scholarly journals Simple and low-cost amplifier system for the study of a ventral nerve action potential in earthworm

2019 ◽  
Author(s):  
Orlando Jorquera
Keyword(s):  
Action Potential ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Experimental System ◽  
Lumbricus Terrestris ◽  
Simulation Software ◽  
High Signal ◽  
Giant Fiber ◽  
Basic Principles ◽  
Met Expectations

AbstractBasic Biophysics or Neurobiology courses encounter problems when starting their practices due to the complexity and high cost of the equipment. As a consequence, these experiences are replaced by simulation software, leading students to boredom and disinterest, and finally to the lack of understanding of the basic principles of the phenomenon observed. Classical nerve conduction studies for the visualization of action potentials are an example of this, being able to be developed with simple and low-cost amplification circuits, as described in this article. The system showed stability, expected amplification and high signal-to-noise ratio. The action potential of the medial giant fiber (MGF) as lateral giant fiber (LGF) in the ventral nerve cord of the earthworms Lumbricus terrestris was recorded. The experimental system has met expectations and regains practical, effective and stimulating learning for students.

scholarly journals Wind Turbine Noise Reduction from Seismological Data

2021 ◽  
Author(s):  
Janis Heuel ◽  
Wolfgang Friederich
Keyword(s):  
Signal To Noise Ratio ◽  
Low Cost ◽  
Computational Cost ◽  
Noise Signal ◽  
Noise Model ◽  
Threshold Function ◽  
High Signal ◽  
Time Data ◽  
Negative Effects ◽  
Before And After

<p>Over the last years, installations of wind turbines (WTs) increased worldwide. Owing to<br>negative effects on humans, WTs are often installed in areas with low population density.<br>Because of low anthropogenic noise, these areas are also well suited for sites of<br>seismological stations. As a consequence, WTs are often installed in the same areas as<br>seismological stations. By comparing the noise in recorded data before and after<br>installation of WTs, seismologists noticed a substantial worsening of station quality leading<br>to conflicts between the operators of WTs and earthquake services.</p><p>In this study, we compare different techniques to reduce or eliminate the disturbing signal<br>from WTs at seismological stations. For this purpose, we selected a seismological station<br>that shows a significant correlation between the power spectral density and the hourly<br>windspeed measurements. Usually, spectral filtering is used to suppress noise in seismic<br>data processing. However, this approach is not effective when noise and signal have<br>overlapping frequency bands which is the case for WT noise. As a first method, we applied<br>the continuous wavelet transform (CWT) on our data to obtain a time-scale representation.<br>From this representation, we estimated a noise threshold function (Langston & Mousavi,<br>2019) either from noise before the theoretical P-arrival (pre-noise) or using a noise signal<br>from the past with similar ground velocity conditions at the surrounding WTs. Therefore, we<br>installed low cost seismometers at the surrounding WTs to find similar signals at each WT.<br>From these similar signals, we obtain a noise model at the seismological station, which is<br>used to estimate the threshold function. As a second method, we used a denoising<br>autoencoder (DAE) that learns mapping functions to distinguish between noise and signal<br>(Zhu et al., 2019).</p><p>In our tests, the threshold function performs well when the event is visible in the raw or<br>spectral filtered data, but it fails when WT noise dominates and the event is hidden. In<br>these cases, the DAE removes the WT noise from the data. However, the DAE must be<br>trained with typical noise samples and high signal-to-noise ratio events to distinguish<br>between signal and interfering noise. Using the threshold function and pre-noise can be<br>applied immediately on real-time data and has a low computational cost. Using a noise<br>model from our prerecorded database at the seismological station does not improve the<br>result and it is more time consuming to find similar ground velocity conditions at the<br>surrounding WTs.</p>

Internally Modulated Chirped Pulse Based Direct Detection Type φ-OTDR System with High Signal-to-Noise Ratio and Low Cost

2019 ◽  
Vol 46 (8) ◽  
pp. 0806003
Author(s):  
李鲁川 Luchuan Li ◽  
卢斌 Bin Lu ◽  
王校 Xiao Wang ◽  
梁嘉靖 Jiajing Liang ◽  
郑汉荣 Hanrong Zheng ◽  
...  
Keyword(s):  
Direct Detection ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
High Signal ◽  
Signal To Noise ◽  
Chirped Pulse ◽  
Noise Ratio

scholarly journals Double-Layer Flexible Neural Probe With Closely Spaced Electrodes for High-Density in vivo Brain Recordings

2021 ◽  
Vol 15 ◽  
Author(s):  
Sara Pimenta ◽  
José A. Rodrigues ◽  
Francisca Machado ◽  
João F. Ribeiro ◽  
Marino J. Maciel ◽  
...  
Keyword(s):  
Double Layer ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
High Signal ◽  
Composition Analysis ◽  
Assessment Tests ◽  
Flexible Polymer ◽  
Mouse Cortex ◽  
Neural Probe

Flexible polymer neural probes are an attractive emerging approach for invasive brain recordings, given that they can minimize the risks of brain damage or glial scaring. However, densely packed electrode sites, which can facilitate neuronal data analysis, are not widely available in flexible probes. Here, we present a new flexible polyimide neural probe, based on standard and low-cost lithography processes, which has 32 closely spaced 10 μm diameter gold electrode sites at two different depths from the probe surface arranged in a matrix, with inter-site distances of only 5 μm. The double-layer design and fabrication approach implemented also provides additional stiffening just sufficient to prevent probe buckling during brain insertion. This approach avoids typical laborious augmentation strategies used to increase flexible probes’ mechanical rigidity while allowing a small brain insertion footprint. Chemical composition analysis and metrology of structural, mechanical, and electrical properties demonstrated the viability of this fabrication approach. Finally, in vivo functional assessment tests in the mouse cortex were performed as well as histological assessment of the insertion footprint, validating the biological applicability of this flexible neural probe for acquiring high quality neuronal recordings with high signal to noise ratio (SNR) and reduced acute trauma.

scholarly journals Particle Imaging Velocimetry Gyroscope

Sensors ◽  
2019 ◽  
Vol 19 (21) ◽  
pp. 4734
Author(s):  
Ahmed A. Youssef ◽  
Naser El-Sheimy
Keyword(s):  
Signal To Noise Ratio ◽  
Low Cost ◽  
Particle Imaging Velocimetry ◽  
High Signal ◽  
Inertial Measurement Units ◽  
Signal To Noise ◽  
Inertial Measurement ◽  
Measurement Units ◽  
Particle Imaging ◽  
Bias Instability

Inertial measurement units (IMUs) are typically classified as per the performance of the gyroscopes within each system. Consequently, it is critical for a system to have a low bias instability to have better performance. Nonetheless, there is no IMU available commercially that does not actually suffer from bias-instability, even for the navigation grade IMUs. This paper introduces the proposition of a novel fluid-based gyroscope, which is referred to hereafter as a particle imaging velocimetry gyroscope (PIVG). The main advantages of the PIVG include being nearly drift-free, a high signal-to-noise ratio (SNR) in comparison to commercially available high-end gyroscopes, and its low cost.

IMPLEMENTATION OF AN INEXPENSIVE AND IMPROVED PURPOSE-BUILT HIGH SNR BIOMEDICAL SIGNAL CAPTURE, RECORD, AND ANALYSIS SYSTEM

2020 ◽  
pp. 2150004
Author(s):  
Tung-Tai Kuo ◽  
Rong-Chin Lo ◽  
Yuan-Hao Chen ◽  
Chung-Ling Tseng
Keyword(s):  
Signal To Noise Ratio ◽  
Low Cost ◽  
High Signal ◽  
Record System ◽  
Brain Wave ◽  
Biomedical Signal ◽  
Accuracy And Precision ◽  
Analysis System ◽  
The Brain ◽  
Brain Study

It is very important for the brain study to design a multi-channel and high signal-to-noise ratio (SNR) bio-medical signal capture, record, and analysis system, which can effectively enhance accuracy and precision of the signal capture under dozens to hundreds of microvolts. Unfortunately, the system for data acquisition is very easily interfered by the environment, the power, and the bio-amplifier, so that the results will lead to a failed promotion of capturing high SNR signals, especially in the tiny brain wave signal. In this study, it has been designed an inexpensive, purpose-built, high SNR brainwave signals measurement system. The system is composed of an improved capture system, record system, and analysis system. To better consider the strength and characteristics of the tiny brainwave signals, the system was designed to include a suitable bio-amplifier to make each channel of the invasive microelectrode able to collect the brainwave signals correctly and it provides recording and analysis software, which can not only extract the characteristics of brainwave signals, but also quickly classify signals. The system can collect biological signals from 10[Formula: see text][Formula: see text]V to 420[Formula: see text][Formula: see text]V and has a high SNR[Formula: see text]30. The proposed system is easy to make and can be fabricated for the relatively low cost of only US$203. The brain wave signals from the three actions can also be easily classified, with a correct rate up to 46.70%. The system has six improvements: good SNR, the ability to capture small signals, modularity, a low price, easy fabrication, and simple operation.

scholarly journals A Solution to Ambiguities in Position Estimation for Solenoid Actuators by Exploiting Eddy Current Variations

Sensors ◽  
2020 ◽  
Vol 20 (12) ◽  
pp. 3441 ◽  
Author(s):  
Niklas König ◽  
Matthias Nienhaus
Keyword(s):  
Eddy Current ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
High Sensitivity ◽  
Position Estimation ◽  
High Signal ◽  
Wide Field ◽  
Fusion Algorithm ◽  
Case Scenario ◽  
Position Detection

Position estimation techniques for solenoid actuators are successfully used in a wide field of applications requiring monitoring functionality without the need for additional sensors. Most techniques, which also include standstill condition, are based on the identification of the differential inductance, a parameter that exhibits high sensitivity towards position variations. The differential inductance of some actuators shows a non-monotonic dependency over the position. This leads to ambiguities in position estimation. Nevertheless, a unique position estimation in standstill condition without prior knowledge of the actuator state is highly desired. In this work, the eddy current losses inside the actuator are identified in terms of a parallel resistor and are exploited in order to solve the ambiguities in position estimation. Compared to other state-of-the-art techniques, the differential inductance and the parallel resistance are estimated online by approaches requiring low implementation and computation effort. Furthermore, a data fusion algorithm for position estimation based on a neural network is proposed. Experimental results involving a use case scenario of an end-position detection for a switching solenoid actuator prove the uniqueness, the precision and the high signal-to-noise ratio of the obtained position estimate. The proposed approach therefore allows the unique estimation of the actuator position including standstill condition suitable for low-cost applications demanding low implementation effort.

scholarly journals Intracellular action potential recordings from cardiomyocytes by ultrafast pulsed laser irradiation of fuzzy graphene microelectrodes

2021 ◽  
Vol 7 (15) ◽  
pp. eabd5175
Author(s):  
Michele Dipalo ◽  
Sahil K. Rastogi ◽  
Laura Matino ◽  
Raghav Garg ◽  
Jacqueline Bliley ◽  
...  
Keyword(s):  
Action Potential ◽  
Action Potentials ◽  
Field Effect Transistors ◽  
Signal To Noise Ratio ◽  
Three Dimensional ◽  
Pulsed Laser ◽  
Extracellular Recording ◽  
High Signal ◽  
Intimate Contact ◽  
Potential Shape

Graphene with its unique electrical properties is a promising candidate for carbon-based biosensors such as microelectrodes and field effect transistors. Recently, graphene biosensors were successfully used for extracellular recording of action potentials in electrogenic cells; however, intracellular recordings remain beyond their current capabilities because of the lack of an efficient cell poration method. Here, we present a microelectrode platform consisting of out-of-plane grown three-dimensional fuzzy graphene (3DFG) that enables recording of intracellular cardiac action potentials with high signal-to-noise ratio. We exploit the generation of hot carriers by ultrafast pulsed laser for porating the cell membrane and creating an intimate contact between the 3DFG electrodes and the intracellular domain. This approach enables us to detect the effects of drugs on the action potential shape of human-derived cardiomyocytes. The 3DFG electrodes combined with laser poration may be used for all-carbon intracellular microelectrode arrays to allow monitoring of the cellular electrophysiological state.

Low-Cost Teleoperation of Remotely Located Actuators Based on Dual Tone Multi-Frequency Data Transfer

2011 ◽  
Vol 403-408 ◽  
pp. 4727-4734
Author(s):  
Sahil Thakkar ◽  
Animesh Garg ◽  
Adesh Midha ◽  
Prerna Gaur
Keyword(s):  
Cell Phone ◽  
Data Transfer ◽  
Signal To Noise Ratio ◽  
High Reliability ◽  
Low Cost ◽  
Control Unit ◽  
Industrial Applications ◽  
High Signal ◽  
Voice Call ◽  
Car Security

DTMF (Dual Tone Multi Frequency) is a system of signal tones used for telecommunications. DTMF uses two tones to represent each key on the touch pad. DTMF data transfer technique has advantages such as high reliability, constant speed, and high signal to noise ratio, low cost and optimal utilization of existing resources. These features make DTMF an attractive Data Transfer Technique. It finds application in home and car security systems, robot control, SMS and voice call controlled industrial applications. In this paper, we discuss the use of DTMF data transfer in a voice call to control a toy car. Cell phone 1(CP 1), which is at user end, makes a call to cell phone 2(CP 2) at the machine end and establishes a connection. A key is pressed at the user side. Two tones corresponding to one key are encoded and sent through the cell phone network. Both tones are tapped through the earphone jack of cell phone at machine end and are decoded. The output is fed to a Micro-controller. The Micro-controller is connected to the remote control unit of the toy car, which in turn controls the motion of the car. The car moves in various directions according to the key pressed user. The electronic circuit is divided into 2 parts. The transmitter side consisting of Cell phone 1 with an inbuilt encoder and the receiver side consisting of Cell Phone 2, 8870 DTMF decoder and Atmega 16 micro-controller. The programming has been carried out on AVR Bascom®.

A Centrifugal Microfluidics Platform for Potential Application on Immobilization-Free Bead-Based Immunoassays

2013 ◽  
Vol 289 ◽  
pp. 39-44 ◽  
Author(s):  
Qiu Lan Chen ◽  
Ka Lun Cheung ◽  
Yiu Wa Kwan ◽  
Siu Kai Kong ◽  
Ho Pui Ho
Keyword(s):  
High Speed ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Narrow Channel ◽  
Reaction Chamber ◽  
Channel Structure ◽  
Centrifugal Microfluidics ◽  
High Signal ◽  
Fluidic Resistance ◽  
Time Required

In this work, we demonstrate a simple yet convenient centrifugal microfluidics, or lab-on-a-disc (LOAD) platform for bead-based immunoassays. The disc contains a network of passive valves for sample manipulation and a bead-aggregating barrier structure to instead of commonly used immobilization method. The narrow-channel structure not only provides a geometric barrier for retaining the beads, but also significantly increased fluidic resistance which results in lower flow rate and longer reaction time for each reagent in the reaction chamber. Centrifuge-forced beads densification in the small junction area and signal concentrating allows high signal sensing capability. The acceleration speed is optimized for largest signal-to-noise ratio. The device uses different rotation speed to trigger a cascade of flow events. The integrated platform contains all the necessary functional elements for conducting one-step parallel assays through a sequential protocol. For our test device, the total time required to complete an immunoassay experiment is typically under 6 minutes. Through this work we have also shown that the use of a geometric barrier for the aggregation of signaling beads is an effective approach for the enhancement of optical signals in common immunoassays. This flexible design is suitable for a broad range of bead-based immunoassays with low-cost and high-speed operation.

scholarly journals Recent Progress in Fiber Optofluidic Lasing and Sensing

2021 ◽  
Vol 11 (2) ◽  
pp. 262-278
Author(s):  
Xi Yang ◽  
Chaoyang Gong ◽  
Yiling Liu ◽  
Yunjiang Rao ◽  
Mateusz Smietana ◽  
...  
Keyword(s):  
Optical Fiber ◽  
Recent Progress ◽  
Signal To Noise Ratio ◽  
Low Cost ◽  
Microfluidic Channel ◽  
High Sensitivity ◽  
Gain Medium ◽  
High Signal ◽  
Biomedical Analysis ◽  
Sensing Applications

AbstractFiber optofluidic laser (FOFL) integrates optical fiber microcavity and microfluidic channel and provides many unique advantages for sensing applications. FOFLs not only inherit the advantages of lasers such as high sensitivity, high signal-to-noise ratio, and narrow linewidth, but also hold the unique features of optical fiber, including ease of integration, high repeatability, and low cost. With the development of new fiber structures and fabrication technologies, FOFLs become an important branch of optical fiber sensors, especially for application in biochemical detection. In this paper, the recent progress on FOFL is reviewed. We focuse mainly on the optical fiber resonators, gain medium, and the emerging sensing applications. The prospects for FOFL are also discussed. We believe that the FOFL sensor provides a promising technology for biomedical analysis and environmental monitoring.

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