• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.3
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• pp.43-49
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• 2010

Recently, the use of fumigants for pest control of paper cultural heritages are limited because of the high toxicity of fumigants and the production of environment-harmfully compounds. Therefore, many non-chemical methods have been discussed and experimented. And it is recently focused on gamma radiation, which is one of non-chemical methods, for pest control of paper cultural heritage in Korea. In this paper, we carried out a gamma ray irradiation of papers including Hanji, copy paper, filter paper and then analyzed a physical properties and optical properties of paper sample to estimate the effect of gamma ray irradiation on paper properties. In result, gamma radiation have adverse effect on a physical properties and optical properties of paper, especially Hanji. Therefore, we have to carefully consider about using of gamma ray for pest control of paper cultural heritages.

• The Journal of the Korea Contents Association
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• v.9 no.7
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• pp.211-217
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• 2009

In order to find out the radioprotective effect of algin-oligosaccharide, this study, with a mouse of which whole body irradiated by 3 Gy radiation once, measured nitric oxide. In nitric oxide test for observing the reaction of cell inflammation, nitric oxide showed decreased in the irradiation control group, while 3 day's treatment group with algin-oligosaccharide before or after irradiation indicated higher than the irradiation control group, especially showed big difference in 3 day's treatment group before irradiation (P<0.001). Consequently, this study inquired into the fact that algin-oligosaccharide with superior antioxidant activity performed radiation protection by increasing promotion of nitric oxide generation and confirmed that natural product with less chemical toxicity was able to be applied as radioprotector.

• Polymer(Korea)
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• v.29 no.1
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• pp.91-95
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• 2005

The PVA hydrogels were prepared by the chemical and irradiation method to improve the heat resistance of these hydrogels at the high temperature. The physical properties such as the gel content, the degree of swelling and the gel strength for the synthesized hydrogels were examined. Gel content increased as the chemical reaction time and the irradiation dose increased, and gel content of the hydrogels were higher when the two-steps of chemical and irradiation method were used rather than only the chemical method. Gel strength increased as the chemical reaction time increased, and as the irradiation dose decreased. The hydrogels prepared by the chemical reaction for 5 hours and the two-steps had the heat resistance at the high temperature.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.555-565
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• 2023

Despite many advantages as structural materials, austenitic stainless steels (SSs) have been avoided in many next generation nuclear systems due to poor void swelling resistance. In this paper, we report the results of heavy ion irradiation to the recently developed advanced radiation resistant austenitic SS (ARES-6P) with nanosized NbC precipitates. Heavy ion irradiation was performed at high temperatures (500 ℃ and 575 ℃) to the damage level of ~200 displacement per atom (dpa). The measured void swelling of ARES-6P was 2-3%, which was considerably less compared to commercial 316 SS and comparable to ferritic martensitic steels. In addition, increment of hardness measured by nano-indentation was much smaller for ARES-6P compared to 316 SS. Though some nanosized NbC precipitates were dissociated under relatively high dose rate (~5.0 × 10^-4 dpa/s), sufficient number of NbC precipitates remained to act as sink sites for the point defects, resulting in such superior radiation resistance.

• Radiation Oncology Journal
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• v.2 no.1
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• pp.25-32
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• 1984

The pathological changes of stomach of the rat following 1,000 rad and 1,800 rad single exposure by Cobalt-60 has been made with 50 experimental rats. The dose of 1,000 rad and 1,800 rad single exposure were equivalent of biologic effect of 2,500 rad in 2 1/2 weeks and 6,000 rad in 6 weeks. Following single exposure, the groups of rat were terminated in 1, 2, 4, 8, 12 weeks intervals and the stomach were fixed to formalin solution immediatly after dissection. The pathological changes were as follows : 1. Following 1,000 rad single exposure, the stomach show only mild to moderate submucosal edema in 4,8,12 weeks group. 1 and 2 weeks group show no changes. 2. Following 1,800 rad single exposure, $32\%(8/25)$ of rats were dead by radiation effect and all other groups of stomach revealed variable pathological changes such as submucosal edema, squamous dysplasia, squamous papilloma as well as squamous cell carcinoma. 3. Optimal tolerance dose to the stomach was $4,500\~5,000$rad when irradiation given by supervoltage. The entire stomach was included within the irradiation field, the dose to the stomach should not exceed 6,000 rad. 4. In conclusion, the radiation injury to the stomach were more direct radiation effects to the gastric mucosa rather than secondary changes of radiation injured vessels.

• The Plant Pathology Journal
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• v.31 no.2
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• pp.176-180
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• 2015

Postharvest diseases cause losses in a wide variety of crops around the world. Irradiation, a useful nonchemical approach, has been used as an alternative treatment for fungicide to control plant fungal pathogens. For a preliminary study, ionizing radiations (gamma, X-ray, or e-beam irradiation) were evaluated for their antifungal activity against Botrytis cinerea, Penicillium expansum, and Rhizopus stolonifer through mycelial growth, spore germination, and morphological analysis under various conditions. Different fungi exhibited different radiosensitivity. The inhibition of fungal growth showed in a dose-dependent manner. Three fungal pathogens have greater sensitivity to the e-beam treatment compared to gamma or X-ray irradiations. The inactivation of individual fungal-viability to different irradiations can be considered between 3-4 kGy for B. cinerea and 1-2 kGy for P. expansum and R. stolonifer based on the radiosensitive and radio-resistant species, respectively. These preliminary data will provide critical information to control postharvest diseases through radiation.

• Journal of Plant Biotechnology
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• v.46 no.2
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• pp.88-96
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• 2019

Terpenes constitute a large class of secondary metabolites in plants. The Oryza sativa terpene synthase is a vital gene in plant defense response. In this study, the molecular and physiological functions of Oryza sativa terpene synthase 30 (OsTPS30, LOC_Os08g07080) were investigated after exposure of the seeds and plants to gamma-rays. The OsTPS30 expression was slightly induced at 200 Gray (Gy), but was significantly induced at 400 Gy. The total terpenoid was synthesized more in OsTPS30-overexpressing (OX-OsTPS30) Arabidopsisthaliana plants than in wild-type (WT) plants. The OX-OsTPS30 plants exhibited resistance to gamma-rays, as compared to WT. The OX-OsTPS30 plants had significantly increased height and weight after gamma irradiation. Additionally, the activity of antioxidant enzymes was increased more in OX OsTPS30 plants than in WT plants after gamma irradiation. Furthermore, the OsTPS30-GFP fusion protein was mostly localized in the chloroplast, suggesting that OsTPS30 is putative MEP pathway-related terpene synthase.

• The Journal of Korean Society for Radiation Therapy
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• v.9 no.1
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• pp.87-93
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• 1997

The using of compensator is required to adjust the irregular dose distribution due to irregular thickness of the body in Total Body Irradiation. Aluminuim, copper or lead is generally used as compensator. In our study, we would like to introduce a result of the attenuation and compensation effect of radiation use compensator made by duralumin and its clinical use. The thickness of compensator was calculated by the attenustion of radiation, which was measured by polystyrene phantom and ionization chamber(farmer). The compensation effect of radiation was measured by diode detector. All of conditions were set as in real treatment, and the distanc from source to detector was 446 cm. We also made fixation of device to easily attach the compensator to LINAC. Beam spoiler was menufactured and placed on the patient to irradiate sufficient dose to the skin. diode detector were placed on head, neck, chest, umbilicus. pelvis and knee with each their entranced exit points, and datas of dose distribution were evaluated and compared in each points for eleven patients(Feb. 96-Feb. 97). The attenuation rate of irradiation by duralumin compensator was measured as $1.4\%$ in 2mm thickness. The mean attenuation rate was $1.3\%$ per 2mm as increasing the thickness gradually to 50 mm. By using duralunim compensator, dose distribution in each points of body was measured with ${\pm}2.8\%$ by diode detectior. We could easily calculate the thickness of compensator by measuring the attenuation rate of radiation, remarkably reduce the irragularity of dose distribution duo to the thickness of body and magnify the effect of radiation therapy.

• Entomological Research
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• v.48 no.5
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• pp.331-338
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• 2018

Spotted wing drosophila (SWD) has emerged as a major invasive insect pest of small berry fruits in the Americas and Europe since the late 2000s. Thus, phytosanitary treatment of commodities for export is imperative to prevent the movement of viable SWD to newer areas. In the present study, all developmental stages of SWD were irradiated with different doses of gamma and electron beam radiation to assess developmental inhibition to identify potential quarantine doses of the radiations. Ionizing radiation induced developmental inhibition of all stages of SWD. The effective doses for 99% inhibition ($ED_{99}$) of hatching, pupariation, and adult emergence from irradiated eggs for gamma radiation were 882, 395 and 39 Gy, respectively, compared with 2849, 687, and 41 Gy, respectively, for electron beam radiation. The $ED_{99}$ for inhibition of pupariation and adult emergence in irradiated larvae were 703 and 47 Gy, respectively, for gamma radiation, and 619 and 33 Gy, respectively, for electron beam radiation. Pupal irradiation did not completely inhibit adult emergence, even at 300 Gy. However, irradiation with ${\geq}100Gy$ of puparia induced adult sterility, with no egg production at all. The $ED_{99}$ for inhibition of $F_1$ egg hatchability from adults irradiated with gamma radiation and electron beam radiation was estimated to be 424 and 125 Gy, respectively. The results of the present study suggest that gamma radiation and electron beam radiation are alternatives for phytosanitary treatment. Irradiation with 100 Gy could be suggested as a potential dose for egg, larval, and pupal quarantine treatment of SWD.

• The Journal of Korean Society for Radiation Therapy
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• v.13 no.1
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• pp.91-103
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• 2001

In those patients who underwent radiation therapy with 10 MV X-ray for bone marrow transfer, compared the effect of high dose irradiation on peripheral blood were investigated in randomly selecting 18 patients. thus, changes in the levels of peripheral blood (WBC, Seg. neutrophil, Lymphocyte, RBC, Hemoglobin, Hematocrit ratio, GOT, GPT) were observed for 25 days after irradiation with the peripheral blood levels before irradiation in these patients and in 32 controls. Among changes in peripheral blood, the level of WBC was $8.63\%$ after radiation therapy with as much decrease as $0.22{\times}103{\pm}0.19{\times}103/mm^3$ compared with $2.51{\times}103{\pm}1.29{\times}103/mm^3$ before radiation therapy, and was only $6.35\%$ of $7.17{\times}103/mm^3{\pm}1.46{\times}103/mm^3$ in the controls, showing statistical significance (P<0.01, r2=0.9151). In the morphologic test of WBC, the level of Seg. neutrophil was decreased as much as to $20.53\%$ with $14.17{\pm}21.60\%$ compared with $69.00{\pm}25.60\%$ before irradiation, and decreased down to $24.39\%$ compared with $58.09{\pm}7.62\%$ in the controls (P<0.05, r2=0.6316). The number of lymphocyte increased as much as 3.94 folds at $79.91{\pm}27.30\%$ compared with $20.29{\pm}21.15\%$ before irradiation and was 2.39 times higher than $33.46{\pm}6.79\%$ in the controls (P<0.05, r2=0.7337). Although the change in the number of RBC was little with $3.18{\times}106{\pm}0.41{\times}106/mm^3$ before irradiation and $4.66{\times}106{\pm}0.43{\times}106/mm^3$ in the controls, no statistical significance was present (P>0.05). In addition, The number of hemoglobin was low compared with before irradiation and with the controls, but none showed statistical significance (P>0.05). Similarly, although the hematocrit ratio was low compared with before irradiation and with the controls, no statistical significance was present (P>0.05). In the values of the histologic examinations GOT and GPT, there is statistical significance between those from with before irradiation and with the controls (P<0.05). Thus, among peripheral blood, the number of WBC decreased drastically for a certain period after total body irradiation with high dose radiation, and the levels of Seg. neutriphil and lymphocyte decreased significantly after irradiation in the lymphocyte morphologic test. The results of the present study suggest that the possibility of developing the first to determine initially those patients who might develop radiation acute impairment using the usual peripheral blood test of patients to be exposed to high dose irradiation.