• 방사선산업학회지
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• 제17권3호
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• pp.219-224
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• 2023

A high-efficiency underwater radiation monitoring system, HydroGamma, has been developed for detecting ¹³⁷Cs and ¹³¹I in the event of waterborne radiation contamination. The system consists of a 3-inch NaI (Tl) detector, solar panels for power supply, data acquisition and transmission modules, and batteries. HydroGamma also includes a ⁴⁰K calibration source for remote performance evaluation and energy calibration. In this study, some simulations and experiments were carried out to evaluate the minimum detectable activities (MDA) of HydroGamma. We installed the HydroGamma at Tapjeongho Lake in Nonsan-si and acquired background data since MDA is calculated based on the experimental background data. The results show that the minimum detectable activities for ¹³⁷Cs and ¹³¹I were 1.78Bq L^-1 and 1.81Bq L^-1, respectively even though the gamma rays emitted from ⁴⁰K(1,460 keV) affect the minimum detectable activities for them.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 추계 학술발표
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• pp.74-75
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 춘계 학술발표
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• pp.168-169
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• 2009

See Full Text

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.174-174
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• 2004

It is necessary to perform the radionuclide inventory assessment for the disposal of low and intermediate radioactive waste containers. The $\gamma$ nuclide analyzer can be used for the assessment of containers. However, if the radioactivity in the containers is extremely low or high, radionuclide inventory of the containers can not be evaluated properly. Also, gamma scanning method is time consuming and has economical burden to the utilities.(omitted)

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 추계 학술발표
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• pp.42-43
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• 2009

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2011년도 추계 학술발표회 및 심포지엄
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• pp.212-213
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• 2011

The biological effects of low dose ionizing radiation (LDIR) remain insufficiently understood. We examined for the scientific evidence to show the biological effects of LDIR using radiation-sensitive immune cells. We found that Ikaros protein was responsed to low dose-dependent effects of gamma radiation in IM-9 B lymphocytes. Ikaros encodes zinc finger transcription factors that is important regulators of a hematopoietic stem cells (HSCs) progression to the B lymphoid lineage development, differentiation and proliferation. In this study, we observed that cell proliferation was enhanced from 10% to 20% by LDIR (0.05 Gy) in IM-9 B lymphocytes. The Ikaros protein was phosphorylated in its serine/threonine (S/T) region and decreased its DNA binding activity in the cells exposed to LDIR. We found that Ikaros phosphorylation was up-regulated by CK2/AKT pathway and the residues of ser-304 and ser-306 in Ikaros was phosphorylated by LDIR. We also observed that Ikaros protein was localized from the nucleus to the cytoplasm after LDIR and bound with Autotaxin (ENPP2, ATX) protein, stimulating proliferation, migration and survival of immune cells. In addition, we found that the lysoPLD activity of ATX was dependent on Ikaros-ATX binding activity. These results indicate that the Ikaros is an important regulator of immune activation. Therefore, we suggest that low dose ionizing radiation can be considered as a beneficial effects, stimulating the activation of immune cells.

• 대한방사선방어학회:학술대회논문집
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• 대한방사선방어학회 2009년도 춘계 학술발표
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• pp.152-153
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• 2009

• Journal of Radiation Protection and Research
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• 제26권4호
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• pp.393-398
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• 2001

매년 병원에서 사용 후 폐기되는 비가연성 폐기물은 ${\gamma}$-선과 ${\beta}$-선을 방출하지만 방사능은 주변방사능 수준으로 매우 낮다. 이를 측정하기 위한 기존의 방법은 비효율적이고 복잡하므로, 좀더 간단한 방법이 긴요하다. 본 논문에서는 측정 방사선의 특성상 핵종에 따라 다른 측정방법을 사용하였는데, ${\gamma}$-선 방출 핵종은 표준시료로부터 효율곡선식을 도출하여 미지의 방사능을 측정하였다 ${\beta}$-선 방출 핵종은 Monte Carlo 시뮬레이션을 통해 계측 효율을 예측하고 표면장벽형계측기로 측정하여 미지의 방사능 양을 결정하는 새로운 방법을 제시하였다. 연구결과에 의하면 이론적 계산치와 표면장벽형 계측기를 이용하면 전처리를 필요로하는 액체섬광계수기를 이용하지 않고 또한 계측효율을 결정하기 위한 비경제적인 표준시료 측정시험과정 없이도 저에너지 방사선을 약 17% 오차 범위내에서 결정할 수 있다고 판단된다.

• Journal of Microbiology and Biotechnology
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• 제24권1호
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• pp.127-131
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• 2014

While searching for lactic acid bacteria that can restore aging-impaired immune responses, we isolated the Toll-like receptor (TLR) 2/NF-${\kappa}B$-activating strain Lactobacillus plantarum HY7712 from kimchi and investigated its immunomodulating effect in whole-body ${\gamma}$-irradiated mice. Exposure to HY7712 strongly activated NF-${\kappa}B$ signaling in RAW264.7 cells, but inhibited lipopolysaccharide-stimulated NF-${\kappa}B$ activation. Moreover, HY7712 protected against the downregulation of interferon (IFN)-${\gamma}$ and upregulation of interleukin (IL)-13 caused by ${\gamma}$-irradiation in mice. In mice, ${\gamma}$-irradiation impaired NK-cell activity against YAC-1 tumor cells, but following HY7712 exposure, the activity of NK cells was restored to 91.5% of the level measured in control mice (p < 0.05). These findings suggest that HY7712 activates the TLR2/NF-${\kappa}B$ signaling pathway and protects against the impairment of NK-cell activity caused by ${\gamma}$-irradiation or aging.

• Journal of Radiation Protection and Research
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• 제29권1호
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• pp.9-15
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• 2004

방사선에 의해 유도되는 사람 말초혈액 림프구 미소핵 관찰빈도를 높이면서 생물학적 선량평가법으로서 활용 가능성을 확인하고자 본 연구를 수행하였다. 우선 5명의 건강한 사람으로부터 혈액을 제공 받아 선량영역을 0에서 800cGy로 하여 감마선$(^{137}Cs)$을 조사 한 후 김사와 아크리딘 오렌지 형광 염색하고 미소핵 출현빈도를 비교하였다. 아크리딘 오렌지 염색법을 이용하여 미소핵을 관찰하였을 때, 김사 염색법에 비교하여 적갈색의 비특이성 과립과 녹황색의 DNA가 붉은색의 세포질을 배경으로 명확히 구별되었을 뿐만 아니라 선량이 증가하면서 검출율도 높았다. 아울러, 말초혈액 T와 B-림프구에 대하여 선량영역을 0에서 50cGy로 하여 방사선을 조사한 후 미소핵 출현빈도를 아크리딘 오렌지 염색하여 김사염색과 비교한 바, B-림프구에서 선량이 증가하면서 적어도 2배 이상 높게 관찰되었다. 본 실험 결과, 사람 말초 혈액 B-림프구를 대상으로 한 아크리딘 오렌지 형광염색 미소핵 분석법은 저선량 방사선 인체영향 평가나 과피폭 선량추정시 활용이 가능 할 것으로 생각된다.