• Title/Summary/Keyword: Potential rise

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Influences of Gastric Mucosa upon the Catecholamine Induced Gastric Motility in Guinea-pig (기니피그 위점막이 카테콜아민 유발 위운동에 미치는 영향)

  • Rhee, Poong-Lyul;Kim, Ki-Whan;Lee, Sang-Jin
    • The Korean Journal of Physiology
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    • v.23 no.2
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    • pp.277-289
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    • 1989
  • The effects of noradrenaline on the contractile and electrical activities were investigated using the circular muscle strips with intact mucosa prepared from the antrum and fundus of guinea-pig stomach. Electrical responses of circular muscle cells were recorded using glass capillary microelectrodes filled with 3 M KCI. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% $O_2\;and\;kept\;at\;35^{\circ}C$. The results obtained were as follows: 1) The spontaneous contractions recorded from the antral and fundic circular muscle strips with intact mucosa were suppressed dose-dependently by the application of noradrenaline, whereas those recorded from the mucosa-free strips were potentiated in a dose-dependent manner. 2) The inhibitory influences on the contractile activities in the normal intact strips were developed via both ${\alpha}-adrenoceptors\;and\;{\beta}-adrenoceptors$, while the excitatory influences in the mucosa-free strips resulted from the strong excitatory effect via ${\alpha}-adrenoceptors$ and the weak inhibitory effect via ${\beta}-adrenoceptors$. 3) Noradrenaline produced hyperpolarization of membrane potential, and increased the amplitude and the maximum rate of rise of slow waves in the mucosa-free strips of antral and fundic circular muscle. 4) Apamin blocked the appearance of the component of initial suppression of spontaneous phasic contractions observed in the mucosa-free strips of antral circular muscle after the application of noradrenaline. 5) The inhibitory influences on the contractile activities in the normal strips with intact mucosa remained unaffected even in the strip with separate mucosa, in which mucosa and muscle layer were mechanically disconnected . From the above results, following conclusions could be made. (1) There are no regional differences between the effects of noradrenaline on the antral circular muscle and those on the fundic circular muscle. (2) Excitatory responses to noradrenaline observed in the mucosa-free strip result from the dominant ${\alpha}-excitatory$ and tile weak ${\beta}-inhibitory$ action of noradrenaline. (3) Inhibitory responses to noradrenaline in the normal strips with intact mucosa develop via both ${\alpha}-inhibitory\;and\;{\beta}-inhibitory$ actions.

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Measurement of CYP450 Enzymes Activity of Bosentan in HepaRG Cell (HepaRG 세포를 이용한 Bosentan 약물의 CYP450 효소활성 측정)

  • Han, Kyoung-Moon;Jung, Jung-A;Sin, Ji-Soon;Cha, Hye-Jin;Bae, Young-Ji;Kim, Hyun-Uk;Kim, Young-Hoon;Seong, Won-Keun;Kang, Hoil
    • YAKHAK HOEJI
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    • v.58 no.4
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    • pp.255-261
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    • 2014
  • Poly-pharmacy has been on the rise because of aging of population and chronic disease. Most of drug metabolism happens in the liver by CYP isozymes and the metabolism by CYP450 enzymes. The Cytochrome P450 (CYP) is a superfamily of enzymes that catalyzes the oxidations of many endogenous and exogenous compounds. Primary human Hepatocytes (HH) are considered as the gold standard model for In vitro drug interaction studies. However, there are several limitations (cost, limited life span) for using HH cells. HepaRG cells are being used as a possible alternative. HepaRG cells were cultured in William E medium containing the positive control inducers (1A2: 10, 25, 50 ${\mu}M$ omeprazole, 2C9 and 2C19: 10 ${\mu}M$ rifampin, 3A4: 10, 25, 50 ${\mu}M$ rifampin) at $37^{\circ}C$, 5 % $CO_2$ in a humidified atmosphere. This study was to evaluate the induction of CYP isozymes (1A2, 2C9, 2C19 and 3A4) using LC-MS/MS. We evaluated the potential induction ability of Bosentan, as a drug of pulmonary artery hypertension, in HepaRG cells. For reference, dose of the Bosentan is determined to the basis of the $C_{max}$ (835 mg/ml) value. The enzyme activity demonstrated that CYP2C9 and 3A4 were induced up to 20 times by Bosentan. Like as In vivo, the enzyme activity of CYP2C9 and CYP3A4 is significantly induced in a dose-dependent by Bosentan.

Studies of Aleolar-Mixed Venous CO2 and O2 Gradients in the Rebreathing Dog Lung (반복호흡(反覆呼吸)을 하는 견폐(犬肺)에서의 폐포(肺胞)와 혼합정맥혈액(混合靜脈血液)의 CO2 및 O2 경사도(傾斜度)에 대한 연구(硏究))

  • Yu, Chang Jun
    • Korean Journal of Veterinary Research
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    • v.12 no.1
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    • pp.37-50
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    • 1972
  • Another comparison of alveolar gas pressures, in a continuously rebreathing dog lung, with pulmonary arterial (mixed venous) blood, again showed alveolar pressures to be the higher for $CO_2$ and usually $O_2$ (positive ${\Delta}Pco_2$, and ${\Delta}Po_2$). ${\Delta}Pco_2$ was almost invariably positive, it was independant of time and of plasma pH changes produced by acid or bicarbonate infusion, but proportional to blood $CO_2$ level. It was seemingly little affected by the distribution or magnitude of blood flow nor did it result from failure of $CO_2$ equilibrium within the blood, but it did rise with carbonic anhydrase inhibition. ${\Delta}Po_2$ was more variable and sometimes negative, particularly at low blood flow rates. It seemed in dependant of time, and plasma pH changes, apart from an inverse relationship with that resulting from $CO_2$ changes. It existed despite considerable potential for gas exchange, and was unaffected by inhibition of the $CO_2$ reactions.

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Estimation of Maximum Typhoon Intensity Considering Climate Change Scenarios and Simulation of Corresponding Storm Surge (기후변화 시나리오에 따른 최대 가능 태풍강도 추정 및 이에 따른 폭풍해일고 양상 모의)

  • Yoon, Jong-Joo;Jun, Ki-Cheon;Shim, Jae-Seol;Park, Kwang-Soon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.4
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    • pp.292-301
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    • 2012
  • The rise in sea surface temperature (SST) as a global warming enhance overall typhoon activity. We assumed that there exist thermodynamic limits to intensity that apply in the absence of significant interaction between storms and their environment. The limit calculations depend on SST and atmospheric profiles of temperature and moisture. This approach do appear to provide resonable upper bounds on the intensities of observed storms and may even be useful for predicting the change in intensity over a long period time. The maximum storm intensities was estimated through the global warming scenarios from IPCC-AR4 report over the North-East Asia. The result shows stronger intensities according to scenarios for increase of carbon dioxide levels. And storm surge simulations was performed with the typhoons which were combined route of the typhoon Maemi (2003) and intensity as climate change scenarios. The maximum increase of storm surge heights was shown about 29~110 cm (36~65%) regionally. Especially at Masan, the result of simulated maximum surge height exceed the 200 years return period surge.

Analysis of Trace Copper Metal at The Electrode Consisting of Carbon Nanotube using Stripping Voltammetry (벗김전압전류법을 이용한 카본나노튜브 전극에서의 구리 분석)

  • Choi, Chang-Kun;Jung, Young-Sam;Kim, Nack-Joo;Pak, Dae-Won;Chung, Kun-Yong;Kim, Lae-Hyun;Kwon, Yong-Chai
    • Korean Chemical Engineering Research
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    • v.50 no.5
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    • pp.933-937
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    • 2012
  • In the present study, we evaluate the sensitivity and optimal stripping voltammetry (SV) conditions of copper (Cu), which is one of the main trace heavy metals inducing the environmental contamination, using carbon nanotube (CNT) electrode. In addition, the reaction mechanism of stripping reaction of Cu is investigated. The electrochemical analyses such as squarewave stripping voltammetry (SWSV) and linear scan voltammetry (LSV) are used for the evaluations. As a result of that, the best SWSV conditions like squarewave amplitude of 15 mV, frequency of 60 Hz, deposition potential of -1.0V vs. Ag/AgCl and deposition time of 200s are determined with the measured Cu sensitivity of $1.824{\mu}A/{\mu}M$. As a driving force affecting the stripping reaction of Cu, surface reaction is more dominant one than diffusion. These results are compared with other reference results and it is confirmed that our suggested CNT electrode gives rise to better Cu sensitivity result than other references.

Model Proposal for Detection Method of Cyber Attack using SIEM (SIEM을 이용한 침해사고 탐지방법 모델 제안)

  • Um, Jin-Guk;Kwon, Hun-Yeong
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.16 no.6
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    • pp.43-54
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    • 2016
  • The occurrence of cyber crime is on the rise every year, and the security control center, which should play a crucial role in monitoring and early response against the cyber attacks targeting various information systems, its importance has increased accordingly. Every endeavors to prevent cyber attacks is being attempted by information security personnel of government and financial sector's security control center, threat response Center, cyber terror response center, Cert Team, SOC(Security Operator Center) and else. The ordinary method to monitor cyber attacks consists of utilizing the security system or the network security device. It is anticipated, however, to be insufficient since this is simply one dimensional way of monitoring them based on signatures. There has been considerable improvement of the security control system and researchers also have conducted a number of studies on monitoring methods to prevent threats to security. In accordance with the environment changes from ESM to SIEM, the security control system is able to be provided with more input data as well as generate the correlation analysis which integrates the processed data, by extraction and parsing, into the potential scenarios of attack or threat. This article shows case studies how to detect the threat to security in effective ways, from the initial phase of the security control system to current SIEM circumstances. Furthermore, scenarios based security control systems rather than simple monitoring is introduced, and finally methods of producing the correlation analysis and its verification methods are presented. It is expected that this result contributes to the development of cyber attack monitoring system in other security centers.

An analysis on the Investment Determinants for Urban Business Hotel Development (도심 비즈니스호텔 개발사업의 투자결정요인에 관한 연구)

  • Ha, Jung-huhn;Jeong, Moonoh;Lee, Sangyoub
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.4
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    • pp.107-117
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    • 2015
  • As the demand for urban business hotel has increased in the recent years due to the sharp rise in overseas tourists, the potential of business hotel development has gained in financial attention for the real estate investment. However, its concept and business domain has not been defined, and none of investment guidance for the development has not been clarified. Accordingly, this report intends to define the concept of urban business hotel in perspective of real estate investment through prior case studies and literature review, and provide the structure of determinants which control its investment decisions. Furthermore, this study develops the weight of determinants depending on the type of investment, and evaluate the two actual projects in urban area of Seoul, differed from investment type: direct and indirect, based on AHP and Fuzzy methodologies. Research finding indicate that the financial factors affecting the sales and tour business condition factors are critical determinants regardless of investment type. And it is notable that the direct investment perspective pays more attention on the finance and investment associated determinants while the indirect one more focuses on the regional and environmental ones. From the analysis of case evaluation, it is also noteworthy that the direct investors turn out to be more conservative than indirect investors due to the risk of equity capital investment.

A Study on the Safety Characterization Grounding Design of the Inner Photovoltaic System (태양광 발전단지 내부 그리드의 안전 특성화 접지 설계에 관한 연구)

  • Kim, Hong-Yong;Yoon, Suk-Ho
    • Journal of the Society of Disaster Information
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    • v.14 no.2
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    • pp.130-140
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    • 2018
  • Purpose: In this paper, we propose a design technique for the safety characterization grounding in the construction of the photovoltaic power generation complex which can be useful and useful as an alternative power energy source in our society. In other words, we will introduce the application of safety grounding for each application, which can improve and optimize the reliability of the internal grid from the cell module to the electric room in the photovoltaic power generation complex. Method: We analyze the earth resistivity of the soil in the solar power plant and use the computer program (CDEGS) to analyze the contact voltage and stratospheric voltage causing the electric shock, and propose the calculation and calculation method of the safety ground. In addition, we will discuss the importance of semi-permanent ground electrode selection in consideration of soil environment. Results: We could obtain the maximum and minimum value of ground resistivity for each of the three areas of the data measured by the Wenner 4 - electrode method. The measured data was substituted into the basic equation and calculated with a MATLAB computer program. That is, it can be determined that the thickness of the minimum resistance value is the most favorable soil environment for installing the ground electrode. Conclusion: Through this study, we propose a grounding system design method that can suppress the potential rise on the ground surface in the inner grid of solar power plant according to each case. However, the development of smart devices capable of accumulating big data and a monitoring system capable of real-time monitoring of seismic changes in earth resistances and grounding systems should be further studied.

Evaluation of CO2 Balance in the Barley-Red Pepper and Barley-Soybean Cropping System (보리-고추와 보리-콩 작부체계에서 이산화탄소수지 평가)

  • Kim, Gun-Yeob;Suh, Sang-Uk;Ko, Byung-Gu;Jeong, Hyun-Cheol;Roh, Kee-An;Shim, Kyo-Moon
    • Korean Journal of Soil Science and Fertilizer
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    • v.41 no.6
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    • pp.408-414
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    • 2008
  • Importance of climate change and its impact on agriculture and environment has increased with the rise Green House Gases (GHGs) concentration in the atmosphere. To slow down the speed of climate change many efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In agricultural sector, many researches have been performed on GHGs emission reduction, but few on the role of carbon sink. In this study, we investigated carbon balance and soil carbon storage in agricultural field in the barley-red pepper and barley-soybean cropping system. With the system for automatic measuring of carbon dioxide, net ecosystem production(NEP) was estimated to be $6.3ton\;CO_2\;ha-1$ for N-P-K chemical fertilizer treatment plot and $10.6ton\;CO_2\;ha^{-1}$ for N-P-K chemical fertilizer with swine manure treatment plot in the barley-soybean rotation cropping. In the barley-red pepper rotation cropping, it was $12.0ton\;CO_2\;ha^{-1}$ for N-P-K chemical fertilizer treatment plot and $13.2ton\;CO_2\;ha^{-1}$ for N-P-K chemical fertilizer with swine manure treatment plot. Soil carbon storage rate was estimated to be $0.7ton\;C\;ha^{-1}$ for the barley-soybean cropping system and $0.5ton\;C\;ha^{-1}$ for barley-pepper cropping system. In appeared that agricultural lands may contribute to the greenhouse effect as a potential carbon sink preserving carbon into soil.

Changes of Cytosolic $Ca^{2+}$ under Metabolic Inhibition in Isolated Rat Ventricular Myocytes

  • Kang, Sung-Hyun;Kim, Na-Ri;Joo, Hyun;Youm, Jae-Boum;Park, Won-Sun;Warda, Mohamed;Kim, Hyung-Kyu;Von Cuong, Dang;Kim, Tae-Ho;Kim, Eui-Yong;Han, Jin
    • The Korean Journal of Physiology and Pharmacology
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    • v.9 no.5
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    • pp.291-298
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    • 2005
  • To characterize cytosolic $Ca^{2+}$ fluctuations under metabolic inhibition, rat ventricular myocytes were exposed to $200{\mu}M$ 2,4-dinitrophenol (DNP), and mitochondrial $Ca^{2+}$, mitochondrial membrane potential (${\Delta}{\Psi}m$), and cytosolic $Ca^{2+}$ were measured, using Rhod-2 AM, TMRE, and Fluo-4 AM fluorescent dyes, respectively, by Laser Scanning Confocal Microscopy (LSCM). Furthermore, the role of sarcolemmal $Na^+$/$Ca^{2+}$ exchange (NCX) in cytosolic $Ca^{2+}$ efflux was studied in KB-R7943 and $Na^+$-free normal Tyrode's solution (143 mM LiCl ). When DNP was applied to cells loaded with Fluo-4 AM, Fluo-4 AM fluorescence intensity initially increased by $70{\pm}10$% within $70{\pm}10$ s, and later by $400{\pm}200$% at $850{\pm}45$ s. Fluorescence intensity of both Rhod-2 AM and TMRE were initially decreased by DNP, coincident with the initial increase of Fluo-4 AM fluorescence intensity. When sarcoplasmic reticulum (SR) $Ca^{2+}$ was depleted by $1{\mu}M thapsigargin plus $10{\mu}M ryanodine, the initial increase of Fluo-4 AM fluorescence intensity was unaffected, however, the subsequent progressive increase was abolished. KB-R7943 delayed both the first and the second phases of cytosolic $Ca^{2+}$ overload, while $Na^+$-free solution accelerated the second. The above results suggest that: 1) the initial rise in cytosolic $Ca^{2+}$ under DNP results from mitochondrial depolarization; 2) the secondary increase is caused by progressive $Ca^{2+}$ release from SR; 3) NCX plays an important role in transient cytosolic $Ca^{2+}$ shifts under metabolic inhibition with DNP.