• Journal of Korean Society for Atmospheric Environment
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• v.29 no.1
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• pp.74-85
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• 2013

Since the underground transportation system is a closed environment, indoor air quality problems may seriously affect many passengers' health. The purpose of this study was to understand $PM_{10}$ characteristics in the underground air environment and further to quantitatively estimate $PM_{10}$ source contributions in a Seoul Metropolitan subway station. The $PM_{10}$ was intensively collected on various filters with $PM_{10}$ aerosol samplers to obtain sufficient samples for its chemical analysis. Sampling was carried out in the M station on the Line-4 from April 21 to 28, July 13 to 21, and October 11 to 19 in the year of 2010 and January 11 to 17 in the year of 2011. The aerosol filter samples were then analyzed for metals, water soluble ions, and carbon components. The 29 chemical species (OC1, OC2, OC3, OC4, CC, PC, EC, Ag, Al, Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Si, Ti, V, Zn, $Cl^-$, $NO_3{^-}$, $SO_4{^{2-}}$, $Na^+$, $NH_4{^+}$, $K^+$, $Mg^{2+}$, $Ca^{2+}$) were analyzed by using ICP-AES, IC, and TOR after proper pretreatments of each sample filter. Based on the chemical information, positive matrix factorization (PMF) model was applied to identify the $PM_{10}$ sources and then six sources such as biomass burning, outdoor, vehicle, soil and road dust, secondary aerosol, ferrous, and brakewear related source were classified. The contributions rate of their sources in tunnel are 4.0%, 5.8%, 1.6%, 17.9%, 13.8% and 56.9% in order.

• Microbiology and Biotechnology Letters
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• v.39 no.2
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• pp.140-145
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• 2011

Porcine epidemic diarrhea virus (PEDV) infection causes acute enteritis with lethal watery diarrhea resulting in a high mortality rate in piglets. As with the other members of group 1 coronaviruses, PEDV also utilizes the host aminopeptidase N (APN) as the major cellular receptor for entry into target cells. The coronavirus spike (S) protein is known to interact with the cellular surface for viral attachment and the S1 domain of all characterized coronaviruses contains a receptor-binding domain (RBD) that mediates a specific high-affinity interaction with their respective cellular receptors. Although the RBDs of several coronaviruses have been mapped, the location of the PEDV RBD has to date not been defined. As a first step toward the identification of the region of the S protein of the PEDV that is critical for recognition with the cellular receptor, we generated a series of S1-truncated variants and examined their abilities to bind to the porcine APN (pAPN) receptor. Our data indicate that the N-terminus of the S1 domain is required for pAPN association. The results from the present study may assist in our understanding of the molecular interactions between the PEDV S protein and the pAPN receptor.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.10
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• pp.1851-1859
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• 2000

Crude oil-degrading bacteria were isolated from the sites contaminated by oil products. The isolates were identified as Acinetobacter sp. A132, Pseudomonas putida A422, Pseudomonas aeruginosa F721, F722, and Xanthomonas maltophilia B823. The results of investigation on the degradability of crude oil indicated that the strain A132 had the highest rate of $6.04g/L{\cdot}day$. Also, the strain A132 and F722 almost degraded each of n-alkane compounds between $nC_{10}$ and $nC_{32}$. The strain A422 degraded benzene and xylene but not n-alkane. The strain B823 grew somewhat in crude oil but did not entirely degrade other substrates used in this study. The results of the GC/FID analysis on the degradability of the mixed n-alkane compounds showed that the strain F722 could degrade 100% of the compounds with $nC_7{\sim}nC_{10}$ and more than 80% of those with $nC_{11}{\sim}nC_{24}$.

• Journal of Environmental Health Sciences
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• v.43 no.3
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• pp.167-175
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• 2017

Objectives: Children may be more exposed to certain environmental contaminants because they react with greater sensitivity and have different food intakes and breathing rate per unit of body weight compared to adults. The aim of this study was to determine general exposure factors such as skin surface area, period and frequency of exposure, and others among Korean children aged ${\leq}18$ years old. This study was carried out as the first of its kind in Korea. Methods: We developed 23 recommended exposure factors for Korean children aged 0 to 18 years by reclassifying raw data from the National Health and Nutrition Examination Survey and the National Statistical Information Service, as well as through investigation by experiments in the absence of related data. Results: Reflecting the activity patterns of about 9,000 children, the daily inhalation rates for long-term exposure ranged from $9.49m^3/day$ for children from birth to <2 years to $14.98m^3/day$ for children aged 16 to <18 years. The research found that Korean children spent an average of 22.21 hours indoors, 0.67 hours outdoors, and 1.12 hours in-transit every day. Young children (${\leq}2$ years old) spent approximately 34 more minutes outdoors on weekends than they did on weekdays. Conclusion: Various physiological variables in the human body reflect characteristics of children that can directly influence risk exposure. Therefore, the identification of general exposure factors based on Korean children is required for appropriate risk assessment.

• Journal of the Korean earth science society
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• v.26 no.7
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• pp.630-639
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• 2005

The purpose of this study was to investigate the classifying ability of the igneous rocks with the naked eye for 36 preservice science teachers. For this, we selected six specimens of igneous rocks that consisted of rhyolite, andesite, basalt, granite, diorite, and gabbro, and performed the questionnaire with them. Preservice science teachers needed the average of 3 tools to classify the rocks. Most of the selected tools were loupe, streak plate, hammer and Mohs’ hardness scale. Many preservice science teachers selected basalt and granite samples to classify igneous rocks among 6 kinds of the rocks which were exhibited. However, the results of the identification with the naked eye showed that the right answer rate was significantly different based on what rock sample had been selected. Nobody gave the right answer among 10 students who chose the rhyolite sample, but all of 36 students who picked the basalt sample answered correctly. And $62\%$ of 8 students who chose the andesite sample, 62% of 32 student choosing granite, $7\%$ of 13 students choosing diorite and $44\%$ of 9 students choosing gabbro were correctly answered. In identifying igneous rock samples with the naked eye, most subjects relied on vesicular texture to basalt, and they used textural, color and empirical characters to granite. But, some felt more or less difficulty to distinguish between intermediate and light colors and to recognize porphyry.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.18 no.3
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• pp.187-192
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• 2015

Purpose: Measurement of serum ceruloplasmin level is the first step in screening for Wilson's disease (WD). Despite the rarity of WD in the general population, ceruloplasmin levels are routinely measured through hepatitis screening in both adults and children. Herein, we evaluated the diagnostic value of ceruloplasmin for the diagnosis of WD among children with hepatitis. Methods: We retrospectively reviewed data on serum ceruloplasmin levels measured as a serologic marker for patients with hepatitis at Asan Medical Center (Seoul, Korea) between from January 2004 to November 2013. The diagnosis of WD was confirmed by the identification of pathogenic variants in the ATP7B gene. To determine the diagnostic accuracy of ceruloplasmin, receiver operation characteristic (ROC) curves were constructed and the area under curve (AUC) were calculated. Results: Measurements of serum ceruloplasmin were performed in 2,834 children who had hepatitis. Among these, 181 (6.4%) children were diagnosed with WD. The sensitivity, specificity, and accuracy of a ceruloplasmin level of <20 mg/dL in the discrimination of WD were 93.4%, 84.2%, and 84.8%, respectively. In this study, 418 (14.7%) false-positive cases and 12 (0.4%) false-negative cases were noted. Using a ROC curve, a ceruloplasmin level of ${\leq}16.6mg/dL$ showed the highest AUC value (0.956) with a sensitivity of 91.2%, a specificity of 94.9%, and an accuracy of 94.7%. Conclusion: The measurement of serum ceruloplasmin was frequently used for the screening of WD in children, despite a low positive rate. The diagnostic value of ceruloplasmin may be strengthened by adopting a new lower cut-off level.

• Journal of Life Science
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• v.27 no.3
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• pp.339-345
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• 2017

Carotenoids are natural lipid-soluble pigments, which are produced primarily by bacteria, algae, and plants. Many studies have focused on the identification, production, and utilization of natural sources of astaxanthin from algae, yeast, and crustacean byproducts as an alternative to the synthetic pigment, which is mostly used today. The aim of the present study was to identify a mutant of Paracoccus haeundaensis by exposure to UV and ethyl methanesulfonate (EMS). The mutant was then exposed to nutrient stress conditions to isolate an astaxanthin-hyperproducing strain, followed by characterization of the mutant. The survival rate decreased in accordance with an increase in the UV exposure time and an increase in the EMS concentration. A mutant of the original P. haeundaensis strain was identified that showed hyperproduction of astaxanthin following exposure to UV irradiation (20 min) and EMS treatment (0.4 M concentration). The optimal culture conditions for the PUE mutant were $25^{\circ}C$, pH 7-8, and 3% NaCl. The effects of various carbon and nitrogen sources on the growth and astaxanthin production of PUE were examined. The addition of 1% raffinose and 3% potassium nitrate influenced cell growth and astaxanthin production. The selected mutant exhibited an increase of 1.58 folds in astaxanthin content compared to initial wild type strain. A genetically stable mutant strain obtained using mutagen (UV irradiation and EMS treatment) may be a suitable candidate for further industrial scale production of astaxanthin.

• Journal of Life Science
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• v.14 no.5
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• pp.821-828
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• 2004

The increasing apparent photosynthetic rate per leaf area may improve seed yield in soybean. Leaf area, length and width are related to the photosynthetic capability of the plant. In this study, two populations derived from the cross of Keunolkong, Shinpaldalkong and Iksanl0 were evaluated with simple sequence repeat (SSR) markers to identify length, width and length/width ratio of leaf. Leaf length/width ratio were significantly negative correlation with leaf width in K/S and K/I populations. In the K/S population, two minor QTLs for leaf length (LL) were found on LG Dlb+W and 1. Two QTLs on LG J and L were related to LL in K/I population. Two and three minor QTLs were identified in leaf width with total phenotypic variation of 13% and 18.04 in K/S and K/I populations, respectively. The leaf length/width ratio, two QTLs on LG I and L, and three QTLs on LG Cl, E and L were related to K/S and K/I populations, respectively. Thus it is assumed that the leaf traits are very much dependent on the genotype used and different breeding approach should be considered for the selection of favorite leaf traits in soybean breeding programs.

• Journal of Yeungnam Medical Science
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• v.29 no.2
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• pp.83-88
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• 2012

Background: This study was conducted to evaluate the usefulness of the BACTEC MGIT (Mycobacterium Growth Indicator Tube) 960 system for mycobacteria culture and immunochromatographic assay to identify Mycobacterium tuberculosis (MTB) in positive MGIT culture. Methods: Mycobacteria-culture-positive cases were retrospectively analyzed from December 2010 to July 2011. The detection rates and the recovery times of the mycobacteria between the Ogawa media and the MGIT were compared. An immunochromatographic assay (ICA) (SD BIO-LINE) was also performed in the positive MGIT culture for identification, and the results were compared with those of the Ogawa media in the Korea National Tuberculosis Association. Results: Among the 261 patients (M:F, 168:93; mean age, $61.6{\pm}17.16$ yrs), 450 specimens (sputa, 365; bronchial washing, 61; and pleural effusion, 24) were found positive with mycobacteria. Mycobacteria were grown both on the MGIT and Ogawa media in 310 cases (68.9%); only on the MGIT in 115 cases (22.6%); and only on the Ogawa media in 25 cases (5.5%) (p<0.05). The recovery time was $28.2{\pm}8.9$ days in the Ogawa media and $11.1{\pm}5.8$ days in the MGIT (p<0.05). Among the 127 cases from the positive MGIT culture, all 92 cases that were confirmed as MTB cases bythe Korea National Tuberculosis Association were identified as MTB by ICA, with 100% sensitivity. Conclusion: MGIT increases the detection rate and shortens the recovery time of mycobacteria in clinical respiratory specimens, and the TB Ag MPT64 kit using ICA is useful in identifying MTB in a positive MGIT culture.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7959-7965
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• 2015

Background: Identification of predictive markers for the efficacy of platinum-based chemotherapy is necessary to improve the quality of the life of cancer patients. Materials and Methods: We detected proteins recognized by autoantibodies in pretreated sera from patients with lung adenocarcinoma (AC) evaluated as showing progressive disease (PD) or a partial response (PR) after cisplatin-based chemotherapy by proteomic analysis. Then, the levels of the candidate autoantibodies in the pretreated serum were validated by dot-blot analysis for 22 AC patients who received platinum-based chemotherapy, and the expression of identified proteins was immunohistochemically analyzed in 40 AC biopsy specimens. Results: An autoantibody against galectin-3 (Gal-3) was detected in pretreated sera from an AC patient with PD. Serum IgG levels of anti-Gal-3 autoantibody were significantly higher in patients evaluated with PD than in those with PR and stable disease (SD) (p = 0.0084). Furthermore, pretreated biopsy specimens taken from patients evaluated as showing PD following platinumbased chemotherapy showed a tendency to have a higher positive rate of Gal-3 than those with PR and SD (p = 0.0601). Conclusions: These results suggest that serum IgG levels of anti-Gal-3 autoantibody may be useful to predict the efficacy of platinum-based chemotherapy for patients with lung AC.