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Search Publications by: Karl Stupic (Fed)

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Displaying 26 - 50 of 64

Low-Field Magnetic Resonance Imaging of Roots in Intact Clayey and Silty Soils

July 1, 2020
Author(s)
George Bagnall, Cristine` Morgan, Matthew Rosen, Mark Conradi, Stephen Altobelli, Dean Kuethe, Haly Neely, Neha Koonjoo, Bo Zhu, Karl Stupic, John Mullet, Brock Weers, Eiichi Fukushima, William Rooney
The development of a robust method to non-invasively visualize root morphology in natural soils has been hampered by the opaque, physical, and structural properties of soils. In this work we describe a novel technology, low field magnetic resonance imaging

Low-field magnetic resonance imaging of roots in intact clayey and silty soils

March 27, 2020
Author(s)
Mark S. Conradi, Stephen A. Altobelli, Dean O. Kuethe, Matthew S. Rosen, Neha Koonjoo, Bo Zhu, Karl Stupic, William L. Rooney, John E. Mullet, Brock Weers, G. Cody Bagnall, Haly Neely, Eiichi Fukushima, Cristine Morgan
The development of a robust method to non-invasively visualize root morphology in natural soils has been hampered by the opaque nature, chemical composition, and physical structure of soils. We describe here a novel technology—low field magnetic resonance

Progress Towards Standards for Quantitative MRI (qMRI) and Outstanding Needs

January 24, 2019
Author(s)
Kathryn E. Keenan, Joshua R. Biller, Michael A. Boss, Adele P. Peskin, Karl F. Stupic, Stephen E. Russek, Jana Delfino, Mark Does, Jeffrey L. Evelhoch, Mark Griswold, Jeffrey Gunter, R Scott Hinks, Stuart Hoffman, Geena Kim, Riccardo Lattanzi, Xiaojuan Li, Luca Marinelli, Pratik Mukherjee, Robert J. Nordstrom, Elena Perez, Berkman Sahiner, Natalie J. Serkova, Amita Shukla-Dave, Michael Steckner, Lisa J. Wilmes, Holden Wu, Huiming Zhang, Edward F. Jackson, Daniel Sullivan
The National Institute of Standards and Technology (NIST) MRI Standards project held a one-day workshop on August 4, 2017 on campus in Boulder, CO. The goal of the workshop was to evaluate the advances in quantitative MRI (qMRI) since the last NIST

Nano-Sized Ferrite Particles for Magnetic Resonance Imaging Thermometry

September 8, 2018
Author(s)
Janusz H. Hankiewicz, J A. Stoll, John Stroud, J Davidson, K L. Livesey, K Tvrdy, Alexana Roshko, Stephen E. Russek, Karl Stupic, P Bilski, Robert E. Camley
Recently, we reported the use of magnetic particles as temperature indicators in magnetic resonance imaging thermometry (tMRI). In this method, the brightness of the MR image changes with temperature due to a temperature-dependent magnetic field

Magnetic Resonance Imaging Biomarker Calibration Service: Proton Spin Relaxation Times

May 3, 2018
Author(s)
Michael A. Boss, Andrew M. Dienstfrey, Zydrunas Gimbutas, Kathryn E. Keenan, Jolene D. Splett, Karl F. Stupic, Stephen E. Russek
This document describes the calibration service to measure proton spin relaxation times, T1 and T2, of materials used in phantoms (calibration artifacts) to verify the accuracy of MRI-based quantitative measurements. Proton spin relaxation times are used

Zinc Doped Copper Ferrite Particles as Temperature Sensors for Magnetic Resonance Imaging

December 27, 2017
Author(s)
Karl Stupic, Janusz H. Hankiewicz, Zbigniew Celinski, Robert E. Camley, Marek Przybylski, Jan Zukrowski, Nick Anderson, Noweir Alghamdi, Nicholas Hammelev
We investigate the use of Cu0.35Zn0.65Fe2O4 particles as temperature-dependent sensors in magnetic resonance imaging (MRI). This material has a Curie temperature near 290 K, but in the large magnetic fields found in MRI scanners there is a significant

MRI Birdcage RF Coil Resonance with Uncertainty and Relative Error Convergence Rates

October 4, 2017
Author(s)
Jeffrey T. Fong, Nathanael A. Heckert, James J. Filliben, Pedro V. Marcal, Robert Rainsberger, Karl F. Stupic, Stephen E. Russek
In a magnetic resonance imaging (MRI) system, it is necessary to excite the nuclei of a patient into coherent precession for imaging. This requires a coupling between the nuclei and a source of radio frequency (RF) power using a transmitter. To receive a

Quantitative Magnetic Resonance Imaging Phantoms: A Review and the Need for a System Phantom

October 4, 2017
Author(s)
Kathryn E. Keenan, Maureen Ainslie, Alexander J. Barker, Michael A. Boss, Kim M. Cecil, Cecil Charles, Thomas L. Chenevert, Laurence Clarke, Jeffrey L. Evelhoch, Paul Finn, Guoying Liu, Stephen E. Russek, Karl F. Stupic, Joshua D. Trzasko, Chun Yuan, Jie Zheng
The MRI community is using quantitative mapping techniques to complement qualitative imaging. For quantitative imaging to reach its full potential, it is necessary to analyze measurements across systems and longitudinally. Clinical use of quantitative

Accuracy, repeatability and interplatform reproducibility measurements of T 1 quantification methods used for DCE-MRI: results from a multicenter phantom study.

August 16, 2017
Author(s)
Octavia Bane, Stefanie J. Hectors, Mathilde Wagner, Lori L. Arlinghaus, Madhava P. Aryal, Yue Cao, Thomas L. Chenevert, Fiona Fennessy, Wei Huang, Nola M. Hylton, Jayashree Kalpathy-Cramer, Katy Keenan, Dariya I. Malyarenko, Robert V. Mulkern, David C. Newitt, Stephen E. Russek, Karl Stupic, Michael A. Boss
Purpose: To determine the in vitro accuracy, test-retest repeatability, and interplatform reproducibility of T 1 quantification protocols used for dynamic contrast-enhanced MRI at 1.5 and 3 T. Methods: A T 1 phantom with 14 samples was imaged at eight