• Microbiology and Biotechnology Letters
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• v.34 no.4
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• pp.342-351
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• 2006

The aim of this study was to survey susceptibilities of Escherichia coli and Klebsiella pneumoniae isolates against cefotaxime and to determine the prevalences of CTX-M type extended-spectrum $\beta$-lactamases (ESBLs) producing E. coli and K. pneumoniae in Korea. During the period of February to July, 2005, 153 E. coli and 52 K. neumoniae isolates were collected from 2 hospitals in Busan. Antimicrobial susceptibilities to cefotaxime were tested by the disk diffusion method. ESBL production of E. coli and K. pneumoniae was determined by the double disk synergy test. MICs of $\beta$-lactam antibiotics were determined by the agar dilution method. Blac$_{CTX-M}$ genes of the organism were detected by PCR. Among 153 isolates of E. coli and 52 isolates of K. neumoniae, 27 (17.6%) and 25 (48.0%) were intermediate or resistant to cefotaxime, respectively. Twenty-three (15.0%) isolates out of 153 E. coli and 13 (25.0%) out of 52 K. neumoniae isolates showed positive results for ESBL by the double disk synergy test. Twenty isolates out of 23 ESBL producing E. coli and 12 out of 13 ESBL producing K. neumoniae isolates harbored biacTx-M gene,11 of ESBL producing E. coli and 12 of ESBL producing K. neuinoniae isolates harbored bla$_{CTX-M}$ gene, 11 of the ESBL producing E. coli and 2 of ESBL producing K. neumoniae isolates harbored bla$_{TEM}$ gene, and 1 of the ESBL producing E. coli and 12 of ESBL producing K. neumoniae isolates harbored bla$_{SHV}$ gene. E. coli and K. neumoniae isolates producing CTX-M-type ESBLs were not uncommon in Korea. It is thought that continuous survey are necessary for inspecting the spread and novel variants of CTX-M-type ESBL genes. Further me]'e investigation and research on ESBL producing strains are needed in order to prevent the spread of resistant bacteria.

• Journal of Korean Society of Environmental Engineers
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• v.33 no.12
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• pp.913-921
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• 2011

This study examined the overall feasibility of low carbon green village formed in rural area. The check method is analyzing its environmental and economic feasibility and energy self-reliance. The biomass of the villages was set as 28 ton/day of livestock feces and 2 ton/day of cut fruit tree branches which make up the total of 30 ton/day. The facility consisted of a bio gasfication facility using wet (livestock feces) biomass and combined heat power generator, composting facility and wood boiler using dry (cut fruit tree branches) biomass. When operating the system, 540,540 kWh/yr of electricity and 1,762 Gcal/yr of heat energy was produced. The region's electricity energy and heat energy self-reliance rate will be 100%. The economic feasibility was found as a loss of 140 million won where the facility installation cost is 5.04 billion won, operation cost is 485.09 million won and profit is 337.12 million won. There will be a loss of about 2.2 billion won in 15 years but in the environmental analysis, it was found that crude replacement effect is about 178 million won, greenhouse gas reduction effect is about 92 million won making up the total environmental benefit of 270 million won. This means, there will be a yearly profit of about 130 million won. In terms of its environmental and economic feasibility and energy self-reliance, this project seemed to be a feasible project in overall even if it manages to get help from the government or local government.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.7
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• pp.699-705
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• 2010

In this study, three different biological activated carbons (BACs) were prepared from activated carbons made of each coal (F400, Calgon), coconut (Samchully) and wood(Pica, Picabiol) which were run for two and half years in the pilot plant. The attached bio-film microorganisms in and on the BACs were isolated and identified. The results showed that nine different bacteria species (Chryseomonas luteola, Stenotrophomonas maltophilia, Pseudomonas vesicularis, Aeromonas hydrophila, Spingomonas paucimobilis, Agrobacterium radiobacter, Pseudomonas fluorescens, Spirillum spp., and Pasteurella haemolytica) were isolated and identified, the dominant species was Pseudomonas sp. that had occupied 56.5%. More specifically, it was observed that the populations of the microorganisms deceased in the order: Pasteurella haemolytica (18.9%) > Chryseomonas luteola (4.0%) > Agrobacterium radiobacter (3.5%) > Aeromonas hydrophila (2.0%) in and on the BACs. After isolating of 9 species of biofilm microorganisms, the growth curve for the biomass was investigated. During 24~96 hours, the biomass has the highest concentration, and activity of the biomass was the best to uptake geosmin as carbon resources. The operation temperatures for investigating the biodegradation of geosmin were set at $4^{\circ}C$ and $25^{\circ}C$. Pseudomonas vesicularis, Pseudomonas fluorescens, Agrobacterium radiobacter and Stenotrophomonas maltophilia played a maior role in removing the target compound as geosmin. However, geosmin was not biodegraded well by Chryseomonas luteola, Spingomonas paucimobilis, and Spirillum spp.. It is also interesting to evaluate kinetics of biodegradability of geosmin. The first-order rate constants for biodegradability of geosmin at $4^{\circ}C$ and $25^{\circ}C$ were $0.00006{\sim}0.0002\;hr^{-1}$ and $0.0043{\sim}0.0046\;hr^{-1}$ respectively. Higher water temperature produced better geosmin removal rates. When concentrations of geosmin increased from 10 to 10,000 ng/L, the rate constants for biodegradability of geosmin increased from 0.0003 to $0.0882\;hr^{-1}$. As described earlier, higher geosmin concentration in the reactor produced higher rate constant.

• Korean Chemical Engineering Research
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• v.58 no.3
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• pp.325-345
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• 2020

Determination of Best available technology (BAT) was suggested to reduce volatile organic compounds (VOCs) in a petrochemical industrial complex, by conducting human health risk, environmental, and economic assessment based on multimedia fugacity model. Fate and distribution of benzene, toluene, ethylbenzene, and xylene (BTEX) was predicted by the multimedia fugacity model, which represent VOCs emitted from the industrial complex in U-city. Media-integrated human health risk assessment and sensitivity analysis were conducted to predict the human health risk of BTEX and identify the critical variable which has adverse effects on human health. Besides, the environmental and economic assessment was conducted to determine the BAT for VOCs reduction. It is concluded that BTEX highly remained in soil media (60%, 61%, 64% and 63%), and xylene has remained as the highest proportion of BTEX in each environment media. From the candidates of BAT, the absorption was excluded due to its high human health risk. Moreover, it is identified that the half-life and exposure coefficient of each exposure route are highly correlated with human health risk by sensitivity analysis. In last, considering environmental and economic assessment, the regenerative thermal oxidation, the regenerative catalytic oxidation, the bio-filtration, the UV oxidation, and the activated carbon adsorption were determined as BAT for reducing VOCs in the petrochemical industrial complex. The suggested BAT determination methodology based on the media-integrated approach can contribute to the application of BAT into the workplace to efficiently manage the discharge facilities and operate an integrated environmental management system.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.1-14
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• 2018

We surveyed the distribution of exotic weeds in Korean paddy fields, uplands, orchards and pastures from 12,568 sites during 3 years, 2013, 2014 and 2015. As a result, 166 species in 28 families were identified and 7, 130, 126, and 80 species were surveyed from paddy fields, uplands, orchards, and pastures, respectively. Among the 166 species, 128 species were annual weed and 38 species were perennial weed. Especially, winter annual exotic weeds were 63 species (37.8%). 46, 16, and 104 exotic weeds were classified to their introduction period of $1^{st}$ (1876-1921), $2^{nd}$ (1922-1963), and $3^{rd}$ (1964-now) period, respectively. The exotic weeds introduced in $2^{nd}$ and $3^{rd}$ period, included 12 Invasive Alien Species. The weeds from $1^{st}$ period, however, could be grouped into native weeds as the 'naturalized weed' and managed the same as the native weeds. Especially, some exotic weeds such as common groundsel were widely distributed in Korean crop lands, and they will become more problematic in near future. Therefore, systemic research from the biology to management should be conducted and the results from the studies should be applied practically.

• Progress in Medical Physics
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• v.19 no.1
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• pp.80-88
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• 2008

Recent radiotherapy dose planning system (RTPS) generally adapted the kernel beam using the convolution method for computation of tissue dose. To get a depth and profile dose in a given depth concerened a given photon beam, the energy spectrum was reconstructed from the attenuation dose of transmission of filter through iterative numerical analysis. The experiments were performed with 15 MV X rays (Oncor, Siemens) and ionization chamber (0.125 cc, PTW) for measurements of filter transmitted dose. The energy spectrum of 15MV X-rays was determined from attenuated dose of lead filter transmission from 0.51 cm to 8.04 cm with energy interval 0.25 MeV. In the results, the peak flux revealed at 3.75 MeV and mean energy of 15 MV X rays was 4.639 MeV in this experiments. The results of transmitted dose of lead filter showed within 0.6% in average but maximum 2.5% discrepancy in a 5 cm thickness of lead filter. Since the tissue dose is highly depend on the its energy, the lateral dose are delivered from the lateral spread of energy fluence through flattening filter shape as tangent 0.075 and 0.125 which showed 4.211 MeV and 3.906 MeV. In this experiments, analyzed the energy spectrum has applied to obtain the percent depth dose of RTPS (XiO, Version 4.3.1, CMS). The generated percent depth dose from $6{\times}6cm^2$ of field to $30{\times}30cm^2$ showed very close to that of experimental measurement within 1 % discrepancy in average. The computed dose profile were within 1% discrepancy to measurement in field size $10{\times}10cm$, however, the large field sizes were obtained within 2% uncertainty. The resulting algorithm produced x-ray spectrum that match both quality and quantity with small discrepancy in this experiments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1238-1243
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• 2008

The root of Adenophora triphylla is widely used as traditional herbal medicine in Korea. We studied its effects on sodium nitroprusside (SNP) cytotoxicity and antioxidant genes expression in HepG2 cells. To study whether Adenophora triphylla ethylacetate extract (ATea) inhibited NO-induced cell death, HepG2 cells were preincubated for 24 hr with 50 and 100 $\mu$g/mL ATea followed by 24-hr exposure to 0.5 mM SNP (exogenous NO donor). No-induced cytotoxicity was inhibited by pretreatment of ATea, as assessed by mitochondrial dehydrogenase activity (MTT assay). We further investigated the effects of ATea on mRNA levels of various enzymes of the antioxidant system such as Cu, Zn superoxide dismutase (SOD 1), Mn SOD (SOD 2), glutathione peroxidase (GPx), catalase and several enzymes of the glutathione metabolism [glutathione reductase (GR), $\gamma$-glutamyl-cystein synthetase (GCS), glutathione-S-transferase (GST), $\gamma$-glutamyltranspeptidase ($\gamma$-GT), glucose-6-phosphate dehydrogenase (G6PD)] by RT-PCR. CAT, GCS, GR and G6PD mRNA levels were increased after treatment with ATea. The SOD 1, SOD 2, GPx, GST and $\gamma$-GT mRNA levels were not affected in ATea-treated HepG2 cells. We concluded that ATea have an indirect antioxidant effects, perhaps via induction of CAT, GCS, GR and G6PD.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.

• KSBB Journal
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• v.23 no.1
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• pp.90-95
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• 2008

In this study, a combined process of sequential anaerobic-aerobic digestion (SAAD), fluidized-bed bioreactor (FBBR), and ultrafiltration (UF) for the treatment of small scale food waste leachate was developed and evaluated. The SAAD process was tested for performance and stability by subjecting leachate from food waste to a two-phase anaerobic digestion. The main process used FBBR composed of aerators for oxygen supply and fluidization, three 5 ton reaction chambers containing an aerobic mesophilic microorganism immobilized in PE (polyethylene), and a sedimentation chamber. The HRTs (hydraulic retention time) of the combined SAAD-FBBR-UF process were 30, 7, and 1 day, and the operation temperature was set to the optimal one for microbial growth. The pilot process maintained its performance even when the CODcr of input leachate fluctuated largely. During the operation, average CODcr, TKN, TP, and salt of the effluent were 1,207mg/L, 100mg/L, 50 mg/L, and 0.01 %, which corresponded to the removal efficiencies of 99.4%, 98.6%, 89.6%, and 98.5%, respectively. These results show that the developed process is able to manage high concentration leachate from food waste and remove CODcr, TKN, TP, and salt effectively.

• Journal of Animal Science and Technology
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• v.47 no.4
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• pp.565-572
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• 2005

An experiment was conducted to determine the effect of supplementation of insoluble dietary fiber (Vitacel®) on growth performance and nutrient digestibility in weanling pigs. A total of 96 pigs that averaged 6.49$\pm$0.52kg BW and 23$\pm$2.1d age were allocated in a randomized block design with two pigs per pen and 12 pens per treatment. Pigs and feeders were weighed 10-days interval for the 40-d trials to determine ADG, ADFI and feed:gain ratio(F:G). Pigs were fed one of four diets:1) Control diet (C) 2) C+0.3% insoluble dietary fiber(IDF) 3) C+0.6% IDF and 4) c+0.9% IDF. For the determination of fecal nutrients digestibility, pigs were fed diets(diet 2) with 1% Celite-545(Fluka) as a marker and feces were collected on $9^{th}$ day and $18^{th}$ day after feeding diet 2. During the whole experimental period, pigs fed diet with 0.3% IDF have significantly higher ADG than other dietary treatment groups(P<0.05). ADG of pigs fed diet with 0.6% IDF was higher than that of pigs fed control diet(P<0.05). However, there was no significant difference in ADG between control group and 0.9% IDF group(P>0.05). ADFI of pigs fed diet with 0.3% IDF was significantly higher than any other dietary treatment groups(P<0.05). There was no significant difference in ADFI among control group, 0.6% and 0.9% IDF supplementation groups (P>0.05). Digestibilities of organic matter, crude protein, crude fiber and energy were significantly higher in 0.3% IDF supplementation group than any other dietary groups. However, there was no difference in over all nutrient digestibilities between 0.6% and 0.9% IDF group. Feeding diets more than 0.6% IDF did not affect the rest of the nutrients digestibilities except for ADF digestibility compared to control diet. Dietary supplementation level of IDF showed a significant quadratic effect on performance improvement of piglets. This response of growth performance to IDF supplementation is, as expected, in agreement with that of nutrient digestibility. Our results showed that IDF supplementation to diet for weaned piglets might be beneficial in terms of growth and nutrient digestibility. However, there should be more study on the relationship between level of IDF supplementation and piglet response as well as the exact mode of action of IDF in weaned piglets.