• Title/Summary/Keyword: Biological Engineering

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Temperature Compensation of Complex Permittivities of Biological Tissues and Organs in Quasi-Millimeter-Wave and Millimeter-Wave Bands

  • Sakai, Taiji;Wake, Kanako;Watanabe, Soichi;Hashimoto, Osamu
    • Journal of electromagnetic engineering and science
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    • v.10 no.4
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    • pp.231-236
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    • 2010
  • This study proposes a temperature compensation method of the complex permittivities of biological tissues and organs. The method is based on the temperature dependence of the Debye model of water, which has been thoroughly investigated. This method was applied to measured data at room temperature for whole blood, kidney cortex, bile, liver, and heart muscle. It is shown that our method can compensate for the Cole-Cole model using measured data at 20 $^{\circ}C$, given the Cole-Cole model based on measured data at 35 $^{\circ}C$, with a root-mean-squared deviation of 3~11 % and 2~6 % for the real and imaginary parts of the complex permittivities, respectively, among the measured tissues.

Chiral Pool Synthesis of N-Cbz-cis-(3R,4R)-3-methylamino-4-methylpiperidine from L-Malic acid

  • Hao, Bao-Yu;Liu, Jin-Qiang;Zhang, Wei-Han;Chen, Xin-Zhi
    • Bulletin of the Korean Chemical Society
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    • v.34 no.5
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    • pp.1371-1377
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    • 2013
  • A new synthetic route to N-Cbz-cis-(3R,4R)-3-methylamino-4-methylpiperidine, key intermediate for CP-690,550, was disclosed with L-malic acid as the chiral pool starting material. The title compound was obtained in 16 steps with a total yield of 26% and more than 98% ee.

Tissue and Immune Responses on Implanted Nanostructured Biomaterials

  • Khang, Dong-Woo;Kang, Sang-Soo;Nam, Tae-Hyun
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2009.05a
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    • pp.47.1-47.1
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    • 2009
  • Nanostructured biomaterials have increased those potential for utilizing in many medical applications. In this study, benefit of nanotechnology for the response with biological targets will be described in terms of size, effective surface area and surface energy (physical aspect). Also, correlations between physical and biological interactions (greater protein adsorption on nano surface roughness) will be discussed for understanding biocompatibility of nanostructured biomaterials including carbon nanotube composites and nanostructured titanium surfaces. In the application parts, various major tissue cells, such as bone, cartilage, vascular and bladder cell responses will be discussed with suggested nanomaterials. Lastly, immune responses with macrophage (adhesion and several major cytokines) on nanostructured biomaterials will be described for evasive immune response.

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Preparation of Mesoporous SiCBN Ceramic Templated by Mesoporous Carbon

  • Nghiem, Quoc Dat;Ryoo, Hyang-Im;Kim, Dong-Pyo
    • Journal of the Korean Ceramic Society
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    • v.44 no.7
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    • pp.358-361
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    • 2007
  • Well-ordered mesoporous SiCBN ceramics have been successfully synthesized by infiltrating a polymeric precursor, which was prepared from borazine and 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane via a hydroboration reaction, into a mesoporous carbon (CMK-3) as a hard template. This was followed by pyrolysis at $1400^{\circ}C$ under nitrogen gas and subsequent oxidative removal of the carbon template without chemical etching. The prepared mesoporous SiCBN ceramic was characterized by a small-angle XRD, TEM, and BET surface area. The resulting mesoporous SiCBN ceramic revealed a BET surface area of $275 m^2g^{-1}$ and a pore volume of $0.8 cm^3 g$ with no crystallization.

Cultivation of Digitalis lanata Cell Suspension in an Aqueous Two-Phase System

  • Choi, Yeon-Sook;Lee, Sang-Yoon;Kim, Dong-Il
    • Journal of Microbiology and Biotechnology
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    • v.9 no.5
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    • pp.589-592
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    • 1999
  • Suspension cultures of Digitalis lanata were successfully performed in an aqueous two-phase system (ATPS) of 4.5% polyethylene glycol (PEG) 20,000 and 2.8% crude dextran. Cell growth in the medium containing an individual ATPS-forming polymer was inhibited due to the toxicity of PEG and a high viscosity of dextran. Formation of ATPS supported cell growth by showing a considerably decrease in viscosity and partitioning of cells into a PEG-lean dextran phase. It was found that an aqueous two-phase cultivation of plant cells in a stirred tank bioreactor could be successfully applied.

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Metabolic Characterization of Lactic Acid Bacterium Lactococcus garvieae sk11, Capable of Reducing Ferric Iron, Nitrate, and Fumarate

  • Yun, Su-Hee;Hwang, Tae-Sik;Park, Doo-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.17 no.2
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    • pp.218-225
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    • 2007
  • A lactic acid bacterium capable of anaerobic respiration was isolated from soil with ferric iron-containing glucose basal medium and identified as L. garvieae by using 16S rDNA sequence homology. The isolate reduced ferric iron, nitrate, and fumarate to ferrous iron, nitrite, and succinate, respectively, under anaerobic $N_2$ atmosphere. Growth of the isolate was increased about 30-39% in glucose basal medium containing nitrate and fumarate, but not in the medium containing ferric iron. Specifically, metabolic reduction of nitrate and fumarate is thought to be controlled by the specific genes fnr, encoding FNR-like protein, and nir, regulating fumarate-nitrate reductase. Reduction activity of ferric iron by the isolate was estimated physiologically, enzymologically, and electrochemically. The results obtained led us to propose that the isolate metabolized nitrate and fumarate as an electron acceptor and has specific enzymes capable of reducing ferric iron in coupling with anaerobic respiration.

Seasonal Assessment of Biomass and Fatty Acid Productivity by Tetraselmis sp. in the Ocean Using Semi-Permeable Membrane Photobioreactors

  • Kim, Z-Hun;Park, Hanwool;Lee, Choul-Gyun
    • Journal of Microbiology and Biotechnology
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    • v.26 no.6
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    • pp.1098-1102
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    • 2016
  • A green microalga, Tetraselmis sp., was cultivated in the coastal seawater of Young-Heung Island using semi-permeable membrane photobioreactors (SPM-PBRs) in different seasons. The microalgae in the SPM-PBRs were able to grow on nutrients diffused into the PBRs from the surrounding seawater through SPMs. The biomass productivity varied depending on the ion permeabilities of the SPMs and environmental conditions, whereas the quality and quantity of fatty acids were constant. The temperature of seawater had a greater influence than solar radiation did on productivity of Tetraselmis sp. in SPM-PBRs. SPM-PBRs could provide technologies for concurrent algal biomass and fatty acids production, and eutrophication reduction in the ocean.

Analyses of Thermodynamic Vaporization Behaviour and Voloxidaion Conditions for Metal Oxides (금속산화물의 열역학적 휘발 거동 및 휘발 산화 공정의 조건 분석)

  • Lee, Young Woo;Park, So Young;Park, Byung Heung
    • Journal of Institute of Convergence Technology
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    • v.3 no.2
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    • pp.7-10
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    • 2013
  • Metal oxides are known as stable materials during a thermal treatment. However, some oxides are readily evaporated at high temperatures. A voloxidation process is a head-end process for a pyroprocessing dealing with spent nuclear fuels (SF). In SFs, fission productions are in the form of oxides and some of them would be evaporated during the voloxidation process. Therefore, it is of importance to analyse the vapor pressures of metal oxides so that the material flows throughout the pyroprocessing could be estimated. In this work, vapor pressures of relevant metal oxides were calculated and presented to draw a baseline on the material flow of the pyroprocessing.

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Nondestructive Techniques for Quality Inspection of Fruits and Vegetables

  • Young J. Han;Cho, Young-Jin;Wayne S. Rial;Wade E. Lambert
    • Preventive Nutrition and Food Science
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    • v.2 no.3
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    • pp.269-279
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    • 1997
  • Various nondestructive technologies for quality inspection of fruits and vegetables were reviewed through published literatures and selected agricultural databases. These technologies were grouped into nine categories, including acoustic response, dielectric response, machine vision, magnetic response, mechanical vibration response, microwave response, optical properties, and other possible sensing technologies. Their principles and characteristics were investigated and these technologies were presented with their current and potential applications. The link of appropriate nondestructive technologies with common principal quality parameters of fruits and vegetables was summarized.

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Lung Sound Classification Using Hjorth Descriptor Measurement on Wavelet Sub-bands

  • Rizal, Achmad;Hidayat, Risanuri;Nugroho, Hanung Adi
    • Journal of Information Processing Systems
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    • v.15 no.5
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    • pp.1068-1081
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    • 2019
  • Signal complexity is one point of view to analyze the biological signal. It arises as a result of the physiological signal produced by biological systems. Signal complexity can be used as a method in extracting the feature for a biological signal to differentiate a pathological signal from a normal signal. In this research, Hjorth descriptors, one of the signal complexity measurement techniques, were measured on signal sub-band as the features for lung sounds classification. Lung sound signal was decomposed using two wavelet analyses: discrete wavelet transform (DWT) and wavelet packet decomposition (WPD). Meanwhile, multi-layer perceptron and N-fold cross-validation were used in the classification stage. Using DWT, the highest accuracy was obtained at 97.98%, while using WPD, the highest one was found at 98.99%. This result was found better than the multi-scale Hjorth descriptor as in previous studies.