• Title/Summary/Keyword: radiation concentration

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Retrieval of LIDAR Aerosol Parameter Using Sun/Sky Radiometer at Gangneung, Korea

  • Shin, Sung-Kyun;Lee, Kwon-Ho;Lee, Kyu-Tae
    • Current Optics and Photonics
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    • v.1 no.3
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    • pp.175-185
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    • 2017
  • The aerosol optical properties such as depolarization ratio (${\delta}$) and aerosol extinction-to-backscatter ratios (S, LIDAR ratio) and ${\AA}ngstr{\ddot{o}m$ exponent (${\AA}$) derived from measurement with AERONET sun/sky radiometer at Gangneung-Wonju National University (GWNU), Gangneung, Korea ($37.77^{\circ}N$, $128.87^{\circ}E$) during a winter season (December 2014 - February 2015) are presented. The PM concentration measurements are conducted simultaneously and used to identify the high-PM events. The observation period was divided into three cases according to the PM concentrations. We analysed the ${\delta}$, S, and ${\AA}$ during these high PM-events. These aerosol optical properties are calculated by the sun/sky radiometer data and used to classify a type of aerosols (e.g., dust, anthropogenic pollution). The higher values of ${\delta}$ with lower values of S and ${\AA}$ were measured for the dust particles. The mean values of ${\delta}$, S, and ${\AA}$ at 440-870 nm wavelength pair (${\AA}_{440-870}$) for the Asia dust were 0.19-0.24, 36-56 sr, and 0.48, respectively. The anthropogenic aerosol plumes are distinguished with the lower values of ${\delta}$ and higher values of ${\AA}$. The mean values of spectral ${\delta}$ and ${\AA}_{440-870}$ for this case varied 0.06-0.16 and 1.33-1.39, respectively. We found that aerosol columnar optical properties obtained from the sun/sky radiometer measurement are useful to identify the aerosol type. Moreover, the columnar aerosol optical properties calculated based on sun/sky radiometer measurements such as ${\delta}$, S, and ${\AA}$ will be further used for the validation of aerosol parameters obtained from LIDAR observation as well as for quantification of the air quality.

Effects of Egg Shell Membrane Hydrolysates on UVB-radiation-induced Wrinkle Formation in SKH-1 Hairless Mice

  • Yoo, Jin Hee;Kim, Jong Keun;Yang, Hee Jin;Park, Ki Moon
    • Food Science of Animal Resources
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    • v.35 no.1
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    • pp.58-70
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    • 2015
  • This study was conducted to examine the effect of egg shell membrane hydrolysates (ESMH) on wrinkle, UV, and moisture protection for cosmetic use. ESMH were fragmented as whole ESMH (before fractioning), Fraction I (> 10 kDa), Fraction II (3-10 kDa), and Fraction III (< 3 kDa). In order to test whether fractionated ESMH can be used for functional cosmetic materials, we examined not only the level of hyaluronic acid and collagen production, but also the MMP-1 activity using a HaCaT and CCD-986Sk cell line. Our study treated each sample of fractionated ESMH with different concentrations (0.01, 0.1, 1 mg/mL). In our in vivo research, we used hairless mice that had been exposed to UV-B to induce wrinkles for 7 wk, then applied Fraction I to the treatment group for 5 wk and then tested skin thickness, minimum erythema dose and moisture content. In addition, Fraction I was high in collagen and HA biosynthesis and it was better than TGF-${\beta}$ in improving of the skin. When TNF-${\alpha}$ caused MMP-1 activity in the CCD-986Sk cells, the whole ESMH and Fraction I proved to be effective in hindering the induction of collagenase depending on the concentration, and also showed outstanding effects in the suppression of skin aging. We found that the treatment group mice's UV-B radiation-induced skin damage was largely mitigated compared to that of the non-treatment group mice. Thus, we have concluded that EMSH helps to mitigate UV-B radiation-induced wrinkles, collagen, HA, MMP-1 activity and can be used for functional cosmetic materials.

Analysis of Radiolytic Products of Lipid for the Detection of Irradiated Dried Cuttle Fish (Sepia officinalis) (건 갑오징어의 방사선 조사여부를 판별하기 위한 지방분해산물 분석)

  • Kim, Jun-Hyoung;Kim, Kyoung-Su
    • Korean Journal of Food Science and Technology
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    • v.35 no.6
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    • pp.1072-1078
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    • 2003
  • Radiation-induced hydrocarbons and 2-alkylcycolbutanones are formed from the fatty acids of irradiated fat. These radiation-induced compunds were detected by fat extraction with a Soxtec apparatus from dried cuttle fish (Sepia officinalis), isolation of hydrocarbons and 2-alkylcyclobutanones with florisil column chromatography, and identification of GC/MS. Concentration of hydrocarbons produced by -λ-irradiation depended on the composition of fatty acid in dried cuttle fish. The major hydrocarbons in the irradiated dried cuttle fish samples were pentadecane and 1-tetradecene from palmitic acid, heptadecane and 1-hexadecene from stearic acid, and 8-heptadecen and 1,7-hexadecadiene from oleic acid. Of 2-alkylcyclobutanones, 2-dodecylcyclobutanone from palmitic acid was present at the highest level in irradiated dried cuttle fish. The radiation-induced hydrocarbons and 2-alkylcyclobutanones from the irradiated dried cuttle fish were detected at 0.5 kGy and over, but not detected in the non-irradiated fish.

Alarm Setpoint Determination Method of Gaseous Effluent Radiation Monitoring Systems Using Dose Factors Based on ICRP-60 Recommendations (선량환산인자를 이용한 기체유출물 RMS 경보설정 개선방안)

  • 박규준;김희근;하각현;엄희문
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2003.11a
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    • pp.491-496
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    • 2003
  • In Korea, the dose limits to the public were reduced according to ICRP-60 recommendations. The secondary quantities, Effluent Concentration Limits (ECLs) were derived and enacted to Korean Atomic Laws based on ICRP-60 recommendations. The Korea atomic laws require assurance that radioactive materials within gaseous effluents do not exceed dose limits and ECLs. This simply means that any effluent that would possibly contain radioactivity must be monitored. There are various methods to monitor the radioactivity of effluent monitor to satisfy the dose limits and the ECLs for gaseous effluents. The many factors (safety margin) should be considered in determining of the setpoint of effluent monitor, following these limits. In this study, we studied the determination method of alarm setpoint for gaseous effluent Radiation Monitoring Systems using dose factors considered the main pathway of radionuclides to compare the preceding determination method of alarm setpoint for gaseous effluent RMSs using dose assessment program considered all the practicable pathways of radionuclides.

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Fabrication and $^{60}Co$ Gamma Induced Damage of Plastic Scintillators (플라스틱 섬광체의 제작과 $^{60}Co$ $\gamma$-선에 의한 방사선 손상)

  • Kim, Sung-Hwan;Nam, Seung-Hee;Cheon, Jong-Kyu;Kim, Wan;Kang, Hee-Dong;Kim, Do-Sung;Lee, Woo-Gyo;Doh, Sih-Hong
    • Journal of Sensor Science and Technology
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    • v.9 no.5
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    • pp.350-356
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    • 2000
  • The optimum composition ratios of primary solute(p-terphenyl) and secondary solute(popop) have been investigated in order to fabricate plastic scintillator with higher light output and less radiation damage. The radiation damage induced by $^{60}Co$ $\gamma$-irradiation depends on mainly the concentration of secondary solute. The spectral range of the luminescence was $400{\sim}450\;nm$, its peak emission appeared at 415 nm. The transmittance and the light output were not changed by radiation damage up to $1{\times}10^4\;Gy$ irradiation with $^{60}Co$ $\gamma$-rays.

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Catalase Induced by All-Trans Retinoic Acid Is Involved in Antiproliferation of 36B10 Cells (레티노인산에 의한 카타라제의 유도가 36B10세포의 증식억제에 미치는 효과)

  • Park, Woo-Yoon;Yu, Jae-Ran
    • Radiation Oncology Journal
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    • v.28 no.4
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    • pp.211-218
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    • 2010
  • Purpose: All-trans retinoic acid (ATRA) has anti proliferative effects against brain tumor cells. Recently, ATRA has been reported to induce catalase. We investigated whether catalase induction by ATRA is associated with its anti proliferative effects. Materials and Methods: 36B10 cells were exposed to 0~50${\mu}M$ ATRA for 24 or 48 hours and mRNA, protein, and activity of catalase were measured. Reactive oxygen species (ROS) were measured using 2',7'-dichlorofluorescin diacetate. A clonogenic assay was used to confirm the cytotoxic effect. Results: The mRNA, protein, and activity of catalase were found to increase in a concentration- and incubationtime-dependent manner. The increase in catalase activity induced by ATRA was decreased by the addition of 3-amino-1,2,4-triazole (ATZ). ROS was also increased with ATRA and decreased by the addition of ATZ. The decrease in cell survival induced by ATRA was partly rescued by ATZ. Conclusion: Catalase induction by ATRA is involved in ROS overproduction and thus inhibits the proliferation of 36B10 cells.

Korean Red Ginseng saponin fraction modulates radiation effects on lipopolysaccharide-stimulated nitric oxide production in RAW264.7 macrophage cells

  • Lee, Young Ji;Han, Jeong Yoon;Lee, Chang Geun;Heo, Kyu;Park, Se Il;Park, Yoo Soo;Kim, Joong Sun;Yang, Kwang Mo;Lee, Ki-Ja;Kim, Tae-Hwan;Rhee, Man Hee;Kim, Sung Dae
    • Journal of Ginseng Research
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    • v.38 no.3
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    • pp.208-214
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    • 2014
  • Background: In previous work, we reported that Korean Red Ginseng saponin fraction (RGSF) showed anti-inflammatory activities in vitro and in vivo. Methods: The present study investigated the radioprotective properties of RGSF by examining its effects on ionizing radiation (IR)-enhanced and lipopolysaccharide (LPS)-mediated inflammatory responses in murine macrophage cells. Results: RGSF induced strong downregulation of IR-enhanced and LPS-induced proinflammatory responses such as nitric oxide (NO) production (Inhibitory Concentration $50(IC_{50})=5.1{\pm}0.8{\mu}M$) and interleukin-$1{\beta}$ levels. RGSF was found to exert its radioprotective effects by inhibition of a signaling cascade that activated checkpoint kinase 2enuclear factor-${\kappa}B$. In addition, RGSF strongly inhibited IR-enhanced LPS-induced expression of hemoxyganase-1, implying that the latter may be a potential target of RGSF. Conclusion: Taken together, our data suggest that RGSF can be considered and developed for use as an effective radioprotective agent with minimal adverse effects.

Distribution of 90Sr Activities in the Environmental Radiation Samples of Jeju Island, Korea

  • Han, Chung Hun;Park, Youn Hyun;Lee, Young Gyu;Park, Jae Woo
    • Journal of Radiation Protection and Research
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    • v.41 no.4
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    • pp.418-423
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    • 2016
  • Background: This work was to get information about $^{90}Sr$ contamination of the environment by using soil and moss from selected areas in Jeju Island, Korea. Materials and Methods: The activities of $^{90}Sr$ in soil and moss samples were investigated at nine locations of Jeju island, Korea. The soil samples have been collected at 4 sites of Jeju island during June to August of 2013, analyzed for vertical distribution of $^{90}Sr$ activities. The moss samples have been collected at 5 sites of Jeju island during November of 2011 to June of 2012, and analyzed for radioactive $^{90}Sr$. Results and Discussion: The $^{90}Sr$ vertical concentrations in the investigated soil samples were 2.77 to $18.24Bq{\cdot}kg^{-1}$ in eastern part, 1.69 to $18.27Bq{\cdot}kg^{-1}$ in northern part, 3.76 to $13.46Bq{\cdot}kg^{-1}$ in the western part and 1.09 to $8.70Bq{\cdot}kg^{-1}$ in the southern part of the Mt. Halla in Jeju island, respectively. Activities of $^{90}Sr$ show the highest value at the surface soil and decrease with depth. The activity concentration measured was in the range of 79.6 to $363Bq{\cdot}kg^{-1}$ -dry moss. Conclusion: This material is expected to be basis reference for survey of environmental radioactivity in Jeju Island.

The Anti-melanogenic Effect of Whitening Agent Containing Arbutin and ${\beta}-Glucosidase$ (알부틴과 베타-글루코시다제를 함유하는 미백 화장품의 항멜라닌 효과)

  • Lew Bark-Lin;Ryou Ji-Ho;Lee Mu-Hyoung
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.30 no.3 s.47
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    • pp.415-418
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    • 2004
  • Arbutin is a glycosylated hydroquinone found at high concentration in certain plants capable of surviving extreme and sustained dehydration. It has been reported to have an inhibitory effect of melanogenesis and to be hydrolyzed easily to yield glucose and hydroquinone by ${\beta}-glucosidase.$ While hydroquinone also has an anti-melanogenic effect, however, is carefully used as a topical whitening agent because of side effects. The present study was undertaken to examine the inhibitory effect of an whitening agent containing arbutin and ${\beta}-glucosidase$ on UV radiation induced pigmentation in human skin. Experimental subjects were UVB-irradiated on the back. UVB-irradiated areas were assigned to three groups: arbutin and ${\beta}-glucosidase$ treated group, vehicle control, and no-application control. Arbutin and ${\beta}-glucosidase$ treatment inhibited pigmentation by 50.17 percent, compared with the controls (N : 10: P<0.05). These results suggest that the whitening agent containing arbutin and ${\beta}-glucosidase$may be used as an agent to inhibit melanin formation induced by UV radiation.

Formation of Ultra fine Particle by the Polonium-218 Ions under Different Humidity Conditions (다른 습도조건하에서 Po-218 이온들의 극소입자형성에 관한 연구)

  • Yoon, Suk-Chul;Ha, Chung-Woo
    • Journal of Radiation Protection and Research
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    • v.17 no.1
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    • pp.1-10
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    • 1992
  • A number of investigators have reported the formation of the radiolytic ultrafine particles produced by the interaction of ionizing radiation with water vapor. Previous studies have suggested that a very high localized concentration of the OH radical produced by the radiolysis of water can react with trace gas like organic vapors and produce lower vapor pressure compounds that can then nucleate. In order to determine water vapor dependence of the active, positively charged, first radon daughter(Po-218), an experiment was conducted using a well-controlled radon chamber. The activity size distribution of the radon daughter in the range of 0.5-100nm was measured using the parallel graded wire screens system. Measurements were taken for different relative humidity. The resultant activity size distributions were analyzed. The addition of water vapor to the radon carrier gases resulted in the formation of ultrafine particles by OH radicals formed by radon radiolysis. It may be due to the neutralization of charged Po-218 ion with water vapor through the radio lysis.

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