• Title/Summary/Keyword: Biological Engineering

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A Study on Optical Properties in Biological Tissue Using A Photon Path Diffusion Model (광 항적경로 모델을 이용한 피하조직에서의 광 특성에 관한 연구)

  • 임현수
    • Journal of Biomedical Engineering Research
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    • v.15 no.3
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    • pp.265-274
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    • 1994
  • This paper proposes a method of noninvasive reflectance light to measure the blood fractional volume (Vb) and oxygen saturation ($SO_2$) of biological tissue. We chose the red light of 660nm and infrared light of 880nm. In Vivo reflectance data were obtained by the physiological changes front the surface of the skin over the calf in human subject. The reflected light intensity from different layers within a biological tissue was measured by specially designed reflectometer to apply photon path diffusion model. The collected data represent the changes of blood (ractional volume and oxygen saturation at each reflected light wavelengths. The data evaluation was assessed by examining the slopes of the plotted indices for the changes in oxygen saturation and blood (ractional volume. The results presented in this paper claim that light reflectance can separately discriminate the change of blood volume and that of oxygenation in muscle and also in skin.

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Volatile Fatty Acids Production During Anaerobic and Aerobic Animal Manure Bio-treatment

  • Hong, J.H.
    • Journal of Animal Environmental Science
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    • v.13 no.3
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    • pp.219-232
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    • 2007
  • Odors from manures are a major problem for livestock production. The most significant odorous compounds in animal manure a.e volatile fatty acids(VFAs). This work reviews the VFAs from the anaerobic sequencing biofilm batch reactor(ASBBR), anaerobic sequencing batch reactor(ASBR), solid compost batch reactor(SCBR), and aerobic sequencing batch reactor(SBR) associated with the animal manure biological treatment. First, we describe and quantify VFAs from animal manure biological treatment and discuss biofiltration for odor control. Then we review certain fundamentals aspects about Anaerobic and aerobic SBR, composting of animal manure, manure compost biofilter for odorous VFAs control, SBR for nitrogen removal, and ASBR for animal wastewater treatment systems considered important for the resource recovery and air quality. Finally, we present an overview for the future needs and current experience of the biological systems engineering for animal manure management and odor control.

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Influence of Oenococcus oeni Inoculation Time on the Quality of MBA Wine (Oenococcus oeni의 접종 시기가 국내 MBA 포도의 와인 품질에 미치는 영향)

  • Lee, Jung-Chang;Choi, Yong-Keun;Yoon, Jae-Yoon;Kim, Hyung Joo;Yi, Dong-Hee;Jung, Seok-Tae;Lee, Won-Jae
    • Culinary science and hospitality research
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    • v.21 no.6
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    • pp.229-241
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    • 2015
  • This study investigated the effect of co-inoculation with Oenococcus oeni on the final quality of domestic MBA(Muscat Baily A) wine. For experiment five types of wine samples were classified for the experiment and the results are as follows; co-inoculation with Oenococcus oeni concurrently (i.e., the S+O.Co sample) reduced wine production time and facilitated the production offor high quality wine. Compared to the other samples, S+O.Co wine had a higher number of viable Oenococcus oeni cells and a rapid reduction in malic acid content although its lactic acid content increased more rapidly. Concurrent inoculation with yeast and Oenococcus oeni allowed malolactic fermentation and alcohol fermentation to be completed at the same time within 14 to 16 days. Therefore, this study showed that co-inoculation of S+O.Co wine with Oenococcus oeni had an effect through quality improvement, reduced wine making time, and increased productivity.

Molecular Level Detection of Heavy Metal Ions Using Atomic Force Microscope (원자간인력현미경을 이용한 분자수준의 중금속 이온 검출)

  • Kim, Younghun;Kang, Sung Koo;Choi, Inhee;Lee, Jeongjin;Yi, Jongheop
    • Clean Technology
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    • v.11 no.2
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    • pp.69-74
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    • 2005
  • A metal ion detector with a submicron size electrode was fabricated by field-induced AFM oxidation. The square frame of the mesa pattern was functionalized by APTES for the metal ion detection, and the remaining portion was used as an electrode by the self-assembly of MPTMS for Au metal deposition. The conductance changed with the quantity of adsorbed copper ions, due to electron tunneling between the mobile and surface electrodes. The smaller electrode has a lower limit of detection due to the enhancement in electron tunneling through metal ions that are adsorbed between the conductive-tip (mobile) and the surface (fixed) electrode. This two-electrode system immobilized with different functional groups was successfully used in the selective adsorption and detection of target materials.

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Nano Ceramic Coating on Polypropylene Separator for Safety-Enhanced Lithium Secondary Battery (고안전성 리튬이차전지 구현을 위한 나노 세라믹 코팅 분리막 제조 및 전기화학특성 분석)

  • Lee, Jungmo;Jeon, Hyunkyu;Han, Taeyeong;Ryou, Myung-Hyun;Lee, Yong Min
    • Journal of the Korean Electrochemical Society
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    • v.20 no.2
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    • pp.41-48
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    • 2017
  • Herein, we have fabricated an ultrathin aluminum oxide ($Al_2O_3$) coated PP separator by using a RF sputter deposition process. Approximately 20 nm thickness coating layer on the bare PP separator was formed at the power of 55 W for 2 minutes without thermal damage. Whereas only permeability of the coated separator was degraded slightly, other properties such as thermal stability, uptake amount of liquid electrolyte, and ionic conductivity were improved comparing to the bare PP separator. As a result, an only 20-nm-thick $Al_2O_3$ coating layer could improve the rate capability compared with a bare PP separator under a high current density.

Ethanol Production with Glucose/Xylose Mixture by Immobilized Pichia stipitis (고정화 Pichia stipitis 를 이용한 글루코오스/자일로오스 혼합당으로부터 에탄올 생산)

  • Shin, Hyun-Seok;Kang, Seong-Woo;Lee, Sang-Jun;Jang, Eun-Ji;Suh, Young-Woong;Kim, Seung-Wook
    • KSBB Journal
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    • v.25 no.4
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    • pp.351-356
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    • 2010
  • To increase the production of ethanol by using sugar from lignocellulosic biomass, pentose and hexose have to be fermented simultaneously by yeast. The effects of mixed sugar and nitrogen on ethanol production by immobilized Pichia stipitis KCCM 12009 were investigated. When optimal mixed sugar and nitrogen concentration were 5% (Glucose/Xylose = 3:1) and 1%, respectively, ethanol concentration produced by immobilized P. stipitis was 19-20 g/L. In repeated fed-batch by immobilized P. stipitis, all glucose was consumed very quickly at 1-3% mixed sugar concentration. But, xylose consumption was decreased as the mixed sugar concentration increased. Also, ethanol (5.6 g/L) was stably produced and ethanol production rate was 0.13 g/$L{\cdot}h$ in immobilized cell reactor (ICR) with 1% mixed sugar (Glucose/Xylose = 3:1) as feeding media.

Specific Light Uptake Rate Can be Served as a Scale-Up Parameter in Photobioreactor Operations

  • Lee, Ho-Sang;Kim, Z-Hun;Jung, Sung-Eun;Kim, Jeong-Dong;Lee, Choul-Gyun
    • Journal of Microbiology and Biotechnology
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    • v.16 no.12
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    • pp.1890-1896
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    • 2006
  • Lumostatic operation for cultivation of Haematococcus pluvialis was assessed to test the scale-up strategy of photobioreactors. Lumostatic operation is a method of maintaining a proper light condition based on the specific light uptake rate ($q_e$), by cells. Lumostatic operations were performed in 0.4-, 2-, 10-, and 30-1 scale bubble column photobioreactors and the results were compared with cultures illuminated with constant light intensity. Significant differences were observed in the maximal cell concentrations obtained from 0.4-, 2-, 10-, and 30-1 scale photobioreactors under constant light intensity, yielding the maximal cell concentrations of $2.8{\times}10^5$, $2.2\times10^5$, $1.5\times10^5$, and $1.1\times10^5$ cells/ml, respectively. The maximal cell concentration in a 0.4-1 photobioreactor under lumostatic operation was $4.3\times10^5$ cells/ml. Furthermore, those in 2-, 10-, and 30-1 scale photobioreactors were about the same as that in the 0.4-1 photobioreactor. The results suggest that lumostatic operation with proper $q_e$ is a good strategy for increasing the cell growth of Haematococcus pluvialis compared with a constant supply of light energy. Therefore, lumostatic operation is not only an efficient way to achieve high cell density cultures with minimal power consumption in microalgal cultures but it is also a perfect parameter for the scale-up of photobioreactors.

The Within-Host Population Dynamics of Normal Flora in the Presence of an Invading Pathogen and Antibiotic Treatments

  • Kim, Jung-Mo;Lee, Dong-Hwan;Song, Yoon-Seok;Kang, Seong-Woo;Kim, Seung-Wook
    • Journal of Microbiology and Biotechnology
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    • v.17 no.1
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    • pp.146-153
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    • 2007
  • A mathematical competition model between normal flora and an invading pathogen was devised to allow analysis of bacterial infections in a host. The normal flora includes the various microorganisms that live on or within the host and act as a primary human immune system. Despite the important role of the normal flora, no mathematical study has been undertaken on models of the interaction between it and invading pathogens against a background of antibiotic treatment. To quantify key elements of bacterial behavior in a host, pairs of nonlinear differential equations were used to describe three categories of human health conditions, namely, healthy, latent infection, and active infection. In addition, a cutoff value was proposed to represent the minimum population level required for survival. The recovery of normal flora after antibiotic treatment was also included in the simulation because of its relation to human health recovery. The significance of each simulation parameter for the bacterial growth model was investigated. The devised simulation showed that bacterial proliferation rate, carrying capacity, initial population levels, and competition intensity have a significant effect on bacterial behavior. Consequently, a model was established to describe competition between normal flora and an infiltrating pathogen. Unlike other population models, the recovery process described by the devised model can describe the human health recovery mechanism.

Effects of Quorum Quenching on the Microbial Community of Biofilm in an Anoxic/Oxic MBR for Wastewater Treatment

  • Jo, Sung Jun;Kwon, Hyeokpil;Jeong, So-Yeon;Lee, Sang Hyun;Oh, Hyun-Suk;Yi, Taewoo;Lee, Chung-Hak;Kim, Tae Gwan
    • Journal of Microbiology and Biotechnology
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    • v.26 no.9
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    • pp.1593-1604
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    • 2016
  • Recently, bacterial quorum quenching (QQ) has been proven to have potential as an innovative approach for biofouling control in membrane bioreactors (MBRs) for advanced wastewater treatment. Although information regarding the microbial community is crucial for the development of QQ strategies, little information exists on the microbial ecology in QQ-MBRs. In this study, the microbial communities of biofilm were investigated in relation to the effect of QQ on anoxic/oxic MBRs. Two laboratory-scale MBRs were operated with and without QQ-beads (QQ-bacteria entrapped in beads). The transmembrane pressure increase in the QQ-MBRs was delayed by approximately 100-110% compared with conventional- and vacant-MBRs (beads without QQ-bacteria) at 45 kPa. In terms of the microbial community, QQ gradually favored the development of a diverse and even community. QQ had an effect on both the bacterial composition and change rate of the bacterial composition. Proteobacteria and Bacteroidetes were the most dominant phyla in the biofilm, and the average relative composition of Proteobacteria was low in the QQ-MBR. Thiothrix sp. was the dominant bacterium in the biofilm. The relative composition of Thiothrix sp. was low in the QQ-MBR. These findings provide useful information that can inform the development of a new QQ strategy.

Rumen Degradability and Small Intestinal Digestibility of the Amino Acids in Four Protein Supplements

  • Wang, Y.;Jin, L.;Wen, Q.N.;Kopparapu, N.K.;Liu, J.;Liu, X.L.;Zhang, Y.G.
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.2
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    • pp.241-249
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    • 2016
  • The supplementation of livestock feed with animal protein is a present cause for public concern, and plant protein shortages have become increasingly prominent in China. This conflict may be resolved by fully utilizing currently available sources of plant protein. We estimated the rumen degradability and the small intestinal digestibility of the amino acids (AA) in rapeseed meal (RSM), soybean meal (SBM), sunflower seed meal (SFM) and sesame meal (SSM) using the mobile nylon bag method to determine the absorbable AA content of these protein supplements as a guide towards dietary formulations for the dairy industry. Overall, this study aimed to utilize protein supplements effectively to guide dietary formulations to increase milk yield and save plant protein resources. To this end, we studied four cows with a permanent rumen fistula and duodenal T-shape fistula in a $4{\times}4$ Latin square experimental design. The results showed that the total small intestine absorbable amino acids and small intestine absorbable essential amino acids were higher in the SBM (26.34% and 13.11% dry matter [DM], respectively) than in the SFM (13.97% and 6.89% DM, respectively). The small intestine absorbable Lys contents of the SFM, SSM, RSM and SBM were 0.86%, 0.88%, 1.43%, and 2.12% (DM basis), respectively, and the absorbable Met contents of these meals were 0.28%, 1.03%, 0.52%, and 0.47% (DM basis), respectively. Among the examined food sources, the milk protein score of the SBM (0.181) was highest followed by those of the RSM (0.136), SSM (0.108) and SFM (0.106). The absorbable amino acid contents of the protein supplements accurately reflected protein availability, which is an important indicator of the balance of feed formulation. Therefore, a database detailing the absorbable AA should be established.