• 광산업정보
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• 통권62호
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• pp.63-65
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• 2011

• 천문학회보
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• 제30권1호
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• pp.59.1-59.1
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• 2005

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.956-957
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• 2005

• Journal of Microbiology and Biotechnology
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• 제21권12호
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• pp.1330-1335
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• 2011

N-Acyl homoserine lactones (AHLs) serve as the vital quorum-sensing signals that regulate the virulence of the pathogenic bacterium Erwinia carotovora. In the present study, an approach to efficiently restrain the pathogenicity of E. carotovora-induced soft rot disease is described. Bacillus thuringiensis-derived N-acyl homoserine lactonase (AiiA) was projected onto the surface of Pseudomonas putida cells, and inoculation with both strains was challenged. The previously identified N-terminal moiety of the ice nucleation protein, InaQ-N, was applied as the anchoring motif. A surface display cassette with inaQ-N/aiiA was constructed and expressed under the control of a constitutive promoter in P. putida AB92019. Surface localization of the fusion protein was confirmed by Western blot analysis, flow cytometry, and immunofluorescence microscopy. The antagonistic activity of P. putida MB116 expressing InaQ-N/AiiA toward E. carotovora ATCC25270 was evaluated by challenge inoculation in potato slices at different ratios. The results revealed a remarkable suppressing effect on E. carotovora infection. The active component was further analyzed using different cell fractions, and the cell surface-projected fusion protein was found to correspond to the suppressing effect.

• The Plant Pathology Journal
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• 제39권1호
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• pp.88-107
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• 2023

In the present investigation, bacterial isolates from infected apple trees causing apple canker during winter were studied in the northern Gyeongbuk Province, Korea. The pathogen was identified as Pseudomonas syringae pv. syringae (Pss) through various physiological and biochemical characterization assays such as BIOLOG, gas chromatography of fatty acid methyl esters, and 16S rRNA. Bioassays for the production of phytotoxins were positive for syringopeptin and syringomycin against Bacillus megaterium and Geotrichum candidum, respectively. The polymerase chain reaction (PCR) method enabled the detection of toxin-producing genes, syrB1, and sypB in Pss. The differentiation of strains was performed using LOPAT and GATTa tests. Pss further exhibited ice nucleation activity (INA) at a temperature of -0.7℃, indicating an INA⁺ bacterium. The ice-nucleating temperature was -4.7℃ for a non-treated control (sterilized distilled water), whereas it was -9.6℃ for an INA^- bacterium Escherichia coli TOP10. These methods detected pathogenic strains from apple orchards. Pss might exist in an apple tree during ice injury, and it secretes a toxin that makes leaves yellow and cause canker symptoms. Until now, Korea has not developed antibiotics targeting Pss. Therefore, it is necessary to develop effective disease control to combat Pss in apple orchards. Pathogenicity test on apple leaves and stems showed canker symptoms. The pathogenic bacterium was re-isolated from symptomatic plant tissue and confirmed as original isolates by 16S rRNA. Repetitive element sequence-based PCR and enterobacterial repetitive intergenic consensus PCR primers revealed different genetic profiles within P. syringae pathovars. High antibiotic susceptibility results showed the misreading of mRNA caused by streptomycin and oxytetracycline.

• 한국정보통신학회논문지
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• 제3권2호
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• pp.339-346
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• 1999

본 논문에서는 INMARSAT-C형 위성통신단발기의 수신단의 회로설계, 제작 및 특성측정을 수행하였다. INA-03184를 이용한 고이득증폭단은 양단 정합된 단일 증폭기 형태로 제작하였으며, 바이어스 안정화 저항을 사용하여 회로의 전압강하 및 전력손실을 가능한 줄이고 온도 안정성을 고려하여 Active 바이어스회로를 사용하였으며, 스퓨리어스를 감쇄시키기 위해서 저잡음증폭기와 고이득증폭단 사이에 대역통과 필터를 사용하였다 측정 결과, 사용 주파수 대역내에서 60 dB 이상의 이득, 44.83 dBc의 스퓨리어스 특성 및 1.8:1 이하의 입ㆍ출력 정재파비를 나타냄으로써 설계시 목표로 했던 사양을 만족시켰다.

• Journal of Microbiology and Biotechnology
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• 제24권3호
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• pp.379-385
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• 2014

The purpose of this study was to compare the ability of an engineered Escherichia coli to degrade chlorpyrifos (Cp) using an organophosphorus hydrolase enzyme, encoded in both Flavobacterium sp. ATCC 27551 or Pseudomonas diminuta, by employing the Lpp-OmpA chimera and the N-terminal domain of the ice nucleation protein as anchoring motifs. Tracing of the expression location of the recombinant protein using SDS-PAGE showed the presentation of OPH by both anchors on the outer membrane. This is the first report on the presentation of OPH on the cell surface by Lpp-OmpA under the control of the T7 promoter. The results showed cell growth in the presence of Cp as the sole source of energy, without growth inhibition, and with higher whole-cell activity for both cells harboring plasmids pENVO and pELMO, at approximately 10,342.85 and 10,857.14 U/mg, respectively. Noticeably, the protein displayed by pELMO was lower than the protein displayed by pENVO. It can be concluded that Lpp-OmpA can display less protein, but more functional OPH protein. These results highlight the high potential, of both engineered bacteria, for use in the bioremediation of pesticide-contaminated sources in the environment.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.521-524
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• 2009

신경자극반응 측정 플랫폼을 구현하는데 있어서 손가락 움직임을 감지하는 것이 중요한 요소로 작용하고 있다. 이것은 손가락의 움직임에 따라 신경자극과 근육반응이 달라지기 때문이다. 즉, 손가락의 움직임을 감지해서 신경 자극 Actuator 및 근육 반응 감지를 위한 H/W 개발이 필요한 것이다. 또한 임베디드 기반으로 가기위한 저전력 CPU를 사용하였다. H/W 구성은 isolation power부분, 정전류조절, High impedance INA, 증폭기부분이 있으며 Micro-controller에서는 stimulus mode 및 Current 의 상태를 통제하고, AD converter를 통해 얻어진 Low Data를 처리 시스템을 구현한다.

• 한국균학회지
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• 제50권4호
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• pp.255-262
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• 2022

In this study, the fungal strain KNUF-21-F39 was isolated from a declined apple tree (Malus domestica) in the Chungcheongbuk province in Korea. The strain KNUF-21-F39 presented a slow growth rate and a variety of macroconidia shapes and sizes ranging from ovoid to fusoid and 1- to 5-septate, primarily showing 3- and 4-septate, with "S" -shaped macroconidia rarely observed. The strain was identified based on morphological characteristics along with phylogenetic analysis performed using the internal transcribed spacer region (ITS) and partial sequences of translation elongation factor 1-α (tef1), RNA polymerase largest subunit (rpb1), and calmodulin (cal) genes. The fungal strain KNUF-21-F39 was identified as Fusarium diversisporum, which has not been previously reported in Korea. The ice nucleation activity (INA) of the strain was also evaluated, identifying the strain as positive for INA. This is the first report characterizing F. diversisporum as an IN-active fungal species.

• 대한치과보철학회지
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• 제55권1호
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• pp.9-17
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• 2017

목적: 내부 연결형과 외부 연결형의 임플란트에서 직선형과 경사형 지르코니아 지대주의 파절강도를 비교하였다. 재료 및 방법: 내부육각 연결형 임플란트 20개와 외부육각 연결형 임플란트 20개에, 기성 직선형 지르코니아 지대주와, $17^{\circ}$ 경사형 지르코니아 지대주를 10개씩 체결하였다. 시편은 연결 방식과 지대주 각도에 따라 4개의 군으로 나누었다: 내부 연결형/ 직선형 지대주, INS군; 내부 연결형/ 경사형 지대주, INA 군; 외부 연결형/ 직선형 지대주, EXS 군; 외부 연결형/ 경사형 지대주, EXA 군. 모든 시편은 만능시험기에서 1 mm/min의 crosshead speed로 $30^{\circ}$ 하중을 가했다. 지대주의 파절강도를 측정하고, 2-way ANOVA와 independent t-test로 통계처리 하였다(${\alpha}=.05$). 결과: 각 군의 평균파절강도는 다음과 같다: INS군, 955.91 N; INA군, 933.65 N; EXS군, 1267.20 N; EXA군, 1405.93 N. 외부 연결형이 내부 연결형에 비해 파절강도가 높았다(P < .001). 내부연결형(P = .747)과 외부 연결형(P = .222)에서 지대주 각도에 따른 파절강도는 차이가 없었다. 또한 내부 연결형 지대주는 육각 부위에서 수평 파절이 일어난 반면, 외부 연결형 지대주는 설측 치경부에서 파절되었다. 결론: 외부 연결형 지르코니아 지대주가 내부 연결형 지대주에 비해 파절 강도가 높았고, 직선형과 경사형 지르코니아 지대주의 파절강도는 차이가 없었다.