• Environmental Engineering Research
• /
• v.21 no.2
• /
• pp.164-170
• /
• 2016

Since most of the existing wastewater treatment options lack the ability to treat micro-contaminants, the increased use of pharmaceuticals and personal care products (PPCPs) and release as human waste have become a serious concern in recent years. Constructed wetlands (CWs) are a low-cost technology for wastewater treatment, however, its performance in term of PPCPs removal has not yet been fully investigated. This study aimed to characterize the removal factors and efficiency of acetaminophen (ACT) removal by CWs. The results revealed the decreased concentrations of ACT with increasing hydraulic retention times (HRT) of 0, 3, 5 days. The contribution of removal factors was found to be varied with initial ACT concentration. At the low ACT concentration (i.e. 1 ppb), plant uptake was the dominant, followed by microbial and photolytic removal. In contrast, at the high ACT concentration (i.e. 100 ppb), microbial and photolytic removal were found as dominant factors. On the other hand, hydrogen peroxide ($H_2O_2$) concentration was found at higher level in the plant shoot than in the root probably due to occurrence of the Fenton reaction resulting in PPCPs removal.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.5
• /
• pp.1177-1181
• /
• 2010

The synthesis and characterization of gold nanoparticles coated by Gd-chelate (GdL@Au) is described, where L is a conjugate of DTPA (DTPA = diethylenetriamine-N,N,N',N",N"-pentaacetic acid) and 4-aminothiophenol. These particles are obtained by the replacement of citrate from the gold nanoparticle surfaces with gadolinium chelate (GdL). The average size of GdL@Au is 12 nm with a loading of GdL reaching up to $1.4{\times}10^3$ per particles, and they demonstrate very high r1 relaxivity (${\sim}10^4mM^{-1}s^{-1}$) and the r1 relaxivity per [Gd] is as high as $10mM^{-1}s{-1}$. Here, we also describe the use of bimodality of this contrast agent (CA) as a highly efficient CT contrast agent based on gold nanoparticles (GNPs) that overcome the limitations of iodine based contrast agent. The MTT assay performed on this CAs reveals the cytotoxicity as low as that for Omniscan$^{(R)}$ in the concentration range required to obtain intensity enhancement in the in vivo MRI study.

• Korean Journal of Environmental Biology
• /
• v.22 no.3
• /
• pp.405-410
• /
• 2004

The effect of treatment with Citrus junos fractions (citron 3W, citron 3H, citron 4W and citron 4H) upon rat hepatocytes exposed to alcohol was investigated. We compared the serum biochemistry of rats administered both alcohol and Citrus junos fractions to control rats treated with alcohol alone. The effects of Alanine amino transferase (ALT) were significantly lower in the citron 3H extract group compared with the negative control group (p<0.05) and other experimental groups were not significantly low but a little low compared to negative control group. The levels of triglyceride (TG) were significantly low in all experimental groups compared with negative control group. Especially triglyceride level of citron 3H was lowest near to normal control group. The concentration of total cholesterol was significantly high in negative groups compared with normal control group but in all experimental groups, the concentration of total cholesterol was similar to that of negative control group. Total cholesterol of the citron 4W group was somewhat low compared with negative control group. In contrast, activities of alcohol dehydrogenase (ADH) were significantly higher in all experimental groups compared with the negative control (p<0.05) group. These data suggest that Citrus junos fractions may represents an excellent candidate for protection of rat hepatocytes from alcohol-mediated damage.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.12 no.8
• /
• pp.3572-3578
• /
• 2011

In Positron Emission Tomography Computed Tomography, Standardized Uptake Value(SUV)is most generally used to discern tumors. However, SUV may be influenced other factors. In this study, experiment was conducted distrotion in image and change in SUV according to substance with GEMINI TF PET/CT of Philips.. SUV for materials resulted in 1.8 for stainless, 1.4 for stent, 2.4 for iodine contrast medium, 2.6 for Barium Sulfate, 1.6 for Gypsum, and 1.4 for paraffin respectively. The distortion of image was remarkable for the iodine contrast medium and Barium Sulfate. For the barium sulfate, the higher the density, the larger the distrotion of the images. As a result of test, it appeared that the metallic substance whose atomic number is low and contrast medium whose concentration is low didn't affect the distortion in image and the change in SUV. However, it tis necessary to minimize distortion in image and change in SUV, by removing the metallic substance and checking if there are contrast mdeium or before examination.

• YAKHAK HOEJI
• /
• v.23 no.3_4
• /
• pp.173-179
• /
• 1979

A dose, 1g/kg of ethanol produced experimental hyperuricemia in mouse. Ginseng saponins were tested for their ability to alter the hepatic xanthine oxidase activity and the blood level of uric acid in the ethanol-treated mouse. Intraperitoneal injection of ginseng saponin 4mg/kg markedly decreased the xanthine oxidase activity in the ethanol-treated mouse liver. It was also observed that ginseng saponin reduced the blood concentration of uric acid in experimentally induced hyperuricemia by alcohol treatment. In vitro, it was found that a low concentration of ginseng saponin in the reaction mixture incresed the hepatic xanthine oxidase activity, while a high concentration inhibited both enzyme preparations of normal and ethanol treated mice. In contrast with the xanthine oxidase, uricase activity was not influenced by ginseng saponin as well as in vivo. These results suggest there is a possibility that ginseng saponin may have some therapeutic effect on gout and other hyperuricemia syndrome.

• Journal of the Korean Society of Radiology
• /
• v.9 no.1
• /
• pp.47-53
• /
• 2015

Quantitative analysis of MR spectrum depending on mole concentration of the contrast media in cereberal metabolite phantom was performed. PRESS pulse sequence was used to obtain MR spectrum at 3.0T MRI system (Archieva, Philips Healthcare, Best, Netherland), and the phantom contains brain metabolites such as N-Acetyl Asparatate (NAA), Choline (Cho), Creatine (Cr) and Lactate (Lac). In this study, optimization of MRS PRESS pulse sequency depending on the concentration of contrast media (0, 0.1 and $0.3mmol/{\ell}$) was evaluated for various repetition time(TR; 1500, 1700 and 2000 ms). In control (cotrast-media-free) group, NAA and Cho signals were the highest at TR 2000 ms than at 1700 and 1500 ms. Cr had the highest peak signal at TR 1500 ms. When concentration of contrast media was $0.1mmol/{\ell}$, the metabolites were increased NAA 73%, Cho 249%, Cr 37% at TR 1700 ms compared with other TR, and also signal increased at $0.3mmol/{\ell}$, In $0.5mmol/{\ell}$ of contrast agent, cerebral metabolite peaks reduced, especially when TR 1500 ms and 2000 ms they decreased below those of control group. The ratio of metabolite peaks such as NAA/Cr and Cho/Cr decreased as the concentration of the contrast agent increased from 0.1 to $0.5mmol/{\ell}$. Authors found that the optimization of PRESS sequence for 0.3T MRS was as follows: low density of contrast agent ($0.1mmol/{\ell}$ and $0.3mmol/{\ell}$) made the highest signal intensity, while high density of contrast agent reveals the least reduction of signal intensity at 1700 ms. In conclusion, authors believe that it is helpful to reduce TR for acquiring maximum signal intensity.

• Journal of Environmental Science International
• /
• v.26 no.1
• /
• pp.55-65
• /
• 2017

Average concentration of PM in Seoul metropolitan area satisfied the Korean air quality standard in 2010. Furthermore, concentration of PM in all boroughs across Seoul met the air environment standard in 2012. $PM_{10}$ concentration was relatively higher in center of Seoul in comparison to the rest, while $PM_{2.5}$ concentration showed exactly the contrary result. We analyzed the effect that PM emissions from vehicles would have on PM concentrations across Seoul. The results showed that average annual PM concentration recently decreased in Seoul although the number of vehicles registered annually continued its upward trend. By contrast, average fine dust concentrations in Seoul showed a decline which suggested that correlation between annual average PM concentrations and number of registered vehicles remained low. However, year-on-year vehicle registration rate recently showed a declining tendency in the same way as the trend of changes in average PM concentrations. Particularly, the upward trend in annual average PM concentrations in 2002 and 2007 was consistent with the increase in vehicle registration rate, suggesting that vehicle registration rate was closely associated with changes in PM concentrations.

• Environmental Analysis Health and Toxicology
• /
• v.9 no.1_2
• /
• pp.9-17
• /
• 1994

The Ha-antagonist, cimetidine, has been shown to retard the hepatic elimination of low and high clearance drugs, and this has been attributed to inhibition of microsomal cytochrome P-450. This study was done to determine the effects of low (50$\mu\textrm{g}$) and high (1mg) dose of famotidine, another histamine H$_2$-receptor antagonist, on hepatic elimination of propranolol compared with cimetidine in the isolated perfused rat liver. Both low and high dose of cimetidine not only inhibited the elimination of propranolol but also increased the area under the perfusate propranolol concentration time curve (AUC). In contrast, low and high dose of famotidine did not affect hepatic elimination of propranolol. Our findings suggest that famotidine has not a propensity for hepatic microsomal inhibition.

• Journal of Korean Ophthalmic Optics Society
• /
• v.20 no.3
• /
• pp.355-362
• /
• 2015

Purpose: To investigate the effects of the transmittance of diffusive blurson visual acuity and contrast sensitivity. Methods: Visual acuity and contrast sensitivity were measured by using Optec$^{(R)}$ 6500 in Healthy 30 subjects aged $22.83{\pm}0.50$ (male 13, female 17) who were recruited from university students. Cataract simulator was used as a tool for diffusive blur. Visual acuity and contrast sensitivity were measured with varying the transmittance of diffusive blur in order to simulate progression of cataract and concentration in fog. Results: Visual acuity was reduced proportionally with decreasing the transmittance of the diffusive blur as follows: $VA(T)=1.84{\times}10^{-2}T-0.645$. Contrast sensitivity was decreased in all spatial frequencies. Contrast sensitivity in a high spatial frequency band was a greater effect and was off the normal range of contrast sensitivity. The peak of contrast sensitivity was moved in the direction to low frequency. From an intersection point of contrast sensitivity function, we could calculated the transmittance of the diffusive blur being off the normal range and the shift to peak spatial frequency. The peak of contrast sensitivity function was observed to move from 6 to 3 cpd at transmittance of about 78.70%, the contrast sensitivities for all frequencies at transmittance of about 69.71% were deviated from the normal range. Conclusions: The transmittance of diffusive blur causes a reduction in visual acuity and contrast sensitivity, a deviation of normal range of contrast sensitivity, and a shift of peak contrast sensitivity. Therefore the more attention is required when suffering from cataracts or driving in fog.

• Journal of Environmental Science International
• /
• v.17 no.1
• /
• pp.97-105
• /
• 2008

This study examined the contaminated soils with an indicator of TPH using SVE (Soil Vapor Extraction) and biological treatments. Their results are as follows. Water content in the polluted soils slowly decreased from 15% during the initial experimental condition to 10% during the final condition. Purification of polluted soils by Bioventing system is likely to hinder the microbial activity due to decrease of water content. Removal rate of TPH in the upper reaction chamber was a half of initial removal rate at the 25th day of the experiment. The removal rate in the lower reaction chamber was 45% with concentration of 995.4 mg/kg. When the Bioventing is used the removal rate at the 14th day of the experiment was 53%, showing 7 day shortenting. Since the Bioventing method control the microbial activity due to dewatering of the polluted soil, SVE method is likely to be preferable to remove in-situ TPH. The reactor that included microbes and nutrients showed somewhat higher removal rate of TPH than the reactor that included nurtients only during experimental period. In general, the concentration showed two times peaks and then decreased, followed by slight variation of the concentration in low concentration levels. Hence, in contrast to SVE treatment, the biological treatment tend to show continuous repetitive peaks of concentration followed by concentration decrease.