• 제목/요약/키워드: gamma-irradiation

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Cobalt-60 gamma 선(線) 조사(照射)가 가토(家兎)의 성장(成長)에 미치는 영향(影響) (Effects of Cobalt-60 γ Irradiation on the Growth of Rabbits)

  • 성재기
    • 대한수의학회지
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    • 제12권1호
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    • pp.1-5
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    • 1972
  • In oder to investigate the effects of cobalt-60 gamma ray irradiation on the body gains of rabbits aging approximately 50-day-old rabbits were subjected to single whole-body gamma irradiation externally. The results obtained were as follows: 1. There were significant differences of the body gains between control and treated groups except the 100 rads gamma-rays exposure group. 2. There were no differences in body gains between male and female rabbits. 3. Generally, the relation between gamma irradiated doses and the growth rates of rabbits were inversly proportional. 4. The $LD_{50}$ of the rabbits was 600 rads in case of single external whole-body gamma irradiation.

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Comparison of Effects of Ultraviolet and $^{60}$ Co Gamma Ray Irradiation on Nylon 6 Mono-filaments

  • Ohtsuka, Mika;Suzuki, Yoshino;Sakai, Tetsuya;Netravali, Anil N.
    • Fibers and Polymers
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    • 제5권3호
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    • pp.225-229
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    • 2004
  • The effect of UV and $^60{Co}$ gamma radiations on the physical and mechanical properties of nylon 6 mono-filaments with different draw ratios has been studied. Specimens were exposed to either up to 25 Mrad of gamma or up to 168 hrs of intense UV irradiation. The results show that nylon mono-filaments exposed to gamma rays, with much higher quantum energy than UV, undergo a larger extent of molecular chain scission. Higher irradiation dose also results in the production of insoluble, macroscopic three-dimensional cross-linked network structure. The amorphous regions with a lower density of cohesive energy (lower molecular orientation) show a higher extent of cross linking reaction whereas amorphous regions with a higher density of cohesive energy (higher orientation) show higher extent of chain scission reaction, irrespective of UV ray or gamma ray irradiation.

Development of a Stereotactic Device for Gamma Knife Irradiation of Small Animals

  • Chung, Hyun-Tai;Chung, Young-Seob;Kim, Dong-Gyu;Paek, Sun-Ha;Cho, Keun-Tae
    • Journal of Korean Neurosurgical Society
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    • 제43권1호
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    • pp.26-30
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    • 2008
  • Objective : The authors developed a stereotactic device for irradiation of small animals with Leksell Gamma Knife Model C. Development and verification procedures were described in this article. Methods : The device was designed to satisfy three requirements. The mechanical accuracy in positioning was to be managed within 0.5 mm. The strength of the device and structure were to be compromised to provide enough strength to hold a small animal during irradiation and to interfere the gamma ray beam as little as possible. The device was to be used in combination with the Leksell G-$frame^{(R)}$ and $KOPF^{(R)}$ rat adaptor. The irradiation point was determined by separate imaging sequences such as plain X-ray images. Results : The absolute dose rate with the device in a Leksell Gamma Knife was 3.7% less than the value calculated from Leksell Gamma $Plan^{(R)}$. The dose distributions measured with $GAFCHROMIC^{(R)}$ MD-55 film corresponded to those of Leksell Gamma $Plan^{(R)}$ within acceptable range. The device was used in a series of rat experiments with a 4 mm helmet of Leksell Gamma Knife. Conclusion : A stereotactic device for irradiation of small animals with Leksell Gamma Knife Model C has been developed so that it fulfilled above requirements. Absorbed dose and dose distribution at the center of a Gamma Knife helmet are in acceptable ranges. The device provides enough accuracy for stereotactic irradiation with acceptable practicality.

감마선 완·급조사에 따른 애기장대의 유전적 유연관계 분석 (Genetic Variation Analysis of Arabidopsis (Arabidopsis thaliana L.) Plants Induced by Acute and Chronic Gamma Irradiation)

  • 고은정;김진백;하보근;김상훈;강시용;김동섭
    • 방사선산업학회지
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    • 제5권4호
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    • pp.347-352
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    • 2011
  • In order to identify the genetic relationship analysis by acute and chronic gamma irradiation, Arabidopsis (Arabidopsis thaliana L.) were irradiated with 200 Gy of gamma-rays using gamma-irradiator (3,000 Ci; Nordion, Canada) and gamma-phytotron (400 Ci; Nordion, Canada) for acute and chronic irradiation, respectively. Genetic relationship among two acute gamma-irradiated plants (A1 and A24) and three chronic gamma-irradiated plants (C1W, C2W, C3W) were analyzed using the amplified fragment length polymorphism (AFLP) technique compared with each non-irradiated plant. A total of 28 EcoRI and MseI primer combinations were used to screen 8 treatments by the ABI3130 capillary electrophoresis system. Amplified products by 28 primer sets showed 1,679 bands with an average of 51 bands per primer combination. Out of the total bands scored, 1,164 fragments were polymorphic bands, with different alleles existing among the treatments. The cluster analysis was performed using the UPGMA (Unweighted Pair Group Method using Arithmetic) in the computer program NTSYS-pc. In clustery analysis, acute gamma-irradiation showed higher genetic variation compared with chronic gamma-irradiation.

감마선 조사와 로즈마리 추출분말 병용처리가 즉석 햄버거 스테이크에 미치는 영향. II. 품질 개선 효과 (Effects of Combined Treatment of Gamma Irradiation and Addition of Rosemary Extract Powder on Ready-to-Eat Hamburger Steaks: II. Improvement in Quality)

  • 박경숙;김종군;이주운;오상희;이유석;김장호;김재훈;김왕근;변명우
    • 한국식품영양과학회지
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    • 제33권4호
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    • pp.694-699
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    • 2004
  • 본 연구는 즉석 햄버거 스테이크의 감마선 조사(5, 10 및 20 k㏉) 또는 냉장저장에 의한 품질변화를 최소화하기 위해 로즈마리 추출분말(200, 500 ppm)을 병용 처리하여 지질 산화 및 색도 측정과 관능평가를 통해 그 효과를 평가하였다. 조사직후 조사구의 TBA값은 Control>Rosemary 200>BHA>Rosemary 500 순으로 나타났다. 감마선 조사에 의해 햄버거 스테이크의 지질 산화가 증가되고 관능적 품질은 감소되었으나, 로즈마리 추출분말을 첨가하였을 때 지질 산화가 억제되고 저장 중 관능적 특성이 향상되었다. 감마선 조사에 의해 즉석 햄버거 스테이크의 경도는 감소되었고, 적색도(a value)는 증가되었으나, 항산화제 첨가에 의한 영향은 없었다.

Improved Detection of ${\gamma}-Irradiated$ Vibrio vulnificus after Heat and Cold Shock Treatment by Using Ethidium Monoazide Real-time PCR

  • Lee, Jung-Lim;Levin, Robert E.
    • Food Science and Biotechnology
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    • 제18권3호
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    • pp.788-792
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    • 2009
  • Gamma $({\gamma})-irradiation$ can be used to control pathogens such as Vibrio vulnificus in seafood. The effects of irradiation on microbial cell populations (%) have been studied in order to develop detection methods for irradiated foods. The method used in this study was ethidium bromide monoazide (EMA) real-time polymerase chain reaction (PCR), using V. vulnificus specific primer, EMA, and $SYBR^{(R)}$ Green to discriminate between ${\gamma}-irradiated$ and non-irradiated cells. Confocal microscope examination showed that ${\gamma}-irradiation$ damaged portions of the cell membrane, allowing EMA to penetrate cells of irradidated V. vulnificus. ${\gamma}-Irradiation$ at 1.08 KGy resulted in log reduction ($-1.15{\pm}0.13$ log reduction) in genomic targets derived from EMA real-time PCR. The combination cold/heat shock resulted in the highest ($-1.74{\pm}0.1$ log reduction) discrimination of dead irradiated V. vulnificus by EMA real-time PCR.

방사선 조사한 쌀가루로 만든 죽의 이화학적 특성 (Effects of Gamma Irradiation on the Physicochemical Properties of Rice Flour Porridge)

  • 양윤형;김민희;권오윤;이근종;박수천;이주운;변명우;김미리
    • 한국식품조리과학회지
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    • 제23권6호
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    • pp.961-967
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    • 2007
  • The aim of this present study was to evaluate the effects of gamma-irradiation on the microbial and physicochemical characteristics of the rice flour porridge. The viscosity of the gamma-irradiated rice flour porridge was decreased as compared to that of the control. The soluble solid and reducing sugar content of the rice flour porridge was increased according to the gamma irradiation dose, while the blue value was decreased. From the results of a DSC curve, it was suggested that gamma irradiation delayed the retrogradation of the cooked rice flour porridge. The sensory score for overall acceptance and the chewing times for swallowing of the porridge, decreased with gamma irradiation doses above 3 kGy. Based on these results gamma irradiation may significantly enhance the swallowability of rice porridge, especially for elderly or infant subjects who have decreased mastication. However, more research is needed to improve the sensory qualities for the industrial application.

$^{60}Co$ 감마선조사가 닭의 정소에 미치는 영향에 관한 연구 (Morphological Study on the Effects of $^{60}Co$ ${\gamma}-irradiation$ on the Testis in the Chicken)

  • 이동명
    • 대한방사선기술학회지:방사선기술과학
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    • 제13권2호
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    • pp.51-51
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    • 1990
  • This study was undertaken to observe the effects of $^{60}Co\;{\gamma}-irradiation$ on the cell of spermatogenic epithelium in the testis of the chicken. 16-week-old chicken were provided as an experimental group and compared with control group. The experimental group was divided into a single irradiation (800, 1000, 1200 rads) and into three partial irradiation group (800/3, 1000/3, 1200/3 rads). The morphological changes of epithelial cell of the testis were observed by means of hematoxyline and eosin stain. Microstructure of spermatocyte and sperm was observed by means of semithin section of electron microscopic specimen. The results obstained are summerized as follows. 1. Spermatogonia and sertoli cells were found to be isolated from the basal membrane of seminiferous tubules as dose of $^{60}Co\;{\gamma}-irradiation$ was increased. 2. Spermatocytes of pachytene stage were seperated from the cytotplasmic process of sertoil cell in case of 1000 rads of $^{60}Co\;{\gamma}-irradiation$. 3. Normal arrangement of the cell of spermatogenic epithelium was found in control group and only the partial irradiation group of 800 rads. Vaculation in the seminiferous was pronounced in case of a single irradiation group of 800 rads, but the irradiation group of 1000 rads and 1200 rads were found to be damaged severely in both a single and a partial dose.

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감마선 조사가 쇠고기의 연도개선에 미치는 효과 (Effect of Gamma Irradiation on the Improvement of Beef Tenderness)

  • 육홍선;이주운;이경행;김덕진;신현길;변명우
    • 한국식품과학회지
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    • 제31권4호
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    • pp.1005-1010
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    • 1999
  • 감마선 조사가 쇠고기의 연도개선에 미치는 효과를 조사하기 위하여 도축 직후 쇠고기에 감마선을 조사시켜 전단력의 변화 및 근육의 미세구조를 관찰하였다. 감마선이 조사된 쇠고기는 최고 전단력치에 도달하는 시간이 감마선 조사선량이 증가함에 따라 단축되었다. 감마선 조사가 근육의 초미세구조에 작용하여 근절의 단축을 지연시켰고, Z-line의 수축을 유도하였다. 또한 감마선이 조사된 쇠고기에서 근속과 perimysium의 파괴는 감마선 비조사구에 비해 더 빨리 진행되는 것이 관찰되었다. 결론적으로 감마선 조사는 쇠고기의 사후경직에 도달하는 시간을 단축시키고, 연도개선 효과에 유효한 것으로 사료된다.

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