• Journal of Plant Biotechnology
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• v.1 no.2
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• pp.117-121
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• 1999

Effects of jasmonic acid treatment, UV-B and white light treatment on the anthocyanin biosynthesis and cell growth were investigated using the cell suspension culture system of grape (Vitis vinifera L.). Cell growth was not affected by white light irradiation, while it was remarkably suppressed by UV-B irradiation from 8 to 32 h. Anthocyanin accumulation dramatically increased after 16 h from irradiation of UV-B. Simultaneous treatment of jasmonic acid and UV-B increased anthocyanin accumulation by 10-fold. The cell division was restored when anthocyanin was abundantly accumulated after 32 h from UV-B irradiation. Optimum concentration of jasmonic acid was found to be 5 uM for maximum accumulation of anthocyanin. Application of jasmonic acid to grape suspension cells rapidly induced the expression of CHS gene after 2 h from treatment and showed maximum level at 32 h. Simultaneous treatment of jasmonic acid and light also induced CHS gene expression after 2 h, but the maximum level of CHS transcript was observed at 16 h with white light and 8 h with UV-B exposure. The synergistical effects could be explained by the defense mechanism that UV irradiation is mediated in part by alterations in JA and its signaling pathway.

• Food Science and Preservation
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• v.6 no.1
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• pp.23-28
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• 1999

Commercial red ginseng, which was manufactured for the past 6 years, showed a microbial level of 2.0${\times}$10\ulcorner to 7.2${\times}$10\ulcorner CFU/g of total aerobic bacteria and molds. The moisture content of commercial products was ranged from 13.54 to 17.26%, which were higher than that of the product standard, 14%. Irradiation of red ginseng at 2.5 kGy resulted in the reduction of microorganisms contaminated to below the detectable level. Irradiation prevented mold growth on red ginseng during storage at RH 90% and 25$^{\circ}C$; molds were found at the 72nd day after storage in 2.5 kGy-irradiated sample, while 41st day in the nonirradiated control. At this point of time, irradiated samples showed an increased level of moisture content required for mold growth, 22.2% in 2.5 kGy group and 21.5% in control group. Based on the above results, microbiological qualities of red ginseng could be effectively improved by the optimum dose of irradiation, which was expected to secure the quality stability of red ginseng during distribution under the high-moistured conditions.

• Korean Journal of Medicinal Crop Science
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• v.14 no.6
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• pp.360-366
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• 2006

To investigate the effect of culture conditions on growth and ginsenosides accumulation, we cultured the ginseng hairy root under three different media, white light or ultra-violet irradiation. The MS/B5 medium containning MS basal salt and B5 vitamin was good for the growth and ginsenoside accumulation. The light during the culture period of ginseng hairy root was irradiated. The growth was abundant in the ginseng hairy root cultured in dark. But the ginsenosides accumulation was higher than in the ginseng hairy root cultured in the light irradiation. When the ginseng hairy root was cultured in 20 L bioreactor, the ginsenosides accumulation was observed at 34% higher than the hairy root cultured in dark. UV irradiated the ginseng hairy root during the culture period. The long time irradiation of UV was caused decreasing the growth of ginseng hairy root, but the accumulation of ginsenosidess was increased as to the irradiated time.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.20 no.1
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• pp.39-48
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• 2024

Research reactors are operated under ambient temperature and atmospheric pressure, which is much less severe conditions compared to those in typical nuclear power plants. Due to the high temperature, heat resistant materials such as austenite stainless steel should be used for the reactors in typical nuclear power plants. Whereas, as the effect of temperature is low for research reactors, materials with high resistance to neutron irradiation, such as zircaloy and beryllium, are used. Therefore, these conditions should be considered when performing integrity assessment for research reactors. In this study, a computational technique through finite element (FE) analysis was developed considering the operating conditions and materials of research reactor when conducting integrity assessment. Neutron irradiation analysis techniques using thermal expansion analysis were proposed to consider neutron irradiation growth and swelling in zirconium alloys and beryllium. A user subroutine program that can calculate the strain rate induced by neutron irradiation creep was developed for use in the commercial analysis program Abaqus. To validate the proposed technique and the user subroutine, FE analysis results were compared with hand-calculation results, and showed good agreement. Consequently, developed technique and user subroutine are suitable for evaluating structural integrity of research reactors.

• Korean journal of applied entomology
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• v.4
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• pp.19-24
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• 1965

In an attempt to find a satisfactory environmental factors which facilitate abundant conidial production of Piriculariaoryzae Cav. on tomato juice media, various environmental factors were studied for their effect on sporulation and mycelial growth of the fungus. Those factors were conditions of irradiation, color of light, age of culture and pH of the media. l) Continuous exposure to fluorescent light (Mitsubish FL-20-35 W) produced more conidia and much mycelial growth than did intermittent photoperiods and darkness. 2) Of 3 cellophane filters and direct exposure to fluorescent light used, conidia were produced best under the direct exposure to the light. Conidial production in color filter conditions sequently decreased with red, yellow and blue. Growth of mycelium was not significantly different within colors. 3) Periodic irradiation of 12-hour unit brought about zones on mycelial growth no matter what the color filter was used. 4) Older cultures responding to the light were more stimulated by light than were the younger one in the conidia production, but maximum production of conidia was 48 hours of age in this case. 5) Color of the mycelial mat and the aerial mycelium seemed to have a close relation to the production of conidia. The more darkness of the mycelial mat was produced the more conidia and the much aerial mycelium was produced the least conidia. The color of mycelium was more dark under the continuous irradiation than continuous darkness, while the periodic irradiation showed intermediate effect. 6) The concentration of hydrogen ion for growth and sporulation of the fungus was investigated the ranges between 5 and 9. The best pH for the fungus was also noted at 7. whereas the below of pH 4 was not occurred any mycelial growth and sporulation.

• Korean Journal of Agricultural Science
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• v.39 no.4
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• pp.459-466
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• 2012

The objective of this study is to observe growth pattern of grand rapids(lettuce) according to different dexperimental conditions for minimizing its growth period such as composition of nutrient, irradiation time of light source and cultivation mode. The culture of water spray type using seeds of grand rapids was performed during growth period of total 50 days. Experimental conditions consist of five compositions of nutrient (PW 0.5 mS/cm, PW 1.0 mS/cm, PY 0.5 mS/cm, PY 1.0 mS/cm, PW 2.0 mS/cm) and three irradiation times of light source (12h(on) / 12h(off), 18h(on) / 06h(off), 24h(on) / 00h(off)). Illumination was adjusted to ratio of 7:1:1 of red, blue and white color, respectively. Indoor environmental condition for cultivating grand rapids is as follows: temperature (19-$22^{\circ}C$), relative humidity (60-70%) and carbon dioxide (1,000-1,200 ppm). The data were obtained from five iteration tests. The maximum growth level was observed in the experimental condition of 18 hr(on) / 06 hr(off) and PY 1 mS/cm for 1st week of cultivation period, 24 hr(on) / 00 hr(off) and PY 1mS/cm for 2nd week of cultivation period, and 24 hr(on) / 00hr(off) and PW 1 mS/cm for 3rd week of cultivation period, respectively. On the contrary, the minimum growth level was observed in the experimental condition of 18 hr(on) / 06 hr(off) and PW 0.5 mS/cm for 1st week of cultivation period, 12 hr(on) / 12 hr(off) and PW 0.5 mS/cm for 2nd week of cultivation period, and 12 hr(on) / 12 hr(off) and PY 0.5 mS/cm for 3rd week of cultivation period, respectively. Based on the results obtained from this study, it is concluded that the growth level of grand rapids varied with different irradiation time of light source and composition ratio of nutrient according to cultivation period.

• Journal of Korea Foresty Energy
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• v.19 no.1
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• pp.1-6
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• 2000

This study was carried out to investigate the growth responses of Pinus densiflora seedlings to enhanced UV-B environment for 16 weeks in the field condition. The seedlings were treated with one of three levels of UV-B dosages - ambient UV-B, ambient + 3.2, and ambient + 5.2 KJ m$^{-2}$day$^{-1}$ and the irradiation was performed at the stage before the germination, the fully expanded cotyledon, and the primary needles grown more than 0.8cm in length of the seedlings, respectively. Enhanced UV-B irradiation reduced the height and the root collar diameter growth, and dry mass production of the seedling, and T/R ratio was increased by the UV-B treatment. Difference in seedling growth was observed by difference in time of the UV-B treatment. Among the seedlings which were treated with ambient - 3.2 KJ m$^{-2}$day$^{-1}$, height and root collar diameter growth was relatively high in the seedling received the UV-B treatment at the stage before the germination. The lowest dry mass production was observed in the seedlings received the UV-B at stage of cotyledon both in two levels of enhanced UV-B treatment. Chlorophyll concentration was reduced by enhanced UV-B irradiation, and chlorophyll a/b ratio was increased by the UV-B treatment.

• Korean Journal of Environmental Biology
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• v.25 no.2
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• pp.107-114
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• 2007

Radiation at very low doses frequently has a stimulating or hermetic effect on growth of organism. Effects of growth and survival rate on various dose of gamma irradiation in the farm culture of juvenile abalone (Haliotis discus hannai) were determined in Hallim (Jeju) from February 2004 to January 2005. The initial shell length of abalone juveniles in this study was average $3.45{\pm}0.4cm$. A change of growth after irradiation $(0{\sim}20Gy)$ was observed for 48 weeks. The highest growth rate was observed in 4 Gy-irradiated group and the lowest growth rate was observed in 20 Gy-irradiated group. The additional research about biochemical changes on juvenile abalone after irradiation should be accomplished. Continuous study for gamma radiation-induced hormesis on growth and metabolism of juvenile abalone will further induce the creation of value in ocean industry.

• Culinary science and hospitality research
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• v.8 no.3
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• pp.249-257
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• 2002

Gamma irradiation(1~10 kGy) was applied to chicken for the evaluation of their microbiological safety. In 3kGy-irradiated sample, the initial level of microbial contamination in chicken was 1.8$\times$10$^4$CFU/g (Coliforms), 2.2$\times$10$^3$CFU/g(Salmonella) and 2.7$\times$10$^3$CFU/g(Listeria), All kinds of contaminated microorganism were sterilized by 7kGy-irradiation. Also, irradiation followed by freeze storage at the same time was very effective in inhibiting bacterial growth. The pH was slightly increased during storage period and titratable acidity decreased. However, no significant changes in pH and acidity were observed by gamma irradiation.

• Horticultural Science & Technology
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• v.32 no.4
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• pp.507-516
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• 2014

The present study was conducted to determine the effect of electron beam irradiation on control of Botrytis cinerea and postharvest quality of cut roses. Electron beam doses of 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2, 10, and 20 kGy were applied with a 10-MeV linear electron beam accelerator (EB Tech, Korea). Electron beams inhibited spore germination and mycelial growth of B. cinerea with increasing irradiation doses. Conidia of B. cinerea were more tolerant to irradiation than were mycelia: the effective irradiation doses for 50% inhibition ($ED_{50}$) of spore germination and mycelial growth were 2.02 kGy and 0.89 kGy, respectively. In addition, electron beam irradiation was more effective in reducing mycelial growth of B. cinerea at $10^{\circ}C$ than at $20^{\circ}C$. Analysis of in vivo antifungal activity revealed that elevated irradiation doses exhibited increased control efficacy for tomato gray mold. Flower longevity and fresh weight of cut roses decreased when the irradiation dose was increased. In addition, flower bud opening tended to be inhibited in a dose-dependent manner. Although 'Decoration', 'Il se Bronze', 'Queen Bee', and 'Revue' roses tolerated and maintained overall postharvest quality up to 0.4 kGy, 'Vivian' did not, demonstrating that the irradiation sensitivity of cut roses varies according to cultivar.