• Title/Summary/Keyword: Biological Engineering

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In vitro antibacterial availability of bioconverted ${\gamma}-linolenic$ acid

  • Kang, Sun-Chul;Shin, Seung-Yong;Kim, Hak-Ryul
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.307-308
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    • 2005
  • Bioconverted hydroxy fatty acid from ${\gamma}-linolenic$ acid showed antibacterial activity against Gram-positive bacteria such as Bacillus subtilis (ATCC 6633), Listeria monocytogenes (ATCC 19166), Staphylococcus aureus (ATCC 6538) and S. aureus (KCTC 1916) and one Gram-negative bacteria, Pseudomonas aeruginosa (KCTC 2004) with MIC ranging from 250 to $750\;{\mu}g/ml$ against five of eleven bacteria tested.

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Synthesis and characterization of starch$^Na+$-montmorillonite clay nanocomposites

  • Na, Seong-Ki;Park, Jong-Shin
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10a
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    • pp.67-68
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    • 2003
  • Native corn starch and montmorillonite caly nanocomposites were prepared using the glycerol as the plasticizer. These were characterized by mechanical analysis, X-ray diffraction, infrared spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The tensile strength increased with the clay content to a maximum point and then decreased due to gapping between the two phases. Dispersion of the layered silicate within the starch was verified using X-ray diffraction pattern. Examination of these materials by scanning electron showed that intercalates have good wetting to the starch surface.

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Quantitative Counting of Bifidobacterium spp. in a Sample Mixed with Lactobacillus acidophilus

  • Park, Young-Min;So, Jae-Seong
    • Journal of Microbiology and Biotechnology
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    • v.8 no.2
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    • pp.182-184
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    • 1998
  • PCR was used for quantitative counting of Bifidobacterium spp. in a sample mixed with Lactobacillus acidophilus using two primer sets; one set for universal priming and the other set for Bifidobacterium specific priming. DNA products from two independent PCRs with DNA extracted from the mixed sample were found to be easily distinguishable from each other by agarose gel electrophoresis. The concentrations of PCR products correlated with the total number of bacteria and with the number of Bifidobacterium spp. present in the sample.

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Facile Approach to Magnetic Carbon Nanoparticles using an Iron-Doped Polymer Precursor

  • Yoon, Hyeon-Seok;Jang, Jyong-Sik
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.283-283
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    • 2006
  • Multigram-scale product exclusively containing magnetic carbon nanoparticles (MNCPs) with uniform size was successfully fabricated without a specific separation process. The iron-doped PPy nanoparticles were synthesized by micelle templating and used as the carbon precursor in order to generate MCNPs. The magnetic carbon nanoparticles possessed a microporous structure and exhibited ferromagnetic properties at room temperature. This approach may be an effective alternative to generate magnetic carbon nanoparticles against the conventional arc-discharge technique.

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Inhibitory Effect of Buthus martensi Karsch Extracts on ${\alpha}$-Glucosidase Enzyme

  • Kim, Eun-Ok;Kim, Shin-Duk
    • International Journal of Industrial Entomology and Biomaterials
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    • v.15 no.2
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    • pp.161-164
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    • 2007
  • While searching for ${\alpha}$-glucosidase inhibitors, the active compound was found in a methanol extract of Burthus martensi Kirsch. The separation of the active compound was performed using various chromatography methods and the physico-chemical properties of the purified compound were characterized. The compound showed very potent inhibitory activity against ${\alpha}-glucosidase$ with an $IC_{50}$ value of $5.3\;{\mu}g/ml$. Lineweaver-Burk plot indicated that its inhibition of ${\alpha}-glucosidase$ was competitive.

Micro-sized carbon with dimple patterns prepared using an electro-spray method

  • Park, Mi-Seon;Lee, Young-Seak
    • Carbon letters
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    • v.16 no.3
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    • pp.215-218
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    • 2015
  • Carbon micro particles with dimple patterns were produced by electro-spraying a solution of pitch in tetrahydrofuran. Particle formation depended on separation in an electrical field and volatilization of the solvent. More than 80% of the obtained carbon exhibited an average particle size of less than 50 μm. X-ray diffraction analysis suggests that the carbon with dimple patterns has increased crystallinity after heat treatment.

잡음동기형 표본화 제어기에 의한 전력선 잡음의 적응제거

  • Ko, Han-Woo;Kim, Won-Ky;Lee, Gun-Ki
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.117-124
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    • 1988
  • A new implementation of a noise tracking filter is prposed to eliminate time-varying 60 Hz noise and its harmonics and baselins wandering in biological signals. This technique was applied to ECG. Filter's notch frequency could track the power line frequency well and it showed much better characteristics than the conventional method.

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A Study of the Factors of Synchronization Model on Myocardial Cell Rhythms (심근세포의 동기리듬에 관한 공학적 연구)

  • 박민용
    • Journal of Biomedical Engineering Research
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    • v.5 no.1
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    • pp.33-38
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    • 1984
  • Biological rhythms are very important phenomena to generate, grow a living thing. However, the origin of rhythms are not disclosed completely until now. Eack myocardial cell has a natural rhythm of itself, and synchronization is happened when two cells are come in contact with each other. In this research, a simple synchronization model has been proposed and studied, refering to the physiological model. The changes of the synchronization rhythms in experimental results are compared with that of the model.

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