• Title/Summary/Keyword: regeneration frequency

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A study of the effects of electric current on the mineralzation of the cultured calvaria bone cells (전기적 자극이 배양 두개관 골세포의 석회화에 미치는 영향에 관한 연구)

  • Park, Joon-Bong;Hur, In-Sik;Lee, Hye-Ja;Choi, Young-Chul
    • Journal of Periodontal and Implant Science
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    • v.27 no.4
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    • pp.949-961
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    • 1997
  • To date, various clinical procedures have been used to restore periodontal apparatus destroyed by periodontal disease. And then, many experimental approaches have been proceeded to develop treatment methods to promote periodontal regeneration. Mechanical, chemical treatments to enhance the attachment of periodontal tissue cells as changing the physical properties of root surfaces, bone graft procedure, and treatments for guided tissue regeneration have been used for periodontal regeneration. However, recent studies have revealed that biologic factors such as growth factors promote biologic mechanism associated with periodontal regeneration. This study was done to enucleate how ELF stimulus affect the periodontal regeneration. We can have following conclusions from this experimental results. The influence of low frequency(ELF) electric stimulus (30Hz at $lO{\mu}A$) known to promote bone formation in vivo, was evaluated for its ability to affect bone cell function in vitro. After 12 hour exposure of ELF stimulus at most appropriate densities ($5{\times}10^4\;cells/cm^2$) to increase osteoblastic cells normally, rat calvarial cells were incubated for 60 hours were used in this study. We have found ELF stimulus suppress calvarial cell proliferation and the ability of protein synthesis, enhance the alkaline phosphatase activity significantly.

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Direct Plant Regeneration and Bulblet Formation from Apical Meristems Culture in Allium wakegi Araki (쪽파(Allium wakegi Araki)의 정단분열 조직배양으로부터 식물체 분화와 인경형성)

  • 송원섭
    • Korean Journal of Plant Resources
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    • v.17 no.1
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    • pp.1-6
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    • 2004
  • Apical meristems tissue were cultured on LS medium with different zeatin and NAA concentrations to compare their potential to regenerate shoots, roots and bulblet formation. Shoot regeneration from apical meristem was effective on LS medium added with zeatin 0.1, 0.5, 1.0 mg/L alone treatment or zeatin 0.5 mg/L and NAA 1.0 mg/L combination treatment. A high frequency of root regeneration was obtained on LS medium supplemented with zeatin 0.5 mg/ and NAA 1.0 combination treatment. Linsmaier and Skoog(LS) medium with NAA 3.0 mg/L and zeatin 1.0 mg/L combination treatment gave the best results for normal bulblet formation#KW=Allium wakegi ; plant regeneration ; bulblet formation

High Frequency Adventitious Shoot Formation and Plant Regeneration in Leaf Explant Cultures of Ixeris sonchifolia Hance, a Newly Proposed Model Plant for Organogenesis

  • Min Sung-Ran;Kim Young-Hoe;Jeong Won-Joong;Han Su-Kyung;In Don-Su;Liu Jang R.
    • Journal of Plant Biotechnology
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    • v.5 no.4
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    • pp.221-224
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    • 2003
  • Leaf explants of Ixeris sonchifolia produced adventitious shoots at a frequency of 100% when cultured on MS medium supplemented with combinations of various concentrations of 6-benzyladenine (BA) (0.44, 4.44, or 8.87 ${\mu}M$) and 0.54 ${\mu}M$ NAA, or MS medium supplemented with 22.19 ${\mu}M$ BA and 2.69 ${\mu}M\;\alpha$-naphthaleneacetic acid (NAA) after four weeks of culture. Each explants (approximately $3{\times}6mm$) produced greater than 70 shoots at a combination of 0.44 ${\mu}M$ BA and 0.54 ${\mu}M$ NAA. Leaf explants produced shoots at a frequency of greater than 80% even at as low as 0.13 ${\mu}M$ BA as the sole growth regulator. Upon transfer to one-third strength MS with 0.54 ${\mu}M$ NAA, excised adventitious shoots were rooted at a frequency of 100%. Regenerated plantlets were transplanted to potting soil and grown to maturity in a greenhouse. The competence of I. sonchifolia for plant regeneration via organogenesis appears to be greater than the competence of tobacco, currently the best model plant for organogenesis.

Multi-Signal Regeneration Effect of Quadrature Digital Radio-Frequency Memory (직교방식 디지털 고주파기억장치의 다중신호 재생성 효과)

  • Lim, Joong-Soo
    • Journal of Convergence for Information Technology
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    • v.9 no.8
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    • pp.134-139
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    • 2019
  • This paper describes the effect of multiple signal regeneration in quadrature digital radio frequency memory(DRFM). Single channel DRFM have good reproducibility after storing a single signal. However, when reproduced after storing multiple signals, the spurious signal is large. The quadrature DRFM consists of I and Q channels, which can greatly reduce the spurious signal. The amplitude of the spurious signal depends on the number of bits of data stored in the DRFM. In this paper, we have obtained the number of bits of signal regeneration according to the application of radio frequency memory by obtaining the size of the spurious signal according to the number of bits of the stored data of the DRFM for multiple signals. As a result of this study, 4 bits quadrature DRFM can achieve a spurious output of less than -20dB, which is used for 4 signals. Those are expected to greatly contribute to the signal analysis of electronic warfare equipment and the development of jamming device.

A System Development of the Protoplast Fusion of Streptomyces coelicolor (Streptomyces coelicolor의 Protoplast Fusion 방법개발)

  • Kim, Jong-Su;Lee, Se-Yong
    • Korean Journal of Microbiology
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    • v.22 no.1
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    • pp.35-40
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    • 1984
  • Attempts were made to optimise protoplast formation and regeneration methods to improve the protoplast fusion frequencies of Streptomyces coelicolor. The yields of protoplast formation and regeneration were varied with different growth phase of the culture. Maximum yields were obtained when cells were taken from the late logarithmic phase. Protoplast formation reached almost its maximum with lysozyme treatment at a concentration of 2mg/ml without any other lytic enzyme. A high frequency of protoplast regeneration was accomplished by overlay method: the method gave 14% recovery of regenerated protoplast versus 1.8% recovery for monolay method. A recombinant frequency of 1.8X10^-2 was obtained by protoplast fusion using PEG 1000(50% w/v).

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High Frequency Embryogenesis and Plant Regeneration in Anther Cultures of Pepper (고추 약배양을 통한 고빈도 배발생 및 식물체 재분화)

  • 안민영;김용권;민성란;정원중;인동수;유장렬
    • Korean Journal of Plant Tissue Culture
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    • v.25 no.5
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    • pp.319-322
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    • 1998
  • Culture conditions for high frequency embryogenesis and plant regeneration in anther cultures of various F$_1$ hybrid and homozygous lines of pepper (Capsicum annuum L.) are described. Anthers pigmented less than halfway from the distal end were dissected from the flower bud in which petals elongated 2 mm higher than the receptacle. They were placed on Dumas medium supplemented with 0.1 mg/L 2,4-D and 0.1 mg/L kinetin. After four weeks of culture, embryos began to appear on anthers. After eight weeks of culture, frequencies of embryo formation reached up to 58.3%. Upon transfer to MS basal medium, greater than 95% of embryos developed into plantlets.

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Studies on Protoplast Regeneration and Reversion of Pleurotus ostreatus and Pleurotus florida (느타리섯과 사철느타리버섯의 원형질체(原形質體) 재생(再生) 및 환원(還元)에 관한 연구(硏究))

  • Yoo, Young-Bok;Peberdy, John F.;Cha, Dong-Yeul
    • The Korean Journal of Mycology
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    • v.13 no.2
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    • pp.79-82
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    • 1985
  • The experiment of protoplast regeneration and reversion were undertaken to provide a basic techniques for protoplast manipulation. Protoplasts of Pleurotus florida and Pleurotus ostreatus were reverted to normal hyphal growth and the reversion frequency of both fungal protoplasts were $0.24{\sim}3.19%$. Reversion medium stabilized with 0.6 M potassium chloride and sucrose was better than the other stabilized one. The protoplast reversion frequency was increased when various amino acid and vitamin compounds were added to the hypertonic mushroom complete agar medium.

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Callus Induction and Plant Regeneration in Hordeum spontaneum (Hordeum spontaneum에서의 callus 유기와 식물체 양생)

  • Jong-Yol Choi
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.4
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    • pp.466-470
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    • 1987
  • Immature embryos of Hordeum spontaneum were cultured on B5 and CI medium (Cheng's modified MS) to induce callus formation. CI media containing lmg/$\ell$ and 2mg/$\ell$ 2,4-D were more effective than B5 medium with lmg/$\ell$ 2,4-D for the initiation of callus. Total 883 calli were induced from 1,060 immature embryos plated. Callus induction frequency was 83%. Calli were transferred to differentiation media after one subculture to regenerate plants. Forty six plants were regenerated from 608 calli. Seventeen plants were chlorophyll deficient. There was no significant difference for plant regeneration among genotypes and media effects in calli which had been induced from immature embryos of seven types of trisomies. The overall regeneration frequency was 7.6%.

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High-frequency Plant Regeneration from Cultured Flower Bud Receptacles of Allium hookeri L.

  • Koo, Ja Choon
    • Horticultural Science & Technology
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    • v.32 no.5
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    • pp.694-701
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    • 2014
  • Allium hookeri L. (Alliaceae family) is an important ethnomedicinal plant native to the Himalayan region of Asia. The aim of this research was to establish a high-frequency plant regeneration system for in vitro propagation of A. hookeri. Among the tissue types examined, receptacle explants derived from immature flower buds showed the highest regeneration rate of shoots ($93.33{\pm}4.63%$), roots ($76.67{\pm}7.85%$), and calli ($80.00{\pm}7.43%$) when cultured on Gamborg B5 (B5) medium containing $10{\mu}M$ 6-benzylaminopurine (BA) + $1{\mu}M$ naphthalene acetic acid (NAA), $0.5{\mu}M$ BA + $5{\mu}M$ NAA, and $1{\mu}M$ BA + $10{\mu}M$ NAA, respectively. Shoot multiplication was superior when cultured in liquid rather than on solid medium and relatively high concentrations of BA, ranging from 5 to $10{\mu}M$. Efficient bulblet formation following root induction from shoot clumps was achieved with culture in liquid B5 medium containing 7% (w/v) sucrose. Regenerated bulblets were successfully acclimatized to ex vitro conditions with a greater than 95% survival rate. By this method, a maximum of 62 plantlets per receptacle could be propagated within 9 weeks of initial culture. The in vitro propagation system established in this study will promote A. hookeri biotechnology, including large-scale production of healthy and aseptic clones, preserving parental genotypes with desirable traits, and genetic manipulation to enhance medicinal value.

Evaluation on the Satisfaction of Urban Regeneration Projects - A case study of Yeong-ju - (도시재생사업의 만족도 평가 - 영주시를 대상으로 -)

  • Park, Hee-Jung;Byun, Tae-Geun;Lee, Sang-Ho
    • Journal of the Korean Regional Science Association
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    • v.34 no.3
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    • pp.3-11
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    • 2018
  • Urban regeneration is a worldwide challenging project, showing a great interest in the sector. In order for Korea's urban regeneration to be settled successfully in the early stage, it is necessary to analyze and review the opinions and business performance of the urban regeneration areas. The purpose of this study is to evaluate the urban regeneration planning factors affecting urban regeneration on the satisfaction of citizens, public administration and region. This study surveyed the residents and experts of the Yeongju city, Gyeongsangbuk-do, where urban regeneration is actively doing with active participation of residents and local government. Based on the data of the survey, this paper performed frequency analysis, correlation analysis and multiple regression analysis as a analytic methods. The results revealed that 'community factor' was the most important factor to the satisfaction of residents in the urban regeneration project in progress. In the final stage(at present), both 'community factor' (0.387) and 'physical factor'(0.454) were found to have a significant effect on satisfaction. While the satisfaction from 'the economic factor'(0.111) has slowed but it has increased with 'the physical factors' in the process of regeneration project, 'the social factors'(-0.007) shows a downward trend. If the role of social factors and community factors are supported at the beginning step of the urban regeneration project, the physical factors and economic factors are continued to lead a sustainable urban regeneration in the long term.