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Complete Relaxation and Conformational Exchange Matrix (CORCEMA) Analysis of Saturation Transfer Difference (STD) NMR Spectra of Ligand-Protein Complexes

  • Krishna, N.Rama;Jayalakshmi, V.
    • Journal of the Korean Magnetic Resonance Society
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    • v.6 no.2
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    • pp.94-102
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    • 2002
  • An interesting recent application of intermolecular NOE experiment is the saturation transfer difference NMR(STD-NMR) method that is useful in screening compound libraries to identify bio-active ligands. This technique also identifies the group epitopes of the bound ligand in a reversibly forming protein-ligand complex. We present here a complete relaxation and conformational exchange matrix (CORCEMA) theory (Moseley et al., J. Magn. Reson. B, 108, 243-261 (1995)) applicable for the STD-NMR experiment. Using some ideal model systems we have analyzed the factors that influence the STD intensity changes in the ligand proton NMR spectrum when the resonances from some protons on the receptor protein are saturated. These factors will be discussed and some examples of its application in some model systems will be presented. This CORCEMA theory for STD-NMR and the associated algorithm are useful in a quantitative interpretation of the STD-NMR effects, and are likely to be useful in structure-based drug design efforts. They are also useful in a quantitative characterization of protein-protein (or protein-nucleic acid) contact surfaces from an intermolecular cross-saturation NMR experiment.

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Solution of OECD/NEA PWR MOX/UO2 benchmark with a high-performance pin-by-pin core calculation code

  • Hyunsik Hong;Jooil Yoon
    • Nuclear Engineering and Technology
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    • v.56 no.9
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    • pp.3654-3667
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    • 2024
  • Expanding upon the framework of the steady-state pin-by-pin 2D/1D decoupling method, a novel and highperformance pin-by-pin transient calculation method has been introduced. This transient method, consistent to the steady-state formulation, is designed for time-dependent calculations utilizing a 3D diffusion-based finite difference method (FDM). The inherent complexity of the large 3D problem is effectively managed by decoupling it into a series of planar (2D) and axial (1D) problems. In addition, tens of thousands of pin-cells are grouped into hundreds of boxes to reduce the computing burden for the 1D calculations without essential loss of the accuracy. Two-level coarse mesh finite difference (CMFD) formulation comprising multigroup nodewise CMFD and twogroup assemblywise CMFD is employed as well to accelerate the convergence. Errors originating from the pinlevel homogenization, energy group condensation, and the use of lower order calculation methods are simultaneously corrected by the pinwise super homogenization (SPH) equivalence factor. The transient method is evaluated with OECD/NEA PWR MOX/UO2 benchmark. Code-to-code comparison with the nTRACER direct whole core calculation code yielded highly satisfactory results for the transient scenario as well as the steady-state problems. Furthermore, comparative analyses with conventional nodal calculations show superiority of the pin-by-pin calculation.

Identifying the Facilitating Factors for Web-based Trading: A Case Study of Blockchain & Cryptocurrency

  • Sang Hoon Lee;Hyun-Seok Hwang;Su-Yeon Kim
    • Journal of Web Engineering
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    • v.21 no.6
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    • pp.1767-1792
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    • 2022
  • Blockchain, which is spotlighted as one of the core technologies in the Web 3.0 era, is being used as a tool for high security and decentralization. In addition, blockchain has been positioned as a core technology for services such as cryptocurrency, NFT, De-Fi, and metaverse, and has already provided high-quality services. In particular, cryptocurrency has shown rapid growth and has been receiving worldwide attention. Cryptocurrency is a web technology and has the property that it can be an investment target, and it is expected to develop further in the future. In this research, we analyzed factors influencing the intention to use cryptocurrency and structural causalities among the factors. We considered personal characteristics, characteristics of cryptocurrency itself, and social characteristic, and a research model has been established for an empirical study. In addition, a multi-group analysis was performed to identify differences between users and non-users. As a result of the analysis, it was found that some of the personal characteristics and cryptocurrency characteristics affect the intention to use. And in the case of non-users, it was found that not only personal and cryptocurrency characteristics, but also social characteristic influence their intention to use. The results of this research are expected to provide implications for cryptocurrency service providers and users, as well as institutions that establish related policies.

VINUS: A neutron transport solver based on the variational nodal method for reactor core analysis

  • Zhulun Li;Xubo Ma;Longxiao Ma;Teng Zhang;Zhirui Du
    • Nuclear Engineering and Technology
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    • v.56 no.10
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    • pp.4195-4206
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    • 2024
  • Compared to traditional transverse integration methods, the variational nodal method, with its unique advantages, is more suitable for high-fidelity calculations of reactor physics in reactors with complex geometries and finer detail descriptions. In this study, the basic theory of the variational nodal method was derived and the VINUS code is developed. The neutron solver based on this method is adaptable to various geometric models, and showcased the code's fundamental framework. On this basis, a set of self-designed macroscopic cross-section benchmarks, actual macroscopic cross-section benchmark VVER-440, and few-group microscopic cross-section benchmark RBEC-M for fast spectrum reactors were used to verify different functionalities of VINUS. The results were shown that VINUS code maintains good computational accuracy and convergence trends. For the VVER-440 benchmarks, the deviation of keff of VINUS from reference is less than 100 pcm, and the maximum power deviation is less than 4 %. For the RBEC-M, the deviation of keff is 125 pcm, and the maximum power deviation is less than 5 %. These outcomes collectively demonstrate the solver's potential for engineering applications in future advanced reactor designs.

A study on the applicability of simplified few-group GET (Generalized Equivalence Theory) to cylindrical molten salt fast reactor

  • Sungtaek Hong;Taesuk Oh;Yonghee Kim
    • Nuclear Engineering and Technology
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    • v.56 no.10
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    • pp.4207-4218
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    • 2024
  • One of the essential requirements for molten salt reactor (MSR) design is methodology for analyzing multiphysics phenomena, such as the behavior of liquid fuel. In the research of Molten Salt Fast Reactors (MSFRs), the Neutron Diffusion Equation (NDE) is widely employed. This study introduces a method to enhance the accuracy of neutronic analysis of MSFR using the NDE. Using the simple structure of MSFR and the characteristics of liquid nuclear fuel, it is intended to enable the application of the simple equivalence method, which is difficult to perform on the existing fast reactor. A straightforward yet effective approach named the simplified Generalized Equivalence Theory (simplified GET) is proposed for applying flux-volume-weighted homogenized cross-sections and representative Discontinuity Factor (DF) values obtained at material. This approach, while similar to the General Equivalence Theory (GET) method, significantly simplifies the enhancement of accuracy in reactor analysis, minimizing computational efforts. Our investigation spans from the initial core to the burned core, ensuring the applicability of this simple method throughout the reactor's operational life. The proposed method demonstrates promising results, offering a viable solution to improve the accuracy of NDE-based calculations in MSFRs.

The Press Coverage of the Cyber Defamation Laws: Framing Effects of Core Values and Attributional Patterns (사이버모욕죄 보도의 프레이밍 효과: 핵심 가치와 귀인 양식을 중심으로)

  • Hur, Suk-Jae;Min, Young
    • Korean journal of communication and information
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    • v.52
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    • pp.48-68
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    • 2010
  • In covering the controversies surrounding the so-called cyber defamation laws, the Korean press offered competitive frames in terms of values (security vs. freedom of speech) and attributional patterns (episodic vs. thematic attribution). By attending to core values and attributional patterns as two essential components of news frames, this study explored the cognitive and affective processes of value and attributional framing and their effects on issue opinion. According to a 3-group online experiment, first, it was found that core values increased the perceived importance of relevant beliefs, which further affected individuals' attitudes toward the laws. The affective effects of core values were also found marginally significant. The value of security increased the intensity of anger toward deviant netizens (so-called defamatory repliers), and it further increased individuals' support for the laws. It was not substantiated, however, that individualistic attribution, than social attribution, would provoke stronger anger toward defamatory repliers. Instead, episodic frames appeared to be more effective in driving issue opinion as indicated by the value frame.

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Analyzing the Effect of Argumentation Program for Improving Teachers' Conceptions of Evolution (교사들의 진화 개념 이해 향상을 위한 논변활동 프로그램 효과 분석)

  • Kwon, Jieun;Cha, Heeyoung
    • Journal of The Korean Association For Science Education
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    • v.35 no.4
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    • pp.691-707
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    • 2015
  • This study aims to develop biology teachers' education program based on argumentation activity about core concepts of evolution and to analyze the characteristics of core concepts of evolution learned during the program. The eight core concepts of evolution in this study were variation, heritability of variation, competition, natural selection, adaptation, differential reproductive rate of individuals, changes in genetic pool within a population, and macroevolution. The performances of teachers participating in the program were compared before and after argumentation activities; consisting of seven sessions on the eight core concepts of evolution. The process of the program was specially designed by learning cycle model for teacher education, consisting of seven phases: identification of the task, production of a tentative argument, small group's written argument, share arguments with the other groups, reflective discussion, final written argument, and organization by an instructor. Participants in the study were two pre-service biology teachers and four in-service biology teachers. The results suggest that biology teachers reduced the teleological explanation for biological evolution and improve its adequacy after the intervention. Teachers lacked the opportunity to discuss variation, heritability of variation, competition, and macroevolution because science textbooks lack information on the concepts of biological evolution. The results of this study suggest that because the argumentation program developed for teachers helps to improve understanding the concepts of evolution and to reduce inadequate conceptions in biology, teacher education programs using argumentation activity and eight core concepts of evolution will play a role for efficient evolution education for biology teachers.

Molecular Dynamics Simulation Study for Ionic Strength Dependence of RNA-host factor Interaction in Staphylococcus aureus Hfq

  • Lazar, Prettina;Lee, Yun-O;Kim, Song-Mi;Chandrasekaran, Meganathan;Lee, Keun-Woo
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1519-1526
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    • 2010
  • The behavior of peptide or protein solutes in saline aqueous solution is a fundamental topic in physical chemistry. Addition of ions can strongly alter the thermodynamic and physical properties of peptide molecules in solution. In order to study the effects of added ionic salts on protein conformation and dynamics, we have used the molecular dynamics (MD) simulations to investigate the behavior of Staphylococcus aureus Hfq protein under two different ionic concentrations: 0.1 M NaCl and 1.0 M NaCl in presence and absence of RNA (a hepta-oligoribonucleotide AU5G). Hfq, a global regulator of gene expression is highly conserved and abundant RNA-binding protein. It is already reported that in vivo the increase of ionic strength results in a drastic reduction of Hfq affinity for $Q{\beta}$ RNA and reduces the tendency of aggregation of Escherichia coli host factor hexamers. Our results revealed the crucial role of 0.1 M NaCl Hfq system on the bases with strong hydrogen bonding interactions and by stabilizing the aromatic stacking of Tyr42 residue of the adjacent subunits/monomers with the adenine and uridine nucleobases. An increase in RNA pore diameter and weakened compactness of the Hfq-RNA complex was clearly observed in 1.0 M NaCl Hfq system with bound RNA. Aggregation of monomers in Hfq and the interaction of Hfq with RNA are greatly affected due to the presence of high ionic strength. Higher the ionic concentration, weaker is the aggregation and interaction. Our results were compatible with the experimental data and this is the first theoretical report for the experimental study done in 1980 by Uhlenbeck group for the present system.

A Preliminary Survey Study on Standardization of the Core Seven Emotions Inventory-Short Form (CSEI-s) (핵심칠정척도 단축형의 표준화를 위한 예비적 설문 연구)

  • Jeesu Kim;Moon Joo Cheong;Do-Eun Lee;Yeoung Su Lyu;In-Chul Jung;Jeauk Kim;Hyung Won Kang
    • Journal of Oriental Neuropsychiatry
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    • v.34 no.3
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    • pp.125-139
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    • 2023
  • Objectives: This was a preliminary study to re-verify the reliability and validity of the Core Seven Emotions Inventory-Short Form (CSEI-s) and to establish standards for an objective scoring system such as T-scores and percentile for the normative group. Methods: Subjects were sampled through population-proportional regional allocation based on adults aged 20 or older and 65 or younger who voluntarily consented. Reliability was analyzed by performing an internal consistency (Cronbach's α) test and calculating means and standard deviations for each scale. The validity was analyzed between the CSEI-s and STAXI-K, SADS, COMOSWB, HADS, K-PANAS, Core emotions VAS. Results: The CSEI-s revealed notable gender discrepancies in aspects such as thought (思), fear (恐), and fright (驚), with women generally scoring higher than men. CSEI-s scores showed statistically significant differences in joy (喜) and thought (思) between those in their 20s and those in their 50s and 60s. As a result of the validity analysis, the seven-factor configuration was found to be statistically valid, and as a result of the correlation analysis with the coexistence scale, the correlation between each emotion and the seven emotions was found to be statistically significant. Cronbach's α for the CSEI-s was .891, showing statistically significant reliability. Conclusions: A preliminary study was conducted to standardize the shortened form of the Core Emotion Scale, and the reliability and validity were confirmed. A main survey of more people should be conducted in the future. Future results can contribute to revitalizing the development of oriental medicine evaluation tools and establishing an evidence base by standardizing the CSEI-s.

The Dutch RE;MIND Design's Conceptual and Critical Aesthetics of Use (네덜란드 RE;MIND 디자인의 개념적·비평적 사용미학)

  • Park, Young-Tae
    • Korean Institute of Interior Design Journal
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    • v.23 no.2
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    • pp.51-61
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    • 2014
  • Aesthetics of use for modern people can be regarded as being weighted toward universal and rational function since it has focused on an 'automation and efficiency' and 'smartness' in terms of technological and human engineering position. Thus, aesthetics of use as an individual agent has remained in minimal level. This study attempts to seek conceptual model of design regarding the behavior of users from the systematization of critical theories about the usability. To do that, 'HERTZAIN TALES' written by Anthony Dune and the concept and system of Droog Design have been used as a core standard. In line with the various experiments by artist groups such as Fluxus, Memphis group and the work of product semantics, and inherent characteristics of Droog design, which has surfaced from the 1990s, concepts that has mentioned in the Hertzain tales have been organized into main texts. By overcoming cognitive bias inherent in the material culture and by overcoming an existing usability based on immateriality and dialectic solution, the autonomy of critical design and instrumentality of Droog design have been systemized. By interpreting the design aspect of 12 pieces that have been submitted to the RE;MIND section, the core of this study, it has been confirmed that conceptual and critical design's aesthetics of use From the interpretation of the design aspect of 12 pieces that have been submitted to the RE;MIND section, the core of this study, it has been confirmed that conceptual and critical design's aesthetics of use has established the autonomy and independence of the behavior of users, created functional articulation of materials and secured new conceptual model and thus, could be an effective methodical clue for creating an emergent design.