• Microbiology and Biotechnology Letters
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• 제41권2호
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• pp.221-227
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• 2013

The methane oxidation characteristics at the top and bottom layers in up-flow biofilters were investigated. Two biofilters were packed with perlite and tobermolite (biofilter A: respectively top and bottom; biofilter B: respectively bottom and top) and then compared. The methane oxidation rate was analyzed with the packed bed of the biofilter layers. The bacterial population in the biofilter was characterized using quantitative real-time PCR. For the methane oxidation rate of the biofilter A column, the perlite top part ($845.16{\pm}64.78{\mu}mol{\cdot}VS^{-1}{\cdot}h^{-1}$) gave a relatively higher value than the tobermolite bottom part ($381.85{\pm}42.00{\mu}mol{\cdot}VS^{-1}{\cdot}h^{-1}$). For the methane oxidation rate of the biofilter B column, the tobermolite top part ($601.25{\pm}37.78{\mu}mol{\cdot}VS^{-1}{\cdot}h^{-1}$) provided a relatively higher value than the perlite bottom part ($411.07{\pm}53.02{\mu}mol{\cdot}VS^{-1}{\cdot}h^{-1}$). The pmoA gene copy numbers, responsible for methanotrophs, in the top layer of biofilter A (1.27E+13 pmoA gene copy number/mg-VSS) was higher than in the bottom layer (3.33E+13 pmoA gene copy number/mg-VSS). However, the population of methanotrophs in biofilter B was not significantly different between the top and bottom layers. These results suggest that although the methane oxidation rates of perlite and tobermolite in the top parts of biofilter A and B were high, methanotroph populations were higher in the bottom parts of both biofilters, with a rapid decline in methane concentrations within the biofilters.

• Microbiology and Biotechnology Letters
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• 제34권2호
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• pp.166-173
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• 2006

This research has been performed to clarify the relationship between hydrogeochemistry and bacterial community structure in groundwater contaminated with landfill leachate. We collected and analyzed samples from 5 sites such as leachate (KSG1-12), treated leachate (KSG1-16), two contaminated groundwaters (KSG1-07 and KSG1-08) and non-contaminated groundwater (KSG1-13). pH was 8.83, 8.04, 6.87, 6.87 and 6.53 in order; redox potential (Eh) 108, 202, 47, 200 and 154 mV; electric conductivity (EC) 3710, 894, 1223, 559 and 169.9 $\mu$S/cm; suspended solids (SS) 86.45, 13.74, 4.18, 0.24 and 11.91 mg/L. In KSG01-12, the ion concentrations were higher especially in $Cl^-$ and $HCO_3^-$ than other sites. The concentrations of Fe, Mn and $SO_4^{2-}$ were higher In KSG1-07 than in KSG1-08, and vise versa in $NO_3^{2-}$. In the comparison of DGGE fingerprint patterns, the similarity was highest between KSG1-13 and KSG1-16 (57.2%), probably due to common properties like low or none contaminant concentrations. Otherwise KSG1-08 showed lowest similarities with KSG1-13 (25.8%) and KSG1-12 (27.6%), maybe because of the degree of contamination. The most dominant bacterial species in each site were involved in $\alpha$-Proteobacteria (55.6%) in KSG1-12, $\gamma$-Proteobacteria (50.0%) in KSG1-16, $\beta$-Proteobacteria (66.7%) in KSG1-07, $\gamma$-Proteobacteria (54.5%) in KSG1-08 and $\beta$-Proteobacteria (36.4%) in KSG1-13. These results indicate that the microbial community structure might be changed according to the flow of leachate in grounderwater, implying changes in concentrations of pollutants, available electron accepters and/or other environmental conditions.

• Journal of the Korean Applied Science and Technology
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• 제36권4호
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• pp.1385-1398
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• 2019

This study was a survey study to provide the base data necessary to prepare efficient management plans for the mothers with disabled children by type, comparing degrees of disability acceptance, stress, coping method and wellness between mothers with physical functional disordered children and developmental disordered children. The study subjects were a mother who raises disordered children. Data collection was conducted from October 2018 to April 2019, and differences between the two groups were analyzed as t-test, ANOVA, and Pearson correlation. In results, Studies have shown that there are differences between the two groups as mothers with physical functional disordered children and mothers with developmental disordered children as degrees of disability acceptance, stress, treatment and wellness. Disability acceptance and coping method of mothers with physical functional disordered children (r=0.23, p=.033), disability acceptance and Wellness (r=0.51, p<.001) have shown positive correlations and disability acceptance and stress (r=-0.72, p<.001) have shown negative correlations. Disability acceptance and wellness (r=0.40, p<.001) of the mother with a developmental disordered child have shown a significant positive correlation, and disability acceptance and stress (r=-0.71, p<.001) have shown a significant negative correlations. The higher the degree of disability acceptance, the lower the stress level and the higher the coping method and wellness mothers with physical functional disordered children had. The higher disability acceptance, the lower stress degrees and the higher wellness degrees mothers with developmental disordered children had. In order to improve disability acceptance by mothers with physical functional disordered children, it was necessary to improve both coping methods and wellness with stress reducing strategy, while the mother with developmental disordered children were needed strategies to reduce stress and improve wellness.

• Korean Journal of Materials Research
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• 제5권1호
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• pp.42-54
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• 1995

$Ta_2O_5$ thin film IS a promising material for the high dielectrics of ULSI DRAM. In this study, $Ta_2O_5$ thin film was grown on p-type( 100) Si wafer by thermal metal organic chemical vapo deposition ( MCCVD) method and the effect of operating varialbles including substrate temperature( $T_s$), bubbler temperature( $T_ \sigma$), reactor pressure( P ) was investigated in detail. $Ta_2O_5$ thin film were analyzed by SEM, XRD, XPS, FT-IR, AES, TEM and AFM. In addition, the effect of various anneal methods was examined and compared. Anneal methods were furnace annealing( FA) and rapid thermal annealing( RTA) in $N_{2}$ or $O_{2}$ ambients. Growth rate was evidently classified into two different regimes. : (1) surface reaction rate-limited reglme in the range of $T_s$=300 ~ $400 ^{\circ}C$ and (2: mass transport-limited regime in the range of $T_s$=400 ~ $450^{\circ}C$.It was found that the effective activation energies were 18.46kcal/mol and 1.9kcal/mol, respectively. As the bubbler temperature increases, the growth rate became maximum at $T_ \sigma$=$140^{\circ}C$. With increasing pressure, the growth rate became maximum at P=3torr but the refractive index which is close to the bulk value of 2.1 was obtained in the range of 0.1 ~ 1 torr. Good step coverage of 85. 71% was obtained at $T_s$=$400 ^{\circ}C$ and sticking coefficient was 0.06 by comparison with Monte Carlo simulation result. From the results of AES, FT-IR and E M , the degree of SiO, formation at the interface between Si and TazO, was larger in the order of FA-$O_{2}$ > RTA-$O_{2}$, FA-$N_{2}$ > RTA-$N_{2}$. However, the $N_{2}$ ambient annealing resulted in more severe Weficiency in the $Ta_2O_5$ thin film than the TEX>$O_{2}$ ambient.

• Journal of Life Science
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• 제20권10호
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• pp.1532-1537
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• 2010

This study compared the inhibitory effects of methanol extracts from yellow and black soybeans (black soybean, Seomoktae and Seoritae) on mutagenicity using the Ames test and growth of human cancer cells (AGS human gastric adenocarcinoma, HT-29 human colon cancer, Hep 3B hepatocellular carcinoma cells). In the Ames test system using Salmonella typhimurium TA100, aflatoxin $B_1$ ($AFB_1$)-induced mutagenicity was significantly inhibited by treatments with the methanol extracts from either yellow or black soybeans in a dose dependent manner (p<0.05). The methanol extracts from various black soybeans tended to have a greater inhibitory effect compared to those from yellow soybeans. As for N-methyl-N'-nitro-N-nitrosoguamidine (MNNG)-induced mutagenicity, the methanol extracts (5 mg/assay) from black soybean, Seomoktae and Seoritae showed 51%, 61% and 53% inhibitory rates, respectively, indicating that Seomoktae, a type of black soybean, had a stronger antimutagenic activity against mutagens (both $AFB_1$ and MNNG). Methanol extracts from black soybeans showed an inhibitory rate of greater than 50% on the growth of human cancer cells (AGS, HT-29 and Hep 3B) and the inhibition was more effective in the methanol extract from Seomoktae. Our results suggested that the methanol extracts from black soybeans showed stronger inhibitory effects on mutagenicity and growth of cancer cells than those from yellow soybean. It is concluded that intake of black soybean can be recommended for improving health.

• KSBB Journal
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• 제22권5호
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• pp.288-296
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• 2007

Monascus pilosus (KCCM 60160) in submerged culture was optimized based on culture medium and fermentation conditions. Monacolin-K (Iovastatin), one of the cholesterol lowing-agent which was produced by Monascus pilosus may maintain a healthy lipid level by inhibiting the biosynthesis of cholesterol. Plackett-Burman design and response surface method were employed to study the culture medium for the desirable monacolin-K production. As a result of experimental designs, optimized production medium components and concentrations (g/L) were determined on soluble starch 96, malt extract 44.5, beef extract 30.23, yeast extract 15, $(NH_4)_2SO_4$ 4.03, $Na_2HPO_4{\cdot}12H_2O$ 0.5, L-Histidine 3.0, $KHSO_4$ 1.0, respectively. Monacolin-K production was improved about 3 times in comparison with shake flask fermentation of the basic production medium. The effect of agitation speed (300, 350, 400 and 450 rpm) on the monacolin-K production were also observed in a batch fermenter. Maximum monacolin-K production with the basic production medium was 68 mg/L when agitation speed was 500 rpm. And it was found that all spherical pellets (average diameter of $1.0{\sim}1.5mm$) were dominant during fermentation. Based on the results, the maximum production of 185 mg/L of monacolin-K with the optimized production medium was obtained at pH (controlled) 6.5, agitation rate 400 rpm, aeration rate 1 vvm, and inoculum size 3%.

• Culinary science and hospitality research
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• 제17권4호
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• pp.263-272
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• 2011

For tomatoes containing valuable nutrients and biological active substances, this study examined differences in the ascorbic acid, lycopene, ${\beta}$-carotene, and ${\alpha}$-carotene contents in processed tomato products according to tomato cultivar and the part of fully ripened tomatoes. According to the results, the ascorbic acid content was different among tomato cultivars, and it was far higher in jelly than in pulp among the parts of tomatoes. The ascorbic acid content in processed tomato products was higher in tomato juice than in other types of tomato products, but the difference was mainly from various additives used in addition to tomatoes; therefore, it was somewhat unreasonable to compare the ascorbic acid content among the products. It was found that the lycopene content was not significantly different between pulp and jelly in each cultivar. In most of the cultivars, the ${\beta}$-carotene content was not significantly different according to the parts, but in cultivar yeoyong, the content was 2.7 times higher in jelly than in pulp. The ${\alpha}$-carotene content was highest in both pulp and jelly for all the cultivar, and the lycopene and ${\beta}$-carotene contents were lowest regardless of parts for cultivar Yellow Carol. ${\alpha}$ carotene was not detected in either pulp or jelly. The lycopene, ${\beta}$-carotene, and ${\alpha}$-carotene contents showed significant difference among processed tomato products, and the difference came mainly from the type of processing and additives. Tomatoes have superior characteristics, but they are usually consumed uncooked in Korea. Thus, this study aimed to contribute to the various forms of consumption of tomatoes, that is, the development of various nutritionally excellent cooking methods using processed tomato products.

• The Journal of the Acoustical Society of Korea
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• 제37권4호
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• pp.223-231
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• 2018

Recently, due to various environmental problems, blast tracks in tunnel are replaced with concrete tracks, but they have more adverse effects on noise than blast tracks so that additional noise measures are needed. Among these measures, sound-absorbing blocks start to be used due to its easy and quick installation. However, the performance of sound absorption blocks need to be verified under real environmental and operational conditions. In this paper, interior noise levels in KTX train cruising in Dalseong tunnel are measured before and after the installation of sound-absorbing blocks and the measured data are analyzed and compared. Additionally, noise reduction are estimated by modeling the high speed train, the tunnel and absorption blocks. Measurement devices and methods are used according to ISO 3381 and the equivalent sound pressure levels during the cruising time inside the tunnel are computed. In addition to overall SPLs(Sound Pressure Levels), 1/3-octave-band levels are also analyzed to account for the frequency characteristics of sound absorption and equipment noise in a cabin. In addition, to consider the effects of train cruising speeds and environmental conditions on the measurements, the measured data are corrected by using those measured during the train-passing through the tunnels located before and behind the Dalseong tunnel. Analysis of measured results showed that the maximum noise reduction of 6.8 dB (A) can be achieved for the local region where the sound-absorbing blocks are installed. Finally, through the comparison of predicted 1/3-octave band SPLs for the KTX interior noise with the measurements, the understanding of noise reduction mechanism due to sound-absorbing blocks is enhanced.

• Journal of Yeungnam Medical Science
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• 제24권2호
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• pp.119-128
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• 2007

Purpose : The purpose of this study was a phantom study to measure the diffusion properties of water molecules by steady-state free precession diffusion-weighted imaging (SSFP- DWI) with a low b-value and to determine if this sequence might be useful for application to the evaluation of bone marrow pathology. Materials and methods : 1. The phantom study: A phantom study using two diffusion weighted sequences for the evaluation of the diffusion coefficient was performed. Three water-containing cylinders at different temperatures were designed: phantom A was $3^{\circ}C$, B was $23^{\circ}C$ and C was $63^{\circ}C$. Both SSFP and echo planar imaging (EPI) sequences (b-value: $1000s/mm^2$) were performed for comparison of the diffusion properties. The Signal to noise ratios (SNR) and apparent diffusion coefficient (ADC) values of the three phantoms using each diffusion-weighted sequence were assessed. 2. The Clinical study: SSFP-DWI was performed in 28 patients [sacral insufficiency fractures (10), osteoporotic lumbar compression fractures (10), malignant compression fractures (8)]. To measure the ADC maps, a diffusion-weighted single shot stimulated echo-acquisition mode sequence ($650s/mm^2$) was obtained using the same 1.5-T MR imager Results : For the phantom study, the signal intensity on the SSFP as well as the classic EPI-based DWI was decreased as the temperature increased in phantom A to C. The ADC values of the phantoms on EPI-DWI were $0.13{\times}10^{-3}mm^2/s$ in phantom A, $0.22{\times}10^{-3}mm^2/s$ in B and $0.37{\times}10^{-3}mm^2/s$. in C. The SSFP can be regarded as a DWI sequence in view of the series of signal decreases. Conclusion : Bone marrow pathologies with different diffusion coefficients were evaluated by SSFP-DWI. All benign fractures were hypointense compared to the adjacent normal bone marrow where as the malignant fractures were hyperintense compared to the adjacent normal bone marrow.

• Clinical and Experimental Pediatrics
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• 제46권10호
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• pp.1013-1018
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• 2003

Purpose : Bronchial hyperresponsiveness(BHR) in asthma is thought to be a consequence of underlying airway inflammation. But the mechanism responsible for persistent BHR in adolescents with long-term asthma remission is poorly understood. The aim of this study was to examine whether BHR in adolescents with asthma remission is associated with peripheral blood eosinophilia and/or increased serum levels of eosinophil cationic protein(ECP). Methods : We studied 35 adolescents with long-term asthma remission(neither symptoms nor medication during the previous two years) who have persistent BHR(remission group) and 35 adolescents with symptomatic asthma(symptomatic group) who were matched for methacholine provocative concentration producing a 20% fall in $FEV_1(PC_{20})$ with subjects in the remission group. The peripheral blood eosinophil counts and serum ECP concentrations were compared between these two groups. Correlations between $PC_{20}$ and peripheral blood eosinophil counts or serum ECP concentrations were assessed in these two groups. Results : Peripheral blood eosinophil counts and serum ECP concentrations were significantly lower in the remission group than in the symptomatic group($273{\pm}108$ vs. $365{\pm}178/{\mu}L$; $16.3{\pm}9.4$ vs. $26.5{\pm}15.1{\mu}g/L$, both, P<0.05). $PC_{20}$ was correlated with peripheral blood eosinophil counts and serum ECP concentrations in the symptomatic group(r=-0.385, P=0.022; r=-0.439, P=0.008), but not in the remission group(r=-0.292, P=0.089; r=-0.243, P=0.159). Conclusion : BHR in adolescents with long-term asthma remission is not associated with peripheral blood eosinophilia or an increase in serum ECP concentration, which suggests that BHR in this clinical setting may not be attributed to airway eosinophilic inflammation. Further studies including direct assessment of airway inflammation are needed to confirm this conclusion.