• 제어로봇시스템학회논문지
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• 제17권12호
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• pp.1203-1209
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• 2011

In this paper, the degradation evaluation method of VLC (Visible Light Communication) wireless module after high dose rate gamma-ray irradiation using the thermal infrared camera is proposed. First, the heating characteristics of the active devices embedded in the VLC wireless module during the condition of normal operation is monitored by thermal infrared camera. By the image processing technique, the trends of the intensity of the heat emitted by the active devices are calculated and stored. The feature of the blob area including the area of the active devices in the thermal infrared image is extracted and stored. The feature used in this paper is the mean value of the gray levels in the blob area. The same VLC module has been gamma irradiated at the dose rate of about 4.0 kGy/h during 72 hours up to a total dose of 288 kGy. And then, the heating characteristics of the active devices embedded in the VLC wireless module after high dose gamma ray irradiation is observed by thermal infrared camera. The high dose gamma-ray induced degradation of the active devices embedded in the VLC module was evaluated by comparing the mean value of the blob area to the one of the same blob area of the VLC module before the gamma ray irradiation.

• 방사선산업학회지
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• 제6권3호
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• pp.217-221
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• 2012

The purpose of this study is to reduce the immune toxicity of lipopolysaccharide (LPS) by gamma irradiation. LPS was gamma-irradiated at the various doses of 20, 100 and 200 kGy and then evaluated on the immune toxicity through the cell proliferation, nitricoxide production and cytokine release. Cell proliferation significantly decreased in the intact LPS treated groups, whereas gamma-irradiated LPS treated group were not reduced the cell proliferation. Similarly, the production of nitric oxide and cytokine showed the high levels in the intact LPS treated group. However, gamma-irradiated LPS treated group remarkably decreased the production of nitric oxide and cytokine in dose-dependent manner. Therefore, gamma irradiation may effective method to reduce the immune toxicity of LPS.

• 방사선산업학회지
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• 제5권2호
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• pp.169-173
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• 2011

This study investigated the effect of gamma irradiation on immune enhancing activity of Chaga mushroom extract (CME). CME was prepared by hot water extraction at $70^{\circ}C$ for 4 hours and lyophilized. Lyophilized CME powder was dissolved with deionized water at $10mg\;ml^{-1}$ and then irradiated at the doses of 10, 30 and 50 kGy by cobalt 60 gamma irradiator. The gamma-irradiated and non-irradiated CME were treated into the splenocyte separated from mouse. Cell proliferation and cytokine production of the immune cells were increased by gamma-irradiated CME and these increases were more prominent when CME was irradiated at higher doses. Therefore, it is considered that gamma irradiation can be an effective method for improvement of the immunomodulating activity Chaga mushroom extract.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1993-1996
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• 2010

Silver nanoparticles has been prepared by the $\gamma$-irradiation and in situ reduction methods. Based on the Raman spectra, TEM images, X-ray Diffraction (XRD) patterns and UV-vis spectra, the in situ reduction method is more stable and the average size of the silver nanoparticles is also smaller than by the $\gamma$-irradiation reduction method. It is identified that the silver ions interacting with nonbonding electrons of oxygen atom in the carbonyl group of polyvinylpyrrolidone (PVP) by the in situ reduction method. It is also found advantages of the in situ reduction method including no additional reducing agents, without $\gamma$-irradiations treatment and the room temperature treatment suitability.

• Parasites, Hosts and Diseases
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• 제49권4호
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• pp.423-426
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• 2011

In the genus Cryptosporidium, there are more than 14 species with different sizes and habitats, as well as different hosts. Among these, C. parvum and C. hominis are known to be human pathogens. As C. parvum can survive exposure to harsh environmental conditions, including various disinfectants or high doses of radiation, it is considered to be an important environmental pathogen that may be a threat to human health. However, the resistance of other Cryptosporidium species to various environmental conditions is unknown. In this study, resistance against ${\gamma}$-irradiation was compared between C. parvum and C. muris using in vivo infection in mice. The capability of C. muris to infect mice could be eliminated with 1,000 Gy of ${\gamma}$-irradiation, while C. parvum remained infective in mice after up to 1,000 Gy of ${\gamma}$-irradiation, although the peak number of oocysts per gram of feces decreased to 16% that of non-irradiated oocysts. The difference in radioresistance between these 2 Cryptosporidium species should be investigated by further studies.

• 한국식품위생안전성학회지
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• 제6권3호
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• pp.157-163
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• 1991

염장미역은 염농도 감소와 저장조건의 완화를 위한 연구의 일환으로서 2~4kGy의 감마선을 조사하고 ${30{\pm}2^{\circ}C와\;10{\pm}1^{\circ}C$에 저장하면서 미생물적, 관능적 품질을 평가한 결과는 다음과 같다. 염장미역의 변질에 관련된 원인 미생물은 호염성 세균과 효모로 확인되었으며, 2~4kGy의 감마선 조사는 초기의 미생물 수준을 1~2 log orders 감소시켰으나 저장 기간 중 증식에는 뚜렷한 영향이 없었다. 관능적 품질에서도 감마선 조사에 의한 미역조직의 연화현상으로 비조사군보다 낮은 기호도를 나타내어 저장 중 품질 안정성 향상에 별 효과가 없는 것으로 나타났다.

• 한국식품영양과학회지
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• 제28권1호
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• pp.40-46
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• 1999

Microbiological quality of commercial white ginseng was examined, together with investigation on its water absorption pattern and radiosensitivity of molds isolated from the samples. Comparative effects of phosphine fumigation and gamma irradiation on microbial control and disinfestation of the samples packed in a commercial laminated film and stored for six months at ambient(20oC, 70% RH) and accelerated(40oC, 90% RH) conditions were studied. Commercial white ginseng was contaminated with coliforms by 103~104CFU/g and molds by 102~104CFU/g and thus decontamination process was required for hygienic quality and storage stability. Phosphine fumigation showed no sterilizing effects on microbes contaminated, while gamma irradiation at around 5kGy was effective for decontaminating microorganisms, showing D10 values of 0.48~0.60kGy for isolated molds. Even though the storage insects, Plodia interpuctella Hubner and Lasioderma serricorne(cigarette beetle) were easily destroyed by phosphine fumigation, gamma irradiation less than 5kGy was found effective for both purposes to improve biological quality of stored white ginseng, thereby extending the storage life of packed samples resulting from increased critical moisture content by about 1%(Aw 0.76).

• 생약학회지
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• 제36권3호통권142호
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• pp.220-223
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• 2005

The purposes of this study was to develop the best one among the methods using dry heat, gamma irradiation and alcohol gas, to sterilize Scutellariae Radix selected based on high frequency of circulation between merchants and high susceptibility to microbial contamination, through comparing these methods in terms of the followings; ⅰ) the efficacy of sterilization in comparison with cost, and ⅱ)the alteration of chemical components of these herbal medicines. The results of this study will be taken advantage of establishment of the maximum limit of microorganism contaminated in herbal medicines. From the results of this study we conclude the followings: ⅰ) The sterilizing method using dry heat may be inappropriate, because it seriously changed their color and morphology which is an essential criterion to estimate a measure of quality between merchants and consumers, although it effectively got rid of contaminated microorganism and did not alter major components, baicalin; ⅱ) The sterilizing method using gamma irradiation may be appropriate, because it showed a strong sterilizing effect, and no alteration of chemical components, color and morphology; ⅲ)The sterilizing method using alcohol gas may also be appropriate, because it had a similar effects as in the case of gamma irradiation. Collectively, we suggest that appropriate sterilizing methods to guarantee the microbial quality of this herbal medicine may be those using gamma irradiation and alcohol gas.

• 한국식품과학회지
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• 제6권1호
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• pp.36-41
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• 1974

한천 원조(原藻)로서 완도(莞島), 여수(麗水), 남해(南海)지역에서 수집한 꼬시레기 및 우무가사리와 마닐라에서 수입한 알카리 처리된 꼬시레기, 그리고 알진산원조로서 제주(濟州)지역에서 수집한 감태에서 한천 또는 알진산의 추출수율을 증대시키기 위한 실험을 수행하여 다음과 같은 결과를 얻었다. 국내산 원조(原藻)로 부터의 한천 추출에 있어서 꼬시레기는 갈마선(線) 처리효과가 없었으나 우무가사리는 8-10%의 수율증가를 보였다. 마닐라산 원조(原藻)에서는 1.5 Mrad의 감마선 조사(照射)에 의하여 25-30%의 한천수율이 증가하였고 이와 같이 제조된 한천은 이화학적 특성이 대조구와 비슷하였다. 한국산 감태로부터의 알진산 추출에 있어서 0.3 Mrad의 감마선 조사(照射)는 6%의 수율증가를 보였다.

• 한국식품과학회지
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• 제30권5호
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• pp.1179-1183
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• 1998

감마선 조사$(1{\sim}5\;kGy)$된 우육(사태부위; M.Semitendinosus)의 저장 안전성을 살펴보기 위하여 실온$(25^{\circ}C)$과 냉장$(4^{\circ}C)$온도에서 10일 동안 포장방법(함기, 진공)별로 저장하면서 과산화물가, TBA가, 휘발성 염기태 질소함량을 측정하여 다음의 결과를 얻었다. 총지방 함량은 $4.4{\sim}4.7%$로 감마선 조사에 따른 변화는 없었고, 과산화물가와 TBA가는 모든 시험군에서 저장기간이 경과됨에 따라 증가되었으며, 실온저장이 냉장보다 그리고 함기포장이 진공포장보다 높은 산패도를 보였고, 감마선 조사에 의한 영향은 선량이 높아짐에 따라 증가되었다. 휘발성 염기태질소 함량은 감마선 조사직후에는 비조사군과 조사군간에 차이가 없었으나, 저장기간이 경과함에 따라 진공포장하여 $3{\sim}5\;kGy$ 조사후 냉장한 시험군이 가장 낮은 함량을 나타내었다.