• Journal of Korean Society on Water Environment
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• v.33 no.4
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• pp.441-448
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• 2017

Microcystis aeruginosa (M. aeruginosa) is a cyanobacterium species that can form harmful algal blooms in freshwater bodies worldwide. The use of Artemisia asiatica extracts to control M. aeruginosa inhibition will be environmentally friendly and promising. Artemisia asiatica extracts removed successfully upto 88% of M. aeruginosa pH 8 at $25^{\circ}C$ of temperature. These results was indicated that the amount of 2.24 g/L Artemisia asiatica extracts was removed 1g dryweight/L of M. aeruginosa. The kinetic data showed substrate inhibition kinetics and maximum growth rate was obtained when the M. aeruginosa was grown in medium containing 2.5 g/L of initial concentration of Artemisia asiatica extracts. In the various growth control models, Luong model showed the highest correlation coefficient of 0.9916. Therefore, the Luong model was the most suitable control model for the growth control of M. aruginosa using Artemisia asiatica extracts. In conclusion, the growth control of M. aruginosa using Artemisia asiatica extracts can be applied in the field without controlling the temperature and pH of rivers and streams, and it is possible to control the growth of M. aruginosa efficiently in a short time. The natural extract, Artemisia asiatica extracts, can be a promising inhibition due to its high efficiency and low dose requirements.

• Journal of Hydrogen and New Energy
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• v.24 no.2
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• pp.99-106
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• 2013

The variations of performance and metabolites at an early stage were investigated for the successful start-up technology in continuous fermentative hydrogen production. Unsuccessful start-up was observed when the operation mode was changed from batch to continuous mode after the yield was reached to 0.5 mol $H_2$/mol $hexose_{added}$ by batch mode. $H_2$ production continued till 12 hours accompanied by butyrate production, but did not last with propionate production increase. It was suspected that the failure was due to the regrowth of propionic acid bacteria during batch mode which were inhibited by heat-shock but not completely killed. Thus, successful start-up was tried by early switchover from batch to continuous operation; continuous operation was started after the $H_2$ yield was reached to 0.2 mol $H_2$/mol $hexose_{added}$ by batch mode. Although $H_2$ production rate decreased at an early stage, stable $H_2$ yield of 0.8 mol $H_2$/mol $hexose_{added}$ was achieved after 10 days by lowering down propionate production. And it was also concluded that the reason for $H_2$ production decrease at an early stage was due to alcohol production by self detoxification mechanism against VFAs accumulation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.5
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• pp.28-39
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• 2003

This study was carried out to elucidate effective restoration measures for natural forest with recycling native tree un site from November 2001 to October 2002 to obtain a basic information for revegetation measure, eight experimental treatment was done and the length of stump, root-ball size of stump, antisepsis treatment of trunk cut, Planting season and contents of organic matter in soil were effective on regrowth of root-stock. Thirteen tree species including Quercus acutissima among twenty tree species showed outstanding sprout and survival rate(over 90 percent), Planting in November and combinated planting with 5 trees and 9 shrubs of root-stock per 100$m^2$ plot showed a good growth. And 10 percent of organic matter plot showed a good crown coverage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.10 no.3
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• pp.158-163
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• 1990

This experiment was to study the effect of pure mineral nitrogen fertilizing on seasonal distribution of dry matter yield and the advisable mineral nitrogen amounts on grassland. The results were as follows: 1. With longer regrowth periods the absolute dry matter yields and the nitrogen-efficiences due to nitrogen fertilizing increased substantially, whereas the quality declined at the relatively lesser cutting frequencies. 2. The first cut at 3-cut regimes, the first and fourth cut at 4-cut regimes, and the second and last cut at 5-and 6-cut regimes showed the highest nitrogen-efficiency, respectively. 3. By the sigmaformed process of production curve the most efficient mineral N-dressing rate per ha and cut was calculated: 42-56kg N on the 3-cut areas, 39-55kg N on the 4-cut areas, 38-47kg N on the 5-cut areas and 35-48kg N/ha/cut on the &cut areas. 4. In dependence on site and kind of calculation the economical borders were reached with the following dressings of mineral N/ha/cut: 90-100kg on the 3-cut areas, 70-100kg on the 4-cut areas and 50- 90kg on the 5-and 6-cut areas.

• Journal of Korean Neurosurgical Society
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• v.65 no.6
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• pp.841-845
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• 2022

Objective : Chiari III malformations are extremely rare hindbrain malformations that are associated with a high early mortality rate, or severe neurologic deficits in the survivors. The treatment is early operative closure and cerebrospinal fluid diversion (CSF) shunting. Methods : We operated on 15 patients by repair and excision between July 2014 till June 2020 and retrospective data collection was done. Only one patient doesn't need ventriculoperitoneal (VP) shunt and the other 14 patients need a VP shunt. We described stepwise dissection and untethering of the cerebellum from the bony edge to regrowth and herniation of cerebellum again into this potential space and simple dural closure or repair with graft was done. Results : We started with VP in eight patients (53%) and the other seven patients (46.7%) started with excision and then six patients need VP shunt later on because four patients developed CSF leak and two patients developed increased high intracranial tension. Only four patients (26.7%) needed a blood transfusion. Conclusion : There are variations in the outcome and not all cases of Chiari malformation III will die and severe developmental delay is not a must. Proper management and repair carry a good prognosis.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.41-48
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• 1992

This experiment was carrid out to determine the effect of cutting height and nitrogen level on dead stubble, tiller and branch new shoot dry matter yield and total dry matter of sorghum-sudangrass hybrid{Sorghum bicolor (L.) Moench}.The main treatment was four cutting height(5cm, IOcm, 15cm, 20cm), and the sub treatment was three nitrogen level(l50kg, 250kg, 350kglha).The experiment was performed at the Collage of Natural Science of Kon-Kuk University at Chungju in 1988. 1. Plant length tends to increase in the high cutting height and high N level. Especially, the difference of plant height was significant in warm season. 2. The number of dead stubble after cutting was significantly(P

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.271-277
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• 2010

The purpose of this study is to investigate the seasonal variation of picoplankton community in Lake Juam depending on the change of physico-chemical factors such as rainfall, water depth, DO and pH. The concentration of chlorophyll-a was most high as 18.03 mg/$m^3$ in July when the rainfall and water temperature were highest. The concentration was gradually decreased in October, April and that of January was decreased most low as 1.86 mg/$m^3$. The highest concentration of the Chl-a was shown at 2 and 5 m of water depth than surface, and the concentration was gradually decreased when the water depth becomes deep. Overall, microplankton was the highest rate as 33.9~54.2%, nanoplankton was 24.3~30.5% and picoplankton was 21.6~41.2%. Picoplankton was included as considerable concentration in the water of Juam lake. Therefore it is necessary to remove thoroughly the picoplankton in the water treatment processes such coagulation·sedimentation and sand filtration. The protoplasm released from destruction of picoplankton by chlorine has high possibility to cause regrowth of bacteria and pathogenic microorganism in the distribution system by playing the role of the assimilable organic carbon.

• Journal of Bio-Environment Control
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• v.26 no.4
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• pp.291-296
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• 2017

This study was conducted to evaluate the influence of early defoliation on photosynthesis and carbohydrate reserves when the source leaves of 'Fuji'/M9 apple (Malus domestica Borkh.) trees were removed during the growing period. Bud regrowth rates of 80%, 50% defoliation and non-defoliation treatments were significantly different 82.7%, 45.9% and 2.1% respectively at 30 days after treatment. In all treatments, sucrose and starch concentrations in remaining leaves decreased non-significantly during the 14-day period. No significant changes were observed for total soluble carbohydrates in non-defoliation and 50% defoliation. However, in 80% defoliated treatments, concentrations of sorbitol and total soluble carbohydrates in remaining leaves declined steadily during the 14-day period. It is thought that high sink strength increases the requirements of carbohydrate from remaining leaves more than non-defoliated. The concentrations of starch in the roots tend to decrease non-significantly as percentage of defoliation increased. Photosynthesis of remaining leaves was monitored during the 14-day period after partial defoliation treatments. Net photosynthetic rates (Pn) and stomatal conductance were significantly enhanced in the 80% defoliation. The observed photosynthetic enhancement following partial defoliation may have been due to the enhancement of osmotic potential in leaves. These results were estimated that increasing of photosynthetic rate in the partial defoliation is due to the sink carbohydrate requirements for the current year's secondary growth of buds.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.483-488
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• 1997

This experiment was conducted to determine cutting time on the yield and nutritive value of brittle culm rice. Plant height and number of tiller were significantly different between variety and cutting time, and regrowth plant height and rate of regrowth tiller were tall and high at the early cutting. Early cutting increased crude protein, fat and NFE(Nitrogen free extract) content in the harvested foliage but crude fiber and ash content were decreased in the first cutting. Those of second cutting also showed reverse tendency. Fresh and dry matter yield were highest on heading date cutting, and those of KL501 were higher than those of Seomjinbyeo. TDN(Total digestible nutrients) content was higher with earlier cutting for initiated cutting, but that of second cutting was reversed. KL501 showed higher TDN content than Seomjinbyeo did at the any cutting time. TDN yield of heading date cutting was higher than that of the other cutting time.

• Korean Journal of Plant Tissue Culture
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• v.26 no.4
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• pp.229-233
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• 1999

The possibility for long-term preservation of Larix leptolepis embryogenic tissue was tested in this study. Higher relative increase of the tissue fresh weight was observed when embryogenic tissue was pretreated for 24 hrs in a medium containing 0.4 M sorbitol or 20% polyethyleneglycol with cooling rate of -0.33$^{\circ}C$/min. The fast cooling rate of -0.5$^{\circ}C$ and -1.$0^{\circ}C$/min appeared to be less effective in regrowth of tissues from cryopreservation. No DNA variants have been observed by PCR analysis among the embryogenic tissues recovered after 1-, 7-, and 28-day-cryopreservation. The post-thaw embryogenic tissue gave rise to mature somatic embryos which developed into plants.