• Title/Summary/Keyword: Biological Signals

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Regulation of Salicylic Acid and N-Hydroxy-Pipecolic Acid in Systemic Acquired Resistance

  • Gah-Hyun, Lim
    • The Plant Pathology Journal
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    • v.39 no.1
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    • pp.21-27
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    • 2023
  • In plants, salicylic acid (SA) is a central immune signal that is involved in both local and systemic acquired resistance (SAR). In addition to SA, several other chemical signals are also involved in SAR and these include N-hydroxy-pipecolic acid (NHP), a newly discovered plant metabolite that plays a crucial role in SAR. Recent discoveries have led to a better understanding of the biosynthesis of SA and NHP and their signaling during plant defense responses. Here, I review the recent progress in role of SA and NHP in SAR. In addition, I discuss how these signals cooperate with other SAR-inducing chemicals to regulate SAR.

Understanding of the Working Principle of Field-effect Transistor (FET) Biosensor with the Review Of Experimental Measurement Set-up (전계효과트랜지스터(FET) 바이오센서 실험 셋업 분석을 통한 동작원리 이해)

  • Kook-Nyung Lee
    • Journal of Sensor Science and Technology
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    • v.32 no.6
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    • pp.487-495
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    • 2023
  • Over the past few decades, considerable research has been conducted on field-effect transistor (FET) biosensors; however, other than electrochemical sensors for pH, they have not reached the commercialization stage and still remain at the basic research level. Although several reports have been published on experiments with real biological samples, no reports exist of developments that have reached commercialization or finalized approval for use. In this paper, we explain the reason for the experiments of FET biosensors to induce spurious signals in an experimental setup and explain the existence of misunderstandings regarding the operating principle of FET biosensors owing to the spurious signals. Based on the thoughtful review of the results of previously published papers, we show that the electrochemical read-out principle of FET biosensors requires our intensive understanding of the interfacial potential between the solution and the sensor electrode for further progress in the FET biosensor research.

A Quantitative Analysis of Electromyography Obtained from Subjects Performing Seated Tasks (앉은 자세로 행하는 작업에서 측정된 근전도의 정량적 해석)

  • Son, Kwon
    • Journal of Biomedical Engineering Research
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    • v.13 no.1
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    • pp.9-18
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    • 1992
  • This paper describes a quantitative analysis of electromyography (EMG) measured from seven subjects performing four seated dynamic tasks. EMG signals were mom- bored using 15 surface electrodes which were placed on selected trunk and lower extrmity muscles of the right side of the body. Each EMG signal was then processed through rectification, integration, and filtering. Based on the maximum level of the processed EMG, it was found that the trunk and ankle muscles play an important role on the postural control during the seated tasks.

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A Study on the Multigate Pulsed Doppler System. (다중 채널 펄스 도플러 장치에 관한 연구)

  • 김병철;박세현
    • Journal of Biomedical Engineering Research
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    • v.7 no.1
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    • pp.75-79
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    • 1986
  • In this paper, a multigate pulsed doppler system with parallel signal processing which enables the transcutaneous assesment of the blood-flow velocities of five adjacent sample volumes is developed. The outputs of the system are audio signals, velocity curves and velocity profiles of 5 adjacent sample volumes. We have applied to the major superficial arteries and obtained the detailed information about the time dependent blood-flow behavior.

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Rejection of Impulsive Noise and Baseline Wandering Using Morphological Operators (형태연산자를 이용한 심전도신호에 있어서의 임펄시브 노이즈와 기저선의 흔들림의 제거)

  • Kim, Chang-Jae;Nam, Seung-Woo;Shin, Gun-Soo;Lee, Myoung-Ho
    • Proceedings of the KOSOMBE Conference
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    • v.1990 no.11
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    • pp.110-113
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    • 1990
  • A new approach to impulsive noise rejection and background normalization of digitized electrocardiogram signals is presented using mathematical morphological operators that incoporate the shape information of a signal. A brief introduction to these nonlinear signal processing operators, as well as detailed description of the new algorithm, is presented. Empirical results show that the new algorithm has good performance in impulsive noise rejection and background normalization.

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Battery Power Switching System for Implantable Telemetry Systems (체내 삽입 텔리메터리 시스템용 전원 스위칭 시스템 개발)

  • Seo, Hee-Don
    • Proceedings of the KOSOMBE Conference
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    • v.1990 no.11
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    • pp.118-121
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    • 1990
  • This paper describes development of an implantable power switching system for biotelemetry system. This system is designed and manufactured to achieve as small size and low power dissipation as possible, using pulse powered circult and CMOS technology. The function of the power switching system is to connect the implantable battery to implanted sensors and, electronics systems by receiving intermittent command signals from external circuits. The power dissipation of this system was about $15{\mu}W$ for a stand-by operation.

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Double clad fiber probe for fluorescence spectroscopy

  • Wang, Ling;Lee, Byeong-Ha
    • Proceedings of the Optical Society of Korea Conference
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    • 2007.07a
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    • pp.35-36
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    • 2007
  • We report a probe using a single double clad fiber (DCF) for fluorescence spectroscopy. Bidirectional separate transmission for excitation and fluorescence light in a single fiber was implemented. A DCF coupler made by side-polished method could extract none but the collected fluorescence signals propagating in inner cladding mode, thereby diminishing the interference of silica background generated by the excitation in core mode. The experimental results show that the fluorescence spectra of biological tissues obtained using the DCF probes have much less silica background than using a standard multiple-mode fiber.

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A Study on the Development of CW(Continuous-Wave)Doppler System for measuring Bi-directional Blood Flow Information (혈류 방향을 구별하는 연속 초음파 도플러 장치에 관한 연구)

  • 강충신;김영길
    • Journal of Biomedical Engineering Research
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    • v.8 no.1
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    • pp.75-80
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    • 1987
  • With the conventional CW Doppler velocity meter, bl-directional velocities cannot be separated. The new CW Doppler system uses quadrature detection and phase rotation to produce simultaneous independent audio and velocity signals for forward and reverse blood flow direction, is fabricated. Specially, this system shows that phase rotation method for flow direction separation provides easy and satisfactory feature. From in vivo blood flow measurement, we can easily differentiate typical artery flow from vein flow, and measure both velocity characteristics qualitatively.

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Fundamental study for the restoration of the body movement by Functional Electrical Stimulation (FES) - EMG Analysis of the rolling-over motion -

  • Murakami, H.;Ohba, S.;Futami, R.;Hoshimiya, N.;Handa, Y.
    • Proceedings of the KOSOMBE Conference
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    • v.1991 no.11
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    • pp.88-89
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    • 1991
  • A method in order to restore the body movement by means of Functional Electrical Stimulation (FES) was considered. Multichannel EMG signals from a normal subject during the rolling-over motion were measured and analyzed. The results of the experiment indicated the synergetic role of the muscles during the desired motion.

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Topographic Brain Map of Multi-Channel EEG by Spectrum Analysis Method (스펙트럼 해석방법에 의한 다중찬넬 뇌파의 Topographic Brain Map)

  • 유선국;고한우
    • Journal of Biomedical Engineering Research
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    • v.9 no.1
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    • pp.31-36
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    • 1988
  • A personal computer-based brain map is described which will display a gray scale maps showing the distribution of signals derived from the electrical activity of the brain such as EEG or EP This topographic brain mapping system has a flexibility which describe the electrode number and placement mapping onto any shaped space and generate a brain maps by incoorporated the data acquisition and processing software with conventional EEG machine.

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