Roger C. Barr
Professor of Biomedical Engineering
Quantitative Electrophysiology - Activation of the Heart. Simulation studies are being conducted on the activation process in cardiac tissue. To carry this out it is necessary to describe quantitatively the electrical (nonlinear) behavior of the cell membrane as well as to describe the electrical ``load" (i.e. the electrical structure and conductivities of the intracellular and extracellular medium). For studies which emphasize activation alone the Hodgkin-Huxley and Ebihara-Johnson membrane models have been used. Where recovery is important the Beeler-Reuter and DiFrancesco-Noble models have been introduced.
Regarding the passive conductive properties of the cardiac muscle, because of its syncytial nature (arising from multiple low resistance intercellular junctions) the intracellular and interstitial space can be regarded as continua though coupled at all points through the cell membrane. This constitutes what has been called the bidomain model and is the basis for a partial differential equation description of the fields of interest. The directional differences in conductivity arising from the fiber orientation and myofibril structure can be taken into account by using an anisotropic conductivity tensor. In general the ratio of conductivities in the intracellular and interstitial spaces are unequal, according to the isolated experiments in the literature.
To date simulations have been carried out to describe current flow patterns that arise under different assumed anisotropy conditions for both electrotonus and action potential conditions. In one study the activation isochrones resulting from a point stimulation were determined for a two-dimensional homogeneous (though anisotropic) tissue. Based on the assumption of equal anisotropy ratio simulations have been performed for a semi-infinite and cylindrical bundle of tissue describing the character of the intracellular and interstitial field as a function of depth into the tissue from the extracellular (bounding) space. One sees a considerable non-uniformity of magnitude near the surface so that measurements typically made at the surface may not be representative of interior wave shape. In particular a wave initiated at one end of a cylindrical bundle will develop a curved phase front (curved isochrones). Other important consequences have to do with the resulting source strength, velocity of propagation, e The above research is ultimately directed toward models which may help elucidate the initiation of cardiac arrhythmias.
We are also interested in developing cardiac muscle models that will help clarify and elucidate the electrophysiological processes underlying defibrillation. We have examined one-dimensional models to date and pointed out the important role of the modified bidomain model which includes the junctional resistance. This work is limited to steady-state solutions; results emphasize a strong relationship to the size of the intercellular junction. Current efforts are directed at an examination of the transient response to a defibrillatory pulse by including the membrane capacitance. Still further efforts are based on including a quantitative description of the membrane ionic channels themselves. Our goal is eventual extension to a three-dimensional model.
Further work is planned that will extend the aforementioned projects more fully to three dimensions, to arbitrary anisotropy, and to actual heart geometry. In particular we would like to extend work on one-dimensional propagation models which includes the discontinuous structure arising from intercellular junctions to three dimensions. Interest centers on explaining both normal and abnormal experimental studies.
Neural Stimulation. We have been interested in developing and examining models arising from practical applications of functional electrical stimulation. Work completed to date includes the characterization and behavior of cuff electrodes which demonstrate the conditions under which unidirectional propagation results. We have also considered the response of a nerve bundle arising from a point stimulation source. Of particular interest was the determination of the effect of fiber position within a bundle on excitation threshold. In carrying out this latter study, the effect of current redistribution from interstitial to intracellular space was included, but only under steady-state conditions. This work needs to be extended to the transient case.
The effect of electrode shape (electrode array) on stimulation properties is also of interest and will be considered in the future. The reciprocal problem, namely an investigation of the effect of electrode size and shape in electromyography, is currently being studied.
Electrophysiological Sources. When excitable tissue (nerve or muscle) is stimulated, the result is an action potential and associated action currents. The action currents, by depolarizing membranes adjacent to the site undergoing activation, serve to spread the activation --- and in this way result in the propagation of the impulse. The action currents fill the entire conducting region, according to the laws of electricity. As a result potential fields surrounding and at a distance from active processes can be detected and measured. Familiar examples are the electrocardiogram, electromyogram, etc.
The relationship between underlying electrical activation processes(sources) and the potential fields they produce is of great interest. If carefully characterized the opportunity is present for learning about cellular processes based on external (noninvasive) measurements. This is important not only in clinical situations, but in basic research as well.
The goal of this research is to develop quantitative formulations for the electrical generators associated with activation processes. The case of a single cell in a uniform volume conductor and its extension to the cylindrical fiber has been well studied over the last twenty years. Interest now centers on multi fiber preparations including muscle and nerve bundles, cardiac muscle, and smooth muscle. Such formulations are needed during activation as well as recovery. This is particularly important in the study of cardiac tissue since recovery is not propagated.
As part of this study a particular effort is directed to a study of cardiac recovery and the T-wave. New experimental methods provide an opportunity, for the first time, to describe the action potential waveforms throughout the heart providing a useful database. The goal is the quantitative analysis of the origins of the T-wave as measured both on the torso and on the heart.
Current Research Interests
Current Appointments & Affiliations
- Professor of Biomedical Engineering, Biomedical Engineering, Pratt School of Engineering 1979
- Faculty Network Member of the Duke Institute for Brain Sciences, Duke Institute for Brain Sciences, University Institutes and Centers 2011
- Bass Fellow, Biomedical Engineering, Pratt School of Engineering 2013
Contact Information
- 1387 CIEMAS, Durham, NC 27708
- Box 90281, Durham, NC 27708-0281
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roger.barr@duke.edu
(919) 660-5123
- Background
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Education, Training, & Certifications
- Ph.D., Duke University 1968
- B.S., Duke University 1964
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Previous Appointments & Affiliations
- Associate Professor in Pediatrics, Pediatrics, Clinical Science Departments 2010 - 2021
- Anderson-Rupp Professor, Biomedical Engineering, Pratt School of Engineering 2008 - 2013
- Associate Professor in Pediatrics, Pediatrics, Clinical Science Departments 1994 - 2003
- Chair, Biomedical Engineering, Pratt School of Engineering 1996 - 2000
- Interim Associate Dean, School of Engineering, Pratt School of Engineering, Duke University 1999
- Chair, Biomedical Engineering, Pratt School of Engineering 1995 - 1996
- Associate Professor, Pediatrics, Clinical Science Departments 1973 - 1995
- Associate Professor with Tenure, Biomedical Engineering, Pratt School of Engineering 1974 - 1979
- Associate Professor, Biomedical Engineering, Pratt School of Engineering 1972 - 1974
- Assistant Professor, Biomedical Engineering, Pratt School of Engineering 1969 - 1972
- Recognition
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In the News
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Awards & Honors
- Research
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Selected Grants
- Novel Methods for Cardiac Microimpedance Measurement awarded by University of Alabama at Birmingham 2009 - 2016
- Microscopic Discontinuities as a Basis for Arrhythmias awarded by National Institutes of Health 2000 - 2006
- Microscopic Discontinuities As A Basis For Arrhythmias awarded by National Institutes of Health 1993 - 2000
- Textbook Revision, Bioelectricity: A Quantitive Approach awarded by Lord Foundation of North Carolina 1997 - 1998
- Training of Cardiovascular Biomedical Engineers awarded by National Institutes of Health 1991 - 1996
- Training of Cardiovascular Biomedical Engineers awarded by National Institutes of Health 1991 - 1996
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External Relationships
- Green Hill Farm Inc
- Publications & Artistic Works
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Selected Publications
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Academic Articles
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Barr, Roger C. “Design of an Interactive Simulation Environment for Arrays of Cardiac Cells.” Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Annual International Conference 2018 (July 2018): 5466–69. https://doi.org/10.1109/embc.2018.8513586.Full Text
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Fricks, Rafael B., Henry Tseng, Marjorie Veihl, Kishor S. Trivedi, and Roger C. Barr. “Robust Prediction Of Treatment Times In Concurrent Patient Care.” Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Annual International Conference 2018 (July 2018): 5370–73. https://doi.org/10.1109/embc.2018.8513569.Full Text
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Waits, Charlotte Mae K., Roger C. Barr, and Andrew E. Pollard. “Sensor spacing affects the tissue impedance spectra of rabbit ventricular epicardium.” American Journal of Physiology. Heart and Circulatory Physiology 306, no. 12 (June 2014): H1660–68. https://doi.org/10.1152/ajpheart.00661.2013.Full Text
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Pollard, Andrew E., and Roger C. Barr. “A new approach for resolution of complex tissue impedance spectra in hearts.” Ieee Transactions on Bio Medical Engineering 60, no. 9 (September 2013): 2494–2503. https://doi.org/10.1109/tbme.2013.2258917.Full Text
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Pollard, Andrew E., and Roger C. Barr. “A biophysical model for cardiac microimpedance measurements.” American Journal of Physiology. Heart and Circulatory Physiology 298, no. 6 (June 2010): H1699–1709. https://doi.org/10.1152/ajpheart.01131.2009.Full Text
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Barr, Roger C., Loren W. Nolte, and Andrew E. Pollard. “Bayesian quantitative electrophysiology and its multiple applications in bioengineering.” Ieee Reviews in Biomedical Engineering 3 (January 2010): 155–68. https://doi.org/10.1109/rbme.2010.2089375.Full Text
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Pollard, A. E., and R. C. Barr. “A biophysical model for cardiac microimpedance (Submitted).” American Journal of Physiology, Heart, May 1, 2009.
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Barr, R. C., L. W. Nolte, and A. E. Pollard. “Bayesian analysis of fiber impedance measurements.” Conference Proceedings : ... Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Conference, December 1, 2007, 423–29.
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Plonsey, R., and R. C. Barr. “Bioelectricity: A quantitative approach.” Bioelectricity: A Quantitative Approach, December 1, 2007, 1–528. https://doi.org/10.1007/978-0-387-48865-3.Full Text
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Mossop, Brian J., Roger C. Barr, Joshua W. Henshaw, and Fan Yuan. “Electric fields around and within single cells during electroporation-a model study.” Annals of Biomedical Engineering 35, no. 7 (July 2007): 1264–75. https://doi.org/10.1007/s10439-007-9282-1.Full Text
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Spach, M. S., and R. C. Barr. “To the Editor-Response.” Heart Rhythm 4, no. 7 (July 1, 2007): 989–90. https://doi.org/10.1016/j.hrthm.2007.03.012.Full Text
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Johnson, Chad R., Roger C. Barr, and Stephen M. Klein. “A computer model of electrical stimulation of peripheral nerves in regional anesthesia.” Anesthesiology 106, no. 2 (February 2007): 323–30. https://doi.org/10.1097/00000542-200702000-00021.Full Text Link to Item
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Spach, Madison S., J Francis Heidlage, Paul C. Dolber, and Roger C. Barr. “Mechanism of origin of conduction disturbances in aging human atrial bundles: experimental and model study.” Heart Rhythm 4, no. 2 (February 2007): 175–85. https://doi.org/10.1016/j.hrthm.2006.10.023.Full Text Link to Item
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Barr, R. C., L. W. Nolte, and A. E. Pollard. “Bayesian analysis of fiber impedance measurements.” Conference Proceedings : ... Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Conference 2007 (2007): 423–29.
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Barr, Roger C., Loren W. Nolte, and Andrew E. Pollard. “Bayesian analysis of fiber impedance measurements.” Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Annual International Conference 2007 (January 2007): 423–29. https://doi.org/10.1109/iembs.2007.4352314.Full Text
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Mossop, Brian J., Roger C. Barr, Joshua W. Henshaw, David A. Zaharoff, and Fan Yuan. “Electric fields in tumors exposed to external voltage sources: implication for electric field-mediated drug and gene delivery.” Annals of Biomedical Engineering 34, no. 10 (October 2006): 1564–72. https://doi.org/10.1007/s10439-006-9151-3.Full Text
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Pollard, Andrew E., and Roger C. Barr. “Cardiac microimpedance measurement in two-dimensional models using multisite interstitial stimulation.” American Journal of Physiology. Heart and Circulatory Physiology 290, no. 5 (May 2006): H1976–87. https://doi.org/10.1152/ajpheart.01180.2005.Full Text
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Pollard, A. E., and R. C. Barr. “Multisite interstitial stimulation for cardiac micro-impedance measurements.” Conference Proceedings : ... Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Conference, 2006, 1572–75.
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Pollard, Andrew E., and Roger C. Barr. “Multisite interstitial stimulation for cardiac micro-impedance measurements.” Conference Proceedings : ... Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Annual Conference 2006 (January 2006): 1572–75. https://doi.org/10.1109/iembs.2006.260244.Full Text
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Adamson, Philip B., Roger C. Barr, David J. Callans, Peng-Sheng Chen, David A. Lathrop, Jonathan C. Makielski, Jeanne M. Nerbonne, et al. “The perplexing complexity of cardiac arrhythmias: beyond electrical remodeling.” Heart Rhythm 2, no. 6 (June 2005): 650–59. https://doi.org/10.1016/j.hrthm.2005.03.009.Full Text
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Pollard, Andrew E., William M. Smith, and Roger C. Barr. “Feasibility of cardiac microimpedance measurement using multisite interstitial stimulation.” American Journal of Physiology. Heart and Circulatory Physiology 287, no. 6 (December 2004): H2402–11. https://doi.org/10.1152/ajpheart.00289.2004.Full Text
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Barr, R. “The state of the society.” Ieee Engineering in Medicine and Biology Magazine 23, no. 6 (November 1, 2004): 6–7. https://doi.org/10.1109/MEMB.2004.1378619.Full Text
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Spach, Madison S., J Francis Heidlage, Roger C. Barr, and Paul C. Dolber. “Cell size and communication: role in structural and electrical development and remodeling of the heart.” Heart Rhythm 1, no. 4 (October 2004): 500–515. https://doi.org/10.1016/j.hrthm.2004.06.010.Full Text Link to Item
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Barr, Roger. “The Disney story.” Ieee Engineering in Medicine and Biology Magazine : The Quarterly Magazine of the Engineering in Medicine & Biology Society 23, no. 5 (September 2004): 6–7. https://doi.org/10.1109/memb.2004.1297165.Full Text
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Mossop, Brian J., Roger C. Barr, David A. Zaharoff, and Fan Yuan. “Electric fields within cells as a function of membrane resistivity--a model study.” Ieee Transactions on Nanobioscience 3, no. 3 (September 2004): 225–31. https://doi.org/10.1109/tnb.2004.833703.Full Text
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Barr, Roger. “Rich before old?” Ieee Engineering in Medicine and Biology Magazine : The Quarterly Magazine of the Engineering in Medicine & Biology Society 23, no. 4 (July 2004): 5–6. https://doi.org/10.1109/memb.2004.1337935.Full Text
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Barr, Roger. “The attention economy and the EMBS.” Ieee Engineering in Medicine and Biology Magazine : The Quarterly Magazine of the Engineering in Medicine & Biology Society 23, no. 3 (May 2004): 5–6.
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Barr, R. “EMBS international.” Ieee Engineering in Medicine and Biology Magazine 23, no. 2 (March 1, 2004): 6. https://doi.org/10.1109/MEMB.2004.1310959.Full Text
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Barr, Roger C., and Robert Plonsey. “Field stimulation of 2-D sheets of excitable tissue.” Ieee Transactions on Bio Medical Engineering 51, no. 3 (March 2004): 539–40. https://doi.org/10.1109/tbme.2003.821042.Full Text
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Barr, R. C., and C. R. Johnson. “A Possible EMB Award Recognizing Excellent Research by Graduate Students Published in EMB Journals.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 4 (December 1, 2003): 3474.
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Barr, R. C., and R. Plonsey. “Design of Electrode Systems for Measuring Cardiac Micro-Impedances Using Optical Sensors.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 4 (December 1, 2003): 3756–59.
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Johnson, Chad R., and Roger C. Barr. “Interactions between extracellular stimuli and excitation waves in an atrial reentrant loop.” Journal of Cardiovascular Electrophysiology 14, no. 10 (October 2003): 1064–74. https://doi.org/10.1046/j.1540-8167.2003.02443.x.Full Text
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Barr, Roger C., and Robert Plonsey. “Electrode systems for measuring cardiac impedances using optical transmembrane potential sensors and interstitial electrodes--theoretical design.” Ieee Transactions on Bio Medical Engineering 50, no. 8 (August 2003): 925–34. https://doi.org/10.1109/tbme.2003.814529.Full Text
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Barr, R. C., R. Plonsey, and C. R. Johnson. “Membrane current from transmembrane potentials in complex core-conductor models.” Ieee Trans. Biomed. Eng. (Usa) 50, no. 4 (2003): 405–11. https://doi.org/10.1109/TBME.2003.809508.Full Text Link to Item
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Zaharoff, D. A., R. C. Barr, C. -. Y. Li, and F. Yuan. “Electromobility of plasmid DNA in tumor tissues during electric field-mediated gene delivery.” Gene Ther 9, no. 19 (October 2002): 1286–90. https://doi.org/10.1038/sj.gt.3301799.Full Text Link to Item
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Johnson, C. R., and R. C. Barr. “Termination of reentrant propagation by a single extracellular stimulus in an atrial ring model.” Annual Reports of the Research Reactor Institute, Kyoto University 1 (December 1, 2001): 398–401.
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Smith, W. M., and R. C. Barr. “The forward and inverse problems: what are they, why are they important, and where do we stand?” Journal of Cardiovascular Electrophysiology 12, no. 2 (February 2001): 253–55. https://doi.org/10.1046/j.1540-8167.2001.00253.x.Full Text
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Spach, M. S., J. F. Heidlage, P. C. Dolber, and R. C. Barr. “Changes in anisotropic conduction caused by remodeling cell size and the cellular distribution of gap junctions and Na(+) channels.” J Electrocardiol 34 Suppl (2001): 69–76. https://doi.org/10.1054/jelc.2001.28833.Full Text Link to Item
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Zaharoff, D., R. Barr, C. Y. Li, and F. Yuan. “Mobility of plasmid DNA subject to pulsed electric fields.” Annals of Biomedical Engineering 28, no. SUPPL. 1 (December 1, 2000).
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Spach, M. S., J. F. Heidlage, P. C. Dolber, and R. C. Barr. “Electrophysiological effects of remodeling cardiac gap junctions and cell size: experimental and model studies of normal cardiac growth.” Circulation Research 86, no. 3 (February 2000): 302–11. https://doi.org/10.1161/01.res.86.3.302.Full Text
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Spach, M. S., J. F. Heidlage, P. C. Dolber, and R. C. Barr. “Extracellular discontinuities in cardiac muscle: evidence for capillary effects on the action potential foot.” Circulation Research 83, no. 11 (November 1998): 1144–64. https://doi.org/10.1161/01.res.83.11.1144.Full Text
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Plonsey, R., and R. C. Barr. “Electric field stimulation of excitable tissue.” Ieee Engineering in Medicine and Biology Magazine : The Quarterly Magazine of the Engineering in Medicine & Biology Society 17, no. 5 (September 1998): 130–37. https://doi.org/10.1109/51.715497.Full Text
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Barr, R. C., and R. Plonsey. “Subthreshold electric field stimulation of excitable tissue.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 6 (December 1, 1997): 2596–2600.
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Barr, R. C., and R. Plonsey. “Threshold estimation with field stimulation [transmembrane potentials].” Med. Biol. Eng. Comput. (Uk) 34 (1996): 21–24.
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Ideker, R. E., and R. C. Barr. “Special Issue on Electrical Therapy of Cardiac Arrhythmias.” Proceedings of the Ieee 84, no. 3 (January 1, 1996): 331. https://doi.org/10.1109/JPROC.1996.486737.Full Text
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Plonsey, R., and R. C. Barr. “Electric field stimulation of cardiac tissue.” Med. Biol. Eng. Comput. (Uk) 34 (1996): 25–28.
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Barr, R. C., and R. Plonsey. “Threshold variability in fibers with field stimulation of excitable membranes.” Ieee Transactions on Bio Medical Engineering 42, no. 12 (December 1995): 1185–91. https://doi.org/10.1109/10.476125.Full Text
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Barr, R. C., and R. Plonsey. “Repolarizing stimuli followed by calcium transmembrane currents.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 17, no. 1 (December 1, 1995): 15–16.
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Papazoglou, A. A., and R. C. Barr. “Sustained reentrant propagation in loops of decoupled cardiac cells.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 17, no. 1 (December 1, 1995): 23–24.
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Plonsey, R., and R. C. Barr. “Electric field stimulation of excitable tissue.” Ieee Transactions on Bio Medical Engineering 42, no. 4 (April 1995): 329–36. https://doi.org/10.1109/10.376126.Full Text
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Papazoglou, A. A., and R. C. Barr. “Model of sustained propagation in a 20-cell ring of Purkinje tissue.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 16, no. pt 2 (December 1, 1994): 1185.
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Ihara, T., and R. C. Barr. “Electrocardiographic inverse solution for ectopic origin of excitation in two-dimensional propagation model.” Medical & Biological Engineering & Computing 32, no. 4 Suppl (July 1994): S41–50. https://doi.org/10.1007/bf02523326.Full Text
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Papazoglou, A. A., and R. C. Barr. “Faster simulations of action potential propagation using the newton method.” Proceedings of the Annual Conference on Engineering in Medicine and Biology 15, no. pt 2 (December 1, 1993): 750–51.
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Cabo, C., and R. C. Barr. “Unidirectional block in a computer model of partially coupled segments of cardiac Purkinje tissue.” Annals of Biomedical Engineering 21, no. 6 (November 1993): 633–44. https://doi.org/10.1007/bf02368643.Full Text
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Cabo, C., and R. C. Barr. “Reflection after delayed excitation in a computer model of a single fiber.” Circulation Research 71, no. 2 (August 1992): 260–70. https://doi.org/10.1161/01.res.71.2.260.Full Text
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Barr, R. C., and R. Plonsey. “Electrophysiological interaction through the interstitial space between adjacent unmyelinated parallel fibers.” Biophysical Journal 61, no. 5 (May 1992): 1164–75. https://doi.org/10.1016/s0006-3495(92)81925-2.Full Text
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Cabo, C., and R. C. Barr. “Propagation model using the DiFrancesco-Noble equations. Comparison to reported experimental results.” Medical & Biological Engineering & Computing 30, no. 3 (May 1992): 292–302. https://doi.org/10.1007/bf02446967.Full Text
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Plonsey, R., and R. C. Barr. “A possible subcellular structure based on the macroscopic cardiac source.” Journal of Electrocardiology 25 Suppl (January 1992): 80–86. https://doi.org/10.1016/0022-0736(92)90066-9.Full Text
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Cabo, C., and R. C. Barr. “Refractory period in the DiFrancesco-Noble model for Purkinje fibers.” Proceedings of the Annual Conference on Engineering in Medicine and Biology 13, no. pt 2 (December 1, 1991): 523–24.
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Dabasinskas, A. J., and R. C. Barr. “Distinguishing ectopic sites in the canine heart by means of body surface waveforms.” Proceedings of the Annual Conference on Engineering in Medicine and Biology 13, no. pt 2 (December 1, 1991): 709–10.
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Pollard, A. E., and R. C. Barr. “Computer simulations of activation in an anatomically based model of the human ventricular conduction system.” Ieee Transactions on Bio Medical Engineering 38, no. 10 (October 1991): 982–96. https://doi.org/10.1109/10.88444.Full Text
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Plonsey, R., R. C. Barr, and F. X. Witkowski. “One-dimensional model of cardiac defibrillation.” Medical & Biological Engineering & Computing 29, no. 5 (September 1991): 465–69. https://doi.org/10.1007/bf02442315.Full Text
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Ihara, T., and R. C. Barr. “Inverse solutions of ECG using propagation model: A 2-D cross-sectional model.” Proceedings of the Annual Conference on Engineering in Medicine and Biology, no. pt 2 (December 1, 1990): 630–31.
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Krakow, W. T., B. Sacks, S. C. Roy, W. E. Batchelor, L. N. Bohs, and R. C. Barr. “Simulation and vertification of a chip architecture for electrocardiogram data compression.” Modeling and Simulation, Proceedings of the Annual Pittsburgh Conference 21, no. pt 4 (December 1, 1990): 1677–81.
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Pollard, A. E., and R. C. Barr. “The construction of an anatomically based model of the human ventricular conduction system.” Ieee Transactions on Bio Medical Engineering 37, no. 12 (December 1990): 1173–85. https://doi.org/10.1109/10.64460.Full Text
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Roy, S. C., W. T. Krakow, B. Sacks, W. E. Batchelor, L. N. Bohs, and R. C. Barr. “The design and verification of a VLSI chip for electrocardiogram data compression,” December 1, 1990, 170–77.
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Ihara, T., and R. C. Barr. “Transmembrane current model in a stylized form.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 11 pt 4 (December 1, 1989): 1263.
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Bohs, L. N., R. C. Barr, B. Sacks, and W. T. Krakow. “VLSI design for fan adaptive sampling.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 11 pt 1 (November 1, 1989): 18.
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Pollard, A. E., and R. C. Barr. “Computer simulations of excitation in an anatomically based model of the human ventricular conduction system.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings 11 pt 1 (November 1, 1989): 179–80.
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Bohs, L. N., and R. C. Barr. “Real-time adaptive sampling with the fan algorithm.” Medical & Biological Engineering & Computing 26, no. 6 (November 1988): 565–73. https://doi.org/10.1007/bf02447493.Full Text
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Bohs, L. N., and R. C. Barr. “Prototype for real-time adaptive sampling using the fan algorithm.” Medical & Biological Engineering & Computing 26, no. 6 (November 1988): 574–83. https://doi.org/10.1007/bf02447494.Full Text
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Bohs, L. N., and R. C. Barr. “Adaptive sampling using adaptive tolerance for mixed rate transmission.” Ieee/Engineering in Medicine and Biology Society Annual Conference 10, no. pt 1 (November 1, 1988): 20.
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Pollard, A. E., and R. C. Barr. “Automated construction of simulation models for a study of the electrical activity in the ventricular conduction system.” Ieee/Engineering in Medicine and Biology Society Annual Conference 10, no. pt 1 (November 1, 1988): 191–92.
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Barr, R. C. “Adaptive sampling of cardiac waveforms.” Journal of Electrocardiology 21 Suppl (January 1988): S57–60. https://doi.org/10.1016/0022-0736(88)90057-x.Full Text
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Barr, R. C., and D. A. DiPersio. “INVERSE PROBLEMS BASED ON MEMBRANE PROPAGATION MODELS.” Ieee/Engineering in Medicine and Biology Society Annual Conference, December 1, 1987, 559–60.
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Bohs, L. N., and R. C. Barr. “REAL-TIME ADAPTIVE SAMPLING WITH THE FAN METHOD.” Ieee/Engineering in Medicine and Biology Society Annual Conference, December 1, 1987, 1850–51.
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DiPersio, D. A., and R. C. Barr. “A prototype inverse solution in one-dimension to find the origin of excitation, strand radius, intracellular resistivity, or distance from the surface.” Ieee Transactions on Bio Medical Engineering 34, no. 9 (September 1987): 681–91. https://doi.org/10.1109/tbme.1987.325993.Full Text
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Plonsey, R., and R. C. Barr. “Mathematical modeling of electrical activity of the heart.” Journal of Electrocardiology 20, no. 3 (July 1987): 219–26. https://doi.org/10.1016/s0022-0736(87)80019-5.Full Text
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Pollard, A. E., and R. C. Barr. “Adaptive sampling of intracellular and extracellular cardiac potentials with the fan method.” Medical & Biological Engineering & Computing 25, no. 3 (May 1987): 261–68. https://doi.org/10.1007/bf02447422.Full Text
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Plonsey, R., and R. C. Barr. “Interstitial potentials and their change with depth into cardiac tissue.” Biophysical Journal 51, no. 4 (April 1987): 547–55. https://doi.org/10.1016/s0006-3495(87)83380-5.Full Text
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Spach, M. S., and R. C. Barr. “Body surface mapping for arrhythmias: Discussion.” Circulation 75, no. 4 II SUPPL. (1987): III-84-III–85.
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Spach, M. S., and R. C. Barr. “Body surface mapping for arrhythmias: Discussion.” Circulation 75, no. 4 II SUPPL. (January 1, 1987).
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Plonsey, R., and R. C. Barr. “Effect of microscopic and macroscopic discontinuities on the response of cardiac tissue to defibrillating (stimulating) currents.” Medical & Biological Engineering & Computing 24, no. 2 (March 1986): 130–36. https://doi.org/10.1007/bf02443925.Full Text
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Plonsey, R., and R. C. Barr. “Inclusion of junction elements in a linear cardiac model through secondary sources: application to defibrillation.” Medical & Biological Engineering & Computing 24, no. 2 (March 1986): 137–44. https://doi.org/10.1007/bf02443926.Full Text
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DiPersio, D. A., and R. C. Barr. “INVERSE SOLUTION IN ONE DIMENSION USING A MEMBRANE MODEL.,” January 1, 1986, 225–28.
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Plonsey, R., and R. C. Barr. “A critique of impedance measurements in cardiac tissue.” Annals of Biomedical Engineering 14, no. 4 (January 1986): 307–22. https://doi.org/10.1007/bf02367405.Full Text
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Plonsey, R., and R. C. Barr. “IMPEDANCE MEASUREMENTS IN CARDIAC TISSUE.” Bioengineering, Proceedings of the Northeast Conference, December 1, 1985, 41–44.
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DiPersio, D. A., and R. C. Barr. “Evaluation of the fan method of adaptive sampling on human electrocardiograms.” Medical & Biological Engineering & Computing 23, no. 5 (September 1985): 401–10. https://doi.org/10.1007/bf02448926.Full Text
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Blanchard, S. M., and R. C. Barr. “Comparison of methods for adaptive sampling of cardiac electrograms and electrocardiograms.” Medical & Biological Engineering & Computing 23, no. 4 (July 1985): 377–86. https://doi.org/10.1007/bf02441592.Full Text
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Barr, R. C., S. M. Blanchard, and D. A. Dipersio. “SAPA-2 is the Fan.” Ieee Transactions on Bio Medical Engineering 32, no. 5 (May 1985): 337. https://doi.org/10.1109/tbme.1985.325548.Full Text
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Barr, R. C., S. M. Blanchard, and D. A. Dipersio. “SAPA-2 is the Fan [ECG].” Ieee Trans. Biomed. Eng. (Usa) BME-32, no. 5 (1985): 337.
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Plonsey, R., and R. C. Barr. “Effect of junctional resistance on source-strength in a linear cable.” Annals of Biomedical Engineering 13, no. 1 (January 1985): 95–100. https://doi.org/10.1007/bf02371252.Full Text
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Barr, R. C., and S. M. Blanchard. “COMPARISON OF ADAPTIVE SAMPLING METHODS FOR ELECTROGRAMS AND ELECTROCARDIOGRAMS.” Ieee/Engineering in Medicine and Biology Society Annual Conference, December 1, 1984, 220–23.
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Carollo, J. J., R. C. Barr, and J. D. Thelen. “MOTORIZED FOREARM MODULE FOR PROSTHETIC TERMINAL DEVICES.” Ieee/Engineering in Medicine and Biology Society Annual Conference, December 1, 1984, 43–46.
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DiPersio, D. A., and R. C. Barr. “STUDY OF THE FAN METHOD OF ADAPTIVE SAMPLING FOR HUMAN ECGS.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings, December 1, 1984, 315.
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Barr, R. C. “Finding the site of origin and velocity of propagation in a short one-dimensional strand from two extracellular waveforms.” Ieee Transactions on Bio Medical Engineering 31, no. 8 (August 1984): 546–50. https://doi.org/10.1109/tbme.1984.325423.Full Text
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Barr, R. C., and R. Plonsey. “Propagation of excitation in idealized anisotropic two-dimensional tissue.” Biophysical Journal 45, no. 6 (June 1984): 1191–1202. https://doi.org/10.1016/s0006-3495(84)84268-x.Full Text
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Plonsey, R., and R. C. Barr. “Current flow patterns in two-dimensional anisotropic bisyncytia with normal and extreme conductivities.” Biophysical Journal 45, no. 3 (March 1984): 557–71. https://doi.org/10.1016/s0006-3495(84)84193-4.Full Text
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Barr, R. C. “Finding the site of origin and velocity of propagation in a short one-dimensional strand from two extracellular waveforms.” Ieee Trans. Biomed. Eng. (Usa) BME-31, no. 8 (1984): 546–50.
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Barr, R. C., and M. S. Spach. “Construction and interpretation of body surface maps.” Progress in Cardiovascular Diseases 26, no. 1 (July 1983): 33–42. https://doi.org/10.1016/0033-0620(83)90017-8.Full Text
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Spach, M. S., and R. C. Barr. “Localizing cardiac electrical events from body surface maps.” International Journal of Cardiology 3, no. 4 (July 1983): 459–64. https://doi.org/10.1016/0167-5273(83)90119-5.Full Text
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Blanchard, S. M., and R. C. Barr. “ZERO, FIRST, AND SECOND ORDER ADAPTIVE SAMPLING FROM ECGS.” Annual International Conference of the Ieee Engineering in Medicine and Biology Proceedings, December 1, 1982, 209.
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Blanchard, S. M., R. C. Barr, and M. S. Spach. “A voltage-triggered system for adaptive sampling in body surface mapping.” Ieee Transactions on Bio Medical Engineering 29, no. 11 (November 1982): 726–30. https://doi.org/10.1109/tbme.1982.325003.Full Text
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Geselowitz, D. B., R. C. Barr, M. S. Spach, and W. T. Miller. “The impact of adjacent isotropic fluids on electrograms from anisotropic cardiac muscle. A modeling study.” Circulation Research 51, no. 5 (November 1982): 602–13. https://doi.org/10.1161/01.res.51.5.602.Full Text
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Plonsey, R., and R. Barr. “The four-electrode resistivity technique as applied to cardiac muscle.” Ieee Transactions on Bio Medical Engineering 29, no. 7 (July 1982): 541–46. https://doi.org/10.1109/tbme.1982.324927.Full Text
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Blanchard, S. M., R. C. Barr, and M. S. Spach. “A voltage-triggered system for adaptive sampling in body surface mapping.” Ieee Trans. Biomed. Eng. (Usa) BME-29, no. 11 (1982): 726–30.
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Plonsey, R., and R. C. Barr. “The four-electrode resistivity technique as applied to cardiac muscle.” Japanese Heart Journal 23, no. Suppl. 1 (January 1, 1982): 23–25.
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Spach, M. S., R. C. Barr, and D. W. Benson. “A portable body surface potential mapping system.” Japanese Heart Journal 23, no. Suppl. 1 (January 1, 1982): 330–32.
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Spach, M. S., W. T. Miller, D. B. Geselowitz, R. C. Barr, J. M. Kootsey, and E. A. Johnson. “The discontinuous nature of propagation in normal canine cardiac muscle. Evidence for recurrent discontinuities of intracellular resistance that affect the membrane currents.” Circulation Research 48, no. 1 (January 1981): 39–54. https://doi.org/10.1161/01.res.48.1.39.Full Text
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Barr, R. C., T. M. Gallie, and M. S. Spach. “Automated production of contour maps for electrophysiology. I. Problem definition, solution strategy, and specification of geometric model.” Computers and Biomedical Research, an International Journal 13, no. 2 (April 1980): 142–53. https://doi.org/10.1016/0010-4809(80)90013-0.Full Text
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Barr, R. C., T. M. Gallie, and M. S. Spach. “Automated production of contour maps for electrophysiology. II. Triangulation, verification, and organization of the geometric model.” Computers and Biomedical Research, an International Journal 13, no. 2 (April 1980): 154–70. https://doi.org/10.1016/0010-4809(80)90014-2.Full Text
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Barr, R. C., T. M. Gallie, and M. S. Spach. “Automated production of contour maps for electrophysiology. III. Construction of contour maps.” Computers and Biomedical Research, an International Journal 13, no. 2 (April 1980): 171–91. https://doi.org/10.1016/0010-4809(80)90015-4.Full Text
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Geselowitz, D. B., R. C. Arzbaecher, R. C. Barr, S. A. Briller, A. N. Damato, N. Flowers, K. Millar, G. C. Oliver, R. Plonsey, and R. E. Smith. “Electrical safety standards for electrocardiographic apparatus.” Circulation 61, no. 4 (April 1980): 669–70. https://doi.org/10.1161/01.cir.61.4.669.Full Text
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Barr, R. C., T. M. Gallie, and M. S. Spach. “CONSTRUCTION OF ISOCHRONE OR ISOPOTENTIAL MAPS FOR CARDIAC ELECTROPHYSIOLOGY - A STATEMENT OF THE PROBLEM AND ONE APPROACH TO ITS SOLUTION.” Multi Phase Transport: Fundamentals, Reactor Safety, Applications, January 1, 1980, 13–18.
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Barr, R. C., T. M. Gallie, and M. S. Spach. “CONSTRUCTION OF ISOCHRONE OR ISOPOTENTIAL MAPS FOR CARDIAC ELECTROPHYSIOLOGY - A STATEMENT OF THE PROBLEM AND ONE APPROACH TO ITS SOLUTION.” Multi Phase Transport: Fundamentals, Reactor Safety, Applications, 1980, 13–18.
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Benson, D. W., J. J. Gallagher, M. S. Spach, R. C. Barr, S. B. Edwards, H. N. Oldham, and J. Kasell. “Accessory atrioventricular pathway in an infant: prediction of location with body surface maps and ablation with cryosurgery.” J Pediatr 96, no. 1 (January 1980): 41–46. https://doi.org/10.1016/s0022-3476(80)80321-0.Full Text Link to Item
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Spach, M. S., W. T. Miller, E. Miller-Jones, R. B. Warren, and R. C. Barr. “Extracellular potentials related to intracellular action potentials during impulse conduction in anisotropic canine cardiac muscle.” Circulation Research 45, no. 2 (August 1979): 188–204. https://doi.org/10.1161/01.res.45.2.188.Full Text
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Spach, M. S., R. C. Barr, R. B. Warren, D. W. Benson, A. Walston, and S. B. Edwards. “Isopotential body surface mapping in subjects of all ages: emphasis on low-level potentials with analysis of the method.” Circulation 59, no. 4 (April 1979): 805–21. https://doi.org/10.1161/01.cir.59.4.805.Full Text
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Spach, M. S., R. C. Barr, W. Benson, A. Walston, R. B. Warren, and S. B. Edwards. “Body surface low-level potentials during ventricular repolarization with analysis of the ST segment: variability in normal subjects.” Circulation 59, no. 4 (April 1979): 822–36. https://doi.org/10.1161/01.cir.59.4.822.Full Text
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Hersh, L. T., R. C. Barr, and M. S. Spach. “An analysis of transfer coefficients calculated directly from epicardial and body surface potential measurements in the intact dog.” Ieee Transactions on Bio Medical Engineering 25, no. 5 (September 1978): 446–61. https://doi.org/10.1109/tbme.1978.326351.Full Text
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Barr, R. C., and M. S. Spach. “Inverse calculation of QRS-T epicardial potentials from body surface potential distributions for normal and ectopic beats in the intact dog.” Circulation Research 42, no. 5 (May 1978): 661–75. https://doi.org/10.1161/01.res.42.5.661.Full Text
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Barr, R. C., and M. S. Spach. “A comparison of measured epicardial potentials with epicardial potentials computed from body surface measurements in the intact dog.” Advances in Cardiology 21 (January 1978): 19–22. https://doi.org/10.1159/000400413.Full Text
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Spach, M. S., R. C. Barr, and C. F. Lanning. “Experimental basis for QRS and T wave potentials in the WPW syndrome. The relation of epicardial to body surface potential distributions in the intact chimpanzee.” Circulation Research 42, no. 1 (January 1978): 103–18. https://doi.org/10.1161/01.res.42.1.103.Full Text
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Spach, M. S., and R. C. Barr. “Origin of epicardial ST-T wave potentials in the intact dog.” Advances in Cardiology 21 (January 1978): 15–18. https://doi.org/10.1159/000400412.Full Text
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Ramsey, M., R. C. Barr, and M. S. Spach. “Comparison of measured torso potentials with those simulated from epicardial potentials for ventricular depolarization and repolarization in the intact dog.” Circulation Research 41, no. 5 (November 1977): 660–72. https://doi.org/10.1161/01.res.41.5.660.Full Text
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Spach, M. S., R. C. Barr, C. F. Lanning, and P. C. Tucek. “Origin of body surface QRS and T wave potentials from epicardial potential distributions in the intact chimpanzee.” Circulation 55, no. 2 (February 1977): 268–268. https://doi.org/10.1161/01.cir.55.2.268.Full Text
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Barr, R. C., M. Ramsey, and M. S. Spach. “Relating epicardial to body surface potential distributions by means of transfer coefficients based on geometry measurements.” Ieee Transactions on Bio Medical Engineering 24, no. 1 (January 1977): 1–11. https://doi.org/10.1109/tbme.1977.326201.Full Text
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Barr, R. C., Ramsey M. III, and M. S. Spach. “Relating epicardial to body surface potential distributions by means of transfer coefficients based on geometry measurements.” Ieee Trans. Biomed. Eng. (Usa) BME-24, no. 1 (1977): 1–11.
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Barr, R. C., and M. S. Spach. “Sampling rates required for digital recording of intracellular and extracellular cardiac potentials.” Circulation 55, no. 1 (January 1977): 40–48. https://doi.org/10.1161/01.cir.55.1.40.Full Text
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Barr, R., B. M. Horacek, and H. J. Ritsema. “Direct and inverse solutions; equivalent cardiac generator models.” Advances in Cardiology Vol. 21 (January 1, 1977): 110–14.
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Taccardi, B., R. Barr, and F. Kornreich. “Surface maps; information content and data reduction; lead systems.” Advances in Cardiology Vol. 21 (January 1, 1977): 115–20.
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Barr, R. C., G. S. Herman-Giddens, M. S. Spach, R. B. Warren, and T. M. Gallie. “The design of a real-time computer system for examining the electrical activity of the heart.” Computers and Biomedical Research, an International Journal 9, no. 5 (October 1976): 445–69. https://doi.org/10.1016/0010-4809(76)90061-6.Full Text
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Spach, M. S., and R. C. Barr. “Origin of epicardial ST-T wave potentials in the intact dog.” Circulation Research 39, no. 4 (October 1976): 475–87. https://doi.org/10.1161/01.res.39.4.475.Full Text
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Spach, M. S., and R. C. Barr. “Anaylsis of ventricular activation and repolarization from intramural and epicardial potential distributions for ectopic beats in the intact dog.” Circulation Research 37, no. 6 (December 1975): 830–43. https://doi.org/10.1161/01.res.37.6.830.Full Text
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Spach, M. S., and R. C. Barr. “Ventricular intramural and epicardial potential distributions during ventricular activation and repolarization in the intact dog.” Circulation Research 37, no. 2 (August 1975): 243–57. https://doi.org/10.1161/01.res.37.2.243.Full Text
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Barr, R. C., M. S. Spach, L. T. Hersh, and M. Ramsey. “Inverse calculation of QRS T epicardial potentials from body surface maps for normal and ectopic beats in the intact dog.” Circulation 52, no. 4 sup 2 (January 1, 1975).
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Herman‐Giddens, G. S., R. B. Warren, R. C. Barr, and M. S. Spach. “Biomac: Block structured programming using PDP‐11 assembler language.” Software: Practice and Experience 5, no. 4 (January 1, 1975): 359–74. https://doi.org/10.1002/spe.4380050406.Full Text
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Spach, M. S., and R. C. Barr. “A test of the 'SI' theory of repolarization potentials in complex excitation sequences in the intact dog.” Circulation 52, no. 4 sup 2 (January 1, 1975).
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Spach, M. S., R. C. Barr, E. A. Johnson, and J. M. Kootsey. “Cardiac extracellular potentials. Analysis of complex wave forms about the Purkinje networks in dogs.” Circulation Research 33, no. 4 (October 1973): 465–73. https://doi.org/10.1161/01.res.33.4.465.Full Text
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Spach, M. S., R. C. Barr, and P. H. Jewett. “Spread of excitation from the atrium into thoracic veins in human beings and dogs.” The American Journal of Cardiology 30, no. 8 (December 1972): 844–54. https://doi.org/10.1016/0002-9149(72)90009-4.Full Text
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Spach, M. S., and R. C. Barr. “The use of isopotential surface maps in understanding clinical ECGs.” American Journal of Diseases of Children (1960) 124, no. 3 (September 1972): 359–63. https://doi.org/10.1001/archpedi.1972.02110150057010.Full Text
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Spach, M. S., R. C. Barr, G. A. Serwer, J. M. Kootsey, and E. A. Johnson. “Extracellular potentials related to intracellular action potentials in the dog Purkinje system.” Circulation Research 30, no. 5 (May 1972): 505–19. https://doi.org/10.1161/01.res.30.5.505.Full Text
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King, T. D., R. C. Barr, G. S. Herman-Giddens, D. E. Boaz, and M. S. Spach. “Isopotential body surface maps and their relationship to atrial potentials in the dog.” Circulation Research 30, no. 4 (April 1972): 393–405. https://doi.org/10.1161/01.res.30.4.393.Full Text
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Blumenschein, S. D., R. C. Barr, M. S. Spach, and R. C. Gentzler. “Quantitative Frank vectorcardiograms of normal children and a comparison to those of patients with atrial defects.” American Heart Journal 83, no. 3 (March 1972): 332–39. https://doi.org/10.1016/0002-8703(72)90434-6.Full Text
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Spach, M. S., R. C. Barr, G. S. Serwer, E. A. Johnson, and J. M. Kootsey. “Collision of excitation waves in the dog Purkinje system. Extracellular identification.” Circulation Research 29, no. 5 (November 1971): 499–511. https://doi.org/10.1161/01.res.29.5.499.Full Text
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Spach, M. S., M. Lieberman, J. G. Scott, R. C. Barr, E. A. Johnson, and J. M. Kootsey. “Excitation sequences of the atrial septum and the AV node in isolated hearts of the dog and rabbit.” Circulation Research 29, no. 2 (August 1971): 156–72. https://doi.org/10.1161/01.res.29.2.156.Full Text
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Barr, R. C., M. S. Spach, and G. S. Herman-Giddens. “Selection of the number and positions of measuring locations for electrocardiography.” Ieee Transactions on Bio Medical Engineering 18, no. 2 (March 1971): 125–38. https://doi.org/10.1109/tbme.1971.4502813.Full Text
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Karsh, R. B., M. S. Spach, and R. C. Barr. “Interpretation of isopotential surface maps in patients with Ostium Primum and Secundum atrial defects.” Circulation 41, no. 6 (June 1970): 913–33. https://doi.org/10.1161/01.cir.41.6.913.Full Text
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Barr, R. C., T. C. Pilkington, J. P. Boineau, and C. L. Rogers. “An inverse electrocardiographic solution with an ON-OFF model.” Ieee Transactions on Bio Medical Engineering 17, no. 1 (January 1970): 49–57. https://doi.org/10.1109/tbme.1970.4502684.Full Text
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Blumenschein, S. D., M. S. Spach, J. T. Flaherty, J. P. Boineau, R. C. Barr, and T. M. Gallie. “Exploratory electrocardiography: use of isopotential surface maps.” Ucla Forum in Medical Sciences 10 (January 1970): 347–68.
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Levin, A. R., M. M. Jarmakani, M. S. Spach, R. Canent RVJ, M. P. Capp, J. P. Boineau, and R. C. Barr. “Ventricular intracradiac shunting mechanisms in congenital heart disease.” Ucla Forum in Medical Sciences 10 (January 1970): 247–63.
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Barr, R. C., and T. C. Pilkington. “Computing inverse solutions for an on-off heart model.” Ieee Transactions on Bio Medical Engineering 16, no. 3 (July 1969): 205–14.
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Spach, M. S., T. D. King, R. C. Barr, D. E. Boaz, M. N. Morrow, and S. Herman-Giddens. “Electrical potential distribution surrounding the atria during depolarization and repolarization in the dog.” Circulation Research 24, no. 6 (June 1969): 857–73. https://doi.org/10.1161/01.res.24.6.857.Full Text
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Spach, M., R. Barr, S. Blumenschein, and J. Boineau. “Isopotential surface maps.” Annals of Internal Medicine 70, no. 5 (May 1969): 1048. https://doi.org/10.7326/0003-4819-70-5-1048.Full Text
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Pilkington, T. C., R. C. Barr, and C. L. Rogers. “Effect of conductivity interfaces in electrocardiography.” The Bulletin of Mathematical Biophysics 30, no. 4 (December 1968): 637–43. https://doi.org/10.1007/bf02476680.Full Text
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Blumenschein, S. D., M. S. Spach, J. P. Boineau, R. C. Barr, T. M. Gallie, A. G. Wallace, and P. A. Ebert. “Genesis of body surface potentials in varying types of right ventricular hypertrophy.” Circulation 38, no. 5 (November 1968): 917–32. https://doi.org/10.1161/01.cir.38.5.917.Full Text
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Spach, M. S., R. C. Barr, S. D. Blumenschein, and J. P. Boineau. “Clinical implications of isopotential surface maps.” Annals of Internal Medicine 69, no. 5 (November 1968): 919–28. https://doi.org/10.7326/0003-4819-69-5-919.Full Text
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Jarmakani, M. M., S. B. Edwards, M. S. Spach, R. V. Canent, M. P. Capp, M. J. Hagan, R. C. Barr, and V. Jain. “Left ventricular pressure-volume characteristics in congenital heart disease.” Circulation 37, no. 6 (June 1968): 879–89. https://doi.org/10.1161/01.cir.37.6.879.Full Text
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Pilkington, T. C., R. C. Barr, and C. L. Rogers. “Effect of conductivity interfaces.” The Bulletin of Mathematical Biophysics 29, no. 4 (December 1967): 705–10. https://doi.org/10.1007/bf02476921.Full Text
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Flaherty, J. T., M. S. Spach, J. P. Boineau, R. V. Canent, R. C. Barr, and D. C. Sabiston. “Cardiac potentials on body surface of infants with anomalous left coronary artery (myocardial infarction).” Circulation 36, no. 3 (September 1967): 345–58. https://doi.org/10.1161/01.cir.36.3.345.Full Text
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Barr, R. C., M. S. Spach, J. P. Boineau, and T. C. Pilkington. “Letter to the editor.” American Heart Journal 74, no. 2 (August 1, 1967): 293–293.Link to Item
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Levin, A. R., M. S. Spach, R. V. Canent, J. P. Boineau, M. P. Capp, V. Jain, and R. C. Barr. “Intracardiac pressure-flow dynamics in isolated ventricular septal defects.” Circulation 35, no. 3 (March 1967): 430–41. https://doi.org/10.1161/01.cir.35.3.430.Full Text
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Spach, M. S., W. P. Silberberg, J. P. Boineau, R. C. Barr, E. C. Long, T. M. Gallie, J. B. Gabor, and A. G. Wallace. “Body surface isopotential maps in normal children, ages 4 to 14 years.” American Heart Journal 72, no. 5 (November 1966): 640–52. https://doi.org/10.1016/0002-8703(66)90347-4.Full Text
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Barr, R. C., T. C. Pilkington, J. P. Boineau, and M. S. Spach. “Comparing methods of generating surface potentials.” Ieee Transactions on Bio Medical Engineering 13, no. 4 (October 1966): 210–11.
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Spach, M. S., R. C. Barr, J. W. Havstad, and E. C. Long. “Skin-electrode impedance and its effect on recording cardiac potentials.” Circulation 34, no. 4 (October 1966): 649–56. https://doi.org/10.1161/01.cir.34.4.649.Full Text
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Boineau, J. P., M. S. Spach, T. C. Pilkington, and R. C. Barr. “Relationship between body surface potential and ventricular excitation in the dog.” Circulation Research 19, no. 3 (September 1966): 489–95. https://doi.org/10.1161/01.res.19.3.489.Full Text
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Barr, R. C., T. C. Pilkington, J. P. Boineau, and M. S. Spach. “Determining surface potentials from current dipoles, with application to electrocardiography.” Ieee Transactions on Bio Medical Engineering 13, no. 2 (April 1966): 88–92. https://doi.org/10.1109/tbme.1966.4502411.Full Text
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Barr, R. C., T. C. Pilkington, J. P. Boineau, and M. S. Spach. “Determining surface potentials from current dipoles, with application to electrocardiography.” Ieee Transactions on Biomedical Engineering BME-13, no. 2 (1966): 88–92.
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Barr, R. C., T. C. Pilkington, J. P. Boineau, and M. S. Spach. “Comparing methods of generating surface potentials.” Ieee Transactions on Biomedical Engineering BME-13, no. 4 (1966): 210–11.
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Pilkington, T. C., W. C. Metz, and R. C. Barr. “Calculation of resistance of threedimensional configurations.” Proceedings of the Ieee 54, no. 2 (1966): 307.
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Hersh, L. T., R. C. Barr, and M. S. Spach. “An analysis of transfer coefficients calculated directly from epicardial and body surface potential measurements in the intact dog.” Ieee Trans. Biomed. Eng. (Usa) BME-25, no. 5 (n.d.): 446–61.
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Book Sections
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White, J. A., A. D. Dorval, L. A. Geddes, R. C. Barr, B. K. Slaten, F. Barnes, D. R. Martinez, R. A. Bond, and M. Michael Vai. “Bioelectricity.” In Sensors, Nanoscience, Biomedical Engineering, and Instruments, 2016.
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Barr, R. C. “Basic Electrophysiology.” In Biomedical Engineering Fundamentals, 38-1-38–21, 2014. https://doi.org/10.1201/b15482-43.Full Text
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Conference Papers
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Barr, Roger C. “Bioelectricity-AQA, one of the first MOOC courses in engineering.” In Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Annual International Conference, 2014:1805–8, 2014. https://doi.org/10.1109/embc.2014.6943959.Full Text
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Pollard, Andrew E., and Roger C. Barr. “A structural framework for interpretation of four-electrode microimpedance spectra in cardiac tissue.” In Annual International Conference of the Ieee Engineering in Medicine and Biology Society. Ieee Engineering in Medicine and Biology Society. Annual International Conference, 2014:6467–70, 2014. https://doi.org/10.1109/embc.2014.6945109.Full Text
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Barr, R. C., and R. Plonsey. “Propagation under the influence of interstitial potentials.” In Proceedings of the Annual International Conference of the Ieee Engineering in Medicine and Biology Society, Embs, 2:598–99, 1992. https://doi.org/10.1109/IEMBS.1992.5761129.Full Text
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Cabo, C., A. A. Papazoglou, and R. C. Barr. “Implementation, performance and characterization of the DiFrancesco-Noble model.” In Proceedings Computers in Cardiology, Cic 1992, 595–98, 1992. https://doi.org/10.1109/CIC.1992.269546.Full Text
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Barr, R. C., G. S. Herman-Giddens, R. B. Warren, and M. S. Spach. “Two-level control of a real-time data acquisition and control system for studying the electrical activity of the heart.” In Proceedings of the 16th Annual Southeast Regional Conference, Acm Se 1978, 288–94, 1978. https://doi.org/10.1145/503643.503706.Full Text
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Barr, R. C., G. S. Herman-Glddens, M. S. Spach, R. B. Warren, M. N. Morrow, and T. M. Gallie. “Organization of a computer system for measuring the electrical activity of the heart.” In Proceedings of the 14th Annual Southeast Regional Conference, Acm Se 1976, 380–86, 1976. https://doi.org/10.1145/503561.503641.Full Text
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