• Journal of Environmental Science International
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• v.23 no.8
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• pp.1419-1428
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• 2014

Electron beam-induced grafting polymerization was employed to prepare Acrylic acid-grafted bacterial cellulose (BC-g-AAc). BC-g-AAc as an adsorbent was applied to remove heavy metals (e.g., As, Pb, and Cd). This study examined followings; morphological change of surface, adsorptive behavior of BC-g-AAc, and interpretation of adsorptive kinetics. Specific surface areas of BC and BC-g-AAc were $0.9527m^2g^{-1}$ for BC and $0.2272m^2g^{-1}$ for BC-g-AAc, respectively as measured by BET nitrogen adsorption, revealing the morphological change of the surface of BC-g-AAc. Batch adsorption test was performed to investigate adsorptive behavior of BC-g-AAc in aqueous solution. The amounts of Pb and Cd adsorbed on BC-g-AAc were $69mg\;g^{-1}$ and $56mg\;g^{-1}$, respectively. However, As was not adsorbed on BC-g-AAc due to its neutral nature. Both the Benaissa model and the Kurniawan model were applied in the study to interpret adsorptive kinetics. From the value of correction coefficient ($R^2$), adsorptive kinetics of Pb and Cd were subjected to Kurniawan model referred to pseudo-second-order. Taken together, the results of this study show that BC-g-AAc has potential as a heavy metal (eg., Pb, Cd)-adsorbent made of an environmentally friendly material.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.2
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• pp.132-136
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• 2020

Purpose: To evaluate the effect of gluten-free diet (GFD) on hepatitis B surface antibody (HBsAb) concentrations among previously immunized pediatric celiac disease (CD) subjects. Methods: We retrospectively evaluated pediatric CD subjects in serological remission who were previously immunized for hepatitis B virus as infants. The temporal relationship between HBsAb concentration, the amount of time on a GFD, and age were evaluated. Results: Overall, 373 CD subjects were analyzed: 156 with HBsAb sampled prior to GFD initiation and 217 after initiation of a GFD and in serological remission. Median age at HBsAb concentration measurement for those before and after GFD initiation was 5.3 years (interquartile range [IQR], 3.1-9.2 years) and 7.6 years (IQR, 5.4-10.9 years), respectively (p<0.001). There was no sex difference between the groups. The median time of HBsAb measurement was 2 months (IQR, 0-5.7 months) before and 12.8 months (IQR, 5.3-30.3 months) after initiation of GFD. The HBsAb concentration was low in 79 (50.6%) and 121 (55.7%) subjects before and after GFD initiation, respectively (p=0.350). Age was inversely associated with low HBsAb concentrations. Neither being on a GFD nor sex was associated with low HBsAb concentrations. Conclusion: Adherence to a GFD does not affect HBsAb concentration in children with CD. Age is inversely associated with HBsAb concentration.

• Analytical Science and Technology
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• v.23 no.1
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• pp.74-82
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• 2010

As a basic research for development of the domestic portable XRF spectrometer, we discussed the analytical results of bench-top and portable XRF methods for RoHS materials of the Cd, Pb, Hg, Cr(IV), polybrominated biphenyls(PBB) and polybrominated diphenyl ehters(PBDE). The instrumental parameters such as measurement time of bench-top and portable XRF were optimized using certified reference materials of polyethylene and polypropylene with 5 hazardous materials of 0~1,200 mg/kg. The quantitative analysis of total-Cr, total-Br, Cd, Hg and Pb in certified reference materials and plastic samples were compared by empirical method, fundamental parameter method of bench-top XRF and portable XRF.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.4
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• pp.341-347
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• 2013

This study presents the remote control of a board robot using a Sensing glove based on Bluetooth communication. The board robot is a kind of riding robot controlled by an user. The user wears the proposed remote glove controller, and changes a direction of the robot by different kinds of finger actions. Bluetooth is used for wireless communication between the board robot and its user. CdS cell Sensors and a LED in the glove are used for recognition of a number of finger actions, which are measured as analog signals. The finger actions have five commands ('1'right '2'neutrality '3'left '4'operation '5'stop), which are transmitted from the user to the board robot through Bluetooth communication. Experimental results show that proposed a Sensing glove can effectively control the board robot.

• Journal of Soil and Groundwater Environment
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• v.23 no.2
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• pp.30-39
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• 2018

Soil contamination survey was conducted during March - July, 2017 to obtain soil contamination profile of 16 organic and inorganic contaminants in Hanam industrial complex located in Gwangju, Korea. The concentrations of all surveyed contaminants except Cd showed were within 0.3~1.5 times of their natural background levels. Cd showed concentrations as high as 6.9 times of the background level, signifying the influence of the metal processing facilities in the complex. The concentrations of Zn, Pb and Hg in areas nearby industrial facilities were 1.3~5.5 times higher than those within the facility and green area. The concentration of Cu in the green area was 1.4~2.9 times higher than in other areas. The Soil Pollution Index (SPI) analysis revealed 54% of the total area belong to first-grade soil, 43% to second-grade, and 3% to third-grade. The Enrichment Factor (EF) of Zn, Pb, and Cd were 9.2, 15.6, and 88.5, respectively, indicating high accumulation and contamination of the soil with Cd.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1813-1818
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• 2006

We demonstrate a new approach to form gradient hole injection layer (HIL) in organic light-emitting diodes (OLEDs). Single spincoating of hole-injecting conducting polymer compositions with a perfluorinated ionomer results in gradient workfunction through the layer by self-organization, which lead to remarkably efficient single layer polymer light-emitting diodes (PLEDs) (${\sim}21$ cd/A). The device lifetime was significantly improved (${\sim50$ times) compared with the conventional hole injection layer, poly(3,4-ethylenedioxy-thiophene)/polystyrene sulfonate. This solution processed HIL also produced dramatically enhanced luminous efficiency (${\sim}34$ cd/A) in vacuum- deposited green fluorescent OLEDs while the vacuum deposited HIL gave the luminous efficiency of ${\sim}23$ cd/A in the same device structure.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.20-23
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• 2005

The objective of this study is to examine a stabilized efficiency of heavy metals including Cd, Cu, Pb and Zn using slaked lime. Tailings from the Janggun Pb-Zn mine, the second Yeonhwa Pb-Zn mine, the Jisi Au-Ag mine and the Sangdong W mine were sampled and measured heavy metal concentrations contents using AAS as various extraction methods. During 156 hours, column test were undertaken to evaluate the possibility of stabilization by slaked lime. The result shows that $Ca(OH)_2$ has a good efficiency in heavy metal stabilization, especially at the Jisi mine with stabilized efficiencies of 97%(Cd), 99%(Cu), 86%(Pb) and 99%(Zn), respectively.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.2
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• pp.169-176
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• 1999

The purpose of this study was to investigate the relationships of dietary nutrients and serum heavy metals in college women living Choong-Nam area of Korea. The mean age, height, weight, and BMI were 22.9years, 158.74cm, 53.39kg, and 21.71kg/$m^2$ respectively. The mean daily energy intake was 85.9% of RDA for Koreans. The ratio of energy from carbohydrate, fat, and protein was 61:23:16. And the daily vitamin A, B$_2$, Ca were 90%, 78%, 60% of RDA for Korea, respectively. The mean serum levels of Pb, Cd, Cr were 0.190, 0.005, 0.025$\mu\textrm{g}$/$m\ell$, respectively. The serum Cd was significantly different with dietary carbohydrate(p＜0.05). And the serum Cr was significantly different with dietary protein intake(p＜0.05), phosphorus(p＜0.01), potassium(p＜0.05). respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.157-158
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• 2006

$CdS_{0.69}Se_{0.31}$ single crystal grown by sublimation method. Hall effect measurement were carried out by the Van der Pauw method. The measurement values under the temperature were found to be carrier density $n\;=\;1.95\;{\times}\;10^{23}m^3$, Hall coefcient $RH\;=\;-3.21\;{\times}\;10^{-5}m^3/c$, conductivity ${\sigma}\;=\;362.41\;{\Omega}^{-1}m^{-1}$, and Hall mobility ${\mu}\;=\;1.16\;{\times}\;10^{-2}m^2/v.s$.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.23 no.4
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• pp.397-404
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• 2020

Purpose: Synbiotics can alleviate some intestinal pathologies or prevent trigger mechanisms for some diseases such as celiac disease (CD). If patients with high levels of anti-tissue transglutaminase (anti-tTG) immunoglobulin A (IgA) antibodies have normal duodenal histology, they are followed as potential CD patients. The aim of this study was to investigate the effect of synbiotic use on the blood levels of anti-tTG antibodies in children. Methods: Eighty-two patients with high anti-tTG levels were included in this study. Patients were randomly divided into two groups. The synbiotic group was treated with a daily dose of a synbiotic including multi-strain probiotics for 20 days. The control group was not administered any medication. Anti-tTG values at baseline and repeat measurements and the percentage change in anti-tTG levels between groups were compared. Results: The anti-tTG level at baseline was 36 U/mL (interquartile range [IQR], 26.4-68 U/mL) in the synbiotic group, and it decreased significantly to 13 U/mL (IQR, 6.5-27.5 U/mL) after 20 days (p<0.05). The anti-tTG level at baseline was 46 U/mL (IQR, 31-89 U/mL) in the control group, which also decreased significantly to 23 U/mL (IQR, 7-41 U/mL) after 20 days (p<0.05). Anti-tTG levels exhibited 73% and 56% decreases in the synbiotic and control groups, respectively (p<0.05). Conclusion: It may be speculated that a synbiotic supplementation can contribute to decreasing anti-tTG levels in children with potential CD.