• Title/Summary/Keyword: radiation concentration

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A Realistic Human Exposure Assessment of Indoor Radon released from Groundwater (지하수로부터 방출된 라돈에 의한 현실적인 체내축적량 평가)

  • Yu, Dong-Han;Han, Moon-Hee
    • Journal of Radiation Protection and Research
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    • v.27 no.2
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    • pp.121-126
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    • 2002
  • The work presents a realistic human exposure assessment of indoor radon released from groundwater in a house. At first, a two-compartment model is developed to describe the generation and transfer of radon in indoor air from groundwater. The model is used to estimate radon concentrations profile of indoor air in a house us]ng by showering, washing clothes, and flushing toilets. Then, the study performs an uncertainty analysis of model input parameters to quantify the uncertainty in radon concentration profile. In order to estimate a daily internal dose of a specific tissue group in an adult through the inhalation of such indoor radon, 3 PBPK(Physiologically-Based Pharmaco-Kinetic) model is developed. Combining indoor radon profile and PBPK model is used to a realistic human assessment for such exposure. The results obtained from this study would be used to the evaluation of human risk by inhalation associated with the indoor radon released from groundwater.

A Method of Estimating Radionuclide Accumulation in Coolant Purification System (원자력발전소 냉각수 정화계통의 핵종누적량 예측기법)

  • Whang, Joo-Ho;Lee, Jae-Min
    • Journal of Radiation Protection and Research
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    • v.22 no.3
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    • pp.183-193
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    • 1997
  • The amount and kinds of radionuclide contained in waste volume should be known to prepare for occupational exposure management, perform safety assessment and finally to license a repository. Although the volume of filters and resins are small, activities of them comprise most of the radioactivity that made during power generation. This study aims at developing a method of estimating the radionuclide accumulation at the filters and resins of coolant systems. In this study, accumulated amount of radionuclides is estimated by a computer program which makes use of instantaneous decontamination factor, DF, instead of average DF. A FORTRAN program was developed for the estimation. Data from in-plant source-term measurements at Rancho-Seco nuclear power plant in the United States are employed for verification of the estimating method. And experimental data are employed, too. The instantaneous-DF-method showed smaller error than the average-DF-method. Accumulated amount of radionuclides can be calculated with only the DF and the radionuclide concentration, which are measured periodically according to the operating guide. However, especially, when the operating condition of nuclear power plant changes rapidly, the measuring term of DF and radionuclide should be shortened to ensure the accurate estimation.

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Feasibility in Differentiation of Resistance of Rice Varieties to Brown Planthopper (Nilaparvata lugens Stal) using Radisoisotope (P-32) Tracer-Technique (P-32를 이용한 벼멸구(Nilaparvata lugens Stal) 저항성 검정법에 관한 연구)

  • Chung K.H.;Kwon S.H.;Choi S.Y.
    • Korean journal of applied entomology
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    • v.20 no.4 s.49
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    • pp.207-211
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    • 1981
  • It has been documented that the resistance to planthoppers is attributed to the feeding preference of the insects. This might be related to difference in the amount of feeding plant sap between resistant and susceptible hosts. In this aspect, this study was conducted to verify it and to develop an effective screening method for resistance to planthoppers by tracer technique. An effective P-32 labelling of rice seedlings at $2\~3$ leaf stage was dipping the roots in concentration of $0.1{\mu}Ci/ml$ solution for 48 hours. Radioactivity was significantly higher in planthopers fed on susceptible variety for 48 hours as compared to those fed on resistant variety. Radioactivity of adults was higher than that of nymphs and also higher in female than male. The results were highly correlated to that indicated by the feeding preference of the insects and therefore, considered to be valid for a screening technique.

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Effects of Low Dose $\gamma$ Radiation on Callus Growth of Lithospermum erythrorhizon S. (지치 (Lithospermum erythrorhizon S.) Callus 생장에 미치는 저선량 $\gamma$선의 효과)

  • 황혜연;김재성;이영복
    • Korean Journal of Plant Tissue Culture
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    • v.28 no.6
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    • pp.305-310
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    • 2001
  • The effect of low dose ${\gamma}$-radiation on the callus growth of Lithospermum erythrorhizon S. cultured on different medium and lighting condition was investigated. The 8 Gy irradiation stimulated callus growth on LS medium supplemented with BA 2 mg/L and NAA 2 mg/L, however, the growth of callus was more effective on LS medium supplemented with BA 1 mg/L and NAA 1 mg/L under 16 hrs day light. And on the LS medium containing IAA 0.2 mg/L, 16 Gy irradiation increased the callus growth by supplement with kinetin 2 mg/1 and the effect of kinetin was higher than BA at same concentration. The growth of callus was more vigorous on LS medium than MS medium in general. On M-9 medium, the growth of callus was poor regardless lighting conditions, however, by ${\gamma}$-ray irradiation of 16 Gy or 30 Gy, callus growth rates were increased by 30% or more than 30%, especially, under 16 hrs day light condition.

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Synergistic Effect of Resveratrol and Radiotherapy in Control of Cancers

  • Kma, Lakhan
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.11
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    • pp.6197-6208
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    • 2013
  • Cancers will continue to be a threat to health unless they can be controlled by combinations of treatment modalities. In this review, evaluate the role of resveratrol (RSV) as a radiosensitizing agent was evaluated and underlying mechanisms holistically explored in different cancer models focusing on therapeutic possibilities. The ability of RSV to modify the effect of radiation exposure in normal and cancer cells has indeed been shown quite convincingly, the combination of RSV and IR exhibiting synergistic effects on different cancer cells. This is relevant since controlled exposure to IR is one of the most frequently applied treatments in cancer patients. However, radiotherapy (XRT) treatment regimes are very often not effective in clinical practice as observed in patients with glioma, prostate cancer (PCa), melanoma, for example, largely due to tumour radioresistant properties. Sensitization of IR-induced apoptosis by natural products such as RSV is likely to be relevant in cancer control and treatment. However, all cancers do not respond to RSV+IR in a similar manner. Therefore, for those such as the radioresistant PCa or melanoma cells, the RSV+IR regime has to be very carefully chosen in order to achieve effective and desirable outcomes with minimum toxicity to normal cells. They are reports that the highest concentration of 100 ${\mu}M$ RSV and highest dose of 5 Gy IR are sufficient to kill cells by induction of apoptosis, indicating that RSV is effective in radiosensitizing otherwise radioresistant cells. In general, it has been shown in different cancer cells that RSV+XRT effectively act by enhancing expression of anti-proliferative and pro-apoptotic molecules, and inhibiting pro-proliferative and anti-apoptotic molecules, leading to induction of apoptosis through various pathways, and cell death. If RSV+XRT can suppress the signature of cancer stemness, enhance the radiosensitivity by either targeting the mitochondrial functionality or modulating the tumour necrosis factor-mediated or Fas-FasL-mediated pathways of apoptosis in different cancers, particularly in vivo, its therapeutic use in the control of cancers holds promise in the near future.

Selective separation of Strontium in the solution containing Calcium by Supported Liquid Membrane (함침형 액막을 이용한 Calcium 함유 용액으로부터 Strontium의 선택적 분리)

  • Choi, Young-Woo;Moon, Seung-Hyeon;Lee, Chang-Woo
    • Journal of Radiation Protection and Research
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    • v.24 no.1
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    • pp.9-15
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    • 1999
  • In order to separate $Sr^{2+}$ selectively from environmental sample solutions containing $Ca^{2+}$, supported liquid membranes(SLM) were prepared and their characteristics of separation were investigated. The contents of carriers, DC18C6 and DNNS, in SLM affected the permeabilities of metal ions and selectivities of $Sr^{2+}$. The selectivity of $Sr^{2+}$ reached to 93.3% in a SLM with 0.1 M DC18C6 and 25 mM DNNS. When the ratio of $Sr^{2+}$ to $Ca^{2+}$ concentration in the feed solution was in the range of 1/25 to 1/50, the selectivity of $Sr^{2+}$ was greater than 90 %. Therefore, it is considered that the SLM prepared in this study is capable of treating environmental sea-water samples for strontium measurement.

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Measurement of Radon and its Daughters Concentration in Air (공기중 라돈 및 라돈 자핵종의 농도 측정)

  • Park, Y.W.;Ha, C.W.;Ro, S.G.
    • Journal of Radiation Protection and Research
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    • v.14 no.2
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    • pp.23-29
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    • 1989
  • A Lucas cell was established and calibrated by using the double layer tube standard radon source. The calibration factors were 0.031$\pm$0.002 (pCi/l)/(cph/Cell) at room temperature, and 0.029$\pm$0.001 (pCi/l)/(cph/Cell) at $50^{\circ}C$. Radon and its daughters concentrations were measured in a room air for the demonstrating purpose. The concentrations of 222 Rn, $^{218}Po,\;224\;Pb,\;and\;^{214}Bi$ were 0.87, 0.53, 0.35 and 0.26 pCi/l. The total eqilibrium factor was around 0.40 and the WL is $3.33{\times}10^{-3}$, resulting in 30 mrem/yr at this place.

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Symptom Occurrence Related to Disease Characteristics of Adult Patients with Cancer (성인 암환자의 질병 특성에 따른 증상발생 정도)

  • Hur, Hea-Kung;Lee, Eun-Hyun;Lee, Won-Hee;So, Hyang-Sook;Chung, Bok-Yae;Kang, Eun-Sil
    • Korean Journal of Adult Nursing
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    • v.14 no.3
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    • pp.411-417
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    • 2002
  • Purpose: This study was to investigate symptom occurrence related to the disease characteristics of patients with cancer. Method: A total of 301 patients with cancer participated in this study. The participants were recruited from University Hospitals located in Seoul, Wonju, Kwangju, Daegu, and Pusan. Data collection was performed by using a questionnaire on symptom occurrence. The obtained data was analyzed using SPSS computer program that included descriptive statistics, Pearson correlation, one-way ANOVA, and t-test. Result: The mean score of fatigue was the highest (3.24), followed by loss of appetite, lack of concentration, change in appearance, pain, insomnia, change in bowel pattern, nausea/vomiting, coughing, and dyspnea. Most symptoms were significantly correlated with each other. The level of symptom occurrence in patients with lung cancer or cervix cancer was significantly higher than the level in patients with stomach cancer. Patients receiving radiation therapy or a combined therapy of radiation therapy and chemotherapy experienced significantly higher level of symptom occurrence than those receiving chemotherapy only. Also, female patients experienced higher level of symptom occurrence than male patients did. Conclusion: The sites of cancer, types of treatment, and gender influence the level of symptom occurrence of patients with cancer. Thus, these variables should be considered when assessing and planing for symptom occurrence of patients with cancer.

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A Study on Mesoscale Atmospheric Dispersion of Radioactive Particles Released from Nuclear Power Plants (원전부지 주변 국지순환에 따른 방사성 물질의 대기확산 특성 연구)

  • Lee, Gab-Bock;Lee, Myung-Chan;Song, Young-I1
    • Journal of Radiation Protection and Research
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    • v.22 no.4
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    • pp.273-288
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    • 1997
  • A three dimensional sea-land breeze model and Lagrangian particle dispersion model have been employed for the study on the mesoscale atmospheric dispersion of radioactive materials released from Wolsung NPPs. In this study, atmospheric dispersion simulations are carried out under two synoptic weather conditions : the geostrophic flow is a weak northerly wind(CASE 1) and a strong northerly wind(CASE 2) on a clear day in spring. The results show that atmospheric dispersion is affected by sea-land breeze and the recirculation of particles by the change of wind direction between sea breeze and land breeze plays an important role in atmospheric concentration distribution of radoactive materials.

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Effects of Uranyl Nitrate on $Na^{+}-K^{+}$Adenosine Triphosphatase Activity and Excretion of $Na^{+}\;and\;K^{+}$in Rats (Rat에서 $Na^{+}-K^{+}$ATPase 활성도와 $Na^{+},\;K^{+}$ 배설에 미치는 질산 우라늄의 영향)

  • Lee, Kee-Ho;Yun, Taik-Koo
    • Journal of Radiation Protection and Research
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    • v.14 no.1
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    • pp.1-7
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    • 1989
  • In order to evalulate the cause of polyuric acute tubular necrosis, we measured electrolytes, $Na^{+}\;and\;K^{+}$ excreted in urine, and activities of $Na^{+}-K^{+}$adenosine triphosphatase ($Na^{+}-K^{+}$ATPase) Excretion of $Na^{+}\;and\;K^{+}$ significantly increased in 24hr exposure on the uranyl nitrate and then decreased below the normal level after 3 days. The concentration of $Na^{+}\;and\;K^{+}$ in urines of the rats treated uranyl nitrate was less than that of the normal rats. The activities of $Na^{+}-K^{+}$ATPase decreased only in the group treated with high dose group of uranyl nitrate (30mg/kg BW) on the 3rd day but were not changed in the low dose groups(5 mg/kg BW and 15mg/kg BW).

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