• Title/Summary/Keyword: structural parameter

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The Effect of the Hydrogen Bond Network in the $S_1$-pocket on Catalytic Activity of Serine Protease, Achromobacter Protease I (API)

  • Lim, Seong-Il;Byun, Myung-Woo;Choi, Cheong
    • Journal of Microbiology and Biotechnology
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    • v.8 no.2
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    • pp.158-164
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    • 1998
  • Crystal structural analyses of the API-TLCK complex revealed that the ${\epsilon}$-amino group (NZ) of the lysyl part of TLCK forms hydrogen bonds with OD1 of $Asp^225$ which is a substrate specificity determinant of API, OG of $Ser^214$, O of $Ser^214$, OG1 of $Thr^189$, and O of $Thr^189$ l89/. The ${\beta}$-carboxyl oxygen of $Asp^225$ forms hydrogen bonds with the NE1 of $Trp^182$. From these observations, it is thought that besides $Asp^225$, $Thr^189$, $Ser^214$, and $Trp^182$ may also contribute to the steric specificity for lysine and high proteolytic activity of API. The side-chain hydroxyl groups of $Thr^189$ and $Ser^214$ were removed to elucidate the role of these hydrogen bonds in the $S_1$-pocket. The $k_{cat}$/$K_m$ of T189V, S214A, and T189V.S214A were decreased to 1/4, 1/3, and 1/46, respectively, of the value for native API. The decreased activities were mainly due to the increase of $K_m$. The CD and fluoroscence spectra of the three mutants were similar to those of wild-type API. With regards to the kinetic parameters ($K_i\;and\;k_2$) of mutants for the reaction involving TLCK and DFP, $k_2$decreased by increase of $K_1$ only. These results suggest that the decreased catalytic activity of these mutants is caused by the partial loss of the hydrogen bond network in the $S_1$-pocket. On the other hand, the similarity of enzymatic properties between W182F and the native enzyme suggests that the hydrogen bond between OD2 of $Asp^225$ and NE1 of $Trp^182$ is not directly related to the reaction of $Asp^225$ with the substrate.

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Analysis of Wind Velocity Profile for Calculation of Wind Pressure on Greenhouse (온실의 풍압력 산정을 위한 풍속의 수직분포 분석)

  • Jung, Seung-Hyeon;Lee, Jong-Won;Lee, Si-Young;Lee, Hyun-Woo
    • Journal of Bio-Environment Control
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    • v.24 no.3
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    • pp.135-146
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    • 2015
  • To provide the data necessary to determine the design wind speed for calculating the wind load acting on a greenhouse, we measured the wind speed below 10m height and analyzed the power law exponents at Buan and Gunwi. A wind speed greater than $5m{\cdot}s^{-1}$ is appropriate for calculating the power law exponent necessary to determine the wind speed distribution function according to height. We observed that the wind speed increased according to a power law function with increased height at Buan, showing a similar trend to the RDC and JGHA standards. Therefore, this result should be applied when determining the power law function for calculating the design wind speed of the greenhouse structure. The ordinary trend is that if terrain roughness increases the value of power law exponent also increases, but in the case of Gunwi the value of power law exponent was 0.06, which shows contrary value than that of the ordinary trend. This contrary trend was due to the elevations difference of 2m between tower installed and surrounding area, which cause contraction in streamline. The power law exponent started to decrease at 7 am, stopped decreasing and started to increase at 3 pm, and stopped increasing and remained constant at 12 pm at Buan. These changes correspond to the general change trends of the power law exponent. The calculated value of the shape parameter for Buan was 1.51, confirming that the wind characteristics at Buan, a reclaimed area near the coast, were similar to those of coastal areas in Jeju.

The Effects of The Parent Brand-Congruity on the Attitude to Expanded Brand (모 브랜드-일치성이 확장브랜드에 대한 태도에 미치는 영향)

  • Kang, Min-Jung;Hwang, Hee-Joong
    • Journal of Distribution Science
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    • v.17 no.2
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    • pp.77-89
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    • 2019
  • Purpose - This study presents the relationships between parent brand-self image congruence, parent brand -functional congruity, perceived fit between parent brand and extension product, and consumer's attitude toward extension product using the structural equation model. As for preceding concepts having a direct effect on consumer's attitude toward brand extension, the study focuses on parent brand-self image congruence and parent brand-functional congruity. It also looks at the effect of parent brand-self image congruence and parent brand-functional congruity on the consumer's attitude toward extension product and identifies if the perceived fit between parent brand and extension product is a concept playing a mediating role between parent brand-self image congruence or parent brand-functional congruity and consumer's attitude toward brand extension product. Research design, data, and Methodology - SPSS for Windows 18.0 and AMOS 18.0 were used for data analysis. Then, the Cronbach's α coefficient was obtained using SPSS for Windows 18.0 to measure reliability. In addition, the convergence and discriminative measures of the measured items were statistically verified using AMOS 18.0. Finally, we have validated a path model and a parameter model in which brand personality-self-matched attitude toward brand extension. Results - Studies have shown that the impact of parent brand-self image consistency and parent brand-functional consistency on the attitude of extended products was positive. Perceived fit between parent brand and extension products has been shown to play a role of intermediary between parent brand-self image congruence and consumer attitudes to extended products. However, perceived fit between parent brand and extension products did not play a role as intermediary between the parent brand-functional congruity and the attitude toward the extended product. Finally, in relation to the causal relationship between parent brand-congruity (self image/functionality) and attitudes to extended products. The effect of parent brand-functional coherency on attitudes toward extended products was found to be greater in groups with higher involvement than in those with lower involvement. Conclusions - Although few studies have been done on what variables mediated when parent brand-self image consistency and parent brand-functional coherency affect consumer attitude, this paper is significant in finding whether perceived fitness between the parent brand-congruity and the extension product is mediated.

Study on Relationship Between Intima Medial Thickness and the Plaque in Stroke Patients on Carotid Artery Sonography (뇌경색 환자에서 초음파로 측정한 경동맥 내막-중막두께와 죽상경화반의 관련성에 대한 연구)

  • Lee, Mi-Hwa;Kwon, Duk-Mun;Kang, Yeong-Han
    • Journal of radiological science and technology
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    • v.32 no.2
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    • pp.161-168
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    • 2009
  • The carotid intima-media thickness (IMT) is an early structural marker of the atherosclerotic process and is the only non-invasive test that is currently recommended by the American Heart Association for evaluation of the risk. However, use of this parameter has a limitation because it assumes uniform thickness throughout the blood vessel, whereas atherosclerosis is a focal phenomenon that is confined to intima. In fact, plaque can be found along the atherosclerotic blood vessels even though its value is unknown. The aim of this study is to analyze the carotid plaque and IMT in the stroke patients. We investigated the patients with ischemic stroke, who were admitted to the department of neurology at the Stroke Special Hospital from January to March 2008. After the carotid IMT and plaque were assessed by B-mode ultrasonography, IMT and carotid plaque to risk variables (age, sex) were analyzed. The distribution of CCA IMT was significantly different in terms of age (p = 0.004). Likewise, the distribution of carotid plaque was also significantly different in terms of age (p = 0.006). Carotid plaque was 69 and 92% in normal and abnormal CCA IMTs respectively. The results showed that the CCA IMT was closely associated with carotid plaque.

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Correlation Analysis of Body Parameters between Chuna Posture Analysis System and X-ray (추나체형진단기와 단순 방사선 검사로 측정된 신체 지표들간의 상관 분석)

  • Kim, Chang-Gon;Lee, Jin-Hyun;Min, Seon-Jeong;Kim, Byung-Sook;Song, Yung-Sun;Lee, Su-Kyung;Ko, Youn-Suk;Lee, Jung-Han
    • Journal of Korean Medicine Rehabilitation
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    • v.24 no.4
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    • pp.177-185
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    • 2014
  • Objectives This study analyzed the correlation between body parameters measured using X-ray and Chuna posture analysis system to determine their clinical value in diagnosing and evaluating skeletomuscular diseases. Methods X-ray and Chuna posture analysis system were performed for 105 patients to measure physical characteristics such as Interacromial angle, Pelvic obliquity angle, Structural leg length discrepancy (SLLD), Midpatella-midtalus angle (MMA) and Q-angle, Anterior head translation (AHT), Anterior superior iliac spine to posterior superior iliac spine angle (ASIS-PSIS angle), Interscapular angle, Scoliotic angle and Cobb's angle. Statistical analysis using statistical analysis techniques and Pearson correlation coefficients was performed to assess the body parameters obtained by X-ray and Chuna posture analysis system. Results Significant correlations were observed between the values for Interacromial angle, Pelvic obliquity angle, SLLD, MMA and Q-angle, AHT, ASIS-PSIS angle, Interscapular angle, Scoliotic angle and Cobb's angle obtained by X-ray and Chuna posture analysis system. Significant correlations were also observed between right MMA and left Q-angle as well as between left MMA and right Q-angle. Conclusions Chuna posture analysis system can be used instead of X-ray measure body parameters and perform posture analysis in clinical practice. This study's findings are expected to serve as a basis for further research on the clinical application of Chuna posture analysis system.

The Effect of Emotional labor of the members in private security firms on the job stress and validity of the organization (민간경비조직 구성원의 감정노동이 직무스트레스 및 조직유효성에 미치는 영향)

  • Cho, Cheol Kyu;Kim, Jin-Hwan;Jung, Sung-Sook
    • Convergence Security Journal
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    • v.14 no.6_2
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    • pp.73-81
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    • 2014
  • This study has an objective to analyze the causal relationship between the emotional labor of the members in the private security firms and its effect on their job stress and validity of the organization. To carry out the study, I established a population of private security guards working at the security firms in Seoul. Then a total of 700 question naires were sent out for the survey using the random sampling method of clusters. The study was carried out over about four months, from May, 2014 to September, 2014. A total of 676 questionnaires were used for the final data. 24 questionnaires were excluded either because they were not returned or contained extreme value. In this study, a statistical package of SPSSWIN 18.0 and AMOS 18.0 were used in the data analysis and the causal relationship was verified using the covariance structural equation. The analysis showed the emotional labor to have a positive effect on the validity of organization but a negative effect on the job stress at the statistical level of p<.001 and the hypothesis was adopted. The hypothesis regarding the job stress was also adopted because job stress was found to have a negative effect on the validity of organization at the statistical level of p<.001. In addition, job stress was found to have a negative effect on the relationship between the emotional labor and validity of organization at the statistical level of p<.001. As a result, the hypothesis about the job stress would function as the parameter was only partially adopted.

Stochastic response of suspension bridges for various spatial variability models

  • Adanur, Suleyman;Altunisik, Ahmet C.;Soyluk, Kurtulus;Dumanoglu, A. Aydin
    • Steel and Composite Structures
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    • v.22 no.5
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    • pp.1001-1018
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    • 2016
  • The purpose of this paper is to compare the structural responses obtained from the stochastic analysis of a suspension bridge subjected to uniform and partially correlated seismic ground motions, using different spatial correlation functions commonly used in the earthquake engineering. The spatial correlation function employed in this study consists of a term that characterizes the loss of coherency. To account for the spatial variability of ground motions, the widely used four loss of coherency models in the literature has been taken into account in this study. Because each of these models has its own characteristics, it is intended to determine the sensitivity of a suspension bridge due to these losses of coherency models which represent the spatial variability of ground motions. Bosporus Suspension Bridge connects Europe to Asia in Istanbul is selected as a numerical example. The bridge has steel towers that are flexible, inclined hangers and a steel box-deck of 1074 m main span, with side spans of 231 and 255 m on the European and Asian sides, respectively. For the ground motion the filtered white noise model is considered and applied in the vertical direction, the intensity parameter of this model is obtained by using the S16E component of Pacoima Dam record of 1971 San Fernando earthquake. An analytically simple model called as filtered white noise ground motion model is chosen to represent the earthquake ground motion. When compared with the uniform ground motion case, the results obtained from the spatial variability models with partial correlation outline the necessity to include the spatial variability of ground motions in the stochastic dynamic analysis of suspension bridges. It is observed that while the largest response values are obtained for the model proposed by Harichandran and Vanmarcke, the model proposed by Uscinski produces the smallest responses among the considered partially correlated ground motion models. The response values obtained from the uniform ground motion case are usually smaller than those of the responses obtained from the partially correlated ground motion cases. While the response values at the flexible parts of the bridge are totally dominated by the dynamic component, the pseudo-static component also has significant contributions for the response values at the rigid parts of the bridge. The results also show the consistency of the spatial variability models, which have different characteristics, considered in this study.

Semi-active storey isolation system employing MRE isolator with parameter identification based on NSGA-II with DCD

  • Gu, Xiaoyu;Yu, Yang;Li, Jianchun;Li, Yancheng;Alamdari, Mehrisadat Makki
    • Earthquakes and Structures
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    • v.11 no.6
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    • pp.1101-1121
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    • 2016
  • Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

In vitro Effect of High Osmolality on Plasma Membrane Activities in the Spermatozoa (In Vitro 고삼투압이 정자 원형질막의 Protein Tyrosine Phosphorylation에 미치는 영향)

  • 오영근;장재호;최인호;정노팔;신형철;곽병주
    • Biomedical Science Letters
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    • v.6 no.4
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    • pp.237-244
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    • 2000
  • It has been reported that plasma membrane activity of the spermatozoa may be susceptible to be influenced by extracellular osmolality and such membranous changes involve infracellular molecular changes, special regard to the structure of membranous lipids, and the accompanying ion-channel of which are closely related with their fluidity of $Ca^{2+}$ and HCO$^{-}_{3}$. It is of common recognition that a certain kind of sterol acceptor player an important to induce lipid fluctuation of the sperm plasma membrane which have been influenced by BSA administration and came in effect to outflow of cholesterol from the spermatozoa and resulted in changes of ionic fluidity to facilitate adenylyl cyclase, and to induce protein tyrosine phosphorylation by increase of cAMP and activation of PKA. Thus it seems likely that an augmentation of the acrosomal reaction is closely related with protein tyrosine phosphorylation. The following experimental results were obtained in the present study; Under the high osmolality conditions, the spermatozoa motility declined significantly and the structural change of the plasma membrane diminished to confirm that the response degrees to the osmolality depended upon the water transfer volume through the plasma membrane and the changes of cellular volume. Those experimental results suggest that a physiological parameter such as low temperature condition played an important role for presentation of spermatozoa and that inducement of spermatozoa activation for reinforcement of protein tyrosine phosphorylation. On the other hand, it seemed likely that the BSA administration as one of sterol accepters might represent a key role also under the high osmolality condition and their result also suggests that osmolality change, special regard to high osmolality condition may play an important role also in the processes of signal transmission.

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A Molecular Dynamics Simulation Study of Hydroxyls in Dioctahedral Phyllosilicates (분자동역학 시뮬레이션을 이용한 이팔면체 점토광물 수산기 연구)

  • Son, Sangbo;Kwon, Kideok D.
    • Journal of the Mineralogical Society of Korea
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    • v.29 no.4
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    • pp.209-220
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    • 2016
  • Clay minerals are a major player to determine geochemical cycles of trace metals and carbon in the critical zone which covers the atmosphere down to groundwater aquifers. Molecular dynamics (MD) simulations can examine the Earth materials at an atomic level and, therefore, provide detailed fundamental-level insights related to physicochemical properties of clay minerals. In the current study, we have applied classical MD simulations with clayFF force field to dioctahedral clay minerals (i.e., gibbsite, kaolinite, and pyrophyllite) to analyze and compare structural parameters (lattice parameter, atomic pair distance) with experiments. We further calculated vibrational power spectra for the hydroxyls of the minerals by using the MD simulations results. The MD simulations predicted lattice parameters and interatomic distances respectively deviated less than 0.1~3.7% and 5% from the experimental results. The stretching vibrational wavenumber of the hydroxyl groups were calculated $200-300cm^{-1}$ higher than experiment. However, the trends in the frequencies among different surface hydroxyl groups of each mineral was consistent with experimental results. The angle formed by the surface hydroxyl group with the (001) plane and hydrogen bond distances of the surface hydroxyls were consistent with experimental result trends. The inner hydroxyls, however, showed results somewhat deviated from reported data in the literature. These results indicate that molecular dynamics simulations with clayFF can be a useful method in elucidating the roles of surface hydroxyl groups in the adsorption of metal ions to clay minerals.