• Title/Summary/Keyword: Medium-to-high Frequency

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High frequency plant regeneration from zygotic-embryo-derived embryogenic cell suspension cultures of watershield (Brasenia schreberi)

  • Oh, Myung Jin;Na, Hye Ryun;Choi, Hong-Keun;Liu, Jang Ryol;Kim, Suk Weon
    • Plant Biotechnology Reports
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    • v.2 no.1
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    • pp.87-92
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    • 2008
  • An improved protocol for high frequency plant regeneration via somatic embryogenesis from zygotic embryo-derived cell suspension cultures of watershield (Brasenia schreberi) was developed. Zygotic embryos formed pale-yellow globular structures and white friable callus at a frequency of 80% when cultured on halfstrength MS medium supplemented with $0.3mg\;l^{-1}$ 2,4-D. However, the frequency of formation of pale-yellow globular structures and white friable callus decreased slightly with increasing concentrations of 2,4-D up to $3mg\;l^{-1}$, where the frequency reached ~50% of the control. Cell suspension cultures from zygotic embryoderived white friable callus were established using half-strength MS medium supplemented with $0.3mg\;l^{-1}$ 2,4-D. Upon plating of cell aggregates on half-strength MS basal medium, approximately 8.3% gave rise to somatic embryos and developed into plantlets. However, the frequency of plantlet development from cell aggregates was sharply increased (by up to 55%) when activated charcoal and zeatin were applied. Regenerated plantlets were successfully transplanted to potting soil and grown to normal plants in a growth chamber. The distinctive feature of this study is the establishment of a high frequency plant regeneration system via somatic embryogenesis from zygotic embryo-derived cell suspension cultures of water-shield, which has not been previously reported. The protocol for plant regeneration of watershield through somatic embryogenesis could be useful for the mass propagation and transformation of selected elite lines.

Development of Vibration and Noise Prediction Softwares for Vehicle Structures Using Power Flow Analysis (파워흐름해석법을 이용한 자동차 구조물의 진동/소음 예측 프로그램 개발)

  • Lee, Ho-Won;Hong, Suk-Yoon;Seo, Sung-Hoon;Kwon, Hyun-Wung;Park, Young-Ho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.391-397
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    • 2005
  • Power Flow Analysis(PFA) is used as the promising tools for the vibration and noise predictions of complex structures in medium-to-high frequency ranges. When the noise and vibration of a complex structure are analyzed, Power Flow finite Element Method combining PFA with FEM is efficient in vibration analysis, and Power Flow Boundary element Method combining PFA with BEM is usful in noise analysis. PFFEM software, PFADS has been developed for the vibration analysis of coupled system structures. Also, NASPFA, the noise analysis software based on PFBEM, has been developed. Through the several upgrades, the current version PFADS R3 and NASPFA R2 are used for the vibration and noise analysis of system structures in medium-to-high frequency ranges. In this paper, the structure and function of each software are explained, and the vibration and noise levels of vehicle structures predicted by each software are shown.

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Factors for high frequency plant regeneration in tissue cultures of Indian mustard (Brassica juncea L.)

  • Bhuiyan, Mohammed Shafi Ullah;Min, Sung-Ran;Choi, Kwan-Sam;Lim, Yong-Pyo;Liu, Jang-Ryol
    • Journal of Plant Biotechnology
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    • v.36 no.2
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    • pp.137-143
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    • 2009
  • An efficient system for high frequency plant regeneration was established through investigating various factors such as plant growth regulator combinations, explant types and ages, and addition of $AgNO_3$ influenced on shoot regeneration in Brassica juncea L. cv. BARI sarisha-10. Murashige and Skoog (MS) medium supplemented with 0.1 mg/L NAA (1-naphthaleneacetic acid) and 1 mg/L BA (6-benzyladenine) showed the maximum shoot regeneration frequency (56.67%) among the different combinations of NAA and BA. Explant type, explant age, and addition of $AgNO_3$ also significantly affected shoot regeneration. Of the four type of explants (cotyledon, hypocotyl, root, and leaf explants)- cotyledon explants produced the highest shoot regeneration frequency and hypocotyls explants produced the highest number of shoots per explant, whereas root explants did not produce any shoot. The cotyledonary explants from Four-day-old seedlings showed the maximum shoot regeneration frequency and number of shoots per explant. Shoot regeneration frequency increased significantly by adding $AgNO_3$ to the medium. Two mg/L $AgNO_3$ appeared to be the best for shoot regeneration with the highest shoot regeneration frequency (86.67%) and number of shoots per explant (7.5 shoots). Considerable variation in shoot regeneration from cotyledonay explants was observed within the B. juncea L. genotypes. The shoot regeneration frequency ranged from 47.78% for cv. Shambol to 91.11% for cv. Rai-5. In terms of the number of shoots produced per explant, B. juncea L. cv. Daulot showed the maximum efficiency. MS medium supplemented with 0.1 mg/L NAA showed the highest frequency of rooting. The regenerated plantlets were transferred to pot soil and grown to maturity in the greenhouse. All plants were fertile and morphologically identical with the source plants.

Interaction Between time of Nodal Explant Collection and Growth Regulators Determines the Efficiency of Morus alba Micropropagation

  • Hassanein A.M.;Galal A.A.;Azooz M.M.
    • Journal of Plant Biotechnology
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    • v.5 no.4
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    • pp.225-231
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    • 2003
  • The hormonal requirement suiting micropropagation of Morus alba during any season throughout the year was studied. Sprouting frequency from axillary buds of M. alba was greatly influenced by the time of explant collection, the highest value was achieved when nodal explants were collected at the end of bud dormancy period (late in March) and cultured on Murashige and Skoog (MS) medium supplemented with low concentration (0.5 mg/L) of BAP, kinetin or IBA (85-68%). In addition, they showed higher axillary bud sprouting on growth-regulators-free medium (49%) than others collected in autumn or winter and cultured on medium supplemented with various growth regulators (47-48%). Regardless of that period, young explants with greenish buds collected in summer exhibiting high sprouting frequency (66%) on MS medium supplemented with 0.5 mg/L kinetin and 0.5 mg/L GA3. Shoot multiplication via adventitious bud formation was achieved when the nodal explants were cultured on MS medium supplemented with 2 mg/L BAP and 0.2 mg/L IBA. Further multiplication via nodal explants of in vitro grown shoots was obtained on MS medium supplemented with 0.5 mglL BAP and 0.5 mg/L GA3. While half strength MS medium supplemented with low concentration (0.5 mg/L) of IBA, IAA or 2,4-D stimulated adventitious root formation, IBA was the best. After transfer the plantlets to the soil, acclimatization for three weeks was essential prerequisite for survival in high frequency (92%). Peroxidase activity is related to break of bud dormancy where maximum enzyme activity was detected when the lateral buds were induced to commence growth under field condition (early in spring) or in vitro.

High frequency plant regeneration system for Nymphoides coreana via somatic embryogenesis from zygotic embryo-derived embryogenic cell suspension cultures

  • Oh, Myung-Jin;Na, Hye-Ryun;Choi, Hong-Keun;Liu, Jang Ryol;Kim, Suk-Weon
    • Plant Biotechnology Reports
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    • v.4 no.2
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    • pp.125-128
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    • 2010
  • Culture conditions were established for high frequency plant regeneration via somatic embryogenesis from cell suspension cultures of Nymphoides coreana. Zygotic embryos formed pale-yellow globular structures and calluses at a frequency of 85.6% when cultured on half-strength Murashige and Skoog (MS) medium supplemented with 0.3 $mg\;l^{-1}$ of 2,4-D. However, the frequency of pale-yellow globular structures and white callus formation decreased slightly with an increasing concentration of 2,4-D up to 10 $mg\;l^{-1}$ with the frequency rate falling to 16.7%. Cell suspension cultures were established from zygotic embryo-derived calluses using half-strength MS medium supplemented with 0.3 $mg\;l^{-1}$ of 2,4-D. Upon plating onto half-strength MS basal medium, over 92.3% of cell aggregates gave rise to numerous somatic embryos and developed into plantlets. Regenerated plantlets were successfully transplanted into potting soil and achieved full growth to an adult plant in a growth chamber. The high frequency plant regeneration system for Nymphoides coreana established in this study will be useful for genetic manipulation and cryopreservation of this species.

Study on critical point of ZnCdSe by using Fourier analysis (Fourier 변환을 이용한 ZnCdSe 전이점 연구)

  • Yoon, J.J.;Ghong, T.H.;Kim, Y.D.
    • Journal of the Korean Vacuum Society
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    • v.16 no.6
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    • pp.458-462
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    • 2007
  • Spectroscopic ellipsometry is an excellent technique for determining dielectric function. To obtain critical point energy, standard analytic critical point expression is used conventionally for second derivatives of dielectric function which might increase high frequency noise than signal. However, reciprocal-space analysis offers several advantages for determining critical point parameters in optical and other spectra, for example the separation of baseline, information, and high frequency noise in low-, medium-, high-index Fourier coefficient, respectively. We used reciprocal Fourier analysis for removing noise and determining critical point of ZnCdSe alloy.

Optimum Conditions of pH and Ca2+ Concentration for Electrofusion of Tobacco Protoplasts (담배 워형질체의 전기융합을 위하 pH 및 Ca2+ 농도 최적조건 설정)

  • 오인숙;소상섭;김환규
    • KSBB Journal
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    • v.13 no.4
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    • pp.399-403
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    • 1998
  • This study was carried out to optimize the concentration of Ca2+ and pH of fusion medium which affected electrofusion frequency of protoplasts isolated from Nicotiana tabacum L. (cv. BY4) mesophyll cells and callus. The protoplasts were electrofused in the fusion media containing two different Ca2+ concentrations and three different pH regions. Fusion frequency was lower in the fusion medium containing only 13% mannitol as osmotic stabilizer. However, higher degree of fusion frequency (47.3%) was observed in the fusion medium containing 50mM CaCl2 at pH 10.5 than any other conditions. Cell viability was decreased by Ca2+ and high pH treatment in the fusion media, while fusion frequency was increased. It is concluded that Ca2+ is involved in electrofusion of protoplasts.

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A Protocol for High Frequency Plant Conversion from Somatic Embryos of Peanut (Arachis hypogaea L. cv. DRG-12)

  • Rani A. Raja;Padmaja G.
    • Journal of Plant Biotechnology
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    • v.7 no.3
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    • pp.187-193
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    • 2005
  • A protocol was developed for somatic embryogenesis with 100% induction rate from immature zygotic embryo axes of peanut (Arachis hypogaea L. cv. DRG-12) cultured on MS medium containing $18.09\;{\mu}M$ 2,4-D. The frequency of somatic embryogenesis (31.7%) as well as the number of somatic embryos induced per explant (6.6) decreased when the concentration of 2,4-D was increased to $72.4\;{\mu}M$. Morphologically abnormal somatic embryos were observed at a frequency of 43.3% on MS medium containing $72.4\;{\mu}M$ 2,4-D. Somatic embryos isolated from 30-day-old cultures of immature zygotic embryo axes exhibited precocious germination with varied responses when placed on MS basal medium with 3% sucrose. Maximum shoot induction (80.0%) was observed from somatic embryos isolated from 60-day-old cultures of immature zygotic embryo axes when placed as a clump rather than individually on MS medium supplemented with $26.63\;{\mu}M$ BA and $0.54\;{\mu}M$ NAA. Shoots developed from somatic embryos rooted with higher frequency (93.3%) on Blaydes' medium containing $5.4\;{\mu}M$ NAA.

Development of PFFEM, the new vibroacoustic analysis system in medium-to-high frequency ranges (중고주파에서의 새로운 진동해석시스템, PFFEM 개발연구)

  • Seo, Seong-Hoon;Hong, Suk-Yoon;Park, Do-Hyun;Kil, Hyun-Gwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2000.06a
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    • pp.325-333
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    • 2000
  • To predict vibrational energy density and intensity of partitioned complex system structures in medium-to-high frequency ranges, Power Flow Finite Element Method(PFFEM) programs for the plate elements are developed. The flexural, longitudinal and shear waves in plates are formulated and the joint element equations for multi-couped plates are fully developed. Also the wave transmission approach has been introduced to cover the energy transmission and reflection at the joint plate elements. Using the developed PFFEM program the energy density and intensity of the submarine and automobile shape structures are predicted with a harmonic point force at a single frequency.

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Research on Medium-power Wireless Power Transmission using Commercial Power Frequency (60Hz) (상용전원 주파수(60Hz)를 사용한 중전력 무선전력전송 연구)

  • Gi-Bum Lee
    • The Journal of the Korea institute of electronic communication sciences
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    • v.19 no.3
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    • pp.497-506
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    • 2024
  • In this paper, medium-power wireless power transmission is implemented using the commercial power frequency (60 Hz). Since general magnetic induction wireless power transmission devices use more than several tens of kHz, the commercial power frequency (60 Hz) cannot be used as is. Therefore an AC/DC converter is used to convert the 60 Hz power frequency into DC, and a high-frequency power amplifier is used to convert DC into several tens of kHz. In magnetic induction wireless power transmission, the AC/DC converter and high-frequency power amplifier are removed, and a extremely low frequency wireless power transmission(ELF-WPT) system using commercial frequency consisting of only transmitting resonance tank, transmitting coil, receiving resonance tank, and receiving coil is implemented, and verified through wireless power transmission experiments.