• BMB Reports
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• v.32 no.4
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• pp.385-392
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• 1999

The $NAD^+$-specific activity of a dual coenzyme-specific isocitrate dehydrogenase (IDH; EC 1.1.1.41) from the primitive fungus Pythium ultimum was investigated to elucidate the regulatory factors that may influence the intracellular distribution of carbon and the availability of intermediates, e.g. citrate, for fatty acid synthesis. Inhibition of $NAD^+$-IDH activity by diphospho- and triphosphonucleotides (ATP, ADP, and GTP) reflected the sensitivity of this enzyme to cellular energy charge even though monophosphonucleotides (AMP and GMP) had little effect on activity. NADPH, but not NADH, substantially inhibited $NAD^+$-IDH activity, showing noncompetitive inhibition with isocitrate. Oxalacetate and ${\alpha}$-ketoglutarate showed competitive inhibition with isocitrate, while citrate and cis-aconitate showed mixed-noncompetitive inhibition with isocitrate. Inhibition by these substances ranged from 29 to 46% at 10 mM. The inhibitory effect of oxalacetate was increased synergistically by glyoxylate, which alone caused 31% uncompetitive inhibition at 10 mM, and a mixture of the two substances at 1 mM each showed 98% inhibition of $NAD^+$-IDH activity. The regulation of $NAD^+$-IDH in Pythium ultimum seems to be a complex process involving mitochondrial metabolites. The addition of glyoxylate (3 mM) and oxalacetate (3 mM) to the culture medium resulted in the production of 49% more lipid by P. ultimum.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.2
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• pp.207-214
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• 2009

This paper provides the analysis of economic theories about bundling in telecommunications service. First, the negative aspect of bundling is discussed. Second, the competitively neutral aspect of bundling which is counter response of negative effect is analyzed. Third, some variables affecting the bundling is investigated and the corresponding effect of bundling is discussed. The bundling can increase the social welfare under some circumstance while it sometimes decreases economic efficiency by detering the entry of competitive firms. Finally, regulatory approaches on bundling such as the criteria of bundling provision, the requirement of equal access, the discounting scheme ad a price control, ex anti regulation vs. ex post regulation, and the criteria of predatory pricing are provided.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.1
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• pp.16-22
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• 2015

As the development of Battery Energy Storage System(BESS) and the increasing of intermittent energy sources like wind power and photovoltaic, the application of BESS in load frequency control is considered as an effective method. To evaluate the effectiveness of BESS application in frequency control, we defined a governor free model of BESS to conduct dynamic simulation. Using the BESS dynamic model, we implemented the power system dynamic model including steam, gas and hydro turbine generators. In this paper we study the control performance of BESS in primary frequency control. The effect of BESS speed regulation rate and response time on governor free operation is investigated. In addition, we compared BESS from steam turbine generator in view point of frequency regulation.

• Korean Journal of Adult Nursing
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• v.19 no.3
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• pp.339-352
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• 2007

Purpose: The purpose of this study was to investigate the effect of weight control program on body composition(body mass index and waist-hip ratio), blood pressure, serum lipids(total cholesterol, triglyceride, high density lipoprotein and low density lipoprotein) and self-regulation behavior in obese college women. Methods: Forty seven obese subjects were divided into experimental(22) and control(25) groups. The weight control program lasting 12 weeks consisted of a traffic-light diet, jumping-rope exercises, and behavior modification methods with e-mail counseling. The data were collected from 29 March to 17 September of 2004. The variables were assessed before and after intervention for 12 weeks in two groups. Then, those were repeated after a 12 week suspension of intervention in the experimental group. The data were analysed by the SPSS computer program. Results: BMI, HDL, LDL and self-regulation behavior levels showed significant differences between the experimental and control groups. While there were no significant differences in waist-hip ratio, blood pressure, total cholesterol and triglyceride. Conclusion: The weight control program had a positive effect on obese college women, and can be used to control obesity.

• Journal of the Korean Society of School Health
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• v.30 no.3
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• pp.295-305
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• 2017

Purpose: This study was conducted to evaluate the effect of Mindfulness-based Emotion Management Training for adolescents immersed in self-harm behaviors. Methods: The participants were 61 middle school students located in Seoul. Thirty students were assigned to the Mindfulness-based Emotion Management Training (M-EMT) group and the other 31 students were assigned to the waitlist group. The students in the M-EMT group participated in a total of 12 sessions, twice a week, for 6 weeks. The modules of the program comprised of mindfulness for emotion, mindfulness for behavior/impulse, mindfulness for thought, and coping with self-harming behavior. The Distress Tolerance Scale, Deliberate Self-Harm Inventory, Cognitive Emotion Regulation Questionnaire, and Scale Suicidal Ideation were assessed at baseline and post-intervention. Results: Compared to the waitlist group, the intervention group exhibited a statistically significant improvement in distress tolerance and cognitive emotion regulation and a statistically significant reduction in self-harming behaviors and suicidal ideation. Conclusion: These results support the hypothesis that mindfulness-based emotional management training has a positive effect on reducing self-harming behaviors and enhancing distress tolerance and cognitive emotional regulation.

• Journal of ILASS-Korea
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• v.21 no.2
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• pp.71-77
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• 2016

Air pollutants nitrogen oxides are inevitably generated in the combustion reaction. Its amount trend is steadily increasing because the rapid modern industrialization and population growth. For this reason, NOx is controlled to reducing the harmful components in the exhaust gas. So Marine Environment Protection Committee (MEPC) take effect 'Tier I', 'Tier II' of air pollution regulation in 2005 and 2011 respectively. According to NOx emissions are strictly regulated management of the vessel through them. In addition, since 2016 the regulation enter into force in the next step 'Tier III' was confirmed by MEPC 66th committee. It's 80% enhanced emissions limits than the 'Tier I' Alternatively these emission regulation, research is actively being carried out about exhaust gas after-treatment methods through the vessel application of Selective Catalytic Reduction(SCR). Therefore depending on the basic specification of cell density according to the Area velocity, Space velocity, Linear velocity is studied the effects of NOx removal efficiency

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.583-584
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• 2015

Energy Storage System(ESS) can be used as several purposes such as uninterruptible power supply (UPS), frequency regulation, maximum load cut, and etc. This paper analyzes and simulates the reclosing operation in distribution system with ESS for frequency regulation and maximum load cut. To solve the effect from ESS, two sequences in reclosing process are added to conventional reclosing. The modelings and simulations of reclosing operation using EMTP/ATPDraw are performed.

• Journal of Auto-vehicle Safety Association
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• v.14 no.2
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• pp.90-95
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• 2022

Composite material is widely used in the automotive industries because it has excellent mechanical properties and is possible to reduce weight due to the low density. However, there is a new obstacle to meet environment regulation like Cu less or Cu free regulation for the friction material. Although it is strongly demanded, there are few research results about that unfortunately. Unless this problem is not solved properly, it is impossible to apply composite brake system to vehicle. In this paper, a new eco-friendly friction material for composite brake system is represented to respond these regulations. To do this, friction characteristics between existing low steel friction material and new eco-friendly friction material are verified to secure performances for brake system such as effect characteristic, fade characteristic and wear characteristic. And composite brake gets the equivalent or better performance compared to a low steel friction material. Finally, this result contributes to the study of major principles for the development of eco-friendly friction material in the future.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.6
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• pp.782-788
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• 2013

Chrysanthemum zawadskii Herbich var. latilobum Kitamura (Compositae), colloquially known "Gujulcho" in Korea, has been used in traditional medicine for the treatment of various diseases, including cough, common cold, bladder-related disorders, gastroenteric disorders, hypertension, and inflammatory diseases, such as pneumonia, bronchitis, pharyngitis, and rheumatoid arthritis (RA) However, the effect of Chrysanthemum zawadskii var. latilobum on breast cancer invasion is unknown. In this study, we investigated the inhibitory effect of Chrysanthemum zawadskii var. latilobum extract (CZE) on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced matrix metalloproteinase-9 (MMP-9) expression and cell invasion, as well as the molecular mechanisms involved in MCF-7 cells. CZE were not cytotoxic up to 100 ${\mu}g/ml$ concentration in the MCF-7 cell line. CZE decreased MMP-9 expression. TPA substantially increased NF-${\kappa}B$ DNA binding activity. Pre-treatment with CZE inhibited TPA-stimulated NF-${\kappa}B$ binding activity and NF-${\kappa}B$ related protein expression. To identify invasion ability of MCF-7 cells decreased by CZE, we used martrigel invasion assay. As a result, it is significantly decreased cell invasion. These results indicate that CZE-mediated inhibition of TPA-induced MMP-9 expression and cell invasion involves the suppression of the NF-${\kappa}B$ pathway in MCF-7 cells. Chrysanthemum zawadskii var. latilobum may have potential value in restricting breast cancer metastasis.

• Herbal Formula Science
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• v.24 no.3
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• pp.175-193
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• 2016

Objective : Diuretics are effective on the patients with hypertension and heart failure, as well as edema by regulating the function of kidney, which is key organ to maintain the balance of the different electrolytes in the body. The present review article is designed to review the diuretic effect of Korean medicinal prescription base on the experimental studies.Method : For this purpose, every article related to ‘diuresis’ and 'Korean medicinal prescription' were analysed from articles which published at domestic and international journals.Results : 1. Representative Korean medicine prescriptions showed diuretic effect along with electrolyte excretion were Oryeong-san, Paeryung-tang, Hwangryungbokryung-tang and Daeganghwal-tang. 2. Some Korean medicinal prescription including Oryeong-san, Jueryeong-tang, Sipcho-tang distribute diuresis through the inhibition of renin-angiotensin-system. 3. Oryeong-san, Bojungchiseup-tang had a diuretic effect on the down-regulation of aquaporin water channel in the renal collecting duct.Conclusion : Korean medicinal transcriptions have a diuretic effect through several types of mechanism such as along with electrolytes excretion, inhibition of renin-angiotensin system, and down-regulation of water channels.