• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.297-303
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• 2000

Gamma irradiation at 20 kGy was applied to Kanjang (soy sauce), Doenjang (soybean paste), Kochujang (hot pepper pasts) and Chungkukjang for their possible genotoxicity. The genotoxicity of 20 kGy-irradiated samples was evaluated by Salmonella typhimurium reversion assay. The Salmonella tester strains included TA98, TA100, TA1535 and TA1537 in the absence and presence of an exogenous metabolizing system (59 mix). All samples were negative in the bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537. The results indicated that 20 kGy of gamma irradiation on water-soluble fraction of Kanjang, Doenjang, Kochujang and Chungkukjang were not shown mutagenicity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1264-1270
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• 2008

In order to evaluate their possible subacute toxicity, the male and female of SD rats were given to 30 kGy irradiated cereal powders for three months. During the experimental periods, appearance, behavior, mortality, body weight, organ weight, and food consumption of rats fed the 30 kGy cereal powders were not affected compared to the non-irradiated control. In urine analysis, histopathological examination, hematological as well as in serum biochemical findings, no significant differences were found between the rats administered with non-irradiated control and 30 kGy cereal powders for three months. These results indicate that cereal powders irradiated at 30 kGy did not show any toxic effects under these experimental conditions.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.173-178
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• 1995

A quantitative assay was performed on the effects of gamma-irradiation (30- 300 Gy) on intracellular proliferation of Toxoplosmn gonnii RH tachyzoites in human leukemic HL-60 cells and murine peritoneal macrophages by means of 3H-uracil uptake assay. Infected non-irradiation group (NI) and uninfected group (incubating only host cells) were prepared. The 3H-uracil uptake by tachyzoites of NI group 12-24 hrs after infection was 2,190-4,787 counts per minute for macrophages and 2,967-8,254 for HL-60 cells, whereas the irradiated tachyzoites revealed only 381-703 (100 Gy) and 218-408 (300 Gy) for macrophages, and 1,911-2,618 (30 Gy), 1,253-1,384 (70 Gyl, 1,013-1,090 (100 Gyl, and 483-588 (300 Gy) for HL-60 cells. The proliferation inhibition rate was similar in macrophages and HL-60 cells, for example, 89-94% and 80-94% respectively by 300 Gy, 12-24 hrs after infection. It is concluded that RH tachyzoites of T gondii are severely affected by gamma-irradiation in their capability of Intracellular proliferation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.6
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• pp.1035-1041
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• 2000

Gamma irradiation was used to improve sanitation and quality of salted and fermented anchovy sauce. For commercial production, comparison with currently using sterilization methods, such as micro-filtration and heat treatment were also conducted. Control was prepared without irradiation and sterilization process. Microbiological, physiochemical, and sensory qualities were analyzed to observe the Quality changes during the storage. Irradiation at 5 kGy or above and micro-filtration process completely eliminated microorganisms detected in this study As irradiation dose increased, the color appeared brighter and irradiation at 5 kGy or above showed similar color L-value to that of sample treated with microfiltration. The color L, a, b-value of heat-treated sample always showed lower. The pH, salinity, and viscosity were sustained during storage. From the results of sensory evaluation, the samples treated with gamma irradiation and microfiltration obtained better scores than control or heat-sterilized. Gamma irradiation to salted and fermented anchovy sauce presented the best quality products among different sterilizing methods, especially at 5 kGy dose. Therefore, gamma irradiation can be successfully applied to commercial large scale production as a new sanitation technology with improved quality.

• Korean Journal of Veterinary Research
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• v.33 no.4
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• pp.649-655
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• 1993

A series of experiments on the effects of ${\gamma}-irradiation$ was performed to reveal the pathogenicity of ${\gamma}-irradiated$ oocysts of E tenella from Cobalt-60 and its progeny. The SPF chickens were inoculated with differnt doses of radiation and inoculum. The level of 100 Gy ${\gamma}-irradiation$ from $^{60}Co$ and the level of inoculum with $1{\times}10^4$ oocysts were recognized more pathogenic than those of the other groups by comparison of body weight gains, blood in feces and lesion scores. The signs of blood in feces, lesion score and the number of excreted oocysts in the feces were revealed as the lowest in the group of the ${\gamma}-irradiated$ oocysts, the average in the group of the 1st and the 3rd progeny, and the highest in the group of non-irradiated oocysts of E $tenell\grave{a}$. The body weight gain of the group immunized with ${\gamma}-irradiated$ oocysts of E tenella was higher than those of the non-irradiated, the 1st and 3rd progeny groups. The body weight gain of the groups immunized with the 1st and the 3rd progeny of E tenella were higher than that of the non-irradiated group. The feed conversion ration of the group immunized with ${\gamma}-irradiated$ oocysts of E tenella was lower than those of the non-irradiated, the 1st and the 3rd progeny groups. The feed conversion ratios of the group immunized with the 1st and 3rd progeny of ${\gamma}-irradiated$ oocysts were lower than that of the group infected with non-irradiated E tenella. The anticoccidial index(ACI 190.6) in the chickens immunized with the ${\gamma}-irradiated$ oocysts of E tenella and those(ACI 142.8 and 107.4) of the 1st and the 3rd progeny groups were higher than that (ACT 87.4) of the group infected with non-irradiated E tenella. It was thought that the pathogenicity of ${\gamma}-irradiated$ E tenella would be recovered according to increase the number of generation passaged in chicken.

• Korean Journal of Materials Research
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• v.6 no.9
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• pp.905-918
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• 1996

초전도 마그네트 구조용 부재로 최근 개발된 오스테나이트계 스테인레스강 JN1 모재, GTA 용접부 및 열처리재에 대한 기계적 성질을 조사하기 위해 실온(293K)에서 극저온(4K)까지의 온도에서 소형펀치(Small Punch)시험을 실시하였다. GTA 용접부의 용융선 근방의 극저온 기계적 성질은 모재와 용접금속에 비해 크게 저하하였다. 4K에서 실험된 용융선 시험편으로 얻어진 하중-변위곡선상에서 부하의 초기 단계에 보통의 서레이션과 다른 pop-in이 관찰되었고, 이때 시험편 표면의 용융선 근처에서 약 0.1-1mm 정도의 크랙이 발생하였다. 열처리재의 기계적 성질은 열처리 시간과 온도의 증가 또는 시험온도의 저하에 따라 크게 저하되었다. 위의 결과에 기초하여 본 연구에서 실시한 소형 시험편을 사용하는 SP 시험법은 극저온에서 JN1 강의 모재와 열처리재뿐 만 아니라 GTA 용접부의 기계적 성질을 평가할 수 있는 유용한 시험법이었다.

• Journal of radiological science and technology
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• v.27 no.4
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• pp.37-41
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• 2004

Purpose : Raise ability cultivation in presence at a sicked business by performance management estimation of device through measurement. Also Learn a technology that measure exact tube voltage, exposure time, output dose. And it is to grasp photofluorography X-ray generator existing circumstances using at hospital. Material & Method : Investigated Photofluorography X-ray generator(inside, outside each 10) of 10 university hospitals using tube voltage, exposure time, output dose measuring instrument. Result : Photofluorography device that tube voltage correctness is incongruent by examination PAE decision came out 3, and at exposure time correctness examination 2 incongruent, Also 3 that calculate coefficient of variation about exposure in repeatability examination of exposure were incongruent. Inappropriate photofluorography device is 5 outside hospital(mobile unit) and the thing in hospital was 3 in 3 kind of efficiency test. It appeared high that photofluorography device outside hospital is more incongruent than thing in hospital. Conclusion : May ready situation that can offer patient medical service of good quality by radiation exposure reduction, image quality administration, retake decrease etc. by keeping performance of Photofluorography device. Therefore, is considered that need on-time efficiency test.

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.24-24
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• 1999

• Proceedings of the Korean Nuclear Society Conference
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• 2002.05a
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• pp.237.2-237
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• 2002

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1534-1539
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• 2012

This study was conducted to evaluate the possible subacute toxicity of gamma-irradiated Tarakjuk. Tarakjuk was irradiated at a dose of 30 kGy at room temperature. For the animal study, AIN-93G as a control diet and 30 kGy irradiated and non-irradiated Tarakjuk diets were administered to male and female ICR mice (10 mice per group) for 3 months. During the experimental period, the group fed 30 kGy irradiated Tarakjuk did not show any changes in appearance, behavior, mortality, body weight, organ weight, or food consumption compared to control. Further, all biochemical parameters were in normal ranges. In the histopathological examination of liver and kidney tissues of ICR mice, there were no significant differences between the control and 30 kGy irradiated Tarakjuk groups. These results indicate that Tarakjuk irradiated at 30 kGy did not cause any toxic effects under these experimental conditions.