• Title/Summary/Keyword: Regeneration frequency

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The Process and Method to Set a Mountainous Scenic Site's Designated Area

  • Han, Gab Soo;Kim, Soonki;Ham, Kwang Min
    • Journal of Forest and Environmental Science
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    • v.36 no.1
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    • pp.47-54
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    • 2020
  • A "Scenic Site" is an official heritage category legally defined as a "scenic site of outstanding artistic value with excellent scenic views." However, the subjective interpretation of the term causes several problems. This study suggested a systematic, organized process of designating a listed area as a scenic site after careful and detailed quantitative and qualitative analysis. Indicators were identified for each of the two analyses, and then scored and weighted. Quantitative indicators were distributed within 5 points for each indicator. Water, which is a natural indicator, based on distance from river boundaries. Forest landscapes were assigned in consideration of forest physiognomy and age class. Land use was allocated in consideration of land cover type and, in case of development site, '-' score was assigned. Cultural heritage conservation area, which is historical and cultural indicator, was distributed by distance within a maximum of 500 meters. Visibility, an indicator of landscape value, was assigned according to the frequency of visibility. The weight of each indicator was calculated by considering the value of each item. The weight of distribution of cultural resources is relatively high, while other items were set the same. In case of land use, however, '-' score was given according to the grade. Qualitative indicators, on the other hand, were considered terrain, landscape zone, ownership, intellectual boundary, and land category. The applicability of the proposed process and method was examined by applying the existing methods and criteria used for designating scenic spots. Opinions of subject-matter experts were incorporated in the identification of the indicators and in the result review stage. In the future, it is necessary to apply this method while designating scenic sites so as to establish an objective, scientific designation process.

Sonolytical Decomposition of NHCs in Aqueous Solution (수계중 이환형 질소고리화합물(NHCs)의 초음파적 분해)

  • Yoo, Young-Eok;Maeda, Yasuaki
    • Journal of Environmental Science International
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    • v.16 no.4
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    • pp.393-397
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    • 2007
  • The sonolytic decomposition of NHCs(Nitrogen Heterocyclic Compounds), such as atrazine[6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine], simazine(6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine), trietazine(6-chloro-N,N,N'-triethyl-1,3, 5-triazine-2,4-diamine), in water was investigated at a ultrasound frequency of 200kHz with an acoustic intensity of 200W under argon and air atmospheres. The concentration of NHCs decreased with irradiation, indicating pseudo-first-order kinetics. The rates were in the range $1.06{\sim}2.07({\times}10^{-2}min^{-1})$ under air and $1.30{\sim}2.59({\times}10^{-2}min^{-1})$ under argon at a concentration of $200{\mu}M$ of NHCs. The rate of hydroxyl radicals(${\bullet}{OH}$) formation from water is $19.8{\mu}M\;min^{-1}$ under argon and $14.7{\mu}M\;min^{-1}$ under air in the same sonolysis conditions. The sonolysis of NHCs is effectively inhibited, but not completely, by the addition of t-BuOH(2-methyl-2-propanol), which is known to be an efficient ${\bullet}{OH}$ radical scavenger in aqueous sonolysis. This suggests that the main decomposition of NHCs proceeds via reaction with ${\bullet}{OH}$ radical; a thermal reaction also occurs, although its contribution is small. The addition of appropriate amounts of Fenton's reagent $[Fe^{2+}]$ accelerates the decomposition. This is probably due to the regeneration of ${\bullet}{OH}$ radicals from hydrogen peroxide, which would be formed from recombination of ${\bullet}{OH}$ radicals and which may contribute a little to the decomposition.

MAXILLARY SINUS AUGMENTATION WITH BOVINE BONE MINERAL(Bio-$Oss^{(R)}$) AND THE MAXILLARY TUBEROSITY (상악결절과 다공성 골 미네랄의 복합이식을 통한 상악동 골이식술)

  • Han, Ki-Deok;Chung, Il-Hyuk;Lee, Eun-Kyung;Suh, Je-Duck;Song, Seung-Il
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.4
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    • pp.391-396
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    • 2007
  • The aim of this study was to evaluate implant stability placed in the maxillary sinus which was augmented with bovine bone mineral(Bio-$Oss^{(R)}$) mixed with autogenous bone from the maxillary tuberosity. Maxillary sinus floor augmentation with the mixture of bovine bone mineral and autogenous maxillary tuberosity bone was performed in 30 maxillary sinuses, and 68 implants were placed at the time of sinus graft. After 6 months of implant placement abutments were connected and implant stability quotient(ISQ) was measured by radio frequency analysis(RFA). In addition, bone level changes was evaluated by taking periapical radiograph. During surgical procedures, no complication was observed, and all patients healed uneventfully. At 6 months the implant showed stable ISQ values. The marginal bone level changes around the fixtures was stably maintained through out the follow up period. This study confirmed that maxillary sinus floor augmentation with mixture of bovine bone mineral and maxillary tuberosity bone could be reliable for bone regeneration in subantral space.

The Effect of EA and TENS on GAP-43 Expression in Spinal Cord after Rat Sciatic Nerve Crush Injury (전침자극과 경피신경전기자극이 흰쥐 좌골신경 압좌손상 후 척수내 GAP-43 발현에 미치는 영향)

  • Lee, Hyun-Min;Park, Eun-Se;Kim, Min-Hee;Kim, Souk-Boum;Kim, Dong-Hyun;Kim, Jin-Sang
    • The Journal of Korean Physical Therapy
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    • v.18 no.1
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    • pp.65-73
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    • 2006
  • Purpose: The purpose of this study was to identify the effect of electroacupuncture(EA) and transcutaneous electric nerve stimulation(TENS) after sciatic nerve crush injury in rats. Methods: The EA for experimental group I (Exp I, n=15) and TENS for experimental group II (Exp II, n=15) was applied from post-injury day(PD) 1 to PD 14 after sciatic nerve injury using low frequency stimulator that gave electrical stimulation(15min/60Hz). In order observe the effect of EA and TENS, this study examined GAP-43 expression in rat lumbar spinal cord at the PD 1, PD 7 and PD 14. In addition, the stride length(SL) and toe out angle(TOA) were measured at the PD 7 and PD 4. Results; Exp I and Exp II had higher GAP-43 immunoreactivity than control group(PD 1, 7, 14). The SL of Exp I and Exp II were significantly higher than control group(PD 7, 14). The TOA of Exp I and Exp II were significantly lower than control group(PD 7, 14). Conclusion: EA and TENS application increased motor nerve recovery and expression of GAP-43 immunoreactivity after sciatic nerve crush injury. Therefore effect of TENS and EA had similar effect on nerve regeneration and functional recovery.

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High Frequency Somatic Embryogenesis and Plant Regeneration in Seedling Explant Cultures of Melon (Cucumis melo L.) (멜론(Cucumis melo L.) 유묘 절편으로부터 고빈도의 체세포배발생과 식물체 재분화)

  • 최필선;소웅영;조덕이;유장렬
    • Korean Journal of Plant Tissue Culture
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    • v.21 no.1
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    • pp.1-6
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    • 1994
  • Cotyledonary and hypocotyl explants of melon seedlings were cultured on Murashige and Skoog's (MS) medium supplemented with various concentrations of 2,4-Dichlorophenoxyacetic acid (2,4-D) and benzyladenine (B.A).Up to 22% of cotyledonary explants and 7%, of hypocotyl explants, respectively: Produced somatic embryos through intervening two types of calli: bright yellow compact (BYC) callus and pale-yellow compact (PYC) callus. BYC callus was capable of producing somatic embryos at initial culture, but it became necrotic as subrulhues proceeded. In contrast UC callus was incapable of producing somatic embryos during initial culture (first 6 weeks), but it became bright-yellow friable (BYF) callus with forming a few globular embryos after 2 months of subculture, indicating that the callus turned embryogenic. The embryogenic capacity of BYF maintained for over one year when the callus was sucultured at 4-week interval. Upon transfer onto MS basal medium the callus gave rise to numerous somatic embryos and subsequently converted to plantlets. Plantlets were transplanted to potting soil and grown to maturity in the phyotron.

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Plant Regeneration from Immature Zygotic Embryos of Stewartia koreana Nakai via Somatic Embryogenesis (노각나무(Stewartia koreana Nakai)의 미숙배로부터 체세포배발생에 의한 식물체 재분화)

  • 최은경;박학봉;김광수;이용기
    • Korean Journal of Plant Tissue Culture
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    • v.22 no.2
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    • pp.77-81
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    • 1995
  • When cultured on MS medium supplemented with 0.5 mg/L NAA alone or 1.0 mg/L 2,4-D and 0.5 mg/L BA, immature zygotic embryos of Stewartia koreana formed embryogenic calli and somatic embryos. In investigate effect of sucrose concentration on somatic embryo development, embryogenic calli were transferred to MS basal medium containing 1.5,3, 6 or 9% sucrose. The greatest frequency of somatic embryos was obtained on medium containing 6% sucrose. However addition of 1.5 or 9% sucrose to medium inhibited somatic embryo germination and development into normal plantlet After 5 weeks of hardening culture on medium containing 6% sucrose, somatic embryos were transferred to half strangth MS medium supplemented with 0.1% charcol, wherein these embryo developed into the normal plantlets.

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Plant Regeneration from Protoplasts of Suspension Cultured Cells in Arabidopsis thaliana (애기장대(Arabidopsis thaliana) 현탁배양세포의 원형질체로부터 식물체 재분화)

  • 김명덕;김준철;진창덕;임창진;한태진
    • Korean Journal of Plant Tissue Culture
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    • v.27 no.2
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    • pp.125-131
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    • 2000
  • Protoplasts of Arabidopsis thaliana were easily isolated from the shoot-forming (SF) suspension-cultured cell clusters with 4 hours-shaking condition (40 rpm) on CPD enzyme solution containing 1% cellulase R-10, 0.25% pectolyase Y-23 and 0.5% driselase. Protoplasts were cultured on liquid KAO medium supplemented with 1 mg/L 2,4-D, 0.5 mg/L kinetin, 200 mg/L spermidine and 68 g/L glucose. Also, protoplasts were cultured on 0.2 $\mu$M membrane filter placed onto CP solid medium containing the suspension cells as feeder cells in the dark at $25^{\circ}C$ for 4 weeks. Protoplast-derived-SF calli were cultured on MS medium containing 0.05 mg/L IAA, 7 mg/L 2 ip and 30 g/L sucrose under the continuous illumination for four weeks. The frequency of shoot formation was about 60%. The regenerants were transferred into potting soil to grow mature plants. The regenerants formed the silques with seeds after 8 weeks of cultures.

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Decomposition of Nitogen Heterocyclic Compounds(NHCs) in Aqueous Solution by Sonication

  • Yoo, Young-Eok;Maeda, Yasuaki
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2003.11a
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    • pp.171-176
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    • 2003
  • The sonolytic decomposition of NHCs, such as atrazine[6-chloro-N-ethyl-N' -(1-methylethyl)-1,3,5-triazine-2,4-diamine], simazine( 6-chloro-N,N' -diethyl-l ,3,5-triazine-2,4-diamine), trietazine(6-chloro-N,N,N'-triethyl-l,3,5-triazine-2,4-diamine), in water was investigated at a ultrasound frequency of 200kHz with an acoustic intensity of 200W under argon and air atmospheres. The concentration of NHCs decreased with irradiation, indicating pseudo-first-order kinetics. The rates were in the range 1.06∼2.07 (x10/sup -3/ min/sup -1/) under air and 1.30∼2.59(x10/sup -3/ min/sup -1/)under argon at a concentration of 200μM of NHCs. The rate of hydroxyl radicals(·OH) formation from water is 19.8μM min/sup -1/ under argon and 14.7 μM min/sup -1/ under air in the same sonolysis conditions. The sonolysis of NHCs is effectively inhibited, but not completely, by the addition of t-BuOH(2-methyl-2-propanol), which is known to be an efficient ·OH radical scavenger in aqueous sonolysis. This suggests that the main decomposition of NHCs proceeds via reaction with ·OH radical; a thermal reaction also occurs, although its contribution is small. The addition of appropriate amounts of Fenton's reagent [Fe/sup 2+/] accelerates the decomposition. This is probably due to the regeneration of ·OH radicals from hydrogen peroxide, which would be formed from recombination of ·OH radicals and which may contribute a little to the decomposition.

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Development of L-Lysine Producing Strains by Intergeneric Protoplast Fusion of Brevibacterium flavum and Corynebacterium glutamicum (Brevibacterium flavum과 Corynebacterium glutamicum의 이속간 원형질체 융합에 의한 L-라이신 생산균주 개발)

  • Kyung, Ki-Cheon;Lim, Bun-Sam;Lee, Se-Yong;Chun, Moon-Jin
    • Microbiology and Biotechnology Letters
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    • v.13 no.3
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    • pp.279-283
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    • 1985
  • As a method of breeding L-lysine producing strains, the intergeneric protoplast fusion between Brevibacterium flavum and Corynebacterium glutamicum was performed. As a results, Brevibacterium flavum ATCC 21528 R showed 99% of protoplast formation and 10% of regeneration frequencies when treated with 400$\mu\textrm{g}$/$m\ell$ of lysozyme for 12hrs. In Corynebacterium glutamicum ATCC 21514 S, 99% and 12% were obtained by treatment of 300$\mu\textrm{g}$/$m\ell$ lysozyme for 12 hrs. In intergeneric protoplast fusion between Brevibacterium flavum ATCC 21528 R and Corynebacterium glutamicum ATCC 21831 S, 1.0$\times$10$^{-6}$ of recombinant frequency per regenerable cells was observed by use of PEG 6000, 30%(w/v). Among the strains obtained KR$_{43}$ strain showed 12% higher productivity of L-lysine than the parental cell. Then, the activity of aspartokinase of KR$_{43}$ was about 13% higher than the parental cell.

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Formation and Fusion of Protoplasts from the Cellulolytic Fungi, Aspergillus niger MAN-831 and Aspergillus wentii MAW-538 (Cellulase를 생산하는 Aspergillus niger MAN-831과 Aspergillus wentii MAW-538의 원형질체 형성 및 융합)

  • 박석규;이상원;문일식;손봉수;강성구
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.24 no.6
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    • pp.964-969
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    • 1995
  • For the effective utilization of cellulosic biomass, conidial protoplast fusion between Aspergillus niger MAN-831(${\beta}-glucosidase$) and A. wentii MAW-538(CMCase and avicelase), which produced potently cellulolytic enzymes was carried out. Optimal conditions for formation and regeneration of protoplast were conidiospore age-5 dyuas. $2-DG-30\mu\textrm{g}/ml$, preincubation time-4 hours, osmotic stabilizer-0.7M KCl, novozyme(7mg/ml)+driselase(2.5mg/ml) and reaction time of enzyme-5 hours. Optimal conditions for protoplast fusion were obtained by treatment of protoplasts with 15mM CaCl2 and 25% polyethylene glycol 4000(pH 6~7) as fusogenic agent at $36^{\circ}C$ for 25~30 minutes. The frequency was then $7.94{\times}10^{-4}$. CMCase, avicelase and ${\beta}-glucosidase$ activity of fusant F-208 strain was 1.5, 1.3, 1.2 times higher than those of parental strains, respectively.

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