• Korean Journal of Ecology and Environment
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• v.38 no.4 s.114
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• pp.503-509
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• 2005

The growth characteristic of a predominant planktonic blooming species, Mallomonas elongata in a small shallow eutrophic pond was investigated In the field (from October 2004 to September 2005) and laboratory, Dense blooming (max. 17,600 cells $mL^{-1}$) of this silica-scaled chrysophytes was observed for a short time period in early spring (water temperature 12-$18^{\circ}C$ and pH 8.4-9.5), The growth characteristics of M. elongata isolated from this pond was investigated at various temperatures and pH under batch culture. The unialgal culture of M. elongata showed maximum growth rate (${\mu}max$) at $15^{\circ}C$ similar to the natural conditions. However, the optimal pH of the isolated batch culture was lower than the pond water pH at which M. elongata appeared in large population density.

• Korean Journal of Plant Tissue Culture
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• v.27 no.3
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• pp.197-202
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• 2000

The effect of cultural media and growth regulators on multiple plant regeneration from leaf explants of Heloniopsis orientalis (Thunb.) Tanaka was evaluated. The highest percentage of shoot and root formation were 20 and 30% on MS medium treated at 3.0 mg $l^{-1}$ of zeatin, respectively. Also 67 and 33% of high shoot formation appeared on 1/2 MS and 5 culture medium treated at zeatin 1.0 and 3.0 mg $l^{-1}$ respectively. With MS treated at 0.5 mg $l^{-1}$ of 2,4-D 1/2 MS and B5 culture media treated at each 1.0 and 3.0 mg $l^{-1}$ of zeatin the highest ratios of plant produced were 100, 280 and 310 % respectively relative to the other treatments. Generally, there was highest possibility for multiple propagation of Heloniopsis orientalis (Thunb.) C. Tanaka with B5 culture media supplemented 3.0 mg $l^{-1}$ of zeatin.

• Journal of Periodontal and Implant Science
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• v.24 no.3
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• pp.581-596
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• 1994

This in vitro study was undertaken to obtain optimal tetracycline concentration that aids proliferation and spreading of human periodontal ligament cells, for clinical application in root surfaces of periodontally diseased teeth. Periodontal ligament cells used in this study were obtained from explants of periodontal ligament of 1st premolar teeth which were extracted for the purpose of orthodontic treatment. The cells were cultured in Dulbecco's Modified Eagle Medium(DMEM) supplemented with 100 U/ml penicillin, $100\;{\mu}g/ml$ streptomycin and 10% FBS at $37^{\circ}C$, 100% humidity, 5% $CO_2-95%$ air. Cells were used between the third to 4th passage. After root planing of periodontally extracted teeth, the root slabs were cut with carborundum disk. In the cell proliferation experiment, experimental groups were root planing only group, immersed groups in 25, 50, 75, 100, 150mg/ml aqueous solution of Tetracycline HCl followed by a vigorous rinse in PBS. Human PDL cells at concentration of $1{\times}10^5\;cells/ml$ were seeded in each culture well which contained root slabs and incubated for 6 hours. Then, all of the root slabs were moved into new 24 culture well and incubated 24, 48 and 72 hours. The cell counting was done by inverted phase contrast microscope after trypsinization. The following results were obtained. The cell number was increased in order root planing only group, 25, 150, 50, 75, 100mg/ml of Tetracycline HCl treated group in 24, 48 and 72 hours. The maximal cell number was obtained when the root slabs were immersed in solution with 100mg/ml of Tetracycline HCl. There were statistically significant between the root planing only group and 75, 100 mg/ml of Tetracycline HCl treated group in 24 hours, between the root planing only group and 100mg/ml of Tetracycline HCl treated group in 48 hours, between the root planing only group and 50, 75, 100mg/ml of Tetracycline HCl treated group, between 25 and 100mg/ml of Tetracycline HCl treated group in 72 hours(p<0.05). In the cell spreading experiment, after 30 minutes of incubated, in the root planing only group, the cells were generally round in shape. The cell surface was mostly covered with blebs. The cells started to attach to root surface by cytoplasmic extension in 50, 100mg/ml of Tetracycline HCl treated groups, more numerous cells attached to root surface than root planing only group. Many orifices of dentinal tubule were exposed, cells showed radially spreaded cytoplasm and unspreaded central region of the cell was covered with blebs. After 6 hours of incubation, in the root planing only group, cells showed radially spreaded cytoplasm and were attached flat appearance. In 50, 100mg/ml of Tetracycline HCl treated groups, cellular margin was concaved and cytoplasm showed elongated appearance with polarity. After 24 hours of incubation, in the root planing group, cells showed characteristic polarity. In 50, 100mg/ml of Tetracycline HCl treated groups, cells showed more elongated and spindle - like appearance.

• Korean journal of applied entomology
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• v.53 no.2
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• pp.141-147
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• 2014

Pinewood nematode (PWN: Bursaphelenchus xylophilus) is known to kill pine tree species that are indigenous to countries where the pest was inadvertently imported, but some cultures from the extraction of dead pines do not damage trees. Experiments were conducted to examine the effect of pre-inoculation of these low-pathogenic pinewood nematode on resistance of pine trees against the pest species. The pre-inoculated pine saplings showed induced resistance which lasted for a year, and repeated inoculation of these low-pathogenic nematodes enhanced tree resistance. All nematode samples extracted from dying or dead pines that had been killed not more than three months before the extraction were pathogenic, and most of those extracted from pines that had been killed 2-3 years before were low-pathogenic. When inoculated in pine saplings, number of low-pathogenic nematodes settled, as studied two days after inoculation, was not different from that of pathogenic ones. However, as studied after 30 days of inoculation, rate of reproduction in low-pathogenic nematodes was far lower than that of pathogenic nematodes. The rate of reproduction of several nematode isolates growing on fungal mat media of Botrytis cinerea varied, but three of four low-pathogenic isolates showed same level of reproduction rates as pathogenic ones.

• Journal of Plant Biotechnology
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• v.46 no.2
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• pp.106-113
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• 2019

The objective of this study was to carry out treatment of various plant hormones in order to determine morphological and genetic variation degree of tissue-cultured strawberry. The cultivar used in this experiment was 'Goha' and 'Seolhyang', the plant hormones used for experiment were benzyladenine (BA), N-(2-Chloro-4 pyridyl)-N'-phenylurea (CPPU) and thidiazuron (TDZ), and the concentrations were 0.5, 1.0, 2.0, $4.0mg{\cdot}L^{-1}$ with each hormone. The BA treatment of the proliferation efficiency of tissue-cultured strawberry 'Goha' and 'Seolhyang' was the highest. When processing BA, CPPU and TDZ, morphological variation and genetic variation happened in strawberry 'Goha' and 'Seolhyang', especially, the variations appeared highly in CPPU treatment. The genetic variation in 'Goha' appeared at the concentration more than BA $0.5mg{\cdot}L^{-1}$ as 1.1%, appeared at the concentration of CPPU $0.5mg{\cdot}L^{-1}$ as 15.3%, and at the concentration of TDZ $2.0mg{\cdot}L^{-1}$ as 1.2%. The genetic variation in 'Seolhyang' appeared at the concentration of BA $4.0mg{\cdot}L^{-1}$ as 2.3%, and at the concentration of CPPU $0.5mg{\cdot}L^{-1}$ as 14.3%. Therefore, CPPU should not be treated during strawberry tissue culture, and BA and TDZ should be treated at low concentration.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.05a
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• pp.11-11
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• 2010

패모(貝母)는 땅속의 뿌리줄기에 있는 2매의 비늘조각(인편(鱗片))이 마치 조개처럼 합쳐 있어 패모라 불리우며, 백합과로 숙근성 다년생 초본의 절패모(浙貝母; Fritillaria thungergii) 및 동속식물의 비늘줄기를 기원으로 하며, 중국의 강소 절강 안휘 등지에서 대량으로 재배되고 있다. 패모의 줄기는 15~40cm정도로 곧게 자라며, 꽃은 4~5월에 피며, 윗부분의 엽액에 1개씩 밑을 향하여 달린다. 종자는 결실률이 매우 낮아 이용을 할 수 없어 번식은 대부분 비늘줄기의 인편이나 자구를 이용한다. 약용부위는 인경(鱗莖)(비늘줄기)이 사용되는데, 인경(鱗莖)에는 알칼로이드물질인 verticine, fritillin, peimisine, peimine 등의 주요 성분을 함유하여 약리작용으로는 중추신경마비, 혈압강하 및 진해작용이 있다. 한방에서는 진해, 거담, 배농, 폐렴, 기관지염 등으로 이용하는 중요한 약초 중의 하나이나, 값싼 중국산 패모의 수입으로 우리나라에서는 재배가 붕괴되어 현재는 재배면적이 거의 없는 자원고갈 약초로 재배면적 확보가 시급한 실정에 있어 이를 되살리기 위한 노력이 절실한 실정이다. 따라서 패모 자구 증식을 위하여 온도와 $GA_3$, 상토의 조건에 따른 시험을 수행한 결과 패모 자구의 증식 효과는 저장온도 온도가 낮을수록 자구의 증식이 많아 $5^{\circ}C$에서 주당 5.5개로 구수의 증식효과가 높았으며, 상토는 모래와 밭흙에서 각각 3.1개, 2.5개로 많았으나, $GA_3$과 온탕처리에 있어서는 차이가 없었다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.1
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• pp.102-107
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• 1984

This study was undertaken to know the possibility of in vitro propagation of Stevia through axillary bud culture and the results indicated that: (1) Addition of NAA (0.01-0.05 mg/l) alone on Murashige-Skoog basal medium promoted shoot differentiation and growth rate. And also additional of kinetin of 0.5-1.0 mg/1 alone showed the same trend as that of NAA: (2) Addition of both NAA (0.01-0.05 mg/l) and kinetin (0.5-1.0mg/l) to MS medium promoted better shoot formation. (3) Shoot differentiation and growth were better on the full salt strength of MS medium (1X MS) than that of half strength ( $\frac{1}{2}$MS), while their effects were reversed for root differentiation

• The Journal of the Convergence on Culture Technology
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• v.4 no.4
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• pp.331-335
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• 2018

Zantedeschia spp. calla is very popular as a cut flower. It is very important to establish a micro propagation system through plant tissue culture with the problem that colored calla with various colors are low in natural reproduction rate and vulnerable to high temperature. In this study, we conducted the experiment by adding taurine to improve the growth of calla plant. When 20 mg/L of taurine was added with plant growth effect, 54.0 % of the cases of multiple shoots and 17.2 times of fresh weight were the most effective. Taurine 20 mg/L treatment showed 16.0 % and 39.2 %, respectively, than the untreated control. Taurine may contribute to mass propagation of elite breeding lines as well as an improvement of farm income by positively influencing the overall growth of calla plants, thereby positively affecting the establishment of the micro propagation system of calla shoot tips.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.2
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• pp.221-227
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• 2021

Recently, interests in mask-type skin care devices using light-emitting diodes have been increasing and optical stimuli at certain wavelengths have been known to have various therapeutic effects, such as skin whitening, acne treatment, elasticity and wrinkle improvement by controlling the exposure to wavelengths of light and irradiation time. In particular, light sources of different wavelengths are applied in masks for the purpose of suppressing skin aging, inducing cell proliferation, and alleviating skin inflammation. In this paper, we developed a light-emitting diode control system that is actively used in skin regeneration masks using a microcontroller. Optical stimuli with different manners were applied to skin fibroblast cells in a single or complex wavelengths, and then confirmed how they are effective in the cell differentiation. In addition, we found a specific wavelength that has a positive effect on cell proliferation rates, and confirm the effectiveness of cell proliferation by image processing based quantitative analysis.

• Radiation Oncology Journal
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• v.7 no.2
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• pp.171-183
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• 1989

A general effect for cell proliferation has been incorporated into Roesch's survival equation (Accumulation Model). From this an isoeffect formula for the low dose-rate regimen is obtained. The prediction for total doses equivalent to 60Gy delivered at the constant dose-rate over 7 days agrees well with the dose-time data of Paterson and of Green, when the parameter ratio A/B (${\approx}{\alpha{\mu}}/2{\beta}\;where\;{\mu}$ is the repair rate) is chosen to be 0.7Gy/h. When a constant proliferation rate and known facts of division delay are assumed, an isoeffect relation between low dose-rate treatment and acute dose-rate treatment can be derived. This formula in the regimens where proliferation is negligible predicts exactly the data of Ellis that 8 fractions of 5 Gy/day for 7 days are equivalent to continuously applied 60Gy over 7days, provided the A/B ratio is 0.7 Gy/h and the $\alpha/\beta$ ratio is 4Gy. Overall agreement between the clinical data and the predictions made by the formula at the above parameter values suggests that the biologcal end points used as the tolerance level in the studies by Paterson, Green, and Ellis all agree and they are not entirely the early effects as generally assumed. The absence of dose-rate effects observed in the mouse KHT sarcoma can better be explained in terms of a large value for the A/B ratio. Similarly, the same total dose used independently of the dose-rate to treat head and neck tumors by Pierquin can be justified.