• Korean Journal of Environmental Agriculture
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• v.19 no.4
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• pp.328-331
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• 2000

Maize (Zea mays L. cv. kosungjaerae and cv. youngwoljaerae) seeds were irradiated with the dose of $0.5{\sim}20$ Gy by $^{60}Co\;{\gamma}-ray$ radiation to investigate the effect of the low dose ${\gamma}-ray$ radiation on the germination rate, early growth and yield. The low dose radiation was able to improve the germination rate and early growth in maize, but the optimal radiation doses were different depended on kinds of cultivars. High stimulatory effect in early growth of maize was observed in 2 Gy irradiation group of kosungjaerae cultivar and in 12 Gy irradiation group of youngwoljaerae cultivar. The optimal radiation dose for the enhancement of yield and yield components in maize was 8 Gy in kosungjaerae cultivar and $4{\sim}12$ Gy in youngwoljaerae cultivar.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1401-1405
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• 2012

Aim: To investigate the protective effect of purified fraction 1 polysaccharide extracted from Rheum tanguticum RTP1 on irradiation-induced immune damage in mice. Methods: Kunming mice were randomly divided into five groups: normal group (NC), irradiation control group (IC), RTP1 low dose (200 mg/kg), middle dose (400 mg/kg) and high dose (800 mg/kg) groups. RTP1 was adminstered by the gastric route for 14 d, mice in the NC and IC groups being given by 0.9% sodium chloride solution in the same way. The mice in all groups except NC group were irradiated with 2.0 Gy $^{60}Co{\gamma}$-ray on the fourteenth day. Immune indives of non-specific immune function, cellular immunity and humoral immunity were assessed at the 24th hour after radiation. Results: Compared with the IC group, the spleen index, thymus index, rate of carbon clearance, phagocytic function of macrophages, lymphocyte proliferation, hemolysin value of blood serum and NK activity were increased markedly (P < 0.05 or P < 0.05). Conclusion: RTP1 has an obvious protective effects on damage in ${\gamma}$-ray radiated mice.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.796-801
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• 2010

This study was carried out to establish a system for mutation breeding by irradiation of gamma-ray in $Rosa$ $hybrida$ Hort. The rooted cuttings of two roses, 'Spidella' and 'Cabernet' were irradiated with different gamma-ray doses (0, 30, 50, 70, 90, 110, 130, 150 and 170 Gy) from a $^{60}Co$ source to reveal an optimal dose for induction of mutants. The irradiated plants were planted in a greenhouse, and investigated on the appearance of petal color mutants and shoot growth by gamma ray dose. The 50% lethal doses ($LD_{50}$) of plant were 110 Gy for 'Spidella' and 150 Gy for 'Cabernet', respectively. The 50% decrease dose of shoot length was observed at 70-90 Gy dose for 'Spidella', and 110 Gy dose for 'Cabernet'. Solid, chimeric and mosaic petal mutants with various colors were induced from pink petal of 'Spidella' and red petal of 'Cabernet' when 30-170 Gy dose was irradiated. The mutants obtained from 'Spidella' had white, ivory, pinky ivory, light pink and deep pink petal colors. The mutants obtained from 'Cabernet' had pink, deep pink, purple red (magenta), orange red and purple petal colors. It was suitable to irradiate 70-90 Gy dose for 'Spidella' and 90-110 Gy dose for 'Cabernet' for the induction of various mutants considering plant survival rate, shoot growth and mutant occurrence rate.

• Korean Journal of Medicinal Crop Science
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• v.26 no.2
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• pp.127-133
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• 2018

Background: The demand of recycling renewable agricultural by-products is increasing. Radiation breeding is a method used to improve saccharification efficiency. Thus, we investigated the effect of gamma ray irradiation on the pretreatment and enzymatic hydrolysis of the stalks of Senna tora, an important medicinal plants. Methods and Results: S. tora seeds were irradiated with gamma ray at doses of 100, 200, 300, and 400 Gy. In the pretreated biomass, glucan and lignin content were higher in the M1 ($1^{st}$ generations of irradiation) S. tora stalks than in the M2 ($2^{nd}$ generations of irradiation) stalks, this can be explained by the higher degradation rate in M1. After oxalic acid pretreatment, the concentration of total phenolic compounds (TPCs) in the hydrolysate increased in the gamma ray treated seeds. The highest relative increase rate in crystallinity in the pretreated biomass was observed in M1-400 Gy and M2-100 Gy. The cellulose conversion rate was higher in M1 than in M2, except for 200 Gy. Conclusions: Gamma ray irradiation at an appropriate dose can be used to improve the efficiency of pretreatment and enzymatic hydrolysis, thereby increasing biomass availability.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.109.1-109.1
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• 2003

The aim of this study was to investigate the biological effects of blood and testis by neutron or gamma-ray irradiation in black mouse. Six-week-old C57BL male mice were irradiated with neutron (flux: 1.036739E+09) or Co60 gamma rays(dose rate: lGy/min.) The irradiation method of animal was abdominal irradiation and dose of irradiation was 10 and 20 Gy added with 5 and 15Gy in neutron irradiation.. After that, the mice were sacrificed 3 days later. Blood and testis were taken and then composition of blood in blood cell were investigated. (omitted)

• Nuclear Engineering and Technology
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• v.13 no.3
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• pp.161-167
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• 1981

For determination of mutation frequency induced by chronic irradiation of low dose gamma rays, Tradescarrfia clone 4430 was exposed to Co-60 ${\gamma}$ rays with different exposure rates from 3.6mR/day to 182R/day in or out of the Gamma Field at Kumkok Experiment Farm of KAERI. Somatic mutations based on pink mutant events of the stamen hair cells were clearly observed by the treatment. The pink mutant events were increased proportionally with increasing exposure rates of gamma ray except for relatively high dose rates of 105 R/day and 182 R/day, indicating saturation effect of mutation. The somatic pink mutations could be fairly detectable even in the low dose rate of 3.6mR/day. Therefore, this stamen hair system of Tradescantia clone 4430 seemed to be an reasonable test system for detecting mutability of low level irradiation. These results imply that artificial mutation induction in the fruit and ornamental trees could be expected in the ${\gamma}$-field.

• Journal of radiological science and technology
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• v.30 no.3
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• pp.245-250
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• 2007

This research measured the shielding rates of apron 0.25 and 0.5 mmPb for X-ray energy in diagnosis radiation system and gamma-ray energy of $^{99m}Tc$-MDP and $^{18}F$-FDG. X-ray energies were measured on effective energy of $26.2{\sim}45.6\;keV$ when additional filtering plate of 0, 2 mmAl is used within the range of tube voltage $40{\sim}120\;kVp$, and at this time, apron 0.5 mmPb has shown about 5.5% of increase in its shielding rate over 0.25 mmPb at the highest quality. Besides, the aprons of the two types have shown high shielding rate of over 90% for direct X-ray and spatial dose rate. And, in case 0.25 and 0.5 mmPb aprons were used at 140keV of $^{99m}Tc$-MDP, the shielding effects were between 30 and 53%, and at high energy of 511 keV, $^{18}F$-FDG, the shielding effects of apron, $1.3{\sim}3.6%$, were very small.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.66-69
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• 1999

To investigate the hormetic effect of the low dose ${\gamma}-ray$, soybean(Glycine max L.) seeds of three cultivars (Hwangkeumkong, Bansakong, S900 cv.) were irradiated with the dose of 0.5∼20.0 Gy and cultivated in the experimental field. The hormetic effects of the low dose ${\gamma}-ray$ on the growth of field experiment were different from each cultivar, that is, more effective in the S900 cultivar of black seedcoat color than in the Hwangkeumkong and Bangsakong of yellow ones. The germination rate of S900 cultivar increased about 30% in the 0.5Gy irradiated group compared with that of the control. The plant height of the 4.0Gy irradiated group in both Bangsakong and S900 cultivar increased 15% more than that of the control. Grain yield and the number of pod in 1.0 Gy and 4.0 Gy irradiated group of S900 cultivar and that of 2.0 Gy irradiated group of Hwangkeumkong increased 25 and 35% on the average, respectively.

• Macromolecular Research
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• v.13 no.4
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• pp.327-333
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• 2005

pH-sensitive hydrogels were studied as a drug carrier for the protection of insulin from the acidic environment of the stomach before releasing it in the small intestine. In this study, hydrogels based on poly(ethylene oxide) (PEO) networks grafted with methacrylic acid (MAA) or acrylic acid (AAc) were prepared via a two-step process. PEO hydrogels were prepared by ${\gamma}-ray $ irradiation (radiation dose: 50 kGy, dose rate: 7.66 kGy/h), grafted by either MAA or AAc monomers onto the PEO hydrogels and finally underwent irradiation (radiation dose: 520 kGy, dose rate: 2.15 kGy/h). These grafted hydrogels showed a pH-sensitive swelling behavior. The grafted hydrogels were used as a carrier for the drug delivery systems for the controlled release of insulin. Drug-loaded hydrogels were placed in simulated gastric fluid (SGF, pH 1.2) for 2 hr and then in simulated intestinal fluid (SIF, pH 6.8). The in vitro drug release behaviors of these hydrogels were examined by quantification analysis with a UV-Vis spectrophotometer.

• Nuclear Engineering and Technology
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• v.42 no.3
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• pp.313-318
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• 2010

Alnine pellets were installed in a nuclear power plant for one or two operation cycles and measured by electron spin resonance (ESR) spectrometers for dosimetry. Dose and "x/y ratio", i.e., satellite peak over main center peak ratio, were measured for the returned alanine dosimeters from the nuclear power plant and compared to the values of reference alanine dosimeters exposed only to gamma rays. The variation of the x/y ratio change depended on the population of radicals from each radiation component with different LET. The gamma dose in a mixed radiation field was estimated by an additive gamma ray irradiation experiment and the measured dose rate at specified locations in the containment building.