de Man, Rogosa and Sharpe(MRS) medium. Regeneration was efficiently accomplished with the MRS medium containing 10% sucrose.

• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.2
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• pp.161-173
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• 2002

Recently, absorbent biofilters, which are inexpensive and easy to manacle, have been supplied to the rural areas, but have limitations in removing the nutrients effectively. Accordingly, as an alternative plan. natural zeolites were arranged in front or at the rear of the absorbent biofilters, and their removal efficiency for nitrogen and, ultimately, their applicability to the on-site wastewater treatment system were studied. Furthermore, the same experiments were carried out on artificial zeolites, made from coal ashes at National Honam Agricultural Experiment Station, to compare natural zeolites with artificial ones. Treated wastewater through the Absorbent Biofilter showed 22.6% nitrogen removal efficiency, while 64.6% was attained when natural Zeolites were placed in front of the absorbent biofilters (Zeolite-Aerobic process). As an addition, phosphorus was also efficiently removed. On the other hand, Aerobic-Zeolite process, which arranged natural zeolites at the rear of the biofilters, did not have significantly higher nitrogen removal as compared to the treatment using only the absorbent biofilters. Furthermore, upon regeneration of the natural zeolite, the ion exchange rate was fecund to increase over 10% as compared to before regeneration. Our results show that natural zeolites, applied to the on-site wastewater treatment system through the Zeolite-Aerobic process, not only increase the removal efficiency of nutrients, but, by choosing the appropriate regeneration time, can also be cast-effective. Artificial zeolites, on the other hand, though more efficient in removing nutrients, cannot be regenerated and, therefore, are not cost-effective.

• Journal of Korean Society of societal Security
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• v.1 no.1
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• pp.45-51
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• 2008

The purpose of this study is to suggest some effective ways to implement the regeneration projects for the zones vulnerable to natural disasters which have been delayed due to shortage of the financial resources, and thereby complete the disaster prevention projects as early as possible and thus secure the financial resources for the projects continuously. For this purpose, the researcher reviewed the statutory grounds and designation procedures or the zones vulnerable to natural disasters, and thereupon, examined and analyzed the regeneration projects being implemented in Gyeonggi-do in view of contents by zone, history of damages, annual investment plans and financial resources for investments. In addition, the researcher examined the criteria for reserve of the disaster management fund and its uses and investigated the fund sources and expenditures and thereby, addressed the problems of the statutory reserve and suggested their solutions. All in all, the researcher suggested that the disaster management fund should be invested in regeneration projects for the zones vulnerable to natural disasters in order to remove the disaster risks earlier and that the uses of the fund should be adequately deregulated with a reserve fund ceiling system to secure the financial resources for the disaster prevention projects continuously.