• Journal of Korean Society of Environmental Engineers
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• v.28 no.6
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• pp.667-676
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• 2006

The reduction of $Hg^{2+}$ in the aqueous phase results in the production of dissolved gaseous mercury(DGM), and the volatilization of DGM has been identified as an important mechanism for the loss of Hg from waterbodies to the atmosphere. Although mercury emission in the world is known to be mostly from Asia, there have been few studies of measuring DGM concentrations in lakes in Asia. In this study, DGM concentrations were measured at Juam reservoir($35^{\cir}00'N,\;127^{\circ}14'E$), Korea. The results showed that the average concentrations of DGM at the upper and down stream of the lake during summer time were $95{\pm}8\;and\;130{\pm}15$ pg/L, respectively and the concentration of total mercury(TM) at the upper and down stream was $2.1{\pm}0.7,\;1.7{\pm}0.3$ ng/L respectively. Average DGM concentration during summer time($101{\pm}14pg/L$) was approximately 5.5 times higher than that during fall($18{\pm}0.1pg/L$). The DGM concentrations ai the midstream decreased from 32 to 13.7 pg/L during rain event, while the TM concentrations increased from 2.2 ng/L to 2.7 ng/L indicating the deposition of mercury from the atmosphere. Also, the diurnal patterns between DGM concentrations and UV intensities were observed. Water temperatures and DOC concentrations were significantly related to DGM concentrations, while TM concentrations were negatively related to DGM concentrations(p<0.0001). Comparing with the study of Dill et al.,(2006) the average concentrations of DGM $(109{\pm}15pg/L)\;and\;TM(2.2{\pm} 0.4ng/L)$ at Juam reservoir were approximately 3 and 2.2 times higher than those measured in other lakes(DGM: $38{\pm}16pg/L$, TM: $1.0{\pm}1.2ng/L$).

• Radiation Oncology Journal
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• v.23 no.1
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• pp.9-16
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• 2005

Purpose : To prospectively evaluate the use of positron emission tomography with the glucose analog fluoro-deoxyglucose (FDG-PET) to deoxyglucose (FDG-PET) to predict disease-free survival (DFS) after concurrent chemo-radiotherapy (CCRT) in patients with non-disseminated nasopharyngeal carcinoma (NPC). Materials and Methods : We studied 41 patients with non-disseminated NPC scheduled to undergo platinum-based CCRT were eligible for this study. Patients were studied by FDG-PET prior to the CCRT. FDG uptake of tumors were measured with the maximal standardized uptake value (SUV). Results : Complete response rate was $100\%$. In ten patients who presented with any component of treatment failure, the median $SUV_{max}$ was 8.55 (range: $2.49\~14.81$) in any component of failure and the median $SUV_{max}$ was 5.48 (range: $2.31\~26.07$) In the remaining patients without any such failure. Patients having tumors with high FDG uptake had a significantly lower 3-year DFS ($51\%\;{\nu}91\%$, p=0.0070) compared with patients having low uptake tumors. Conclusion : FDG uptake, as measured by the SUV, has potential value in predicting DFS in NPC treated by CCRT, High FDG uptake may be a useful parameter for Identifying patients requiring more aggressive treatment approaches.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.334-339
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• 2014

The purpose of our study was to investigate the migration level of lead (Pb), cadmium (Cd), antimony (Sb), arsenic (As), hexavalent chromium ($Cr^{6+}$) and mercury (Hg) from cookwares into food simulants and to evaluate the safety of each heavy metals. The test articles for heavy metals were glassware, ceramics, enamel, earthenware, polypropylene and polyethylene cookwares for Pb and Cd, enamel for Sb, earthenware for As, polyethylene and polypropylene cookwares for $Cr^{6+}$ and Hg. All the article samples of 391 intended for contact with foods were purchased in domestic markets. Pb, Cd, Sb and As were analyzed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES), $Cr^{6+}$ by UV visible spectrophotometer and Hg by mercury analyzer. The migration levels of heavy metals in all the samples were within the migration limits of Ministry of Food and Drug Safety (MFDS). As a result of safety evaluation, our results showed that the estimated daily intakes (EDI, mg/kg bw/day) were $9.12{\times}10^{-6}$ and $8.83{\times}10^{-7}$ for Pb and Cd from ceramics and $1.19{\times}10^{-5}$, $1.23{\times}10^{-5}$ and $7.52{\times}10^{-6}$ for Pb, Cd and Sb from enamel. Tolerable daily intakes (TDI, mg/kg bw/day) were established respectively as 0.0036, 0.00081, 0.0021, and 0.0006 for Pb, Cd, As and Hg by JECFA (Joint FAO/WHO Expert Committee on Food Additives), as 0.0060 for Sb by WHO (World Health Organization). When comparing with TDIs, the EDIs accounted for 0.25% and 0.11% for Pb and Cd from ceramics and 0.33%, 1.52% and 0.13% for Pb, Cd and Sb from enamel.