• Microbiology and Biotechnology Letters
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• v.33 no.2
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• pp.96-105
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• 2005

For screening of autoregulator receptor gene from Streptomyces longwoodensis, PCR was performed with primers of receptor gene designed on the basis of amino acid sequences of autoregulator receptor proteins with known function. PCR products were subcloned into the BamHIsite of pUC19 and transformed into the E. coli $DH5{\alpha}$. The isolated plasmid from transformant contained the fragment of 100 bp, which was detected on $2\%$ gel after BamHI treatment. The insert, 100 bp PCR product, was confirmed as the expected internal segment of gene encoding autoregulator receptor protein by sequencing. Southern and colony hybridizations with the 100 bp fragment as a probe allowed to select a genomic clone of S. longwoodensis, pSLT harboring a 4.4 kb SphI fragment. Nucleotide sequencing analyses revealed a 651 bp open reading frame(ORF) were isolated protein showing moderate homology ($35{\sim}46\%$) with the ${\Gamma}$-butyrolactone autoregulator receptors from Streptomyces sp., and this ORF was named sltR The sltR/pET-17b plasmid was constructed to overexpress the recombinant SltR protein (rSltR) in E. coli BL21 (DE3)/pLysS, and the rSltR protein was purified to homogeneity by DEAE-Sephacel column chromatography, and DEAE-5PW chromatography (HPLC). The molecular mass of the purified rSltR protein was 55 kDa by HPLC gel-filtration chromatography and 28 kDa by SDS-PAGE, indicating that the rSltR protein is present as a dimer. A binding assay with tritium-labeled autoregulators revealed that the rSltR has clear binding activity with a A-factor type autoregulator as the most effective ligand.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.6
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• pp.414-420
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• 2012

In an effort to commercialization of energy saving aeration apparatus, panel-type aeration membranes were prepared from polyurethane sheet of J company in Korea having tensile strength higher than $400kg_f/cm^2$ with thickness of 0.5mm. Micropores of 100 m size were made by poring technique utilizing needles. From lab-tests in 450 L water tank at temperature of $20^{\circ}C$, the performance of aeration panels at 40 L/min aeration rate showed 5 mg/L DO in less than 3 minutes approaching saturation point of 8 mg/L within 8 minutes. The results show very high efficiency with $K_{La(15)}$ ($16.34hr^{-1}$), Standard oxygen transfer efficiency (SOTE 54.7%) and Standard aeration efficienct (SAE 7.88 kg/kwh). Other pilot scale test in a $2m^3$ water tank with water temperature ($19^{\circ}C$) and aeration rate (30 L/min) showed DO exceeding 5 mg/L within 8 minutes along with $K_{La(15)}$ ($5.8hr^{-1}$), SOTE (42.1%) and SAE (6.41 kg/kwh). These efficiencies represent 2~2.5 times higher than conventional aeration devices. Especially, the achievement of higher Oxygen Transfer Rate indicate higher commercial viability. Conventional aeration devices when applied to clean water and wastewater frequently cause problems due to differences in actual Oxygen Transfer Rate. Our actual tests with $40^{\circ}C$ animal farm wastewater resulted very high efficiencies with Oxygen transfer efficiency ($OTE_f$ 22.1%) and $OTE_{pw40}$ (39.6%).

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.2
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• pp.135-142
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• 2012

Exchangeable cations are often overestimated especially in salt-affected soils due to the presence of high levels of soluble ions in soil solution. Thus, quantitative analysis of the soil exchangeable cation based on ammonium acetate extraction method {(Exch. Cation)$_{total}$} requires additional process to remove the free ions (pre-washing) in soil with distilled water or alcohol {(Exch. Cation)$_{pw}$} or subtraction of the soluble ion contents from the total exchangeable cations {(Exch. Cation)$_{ref}$}. In this research, we compared the three different methods for the determination of exchangeable cations in soils affected by different types of salt accumulation such as the soils from upland, plastic film house, and reclaimed tidal land. In upland soils, non-saline and non-sodic soils, the regular ammonium acetate extraction method did not have any problem to determine the content of exchangeable cations without any additional process such as the pre-washing method or the subtraction method. However, the contents of exchangeable cations in the salt-affected soils might be determined better with the pre-washing method for the plastic film house soils and with the subtraction method for the reclaimed tidal land soils containing high Na.

• Journal of Life Science
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• v.27 no.1
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• pp.50-56
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• 2017

An antibacterial peptide was purified from an acidified gill extract of the pufferfish Takifugu pardalis. The acidified gill extract was put through a Sep-Pak C18 solid phase extraction cartridge using a stepwise gradient and divided into a flow-through (F.T.) and 60% methanol fraction (RM 60). Among the eluents, RM 60 had potent antibacterial activity against Bacillus subtilis KCTC 1021. RM 60 was partially purified on a cationic-exchange column (SP-5PW) by a linear gradient, and the antibacterial peptide was then further purified, using a series of cationic-exchange and $C_{18}$ reversed-phase HPLC columns. For characterization of the purified peptide, its molecular weight and amino acid sequence were analyzed by MALDI-TOF MS and Edman degradation. The molecular weight of the peptide was about 1171.6 Da. The amino acid sequence of the peptide was partially determined as: STKEKAPRKQ. A comparison of the N-terminal amino acid sequence of the purified peptide with that of other known polypeptides revealed high homology with the N-terminus of the histone H3 protein, which belongs to the histone H3 family. Thus, this peptide was designated as a puffer fish gill (PFG)-related antimicrobial peptide. This is the report to describe an antimicrobial function for the N-terminus of histone H3 of an animal species. The findings suggest that this peptide plays a significant role in the innate defense system of the pufferfish.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.469-478
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• 2019

Car-sharing services have been settled on as a new type of public transportation owing to their enhanced convenience, expanded awareness of practical consumption patterns, the inspiration for environmental conscientiousness, and the diffusion of smart phones following the economic crisis. With development of the market, many people have started using such services. However, security is still an issue. Damage is expected since IDs and passwords are required for log-in when renting and controlling the vehicles. The protocol suggested in this study uses bio-information, providing an optimized service, and convenient (but strong) authentication with various service-provider clouds registering car big data about users through brokers. If using the techniques suggested here, it is feasible to reduce the exposure of the bio-information, and to receive service from multiple service-provider clouds through one particular broker. In addition, the proposed protocol reduces public key operations and session key storage by 20% on mobile devices, compared to existing car-sharing platforms, and because it provides convenient, but strong, authentication (and therefore constitutes a secure channel), it is possible to proceed with secure communications. It is anticipated that the techniques suggested in this study will enhance secure communications and user convenience in the future car-sharing-service cloud environment.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.1
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• pp.13-17
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• 1983

This experiment was carried out in order to know the relationship between morphological characters and dry matter yield at vegetative growth stage in Meadow fescue grown under plant basis. 1. The dry weight of a plant (PW) indicated positive significant correlation with plant height (pH), leaf area (LA) and stem area (SA). It means that increase in dry of a plant was resulted from interactions among above morphological characters. 2. Stem area (SA) is an important morphological character for increasing the dry weight of a plant. 3. The varieties could be classified into 3 types based on plant type index (PTI, dry weight of a plant/ (no. of tiller)$^2$), it were M in tiller weight type, Leto, First and Trader in medium type and, Bundy and Tammisto in tiller number type, respectively. 4. The variety with tiller weight type had more havier tiller and larger stem thickness than those of variety with tiller number type. But, tiller number type showed higher plant height. 5. In order to obtain the highest yield in tiller weight type, there were necessary to increasing the number of tillers and higher plant height.

• Proceedings of the Korea Contents Association Conference
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• 2009.05a
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• pp.405-409
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• 2009

There are many types of walking exercise. We have choice the way according to the walking exercise purpose. Nordic walking(NW) is one of walking types with nordic poles. Also, power walking(PW) has motion of large swing the arm in walking, and dumbbell walking(DW) way is walking with 3-pound dumbbell. This study compared the physiological response(heart rate, energy expenditure) of general walking(GW) to another types(nordic, power, and 3-pound hand weights walking way). Seven apparently male health volunteers between the ages 19 and 24 years participated. Each complete a treadmill test. The tests were assigned randomly, as submaximal walking trials on separate days. Each walking trial was conducted on a level treadmill, for 40 minutes(3-5mile/hour 5min warm-up, 6mile/hour speed for 15min walking and 7mile/hour speed for 15min Jogging exercise, and 5-3mile/hour cool down 5min), at an same pace. Heart rate in beats per minute(bpm), and energy expenditure in kcal per minute(kcal/min) were recorded each minute. Results between trials were compared using repeated measures analysis of variance and Tukey's post hoc tests. In slow walking, it was found that walking with 3-pound hand weight way resulted in and average of ($127.8{\pm}8.27bpm$) the highest score HR, Caloric expenditure($85.4{\pm}14.51kcal/min$), responses compared to regular walking way($117.4{\pm}7.27bpm$ and $70.4{\pm}10.99kcal/min$). Nordic walking way($121.4{\pm}11.74bpm$, and $77.0{\pm}16.83kcal/min$) is second, power walking way($118.5{\pm}9.98bpm$, and $68.7{\pm}20.62kcal/min$) is next. In fast walking, it was found that walking way with 3-pound hand weight resulted in and average of ($160.1{\pm}8.72bpm$) the highest score HR, caloric expenditure($126.1{\pm}13.86kcal/min$), responses compared to regular walking way($148.4{\pm}11.94bpm$, and $109.0{\pm}4.70kcal/min$). Nordic walking way($156.7{\pm}10.82bpm$, and $113.5{\pm}14.51kcal/min$) is second, power walking way($149.7{\pm}12.56bpm$, and $109.2{\pm}17.64kcal/min$) is next. Thus, it is the unavoidable conclusion that, comparing with general walking, 3-pound hand weight walking, nordic walking, and power walking methods have the advantage of high exercise intensity and energy expenditure to meet the purpose of performers without the problem. Furthermore, 3-pound hand weight walking ways were proved to be a useful aerobic exercise method as whole body that achieves high-energy efficiency. To this extent, 3-pound hand weight walking ways can be recommended as a continuous and regulative aerobic exercise for some people.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2002.04a
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• pp.41-47
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• 2002

감 과실(Diospyros kaki folium)은 아열대로부터 온대에 이르는 넓은 지역에서 재배되고 우리나라에서는 고래로부터 중요한 과실의 하나이다. 감은 예로부터 화상, 동상, 해독 및 지혈 등의 치료에 널리 이용되어져 왔으며 특히 곶감꼭지는 시체(枾滯)라 하여 달여서 먹으면 딸꾹질을 멎게 하는데 특효가 있다고 알려져 있다. $\ulcorner$본초비효$\lrcorner$ 에서는 생감을 깍아 말린 곶감은 숙혈을 없애고, 폐열, 혈토, 구역질, 장풍과 치질을 다스리는데 쓰인다고 하였다. 또한 감은 비타민 C의 함량이 많아 감을 먹으면 감기 예방에 좋다고 알려져 왔으며 주로 생식용으로 이용되어져 왔으나 최근 감을 이용한 다양한 가공제품 및 새로운 기능성 식품의 개발을 위한 연구가 활발히 이루어지고 있다. 감의 국내 총 생산량의 약60% 이상이 영남 지방에서 집중되어 재배 생산되고 잇으며 감과실의 비중은 다른 어느 지방보다 크다고 하겠다. 감은 단감과 떫은감이 있는데 단감은 주로 생과로 이용되고 있으며 떫은감은 떫은 맛을 가지기 때문에 생과로서 이용하는데 어려움이 있다. 상주는 백미, 누애고치, 곶감 등 희게 보이는 특산물이 유명한 삼백(三白)의 고장으로 미곡 생산량 전국 9위, 떫은감 2위, 곶감은 저눅 1위, 배는 2위, 사과 5위, 포도 4위를 점유하는 농업의 비중이 매우 높은 지역으로 농산물 시장 개방 확대와 과잉생산에 따른 가격하락의 피해를 예상된다. 종래 곶감의 위생적 문제점을 보완하고 공장 규모로 생산된, 품질이 규격화되고 유통기한이 설정된 고품질 전통 곶감의 제조 및 이에 따른 기술개발이 시급히 요구된다.idin C-1-3'-3" -3/'S _0-trigallate 즉, gallate가 붙은 호합물에서100rM의 농도에서 66%와 63%의 강한 저해효과를 나타났다. Tyrosinase 저해활성을 측정한 결과는pocyanidin C-1-3'-3" -3.'S _0-trigallate는 100rM에서 70%의 강한 저해효과를 나타냈으며,epigallocatechin-(4$\beta$$\longrightarrow$8)-epigallo-catechin-(4$\beta$$\longrightarrow$8)-catechin는 51%의 저해효과를 나타내었다. 산업적응용을 위해 분획한 폴리페놀군은 미백효과 검증실험인 tyrosinase 저해율 측정평가에서 폴리페놀 함량이 가장 높은 Fraction 111의 경우 Sooppm에서 74.2%의 높은 저해율을 나타내었다. 항산화력 실험에서는500pw1이상에서 강한 활성능을 보인 SOD 유사활성능을 제외한 나머지 DPPH와 xanthine oxidase 저해효과에서는 Fraction II와III 모두가50ppm이상에서 80% 이상의 높은 유리라디칼 소거능력을 나타내었다. 그리고 각 Fraction별 항균력 측정 결과 Fraction 르와 111이 우수하게 나타났고 항균활성은 그람음성균보다 그람양성균에서 효과적이었으며, 농도별 항균력시험 결과 농도가 증가할수록 비례하여 저해율도 증가함을 알 수 있었다. 첨가농도를 달리하여 미생물의 생육도를 측정한 결과, fraction II磎꼭\ulcorner경우 그람양성균에 대해 500 ppm 이상에서 뚜렷한 증식억제효과를 나타내었다.

• Korean Journal of Microbiology
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• v.31 no.3
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• pp.245-254
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• 1993

Distribution and variation of bacterial densities of heterotrophic plate count (HPC) and Enterobacteriaceae in the water supply systems comprising raw, treated, and three tap water samples of a water treatment plant in Seoul were studied 23 times from 1991 to 1992. HPC bacteria of raw. treated, and tap waters on $R_{2}A$ agar media were at a density of $1.22{\times}10^{3} to 3.05{\times}10^{5}$, $1.50{\times}10^{1} to 4.29{\times}10^{3}$ and 2 to $5.41{\times}10^{3}$ cfu/ml, respectively. Densities of Enterobacteriaceae in raw, treated, and tap waters on mENDO-LES agar media ranged from 0.] to 8200 cfu/ml, 0 to 17.5 cfu/JOO mI. and 0 to 47.5 cfu/IOO ml, respectively. Injured Enterobacteriaceae of treated and tap waters on m-T7 agar media were at a density of o to 27 and 0 to 35 cfu/100 mI. These results showed that the density of bacteria in the treated water outflowing from the water plant significantly increased as the water flowed along the distribution sytems, which is so-called bacterial regrowth. The predominant bacteria] types in the water supply system were Pw'udomonas and Acinerobacter. In raw water, the ratio of Pseudomonas was higher than that of Acinetobaeter, but in treated and tap waters. both ratios were reversed. The most predominant species of Enterobacteriaceae was Enterobacter agglomerans. Some species such as Citrobacter freundii. Escherichia coli. Klebsiella pneumoniae. and Shigella dysenteriae which are opportunistic pathogens or pathogens were not found in the treated water but additionally detected in tap waters.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.2
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• pp.75-86
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• 2003

The purpose of this study was to evaluate their mechanical properties after laser-welding or soldering of precious and non-precious dental alloys. For this study, 30 Co-Cr alloy specimens, 15 gold alloy specimens, 15 palladium alloy specimens were casted and seperated on the middle area. 15 sperated Co-Cr specimens and 15 seperated gold alloy specimens were laser welded (GW Group). 15 sperated Co-Cr specimens and 15 sperated gold alloy specimens were soldered by coventional soldering method (GS Group). 15 sperated Co-Cr specimens and 15 seperated palladium alloy specimens were laser welded (PW Group). 15 sperated Co-Cr specimens and 15 sperated palladium alloy specimens were soldered by coventional soldering method (PS Group). Tensile strength, 0.2% yield strength, % elongation were recorded in nine specimens of each group. Bending strength were record in six specimens of each group. These data for four groups were subjected to a two-way analysis of variance(ANOVA). The fracture locations, fractured surfaces were examined by SEM(scanning electron microscope). The results were as following: 1) In the same alloy combination, the tensile strength and 0.2% yield strength and of the laser welded group with same metal combination were significantly less than soldered groups(p<0.05). 2) In the combination of Co-Cr/Palladium, the bending strength of laser welded group were significantly less than that of soldered groups(p<0.05). In the combination of Co-Cr/Gold, the bending strength of laser welded group were significantly higher than that of soldered groups(p<0.05). 3) In the same method of joint, the tensile strength and 0.2% yield strength and bending strength of the Co-Cr/gold were significantly higher than Co-Cr/palladium(p<0.05). 4) There was no significantly statistical difference between each group in the % elongation(p>0.05). 5) The fracture of the laser welded specimens occured in the welding area and a large void was observed at the center of the fracture surface. 6) The fracture of the soldered specimens occured also inthe soldered area and many porpsities were showed at the fracture sites.