• Title/Summary/Keyword: regeneration rate

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Protoplast Preparation and Regeneration from Young Hyphae of the Citrinin Producing Fungus Monascus ruber

  • Norlha, Tenzin;Lee, In-Hyung
    • Food Science and Biotechnology
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    • v.14 no.4
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    • pp.543-546
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    • 2005
  • Optimized conditions for protoplast preparation and regeneration from young hyphae of Monascus ruber were established. Heat shock treatment of spores gave rapid and synchronized germination. Spores collected from cultures grown for 7-8 days at $30^{\circ}C$ were germinated until over 70% germ tubes reached to 3-5 spore length. Enzymatic digestion of young hyphae was optimal with 50 mg/mL Glucanex in 0.1 M sodium citrate buffer containing 0.8 M mannitol as an osmotic stabilizer. Regeneration rate was around 10% when 0.8 M sorbitol was used as an osmotic stabilizer in regeneration medium. These conditions will be applied in genetic study of M. ruber that produces citrinin at high level and thus is good model strain for molecular genetic dissection of citrinin biosynthesis.

Correlations Between Polyamine and Adventitious Shoot Regeneration from Populus Leaf Segments (포플라 잎절편의 부정아 분화와 Polyamine 함량의 연관성)

  • 김성호
    • Journal of Plant Biology
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    • v.36 no.1
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    • pp.1-8
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    • 1993
  • Polyamine contents and the activities of their main biosynthetic enzymes, arginine decarboxylase (ADC) and ornithine decarboxylase(ODC), were investigated in Populus leaf segments during adventitious shoot regeneration with the addition of 1 millimolar polyamine synthesis inhibitors. From the study of polyamine synthesis inhibitors, ODC was found to be the principal route of polyamine biosynthesis in adventitious shoot regeneration of Populus leaf segments. The ADC inhibitor difluoromethyl arginine(DFMA) and ODC inhibitor difluoromethyl ornithine(DFMO) strongly reduced the putrescine content. On the contarary, DCHA, an inhibitor of spermidine synthase, increased it. Spermidine content was decreased with the treatment of each polyamine synthesis inhibitor, but the inhibitory effect of DCHA was stronger than any other polyamine inhibitor. The decreased polyamine level by polyamine synthesis inhibitors was restored with the exogenously applied polyamine. Comparing the polyamine contents with the adventitious shoot regeneration rate, were observed a close correlation between spermidine content and adventitious shoot regeneration of Populus leaf segments.

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Ecological Modeling for Estimation of Environmental Characteristics in Masan Bay

  • Kim, Dong-Myung
    • Journal of Environmental Science International
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    • v.12 no.8
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    • pp.841-846
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    • 2003
  • The ecosystem model was applied to estimate the regional distribution of the net production(or consumption) of phytoplankton and the net uptake(or regeneration) rate of nutrients in Masan Bay for scenario analysis to find a proper management plan. At the surface level, net production of phytoplankton is 200 mgC/㎡/day at the entrance of the bay, and 400∼1000 mgC/㎡/day at the center of the bay. The inner area of the bay showed more than 2000 mgC/㎡/day. All areas of the bottom level have a net consumption, with the center of the bottom level showing more than 600 mgC/㎡/day. For dissolved inorganic nitrogen, the results showed a net uptake rate of 100∼900 mg/㎡/day at the surface level. It showed that the net regeneration is above 50 mg/㎡/day at the bottom level. For dissolved inorganic phosphorus, the net uptake rate showed 10.0∼80.0 mg/㎡/day at the surface level, and the regeneration rate showed 0∼20.5 mg/㎡/day at the bottom level. Therefore, in order to control the water quality in Masan Bay, it is important to consider the re-supplement of nutrients regenerated in the water column.

Genotype Effect on Somatic Embryogenesis and Plant Regeneration of 15 Aralia elata (두릅나무 15개체의 체세포배 유도 및 식물체 재분화에 미치는 유전자형의 효과)

  • 문흥규;홍용표;김용욱;이재순
    • Korean Journal of Plant Tissue Culture
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    • v.28 no.3
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    • pp.129-134
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    • 2001
  • Winter bud explants from 15 individual angelica tree (Aralia elata) were cultured in vitro to find out optimal conditions for somatic embryo induction as well as plant regeneration. Calli are induced and grown on MS medium supplemented with 1.0 mg/L 2,4-D for 4 weeks and subcultured on a half-strength MS medium without phytohormones to induce somatic embryos. Inter-simple sequence repeat (I-SSR) markers were analyzed with total DNAs extracted from the trees. Genotype effects on somatic embryo induction were examined by cluster analysis. Callus induction rate varied from 58.5 to 100% among the genotypes. Somatic embryo induction rate also greatly varied from 0 to 100% among the genotypes. There was a significant difference in somatic embryo induction rate even among the individual trees that showed close genetic relationships each other. This suggested that somatic embryo induction rate in Aralia elata be influenced by a few major specific genes rather than whole genomic similarity among individual trees. Four individuals of Ulneong-7, Cheju-1, Shingu and China, which are recalcitrant to somatic embryo induction, turned out to have a close genetic relationship, suggesting that both physiological and genetic factors affect somatic embryo induction. The results suggest that genotype selection be the most important factor to achieve an efficient propagation, although cultural optimization through medium and explant manipulation may also play crucial roles in somatic embryogensis as well as plant regeneration of these species.

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Research on the Performance of a Solar Air Conditioning System using a Liquid Desiccant in Summer (액체흡수제 이용 태양열 공조시스템의 하계 능력에 관한 연구)

  • Choi, K.H.;Yoon, J.I.;Kim, B.C.
    • Journal of the Korean Solar Energy Society
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    • v.22 no.2
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    • pp.33-38
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    • 2002
  • In order to find out whether solar air conditioning system could be applied to building or not, the performance and evaluation on thermal environment of the system suggested was done during summer. A solar model house was constructed to find out the performance and thermal environment evaluation when it actually operated outside. As a result, regeneration rate increased rapidly when LiCl solution temperature was over $50^{\circ}C$ and the regeneration rate was $13\sim15kg$ during 9 hours operation. Furthermore the dehumidification rate was 12kg at maximum during 10 hours operating of a dehumidifier and indoor temperature and relative humidity was $28.4^{\circ}C$ and 39.1% in average respectively. On evaluation of thermal environment during summer, PMV value was slightly high, but thermal sensation vote was 71% within the comfort zone.

Medium Composition Affecting In Vitro Plant Regeneration and Acclimation of Pteris cretica 'Wilsonii' (Pteris cretica 'Wilsonii'의 기내 식물체 재생에 미치는 배지구성물질의 영향 및 기외순화)

  • Shin, So-Lim;Lee, Cheol-Hee
    • Korean Journal of Plant Resources
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    • v.22 no.5
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    • pp.394-402
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    • 2009
  • Adventitious shoots were induced from pinnae, petiole and rhizome in Pteris cretica 'Wilsonii' in order to develop the efficient mass propagation method, using in vitro culture. Only homogenized rhizome segments could regenerate young sporophytes. Efficient regeneration of multiple shoots was obtained on the one-eighth strength MS medium containing 1% sucrose, and $50mg{\cdot}L^{-1}$ $NaH_2PO_4$. To achieve higher rate of regeneration from rhizome segments, rhizome segments were exposed to growth regulators for 2 months and then subcultured on hormone-free medium. The greatest shoot regeneration was obtained by $1{\mu}M$ kinetin with $5{\mu}M$ NAA. BA was effective in formation of GGB (kind of meristems), but they showed low shoot regeneration rate. Plants obtained from present experiments were transplanted to examine good environmental conditions for acclimation. Juvenile plants obtained by the one-eighth strength MS medium showed highest survival rate and vigorous growth at the seedling stage.

Clinical evaluation of $Br{\aa}nemark$ Ti-Unite implant and ITI SLA implant in the post maxillary area with sinus elevation technique. (상악동 거상술을 이용하여 구치부에 식립된 $Br{\aa}nemark$ Ti-Unite와 ITI SLA 임플란트의 임상적 평가)

  • Hong, Seong-Bae;Chai, Gyung-Joon;Jung, UI-Won;Kim, Chang-Sung;Chim, Joon-Sung;Choi, Seong-Ho;Cho, Kyoo-Sung;Kim, Chong-Kwan
    • Journal of Periodontal and Implant Science
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    • v.35 no.4
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    • pp.813-822
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    • 2005
  • The predictable outcome of implant placement in the atrophic maxilla with sinus floor elevation procedure(osteotome sinus floor elevation technique and window opening technique) is well documented. Aim of this study was to evaluate the efficacy of $Br{\aa}nemark$ Ti-Unite implant system and ITI SLA implant system placed in the atrophic posterior maxilla with sinus floor elevation procedure. Eighty patients received placement of $Br{\aa}nemark$ Ti-Unite implants(195 implants) in their atrophic posterior Maxilla with sinus floor elevation procedure(153 osteotome sinus floor elevation technique and 42 window opening procedure). Fifty patients received placement of ITI SLA implants(83 implants) in their atrophic posterior Maxilla with sinus floor elevation procedure(77 osteotome sinus floor elevation technique and 6 window opening procedure). Chart review were taken from each patient. The total failed implants were seven and the total implant survival rate was 96.4% in $Br{\aa}nemark$ Ti-Unite system. The total failed implants were one and the total implant survival rate was 98.8% in ITI SLA system. The implant survival rate with osteotome technique was 96% and 97.6% with window opening in $Br{\aa}nemark$ Ti-Unite system. The implant survival rate with osteotome technique was 98.7% and 100% with window opening. The implant survival rate with osteotome technique was 96% and 97.6% with window opening in ITI SLA system. The results of this evaluation show that the placement of $Br{\aa}nemark$ Ti-Unite system as well as ITI SLA system is a reasonable treatment option for patients with the atrophic posterior maxillary area.

Effect of picloram and 2,4-D on plant regeneration from mature and immature embryos of moroccan durum wheat varieties

  • Ahansal, Khadija;Aadel, Hanane;Udupa, Sripada Mahabala;Gaboun, Fatima;Abdelwahd, Rabha;Ibriz, Mohammed;Iraqi, Driss
    • Journal of Plant Biotechnology
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    • v.49 no.2
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    • pp.131-138
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    • 2022
  • An efficient genetic transformation protocol is a fundamental requirement for high regeneration capacity from cultivated durum wheat (Triticum durum) varieties. In this study, wereportedtheeffectsoftwoauxins,2,4-dichlorophenoxyaceticacid(2,4-D)and4-amino-3,5,6-trichloropicoli nicacid(picloram), at a concentration of 2 mg/Laloneandincombination on the embryogenic callus and plantlet regeneration of four durum wheat varieties (Amria, Chaoui, Marouane, and Tomouh) using mature embryos (MEs) and immature embryos (ImEs). Significanteffectsofvariety,culturemedium(theauxinused),andvariety-mediuminteraction were observed on the callus weight and plantlet regeneration of both MR and ImE explants. The medium used for callus induction significantly affected plantlet regeneration (p < 0.001). Comparedto2,4-D, picloram led to a higher plantlet regeneration rate in both ME and ImE explants (19.8% and 40.86%, respectively). Plantlet regeneration also varied significantly depending on the variety and medium used. PicloramledtohighplantletregenerationofbothME and ImE explants in all varieties except Tomouh, which showed high plantlet regeneration of ME explants in 2,4-D. A comparison of ME and ImE responses indicated that ImEs are the best explants for high plantlet regeneration in durum wheat. Ourfindingssuggestthatpicloramisthebestauxin and should be used instead of 2,4-D due to its positive effect on increasing plant regeneration of durum wheat ME and ImE explants.

A retrospective clinical study of survival rate of the ITI $TE^{(R)}$ implant (ITI $TE^{(R)}$ 임플란트의 생존율에 관한 후향적 임상 연구)

  • Suh, Hyun-Kee;Chae, Gyung-Joon;Jung, Ui-Won;Kim, Chang-Sung;Cho, Kyoo-Sung;Choi, Seong-Ho;Chai, Jung-Kyu;Kim, Chong-Kwan
    • Journal of Periodontal and Implant Science
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    • v.36 no.3
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    • pp.673-682
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    • 2006
  • Recent study shows that implant design has a great impact on initial stability in bone. The ITI $TE^{(R)}$ implant, designed originally for immediate placement has a tapered/ cylindrical form which fits the anatomical shape of the natural alvelous or tooth root. The increased diameter at the collar region coupled with more threads lead to more bone contact and enhanced stability. The aim of this retrospective study is to evaluate the clinical use and the efficacy of recently introduced ITI TE implant with a new macro-design. The following results are compiled from 139 patients who received ITl TE implant surgery at the periodontal department. of Yonsei University Hospital between July 2002 and September 2005. 1. 139 patients received 173 ITl $TE^{(R)}$ implants in their maxilla and mandible (Mx 82, Mn 91). Posterior area accounted for 84% of the whole implant surgery, 2. In the distribution of bone quality, type III(41,0%) was the most, followed by type IV(41,0%) and type II (27.7%). As for the bone quantity, type B(43.9%) was the most, followed by type C(42.2%), type D(12.2%) and type A(1.7%). 3. 125 implants(83.9%) were treated by single crown, which accounted for the majority. 4, The total implant survival rate was 100% after a mean follow-up period of 21.2 months. This preliminary data with ITl $TE^{(R)}$ implant showed excellent survival rate although the majority of implants evaluated in this study were placed in the posterior region of the jaw and compromised sites.

Deforestation and Forest land Use in Côte d'Ivoire: Policy and Fiscal Instruments

  • Djezou, Wadjamsse Beaudelaire
    • Journal of Forest and Environmental Science
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    • v.32 no.1
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    • pp.55-67
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    • 2016
  • This paper investigated policies that drive the sustainable management of Ivorian forest which disappear at an annual rate of 250000 hectares. Based on an inter-temporal model for optimum allocation of forest land to three competing uses, the article found that sustainability depends on the incentive structure, of which forest taxes and fees are a key, though obviously not the sole, component. The study proposed to increase the area fee level by accounting for environmental externalities generated by forest harvesters and farmers. The paper showed that the area fee is a decreasing function of the forest natural rate of regeneration and the reconversion rate of agricultural surfaces. Finally, at the given forest natural rate of regeneration and the reconversion rate of agricultural surfaces, the model argued that the area fee need to be progressive (arithmetic progression) in the context of ecological equilibrium break while it should remain constant in normal situation.