• 제목/요약/키워드: Biological Signal

검색결과 1,262건 처리시간 0.025초

Conformational Change of Escherichia coli Signal Recognition Particle Ffh Is Affected by the Functionality of Signal Peptides of Ribose-Binding Protein

  • Ahn, Taeho;Ko, Ju Hee;Cho, Eun Yi;Yun, Chul-Ho
    • Molecules and Cells
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    • 제27권6호
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    • pp.681-687
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    • 2009
  • We examined the effects of synthetic signal peptides, wild-type (WT) and export-defective mutant (MT) of ribose-binding protein, on the conformational changes of signal recognition particle 54 homologue (Ffh) in Escherichia coli. Upon interaction of Ffh with WT peptide, the intrinsic Tyr fluorescence, the transition temperature of thermal unfolding, and the GTPase activity of Ffh decreased in a peptide concentration-dependent manner, while the emission intensity of 8-anilinonaphthalene-1-sulfonic acid increased. In contrast, the secondary structure of the protein was not affected. Additionally, polarization of fluorescein-labeled WT increased upon association with Ffh. These results suggest that WT peptide induces the unfolded states of Ffh. The WT-mediated conformational change of Ffh was also revealed to be important in the interaction between SecA and Ffh. However, MT had marginal effect on these conformational changes suggesting that the in vivo functionality of signal peptide is important in the interaction with Ffh and concomitant structural change of the protein.

멀티레이터 샘플링 문제로서의 뇌파신호 디스플레이에 관한 연구 (The Study of EEG Signal Display as a Multirate Sampling Problem)

  • 최한고
    • 대한의용생체공학회:의공학회지
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    • 제17권2호
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    • pp.209-214
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    • 1996
  • The display of biological signals in raster scan monitors often involves a multirate sampling operation which consists of decimation .and interpolation. All electroencephalouaphic (EEG) samples of 10 to 30 seconds (2, 500 to 7, 500 samples at 250[Hz] sampling frequency) must be displayed in the computer screen to keep the aspect ratio of the paper polygraph output. Since the current afrorclable display technology Plots at most 2, 000 Pixels Per row, sDme signal samples need to be discarde4 This Paper studies methods to perform this operation characterizing them from the signal processing viewpoint and compares the display quality among several decimation techniques. Experimental results show that a nonlinear operation such as the peak detection method could be preferable to the canonical linear filtering to reduce aliasing.

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고품질 멀티미디어 기반 응급 원격 진료서비스를 위한 생체신호 무손실 압축, 복원 프로그램 개발 (Development of the Lossless Biological Signal Compression Program for High-quality Multimedia based Real-Time Emergency Telemedicine Service)

  • 임영호;김정상;윤태성;유선국
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 D
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    • pp.2727-2729
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    • 2002
  • In an emergency telemedicine system such as High-quality Multimedia based Real-time Emergency Telemedicine(HMRET) service, it is very important to examine the status of the patient continuously using the multimedia data including the biological signals(ECG, BP, Respiration, $SpO_2$) of the patient. In order to transmit these data real time through the communication means which have the limited transmission capacity. It is also necessary to compress the biological data besides other multimedia data. For the HMRET service, we developed the lossless biological signal compression program in MSVC++ 6.0 using DPCM method and JPEG Huffman table, and tested in an internet environment.

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EMG 신호의 기능 분류에 적용되는 CEPSTRUM 기법에 관한 연구 (A Study on the CEPSTRUM Method for the Function Classification of EMG Signal)

  • 왕문성;변윤식;박상희
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1992년도 추계학술대회
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    • pp.79-82
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    • 1992
  • Under the assumption that the EMG signal was used as the reference signal for driving a prosthetic arm, function discrimination of EMG signal from the biceps and triceps of subject was achived with LPC CEPSTRUM coefficients. By varying the number of coefficients, the types of windows, window size, and window overlaping rates, the best conditions for the function discrimination of EMG signal were obtained.

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생체 카오스의 비선형 시계열 데이터 분석 (Nonlinear Time Series Analysis of Biological Chaos)

  • 이병채;이명호
    • 대한의용생체공학회:의공학회지
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    • 제15권3호
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    • pp.347-354
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    • 1994
  • This paper describes a diagnostic protocol of nonlinear dynamic characteristics of biological system using chaos theory. An integrated chaos analysis system for the diagnosis of biological system was designed. We suggest a procedure of attractor reconstruction for reliable qualitative and quantitative analysis. The effect of autonomic nervous system activity on heart rate variability with power spectral analysis and its characteristics of chaotic attractors are investigated. The results show the applicability to evaluate the mental and physical conditions using nonlinear characteristics of biological signal.

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Cloning, Sequencing and Baculovirus-based Expression of Fusion-Glycoprotein D Gene of Herpes Simplex Virus Type 1 (F)

  • Uh, Hong-Sun;Choi, Jin-Hee;Byun, Si-Myung;Kim, Soo-Young;Lee, Hyung-Hoan
    • BMB Reports
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    • 제34권4호
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    • pp.371-378
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    • 2001
  • The Glycoprotein D (gD) gene of the HSV-1 strain F was cloned, sequenced, recombinated into the HcNPV (Hyphantria cunea nuclear polyhedrosis virus) expression vector and expressed in insect cells. The gD gene was located in the 6.43 kb BamHI fragment of the strainF. The open reading frame (ORF) of the gD gene was 1,185 by and codes 394 amino acid residues. Recombinant baculoviruses, GD-HcNPVs, expressing the gD protein were constructed. Spodoptera frugiperda cells, infected with the recombinant virus, synthesized a matured gX-gD fusion protein with an approximate molecular weight of 54 kDa and secreted the gD proteins into the culture media by an immunoprecipitation assay The fusion gD protein was localized on the membrane of the insect cells, seen by using an immunofluorescence assay The deduced amino acid sequence presents additional characteristics compatible with the structure of a viral glycoprotein: signal peptide, putative glycosylation sites and a long C-terminal transmembrane sequence. These results indicate the utility of the HcNPV-insect cell system for producing and characterizing eukaryotic proteins.

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Surface-enhanced infrared detection of benzene in air using a porous metal-organic-frameworks film

  • Kim, Raekyung;Jee, Seohyeon;Ryu, Unjin;Lee, Hyeon Shin;Kim, Se Yun;Choi, Kyung Min
    • Korean Journal of Chemical Engineering
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    • 제36권6호
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    • pp.975-980
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    • 2019
  • Infrared (IR) spectroscopy is a powerful technique for observing organic molecules, as it combines sensitive vibrational excitations with a non-destructive probe. However, gaseous volatile compounds in the air are challenging to detect, as they are not easy to immobilize in a sensing device and give enough signal by themselves. In this study, we fabricated a thin nanocrystalline metal-organic framework (nMOF) film on a surface plasmon resonance (SPR) substrate to enhance the IR vibration signal of the gaseous volatile compounds captured within the nMOF pores. Specifically, we synthesized nanocrystalline HKUST-1 (nHKUST-1) particles of ca. 80 nm diameter and used a colloidal dispersion of these particles to fabricate nHKUST-1 films by a spin-coating process. After finding that benzene was readily adsorbed onto nHKUST-1, an nHKUST-1 film deposited on a plasmonic Au substrate was successfully applied to the IR detection of gaseous benzene in air using surface-enhanced IR spectroscopy.