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Journal articles on the topic 'Spread of Excitation'

Author: Grafiati

Published: 28 September 2022

Last updated: 28 January 2023

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1

FRANZONE, PIERO COLLI, LUCIANO GUERRI, and BRUNO TACCARDI. "Spread of Excitation in a Myocardial Volume:." Journal of Cardiovascular Electrophysiology 4, no. 2 (April 1993): 144–60. http://dx.doi.org/10.1111/j.1540-8167.1993.tb01219.x.

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2

Arisi, Giorgio, Bruno Taccardi, and Emilio Macchi. "Epicardial spread of excitation during ventricular pacing." Journal of Electrocardiology 25, no. 3 (July 1992): 250–51. http://dx.doi.org/10.1016/0022-0736(92)90029-y.

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3

Chen, Nan Guang, and Quing Zhu. "Time-resolved optical measurements with spread spectrum excitation." Optics Letters 27, no. 20 (October 15, 2002): 1806. http://dx.doi.org/10.1364/ol.27.001806.

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4

Taccardi, B., Robert Lux, Philip Ershler, Shinji Watabe, and Emilio Macchi. "Intramural spread of excitation wavefronts and associated potential fields." Journal of Electrocardiology 23, no. 3 (July 1990): 282. http://dx.doi.org/10.1016/0022-0736(90)90191-4.

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5

Rocha, B. M., F. O. Campos, R. M. Amorim, G. Plank, R. W. dos Santos, M. Liebmann, and G. Haase. "Accelerating cardiac excitation spread simulations using graphics processing units." Concurrency and Computation: Practice and Experience 23, no. 7 (December 7, 2010): 708–20. http://dx.doi.org/10.1002/cpe.1683.

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6

Pal, Suvajit, and Manas Ghosh. "Influence of Oscillatory Impurity Potential and Concurrent Gasping of Impurity Spread on Excitation Profile of Doped Quantum Dots." Journal of Materials 2013 (February 21, 2013): 1–7. http://dx.doi.org/10.1155/2013/795450.

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Excitation in quantum dots is an important phenomenon. Realizing the importance we investigate the excitation behavior of a repulsive impurity-doped quantum dot induced by simultaneous oscillations of impurity potential and spatial stretch of impurity domain. The impurity potential has been assumed to have a Gaussian nature. The ratio of two oscillations (η) has been exploited to understand the nature of excitation rate. Indeed it has been found that the said ratio could fabricate the excitation in a remarkable way. The present study also indicates attainment of stabilization in the excitation rate as soon as η surpasses a threshold value regardless of the dopant location. However, within the stabilization zone we also observe maximization in the excitation rate at some typical location of dopant incorporation. The critical analysis of pertinent impurity parameters provides important perception about the physics behind the excitation process.

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7

Moore, Brian C. J., and Deborah A. Vickers. "The role of spread excitation and suppression in simultaneous masking." Journal of the Acoustical Society of America 102, no. 4 (October 1997): 2284–90. http://dx.doi.org/10.1121/1.419638.

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8

Bingabr, Mohamed, Blas Espinoza-Varas, and Philipos C. Loizou. "Simulating the effect of spread of excitation in cochlear implants." Hearing Research 241, no. 1-2 (July 2008): 73–79. http://dx.doi.org/10.1016/j.heares.2008.04.012.

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9

Hughes, Michelle L., Lisa J. Stille, Jacquelyn L. Baudhuin, and Jenny L. Goehring. "ECAP spread of excitation with virtual channels and physical electrodes." Hearing Research 306 (December 2013): 93–103. http://dx.doi.org/10.1016/j.heares.2013.09.014.

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10

Van Dijk, P., S. Van Weert, MMJG Rikers, and RJ Stokroos. "The effect of modiolus hugging on spread of neural excitation." Cochlear Implants International 6, sup1 (September 2005): 3–5. http://dx.doi.org/10.1179/cim.2005.6.supplement-1.3.

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11

Sellon, Jonathan B., Shirin Farrahi, Roozbeh Ghaffari, and Dennis M. Freeman. "Longitudinal spread of mechanical excitation through tectorial membrane traveling waves." Proceedings of the National Academy of Sciences 112, no. 42 (October 5, 2015): 12968–73. http://dx.doi.org/10.1073/pnas.1511620112.

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The mammalian inner ear separates sounds by their frequency content, and this separation underlies important properties of human hearing, including our ability to understand speech in noisy environments. Studies of genetic disorders of hearing have demonstrated a link between frequency selectivity and wave properties of the tectorial membrane (TM). To understand these wave properties better, we developed chemical manipulations that systematically and reversibly alter TM stiffness and viscosity. Using microfabricated shear probes, we show that (i) reducing pH reduces TM stiffness with little change in TM viscosity and (ii) adding PEG increases TM viscosity with little change in TM stiffness. By applying these manipulations in measurements of TM waves, we show that TM wave speed is determined primarily by stiffness at low frequencies and by viscosity at high frequencies. Both TM viscosity and stiffness affect the longitudinal spread of mechanical excitation through the TM over a broad range of frequencies. Increasing TM viscosity or decreasing stiffness reduces longitudinal spread of mechanical excitation, thereby coupling a smaller range of best frequencies and sharpening tuning. In contrast, increasing viscous loss or decreasing stiffness would tend to broaden tuning in resonance-based TM models. Thus, TM wave and resonance mechanisms are fundamentally different in the way they control frequency selectivity.

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12

Van Dijk, P., S. Van Weert, MMJG Rikers, and RJ Stokroos. "The effect of modiolus hugging on spread of neural excitation." Cochlear Implants International 6, S1 (September 2005): 3–5. http://dx.doi.org/10.1002/cii.269.

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13

Sellon, Jonathan B., Roozbeh Ghaffari, Shirin Farrahi, Guy P. Richardson, and Dennis M. Freeman. "Porosity Controls Spread of Excitation in Tectorial Membrane Traveling Waves." Biophysical Journal 106, no. 6 (March 2014): 1406–13. http://dx.doi.org/10.1016/j.bpj.2014.02.012.

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14

Sakai, Tetsuro. "Optical mapping of the spread of excitation in the isolated rat atrium during tachycardia-like excitation." Pfl�gers Archiv European Journal of Physiology 447, no. 3 (December 1, 2003): 280–88. http://dx.doi.org/10.1007/s00424-003-1185-x.

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15

Carlyon, Robert P. "Spread of excitation produced by maskers with damped and ramped envelopes." Journal of the Acoustical Society of America 99, no. 6 (June 1996): 3647–55. http://dx.doi.org/10.1121/1.414963.

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16

Biesheuvel, Jan Dirk, Jeroen J. Briaire, and Johan H. M. Frijns. "A Novel Algorithm to Derive Spread of Excitation Based on Deconvolution." Ear and Hearing 37, no. 5 (2016): 572–81. http://dx.doi.org/10.1097/aud.0000000000000296.

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17

Grolman, Wilko, Albert Maat, Froukje Verdam, Yvonne Simis, Bart Carelsen, Nicole Freling, and Rinze A. Tange. "Spread of Excitation Measurements for the Detection of Electrode Array Foldovers." Otology & Neurotology 30, no. 1 (January 2009): 27–33. http://dx.doi.org/10.1097/mao.0b013e31818f57ab.

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18

Bolner, Federico, Sara Magits, Bas van Dijk, and Jan Wouters. "Precompensating for spread of excitation in a cochlear implant coding strategy." Hearing Research 395 (September 2020): 107977. http://dx.doi.org/10.1016/j.heares.2020.107977.

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19

Zefirov, A. L., and I. A. Khalilov. "Appearance and spread of excitation in the frog motor nerve ending." Bulletin of Experimental Biology and Medicine 109, no. 3 (March 1990): 274–77. http://dx.doi.org/10.1007/bf00839634.

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20

Garza-Rios, Luis O., and Michael M. Bernitsas. "Analytical Expressions of the Stability and Bifurcation Boundaries for General Spread Mooring Systems." Journal of Ship Research 40, no. 04 (December 1, 1996): 337–50. http://dx.doi.org/10.5957/jsr.1996.40.4.337.

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Spread mooring systems (SMS) are labeled as general when they are not restricted by conditions of symmetry. The six necessary and sufficient conditions for stability of general SMS are derived analytically. The boundaries where static and dynamic loss of stability occur also are derived in terms of the system eigenvalues, thus providing analytical means for defining the morphogenesis that occurs when a bifurcation boundary is crossed. The equations derived in this paper provide analytical expressions of elementary singularities and routes to chaos for general mooring system configurations. Catastrophe sets are generated first by the derived expressions and then numerically using nonlinear dynamics and codimension-one and -two bifurcation theory; agreement is excellent. The mathematical model consists of the nonlinear, third-order maneuvering equations without memory of the horizontal plane, slow-motion dynamics—surge, sway, and yaw—of a vessel moored to several terminals. Mooring lines can be modeled by synthetic nylon ropes, chains, or steel cables. External excitation consists of time-independent current, wind, and mean wave drift forces. The analytical expressions derived in this paper apply to nylon ropes and current excitation. Expressions for other combinations of lines and excitation can be derived.

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21

Daniel, E. E., and F. Kostolanska. "Functional studies of nerve projections in the canine intestine." Canadian Journal of Physiology and Pharmacology 67, no. 9 (September 1, 1989): 1074–85. http://dx.doi.org/10.1139/y89-170.

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An in vivo model has been developed to study nerve connections in the canine intestine, using spread of field stimulated contractions recorded proximally and distally with strain gauges and local intra-arterial injections of drugs. Excitation spread orally for several centimetres, more effectively at lower frequencies of field stimulation. This excitation was blocked by local hexamethonium or by a combination of atropine and naloxone (each of which reduced the contractions). Distal excitation occurred after a longer delay than oral excitation; during the delay there was frequently an initial relaxation response. Distal excitation was greater at higher frequencies of field stimulation, but like oral excitation it was blocked by hexamethonium or by a combination of atropine and naloxone. Distal relaxation responses were unaffected by atropine or naloxone, but were abolished by hexamethonium. "Off" contractions, those that followed cessation of field stimulation, occurred at higher frequencies of field stimulation proximally and distally near the site of field stimulation and were blocked by atropine but not by naloxone or hexamethonium. The effects of all agents given locally extended beyond the sites of injection. These results suggest that a chain of cholinergic nerves with nicotinic synapses transmit excitation orally and distally to circular muscle; these effects seem to be facilitated proximally and distally by opioid nerves and to be inhibited initially distally by a noncholinergic mechanism. Explanations of these findings are proposed.Key words: opioid nerves, cholinergic nerves, vasoactive intestinal peptide as mediator, naloxone, atropine, hexamethonium, "off"-contractions, field stimulation.

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22

Blatter, Lothar A. "The intricacies of atrial calcium cycling during excitation-contraction coupling." Journal of General Physiology 149, no. 9 (August 10, 2017): 857–65. http://dx.doi.org/10.1085/jgp.201711809.

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23

Spitzer, Emily R., and Michelle L. Hughes. "Effect of Stimulus Polarity on Physiological Spread of Excitation in Cochlear Implants." Journal of the American Academy of Audiology 28, no. 09 (October 2017): 786–98. http://dx.doi.org/10.3766/jaaa.16144.

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AbstractContemporary cochlear implants (CIs) use cathodic-leading, symmetrical, biphasic current pulses, despite a growing body of evidence that suggests anodic-leading pulses may be more effective at stimulating the auditory system. However, since much of this research on humans has used pseudomonophasic pulses or biphasic pulses with unusually long interphase gaps, the effects of stimulus polarity are unclear for clinically relevant (i.e., symmetric biphasic) stimuli.The purpose of this study was to examine the effects of stimulus polarity on basic characteristics of physiological spread-of-excitation (SOE) measures obtained with the electrically evoked compound action potential (ECAP) in CI recipients using clinically relevant stimuli.Using a within-subjects (repeated measures) design, we examined the differences in mean amplitude, peak electrode location, area under the curve, and spatial separation between SOE curves obtained with anodic- and cathodic-leading symmetrical, biphasic pulses.Fifteen CI recipients (ages 13–77) participated in this study. All were users of Cochlear Ltd. devices.SOE functions were obtained using the standard forward-masking artifact reduction method. Probe electrodes were 5–18, and they were stimulated at an 8 (of 10) loudness rating (“loud”). Outcome measures (mean amplitude, peak electrode location, curve area, and spatial separation) for each polarity were compared within subjects.Anodic-leading current pulses produced ECAPs with larger average amplitudes, greater curve area, and less spatial separation between SOE patterns compared with that for cathodic-leading pulses. There was no effect of polarity on peak electrode location.These results indicate that for equal current levels, the anodic-leading polarity produces broader excitation patterns compared with cathodic-leading pulses, which reduces the spatial separation between functions. This result is likely due to preferential stimulation of the central axon. Further research is needed to determine whether SOE patterns obtained with anodic-leading pulses better predict pitch discrimination.

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24

Dodt, Hans-Ulrich, Giovanna DʼArcangelo, Elmar Pestel, and Walter Zieglgänsberger. "The spread of excitation in neocortical columns visualized with infrared-darkfield videomicroscopy." NeuroReport 7, no. 10 (July 1996): 1553–58. http://dx.doi.org/10.1097/00001756-199607080-00004.

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25

Becker, Klaus, Matthias Eder, Walter Zieglg??nsberger, and Hans-Ulrich Dodt. "WIN 55,212-2 decreases the spatial spread of neocortical excitation in vitro." NeuroReport 16, no. 9 (June 2005): 993–96. http://dx.doi.org/10.1097/00001756-200506210-00022.

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26

Fiedler, H. E., and P. Mensing. "The plane turbulent shear layer with periodic excitation." Journal of Fluid Mechanics 150 (January 1985): 281–309. http://dx.doi.org/10.1017/s0022112085000131.

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The influence of periodic excitation on a plane turbulent one-stream shear layer with turbulent separation was investigated. For the qualitative study flow visualization was employed. Quantitative data were obtained with hot-wire anemometry and spectrum analysis. It was found that sinusoidal perturbations with frequencies of order f0 [lsim ] u0/100θ0 (depending on excitation strength), introduced at the trailing edge are always amplified. Maximum amplification factors are observed for the lowest perturbation levels. The frequency and amplitude of excitation determine the downstream location of the amplification maximum in the flow. At sufficient amplitude two-dimensional vortices are formed which subsequently decay without pairing. The development of the periodic r.m.s. values along x follows a universal curve for all frequencies and amplitudes when properly normalized.At high excitation amplitudes the flow development depends strongly on the geometrical conditions of the excitation arrangement at the trailing edge. Thus regular vortex pairing as well as suppression of pairing can be achieved.The excited shear layer has considerably stronger, yet nonlinear, spread than the neutral. The region of vortex formation, irrespective of whether it includes pairing or not, is associated with a step-like increase in width, while after the position of maximum vortex energy, i.e. in the region of decay, the spread is reduced to values below the neutral. There the overall lateral fluctuation energy is increased, while the longitudinal may be decreased as compared with the neutral flow.

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27

Samartsev, Vitaly, Tatiana Mitrofanova, and Alexander Saiko. "Incoherent exciton echo on the CdSe/CdS/ZnS semiconductor quantum dots." EPJ Web of Conferences 220 (2019): 03023. http://dx.doi.org/10.1051/epjconf/201922003023.

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28

Mikami, Masato, Herman Saputro, Takehiko Seo, and Hiroshi Oyagi. "Flame Spread and Group-Combustion Excitation in Randomly Distributed Droplet Clouds with Low-Volatility Fuel near the Excitation Limit: a Percolation Approach Based on Flame-Spread Characteristics in Microgravity." Microgravity Science and Technology 30, no. 4 (March 3, 2018): 419–33. http://dx.doi.org/10.1007/s12217-018-9603-z.

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29

Farrington, R. B. "Infrared Imaging Results of an Excited Planar Jet." Journal of Solar Energy Engineering 115, no. 2 (May 1, 1993): 85–92. http://dx.doi.org/10.1115/1.2930036.

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Planar jets are used for many applications including heating, cooling, and ventilation. Generally, a planar jet provides good mixing within an enclosure. In building applications, the jet provides both thermal comfort and adequate indoor air quality. Increased mixing rates may reduce short circuiting of conditioned air, eliminate dead zones within the occupied zone, reduce energy costs, increase occupant comfort, and increase indoor air quality. This article discusses how an infrared imaging system was used to demonstrate how jet excitation affected the spread angle and the jet mixing efficiency. Infrared imaging captures a large number of data points in real time (over 50,000 data points per image) providing significant advantages over single-point measurements. We used a mesh screen with a time constant of approximately 0.3 seconds as a target for the infrared camera to detect temperature variations in the jet. The infrared images show that excitation of the jet caused increased jet spread. Digital data reduction and analysis show changes in jet isotherms and quantify the increased mixing caused by excitation.

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30

BIKTASHEVA, I. V., V. N. BIKTASHEV, W. N. DAWES, A. V. HOLDEN, R. C. SAUMAREZ, and A. M. SAVILL. "DISSIPATION OF THE EXCITATION FRONT AS A MECHANISM OF SELF-TERMINATING ARRHYTHMIAS." International Journal of Bifurcation and Chaos 13, no. 12 (December 2003): 3645–55. http://dx.doi.org/10.1142/s0218127403008909.

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The dissipation of the excitation wavefronts is a specific mechanism of propagation failure if the sharp gradient of the transmembrane voltage at the wavefront smears out and spread of voltage becomes diffusive, as the main excitation current becomes inactivated. This is produced by the normal kinetics of the ionic currents underlying the action potential. Here we demonstrate that the dissipation of the excitation wavefront can cause arrhythmia as well as lead to its self-termination. We use Courtemanche et al. model of human atrial action potential to demonstrate how reentry creates dynamic electrophysiologic inhomogeneity of the tissue. Local dissipation of the excitation front causes wave breaks and instantaneous displacement of the tip of the reentry, and the same mechanism can lead to elimination of all wavelets, as the inhomogeneity creates conditions for simultaneous dissipation of their excitation fronts.

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31

Vellinga, Dirk, Jeroen Johannes Briaire, David Michael Paul van Meenen, and Johannes Hubertus Maria Frijns. "Comparison of Multipole Stimulus Configurations With Respect to Loudness and Spread of Excitation." Ear and Hearing 38, no. 4 (2017): 487–96. http://dx.doi.org/10.1097/aud.0000000000000416.

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32

Athias, P., S. Jacquir, C. Tissier, D. Vandroux, S. Binczak, J. M. Bilbault, and M. Rossé. "Excitation spread in cardiac myocyte cultures using paired microelectrode and microelectrode array recordings." Journal of Molecular and Cellular Cardiology 42, no. 6 (June 2007): S3. http://dx.doi.org/10.1016/j.yjmcc.2007.03.007.

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33

Schoffnegger, Doris, Ruth Ruscheweyh, and Jürgen Sandkühler. "Spread of excitation across modality borders in spinal dorsal horn of neuropathic rats." Pain 135, no. 3 (April 2008): 300–310. http://dx.doi.org/10.1016/j.pain.2007.12.016.

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34

Walkowiak, Adam, Bozena Kostek, Artur Lorens, Anita Obrycka, Arkadiusz Wasowski, and Henryk Skarzynski. "Spread of Excitation (SoE) — A Non-Invasive Assessment of Cochlear Implant Electrode Placement." Cochlear Implants International 11, sup1 (June 2010): 479–81. http://dx.doi.org/10.1179/146701010x12671177204787.

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35

Richter, C.-P., S. M. Rajguru, A. I. Matic, E. L. Moreno, A. J. Fishman, A. M. Robinson, E. Suh, and J. T. Walsh. "Spread of cochlear excitation during stimulation with pulsed infrared radiation: inferior colliculus measurements." Journal of Neural Engineering 8, no. 5 (August 10, 2011): 056006. http://dx.doi.org/10.1088/1741-2560/8/5/056006.

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36

Kubota, Michinori, Shunji Sugimoto, Junsei Horikawa, Masahiro Nasu, and Ikuo Taniguchi. "Optical imaging of dynamic horizontal spread of excitation in rat auditory cortex slices." Neuroscience Letters 237, no. 2-3 (November 1997): 77–80. http://dx.doi.org/10.1016/s0304-3940(97)00806-9.

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37

Chesi, A. J. R., F. Rucker, Y. Tretter, G. ten Bruggencate, and C. Alzheimer. "Spread of Excitation in Chronically Lesioned Mouse Hippocampus Determined by Laser Scanning Microscopy." Experimental Neurology 152, no. 2 (August 1998): 177–87. http://dx.doi.org/10.1006/exnr.1998.6840.

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38

Hsu, C. M., and R. F. Huang. "Comparisons of Flow and Mixing Characteristics between Unforced and Excited Elevated Transverse Jets." Journal of Mechanics 30, no. 1 (November 14, 2013): 87–96. http://dx.doi.org/10.1017/jmech.2013.74.

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ABSTRACTThe influences of acoustic excitation on the velocity field and mixing characteristic of a jet in cross-flow were investigated in a wind tunnel. The acoustic excitation waves at resonance Strouhal number were generated by a loudspeaker. The time-averaged velocity field and streamlines of the excited elevated transverse jet in the symmetry plane were measured by a high-speed particle image velocimetry. The visual penetration height and spread width were obtained by using an image processing technique. The dispersion characteristics were obtained from the tracer-gas concentration measurement. The results showed that the streamline pattern of the non-excited transverse jet was significantly modified by the acoustic excitation—the bent streamlines evolved from the jet exit escalated and the vortex rings in the jet and tube wakes and the recirculation bubble in the jet wake disappeared. The time-averaged velocity distributions revealed that the excited transverse jet produces large momentum in the up-shooting direction so that the velocity trajectories were located at levels higher than those of the non-excited one. The mixing characteristics, which include the visual penetration height, spread width, and dispersion, were drastically improved by the acoustic excitation due to the changes in the flow structures. The excited transverse jet characterized at larger jet-to-crossflow momentum flux ratios presented larger improvement in the mixing characteristics than at lower jet-to-crossflow momentum flux ratios.

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39

Hofer, E., G. Urban, M. S. Spach, I. Schafferhofer, G. Mohr, and D. Platzer. "Measuring activation patterns of the heart at a microscopic size scale with thin-film sensors." American Journal of Physiology-Heart and Circulatory Physiology 266, no. 5 (May 1, 1994): H2136—H2145. http://dx.doi.org/10.1152/ajpheart.1994.266.5.h2136.

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To study the spread of excitation in ventricular heart preparations we have designed a fast, high-resolution recording and mapping system. Papillary muscles were dissected from the isolated guinea pig hearts. The preparation was fixed in a tissue bath and superfused with Tyrode solution. Linear and two-dimensional arrays of Ag/AgCl electrodes were made on glass with a thin-film technique. The transparent sensors with up to 24 electrodes (spaced 50, 90, or 180 microns apart) were positioned close to the surface of the preparation with a custom-designed three-dimensional micromanipulator. Extracellular signals were simultaneously recorded by a 24-channel data acquisition system with a 200 kHz per channel sample rate, with 12-bit amplitude resolution and a maximum data length of up to 3 MB. Digitized video images of the electrode array and the underlaying preparation were used to identify the locations of the recording sites. A UNIX-based computer system with a custom-designed data acquisition and database program was used to control the instruments and to manage the experimental data. This technique gave signals with excellent signal-to-noise ratios (up to 65 dB) and permitted accurate evaluation of the time and the site of the local activation with high resolution (to within 5 microseconds, 50 microns). We describe the spread of excitation within the area of a few cells and found a substantial dispersion of conduction velocities. Beat-to-beat comparison of activation patterns showed relatively small variations in the spread of excitation (a few microseconds).

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40

Svilainis, L., S. Kitov, A. Rodríguez, L. Vergara, V. Dumbrava, and A. Chaziachmetovas. "Comparison of spread spectrum and pulse signal excitation for split spectrum techniques composite imaging." IOP Conference Series: Materials Science and Engineering 42 (December 10, 2012): 012007. http://dx.doi.org/10.1088/1757-899x/42/1/012007.

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41

Snel-Bongers, Jorien, Jeroen J. Briaire, Filiep J. Vanpoucke, and Johan H. M. Frijns. "Spread of Excitation and Channel Interaction in Single- and Dual-Electrode Cochlear Implant Stimulation." Ear and Hearing 33, no. 3 (2012): 367–76. http://dx.doi.org/10.1097/aud.0b013e318234efd5.

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42

Goehring, Jenny L., Donna L. Neff, Jacquelyn L. Baudhuin, and Michelle L. Hughes. "Pitch ranking, electrode discrimination, and physiological spread-of-excitation using Cochlear's dual-electrode mode." Journal of the Acoustical Society of America 136, no. 2 (August 2014): 715–27. http://dx.doi.org/10.1121/1.4884881.

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43

Peres, A., and F. Andrietti. "Computer reconstruction of the spread of excitation in nerve terminals with inhomogeneous channel distribution." European Biophysics Journal 13, no. 4 (April 1986): 235–43. http://dx.doi.org/10.1007/bf00260370.

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44

Hung, Hsiao-Hui, Kuang-Yen Liu, and Kuo-Chun Chang. "Rocking behavior of bridge piers with spread footings under cyclic loading and earthquake excitation." Earthquakes and Structures 7, no. 6 (December 25, 2014): 1001–24. http://dx.doi.org/10.12989/eas.2014.7.6.1001.

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45

Rall, Jack A. "A perfect confluence of physiology and morphology: discovery of the transverse tubular system and inward spread of activation in skeletal muscle." Advances in Physiology Education 44, no. 3 (September 1, 2020): 402–13. http://dx.doi.org/10.1152/advan.00091.2020.

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By early 1954, there existed a plausible model of muscle contraction called the sliding filament model. In addition, the nature of muscle excitation was understood. Surprisingly, the link between the membrane excitation and contraction was entirely unknown. This dilemma has been called the time-distance paradox. The path to discovery of the missing link between excitation and contraction was a rocky one involving the simultaneous but independent development of physiological and morphological studies. From the viewpoint of physiology, significant events included the most thrilling moment of a scientific life, confirmation of a hypothesis that was wrong, a major surprise and shock, a result not expected from evolutionary relationships, and disappointment and confusion before clarity. From the viewpoint of morphology, there was the exciting beginning and rapid development of biological electron microscopy, heroic experiments, the importance of sample preparative procedures, and discovery of clues from the old light microscopic literature. However, it was the confluence of physiology and morphology that brought clarity and a major advance in understanding, leading to the discovery of the transverse tubular system and inward spread of activation in skeletal muscle.

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46

Jennings, Skyler G., and Tabitha Whitmore. "Simultaneous measurement of human auditory nerve and brainstem potentials: Effects of upward spread of excitation." Journal of the Acoustical Society of America 151, no. 4 (April 2022): A258. http://dx.doi.org/10.1121/10.0011252.

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Acoustic clicks evoke strong synchrony of auditory-nerve (AN) fibers, thereby eliciting a compound action potential (CAP); however, synchrony is reduced by the delay of the cochlear traveling wave. Upward-frequency chirps compensate for this delay, resulting in larger CAPs evoked by chirps than clicks. Our model simulations of CAPs suggest that chirps presented at high intensities (100 dB peSPL) adapt basal AN fibers via upward spread of excitation of low-frequency chirp components. This adaptation results in less-than-or-equal-to CAP amplitudes and distorted CAP morphology compared to CAPs evoked by clicks. Simulations show that these effects on CAP amplitude and morphology can be avoided by reducing the amplitude of the low-frequency components of the chirp (i.e., modified chirp). Here we present CAPs from 12 young adults with NH, which for high stimulus intensities, exhibit reduced amplitudes and broader CAP morphology for chirps than clicks, whereas CAP amplitudes for modified chirps exceed those for clicks, consistent with model simulations. The distorted CAP morphology in response to high-level chirps is consistent with adaptation of AN responses and broad cochlear excitation. Interestingly, the deleterious effects of high-level chirps on CAP amplitude and morphology are reduced or absent in simultaneous recordings of the auditory brainstem response.

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Hill, Jacqueline, Seong-Ki Lee, Prattana Samasilp, and Corey Smith. "Pituitary adenylate cyclase-activating peptide enhances electrical coupling in the mouse adrenal medulla." American Journal of Physiology-Cell Physiology 303, no. 3 (August 1, 2012): C257—C266. http://dx.doi.org/10.1152/ajpcell.00119.2012.

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Neuroendocrine adrenal medullary chromaffin cells receive synaptic excitation through the sympathetic splanchnic nerve to elicit catecholamine release into the circulation. Under basal sympathetic tone, splanchnic-released acetylcholine evokes chromaffin cells to fire action potentials, leading to synchronous phasic catecholamine release. Under elevated splanchnic firing, experienced under the sympathoadrenal stress response, chromaffin cells undergo desensitization to cholinergic excitation. Yet, stress evokes a persistent and elevated adrenal catecholamine release. This sustained stress-evoked release has been shown to depend on splanchnic release of a peptide transmitter, pituitary adenylate cyclase-activating peptide (PACAP). PACAP stimulates catecholamine release through a PKC-dependent pathway that is mechanistically independent of cholinergic excitation. Moreover, it has also been reported that shorter term phospho-regulation of existing gap junction channels acts to increase junctional conductance. In this study, we test if PACAP-mediated excitation upregulates cell-cell electrical coupling to enhance chromaffin cell excitability. We utilize electrophysiological recordings conducted in adrenal tissue slices to measure the effects of PACAP stimulation on cell coupling. We report that PACAP excitation increases electrical coupling and the spread of electrical excitation between adrenal chromaffin cells. Thus PACAP acts not only as a secretagogue but also evokes an electrical remodeling of the medulla, presumably to adapt to the organism's needs during acute sympathetic stress.

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Zipfel, Warren R., Rebecca M. Williams, and W. Watt. "Application of Multiphoton Imaging to Study of the Vasculature." Microscopy and Microanalysis 3, S2 (August 1997): 335–36. http://dx.doi.org/10.1017/s1431927600008564.

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Nonlinear or multiphoton fluorescence microscopy utilizes the simultaneous absorption of two (or three) longer wavelength photons to excite fluorophores (Denk et.al., 1990). For example, UV absorbing fluorophores such as DAPI or lndo-1 are excited using 700 nm near infrared light rather than 350 nm UV excitation. This relatively new form of laser scanning fluorescence microscopy has excellent optical sectioning capabilities in thick, highly scattering tissues. The high degree of intrinsic optical sectioning arises from the spatial nature of the excitation dependence, rather than from a confocal aperture or deconvolution algorithm. The fluorescence arising from any point in the specimen depends on the second or third power of the intensity (i.e. two and three photon excitation, respectively). This squaring (or cubing) of the illumination point spread function effectively confines the excitation to a tenth of a femtoliter optical volume when using a high NA lens. 680 to 1100 nm mode-locked lasers producing pulses of 100 femtosecond duration at a repetition rate of 80 Mhz are used to efficiently produce fluorescence excitation at average powers that are usually in the 0.5 to 10 mW range at the sample.

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van der Beek, Feddo B., Jeroen J. Briaire, and Johan H. M. Frijns. "Effects of parameter manipulations on spread of excitation measured with electrically-evoked compound action potentials." International Journal of Audiology 51, no. 6 (February 8, 2012): 465–74. http://dx.doi.org/10.3109/14992027.2011.653446.

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Goehring, Jenny L., Donna L. Neff, Jacquelyn L. Baudhuin, and Michelle L. Hughes. "Pitch ranking, electrode discrimination, and physiological spread of excitation using current steering in cochlear implants." Journal of the Acoustical Society of America 136, no. 6 (December 2014): 3159–71. http://dx.doi.org/10.1121/1.4900634.

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