• Journal of Radiation Protection and Research
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• v.26 no.4
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• pp.347-356
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• 2001

Guarana, a tropical plant is found in powdered for in health food and is very popular soft drink in Brazil as an energy feaster with its high caffeine contents. We examined its radioprotection effects during organogenesis stages of ICR mice by malformations rate and cellular lead 8 the embryo by radiation and analyzed the mechanism of the radioprotection effects in the fetal of ICR mice. The results of this study showed that Guarana reduced clearly the embryonic death rate and teratogenesis rate by radiation. Its radioprotection effect inject be related with its radioprotection effect might be related with its antioxidant effect or free radical scavenger. We need to exposure the Guarana as a potential radioprotection agent. Therefore, we investigated about radiation effects by Guarana using to mice experiments in this paper.

• Fire Science and Engineering
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• v.14 no.3
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• pp.6-12
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• 2000

This paper describes the smoke movement of a fire field model based on a self-developed SMEP(Smoke Movement Estimating Program) code to the simulation of fire induced flows in the two types of compartment space containing the radiation effect under smoke movement in room fire. The SMEP using PISO algorithm solves conservation equations for mass, momentum, energy and species, together with those for the modified k-$\varepsilon $ turbulence model with buoyancy term. Also it solves the radiation equation using the discrete ordinates method. The result of the calculated smoke temperature containing radiation effect has shown reasonable agreement compared with the experimental data. On the other hand, a difference of a lot was found between the temperature predicted by the SMEP with only convection effect and obtained by the experimental result. This seems to come from the radiation effect of $H_2$O and $CO_2$ gas under smoke productions. Thus, the consideration of the radiation effect under smoke in fire may be necessary in order to produce more realistic result.

• Journal of Radiation Protection and Research
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• v.30 no.4
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• pp.197-208
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• 2005

Although little information is available on the underlying mechanisms, various genetic factors have been associated with tissue-specific responses to radiation. In the present study, we explored the possibility whether organ specific gene expression is associated with radiosensitivity using samples from brain, lung and spleen. We examined intrinsic expression pattern of 23 genes in the organs by semi-quantitative RT-PCR method using both male and female C57BL/6 mice. Expression of p53 and p21, well known factors for governing sensitivity to radiation or chemotherapeutic agents, was not different among the organ types. Both higher expression of sialyltransferase, delta7-sterol reductase, leptin receptor splice variant form 12.1, and Cu/Zn superoxide dismutase (SOD) and lower expression of alphaB crystalline were specific for spleen tissue. Expression level of glutathione peroxidase and APO-1 cell surface antigen gene in lung tissue was high, while that of Na, K-ATPase alpha-subunit, Cu/ZnSOD, and cyclin G was low. Brain, radioresistant organ, showed higher expressions of Na, K-ATPase-subunit, cyclin G, and nucleolar protein hNop56 and lower expression of delta7-sterol reductase. The result revealed a potential correlation between gene expression patterns and organ sensitivity, and Identified genes which might be responsible for organ sensitivity.

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.941-948
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• 2024

The effects of radiation on the corrosion of canister materials were investigated for the reliable disposal of high-level radioactive waste. The test specimens were gamma-irradiated at a very low dose rate of approximately 0.1 Gy/h for six and twelve months. The copper and cast iron species were less corroded when irradiated. It is hypothesized that gamma rays suppress the formation of lower-enthalpy species like metal oxides and activate reductive reactions. In contrast, it was difficult to evaluate the effect of radiation on the corrosion of titanium and stainless steel.

• Journal of Korean Neurosurgical Society
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• v.46 no.6
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• pp.564-567
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• 2009

Early delayed radiation effects are known to occur within several months after completing radiotherapy for brain tumors. We present marked changes of magnetic resonance imaging (MRI) scan that occurred one month after radiotherapy in a patient with a pleomorphic xanthoastrocytoma, which was eventually diagnosed as an early delayed radiation effect. Such an early development of dramatic MRI change has not been reported in patients treated with radiotherapy for pleomorphic xanthoastrocytomas.

• Journal of Plant Biotechnology
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• v.40 no.3
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• pp.111-124
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• 2013

Research on the basic interaction of radiation with biological systems has contributed to human society through various applications in pharmaceutical, medicine, agriculture and other technological developments. In the agricultural sciences and food technology sectors, the last few decades have witnessed a large number of pertinent works regarding the utilization of radiation for evolution of superior varieties of agricultural crops of economic importance. This review presents general information about the effect of radiation on plant specificity, dose response, and benefits. There has been summarized of the effects observed after exposure and influenced by several factors including plant characteristics and radiation features. We also report on the effect of ${\gamma}$-irradiations on plants, focusing on metabolic alterations, modifications of growth and development and changes in biochemical pathways.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.130.3-131
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• 2003

Inflammation is a frequent radiation-induced following therapeutic irradiation. Since the upregulation of adhesion molecules on endothelial cell surface has been known to be associated with inflammation, interfering with the expression of adhesion molecules is an important therapeutic target. We examined the effect if allicin, a major component of garlic, on the induction of intercellular adhesion molecule-l (ICAM-1) by gamma-irradiation and the mechanisms of its effect in gamma-irradiated human umbilical vein endothelial cells (HUVECs). (omitted)

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.3
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• pp.858-867
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• 1995

Characteristics of premixed flames in counter-flow system are numerically studied using a detailed chemical reaction mechanism including gas phase radiation. Without radiation effect accounted, low CO and high NO$_{x}$ emission indices are observed, when strain rate decreases, due to increased residence time and higher flame temperature. Higher NO$_{2}$ production has been also observed when two premixed flames are interacting or cold air stream is mixed with burned gas. The rate of NO$_{x}$ production and destruction is dependent upon the diffusional strength of H and OH radicals, the existence of NO and the concentration of HO$_{2}$. For radiating flames, the peak temperature and NO$_{x}$ production rate decreases as the strain rate decreases. At high strain rate, it is found that the effect of radiation on flame is little due to its negligible radiating volume. It is also found that NO$_{x}$ production from the interacting premixed flame is reduced due to reduced temperature resulting from radiation heat loss. It is concluded that the radiation from gas has significant effect of flame structure and on emission characteristics.ristics.

• Radiation Oncology Journal
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• v.7 no.1
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• pp.1-13
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• 1989

Effects of ionizing radiation alone and combined with chemotherapy on tumor growth and it's clonal specificity monitored by changes in distribution of chromosome number were studies in A549 ceil line originated from human adenocarcinoma of the lung. Radiation (300 rad, 600 rad and 900 rad) were delivered with or without 5-FU. Forty eight hours later, 57.5% of growth inhibition of cell w8s seen in cells treated with 5-FU concentration of $0.4{\mu}g/ml$ for 24hr exposure. Cell survival curves after radiation with and without 5-FU were made. Chromosomal analysis of cells in metaphase in control, and in cells treated with 300 rad of radiation, or $0.4{\mu}g/ml$ of 5-FU treatment, and combined treatment of both were done to examine the changes in ploidy and number of chromosome. Radiation combined with S-FU enhanced growth inhibition of A549 cells. However, no evidence of synergegic effects in growth. inhibition was observed in the cells treated with the combination therapy. Pattern of chromosomal distribution of survived cells were shifted from hyperploidy to hypoploidy by single dose of radiation (300 rad). As radiation dose increased a large number of hypoploidy cells were observed. Following treatment of cells with 5-FU, chomosomal distribution of survived cells were also shifted to hypodiploidy which were seen in cells treated with radiation, The ceil treated with 5-FU and fellowed by radiation within 24 hrs had cell with increased number of hypodiploidy cells. Almost same type of chromosomal changes were reproduced in cells treated with combined treatment with radiation and 5-FU. Minor differences were that cells with fewer number of chromosome were more frequent in cells treated with combined therapy. Further increase in cells of hypoploidy (93%) having 1-10 chromosome were induced by additional radiation. Therefore, the enhanced therapeutic effect of 5-FU combined with radiation of A549 cells appeared to be additive rather than synergistic.

• Polymer(Korea)
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• v.35 no.6
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• pp.610-614
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• 2011

In this study, the effect of solvent on the pre-irradiation grafting of VBC(vinylbenzyl chloride) onto a ETFE(polyethylene-co-tetrafluoroethylene) was evaluated. ETFE film was irradiated to generate radical species onto its backbone chain. Each irradiated film was immersed into VBC monomer mixtures diluted with various solvents such as toluene, heptane, and isopropanol etc. for grafting process and then the degree of grafting of each film was measured. FTIR analysis confirmed that the VBC-g-ETFE film was successful prepared. For the films prepared in the various solvents, the mechanical strength and the distribution pattern of the graft polymer over the cross-section of the films were measured and the effect of solvent was evaluated.