• Title/Summary/Keyword: Functional connectivity

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Interactivity of Neural Representations for Perceiving Shared Social Memory

  • Ahn, Jeesung;Kim, Hye-young;Park, Jonghyun;Han, Sanghoon
    • Science of Emotion and Sensibility
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    • v.21 no.3
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    • pp.29-48
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    • 2018
  • Although the concept of "common sense" is often taken for granted, judging whether behavior or knowledge is common sense requires a complex series of mental processes. Additionally, different perceptions of common sense can lead to social conflicts. Thus, it is important to understand how we perceive common sense and make relevant judgments. The present study investigated the dynamics of neural representations underlying judgments of what common sense is. During functional magnetic resonance imaging, participants indicated the extent to which they thought that a given sentence corresponded to common sense under the given perspective. We incorporated two different decision contexts involving different cultural perspectives to account for social variability of the judgments, an important feature of common sense judgments apart from logical true/false judgments. Our findings demonstrated that common sense versus non-common sense perceptions involve the amygdala and a brain network for episodic memory recollection, including the hippocampus, angular gyrus, posterior cingulate cortex, and ventromedial prefrontal cortex, suggesting integrated affective, mnemonic, and social functioning in common sense processing. Furthermore, functional connectivity multivariate pattern analysis revealed that interactivity among the amygdala, angular gyrus, and parahippocampal cortex reflected representational features of common sense perception and not those of non-common sense perception. Our study demonstrated that the social memory network is exclusively involved in processing common sense and not non-common sense. These results suggest that intergroup exclusion and misunderstanding can be reduced by experiencing and encoding long-term social memories about behavioral norms and knowledge that act as common sense of the outgroup.

Spectral analysis of brain oscillatory activity (뇌파의 주파수축 분석법)

  • Min, Byoung-Kyong
    • Korean Journal of Cognitive Science
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    • v.20 no.2
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    • pp.155-181
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    • 2009
  • Psychophysiologists are often interested in the EEG signals that accompany certain psychological events. When one is interested in a time series of event-related changes in EEG, one focuses on examining how the waveforms recorded at individual electrode sites vary over time across one or more experimental conditions. This is an analysis of event-related potentials (ERPs). In addition to such a classical EEG analysis in the time domain, the EEG measures can be investigated in the frequency domain. Moreover, it has been demonstrated that spectral analyses can often yield significant insight into the functional cognitive correlations of the signals. Therefore, this review paper tries to summarize essential concepts (e.g. phase-locking) and conventional methods (e.g. wavelet transformation) for understanding spectral analyses of brain oscillatory activity. Phase-coherence is also introduced in relation to functional connectivity of the brain.

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Combined Application Effects of Arbuscular Mycorrhizal Fungi and Biochar on the Rhizosphere Fungal Community of Allium fistulosum L.

  • Chunxiang Ji;Yingyue Li;Qingchen Xiao;Zishan Li;Boyan Wang;Xiaowan Geng;Keqing Lin;Qing Zhang;Yuan Jin;Yuqian Zhai;Xiaoyu Li;Jin Chen
    • Journal of Microbiology and Biotechnology
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    • v.33 no.8
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    • pp.1013-1022
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    • 2023
  • Arbuscular mycorrhizal fungi (AMF) are widespread soil endophytic fungi, forming mutualistic relationships with the vast majority of land plants. Biochar (BC) has been reported to improve soil fertility and promote plant growth. However, limited studies are available concerning the combined effects of AMF and BC on soil community structure and plant growth. In this work, a pot experiment was designed to investigate the effects of AMF and BC on the rhizosphere microbial community of Allium fistulosum L. Using Illumina high-throughput sequencing, we showed that inoculation of AMF and BC had a significant impact on soil microbial community composition, diversity, and versatility. Increases were observed in both plant growth (the plant height by 8.6%, shoot fresh weight by 12.1%) and root morphological traits (average diameter by 20.5%). The phylogenetic tree also showed differences in the fungal community composition in A. fistulosum. In addition, Linear discriminant analysis (LDA) effect size (LEfSe) analysis revealed that 16 biomarkers were detected in the control (CK) and AMF treatment, while only 3 were detected in the AMF + BC treatment. Molecular ecological network analysis showed that the AMF + BC treatment group had a more complex network of fungal communities, as evidenced by higher average connectivity. The functional composition spectrum showed significant differences in the functional distribution of soil microbial communities among different fungal genera. The structural equation model (SEM) confirmed that AMF could improve the microbial multifunctionality by regulating the rhizosphere fungal diversity and soil properties. Our findings provide new information on the effects of AMF and biochar on plants and soil microbial communities.

Prediction of Ultra-High ON/OFF Ratio Nanoelectromechanical Switching from Covalently Bound $C_{60}$ Chains

  • Kim, Han Seul;Kim, Yong-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.645-645
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    • 2013
  • Applying a first-principles computational approach combining density-functional theory and matrix Green's function calculations, we have studied the effects [2+2] cycloaddition olligormerization of fullerene $C_{60}$ chains on their junction charge transport properties. Analyzing first the microscopic mechanism of the switching realized in recent scanning tunneling microscope (STM) experiments, we found that, in agreement with experimental conclusions, the device characteristics are not significantly affected by the changes in electronic structure of $C_{60}$ chains. It is further predicted that the switching characteristics will sensitively depend on the STM tip metal species and the associated energy level bending direction in the $C_{60}-STM$ tip vacuum gap. Considering infinite $C_{60}$ chains, however, we confirm that unbound $C_{60}$ chains with strong orbital hybridizations and band formation should in principle induce a much higher conductance state. We demonstrate that a nanoelectromechanical approach in which the $C_{60}-STM$ tip distance is maintained at short distances can achieve a metal-independent and drastically improved switching performance based on the intrinsically better electronic connectivity in the bound $C_{60}$ chains.

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Accurate Representation of Light-intensity Information by the Neural Activities of Independently Firing Retinal Ganglion Cells

  • Ryu, Sang-Baek;Ye, Jang-Hee;Kim, Chi-Hyun;Goo, Yong-Sook;Kim, Kyung-Hwan
    • The Korean Journal of Physiology and Pharmacology
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    • v.13 no.3
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    • pp.221-227
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    • 2009
  • For successful restoration of visual function by a visual neural prosthesis such as retinal implant, electrical stimulation should evoke neural responses so that the informat.ion on visual input is properly represented. A stimulation strategy, which means a method for generating stimulation waveforms based on visual input, should be developed for this purpose. We proposed to use the decoding of visual input from retinal ganglion cell (RGC) responses for the evaluation of stimulus encoding strategy. This is based on the assumption that reliable encoding of visual information in RGC responses is required to enable successful visual perception. The main purpose of this study was to determine the influence of inter-dependence among stimulated RGCs activities on decoding accuracy. Light intensity variations were decoded from multiunit RGC spike trains using an optimal linear filter. More accurate decoding was possible when different types of RGCs were used together as input. Decoding accuracy was enhanced with independently firing RGCs compared to synchronously firing RGCs. This implies that stimulation of independently-firing RGCs and RGCs of different types may be beneficial for visual function restoration by retinal prosthesis.

A Study on NMEA 2000 based two-dimensional Ultrasonic Anemometer (NMEA 2000 기반 2차원 초음파 풍향 풍속계에 관한 연구)

  • Kim, Jong-Hyun;Park, Dong-Hyun;Kim, Kyung-Yup;Yu, Yung-Ho
    • Journal of Advanced Navigation Technology
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    • v.15 no.1
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    • pp.25-31
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    • 2011
  • Recently NMEA 2000 protocol is familiarized as a standard real time instrument network of SOLAS ship. This paper is studied to develop NMEA 2000 based two-dimensional ultrasonic anemometer which is core device for navigation as a sensor of wind speed and direction using ultrasonic including temperature and barometer. Developed system is connected to NMEA 2000 network which is composed of various kinds of merchandised NMEA 2000 device such as depth gauge, speed gauge, GPS device etc. to test connectivity with other NMEA 2000 device and functional test are carried out as weather station in comparison with other merchandised weather station which are developed advanced foreign company to ascertain usability as a weather station on board.

A Study of Development ODBC Driver for Multimedia Data Processing (멀티미디어 데이터 처리를 위한 ODBC 드라이버 개발에 관한 연구)

  • 이말례;박일록
    • Journal of the Korea Society of Computer and Information
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    • v.3 no.3
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    • pp.23-30
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    • 1998
  • The ODBC(Open Database Connectivity) is particularly efficient in the dynamic client/server environment. Besides, the ODBC provides the functions that can handle multimedia data. Due to this feature, we are able to use the DBMS that supports the ODBC as a multimedia server. In this thesis, we describe the development of the ODBC driver for Relational DBMS. The Relational DBMS ODBC Driver consists of the client module and the server module. The client module is called the SRM(Server Request Module) and the server module is CSM(Client Service Module). These two modules are connected through the network module called the NSM(Network Service Module). We have conducted both the functional and the interoperability test of our ODBC Driver It turned out that the ODBC driver operated with these client DBMS tools successfully. In all, due to our development of the Relational DBMS ODBC Driver, DBMS is now capable of processing multimedia data and supporting the client applications including the DBMS tools.

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A Study on the functional Charaterictics of Apparel CAD Systems (어패럴 CAD 시스템 기능적 특성에 관한 연구)

  • 조진숙
    • Journal of the Korean Home Economics Association
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    • v.35 no.5
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    • pp.249-264
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    • 1997
  • The purpose of this study was to provide the reference information for user and potential users of apparel CAD system is Korea. Two interviews were carried out for the study. The apparel CAD system of Assyst, Gerber and Yuka was selected for technical comparative study. The results were as follows: 1. The future development of the apparel CAD system is the transfer of the developed pattern design from a 3D design system and of CIM concept. 2. The share of data is working closely in a module function. So the Assyst system provide connectivity and communication between all apparel CAD system's module and other automation programs. This system is suitable for CIM production line. 3. The Gerber system is developed the Apparel CAD system which is given by the CAM system's technical ability. This system is given high insurance of ability to the service and data transportation with other systems from users in the Korea. 4. The Yuka system is developed pattern making by the Apparel CAD system. This system's different methods which is compared with other systems are the split grading and auto pattern making. So this system is suitable for users which want to product many items and a little amount garment by using the Apparel CAD system.

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Engineering Theory: A Conversational Bridge Between Theoreticians and Practitioners in Discussion of Curriculum Development and Dissemination as Used in the DASH Program

  • Pottenger III, Francis M.;Son, Yeon-A;Kim, Joo-Hoon;Park, Hyun-Ju
    • Journal of The Korean Association For Science Education
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    • v.24 no.4
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    • pp.758-773
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    • 2004
  • This paper advances the thesis that the barrier separating curriculum theorists and practitioners is more than a difference in experiential and methodological orientation and is in part a product of a lack of appreciation of the complexities involved in curriculum development and dissemination. Discussed here is the possible use of engineering theory to facilitate meaningful communication and understanding about products and development. This work is an extension of the observation that curriculum development and dissemination can be characterized as an engineering process and shows how engineering theory provides connectivity between the multiple embedded domains of theory and of practice. To illustrate the thesis this paper offers an analysis of the Developmental Approaches in Science, Health, and Technology (DASH) program that has employed engineering theory in curriculum construction and dissemination. In this study, the role and place of engineering theory as applied to the DASH program is discussed to show how the components were designed and assembled into a fully functional curriculum and dissemination system. Engineering theory is presented as an interfacing organizer with the potential to facilitate meaningful communication between theorists and practitioners.

Statistical analysis issues for neuroimaging MEG data (뇌영상 MEG 데이터에 대한 통계적 분석 문제)

  • Kim, Jaehee
    • The Korean Journal of Applied Statistics
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    • v.35 no.1
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    • pp.161-175
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    • 2022
  • Oscillatory magnetic fields produced in the brain due to neuronal activity can be measured by the sensor. Magnetoencephalography (MEG) is a non-invasive technique to record such neuronal activity due to excellent temporal and fair amount of spatial resolution, which gives information about the brain's functional activity. Potential utilization of high spatial resolution in MEG is likely to provide information related to in-depth brain functioning and underlying factors responsible for changes in neuronal waves in some diseases under resting state or task state. This review is a comprehensive report to introduce statistical models from MEG data including graphical network modelling. It is also meaningful to note that statisticians should play an important role in the brain science field.