• Title/Summary/Keyword: Radiological Effects

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The Implementation of Testing Board forSingle Event Upsets

  • Lho, Young-Hwan;Kim, Ki-Yup
    • International Journal of Aeronautical and Space Sciences
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    • v.5 no.2
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    • pp.28-34
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    • 2004
  • One of the major problem encountered in nuclear plants and satellites design isEMI (Electro-Magnetic Interference) and EMC (Electro-Magnetic Compatibility).Here, our focus is to implement the test board for checking SEU (Single EventUpsets); the effects of protons on the electronic system. The SEU results from thelevel change of stored information due to photon radiation and temperature in thespace environment. The impact of SEU on PLD (Programmable Logic Devices)technology is most apparent in ROM/SRAM/DRAM devices wherein the state ofstorage cell can be upset. In this paper, a simple and powerful test techniques issuggested, and the results are presented for the analysis and future reference. In ourexperiment, the proton radiation facilitv (having the energy of 50 MeV with a beamcurrent of 60 uA of cyclotron) available at KIRAMS (Korea Institute of RadiologicalMedical Sciences) has been applied on a commercially available SRAM manufacturedby Hynix Semiconductor Company.

Evaluation of micronucleus frequency in cytokinesis-blockedlymphocytes of cattle in the vicinity of Uljin nuclear power station (세포질 분열 차단 림프구를 이용한 울진원자력발전소 주변 소의 미소핵 발생 평가)

  • Kim, Se-ra;Kang, Chang-mo;Kim, Sung-ho
    • Korean Journal of Veterinary Research
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    • v.44 no.3
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    • pp.343-348
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    • 2004
  • Cytogenetic and hematological analysis was performed in peripheral blood of cattle in the vicinity of Uljin nuclear power station and control area. The frequency of micronuclei(MN) in peripheral blood lymphocytes from cattle was used as a biomarker of radiobiological effects resulting from exposure to environmental radiation. An estimated dose of radiation was calculated by a best fitting linear-quadratic model based on the radiation-induced MN formation from the bovine lymphocytes exposed in vitro to radiation over the range from 0 Gy to 4 Gy. MN ratio in lymphocytes of cattle from Uljin nuclear power station and control area were 8.90/1,000 and 9.60/1,000, respectively. There were no significant differences in MN frequencies and hematological values in cattle between Uljin and control area.

Uncertainty and Sensitivity Analysis on A Biosphere Model

  • Park, Wan-Sou;Kim, Tae-Woon;Lee, Kun-Jai
    • Journal of Radiation Protection and Research
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    • v.15 no.2
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    • pp.101-112
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    • 1990
  • For the performance assessment of the radioactive waste disposal system (repository), a biosphere model is suggested. This biosphere model is intended to calculate the annual doses to man caused by the contaminated river water for eight pathways and four radionuclides. This model can also be applied to assess the radiological effects of contaminated well water. To account for the uncertainties on the model parameter values, parameter distributions are assigned to these model parameters. Then, Monte Carlo simulation method with Latin Hypercube sampling technique is used. Also, sensitivity analysis is performed by using the Spearman rank correlation coefficients. It is found that these methods are a very useful tool to treat uncertainties and sensitivities on the model parameter values and to analyze the biosphere model. A conversion factor is proposed to calculate the annual dose rate to humans arising from a unit radionuclide concentration in river water. This conversion factor allows for the substitution of the biosphere model in a probabilistic performance assessment computer code by one single variable.

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C2-phytoceramide and Dimethylphytosphingosine induces cell death and apoptosis in human breast cancer cells, MDA-MB-231

  • Kim, Yun-Wha;Jeon, Soo-Jin;Kim, Ki-Sung;Han, Young-Soo;Song, Jie-Young;Park, Chang-Seo;Jung, In-Sung;Hong, Sung-Hee;Yun, Yeon-Sook
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.228.1-228.1
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    • 2003
  • Sphingolipid metabolites have been implicated as an important component of cell signalling, such as cell proliferation, differentiation and apoptosis. But the roles of phytoceramide and its deraivatives are very poorly understood. even though they are abundant in plants, yeasts and animals including humans. We investigated the effects of N-acetyl-C2-phytosphingosine(NAPS) and the analogue of N.N-dimethylsphingosine(DMS), N,N-dimethylphytosphytosphingosine(DMPS), on cell growth inhibition and apoptosis. (omitted)

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Fuzzy FMECA analysis of radioactive gas recovery system in the SPES experimental facility

  • Buffa, P.;Giardina, M.;Prete, G.;De Ruvo, L.
    • Nuclear Engineering and Technology
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    • v.53 no.5
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    • pp.1464-1478
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    • 2021
  • Selective Production of Exotic Species is an innovative plant for advanced nuclear physic studies. A radioactive beam, generated by using an UCx target-ion source system, is ionized, selected and accelerated for experimental objects. Very high vacuum conditions and appropriate safety systems to storage exhaust gases are required to avoid radiological risk for operators and people. In this paper, Failure Mode, Effects, and Criticality Analysis of a preliminary design of high activity gas recovery system is performed by using a modified Fuzzy Risk Priority Number to rank the most critical components in terms of failures and human errors. Comparisons between fuzzy approach and classic application allow to show that Fuzzy Risk Priority Number is able to enhance the focus of risk assessments and to improve the safety of complex and innovative systems such as those under consideration.

Recent Progress in Alpha-emitting Radiopharmaceutical Development for Clinical Application

  • Choong Mo Kang;Yearn Seong Choe
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.8 no.2
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    • pp.157-166
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    • 2022
  • Targeted alpha therapy began to be applied to the treatment of late-stage cancer patients because of its dramatic therapeutic efficacy in patients who have no responses with beta-emitting radiopharmaceuticals. However, its strong cytotoxicity may cause side effects due to undesirable uptake in non-target tissues. In order to use alpha-emitting radiopharmaceuticals for early-stage patients as well as late-stage cancer patients, therefore, modifications on their chemical structures are required. In this review, the recent progress in the development of alpha-emitting radiopharmaceuticals is discussed.

Comparison of Beam Transfer Methods between Tomo Therapy and Proton Therapy for Prostate Cancer Radiation Therapy (전립선암 방사선 치료 시 토모치료와 양성자치료 빔 전달방식 비교)

  • Park, Jung Min;Ko, Eun Seo;Lee, Jin Hee;Kim, Jin Won;Yang, Jin Ho;Kwon, Kyung Tae
    • The Journal of Korean Society for Radiation Therapy
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    • v.31 no.2
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    • pp.75-81
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    • 2019
  • Purpose: Tomo therapy and Proton therapy treatment plans for the treatment of prostate cancer patients were established, and the characteristics of dose distribution according to beam delivery method using Tomo therapy IMRT method and Proton therapy PBS method to compare and analyze the treatment effect were sought. Materials and Methods: Tomo IMRT treatment plan and Proton PBS treatment plan were established using the Hi.art planning station 5.1.1.6 of Tomo therapy and Eclipse 13.7 of VARIAN for three prostate cancer patients who were treated with radiotherapy only for radical purposes without surgery. For the evaluation of two treatment plans, the average dose (Dmean) and maximum dose (Dmax) of PGTV were calculated from dose volume histogram (DVH) to confirm the coverage and calculate CI and HI. In OAR evaluation, the dose received from the rectal volume 25% and the dose received from the bladder were evaluated to compare the normal long-term protection effect. Results: The mean maximum doses of the three patients were 71.4Gy, 75.3Gy and the mean doses were 70.4Gy and 72.8Gy in the DVH of the Tomo IMRT and Proton PBS. The CI was 1.16 and 1.31, and the HI was 0.04 and 0.12 respectively, and the Tomo IMRT was superior to the Proton PBS in dose suitability. Conclusion: The mean dose of PGTV in prostate cancer patients was 3.4% higher in Proton PBS than in Tomo IMRT. This is because the Dose suitability of Tomo IMRT was better, but it is considered to be a small difference to be seen as a significant result. However, the results of the two methods were 51.2% in D 25% and 55.7% less in the average dose of bladder, which could reduce the side effects of patients in proton PBS.

Search for Plant Extracts with Protective Effects of Pancreatic Beta Cell against Oxidative Stress (산화적 스트레스에 대한 췌장 베타 세포 보호활성 식물추출물 탐색)

  • Lee, Dong-Sung;Jeong, Gil-Saeng;An, Ren-Bo;Li, Bin;Byun, Erisa;Kim, Youn-Chul
    • Korean Journal of Pharmacognosy
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    • v.39 no.4
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    • pp.335-340
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    • 2008
  • Diabetes mellitus is metabolic disorder characterized by hyperglycemia caused by insufficient insulin secretion or insulin receptor insensitivity to endogenous insulin. It is well-known that hyperglycemia is one of the main causes of oxidative stress in both type 1 and 2 diabetes. Oxidative stress is related by death of pancreatic ${\beta}$ cell and dysfunction of ${\beta}$ cell. Although ${\beta}$ cell death or dysfunction is induced by many substances or molecules, increased evidences that oxidative stress plays a crucial role in ${\beta}$ cell death or dysfunction. Considering the importance of oxidative stress in the pathogenesis of diabetes mellitus, we investigated the cytoprotective effects against hydrogen peroxide-induced oxidative stress in pancreatic ${\beta}$ cell line RIN-m5F cell. 110 Plant sources were collected in Mt. Baek-du, and extracted with methanol. These extracts had been screened the protective effects against hydrogen peroxide-induced oxidative damage in RIN-m5F cells at 50 and 200 ${\mu}g$/ml. Of these, ten methanolic extracts, aerial part of Erigenron cannadensis, aerial part of Lespedeza juncea, whole plant of Alopecurus aequalis, fruit of Lycium chinense, leaf of Morus alba, rhizome of Polygonatum odoratum, root of Ampelosis japonica, whole plant of Ranunculus japonicus, aerial part of Polygonum sieboldii, rhizome of Arisaema amurense var. violaceum showed significant protective effects against hydrogen peroxide-induced oxidative damage in pancreatic ${\beta}$ cell line RIN-m5F cell.

Photoprotective Effects of Soybean Extract against UV-Induced Damage in Human Fibroblast and Hairless Mouse Model

  • Cho, Young-Chang;Han, Jae-Bok;Park, Sang-Ik
    • Journal of Animal Reproduction and Biotechnology
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    • v.34 no.1
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    • pp.20-29
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    • 2019
  • Soy isoflavones have been reported to possess many physiological activities such as antioxidant activity and inhibition of cancer cell proliferation. This study investigated the photoprotective effects of soybean extract in human fibroblast cell line and hairless mice model. Human fibroblast was treated with soybean extract before and after ultraviolet B (UVB; 290-302 nm) irradiation. In the soybean extract treated group, the cells showed better resistance to ultraviolet (UV) than control group. The amount of type I collagen recovered from the soybean treated group was higher than the vehicle group exposed to UV-induced damage. Moreover, increased expression of metalloproteinases-1 as a result of UV irradiation was suppressed by the soybean extract. Female mice were orally administered soybean extract and irradiated with UVB light for 8 weeks. The effects of the soybean extract on the skin appearance, collagen deposition and epidermal thickness in the UV-damaged mouse skin were analyzed using histopathological methods. In soybean extract treated group, the skin had a better morphology than that of the control group. Furthermore, the amount of type I collagen was increased and overexpression of MMP-1 was reduced in the soybean extract group compared to vehicle group. Additionally, up-regulation of pro-inflammatory cytokines induced by UV irradiation was suppressed by dietary soybean extract treatment. It appears that soybean extract had a photoprotective effect, including anti-aging and anti-inflammatory effect, from UV-induced damage in not only human fibroblast, but also hairless mice. We confirmed that these effects were possibly due to promotion of collagen synthesis and inhibition of MMP-1 expression.