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Imaging artifacts induced by electrical stimulation during conventional fMRI of the brain

Andrea Antal, Marom Bikson, Abhishek Datta, Belen Lafon, Peter Dechent, Lucas C. Parra, Walter Paulus
2014 NeuroImage  
For tACS there was no net effect of the MRI signal.  ...  High-resolution individualized modeling of current flow and induced static magnetic fields suggested a strong coincidence of the change EPI signal with regions of large current density and magnetic fields  ...  For stimulation with AC currents, which had a net-zero charge, no signal was detected.High-resolution Finite Element Method (FEM) modeling of current flow based on the individual anatomy obtained from  ... 
doi:10.1016/j.neuroimage.2012.10.026 pmid:23099102 pmcid:PMC3759658 fatcat:2hccl2juwvbhbpvyuos7oznll4

Deep Denoising Method for Side Scan Sonar Images without High-quality Reference Data [article]

Xiaoteng Zhou, Changli Yu, Xin Yuan, Citong Luo
2021 arXiv   pre-print
This paper proposes a deep denoising method for SSS images without high-quality reference data, which uses one single noise SSS image to perform self-supervised denoising.  ...  Compared with the classical artificially designed filters, the deep denoising method shows obvious advantages.  ...  We introduce peak signal-to-noise ratio (PSNR), structural similarity index matrix (SSIM), flowing index (FI) and edge preservation index (EPI) to quantitatively analyze the results of denoising. 1)  ... 
arXiv:2108.12083v1 fatcat:kvqfge2vejet5o4p3dlsncqnly

Deep Decoding of ℓ_∞-coded Light Field Images [article]

Muhammad Umair Mukati, Xi Zhang, Xiaolin Wu, Søren Forchhammer
2022 arXiv   pre-print
However, their ways of exploiting correlations of multidimensional light field data are complex and are hence not suited for inexpensive light field cameras.  ...  In this work, we propose a novel ℓ_∞-constrained light-field image compression system that has a very low-complexity DPCM encoder and a CNN-based deep decoder.  ...  However, the presence of vertical occlusion does not distort the linearity of EPI-V and thus can be used for effective restoration. Similar is true for EPI-H in presence of horizontal occlusion.  ... 
arXiv:2201.09834v1 fatcat:vx4r3qn4dvaejneqji7mngcj3m

SelfSphNet: Motion Estimation of a Spherical Camera via Self-Supervised Learning

Dabae Kim, Sarthak Pathak, Alessandro Moro, Atsushi Yamashita, Hajime Asama
2020 IEEE Access  
Recently, numerous learning-based methods for camera motion estimation have been proposed.  ...  Next, a photometric reprojection loss estimates the full 6 DoF motion using a depth map generated from the decoupled optical flow.  ...  The results we obtained with SelfSph-Net for the camera motion estimation were more accurate compared to those obtained using fully supervised learning. II.  ... 
doi:10.1109/access.2020.2977109 fatcat:waeiabwr4zhkvk4i2bz7pxgn2e

"Select and retrieve via direct upsampling" network (SARDU-Net): a data-driven, model-free, deep learning approach for quantitative MRI protocol design [article]

Francesco Grussu, Stefano B. Blumberg, Marco Battiston, Lebina S. Kakkar, Hongxiang Lin, Andrada Ianus, Torben Schneider, Saurabh Singh, Roger Bourne, Shonit Punwani, David Atkinson, Claudia A. M. Gandini Wheeler-kingshott (+3 others)
2020 bioRxiv   pre-print
Purpose: We introduce "Select and retrieve via direct upsampling" network (SARDU-Net), a data-driven deep learning framework for model-free quantitative MRI (qMRI) experiment design.  ...  The algorithm consists of two deep neural networks (DNNs) that are trained jointly end-to-end: a selector, identifying a subset of input qMRI measurements, and a predictor, estimating fully-sampled signals  ...  Jin for useful discussion.  ... 
doi:10.1101/2020.05.26.116491 fatcat:tuon35oeujctdpzvkz7o5nkhg4

k-Space Deep Learning for Reference-free EPI Ghost Correction [article]

Juyoung Lee, Yoseob Han, Jae-Kyun Ryu, Jang-Yeon Park, Jong Chul Ye
2019 arXiv   pre-print
For the accelerated EPI data, the same neural network is trained to directly estimate the interpolation kernels for missing k-space data from both ghost and subsampling.  ...  learning for EPI ghost correction is highly robust and fast, and can be combined with acceleration, so that it can be used as a promising correction tool for high-field MRI without changing the current  ...  Reconstruction flow for (a) ALOHA-based ghost artifact removal, and (b) the proposed k -space deep learning for ghost artifact removal.  ... 
arXiv:1806.00153v3 fatcat:n477fu3rrjbr7bwsl65uowpczy

Multi-vendor reliability of arterial spin labeling perfusion MRI using a near-identical sequence: Implications for multi-center studies

Henri J.M.M. Mutsaerts, Matthias J.P. van Osch, Fernando O. Zelaya, Danny J.J. Wang, Wibeke Nordhøy, Yi Wang, Stephen Wastling, Maria A. Fernandez-Seara, E.T. Petersen, Francesca B. Pizzini, Sameeha Fallatah, Jeroen Hendrikse (+6 others)
2015 NeuroImage  
Reproducibility was evaluated by means of quantitative cerebral blood flow (CBF) agreement and inter-session variation, both on a region-of-interest (ROI) and voxel level.  ...  In this study, we compare a single identical 2D gradient-echo EPI pseudo-continuous ASL (PCASL) sequence implemented on 3T scanners from three vendors (General Electric Healthcare, Philips Healthcare and  ...  The authors are grateful to M Kleppestø and M Skurdal for help with data collection and to W.V. Potters for help with post-processing.  ... 
doi:10.1016/j.neuroimage.2015.03.043 pmid:25818685 fatcat:gb6jgstz7nen5ehs7nvschwwoe

An Auxiliary Method Based on Hyperspectral Reflectance for Presentation Attack Detection

Shiwei Li, Mohsen Ardabilian, Abdel-Malek Zine
2019 2019 15th International Conference on Signal-Image Technology & Internet-Based Systems (SITIS)  
The results show that Skin-Net can estimate very similar reflectance. The mean error of all 30 samples validations is 3.66e −05 .  ...  Wen et al. study on an efficient and robust PAD algorithm based on image distortion analysis to separate genuine and spoof faces [10] .  ... 
doi:10.1109/sitis.2019.00042 dblp:conf/sitis/LiAZ19 fatcat:sinussvsvzak7pzomwdhzvcbie

Diffusion Tensor Imaging and Its Application to Traumatic Brain Injury: Basic Principles and Recent Advances

Ping-Hong Yeh, Terrence R. Oakes, Gerard Riedy
2012 Open Journal of Medical Imaging  
Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for  ...  Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining  ...  MR spectroscopic imaging for brain metabolites, perfusion imaging for cerebral flow change, susceptibility weighted imaging (SWI) for microhemorrhages, and FDG-PET for glucose utilization [215, 216] .  ... 
doi:10.4236/ojmi.2012.24025 fatcat:h55evmhkkndapaczqmptddpguu

Foundations of advanced magnetic resonance imaging

Roland Bammer, Stefan Skare, Rexford Newbould, Chunlei Liu, Vincent Thijs, Stefan Ropele, David B. Clayton, Gunnar Krueger, Michael E. Moseley, Gary H. Glover
2005 NeuroRx  
However, EPI suffers from its own problems: EPI is limited by lower resolutions (ϳ128 ϫ 128), image blurring, localized signal loss, and image distortions. 28 Distortions and signal loss occur predominantly  ...  Pulse sequences for DWI Diffusion-weighted single-shot EPI.  ... 
doi:10.1602/neurorx.2.2.167 pmid:15897944 pmcid:PMC1064985 fatcat:vyfeyhkvtvfe3kg6iyxxgzzrgu

Foundations of advanced magnetic resonance imaging

Roland Bammer, Stefan Skare, Rexford Newbould, Chunlei Liu, Vincent Thijs, Stefan Ropele, David B. Clayton, Gunnar Krueger, Michael E. Moseley, Gary H. Glover
2005 Neurotherapeutics  
However, EPI suffers from its own problems: EPI is limited by lower resolutions (ϳ128 ϫ 128), image blurring, localized signal loss, and image distortions. 28 Distortions and signal loss occur predominantly  ...  Pulse sequences for DWI Diffusion-weighted single-shot EPI.  ... 
doi:10.1007/bf03206665 fatcat:a66utm5yn5dwxfvxx5s7hwg6ve

Correction of physiologically induced global off-resonance effects in dynamic echo-planar and spiral functional imaging

Josef Pfeuffer, Pierre-Francois Van de Moortele, Kamil Ugurbil, Xiaoping Hu, Gary H. Glover
2002 Magnetic Resonance in Medicine  
The DORK correction significantly reduced respirationinduced noise (image shift for EPI, blurring for spiral, ghosting for segmented acquisition).  ...  The correction uses phase information from the center of k-space and a navigator echo and is illustrated with dynamic scans of single-shot and segmented EPI and, for the first time, spiral imaging of the  ...  ACKNOWLEDGMENTS The authors thank Shantanu Sarkar for help with the spiral reconstruction, John Strupp for help with the EPI reconstruction, and Gregor Adriany, Peter Andersen, and Hellmut Merkle for hardware  ... 
doi:10.1002/mrm.10065 pmid:11810679 fatcat:xqiwik2afjdcpljvuapgtucl2i

Microscopic PIV measurements for electro-osmotic flows in PDMS microchannels

M. J. Kim, K. D. Kihm
2004 Journal of Visualization  
Comparisons of experimental results among various micro-configurations show feasibilities of the electro-osmotic flows to use for micro-pumping and micro-fluidic flow control.  ...  Electro-osmosis is the flow produced by the action of an electric field on a fluid with a net charge, which is created by the Zeta potential and confined in the Debye layer.  ...  Paul Cremer for their assistance. Support from the TAMU Interdisciplinary Research Program is acknowledged and appreciated for the present work.  ... 
doi:10.1007/bf03181583 fatcat:gofrwuukczdffccf4k6k32tzmi

Learning Dynamic Interpolation for Extremely Sparse Light Fields with Wide Baselines [article]

Mantang Guo, Jing Jin, Hui Liu, Junhui Hou
2021 arXiv   pre-print
Specifically, with the estimated geometric relation between input views, we first construct a lightweight neural network to dynamically learn weights for interpolating neighbouring pixels from input views  ...  optical-flow model.  ...  used them to separately train two models, denoted as Ours (RAFT) and Ours (PWC-Net), respectively.  ... 
arXiv:2108.07408v2 fatcat:mqx4g3fisfdwtfh7efnt3kmea4

Laminar dynamics of high amplitude beta bursts in human motor cortex

James J Bonaiuto, Simon Little, Samuel A Neymotin, Stephanie R Jones, Gareth R Barnes, Sven Bestmann
2021 NeuroImage  
This approach pinpoints the generation of beta bursts in human motor cortex to distinct excitatory synaptic inputs to deep and superficial cortical layers, which drive current flow in opposite directions  ...  More generally, we demonstrate the ability for uncovering the laminar dynamics of event-related neural signals in human non-invasive recordings.  ...  geometric distortions of the EPI data due to B0 field inhomogeneity.  ... 
doi:10.1016/j.neuroimage.2021.118479 pmid:34407440 pmcid:PMC8463839 fatcat:6phu4jzmhzbn5bxdlj6p5dmqdi
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