• 제목/요약/키워드: Bio-Sensing

검색결과 217건 처리시간 0.03초

Back-gate bias를 이용한 SOI nano-wire BioFET의 electrical sensing (Electrical sensing of SOI nano-wire BioFET by using back-gate bias)

  • 정명호;안창근;조원주
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.354-355
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    • 2008
  • The sensitivity and sensing margin of SOI(silicon on insulator) nano-wire BioFET(field effect transistor) were investigated by using back-gate bias. The channel conductance modulation was affected by doping concentration, channel length and channel width. In order to obtain high sensitivity and large sensing margin, low doping concentration, long channel and narrow width are required. We confirmed that the electrical sensing by back-gate bias is effective method for evaluation and optimization of bio-sensor.

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소산파의 복굴절을 이용한 광 도파관 센서 (Optical waveguide sensors using optical birefringence of evanescent fields)

  • Son, K.S.;Lee, H.Y.;Kim, W.K.;Lee, S.S.;Park, S.S.;Kwon, S.W.;Lee, E.C.;Park, J.W.;Ju, H.
    • 한국광학회:학술대회논문집
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    • 한국광학회 2008년도 하계학술발표회 논문집
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    • pp.309-310
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    • 2008
  • Polymer optical waveguides are fabricated with high-index materials deposited to strengthen exciations of evanescent field whose birefringence is utilized for optical sensing. Optical sensing properties are examined as a function of time, using different types of analyte solutions to extract noise-free signal induced by evanescent field birefringence. It is observed that sensing signal can be free of initial noise that may obscure real signal recognition, when glycerol is used for sensing characterization, due to slow accumulation process following adsorption of analyte material onto the sensing surface of the waveguide.

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Molecular Basis of Hexanoic Acid Taste in Drosophila melanogaster

  • Roshani Nhuchhen Pradhan;Bhanu Shrestha;Youngseok Lee
    • Molecules and Cells
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    • 제46권7호
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    • pp.451-460
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    • 2023
  • Animals generally prefer nutrients and avoid toxic and harmful chemicals. Recent behavioral and physiological studies have identified that sweet-sensing gustatory receptor neurons (GRNs) in Drosophila melanogaster mediate appetitive behaviors toward fatty acids. Sweet-sensing GRN activation requires the function of the ionotropic receptors IR25a, IR56d, and IR76b, as well as the gustatory receptor GR64e. However, we reveal that hexanoic acid (HA) is toxic rather than nutritious to D. melanogaster. HA is one of the major components of the fruit Morinda citrifolia (noni). Thus, we analyzed the gustatory responses to one of major noni fatty acids, HA, via electrophysiology and proboscis extension response (PER) assay. Electrophysiological tests show this is reminiscent of arginine-mediated neuronal responses. Here, we determined that a low concentration of HA induced attraction, which was mediated by sweet-sensing GRNs, and a high concentration of HA induced aversion, which was mediated by bitter-sensing GRNs. We also demonstrated that a low concentration of HA elicits attraction mainly mediated by GR64d and IR56d expressed by sweet-sensing GRNs, but a high concentration of HA activates three gustatory receptors (GR32a, GR33a, and GR66a) expressed by bitter-sensing GRNs. The mechanism of sensing HA is biphasic in a dose dependent manner. Furthermore, HA inhibit sugar-mediated activation like other bitter compounds. Taken together, we discovered a binary HA-sensing mechanism that may be evolutionarily meaningful in the foraging niche of insects.

Wireless Bio-Signal Sensing System Using a Circular Polarized Antenna

  • Kwon Young-Bae;Park Jung-Min;Choe Jung-Hwan;Park Seong-Ook;Ishida Osami
    • Journal of electromagnetic engineering and science
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    • 제5권3호
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    • pp.132-139
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    • 2005
  • Wireless bio-signal sensing system, which is based on the principle of Doppler radar, can measure a respiration and heart rates with a periodic movement of skin and muscle near the heart. Though the sensing monostatic system using a circulator has been studied, this bistatic system can be improved by using a circular polarized antenna which has a high isolation between transmitter and receiver. In this paper, we measured the bio-signal without the direct contact with the person. The design of each system and experimental results are discussed.

RF 통신을 이용한 동물 생체정보 센싱 시스템 개발 (Implementation of Bio-information Sensing System using RF Communication)

  • 서용배;정중수
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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    • pp.1180-1185
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    • 2009
  • 정보 콘텐츠 기술의 발달로 인하여 모든 정보들이 데이터베이스화 되어가고 있다. 하지만 아직 가축의 생체정보의 데이터베이스 구축은 생체정보의 수집단계의 어려움으로 그 발전이 미약하다. 본 논문은 젖소의 생체정보를 수집 관리하기 위하여 지그비 RF(Radio frequency)통신을 이용한 가축의 생체정보의 수집을 통해 젖소들의 생체상태를 센싱 할 수 있는 시스템을 개발하였고 이를 데이터베이스 구축에 활용하기 위한 논문이다. 센싱 시스템은 8Bit 마이크로 컨트롤러와 기울기센서, 온도센서, RF 모듈로 구성되었다.

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공진 기반 마이크로기계 생화학 센싱 구조물의 해석 (Analysis of Resonance Based Micromechanical Bio-Chemical Sensing Structures)

  • 여민구;신윤혁;임홍재;임시형
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.1767-1772
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    • 2008
  • A microcantilever is a well-known MEMS structure for sensing bio-chemical molecules. When bio-chemical molecules are adsorbed on the microcantilever's surface, resonance frequency shift is generated. There are two issues in this phenomena. The first one is which one between mass change and surface stress change effects is more dominant on the resonance frequency shift. The second one is what will be the performance change when the boundary condition is changed from cantilevers to double clamped beams. We have studied the effect of surface stress change and compared it with that of mass change by using FEM analysis. Furthermore, for microstructures having different boundary conditions, we have studied Q-factor, which determines the detection limit of micro/nano mechanical sensors.

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Characterization of carbon dioxide sensitive fluorescence dye immobilized on the sol-gel

  • Sohn, Ok-Jae;Lam, Tuan-Hung;Rhee, Jong-Il
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2005년도 생물공학의 동향(XVI)
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    • pp.478-481
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    • 2005
  • In this study optical sensing membrane was developed for the queantification of dissolved carbon dioxide in micro-bioreactor using an immobilized 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS). For the immobilization of HPTS sol-gel was synthesied by using 3-glycidoxypropyl-dimethoxymethylsiline and tetraethyl orthosilicate.

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