21 research outputs found

    Wavelet Transform for Real-Time Detection of Action Potentials in Neural Signals

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    We present a study on wavelet detection methods of neuronal action potentials (APs). Our final goal is to implement the selected algorithms on custom integrated electronics for on-line processing of neural signals; therefore we take real-time computing as a hard specification and silicon area as a price to pay. Using simulated neural signals including APs, we characterize an efficient wavelet method for AP extraction by evaluating its detection rate and its implementation cost. We compare software implementation for three methods: adaptive threshold, discrete wavelet transform (DWT), and stationary wavelet transform (SWT). We evaluate detection rate and implementation cost for detection functions dynamically comparing a signal with an adaptive threshold proportional to its SD, where the signal is the raw neural signal, respectively: (i) non-processed; (ii) processed by a DWT; (iii) processed by a SWT. We also use different mother wavelets and test different data formats to set an optimal compromise between accuracy and silicon cost. Detection accuracy is evaluated together with false negative and false positive detections. Simulation results show that for on-line AP detection implemented on a configurable digital integrated circuit, APs underneath the noise level can be detected using SWT with a well-selected mother wavelet, combined to an adaptive threshold

    Méthodes et systÚmes pour la détection adaptative et temps réel d'activité dans les signaux biologiques

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    L intéraction entre la biologie et l électronique est une discpline en pleine essort. De nom-breux systÚmes électroniques tentent de s interconnecter avec des tissus ou des cellules vivantesa n de décoder l information biologique. Le Potentiel d action (PA) est au coeur de codagebiologique et par conséquent il est nécéssaire de pouvoir les repérer sur tout type de signal bio-logique. Par conséquent, nous étudions dans ce manuscrit la possibilité de concevoir un circuitélectronique couplé à un systÚme de microélectrodes capable d e ectuer une acquisition, unedétection des PAs et un enregistrement des signaux biologiques. Que ce soit en milieu bruitéou non, nous considérons le taux de détection de PA et la contrainte de temps réel commedes notions primordiales et la consommation en silicium comme un prix à payer. Initialementdéveloppés pour l étude de signaux neuronaux et pancréatiques, ces systÚmes conviennent par-faitement pour d autres type de cellules.Interaction between biology and electronic is in expansion. Many electronic systems aretrying to interconnect with tissues or living cells to decode biological information. The ActionPotential (AP) is the heart of biological coding and therefore it is necessary to be able to locateit from any type of biological signal. Therefore, we study in this manuscript the possibility ofdesigning an electronic circuit coupled to microelectrodes capable of acquisition, detection ofPAs and recording of biological signals. Whether or not in a noisy environment, we consider thedetection rate of PA and the real time-computing constraint as an hard speci cationand andsilicon area as a price to pay. Initially developed for the study of neural signals and pancreatic,these systems are ideal for other types of cells.BORDEAUX1-Bib.electronique (335229901) / SudocSudocFranceF

    Systems and methods for adaptive and real-time detection of biological activity

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    L’intĂ©raction entre la biologie et l’électronique est une discpline en pleine essort. De nom-breux systĂšmes Ă©lectroniques tentent de s’interconnecter avec des tissus ou des cellules vivantesaïŹn de dĂ©coder l’information biologique. Le Potentiel d’action (PA) est au coeur de codagebiologique et par consĂ©quent il est nĂ©cĂ©ssaire de pouvoir les repĂ©rer sur tout type de signal bio-logique. Par consĂ©quent, nous Ă©tudions dans ce manuscrit la possibilitĂ© de concevoir un circuitĂ©lectronique couplĂ© Ă  un systĂšme de microĂ©lectrodes capable d’eïŹ€ectuer une acquisition, unedĂ©tection des PAs et un enregistrement des signaux biologiques. Que ce soit en milieu bruitĂ©ou non, nous considĂ©rons le taux de dĂ©tection de PA et la contrainte de temps rĂ©el commedes notions primordiales et la consommation en silicium comme un prix Ă  payer. InitialementdĂ©veloppĂ©s pour l’étude de signaux neuronaux et pancrĂ©atiques, ces systĂšmes conviennent par-faitement pour d’autres type de cellules.Interaction between biology and electronic is in expansion. Many electronic systems aretrying to interconnect with tissues or living cells to decode biological information. The ActionPotential (AP) is the heart of biological coding and therefore it is necessary to be able to locateit from any type of biological signal. Therefore, we study in this manuscript the possibility ofdesigning an electronic circuit coupled to microelectrodes capable of acquisition, detection ofPAs and recording of biological signals. Whether or not in a noisy environment, we consider thedetection rate of PA and the real time-computing constraint as an hard speciïŹcationand andsilicon area as a price to pay. Initially developed for the study of neural signals and pancreatic,these systems are ideal for other types of cells

    Méthodes et systÚmes pour la détection adaptative et temps réel d'activité dans les signaux biologiques

    No full text
    Interaction between biology and electronic is in expansion. Many electronic systems aretrying to interconnect with tissues or living cells to decode biological information. The ActionPotential (AP) is the heart of biological coding and therefore it is necessary to be able to locateit from any type of biological signal. Therefore, we study in this manuscript the possibility ofdesigning an electronic circuit coupled to microelectrodes capable of acquisition, detection ofPAs and recording of biological signals. Whether or not in a noisy environment, we consider thedetection rate of PA and the real time-computing constraint as an hard speci cationand andsilicon area as a price to pay. Initially developed for the study of neural signals and pancreatic,these systems are ideal for other types of cells.L'interaction entre la biologie et l Ă©lectronique est une discipline en pleine essort. De nombreux systĂšmes Ă©lectroniques tentent de s interconnecter avec des tissus ou des cellules vivantes afin de dĂ©coder l information biologique. Le Potentiel d action (PA) est au cƓur de codage biologique et par consĂ©quent il est nĂ©cessaire de pouvoir les repĂ©rer sur tout type de signal bio-logique. Par consĂ©quent, nous Ă©tudions dans ce manuscrit la possibilitĂ© de concevoir un circuit Ă©lectronique couplĂ© Ă  un systĂšme de microĂ©lectrodes capable d'effectuer une acquisition, une dĂ©tection des PAs et un enregistrement des signaux biologiques. Que ce soit en milieu bruitĂ© ou non, nous considĂ©rons le taux de dĂ©tection de PA et la contrainte de temps rĂ©el comme des notions primordiales et la consommation en silicium comme un prix Ă  payer. Initialement dĂ©veloppĂ©s pour l Ă©tude de signaux neuronaux et pancrĂ©atiques, ces systĂšmes conviennent parfaitement pour d autres type de cellules

    Systems and methods for adaptive and real-time detection of biological activity

    No full text
    L’intĂ©raction entre la biologie et l’électronique est une discpline en pleine essort. De nom-breux systĂšmes Ă©lectroniques tentent de s’interconnecter avec des tissus ou des cellules vivantesaïŹn de dĂ©coder l’information biologique. Le Potentiel d’action (PA) est au coeur de codagebiologique et par consĂ©quent il est nĂ©cĂ©ssaire de pouvoir les repĂ©rer sur tout type de signal bio-logique. Par consĂ©quent, nous Ă©tudions dans ce manuscrit la possibilitĂ© de concevoir un circuitĂ©lectronique couplĂ© Ă  un systĂšme de microĂ©lectrodes capable d’eïŹ€ectuer une acquisition, unedĂ©tection des PAs et un enregistrement des signaux biologiques. Que ce soit en milieu bruitĂ©ou non, nous considĂ©rons le taux de dĂ©tection de PA et la contrainte de temps rĂ©el commedes notions primordiales et la consommation en silicium comme un prix Ă  payer. InitialementdĂ©veloppĂ©s pour l’étude de signaux neuronaux et pancrĂ©atiques, ces systĂšmes conviennent par-faitement pour d’autres type de cellules.Interaction between biology and electronic is in expansion. Many electronic systems aretrying to interconnect with tissues or living cells to decode biological information. The ActionPotential (AP) is the heart of biological coding and therefore it is necessary to be able to locateit from any type of biological signal. Therefore, we study in this manuscript the possibility ofdesigning an electronic circuit coupled to microelectrodes capable of acquisition, detection ofPAs and recording of biological signals. Whether or not in a noisy environment, we consider thedetection rate of PA and the real time-computing constraint as an hard speciïŹcationand andsilicon area as a price to pay. Initially developed for the study of neural signals and pancreatic,these systems are ideal for other types of cells

    Optical Feedback Interferometry sensor for flow characterization inside ex-vivo vessel

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    International audience—Pressure myograph systems allow the study of pharmacological effects of drugs and other vasoactive compounds on small isolated vessels by image processing. In this work, we present a new pressure myograph system based on Optical Feedback Interferometry (OFI) sensor that gives information about local velocity in fluids and enables reconstruction of a velocity profile inside a vessel. OFI is a self-aligned interferometric technique that uses the laser as both the light source and the receiver thus offering high sensitivity, fast response, and a simple and compact optical design. The local Doppler flow velocity is directly measured inside ex-vivo rat vessel with a step of 100 ”m thus avoiding the need to use complex image processing and models based profile calculation for extracting flow velocity. This technique will be useful to investigate hemodynamics in microcirculation by measuring unsteady irregular blood

    In-situ measurement of non-steady flows using optical feedback interferometry

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    International audienceWe present a real-time system for flow measurement in millifluidic configuration based on optical feedback interfero-metry. The sensing method exploits the power spectral density information of the acquired signals affected by the backscattered light of particles contained in a fluid. We validate experimentally the method on-site by reconstructing the periodicity of non-steady flows of a peristaltic pump. This demonstrates potential applications for flow assessments in closed liquid-filled circuits

    Profiling oil-water flows in microchannel: preliminary results using Optical Feedback Interferometry

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    International audienceWe study oil-water flows in a Y-shaped rectangular cross-section microreactor with different parameters at each inlet. A theoretical model based on a Couette flow approximation is proposed and Navier-Stokes equation is solved for the relative movement in between oil and water plates. The model is further validated with preliminary measurements for flow profile reconstruction using optical feedback interferometry. The proposed method shows potential applications in assessment of immiscible flowing fluid
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