• Imaging Science in Dentistry
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• v.36 no.4
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• pp.189-198
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• 2006

Purpose: To investigate the in vitro response of MC3T3-E1 osteoblastic cells to X-ray in the presence and absence of 2 deoxy-D-glucose (2-DG) and quercetin (QCT). Materials and Methods: The MC3T3-E1 cells were cultured in an ${\alpha}-MEM$ supplemented with 5 mM 2-DG or $10{\mu}M$ QCT and then the cells were incubated for 12 h prior to irradiation with 2, 4, 6, and 8Gy using a linear accelerator (Mevaprimus, Germany) delivered at a rate of 1.5 Gy/min. At various times after the irradiation, the cells were processed for the analyses of proliferation, viability, cytotoxicity, and mineralization. Results: Exposure of the cells to X-ray inhibited the tritium incorporation, 3-(4, 5-dimethylthiazol-2yl-)-2, 5-diphenyl tetrazolium bromide (MTT)-reducing activity, and alkaline phosphatase (ALP) activity, and caused cytotoxicity and apoptosis in a dose-dependent manner of the X-ray. This effect was further apparent on day 3 and 7 after the irradiation. RA+2-DG showed the decrease of DNA content, cell viability, and increase of cytotoxicity rather than RA. ALP activity increased on day 7 and subsequently its activity dropped to a lower level. 2-DG suppressed the calcium concentration, but visual difference of number of calcified nodules between RA and RA+2-DG was not noticed. RA+QCT showed the increase of DNA content, cell viability, but decrease of cytotoxicity and subG1 stage cells in the cell cycle, and increased calcified nodules in von Kossa staining rather than the RA. ALP activity showed significant increases on day 7 and subsequently its activity dropped to a lower level. Conclusion: The results showed that the 2-DG acted as a radiosensitizing agent and QCT acted as a radiosensitizing agent respectively in the irradiated MC3T3-E1 osteoblast-like cells.

• Economic and Environmental Geology
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• v.32 no.5
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• pp.469-483
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• 1999

Two different types of deep groundwaters occur together in the Jungwon area: $CO_2$-rich water and alkali water. Each water shows distrinct hydrogeochemical and environmental isotopic characteristics. The $CO_2$-rich waters are characterized by lower pH(6.0~6.4), higher Eh (25~85mV) and higher TDS content (up to 3,300 mg/l), whereas the alkali type waters have higher pH (9.1~9.5), lower Eh (-136~-128mV) and lower TDS content (168~254 mg/l). The CO2-rich waters ($Pco_2$=up to 1atm) were probably evolved by the local supply of deep $CO_2$ during the deep circulation, resulting in enhanced dissolution of surrounding rocks to yield high concentrations of $Ca^{2+}, Na^+, Mg^{2+}, K^+\; and \;HCO_3\;^-$ under low pH conditions. On the other hand, the alkali type waters ($Pco_2$=about 10-4.6 atm) were evolved through lesser degrees of simple wate/rock (granite) interaction under the limited suppy of $CO_2$. The alkali waters are relatively enriched in F- (up to 14mg/l), whereas the F- concentration of$CO_2$-rich water is lower (2.2~4.8 mg/l) due to the buffering by precipitation of fluorite. The oxygen-hydrogen isotopes and tritium data indicate that compared to shaltion ($\delta$18O=-9.5~-7.8$\textperthousand$),two different types fo deep groudwaters (<1.0TU)were both derived from pre-thermonuclear (more than 40 years old) meteoric waters with lighter O-H isotopic composition ($\delta$18O=-9.5~-7.8$\textperthousand$) and have evolved through prolonged water/rock interaction. The $CO_2$-rich waters also show some degrees of isotopic re-equilibration with $CO_2$ gas. The $\delta^{34}S$ values of dissolved sulfates (+24.2~+27.6$\textperthousand$) in the $CO_2$-rich waters suggest the reduction of sulfate by organic activity at depths. The carbon isotope data show that dissolved carbon in the $CO_2$-rich waters were possibly derived either from dissolution of calcite or from deep $CO_2$ gas. However, strontium isotope data indicate Ca in the $CO_2$-rich waters were derived mainly from plagioclase in granite, not from hydrothermal calcites.

• The Journal of Engineering Geology
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• v.10 no.1
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• pp.51-62
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• 2000

The $CO_2$-richrich water pumps or springs out at two sites (Sinchon and Kohran) consisting of Cretaceous sedimentary rocks in Kyungpook area. The water has been long known as its soda pop-liketaste and therapeutic effect against calcium deficit, stomach and skin troubles, etc. The water arecharacterized by a high $CO_2$ concentration $(P_{CO2}=0.29~l.01 atm)$ and electrical conductance (1,093~2,810$\mu$S/cm). The $CO_2$-rich water belongs to Ca(Na)-$HCO_3$ type in chemical classification. The contents of Ca, Mg, Na, HCO$_3$ and Fe of $CO_2$-rich water show much higher values than those of general groundwater Environmental isotopic data $(^2H/^1H, ^{18}O/^{16}O and ^3H/^1H)$ indicate that the water is ofmeteoric origin recharged after 1950s. The $CO_2$ in the springs seems to be originated from deep-seatedsource related to acidic porphyry and granite nearby sedimentary rocks. Carbonate minerals and albiteare likely to be the major source minerals of the dissoved inorganic constituents in the $CO_2$-rich water.The equilibrium state between major minerals and $CO_2$-rich water was calculated by a thermodynamicprogram.

• Journal of the Korean Society of Radiology
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• v.14 no.7
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• pp.857-862
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• 2020

In March 2011, a tsunami off Japan caused radioactive material that had seeped into the sea from the Fukushima nuclear accident to flow to the Pacific Ocean, causing pollution to sea life. For a comparative evaluation with the area surrounding the site of a nuclear power plant by the release of radioactive materials, an area 20 to 30 km away from the emergency protection plan area was selected as a comparative point considering weather conditions, population distribution, etc. In addition, the government intends to analyze the minimum detection radiation received by residents around the nuclear power plant and evaluate the effective dose. Analysis of tritium radiation from water samples showed that most of the samples were not detected and that 0.0014 % to 0.777 % of the annual legal standard of 1 mSv for the general public had little effect on the human body. Therefore, the measurement and analysis of water samples around the nuclear power plant site is expected to help relieve anxiety, such as exposure to the general public and neighboring residents due to radiation release.