• Title/Summary/Keyword: Asymmetry effect

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19F NMR Investigation of F1-ATPase of Escherichia coli Using Fluorinated Ligands

  • Jung, Seun-Ho;Kim, Hyun-Won
    • BMB Reports
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    • v.31 no.1
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    • pp.44-47
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    • 1998
  • Asymmetry amongst nucleotide binding sites of Escherichia coli $F_1$-ATPase was examined using $^{19}F$ NMR signal from fluorinated analogs of adenine nucleotides bound to nucleotide binding sites. ADP-$CF_2-{PO_3}^{2-}$ showed no inhibitory effect to $F_1$-ATPase. But ADP-CHF-${PO_3}^{2-}$ (racemic mixture) showed competitive inhibition of $F_1$-ATPase with $K_i$ of $60\;{\mu}m$. ADP-CHF-${PO_3}^{2-}$ shows only negligible binding to $EF_1$ in the absence of $Mg^2+$. With the addition of $Mg^2+$ to the medium, the $^{19}F$ resonance of free ADP-CHF-${PO_3}^{2-}$ disappeared and the new broad resonances appeared. Appearance of more than two new asymmetric resonances following the binding of ADP-CHF-${PO_3}^{2-}$ to $EF_1$ may indicate that at least one of the isomers showed split resonances. This may suggest that the region between ${\alpha}$-and ${\beta}$-phosphate of ADP-CHF-${PO_3}^{2-}$ which is bound to catalytic sites is experiencing a different environment at different sites.

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Estimating volatility of American tourist demand with a pleasure purpose in Korea inbound tourism market (방한 미국여행객의 국제 수요변동성 분석)

  • Kim, Kee-Hong
    • International Commerce and Information Review
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    • v.10 no.1
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    • pp.395-414
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    • 2008
  • The objective of this study is to introduce the concepts and theories of conditional heteroscedastic volatility models and the news impact curves and apply them to the Korea inbound tourism market. Three volatility models were introduced and used to estimate the conditional volatility of monthly arrivals of inbound tourists into Korea and news impact curves according to the three models. Results of this study are as follows. As the proportion of American tourists occupied a large amount of Korea inbound tourism market, the markets' forecasting is very important. The news impact curves which used EGARCH model (1,1) and TGARCH model(1,1), with data on these tourists to Korea showed an asymmetry effect of volatility. It was common that bad news means that it was estimated more sensitively than good news. From these results, we will notice that American tourists who visited Korea only for tourism are affected by good news. The result suggests that the Korea government and tourism industry should pay more attention to changes in the tourism environment following bad news because conditional volatility increases more when a negative shock occurs than when a positive shock occurs.

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Influence of Global versus Local Rating Agencies to Japanese Financial Firms

  • Han, Seung Hun;Reinhart, Walter J.;Shin, Yoon S.
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.4
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    • pp.9-20
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    • 2018
  • Global rating agencies, such as Moody's and S&P, have assigned credit ratings to corporate bonds issued by Japanese firms since 1980s. Local Japanese rating agencies, such as R&I and JCR, have more market share than the global raters. We examine the yield spreads of 1,050 yen-denominated corporate bonds issued by financial firms in Japan from 1998 to 2014 and find no evidence that bonds rated by at least one global agency are associated with a significant reduction in the cost of debt as compared to those rated by only local rating agencies. Unlike non-financial firms, the reputation effect of global rating agencies does not exist for Japanese financial firms. We also observe that firms with less information asymmetry are more likely to acquire ratings from Moody's or S&P. Additionally, the firm's financial profile does not affect its choice to seek out ratings from global raters. Our findings are contradictory to those by Han, Pagano, and Shin (2012), who employ bonds issued by non-financial firms in Japan. Our conjecture is that the asymmetric nature of financial firms makes investors less likely to depend on a credit risk assessment by rating agencies in determining the yields of new bonds.

The Effect of Masticatory Muscle Fatigue on the Occlusal Contact Stability and Masticatory Muscle Actibities (저작근의 피로가 치아접촉안정성 및 저작근활성에 미치는 효과)

  • Hye-Yeong Kim;Sun-Ha Kim;Jae-Kap Choi
    • Journal of Oral Medicine and Pain
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    • v.17 no.1
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    • pp.41-50
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    • 1992
  • The authors performed a experimental study to evaluate the effects of masticatory muscle fatigue on tooth contact and masticatory muscle activity in 26 normal healthy women. The experimental masticatory muscle fatigue was induced by unilateral biting of 5kg force on mandibular first molar. The results were as follows : 1. The initial symptom related to muscle fatigue pain appeared in 85.19 seconds of isometric contraction and the endurance time of isometric contraction was 203.15 seconds. 2. The pain occurred more frequently in masseter region than in temporal region. In masseter pain the incidence was almost equal between both sides, whereas the temporal pain was more in contralateral side. 3. The spontaneity and the symmetry of tooth contact during maximum clenching were reduced after isometric unilateral biting. 4. After induction of experimental muscle fatigue, the EMG activities of masseter muscles of both sides and ipsilateral temporal muscle showed the tendency of decreasing activities. 5. The asymmetry indicies of masseter and temporal muscles were reduced after isometric bilateral biting.

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Effect of GABA Antagonist in the Monocular Optokinetic Nystagmus of the Chicken (닭의 Monocular Optokinetic Nystagmus에서 GABA Antagonist 효과)

  • 김명순
    • The Korean Journal of Zoology
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    • v.33 no.3
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    • pp.247-254
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    • 1990
  • Chicken monocular head and eye optokinetic nystagmus (OKN) were observed by coil recordings after intravitreal administration of GABA antagonists (picrotoxin and bicuculline) into the opened and closed eye. Before injection of drugs the chicken displayed an OKN for T-N stimulation being more efficient in evoking this visuomotor reflex than for N-T stimulation. The injection of GABA antagonist into the opened eye provoked a decrease or disappearance of the head and eye OKN. On the other hand, the injection of GABA antagonist into the closed eye, the head and eye OKN augmented. Thus, GABA antagonist abolished the directional asymmetry of the head and eye OKN, indicating the involvement of GABAergic mechanisms in the inhibition of the N-T component of the monocular OKN.

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The study on factors a special feature and the intention to use Traceability System (Traceability System 특징적 요인과 이용의도에 관한 실증연구)

  • Kang, Bong-Jae;Koh, Seok-Young;Koh, Wan-Ki
    • Journal of the Korea Society of Computer and Information
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    • v.13 no.3
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    • pp.211-224
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    • 2008
  • Occurrences of large-scale food-related mishaps around the globe are degrading the safety and confidence on food items. This can be said to result from problems such as information asymmetry between the supplier and the consumer(information user). It makes it difficult to confirm product-related information including who produced an item how, what manufacturing process was involved, and how the product was distributed, and deal with a food-related trouble. The research verified and analyzed what has an effect on the intention to use Traceability System when the user uses information service.

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Impact of Informational Justice on Pharmaceutical Enterprises

  • LEE, Changjoon;HA, Byoung-Chun;LIM, So-Youn
    • Journal of Distribution Science
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    • v.18 no.8
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    • pp.55-64
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    • 2020
  • Purpose: This paper addresses issues that concern business-to-business marketing, namely informational justice in the supply chain or organizations. As previously reported by other studies, there is information asymmetry in organizations. The present study explores and addresses this in the medical industry, aiming to investigate how informational justice relates to information quality or logistics performance in the medical industry. This study also suggests a method for development of informational justice in medicine-related fields. Design, methodology, approach: The hypothesis and model were developed through a review of the literature. To this end, we surveyed 293 valid survey samples collected from occupational pharmacists and used structural equation modelling for analysis. Findings: The results of the empirical analysis of the hypotheses showed that symmetric sharing of information between pharmacists and employees of pharmaceutical companies has a positive effect on the perceived quality. Moreover, the results showed that quality information has a positive impact on logistics performance, whereas informational justice does not. Conclusions, implications: If information and explanations are exchanged fairly, information and logistics performance-as well as operational expenses-will be enhanced. Furthermore, our study has immense implications outside of academic applications since it suggests practical solutions to government and medical industry employees.

Numerical Comparison of Thermalhydraulic Aspects of Supercritical Carbon Dioxide and Subcritical Water-Based Natural Circulation Loop

  • Sarkar, Milan Krishna Singha;Basu, Dipankar Narayan
    • Nuclear Engineering and Technology
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    • v.49 no.1
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    • pp.103-112
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    • 2017
  • Application of the supercritical condition in reactor core cooling needs to be properly justified based on the extreme level of parameters involved. Therefore, a numerical study is presented to compare the thermalhydraulic performance of supercritical and single-phase natural circulation loops under low-to-intermediate power levels. Carbon dioxide and water are selected as respective working fluids, operating under an identical set of conditions. Accordingly, a three-dimensional computational model was developed, and solved with an appropriate turbulence model and equations of state. Large asymmetry in velocity and temperature profiles was observed in a single cross section due to local buoyancy effect, which is more prominent for supercritical fluids. Mass flow rate in a supercritical loop increases with power until a maximum is reached, which subsequently corresponds to a rapid deterioration in heat transfer coefficient. That can be identified as the limit of operation for such loops to avoid a high temperature, and therefore, the use of a supercritical loop is suggested only until the appearance of such maxima. Flow-induced heat transfer deterioration can be delayed by increasing system pressure or lowering sink temperature. Bulk temperature level throughout the loop with water as working fluid is higher than supercritical carbon dioxide. This is until the heat transfer deterioration, and hence the use of a single-phase loop is prescribed beyond that limit.

The Effect of Trailing Wake Asymmetry on a Propeller Blade Forces in Inclined Inflow (비대칭 후류를 고려한 경사축 추진기의 유동해석)

  • Sang-Woo Pyo
    • Journal of the Society of Naval Architects of Korea
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    • v.35 no.1
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    • pp.24-31
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    • 1998
  • Unsteady propeller blade forces arising from shaft inclination have been found to be an important contribution tn total blade forces. The position of the wake relative to a blade oscillates with the first blade frequency, thus giving rise to unsteady blade forces which is significant relative to the forces produced directly by flow inclination. In order to find a wake geometry due to shaft inclination, a non-axisymmetric wake model is developed and applied to a specific case, which has experimental values. Predicted cavity shapes and unsteady forces acting on the blades of an inclined shaft propeller are compared to those predicted by other numerical methods, as well as those measured in experiments.

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Damage detection using the improved Kullback-Leibler divergence

  • Tian, Shaohua;Chen, Xuefeng;Yang, Zhibo;He, Zhengjia;Zhang, Xingwu
    • Structural Engineering and Mechanics
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    • v.48 no.3
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    • pp.291-308
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    • 2013
  • Structural health monitoring is crucial to maintain the structural performance safely. Moreover, the Kullback-Leibler divergence (KLD) is applied usually to asset the similarity between different probability density functions in the pattern recognition. In this study, the KLD is employed to detect the damage. However the asymmetry of the KLD is a shortcoming for the damage detection, to overcoming this shortcoming, two other divergences and one statistic distribution are proposed. Then the damage identification by the KLD and its three descriptions from the symmetric point of view is investigated. In order to improve the reliability and accuracy of the four divergences, the gapped smoothing method (GSM) is adopted. On the basis of the damage index approach, the new damage index (DI) for detect damage more accurately based on the four divergences is developed. In the last, the grey relational coefficient and hypothesis test (GRCHT) is utilized to obtain the more precise damage identification results. Finally, a clear remarkable improvement can be observed. To demonstrate the feasibility and accuracy of the proposed method, examples of an isotropic beam with different damage scenarios are employed so as to check the present approaches numerically. The final results show that the developed approach successfully located the damaged region in all cases effect and accurately.