• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.182-185
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• 2003

Lithium ion battery is required to balance cells in order to minimize the electric capacity difference between the batteries. This paper proposes a cell balancing method by using inductor. Simulation and experimental results are presented.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
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• pp.179-179
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• 1993

1. PS및 CP의 flux는 전류의 새기 및 donor의 약물농도에 비래하였다. 2. pH의 flux는 pH가 증가할수록 증가하였으나, CP(pKa=9.2)의 flux는 pH=2에서 최대치를 보였다. 이는 약물의 해리 정도와 H$^{＋}$이온의 mobility, 또 피부의 permselectivity의 balance에 의해 결정된 것으로 생각된다. 3. donor cell에 NaCl을 첨가하면 두 약물 공히, 그러나 특히 PS의 flux가 저하되었다. 이는 두 약물의 이온과 $Na^{＋}$의 mobility차이에 기인한다고 생각된다. 4. PS의 경우 taurodeoxycholate(TDC)같은 음이온을 donor cell에 공존시키면 flux가 감소하였다. 이는 PS와 TDC가 전기적으로 중성인 ion-pair complex를 형성함으로써 PS이온의 유효농도가 감소하기 때문으로 생각된다.

• Molecules and Cells
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• 제24권1호
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• pp.1-8
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• 2007

Natural killer (NK) cells play a crucial role in innate immune system and tumor surveillance. NK cells are derived from $CD34^+$hematopoietic stem cells and undergo differentiation via precursor NK cells in bone marrow (BM) through sequential acquisition of functional surface receptors. During differentiation of NK cells, many factors are involved including cytokines, membrane factors and transcription factors as well as microenvironment of BM. NK cells express their own repertoire of receptors including activating and inhibitory receptors that bind to major histocompatibility complex (MHC) class I or class I-related molecules. The balance between activating and inhibitory receptors determines the function of NK cells to kill targets. Binding of NK cell inhibitory receptors to their MHC class I-ligand renders the target cells to be protected from NK cell-mediated cytotoxicity. Thus, NK cells are able to discriminate self from non-self through MHC class I-binding inhibitory receptor. Using intrinsic properties of NK cells, NK cells are emerging to apply as therapeutic agents against many types of cancers. Recently, NK cell alloactivity has also been exploited in killer cell immunoglobulin-like receptor mismatched haploidentical stem cell transplantation to reduce the rate of relapse and graft versus host disease. In this review, we discuss the basic mechanisms of NK cell differentiation, diversity of NK cell receptors, and clinical applications of NK cells for anti-cancer immunotherapy.

• BMB Reports
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• 제53권8호
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• pp.400-412
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• 2020

The world has witnessed unimaginable damage from the coronavirus disease-19 (COVID-19) pandemic. Because the pandemic is growing rapidly, it is important to consider diverse treatment options to effectively treat people worldwide. Since the immune system is at the hub of the infection, it is essential to regulate the dynamic balance in order to prevent the overexaggerated immune responses that subsequently result in multiorgan damage. The use of stem cells as treatment options has gained tremendous momentum in the past decade. The revolutionary measures in science have brought to the world mesenchymal stem cells (MSCs) and MSC-derived exosomes (MSC-Exo) as therapeutic opportunities for various diseases. The MSCs and MSC-Exos have immunomodulatory functions; they can be used as therapy to strike a balance in the immune cells of patients with COVID-19. In this review, we discuss the basics of the cytokine storm in COVID-19, MSCs, and MSC-derived exosomes and the potential and stem-cell-based ongoing clinical trials for COVID-19.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.636-639
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• 2009

Fuel consumption measurement of Hydrogen fuel cell vehicle is considerably different form internal combustion engine vehicle such as carbon balance method. A practical method of fuel Consumption measurement has been developed for Hydrogen fuel cell vehicles. There are three method of hydrogen fuel consumption testing, gravimetric, PVT(Pressure, Volume and temperature), and Coriolis mass flow, all of which necessitate physical measurements of the fuel supply. The purpose of this research is to measure the fuel consumption of hydrogen fuel cell vehicles on chassis-dynamometer and to give information when the research is intended to develop method to measure hydrogen fuel consumption.

• 한국수소및신에너지학회논문집
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• 제18권1호
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• pp.60-66
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• 2007

In terms of the vehicle efficiency, a fuel cell hybrid system has advantages compared to a conventional internal combustion engine and a fuel cell alone-powered system. The efficiency of the fuel cell hybrid vehicle mainly depends on the maximum power of the fuel cell and therefore it is important to decide the design value of the fuel cell maximum power. In this paper, to estimate the performance of the fuel cell hybrid mini-bus in the design phase the simulator based on the models for the fuel cell stack, the electric battery, the fuel cell balance of plant, the controller, and the vehicle itself is proposed. Additionally, the hybrid mini-bus efficiencies with several different fuel cell powers are simulated for a city driving schedule and are compared on another. Consequently, the proposed simulation scheme is useful to determine the best design value of the fuel cell hybrid vehicles.

• IMMUNE NETWORK
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• 제12권6호
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• pp.240-246
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• 2012

Natural killer (NK) cells play a pivotal role in early surveillance against virus infection and cellular transformation, and are also implicated in the control of inflammatory response through their effector functions of direct lysis of target cells and cytokine secretion. NK cell activation toward target cell is determined by the net balance of signals transmitted from diverse activating and inhibitory receptors. A distinct feature of NK cell activation is that stimulation of resting NK cells with single activating receptor on its own cannot mount natural cytotoxicity. Instead, specific pairs of co-activation receptors are required to unleash NK cell activation via synergy- dependent mechanism. Because each co-activation receptor uses distinct signaling modules, NK cell synergy relies on the integration of such disparate signals. This explains why the study of the mechanism underlying NK cell synergy is important and necessary. Recent studies revealed that NK cell synergy depends on the integration of complementary signals converged at a critical checkpoint element but not on simple amplification of the individual signaling to overcome intrinsic activation threshold. This review focuses on the signaling events during NK cells activation and recent advances in the study of NK cell synergy.

• 신재생에너지
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• 제1권4호
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• pp.43-48
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• 2005

This study presents the integrated modeling approach to simulate the proton exchange membrane [PEM] fuel cell system for vehicle application. The fuel cell system consisting of stack and balance of plant (BOP) was simulated with MATLAB/Simulink environment to estimate the maximum system power and investigate the effect of BOP component sizing on system performance and efficiency. The PEM fuel cell stack model was established by using a semi-empirical modeling. To maximize the net efficiency of fuel cell system, multi-variable optimization code was adopted. Using this method, the optimized operating values were obtained according to various system net power levels. The fuel cell model established was co-linked to AVL CRUISE, a vehicle simulation package. Through the vehicle simulation software, the fuel economy of fuel cell powered electric vehicle for two types of driving cycles was presented and compared. It is expected that this study can be effectively employed in the basic BOP component sizing and in establishing system operation map with respect to net power level of fuel cell system.

• 한국발생생물학회지:발생과생식
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• 제15권2호
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• pp.143-150
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• 2011

이 연구는 수중 운동, 균형 훈련과 복합 운동이 파킨슨 유발 흰쥐 모델에 미치는 영향을 관찰하기 위해 수산화도파민(6-hydroxydopamine)을 흰쥐의 좌측 내측전뇌다발에 주사하여 파킨슨 모델을 제작하였다. 실험동물은 수중 운동을 적용한 실험군 I, 균형 훈련을 적용한 실험군 II, 복합 운동(수중 운동+균형 훈련)을 적용한 실험군 III, 수술 후 표준사육장에서 운동을 적용하지 않은 대조군으로 배치하였다. 수술 후 7일, 14일, 21일에 실험동물의 중뇌 흑질의 도파민 세포감소를 관찰하기 위하여 TH(tyrosine hydroxylase)의 발현 양상을 관찰하였고, 행동학적 검사로 수술 후 1일, 7일, 14일,21일에 아포몰핀유도 회전 검사를 실시하였다. 실험 결과, 실험군들에서 대조군에 비하여 유의하게 높은 TH 발현과 아포몰핀유도 회전수를 보였다. 하지만 실험군들 사이에는 유의한 차이가 나타나지 않았다. 이상의 결과에서 파킨슨유발 흰쥐모델이 기능 회복에 수중 운동과 균형 훈련이 효과적임을 알 수 있었으며, 흑질 치밀부의 도파민성 신경섬유의 증감을 나타내는 TH의 발현에도 수중 운동과 균형 훈련이 효과적임을 알 수 있었다.

• Journal of Microbiology and Biotechnology
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• 제9권2호
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• pp.140-146
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• 1999

When methanol was the sole carbon source, Methylobacterium organophilum NCIB 11278, a facultative methylotroph, accumulated Poly-$\beta$-hydroxybutyrate (PHB) as 59% (w/w) of dry cell weight under potassium limitation, 37% under sulfate limitation, and 33% under nitrogen limitation. Based on a stoichiometric analysis of PHB synthesis from methanol, it was suspected that PHB synthesis is accompanied by the overproduction of energy, either 6-10 ATP and 1 $FADH_2$ or 6 ATP and 3 NADPH to balance the NADH requirement, per PHB monomer. This was confirmed by observation of increased intracellular ATP levels during PHB accumulation. The intracellular ATP with limited potassium, sulfate, and ammonium increased to 0.185, 0.452, and 0.390 $\mu$moles ATP/g Xr (residual cell mass) during PHB accumulation, respectively. The intracellular ATP level under potassium limitation was similar to that when there was no nutrient limitation and no PHB accumulation, 0.152- 0.186 $\mu$moles ATP/g Xr. We propose that the maximum PHB accumulation observed when potassium was limited is a result of the energy balance during PHB accumulation. Microorganisms have high energy requirements under potassium limitation. Enhanced PHB accumulation, in ammonium and sulfate limited conditions with the addition of 2,4-dinitrophenol, which dissipates surplus energy, proves this assumption. With the addition of 1 mM of 2,4-dinitrophenol, the PHB content increased from 32.4% to 58.5% of dry cell weight when nitrogen limited and from 15.1 % to 31.0% of dry cell weight when sulfate limited.