• Mass Spectrometry Letters
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• v.11 no.3
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• pp.41-51
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• 2020

Microbes influence many aspects of human life from the environment to health, yet evaluating their biological processes at the chemical level can be problematic. Mass spectrometry imaging (MSI) enables direct evaluation of microbial chemical processes at the atomic to molecular levels without destruction of valuable two-dimensional information. MSI is a label-free method that allows multiplex spatiotemporal visualization of atomic- or molecular-level information of microbial and microberelated samples. As a result, microbial MSI has become an important field for both mass spectrometrists and microbiologists. In this review, basic techniques for microbial MSI, such as ionization methods and analyzers, are explored. In addition, we discuss practical applications of microbial MSI and various data-processing techniques.

• Proceedings of the KOSOMBE Conference
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• v.1998 no.11
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• pp.219-220
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• 1998

Although a single-element synthetic aperture system can produce high-resolution beam profile, it is not a highly practical system because of its low signal to noise ratio against conventional system's. A multi-element synthetic aperture processing has been proposed with defocusing in this paper. A multi element subaperture defocused to emulate a single element spatial response with high acoustic power. The results have higher signal to noise and better contrast resolution than conventional synthetic aperture method.

• Applied Microscopy
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• v.44 no.3
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• pp.83-87
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• 2014

Electron tomography (ET) is a useful tool to investigate three-dimensional details based on virtual slices of relative thick specimen, and it requires complicated procedures consisted of image acquisition steps and image processing steps with computer program. Although the complicated step, this technique allows us to overcome some limitations of conventional transmission electron microscopy: (1) overlapping of information in the ultrathin section covering from 30 nm to 90 nm when we observe very small structures, (2) fragmentation of the information when we study larger structures over 100 nm. There are remarkable biological findings with ET, especially in the field of neuroscience, although it is not popular yet. Understanding of behavior of synaptic vesicle, active zone, pooling and fusion in the presynaptic terminal have been enhanced thanks to ET. Some sophisticated models of postsynaptic density with ET and immune labeling are introduced recently. In this review, we introduce principles, practical steps of ET and some recent researches in synapse biology.

• Journal of Biomedical Engineering Research
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• v.22 no.4
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• pp.331-338
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• 2001

In this paper, we have proposed a new computer retina model reflecting the mechanism of transient amacrine cell on the basis of a conventional computer retina model to understand mechanism of visual information processing. The conventional computer retina model contained most of mechanism for other retina models and it was verified with the physiological data. However, we found that a conventional computer retina model doesn't have the mechanism of amacrine cell that was likely to respond to moving stimulus. In proposed model, therefore, a conventional computer model that considered from photoreceptors to bipolar cells and a new computer model that considered for transient amacrine cell and ganglion cell was combined. As we compared the physiological data with the results of computer simulation of transient amacrine cell about fixed stimulus and moving stimulus, we confirmed that the proposed new computer retina model was normally operated.

• Proceedings of the IEEK Conference
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• 2000.07b
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• pp.615-618
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• 2000

A number of studies have recently been made on hardware for a biological neuron f3r application with information processing functions of neural networks. We have been trying to produce hardware from the viewpoint that development of a new hardware neuron model is one of the important problems in the study of neural networks. In this paper, we first discuss the circuit structure of a pulse-type hardware neuron model with the enhancement-mode MOSFETs (E-MOSFETs). And we construct a pulse-type hardware neuron model using I-MOSFETs. As a result, it is shown that our proposed new model can exhibit firing phenomena even if the power supply voltage becomes less than 1.5[V]. So it is verified that our model is profitable for IC.

• Proceedings of the Korean Information Science Society Conference
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• 2003.04a
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• pp.106-108
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• 2003

Human Genome Project와 같은 대형 Sequencing 프로젝트와 High-throughput Sequencing 기술의 발전으로 현재 Expressed Sequence Tag (EST)와 같은 대량의 DNA 서열들이 생산되고 있다. 이를 효과적이고 효율적으로 분석해야 할 필요성이 증대되고 있다. 대부분의 실험자들이 서열 분석을 위해 우선적으로 BLAST 검색을 이용하고 있다. 하지만 대량의 서열, 검색 DB의 크기, BLAST 검색 결과의 복잡성에 의해 어려움을 겪고 있다. 이에 빠르고 정리된 결과를 보여줄 수 있는 BLAST 검색 시스템의 필요성이 커지고 있다. 이에 본 논문은 미국 생명공학연구소(NCBI)에서 제공하는 유전자 서열 검색 툴인 BLAST(Basic Logical Alignment Tool)를 클러스터 수퍼 컴퓨터 구축 기술을 기반으로 한 병렬처리와 Gene Ontology를 이용하여 방대한 양의 서열 검색 결과를 요약하는 모형을 제시한다. 이것은 신약개발 및 유전자 발굴 등의 연구기간을 획기적으로 단축시켜 신약 개 발, 농업, 화학, 의료, 환경 등 생명공학 연구에 핵심적인 역할을 할 수 있다. 또한 성능 실험을 통하여 분석결과 대기시간을 최소화하는 병렬처리모형의 효율성을 검증하였다.

• Molecules and Cells
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• v.45 no.2
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• pp.76-83
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• 2022

Neurons-on-a-Chip technology has been developed to provide diverse in vitro neuro-tools to study neuritogenesis, synaptogensis, axon guidance, and network dynamics. The two core enabling technologies are soft-lithography and microelectrode array technology. Soft lithography technology made it possible to fabricate microstamps and microfluidic channel devices with a simple replica molding method in a biological laboratory and innovatively reduced the turn-around time from assay design to chip fabrication, facilitating various experimental designs. To control nerve cell behaviors at the single cell level via chemical cues, surface biofunctionalization methods and micropatterning techniques were developed. Microelectrode chip technology, which provides a functional readout by measuring the electrophysiological signals from individual neurons, has become a popular platform to investigate neural information processing in networks. Due to these key advances, it is possible to study the relationship between the network structure and functions, and they have opened a new era of neurobiology and will become standard tools in the near future.

• Journal of KIISE:Databases
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• v.35 no.2
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• pp.132-142
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• 2008

In biological domain, there exist a variety of protein analysis databases which have their own meaning toward the same target of protein. If we integrate these scattered heterogeneous data efficiently, we can obtain useful information which otherwise cannot be found from each original source. Reflecting the characteristics of biological data, each data source has its own syntax and semantics. If we describe these data through RDF(S) models, one of the Semantic Web standards, we can achieve not only syntactic but also semantic integration. In this paper, we propose a new concept of integration layer based on the RDF unified schema. As a conceptual model, we construct a unified schema focusing on the protein information; as a representational model, we propose a technique for the wrappers to aggregate necessary information from the relevant sources and dynamically generate RDF instances. Two example queries show that our integration layer succeeds in processing the integrated requests from users and displaying the appropriate results.

• Korean Journal of Biological Psychiatry
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• v.11 no.2
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• pp.155-164
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• 2004

Objective:The present study examined the association between basic neurocognitive functions and emotional recognition in chronic schizophrenia. Furthermore, to Investigate cognitive variable related to emotion recognition in Schizophrenia. Methods:Forty eight patients from the Yongin Psychiatric Rehabilitation Center were evaluated for neurocognitive function, and Emotional Recognition Test which has four subscales finding emotional clue, discriminating emotions, understanding emotional context and emotional capacity. Measures of neurocognitive functioning were selected based on hypothesized relationships to perception of emotion. These measures included:1) Letter Number Sequencing Test, a measure of working memory;2) Word Fluency and Block Design, a measure of executive function;3) Hopkins Verbal Learning Test-Korean version, a measure of verbal memory;4) Digit Span, a measure of immediate memory;5) Span of Apprehension Task, a measure of early visual processing, visual scanning;6) Continuous Performance Test, a measure of sustained attention functioning. Correlation analyses between specific neurocognitive measures and emotional recognition test were made. To examine the degree to which neurocognitive performance predicting emotional recognition, hierarchical regression analyses were also made. Results:Working memory, and verbal memory were closely related with emotional discrimination. Working memory, Span of Apprehension and Digit Span were closely related with contextual recognition. Among cognitive measures, Span of Apprehension, Working memory, Digit Span were most important variables in predicting emotional capacity. Conclusion:These results are relevant considering that emotional information processing depends, in part, on the abilities to scan the context and to use immediate working memory. These results indicated that mul- tifaceted cognitive training program added with Emotional Recognition Task(Cognitive Behavioral Rehabilitation Therapy added with Emotional Management Program) are promising.

• Journal of the Korean Society of Food Culture
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• v.30 no.2
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• pp.241-248
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• 2015

The purpose of this study was to investigate the perception of health functional foods and preference for desired onion peel products. Questionnaires were distributed to 582 adults (34.2% male, 65.8% female) living in Gyeongnam province. The major information sources on biological effects of onions cited by respondents were TV/radio (37.1%), followed by nearby people (32.8%) and Internet (11.0%), in that order. Reducing cholesterol effect was the most important factor in terms of perception and concerns relating to biological function of onions. Over 73% of subjects had experience of eating processed onion products, and among all types of onion products, onion juice (53.5%) was the most frequently eaten. The most considered factors for processing onion peel-derived functional foods were taste & odor (29.6%), convenience of eating (28.9%), and nutrition value (27.1%), in that order.