• Radiation Oncology Journal
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• v.36 no.3
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• pp.248-253
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• 2018

Radiation protection in the scrotum to reduce the risk of genetic effect in the future is very important. This study aimed to measure the scrotal dose outside the treatment fields by using the radio-photoluminescence glass dosimeter (RPLGD). The characteristics of RPLGD model GD-302M were studied. Scattered dose to scrotum was measured in one liposarcoma case with the prescribed dose of 60 Gy. RPLGDs were placed in three different locations: one RPLGD was positioned at the posterior area which closer to the scrotum, and the other two RPLGDs were placed between the penis and the scrotum. Three RPLGDs were employed in each location. The scattered doses were measured in every fraction during the whole course of treatment. The entire number of 100 RPLGDs showed the uniformity within ±2%. The signal from RPLGD demonstrated linear proportion to the radiation dose (r = 0.999). The relative energy response correction factor was 1.05. The average scrotal dose was 4.1 ± 0.9 cGy per fraction. The results presented a wide range since there was a high uncertainty during RPLGD placement. The total scrotal dose for the whole course of treatment was 101.9 cGy (1.7% of the prescribed dose). The RPLGD model GD-302M could be used to measure scattered dose after applying the relative energy correction factor.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1992.11a
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• pp.123-127
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• 1992

When MOS devices is exposed to radiation, radiation effects of P-type MOS capacitor can cause modulation and/or degradation in devices characteristics and its operating life. The oxide layer is grown in $O_2$+T.C.E. and its thickness ranges from 40 to 80 nm. Irradiations on MOS capacitor were performed by Cobalt-60 gamma ray source and total dose ranges from $10^4$ to $10^8$ rads. The radiation effect on electrical conduction characteristics(I-V) in MOS capacitor was measured as a function of gate oxide thickness and total dose. From the experimental result, I-V characteristics is found to be influenced strongly by total dose in irradiated p-type MOS capacitors. The ohmic current is dependant on of total dose in irradiated P-type MOS capacitors. This results are explained using surface states at interface radiation-induced traps.

• Radiation Oncology Journal
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• v.12 no.2
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• pp.219-223
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• 1994

This paper describes the basic data measurements for total body irradiation with 6 Mv photon beam including compensators design. The technique uses bilateral opposing fields with tissue compensators for the head, neck, lungs, and legs from the hip to toes. In vivo dosimetry was carried out for determining absorbed dose at various regions in 7 patients using diode detectors(MULTIDOSE,k Model 9310, MULTIDATA Co., USA). As a results, the dose uniformity of${\pm}3.5{\%}$(generally, within${\pm}10{\%}$can be achieved with out total body irradiation technique.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.165-168
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• 2008

The experimental results of exposing IGBT (Insulated Gate Bipolar Transistor) samples to gamma radiation source show shifting of threshold voltages in the MOSFET and degradation of carrier mobility and current gains. At low total dose rate, the shift of threshold voltage is the major contribution of current increases, but for more than some total dose, the current is increased because of the current gain degradation occurred in the vertical PNP at the output of the IGBTs. In the paper, the collector current characteristics as a function of gate emitter voltage (VGE) curves are tested and analyzed with the model considering the radiation damage on the devices for gate bias and different dose. In addition, the model parameters between simulations and experiments are found and studied.

• Journal of Nutrition and Health
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• v.37 no.1
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• pp.31-37
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• 2004

Curcumin, a natural compound extracted from rhizomes of Curcuma longa, has been shown to possess potent anti-inflammatory and anti-tumor activity. The mechanism by which curcumin initiates apoptosis remains poorly understood. In this study, we investigated the effects of curcumin on caspase-3 activity and protein expression of procaspase-3, Bcl-2, Bax, total Akt and phosphorylated Akt in SW480 human colon cancer cell. We cultured SW480 cells in the presence of various concentrations (0, 10, 20 or 30 uM) of curcumin. Curcumin inhibited colon cancer cell growth in a dose-dependent manner (p < 0.05). Caspase-3 activity was significantly increased dose-dependently in cells treated with curcumin (p < 0.05), concisely procaspase-3 expression was significantly decreased. Bcl-2 levels were decreased dose-dependently in cells treated with curcumin (p < 0.05), but Ben remained unchanged. In addition, phosphorylated Akt levels and total Akt levels were markedly lower in cells treated with 20 uM of curcumin treatment (p < 0.05), In conclusion, we have shown that curcumin inhibits cell growth and induces apoptosis in SW480 human colon cancer cell lines via Akt signal pathway.

• Proceedings of the PSK Conference
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• 2003.04a
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• pp.309.2-310
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• 2003

The pharmacokinetics and pharmacodynamics of torasemide were evaluated after an intravenous administration of the same total dose of torasemide at a dose of 1 mg/kg to rabbits with different infusion times, 1 min (treatment I), 30 min (treatment II), and 2 h (treatment III). The loss of water and electrolytes in urine induced by torasemide was immediately replaced with infusion of equal volume of lactated Ringer…s solution. (omitted)

• Nuclear Engineering and Technology
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• v.56 no.3
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• pp.1108-1115
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• 2024

Assuring physical security for Micro Modular Reactors (MMRs) will be key to their licensing. Economic constraints however require changes in how the security objectives are achieved for MMRs. A promising new approach is the so-called performance based (PB) approach wherein the regulator formally sets general security objectives and leaves it to the licensee to set their own specific acceptance criteria to meet those objectives. To implement the PB approach for MMRs, one performs a consequence-based analysis (CBA) whose objective is to study hypothetical malicious attacks on the facility, assuming that intruders take control of the facility and perform any technically possible action within a limited time before an offsite security force can respond. The scenario leading to the most severe radiological consequences is selected and studied to estimate the limiting impact on public health. The CBA estimates the total amount of radionuclides that would be released to the atmosphere in this hypothetical scenario to determine the total radiation dose to which the public would be exposed. The predicted radiation exposure dose is then compared to the regulatory dose limit for the site. This paper describes application of the CBA to four different MMRs technologies.

• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.179-184
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• 2013

The biological effects of radiation are dependent on the dose rate and dose of radiation. In this study, effects of dose and dose rate using whole body radiation on plasma cytokines and blood count from male BALB/c mice were evaluated. We examined the blood and cytokine changes in mice exposed to a low (3.49m Gy $h^{-1}$) and high (2.6 Gy $min^{-1}$) dose rate of radiation at a total dose of 0.5 and 2 Gy, respectively. Blood from mice exposed to radiation were evaluated using cytokine assays and complete blood count. Peripheral lymphocytes and neutrophils decreased in a dose dependent manner following high dose rate radiation. The peripheral lymphocytes population remained unchanged following low dose rate radiation; however, the neutrophils population increased after radiation. The sera from these mice exhibited elevated levels of flt3 ligand and granulocyte-colony-stimulating factor (G-CSF), after high/low dose rate radiation. These results suggest that low-dose-rate radiation does not induce blood damage, which was unlike high-dose-rate radiation treatment; low-dose-rate radiation exposure activated the hematopoiesis through the increase of flt3 ligand and G-CSF.

• Journal of radiological science and technology
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• v.46 no.6
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• pp.509-517
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• 2023

This study analyzed imaging conditions and exposure index through clinical information collection and dose calculation programs in coronary angiography examinations. Through this, we aim to analyze the effective dose according to examination conditions and provide basic data for dose optimization. In this study, ALARA(As Low As Reasonably Achievable)-F(Fluoroscopy), a program for evaluating the radiation dose of patients and the collected clinical data, was used. First, analysis of imaging conditions and exposure index was performed based on the data of the dose report generated after coronary angiography. Second, after evaluating organ dose according to 9 imaging directions during coronary angiography, with the LAO fixed at 30°, dose evaluation was performed according to tube voltage, tube current, number of frames, focus-skin distance, and field size. Third, the effective dose for each organ was calculated according to the tissue weighting factors presented in ICRP(International Commission on Radiological Protection) recommendations. As a result, the average sum of air kerma during coronary angiography was evaluated as 234.0±112.1 mGy, the dose-area product was 25.9±13.0 Gy·cm², and the total fluoroscopy time was 2.5±2.0 min. Also, the organ dose tended to increase as the tube voltage, milliampere-second, number of frames, and irradiation range increased, whereas the organ dose decreased as the FSD increased. Therefore, medical radiation exposure to patients can be reduced by selecting the optimal tube voltage and field size during coronary angiography, maximizing the focal-skin distance, using the lowest tube current possible, and reducing the number of frames.

• The Journal of Korean Society for Radiation Therapy
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• v.12 no.1
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• pp.112-116
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• 2000

Purpose : The vertex scalp is always tangentially irradiated during total skin electron beam(TSEB) This study was discuss to the dose distribution at the vertex scalp and to evaluate the use of an electron reflector. positioned above the head as a means of improving the dose uniformity. Methods and Materials Vetex dosimetry was performed using ion-chamber and TLD. Measurements were 6 MeV electron beam obtained by placing an acrylic beam speller in the beam line. Studies were performed to investigate the effect of electron scattering on vertex dose when a lead reflector $40{\times}40cm$ in area, was positioned above the phantom. Results : The surface dose at the vertex, in the without of the reflector was found to be less than $37.8\%$ of the skin dose. Use of the lead reflector increased this value to $62.2\%$ for the 6 MeV beam. Conclusion : The vertex may be significantly under-dosed using standard techniques for total skin electron beam. Use of an electron reflector improves the dose uniformity at the vertex and may reduce or eliminate the need for supplemental irradiation.