• Title/Summary/Keyword: the bio current

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Dielectric Relaxation Characteristics of Biology Thin Film (생체박막의 유전완화특성)

  • Song, Jin-Won;Cho, Su-Young;Lee, Kyung-Sup;Sin, Hun-Gyu
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.05c
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    • pp.107-110
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    • 2003
  • In this paper, We introduced that the method for determing the dielectric relaxation time $\tau$ of floating monolayers on water interface. Displacement current flowing across monolayers is analyzed using a rod-like molecular model. It is revealed that the dielectric relaxation time $\tau$of monolayers in the isotropic polar orientational phase is determined using a linear relationship between the monolayer compression speed $\alpha$ and the molecular area Am. here Displacement current gives a peak at A = Am. The dielectric relaxation time $\tau$ of organic monolayers was examined on the basis of the analysis developed here.

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Effect of Electrode Materials and Applied Potential in Electrocatalytic Reduction of Carbon Dioxide by Carbon Monoxide Dehydrogenase (일산화탄소탈수소화효소를 이용한 이산화탄소의 전기화학적 환원에 미치는 전극재료와 전위의 영향)

  • Shin, Jun Won;Kim, You-Sung;Song, Ji-Eun;Lee, Sang-Hee;Lee, Sang-Phil;Lee, Ho-Jun;Lim, Mi-Ran;Shin, Woon-Sup
    • Journal of the Korean Electrochemical Society
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    • v.11 no.3
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    • pp.165-169
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    • 2008
  • The effect of reduction of carbon dioxide by CODH(Carbon Monoxide Dehydrogenase) was compared on glassy carbon and gold working electrodes. In case of gold electrode, the choice of the optimum applied potential is very important since $H_2$ evolution can be mixed with $CO_2$ reduction. On the other hand, efficient $CO_2$ reduction was observed up to -650 mV vs. NHE on glassy carbon in neutral solution due to the larger overpotential for $H_2$ evolution on glassy carbon surface than that on gold surface. The optimum potential for $CO_2$ reduction was found to be $-570{\sim}600\;mV$ vs. NHE. The current efficiency of $CO_2$ to CO decreased dramatically at more negative potential according to the activity of enzyme decrease and the hydrogen evolution.

A Study of Magnetic Field Characteristic of Field coil in HTS motor (HTS 전동기용 계자코일의 자장 특성 연구)

  • 이정종;조영식;홍정표;손명환;김석환;권영길
    • Progress in Superconductivity and Cryogenics
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    • v.4 no.2
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    • pp.47-51
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    • 2002
  • In this paper, flux distribution and operating current is calculated according to the field coil change in HTS(High Temperature Superconducting) motor. In order to calculate magnetic field characteristic of the field coil. it is computed by changing the outer radius and the inner width of field coil Bio-Savart equation is used as the analysis method for the characteristic analysis of magnet. 2D and 3D FEA(Finite Element Analysis) is used for the magnetic field distribution in HTS motor The operating current is calculated by $B{\bot}$ linked With the field coil and $I_c-B curve of superconductor.

Inhibitory Effects of Quercetin on Muscle-type of Nicotinic Acetylcholine Receptor-Mediated Ion Currents Expressed in Xenopus Oocytes

  • Lee, Byung-Hwan;Shin, Tae-Joon;Hwang, Sung-Hee;Choi, Sun-Hye;Kang, Ji-Yeon;Kim, Hyeon-Joong;Park, Chan-Woo;Lee, Soo-Han;Nah, Seung-Yeol
    • The Korean Journal of Physiology and Pharmacology
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    • v.15 no.4
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    • pp.195-201
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    • 2011
  • The flavonoid quercetin is a low molecular weight compound generally found in apple, gingko, tomato, onion and other red-colored fruits and vegetables. Like other flavonoids, quercetin has diverse pharmacological actions. However, relatively little is known about the influence of quercetin effects in the regulation of ligand-gated ion channels. Previously, we reported that quercetin regulates subsets of nicotinic acetylcholine receptors such as ${\alpha}3{\beta}4$, ${\alpha}7$ and ${\alpha}9{\alpha}10$. Presently, we investigated the effects of quercetin on muscle-type of nicotinic acetylcholine receptor channel activity expressed in Xenopus oocytes after injection of cRNA encoding human fetal or adult muscle-type of nicotinic acetylcholine receptor subunits. Acetylcholine treatment elicited an inward peak current ($I_{ACh}$) in oocytes expressing both muscle-type of nicotinic acetylcholine receptors and co-treatment of quercetin with acetylcholine inhibited $I_{ACh}$. Pre-treatment of quercetin further inhibited $I_{ACh}$ in oocytes expressing adult and fetal muscle-type nicotinic acetylcholine receptors. The inhibition of $I_{ACh}$ by quercetin was reversible and concentration-dependent. The $IC_{50}$ of quercetin was $18.9{\pm}1.2{\mu}M$ in oocytes expressing adult muscle-type nicotinic acetylcholine receptor. The inhibition of $I_{ACh}$ by quercetin was voltage-independent and non-competitive. These results indicate that quercetin might regulate human muscle-type nicotinic acetylcholine receptor channel activity and that quercetin-mediated regulation of muscle-type nicotinic acetylcholine receptor might be coupled to regulation of neuromuscular junction activity.

The Development of Expression Process Leading to Ethanol Production with Highly Active Cellulase Modified by Directed Evolution (목질계 Cellulose로부터의 Ethanol의 경제적인 생산공정을 위하여 분자진화에 의한 활성이 획기적으로 증가된 Cellulase의 대량 발현공정 개발)

  • Kang, Whan-Koo;Jeung, Jong-Sik;Kim, Hyang-Sik;Kim, Bum-Change;Yun, Ji-Sun;Park, Hyang-Su
    • KSBB Journal
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    • v.22 no.1
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    • pp.16-21
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    • 2007
  • Although Energy demands of modern society increase rapidly, current energy would be exhausted shortly. Therefore development of bio-ethanol production process from cellulose containing materials was extremly demanded. Therefore development of highly functional cellulase is requisite for this purpose. In this study cellobio-hydrolase (CBH1) gene from Trichorderma reesei was used to increase cellulase activity by directed evolution and highly functional cellobio-hydrolase was obtained and characterized.

A study of the relations between meridian and the disease (병증(病症)의 경락비교(經絡比較)에 관(關)한 연구(硏究))

  • Shin, Yong-Cheol;An, Sang-Woo
    • Korean Journal of Oriental Medicine
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    • v.1 no.1
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    • pp.245-272
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    • 1995
  • The meridians are energy pathways found in the interior organs of the body leading the bio-electrical energy the periphery of the body for its energetic supply and the meridians connect the individual acupuncture points. The acupucture points in turn serve for the interference with the bio-electric energy, thus made it measurable. It has been developed to a stage where one could stimulate the acupuncture-points in order to achieve organ effects in the body. To the contrast, Dr.Niboyet proved that the human skin contains points varing in their electrical roperties as to their surroundings. He also tried to send direct current through the skin taken from the body and derive it at other places of the skin characterized by the above mentioned meridians and acupuncture points. The body produces a potential in the organs to reach the acupuncture point via the meridians. The charge on the individual acupuncture point caused by the exactly difinable current of our mesurement device, creates a state of blance between the irritational potential, both of whcih are which are opposite to each other. The body processes the irritational current in the acupuncture point. Voll and Werner, as early as 1953, developed an instruments for applying electro-acupuncture on the skin without needle picks and the teaching from part of modern medicine after developing over recent years. Electro-acupucture is a comprechensive fterm for all procedures based on mesurements or thrapy derived from Oriental acupuncture, using modern electronics. As a result, I found the phenomena of the meridian during the disease. And It seems to be closely related between the meriduan and the disease. I think it must be researched profoundly and for the long time.

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Exploration of the Binding Mode of Indole Derivatives as Potent HIV-1 Inhibitors Using Molecular Docking Simulations

  • Balupuri, Anand;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.6 no.3
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    • pp.138-142
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    • 2013
  • The HIV-1 envelope glycoprotein gp120 plays a vital role in the entry of the virus into the host cells. The crucial role of the glycoprotein suggests gp120 as potential drug target for the future antiviral therapies. Identification of the binding mode of small drug like compounds has been an important goal in drug design. In the current study we attempt to propose binding mode of indole derivatives in the binding pocket of gp120. These derivatives are reported to inhibit HIV-1 by acting as attachment inhibitors that bind to gp120 and prevent the gp120-CD4 interaction and thus inhibit the infectivity of HIV-1. To elucidate the molecular basis of the small molecules interactions to inhibit the glycoprotein function we employed the molecular docking simulation approach. This study provides insights to elucidate the binding pattern of indole-based gp120 inhibitors and may help in the rational design of novel HIV-1 inhibitors with improved potency.

Development of a Supporting System for Nutrient Solution Management in Hydroponics - II. Estimation of Electrical Conductivity(EC) using Neural Networks (양액재배를 위한 배양액관리 지원시스템의 개발 - II. 신경회로망에 의한 전기전도도(EC)의 추정)

  • 손정익;김문기;남상운
    • Journal of Bio-Environment Control
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    • v.1 no.2
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    • pp.162-168
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    • 1992
  • As the automation of nutrient solution management proceeds in the field of hydroponics, effective supporting systems to manage the nutrient solution by computer become needed. This study was attempt to predict the EC of nutrient solution using the neural networks. The multilayer perceptron consisting of 3 layers with the back propagation learning algorithm was selected for EC prediction, of which nine variables in the input layer were the concentrations of each ion and one variable in the output layer the EC of nutrient solution. The meq unit in ion concentration was selected fir input variable in the input layer. After the 10,000 learning sweeps with 108 sample data, the comparison of predicted and measured ECs for 72 test data showed good agreements with the correlation coefficient of 0.998. In addition, the predicted ECs by neural network showed relatively equal or closer to the measured ones than those by current complicated models.

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Understanding of the Hepatitis B virus via System Dynamics Model (만성 B형간염환자의 재발 방지 및 삶의 질 향상을 위한 시스템 다이내믹스 모델 개발)

  • Paik, Seung-Woon;Choi, Eun-Ok;Kim, Keum-Soon;Yi, Myung-Sun;Kwak, Sang-Man
    • Korean System Dynamics Review
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    • v.7 no.2
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    • pp.215-226
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    • 2006
  • A conceptual system dynamics model is developed to represent the dynamic mechanism between the number of hepatitis B virus and the defense system of the body. The simulation results shows that the model behaves within the reasonable ranges. The developed conceptual model is a first attempt to quantify the dynamic mechanisms of the hepatitis B virus, where only feedback structures are considered without bio-organism data. The next step would be to incorporate the model with bio-organism theory and to carry out case studies to identify personal characteristics. Since the current model is a conceptual model where quantitative results are not based on the sound background, the usage is limited only within the qualitative basis. It could be a effective educational tool for the patients. It also shows what-to-do lists in order to be used for forecast purposes.

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Study on the Atmospheric Plasma Characteristics of Dielectric Barrier Discharge due to a Variation of the Duty Ratio of Pulse Modulation (펄스변조의 듀티비 변경에 따른 DBD 대기압 플라즈마 특성 연구)

  • Park, Jong-in;Hwang, Sang-hyuk;Jo, Tae Hoon;Yun, Myoung Soo;Kwak, Hyoung sin;Jin, Gi nam;Jeon, Buil;Choi, Eun Ha;Kwon, Gi-Chung
    • Korean Journal of Materials Research
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    • v.25 no.11
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    • pp.616-621
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    • 2015
  • Atmospheric pressure plasma is used in the biological and medical fields. Miniaturization and safety are important in the application of apply atmospheric plasma to bio devices. In this study, we made a small, pocket-sized inverter for the discharge of atmospheric plasma. We used pulse power to control the neutral gas temperature at which the, when plasma was discharged. We used direct current of 5 V of bias(voltage). The output voltage is about 1 to 2 kilo volts the frequency is about 80 kilo hertz. We analyzsed the characteristics of the atmospheric plasma using OES(Optical emission spectroscopy) and the Current-Voltage characteristic of pulse power. By calculating of the current voltage characteristics, we were able to determine that, when the duty ratio increased, the power that actually effects the plasma discharge also increased. To apply atmospheric plasma to human organisms, the temperature is the most important factor, we were able to control the temperature by modulating the pulse power duty ratio. This means we can use atmospheric plasma on the human body or in other areas of the medical field.