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https://www.readbyqxmd.com/read/28227941/a-three-element-1-h-31-p-dual-tuned-array-for-magnetic-resonance-spectroscopy-at-4-7-t
#1
Matthew D Wilcox, Romina Del Bosque, Kurt Parizek, Jeremy Sia, Edwin D Eigenbrodt, Mary P McDougall, Matthew D Wilcox, Romina Del Bosque, Kurt Parizek, Jeremy Sia, Edwin D Eigenbrodt, Mary P McDougall, Jeremy Sia, Romina Del Bosque, Kurt Parizek, Mary P McDougall, Matthew D Wilcox, Edwin D Eigenbrodt
This work describes the construction and testing of a three-element, double-tuned receive array and transmit coils for (31)P-(1)H spectroscopy and imaging. The receive coils were geometrically-decoupled, single-loop surface coils and the transmit coils were concentric saddle coils. The coils were used to examine a physiologically-modeled CNC-milled phantom. The receive coil array was able to improve SNR while also providing gross localization of the (1)H and (31)P signals.
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227940/magnetic-resonance-imaging-receiver-coil-decoupling-using-circumferential-shielding-structures
#2
Jhy-Neng Tasso Yeh, Fa-Hsuan Lin, Jhy-Neng Tasso Yeh, Fa-Hsuan Lin, Jhy-Neng Tasso Yeh, Fa-Hsuan Lin
We propose a flexible phased-array design using circular coils with circumferential shielding structure to achieve robust decoupling between coil elements when the array is either bended or on a flat plane. Two types of circumferential shielding were tested through numerical simulation and imaging experiment. The results demonstrated that our arrays have good decoupling between coils when they are on a curved surface with S21 <; -16.72 dB. Both types perform higher SNR images than a commercially available 32-channel adult head coil array...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227939/effects-of-coplanar-shielding-for-high-field-mri
#3
Joseph V Rispoli, Matthew D Wilcox, Samantha By, Steven M Wright, Mary P McDougall, Joseph V Rispoli, Matthew D Wilcox, Samantha By, Steven M Wright, Mary P McDougall, Matthew D Wilcox, Steven M Wright, Samantha By, Mary P McDougall, Joseph V Rispoli
This work investigates the efficacy of "coplanar shielding," in which copper shields are oriented concentric and coplanar to the RF coils rather than implemented as a full ground plane behind them. Following FDTD simulations to determine optimal shielding parameters, two coil geometries were constructed: a circular loop surface coil and a half-volume five-element receive array. Each was evaluated using bench measurements with and without coplanar shielding. Imaging, including accelerated SENSE imaging, was performed with the shielded and unshielded receive arrays on a whole-body 7T scanner...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227921/directionally-sensitive-peripheral-nerve-recording-bipolar-nerve-cuff-design
#4
Parisa Sabetian, Milos R Popovic, Paul B Yoo, Parisa Sabetian, Milos R Popovic, Paul B Yoo
Although bipolar nerve cuff electrodes (NCEs) are used in clinical neurostimulation therapies (e.g., epilepsy, obstructive sleep apnea), the use of this electrode as part of a closed-up controlled system is very limited. The literature points to high noise content (i.e., poor signal-to-noise ratio, SNR) as the primary reason for not using bipolar NCEs to record neural activity. In fact, over the past several decades, the pseudo-tripolar NCEs, the symmetric configuration of this electrode array (i.e., electrically-shorted side contacts) makes it very difficult to obtain directional information from the recorded neural activity (efferent vs...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227896/intarsia-sensorized-band-and-textrodes-for-real-time-myoelectric-pattern-recognition
#5
Shannon Brown, Max Ortiz-Catalan, Joel Petersson, Kristian Rodby, Fernando Seoane, Shannon Brown, Max Ortiz-Catalan, Joel Petersson, Kristian Rodby, Fernando Seoane, Max Ortiz-Catalan, Fernando Seoane, Kristian Rodby, Shannon Brown, Joel Petersson
Surface Electromyography (sEMG) has applications in prosthetics, diagnostics and neuromuscular rehabilitation. Self-adhesive Ag/AgCl are the electrodes preferentially used to capture sEMG in short-term studies, however their long-term application is limited. In this study we designed and evaluated a fully integrated smart textile band with electrical connecting tracks knitted with intarsia techniques and knitted textile electrodes. Real-time myoelectric pattern recognition for motor volition and signal-to-noise ratio (SNR) were used to compare its sensing performance versus the conventional Ag-AgCl electrodes...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227802/developing-a-one-channel-bci-system-using-a-dry-claw-like-electrode
#6
Xuhong Guo, Weihua Pei, Yijun Wang, Qiang Gui, He Zhang, Xiao Xing, Yong Huang, Hongda Chen, Ruicong Liu, Yuanyuan Liu, Xuhong Guo, Weihua Pei, Yijun Wang, Qiang Gui, He Zhang, Xiao Xing, Yong Huang, Hongda Chen, Ruicong Liu, Yuanyuan Liu, Hongda Chen, Yijun Wang, Weihua Pei, Yuanyuan Liu, Ruicong Liu, He Zhang, Qiang Gui, Xuhong Guo, Yong Huang, Xiao Xing
An eight-class SSVEP-based BCI system was designed and demonstrated in this study. To minimize the complexity of the traditional equipment and operation, only one work electrode was used. The work electrode was fabricated in our laboratory and designed as a claw-like structure with a diameter of 15 mm, featuring 8 small fingers of 4mm length and 2 mm diameter, and the weight was only 0.1g. The structure and elasticity can help the fingers pass through the hair and contact the scalp when placed on head. The electrode was capable to collect evoked brain activities such as steady-state visual evoked potentials (SSVEPs)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227801/reference-configurations-for-ear-eeg-steady-state-responses
#7
Simon L Kappel, Christian B Christensen, Kaare B Mikkelsen, Preben Kidmose, Simon L Kappel, Christian B Christensen, Kaare B Mikkelsen, Preben Kidmose, Kaare B Mikkelsen, Preben Kidmose, Christian B Christensen, Simon L Kappel
Ear-EEG is a non-invasive EEG recording method, where EEG is recorded from electrodes placed in the ear. Ear-EEG could be implemented into hearing aids, and provide neurofeedback for e.g. objective hearing assessment through measurements of the auditory steady-state response. In cases where the objective is to measure a specific feature of an event-related potential, there will be a subject specific optimal reference configuration. This work presents a method for optimizing the reference configuration for steady-state type potentials...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227765/distribution-aware-estimation-of-the-minimum-achievable-uncertainty-in-diffusion-tensor-imaging-dti
#8
Andrea Duggento, Marco Giannelli, Carlo Tessa, Simona Lanzafame, Maria Guerrisi, Nicola Toschi, Andrea Duggento, Marco Giannelli, Carlo Tessa, Simona Lanzafame, Maria Guerrisi, Nicola Toschi, Nicola Toschi, Maria Guerrisi, Marco Giannelli, Carlo Tessa, Simona Lanzafame, Andrea Duggento
Diffusion tensor imaging (DTI) provides exquisite sensitivity to structural and microstructural characteristics of brain tissue, and is routinely employed in advanced neuroimaging applications. DTI is commonly performed using intrinsically noisy echo-planar imaging techniques and poses high demands both on scanner performance and on in-scanner subject time, which in turn is directly related to the number of diffusion-weighting direction one requires. While DTI-derived indices such as fractional anisotropy (FA), diffusion tensor trace and anisotropy mode have proven extremely useful in characterizing disease-related aberrations, their estimation is commonly performed using fitting routines that do not properly take into account MRI noise distribution...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227744/classification-of-non-weight-bearing-lower-limb-movements-towards-a-potential-treatment-for-phantom-limb-pain-based-on-myoelectric-pattern-recognition
#9
Eva Lendaro, Max Ortiz-Catalan, Eva Lendaro, Max Ortiz-Catalan, Max Ortiz-Catalan, Eva Lendaro
Research in myoelectric pattern recognition (MPR) for the prediction of motor volition has primarily focused on the upper limbs. Recent studies in the lower limbs have mainly concentrated on prosthetic control, while MPR for lower limb rehabilitation purposes has received little attention. In this work we investigated the viability of a MPR system for the prediction of four degrees of freedom controlled in a near natural or physiologically appropriate fashion. We explored three different electrode configurations for acquiring electromyographic (EMG) signals: two targeted (bipolar and monopolar) and one untargeted (electrodes equally spaced axially)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227714/an-efficient-ecg-baseline-removal-filter-based-on-frequency-response-masking-technique-for-wearable-applications
#10
Boxiao Liu, Guoxing Wang, Yong Lian, Boxiao Liu, Guoxing Wang, Yong Lian, Guoxing Wang, Yong Lian, Boxiao Liu
This paper presents a computationally efficient FIR (finite impulse response) filter for ECG (electrocardiogram) baseline wander removal. The proposed filter is based on frequency-response masking (FRM) technique, which reduces the number of multiplications by 90% compared to the conventional FIR filter. The filter specifications are optimized to obtain the highest SNR (signal-to-noise ratio) while minimizing the number of filter coefficients. The SNR performance of the proposed filter is evaluated using ECG signals from MIT-BIH Arrhythmia Database with added baseline noises from MIT-BIH Noise Stress Test Database...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227565/a-simulation-analysis-of-the-variability-of-the-roving-level-hearing-test
#11
Greg D Watkins, Brett A Swanson, Gregg J Suaning, Greg D Watkins, Brett A Swanson, Gregg J Suaning, Greg D Watkins, Brett A Swanson, Gregg J Suaning
In the study of auditory prostheses, the Speech Recognition Threshold (SRT) is the Signal to Noise Ratio (SNR) at which 50% of words are correctly identified. SRT is typically measured using an adaptive procedure wherein speech is presented at a fixed sound pressure level (SPL) and the noise level is varied according to the subject's responses. A roving level SRT test has been used by researchers with the goal of including the effectiveness of Automatic Gain Control (AGC) systems in SRT measurements. The roving method presents speech at three different SPLs with the level for each sentence chosen pseudo-randomly, while adaptively varying the SNR...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227519/kernel-temporal-enhancement-approach-for-loreta-source-reconstruction-using-eeg-data
#12
Cristian A Torres-Valencia, M Claudia Joana Santamaria, Mauricio A Alvarez, Cristian A Torres-Valencia, M Claudia Joana Santamaria, Mauricio A Alvarez, Mauricio A Alvarez, Cristian A Torres-Valencia
Reconstruction of brain sources from magnetoencephalography and electroencephalography (M/EEG) data is a well known problem in the neuroengineering field. A inverse problem should be solved and several methods have been proposed. Low Resolution Electromagnetic Tomography (LORETA) and the different variations proposed as standardized LORETA (sLORETA) and the standardized weighted LORETA (swLORETA) have solved the inverse problem following a non-parametric approach, that is by setting dipoles in the whole brain domain in order to estimate the dipole positions from the M/EEG data and assuming some spatial priors...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227407/recursive-feature-elimination-for-biomarker-discovery-in-resting-state-functional-connectivity
#13
Hariharan Ravishankar, Radhika Madhavan, Rakesh Mullick, Teena Shetty, Luca Marinelli, Suresh E Joel, Hariharan Ravishankar, Radhika Madhavan, Rakesh Mullick, Teena Shetty, Luca Marinelli, Suresh E Joel, Suresh E Joel, Teena Shetty, Luca Marinelli, Rakesh Mullick, Hariharan Ravishankar, Radhika Madhavan
Biomarker discovery involves finding correlations between features and clinical symptoms to aid clinical decision. This task is especially difficult in resting state functional magnetic resonance imaging (rs-fMRI) data due to low SNR, high-dimensionality of images, inter-subject and intra-subject variability and small numbers of subjects compared to the number of derived features. Traditional univariate analysis suffers from the problem of multiple comparisons. Here, we adopt an alternative data-driven method for identifying population differences in functional connectivity...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227375/motion-invariant-contrast-enhancement-of-optical-imaging-data-in-the-gradient-domain
#14
Philipp Flotho, Alejandro Romero-Santiago, Karsten Schwerdtfeger, Jacek Szczygielski, Matthias Hulser, Lars Haab, Daniel J Strauss, Philipp Flotho, Alejandro Romero-Santiago, Karsten Schwerdtfeger, Jacek Szczygielski, Matthias Hulser, Lars Haab, Daniel J Strauss, Daniel J Strauss, Alejandro Romero-Santiago, Jacek Szczygielski, Karsten Schwerdtfeger, Philipp Flotho, Lars Haab
Functional optical imaging (OI) of intrinsic signals (like blood oxygenation coupled reflection changes) and of extrinsic properties of voltage sensitive probes (like voltage-sensitive dyes (VSD)) forms a group of neuroimaging techniques that possess up to date highest temporal and spatial resolution on a meso-to macroscopic scale. An inherent problem of OI is a very low signal to noise ratio (SNR), which restricts the recordings to be completely motionless and requires detailed knowledge of the properties of the different noise sources...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227312/improving-quality-and-intelligibility-of-speech-using-single-microphone-for-the-broadband-fmri-noise-at-low-snr
#15
Chetan Vahanesa, Chandan K A Reddy, Issa M S Panahi, Chetan Vahanesa, Chandan K A Reddy, Issa M S Panahi, Chetan Vahanesa, Issa M S Panahi, Chandan K A Reddy
Functional Magnetic Resonance Imaging (fMRI) is used in many diagnostic procedures for neurological related disorders. Strong broadband acoustic noise generated during fMRI scan interferes with the speech communication between the physician and the patient. In this paper, we propose a single microphone Speech Enhancement (SE) technique which is based on the supervised machine learning technique and a statistical model based SE technique. The proposed algorithm is robust and computationally efficient and has capability to run in real-time...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227301/an-adapted-double-threshold-protocol-for-spastic-muscles
#16
Pedro M Vieira, Joao F Ferreira, Pedro R Gomes, Carlos S Lima, Pedro M Vieira, Joao F Ferreira, Pedro R Gomes, Carlos S Lima, Pedro M Vieira, Joao F Ferreira, Pedro R Gomes, Carlos S Lima
The onset of muscle contraction has been an important element in the understanding of human motor control system as well as in the development of medical devices. This task is problematic in the study of spasticity using surface Electromyography (sEMG). In fact, spasticity is characterized by involuntary muscle contractions that can be seen as both, a non-stationary background if they are weak or a severe non-stationary EMG signal if they are strong. In other hand, these sEMG signals present a very low signal to noise ratio, beyond the added noise that contaminates this signal...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227296/fluorescence-background-removal-method-for-biological-raman-spectroscopy-based-on-empirical-mode-decomposition
#17
Maritza Leon-Bejarano, Guadalupe Dorantes-Mendez, Miguel Ramirez-Elias, Martin O Mendez, Alfonso Alba, Ildefonso Rodriguez-Leyva, M Jimenez, Maritza Leon-Bejarano, Guadalupe Dorantes-Mendez, Miguel Ramirez-Elias, Martin O Mendez, Alfonso Alba, Ildefonso Rodriguez-Leyva, M Jimenez, Ildefonso Rodriguez-Leyva, Alfonso Alba, M Jimenez, Martin O Mendez, Miguel Ramirez-Elias, Maritza Leon-Bejarano, Guadalupe Dorantes-Mendez
Raman spectroscopy of biological tissue presents fluorescence background, an undesirable effect that generates false Raman intensities. This paper proposes the application of the Empirical Mode Decomposition (EMD) method to baseline correction. EMD is a suitable approach since it is an adaptive signal processing method for nonlinear and non-stationary signal analysis that does not require parameters selection such as polynomial methods. EMD performance was assessed through synthetic Raman spectra with different signal to noise ratio (SNR)...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227252/linear-methods-for-reducing-emg-contamination-in-peripheral-nerve-motor-decodes
#18
Zachary B Kagan, Suzanne Wendelken, David M Page, Tyler Davis, Douglas T Hutchinson, Gregory A Clark, David J Warren, Zachary B Kagan, Suzanne Wendelken, David M Page, Tyler Davis, Douglas T Hutchinson, Gregory A Clark, David J Warren, Gregory A Clark, Zachary B Kagan, David J Warren, David M Page, Suzanne Wendelken, Tyler Davis, Douglas T Hutchinson
Signals recorded from the peripheral nervous system (PNS) with high channel count penetrating microelectrode arrays, such as the Utah Slanted Electrode Array (USEA), often have electromyographic (EMG) signals contaminating the neural signal. This common-mode signal source may prevent single neural units from successfully being detected, thus hindering motor decode algorithms. Reducing this EMG contamination may lead to more accurate motor decode performance. A virtual reference (VR), created by a weighted linear combination of signals from a subset of all available channels, can be used to reduce this EMG contamination...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28227084/development-of-data-acquisition-components-for-simultaneous-recording-of-3d-epicardial-and-surface-ecg-signals-in-the-langendorff-perfusion-apparatus
#19
Ryan Wade Selby, Anup Jonchhe, Chen Kaplan, Coeli M Lopes, Behnaz Ghoraani, Ryan Wade Selby, Anup Jonchhe, Chen Kaplan, Coeli M Lopes, Behnaz Ghoraani, Chen Kaplan, Behnaz Ghoraani, Anup Jonchhe, Coeli M Lopes, Ryan Wade Selby
Sudden Cardiac Death (SCD) claims 7 million lives per year. The importance of myocardial electrogram (EGM) repolarization alternans and surface electrocardiogram (ECG) T-wave alternans is gaining traction for understanding the underlying SCD mechanisms. However, the relationship between the 3D spatial distribution of myocardial EGMs and surface ECG with respect to SCD has yet to be investigated. To make this happen, a modified data acquisition system has been developed and fabricated in conjunction with the Langendorff perfusion system to enable simultaneous recording and analysis of the 3D spatial distribution of myocardial EGMs and the surface ECG...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
https://www.readbyqxmd.com/read/28226994/high-dielectric-material-in-mri-numerical-assessment-of-the-reduction-of-the-induced-local-power-on-implanted-cardiac-leads
#20
Eugenio Mattei, Elena Lucano, Federica Censi, Leonardo M Angelone, Giovanni Calcagnini, Eugenio Mattei, Elena Lucano, Federica Censi, Leonardo M Angelone, Giovanni Calcagnini, Eugenio Mattei, Giovanni Calcagnini, Elena Lucano, Leonardo M Angelone, Federica Censi
High dielectric materials (HDM) have been proposed in magnetic resonance imaging (MRI) to increase the signal-to-noise ratio (SNR) of the images acquired while reducing the radiofrequency (RF) absorption in tissue. The aim of this study is to assess the potential merit of using HDM to reduce power induced at the tip of an endocardial lead in patients undergoing MRI. Numerical simulations were performed using a commercial finite-differences time-domain (FDTD) software to model the RF field generated by a birdcage body coil at 64 MHz on a human body model...
August 2016: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
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