• Title/Summary/Keyword: Gamma-ray protection

Search Result 173, Processing Time 0.026 seconds

DIFFERENTIAL EXPRESSION OF RADIATION RESPONSE GENES IN SPLEEN, LUNG, AND LIVER OF RATS FOLLOWING ACUTE OR CHRONIC RADIATION EXPOSURE

  • Jin, Hee;Jin, Yeung Bae;Lee, Ju-Woon;Kim, Jae-Kyung;Lee, Yun-Sil
    • Journal of Radiation Protection and Research
    • /
    • v.40 no.1
    • /
    • pp.25-35
    • /
    • 2015
  • We analyzed the differential effects of histopathology, apoptosis and expression of radiation response genes after chronic low dose rate (LDR) and acute high dose rate (HDR) radiation exposure in spleen, lung and liver of rats. Female 6-week-old Sprague-Dawley rats were used. For chronic low-dose whole body irradiation, rats were maintained for 14 days in a $^{60}Co$ gamma ray irradiated room and received a cumulative dose of 2 Gy or 5 Gy. Rats in the acute whole body exposure group were exposed to an equal dose of radiation delivered as a single pulse ($^{137}Cs$-gamma). At 24 hours after exposure, spleen, lung and liver tissues were extracted for histopathologic examination, western blotting and RT-PCR analysis. 1. The spleen showed the most dramatic differential response to acute and chronic exposure, with the induction of substantial tissue damage by HDR but not by LDR radiation. Effects of LDR radiation on the lung were only apparent at the higher dose (5 Gy), but not at lower dose (2 Gy). In the liver, HDR and LDR exposure induced a similar damage response at both doses. RT-PCR analysis identified cyclin G1 as a LDR-responsive gene in the spleen of rats exposed to 2 Gy and 5 Gy gamma radiation and in the lung of animals irradiated with 5 Gy. 2. The effects of LDR radiation differed among lung, liver, and spleen tissues. The spleen showed the greatest differential effect between HDR and LDR. The response to LDR radiation may involve expression of cyclin G1.

Radiation Protection Effect of Protaetia Brevitarsis Larvae Extracts on Blood and Prostate in Male Rats Irradiated with Co-60 Gamma-ray (흰점박이꽃무지 유충 추출물이 Co-60 감마선에 조사된 수컷 흰쥐의 혈구 및 전립선에 미치는 방사선 방호효과)

  • Jeong, Geun-Woo;Kim, Jang-Oh;Lee, Yoon-Ji;Kim, Hae-Suk;Jeon, Chan-Hee;Choi, Jae-Gyeong;Joo, Sung-Hyun;Min, Byung-In
    • Journal of radiological science and technology
    • /
    • v.44 no.2
    • /
    • pp.117-122
    • /
    • 2021
  • This study is desinged to examine for radiation protection effect of Protaetia Brevitarsis Larvae extracts on the blood and prostate of male rat as a natural radiation protection agent. 5 groups were classified using 90 male rat as experimental animals. Each group was clssified as normal control group (NC Group), the group administered protaetia brevitarsis larvae extracts (PBE Group), irradiated group (IR Group), irradiated group after administration of protaetia brevitarsis larvae extracts (PBE+IR Group), the group administered protaetia brevitarsis larvae extracts after irradiaton (IR+PBE Group). In IR Group, 7 Gy/h of Co-60 gamma ray was irradiated to SD rats. In PBE+IR Group, protaetia brevitarsis larvae extacts wewe injected at 200 mg/kg/day for 14 days before irradiation, In IR+PBE Group, protaetia brevitarsis larvae extract was injeted after irradiation. On the 1, 7 and 21 days after irradiation, the experimental animals were sacrificed to evaluate the changes in blood cell component, superoxide dismutase (SOD) activity, histopathological evaluation of the liver and prostate gland. As a result, the PBE+IR Group and IR+PBE Group showed a significantly recovery of white blood cell (p<0.01, p<0.01), platelet (p<0.01, p<0.01) than the IR Group. It was also confirmed that SOD activity of PBE+IR Group (p<0.01) and IR+PBE Group (p<0.01) was significantly increased than the IR Group. Also PBE+IR Group and IR+PBE Group showed less inflammatory reactions of cystoplasm in the prostate gland than the IR Group. In conclusion, the protaetia brevitarsis larvae have radioprotection effect against blood and prostate gland. It is expected to be useful for research of radiation protection agent.

Radiation Shielding Analysis for the X-ray Facility (X-선 발생장치 시설의 방사선 차폐 해석)

  • Kwon, Seog-Guen;Choi, Ho-Sin;Moon, Philip-S.;Yook, Jong-Chul
    • Journal of Radiation Protection and Research
    • /
    • v.12 no.1
    • /
    • pp.34-39
    • /
    • 1987
  • Radiation shielding analysis for a 6MeV X-ray facility was carried out. The primary and leakage radiation for the facility can be evaluated based on the methodology in NCRP No. 49 and 51. The present study deals with radiation scattering analysis for the outside and inside door of the facility based on the albedo concept. The calculated dose rates were compared with the results of MORSE-CG code calculation and the measured data, resulting in a good agreement, even though there existed some deviation for the inside door. These results can be utilized to the radiation shielding design of the medical and industrial X and gamma ray facilities, and to the safety evaluation of these facilities.

  • PDF

A Study of the Inorganic Scintillator Properties for a Phoswich Detector (Phoswich 검출기 제작을 위한 무기 섬광체 특성 연구)

  • Lee, Woo-Gyo;Kim, Yong-Kyun;Kim, Jong-Kyung;Tarasov, V.;Zelenskaya, O.
    • Journal of Radiation Protection and Research
    • /
    • v.29 no.4
    • /
    • pp.251-256
    • /
    • 2004
  • CsI(Tl), $CdWO_4(CWO),\;Bi_4Ge_3O_{12}(BGO)\;and\;Gd_2SiO_5:Ce(GSO)$ scintillators were studied to manufacture a phoswich detector. The maximum wavelengths of the CsI(Tl), CWO, BGO and GSO scintillators are 550 nm, 475 nm, 490 nm and 440 nm for the radioluminescence, and the absolute light outputs of the CsI(Tl), CWO, BGO and GSO scintillators are 54890 phonon/MeV, 17762 phonon/MeV, 8322 phonon/MeV and 8932 phonon/MeV with a neutral filter, and the decay time of the CsI(Tl), CWO, BGO and GSO scintillators is $1.3{\mu}s,\;8.17{\mu}s$, 213 ns and 37 ns by a single photon method. The phoswich detector which was manufactured with plastic and CsI(Tl) scintillators could separate the ${\beta}$ particle and ${\gamma}$ ray. The phoswich detector could also measure the pulse height spectra of the ${\beta}$ particle and ${\gamma}$ ray by a PSD method.

Radioactive Concentrations in Chemical Fertilizers

  • Gwang-Ho Kim;Jae-Hwan Cho
    • Journal of Radiation Protection and Research
    • /
    • v.47 no.4
    • /
    • pp.195-203
    • /
    • 2022
  • Background: The aim of the present study was to determine radioactive concentrations in fertilizers known to contain essential nutrients. Results of this study could be used as basic data to monitor the impact of chemical fertilizers on the environment and public health. Nitrogen fertilizers, calcium fertilizers, sulfur fertilizers, phosphate acid fertilizers, and potassium chloride fertilizers were used in this study. Materials and Methods: Five chemical fertilizers were pulverized, placed in polyethylene containers, and weighed. The time to measure each specimen was set to be 3,600 seconds for a scintillator-based gamma-ray spectroscopy system. Concentration of gamma radionuclide was analyzed based on obtained spectra. At the end of the measurement, the spectrum file was stored and used to calculate radioactive concentrations using a gamma-ray spectrometer software. Results and Discussion: In the nitrogen fertilizer, 3.49 ± 5.71 Bq/kg of 137Cs, 34.43 ± 7.61 Bq/kg of 134Cs, and 569.16 ± 91.15 of 40K were detected whereas 131I was not detected. In the calcium fertilizer, 5.74 ± 4.40 Bq/kg of 137Cs (the highest concentration among all fertilizers), 22.37 ± 5.39 Bq/kg of 134Cs, and 433.67 ± 64.24 Bq/kg of 40K were detected whereas 131I was not detected. In the sulfur fertilizer, 347.31 ± 55.73 Bq/kg of 40K, 19.42 ± 4.53 Bq/kg of 134Cs, 2.21 ± 3.49 of 137Cs, and 0.04 ± 0.22 Bq/Kg of 131I were detected. In the phosphoric acid fertilizer, 70,007.34 ± 844.18 Bq/kg of 40K (the highest concentration among all fertilizers) and 46.07 ± 70.40 Bq/kg of 134Cs were detected whereas neither 137Cs nor 131I was detected. In the potassium chloride fertilizer, 12,827.92 ± 1542.19 Bq/kg of 40K was and 94.76 ± 128.79 Bq/kg of 134Cs were detected whereas neither 137Cs nor 131I was detected. The present study examined inorganic fertilizers produced by a single manufacturer. There might be different results according to the country and area from which fertilizers are imported. Further studies about inorganic fertilizers in more detail are needed to create measures to reduce 40K. Conclusion: Measures are needed to reduce radiation exposure to 40K contained in fertilizers including phosphoric acid and potassium chloride fertilizers.

The Flow-rate Measurements in a Multi-phase Flow Pipeline by Using a Clamp-on Sealed Radioisotope Cross Correlation Flowmeter (투과 감마선 계측신호의 Cross correlation 기법 적용에 의한 다중상 유체의 유량측정)

  • Kim, Jin-Seop;Kim, Jong-Bum;Kim, Jae-Ho;Lee, Na-Young;Jung, Sung-Hee
    • Journal of Radiation Protection and Research
    • /
    • v.33 no.1
    • /
    • pp.13-20
    • /
    • 2008
  • The flow rate measurements in a multi-phase flow pipeline were evaluated quantitatively by means of a clamp-on sealed radioisotope based on a cross correlation signal processing technique. The flow rates were calculated by a determination of the transit time between two sealed gamma sources by using a cross correlation function following FFT filtering, then corrected with vapor fraction in the pipeline which was measured by the ${\gamma}$-ray attenuation method. The pipeline model was manufactured by acrylic resin(ID. 8 cm, L=3.5 m, t=10 mm), and the multi-phase flow patterns were realized by an injection of compressed $N_2$ gas. Two sealed gamma sources of $^{137}Cs$ (E=0.662 MeV, ${\Gamma}$ $factor=0.326\;R{\cdot}h^{-1}{\cdot}m^2{\cdot}Ci^{-1}$) of 20 mCi and 17 mCi, and radiation detectors of $2"{\times}2"$ NaI(Tl) scintillation counter (Eberline, SP-3) were used for this study. Under the given conditions(the distance between two sources: 4D(D; inner diameter), N/S ratio: $0.12{\sim}0.15$, sampling time ${\Delta}t$: 4msec), the measured flow rates showed the maximum. relative error of 1.7 % when compared to the real ones through the vapor content corrections($6.1\;%{\sim}9.2\;%$). From a subsequent experiment, it was proven that the closer the distance between the two sealed sources is, the more precise the measured flow rates are. Provided additional studies related to the selection of radioisotopes their activity, and an optimization of the experimental geometry are carried out, it is anticipated that a radioisotope application for flow rate measurements can be used as an important tool for monitoring multi-phase facilities belonging to petrochemical and refinery industries and contributes economically in the light of maintenance and control of them.

Radioprotective Effect of Panax Ginseng in Mouse Bone-marrow (생쥐에서 방사선방호제로서의 인삼효과에 관한 연구)

  • Chae, Ki-Moon;Choi, Keun-Hee;Kim, Young-Ho;Kim, Kwang-Yoon;Bom, Hee-Seung;Kim, Ji-Yeul;Lee, Chong-Bin
    • Journal of Radiation Protection and Research
    • /
    • v.22 no.1
    • /
    • pp.1-7
    • /
    • 1997
  • Radiation protection by post-irradiation injection of the ginseng extract in mice was studied. Male ICR mice, 7 weeks old, were orally injected with ginseng extrat(100mg/kg) for 10 days, and with physiologocal saline as the control. Immediately after final injection, mice were whole body irradiated with 5.08Gy(Cs-137 ${\gamma}$-ray, central dose rate : 654Gy/h) which induced Bone marrow death. At 24h after irradiation, micronucleus test and metaphase analysis in bone-marrow were carried, blood cell were counted and the survival rate were carried for 30 days after the irradiation. Stimulated recovery by the extract was observed in thrombocyte count, but that phenomenom was not showed in the erythrocyte and leucocyte counts. The 30-day survival ratio was 5% and 65% for the control and experimental group. Frequencies of micronuclei per 1000 polychromatic erythrocytes were 79.5${\pm}$1.5 in experimental group, 185.9${\pm}$35.8 in control. And Abnormal chromosomes per 50 metaphases were 112 in experimental group and 143 in control.

  • PDF

Protective Effects of a Herb, Artemisia capillaris, Against Radiation-induced DNA Damage (방사선 유도 DNA 손상에 대한 인진쑥의 방어효과)

  • Jo, Sung-Kee;Oh, Heon;Cheon, Eui-Hyun;Jeong, U-Hee;Cho, Nam-Jeong
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.33 no.1
    • /
    • pp.22-27
    • /
    • 2004
  • In the present study, the protective effects of Artemisia capillaris (AC) on the DNA damage induced by $^{60}$ Co ${\gamma}$-rays were evaluated using alkaline single-cell gel electrophoresis (SCGE, comet assay) in the mouse peripheral lymphocytes and micronuclei (MN) formation test in the Chinese hamster ovary (CHO) cells. We also investigated the effect of AC on 8-hydroxy-2'-deoxyguanosine (8-OHdG) formation in the mouse liver and thymus exposed to ${\gamma}$-ray, The tail moment and the frequency of MN, which were markers of DNA damage in the SCGE and MN formation test, were decreased in the groups treated with AC extract before exposure to 200 cGy of ${\gamma}$-ray. We also observed its activities, lowering 8-OHdG level, an index of oxidative DNA damage, in the groups treated with AC extract before whole body ${\gamma}$-irradiation (800 cGy). It is plausible that scavenging of free radicals by AC may have played an important role in providing the protection against the radiation-induced damage to the DNA. These results indicated that AC protects the DNA damage induced by ${\gamma}$-rays and might be a useful radioprotector, especially since it is a relatively nontoxic product.

Study on gamma radiation attenuation and non-ionizing shielding effectiveness of niobium-reinforced novel polymer composite

  • Akman, Ferdi.;Ogul, H.;Ozkan, I.;Kacal, M.R.;Agar, O.;Polat, H.;Dilsiz, K.
    • Nuclear Engineering and Technology
    • /
    • v.54 no.1
    • /
    • pp.283-292
    • /
    • 2022
  • Advanced radiation applications have been widely used and extended to many fields. As a result of this fact, choosing an appropriate shielding material based on the radiation application has become vital. In this regard, the integration of elements into polymer composites has been investigated and contributed to the quantity and quality of radiation shielding materials. This study reports photon attenuation parameters and electromagnetic shielding effectiveness of a novel polymer composite prepared with a matrix reinforced with three different proportions (5, 10, and 15 wt%) of niobium content. Addition of Nb dopant improves both photon attenuation and electromagnetic shielding effectiveness for the investigated composites. Therefore, Nb(15%) polymer composite with highest concentration has been found to be the best absorber for ionizing and non-ionizing radiations. Consequently, the performed analyzes provide evidences that the prepared Nb-reinforced polymer composite could be effectively used as photon radiation attenuator and electromagnetic shielding material.

Development of a TL pellet based on $CaSO_4:Dy$ for Neutron Measurement ($CaSO_4:Dy$ 물질 기반 중성자 측정용 TL소자 개발)

  • Yang, Jeong-Seon;Lee, Jeong-Il;Kim, Jang-Lyul;Kim, Bong-Hwan;Sou, Dong-Sup
    • Journal of Radiation Protection and Research
    • /
    • v.31 no.3
    • /
    • pp.129-134
    • /
    • 2006
  • A TL pellet for a neutron dose measurement (KCT-306) by embedding a $^6Li$-compound into a $CaSO_4:Dy$ phohphor was developed based upon the technical information of KCT-300. The KCT-300 is an another kind of $CaSO_4:Dy$ TL detector shich was developed at KAERI, in which small amounts of $NH_4H_2PO_4$ have been emvedded as a binding material. This paper presented the optimized manufacturing condition of KCT-306 and compared its sensitivity with that of the commercialized neutron TL pellets. $CaSO_4:Dy$ Phosphor with grain size ranging less than $45{\mu}m$ are used for the KCT-306. The optimum $CaSO_4:Dy$ TL phosphor, $^6Li$-compounds and P-compound as the binding material are determined as 20-40wt%, 50-70wt% and 20wt%. The TL pellet combination of our KCT-306/KCT-300, TLD-600/TLD-700 and TLD-600H/TLD-700H(Harshaw) have been irradiated in the neutron/gamma mixed fields from a $D_2O$ moderated $^{252}Cf$ neutron source. The KCT-300, TLD-700 and TLD-700H were used at the same time as gamma ray discriminators in the neutron/gamma mixed fields. It was found that the neutron/gamma response ratios of KCT-306/KCT-300, which were developed in this study, were approximately 4 times higher than those of the commercial TLD-600H/TLD-700H.