• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.123-129
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• 2005

Isolation and identification of pathogens from slaughter and meat processing plant were investigated. Antimicrobial activity of Amaranthus lividus against isolated pathogens such as Aeromonas sobria, Escherichia coli, Escherichia coli O157, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus was investigated. Among the chloroform, ethyl acetate and buthanol fraction of amaranthus lividus showed inhibitory effect against Aeromonas sobria CLFM1 and Escherichia coli CLFM2. Antimicrobial substance in chloroform fraction was isolated by silica gel adsorption column chromatography, sephadex LH-20 column chromatography and silica gel partition column chromatography. The antimicrobial compound of amaranthus lividus was identified as diethyl phtalate by HPLC, GC-MS, H-NMR and C-NMR.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.62-69
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• 2020

This study examined Internet discourse on inter-regional co-prosperity. In particular, the study is interested in the co-prosperity between the Daegu-Gyeongbuk regions. The Internet discourse was searched through a set of four keywords: co-prosperity, economy, business attraction, and cultural tourism. The study also conducted sentiment analysis of YouTube comments to determine how the Internet responds to co-prosperity topics. The findings of the analysis are as follows. First, Internet discourse related to co-prosperity has evolved from abstract concepts to concrete cooperative measures and policy contents. Second, the discussion of co-prosperity has moved from outside help or support to self-sustaining innate motivation. Finally, YouTube sentiment analysis showed that if co-prosperity efforts between regions are promoted through concrete policy contents, it becomes easier to gain positive responses from citizens and lead a positive policy drive. In this regard, a study on Internet discourse is a useful means to detect citizens' response to inter-regional co-prosperity.

• Bulletin of the Korean Chemical Society
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• v.28 no.4
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• pp.581-588
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• 2007

To enhance the photodecomposition of concentrated ammonia into N2, Pt/V-TiO2 photocatalysts were prepared using solvothermal and impregnation methods. Nanometer-sized particles of 0.1, 0.5 and 1.0 mol% V-TiO2 were prepared solvothermally, and then impregnated with 1.0 wt% Pt. The X-ray diffraction (XRD) peaks assigned to V2O5 at 30.20 (010) and Pt metal at 39.80 (111) and 46.20 (200) were seen in the 1.0 wt% Pt/ 10.0 mol% V-TiO2. The particle size increased in the order: pure TiO2, V-TiO2 and Pt/V-TiO2 after thermal treatment at 500 °C, while their surface areas were in the reverse order. On X-ray photoelectron spectroscopy (XPS), the bands assigned to the Ti2p3/2 and Ti2p1/2 of Ti4+-O were seen in all the photocatalysts, and the binding energies increased in the order: TiO2 < Pt/V-TiO2 < V-TiO2. The XPS bands assigned to the V2p3/2 (517.85, 519.35, and 520.55 eV) and V2p1/2 (524.90 eV) in the V3+, V4+ and V5+ oxides appeared over V-TiO2, respectively, while the band shifted to a lower binding energy with Pt impregnation. The Pt components of Pt/ V-TiO2 were identified at 71.60, 73.80, 75.00 and 76.90 eV, which were assigned to metallic Pt 4f7/2, PtO 4f7/2, PtO2 4f7/2, and PtO 4f5/2, respectively. The UV-visible absorption band shifted closer towards the visible region of the spectrum in V-TiO2 than in pure TiO2 and; surprisingly, the Pt/V-TiO2 absorbed at all wavelengths from 200 to 800 nm. The addition of vanadium generated a new acid site in the framework of TiO2, and the medium acidic site increased with Pt impregnation. The NH3 decomposition increased with the amount of vanadium compared to pure TiO2, and was enhanced with Pt impregnation. NH3 decomposition of 100% was attained over 1.0 wt% Pt/1.0 mol% V-TiO2 after 80 min under illumination with 365 nm light, although about 10% of the ammonia was converted into undesirable NO2 and NO. Various intermediates, such as NO2, -NH2, -NH and NO, were also identified in the Fourier transform infrared (FT-IR) spectra. From the gas chromatography (GC), FT-IR and GC/mass spectroscopy (GC/MS) analyses, partially oxidized NO and NO2 were found to predominate over V-TiO2 and pure TiO2, respectively, while both molecules were reduced over Pt/V-TiO2.

• Journal of Korea Water Resources Association
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• v.50 no.9
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• pp.587-595
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• 2017

Hydraulic characteristics affecting sediment transport capacity due to the weir operations were investigated and developed sediment rating curves for four gaging stations (Nakdong, Gumi, Waegwan, and Jindong) in Nakdong River. Analysis found that the sediment transportaion capability had been decreased and it could be proved from the field measurement records in 2013. Applicabilities of nine sediment transport prediction techniques, which are imbeded in GUIDE program, were examined and adopted for the four gaging stations. Analysis of sediment balance for Nakdong River, including 9 major tributaries, had been carried out with pseudo 2-D numerical model and found that: 1) sedimentation phenomena will be prevailed along the Nakdong River. 2) Engelund-Hansen technique shows the least error in estimation of sediment balance. 3) Engelund-Hansen technique most appropriately describes the sediment characteristics for four gaging stations. 4) Estimated error from the sediment balance for Nakdong River was smaller than the error caused by the estimation of sediment incomming from 9 tributries. Therefore, it is necessary to improve the accuracy of predicting the sediment incomming from the tributaties for better sediment balance analysis.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.7
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• pp.721-730
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• 2006

The effects of compost amendment on the removal of petroleum hydrocarbons and the activities of microorganisms in soil ecosystem have been studied in bioremediation of diesel contaminated soil. The relation between biological activities and removal of petroleun hydrocarbon was determined by ATP(Adenisine Triphosphate), n-alkanes and TPH concentration analysis. After 80 days of bioremediation, the removal of TPH in soil amended with compost increased more than 10% compared with control soil which was tilled in the same condition without compost addition. The biodegradations of n-alkanes having 12 to 20 moles of carbon were distinctive. As the soil was contaminated with more diesel, the ATP has decreased rapidly. When the TPH amounted to 80,000 mg diesel/kg, the ATP decreased to 4 ng/g from initial concentration of 65 ng/g. While the ATP in the compost amended soil increased to 112 ng/g after tilling for 6 days, the ATP in the control increased to merely 36 ng/g after tilling for 14 days. Also while the control soil showed a lag time in ATP increase, the compost amended soil did not show that but showed a rapid ATP increase within a short time. The patterns of changes in ATP concentration were similar to those in daily removals of TPH with time difference of about 7 days.

• Korean Journal of Plant Resources
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• v.30 no.1
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• pp.110-123
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• 2017

The authors reviewed the history of creation and management, purposes, extents, methods of creation, planting species and mediums, structure of vegetation layers and legal management, etc. of coastal forests of Korea. Since the Goryeo dynasty, the inhabitants in the coastal regions has long been aware the safety from natural disasters and the local governments manages for the defence and natural disasters, and collaboration among GO and NGOs, as well as enterprises are participating to the conservation of coastal forests in Korea. The purposes of creation and management of coastal forests in historical aspects are prevention of disasters, safety by the Fengsui, military uses, and timber productions, but partly as the places for religious beliefs, safety from diseases and fires, increasing of forest products and fishes, as well as tourists, improving of amenity and landscapes and recreation, inherits of traditional culture, habitats for wildlife, and ecological corridors, etc. The inhabitant in the coastal region who experienced frequent natural disasters has strong supports for the conservation of coastal forest and as a natural resources to inherits to the coming generations as the coastal forests has high values of academic researches on human society, culture, ecology and recreational uses, etc. The extensive overall researches on the creation and managements of coastal forests, as well as cultural tradition in the coastal forests of Korean peninsula are critically essential.

• Food Science and Preservation
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• v.21 no.2
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• pp.181-186
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• 2014

This study was conducted to that investigate the quality characteristics of wet-ground whole-grain buckwheat powder for the buckwheat husk. The particle size of buckwheat rice was 74.84 ${\mu}m$, which was approximately four to five times larger than wet-ground whole buckwheat by wet grinding. The particle size showed that there was no significant difference after 90 min on wet grinding. The total phenolics and total flavonoids contents of the whole buckwheat powder were higher than those of buckwheat rice, and they gradually increased wet grinding progressed. The rutin contents of the buckwheat increased after wet grinding and was 152.90 ppm at 90 min. There was no significant difference in the quercetin contents after wet grinding at different times. The mineral contents (Ca, K and Mg) of the whole buckwheat powder were greater than those of the buckwheat rice. Further, Zn and Mn were detected in the whole buckwheat powder. The total amino acid content of the whole buckwheat powder increased to 22.27 mg%, and the important glutamic acid increased from 14.58 to 30.45 mg%. These study results were based on 90 min wet-grinding time for whole-buckwheat-powder manufacture. Whole buckwheat powder manufactured through wet grinding can be used as an active ingredient of buckwheat husk.

• The Korean Journal of Financial Management
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• v.22 no.1
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• pp.1-36
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• 2005

In this study, we analyzed determinant factors of leverage ratio and debt maturity for Korean firms in the simultaneous equation system using 2SLS (two stage least square) method under assumption that two variables are jointly determined in the capital structure decision. As a result of the analysis, we found that leverage ratio and debt maturity are positively related. Also, as for determinant factors of debt maturity, agency cost hypothesis, asset maturity matching hypothesis, signalling and liquidity risk hypothesis are all generally supported, and further leverage ratio are significantly positively related with firm size, but negatively related with default risk. However, when we divided samples into groups according to bank debt level and Chaebul affiliation, with contrast to existing study which worked on similar issues with OLS, we found no evidence supporting the argument that the information asymmetry problem is less severe in firms with more bank debt, whereas information asymmetry and financial constraint problems are more severe in non-Chaebul affiliated firms.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1092-1098
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• 2011

The present study was conducted to investigate the effect of ${\beta}$-carotene on the antioxidant system of rats with diabetes. Forty Sprague Dawley rats were fed the AIN-76 control diet or the same diet supplemented with ${\beta}$-carotene (7.2 mg/kg diet) for 3 weeks, then diabetes was induced in half the rats by administering streptozotocin (45 mg/kg BW) into the femoral muscle. Diabetic and normal rats were fed the experimental diets for 2 more weeks. To investigate the effect of dietary ${\beta}$-carotene on diabetes, the activities of antioxidative enzymes and glutathione concentration were determined in normal and streptozotocin-induced diabetic rats. The plasma glucose levels in diabetic rats were not influenced by the dietary supplementation of ${\beta}$-carotene. Hepatic activities of catalase and superoxide dismutase in diabetic rats were significantly lower than those of control rats but ${\beta}$-carotene tended to induce these activities. Glutathione-S-transferase activity was not significantly different between experimental groups. Glucose-6-phosphatase activity was induced in diabetic rats, but dietary supplementation of ${\beta}$-carotene reduced this activity. The hepatic concentration of reduced glutathione in diabetic rats was lower than that of control rats, but dietary supplementation with ${\beta}$-carotene restored the content to some extent. These data suggest that diabetic rats are exposed to increased oxidative stress and that dietary supplementation with ${\beta}$-carotene may reduce its detrimental effects.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.3
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• pp.364-370
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• 2007

This study was carried out to investigate the effect of lipid type on the physicochemical properties and sensory score of pork patties. The samples consisted of pork patties containing 20% pork fat (PP), 20% olive oil (OP), and 20% soybean oil (SP). The surface color, water holding capacity, increased rate in thickness, decreased rate in diameter, rheological properties, pH, VBN content and TBARS value were determined for the pork patties as the physicochemical properties: the sensory scores were also evaluated. The $L^*$ value for PP was the highest, and the lowest for OP among the samples (p<0.05). For the $a^*$ value OP was the highest among the samples, and the $b^*$ value of OP was lower than that of the PP (p<0.05). The water holding capacity and increased rate of thickness were higher for PP than for OP and SP (p<0.05). The cooking loss and decreased rate of diameter of PP were lower than those of OP and SP (p<0.05). The hardness and springiness of OP and SP were higher than those of PP, and SP had the highest chewiness among the samples (p<0.05). However, cohesiveness and gumminess were not different among the samples. The pH of SP was the highest among the samples, and the TBARS value of OP was lowest (p<0.05). The VBN contents were not different among the samples. The amounts of raw color for OP and SP were higher than that of PP (p<0.05). The raw aroma was not different among the samples. Also, roasted aroma and taste were not different among the samples, but the tenderness, juiciness, and palatability of SP were the highest among the samples (p<0.05).