• Biomolecules & Therapeutics
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• v.17 no.3
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• pp.288-292
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• 2009

Interactions between tumor cells and the extracellular matrix (ECM) strongly influence tumor development, affecting cell survival, proliferation and migration. Fibronectin, a major component of ECM, has been shown to interact with integrins especially the ${\alpha}5{\beta}1$ integrin. Cell invasion and metastasis are often associated with matrix metalloproteinases (MMPs) which are capable of digesting the different components of the ECM and basement membrane. MMP-2 is produced as a latent pro-MMP-2 (72 kDa) to be activated, resulting the 62 kDa active MMP-2. In this study, we investigated the effect of fibronectin on activation of pro-MMP-2 and the cellular invasiveness in H-Ras-transformed MCF10A human breast epithelial cells. Here we show that fibronectin induces activation of pro-MMP-2 and up-regulation of MT1-MMP and TIMP-2 in H-Ras MCF10A cells. These results demonstrate that H-Ras MCF10A cells secrete high levels of active MMP-2 when cultured with fibronectin, suggesting a possible interaction between the ECM network and H-Ras MCF10A cells to generate active MMP-2 which is important for proteolysis and ECM remodeling. Invasive and migratory abilities of H-Ras MCF10A cells were enhanced by fibronectin. Fibronectin up-regulated the expression of ${\beta}1$ integrin which may play a role in cellular responses exerted by fibronectin. Since acquisition of pro-MMP-2 activation can be associated with increased malignant progression, this study provides a mechanism for the cell surface-matrix degrading effect of fibronectin which will be crucial to breast cell invasion and migration.

• Journal of the Korean Society of Food Culture
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• v.23 no.5
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• pp.629-638
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• 2008

The principal objective of this study was to determine the quality characteristics of seasoned sauce and seasoned pork rib to which pine needle powder was added during storage. The pH value, color value, active bacterial cell count, lipid oxidation, shear force, and sensory evaluation of seasoned sauce and seasoned pork rib to which 0, 1, 2, 3 and 4% pine needle powder was added were measured during storage at $5^{\circ}C$. The storage periods for the seasoned sauce were 0, 1, 3, 5, 7, 14, 21 and 30 days, and the storage periods for the seasoned pork ribs were 0, 1, 3, 5, 7 days. We determined that the pH values of both seasoned sauce and seasoned pork rib decreased with increasing quantities of pine needle powder and longer storage periods. The lightness (L) and yellowness (b) of the seasoned sauce were increased and the redness (a) of that decreased with increasing pine needle powder contents and longer storage periods. The L, a, and b values of the seasoned pork rib decreased with increasing pine needle powder contents, whereas the L and b values of that were decreased and the a value increased with longer storage periods. The active bacterial cell count of the seasoned sauce was detected at between $10^2$ to $10^4$ CFU/mL over a storage period of 30 days, regardless of the addition of pine needle powder; additionally, the addition of 4% pine needle powder resulted in the lowest active bacterial cell count among the samples. The active bacterial cell count in the seasoned pork rib decreased with increasing additions of pine needle powder, and was increased during storage. The influence of pine needle powder contents on the active bacterial cell count of seasoned pork rib were minimal, and the active bacterial cell count of that was suppressed by the addition of only 1% pine needle powder. Lipid oxidation in the seasoned pork rib was suppressed by the addition of more than 2% pine needle powder. We noted no difference in the shear force of the seasoned pork rib to which pine needle powder was added. In our sensory evaluation, the intensity of color (greenish brown), flavor (herbal flavor) and taste (bitter & herbal taste) of the seasoned pork rib increased with increasing pine needle powder contents, whereas the texture of the seasoned pork rib evidenced no differences. The overall acceptability of the seasoned pork rib with 0, 1 and 2% added pine needle powder was higher than that of the seasoned pork rib with 3 and 4% added pine needle powder. Thus, the addition of 2% pine needle powder to seasoned pork rib sauce yielded appropriate results with regard to antibacterial, antioxidative, and sensory properties.

• Korean Journal of Microbiology
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• v.37 no.1
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• pp.80-84
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• 2001

Vertical and temporal variations of active and total bacterial abundance were monthly estimated in Lake Soyang from April 1999 to January 2000. The number of total and respiring bacteria was determined directly under microscope by AODC and CTC methods, respectively. The number of total and active bacteria varied from $2.1{\times}10^5 to 3.1{\times}10^6 $,$cells{\cdot}ml^{-1}$ and $1.8{\times}10^4 to 8.0{\times}10^5 $,$cells{\cdot}ml^{-1}$, respectively. The proportions of respiring bacteria to total cell ranged from 3.7 to 44.2% : The proportions was the highest in November 1999 and the lowest in December 2000. The specific activity of${\beta}$-glucosidase divided by total bacteria was$1.6{\times}10^5\;amol{\cdot}cell^{-1}{\cdot}hr^{-1}$in August and$1.4{\times}10^5\;amol{\times}cell^{-1}{\times}hr^{-1}$in September while the specific activity divided by CTC active bacteria was about$3.6{\times}10^5\;amol{\cdot}cell^{-1}{\cdot}hr^{-1},\;24.0{\times}10^5\;amol{cdot}cell^{-1}{cdot}hr^{-1}$. The specific activity of active bacteria in September was 6.7 times higher than that of August. By these data of active bacteria, the new information of aquatic ecosystem was unveiled.

• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.72-74
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• 2005

In this paper, we propose an adaptive PID controller using a cell-mediated immune response to improve a PID control performance. The proposed controller is based on the specific immune response of the biological immune system that is cell-mediated immunity. The immune system of organisms in the real body regulates the antibody and the T-cells to protect an attack from the foreign materials like virus, germ cells, and other antigens. It has similar characteristics that are the adaptation and robustness to overcome disturbances and to control the plant of engineering application. We first build a model of the T-cell regulated immune response mechanism and then designed an I-PID controller focusing on the T-cell regulated immune response of the biological immune system. We apply the proposed methodology to building structures to mitigate vibrations due to strong winds for evaluation of control performances. Through computer simulations, system responses are illustrated and additionally compared to traditional control approaches.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.74-74
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• 2011

Polymer solar cells utilize bulk heterojunction (BHJ) type photo-active layer in which the electron donating polymer and electron accepting C60 derivatives are mixed together. In the BHJ system the electron donating polymer and electron accepting C60 derivatives are blended. The blended system causes charge recombination at the interface between the BHJ active layer and electrode. To reduce the charge recombination at the interface, it is needed to use an interlayer that can selectively transfer electrons or holes. We have developed solution processable wide band gap inorganic interfacial layers for polymer solar cells. The effect of interlayers on the performance of polymer solar cell was investigated for various types of conjugated polymers. We have found that inorganic interfacial layers enhanced the solar cell efficiency through the reduction of charge recombination at the interface between active layer and electrode. Furthermore, the stability of the polymer solar cell using the interlayer was significantly improved. The efficiency of 6.5% was obtained from the PTB7:PCBM70 based solar cells utilizing $TiO_2$nanoparticles as an interlayers.

• Journal of the Korean Electrochemical Society
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• v.10 no.2
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• pp.104-109
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• 2007

Single fuel cell was fabricated with a MEA (membrane electrode assembly) that had a $4cm^2$ active area and with silicon bipolar plates those were introduced to miniaturize the fuel cell by replacing heavy weight graphite plates. Optimum humidification condition for the single cell was selected based on performance results obtained varying humidifier temperature at a fixed feed rate of hydrogen and oxygen. Furthermore, to study the effect of humidification condition on the performance of a fuel cell stack, the fuel cell stack consisting of two MEAs and silicon bipolar plates was studied, then problems and characteristics of silicon-based fuel cell stack were examined.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1058-1062
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• 1993

A fuzzy reasoning method is proposed for the implementation of control systems based on non-fuzzy microprocessors. The essence of the proposed method is to search the local active miles instead of the global rule base. Thus the reasoning is conveniently performed on a master cell as a fuzzy accelerating kernel, which is transformed from an active fuzzy cell. The interpolative reasoning is simplified via adopting the algebraic product of fulfillment for the conditional connective AND and the weighted average for the rule sentence connective ALSO.

• Korean Journal of Pharmacognosy
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• v.35 no.1 s.136
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• pp.62-79
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• 2004

Cell-scattering is a phenotypic change easily observed in most epithelial cells treated with Hepatocyte Growth Factor /scatter Factor (HGF/SF) or phorbol esters (PKC-activators). Recent studies have shown the possibilities to use as therapeutic materials of HGF/SF or non tumor promoting phorbol esters for liver disease, cancer and AIDS. In this study, we tested a cell-scattering activity of 534 methanol extracts from plants inhabiting in Korean peninsula using the phenotype-based assay system. Nine Active extracts were detected : Daphne genkwa, Daphne kiusiana, and Aleurites fordii showed high activity (+++), Euphorbia sieboldiana and Rhodotypos scandens showed medium activity (++), Sambucus sieboldiana var. pendula, Catalpa bignonioides, Sambucus sieboldiana and Lycoris squamigera showed low activity (+). Furthermore, the effects of these active materials in the culture cells were investigated with biochemical studies.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.11
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• pp.1672-1684
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• 2004

In this paper, an active vibration control with the use of an air-cell seat for passenger cars is investigated. The roles of the air-cell inserted between the polyurethane foam of the seat and seat cover are first to extend the seat's capability to adopt various shapes of human body and to improve the ride-comfort against road disturbances. The air-cell seat is modeled as a 1-d.o.f. spring-damper system. Because an exact modeling of the air-cell itself is alomost impossible, its dynamic characteristics are analyzed through experiments. A road-adaptive gain-scheduled sky-hook control for the air-cell seat system is proposed. The skyhook gains are scheduled in such a way that the acceleration level transmitted to human body on various road conditions is minimized. Simulations and experimental results are provided.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.474-477
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• 2001

The properties of LiMnO$_2$ was studied as a cathode active material for lithium polymer batteries. LiMnO$_2$ cathode active materials were synthesized by the reaction of LiOH . $H_2O$ and Mn$_2$O$_3$at various temperature under argon atmosphere. For lithium polymer battery applications, the LiMnO$_2$cell was characterized electrochemically by charge-discharge experiments and a.c. impedance spectroscopy. And the relationship between the characteristics of powders and electrochemical properties was studied in this research. A maximum discharge capacity of 160-170 mAh/g for ο-LiMnO$_2$ cell was achieved. Used that SP270 as electric active material in LiMnO$_2$, it is excellent than property of electric active material used Acetylene black or KS6 at charge/discharge capacity.