Previous studies have examined the influence of the gap-junction discontinuity on the steady-state response of a cardiac cable to electrical defibrillation. It is important to understand when steady-state conditions may be assumed. For this reason, the transient, subthreshold behavior of a discontinuous cardiac cable is examined in this study. The behavior of the cable reflects two characteristics: 1) the continuous nature of the entire cable and 2) the isolated behavior of individual cells imposed by the junction discontinuity. The results show two effective time constants of activation: a large time constant corresponding to the time constant of a continuous cable of equivalent length, and a small time constant reflecting the rapid activation of an isolated cell. The rapid activation establishes a voltage gradient across each cell of the cable with one end of the cell hyperpolarized and the opposite end depolarized. This pattern of hyperpolarization and depolarization reaches a maximum value in approximately 3 microseconds and may play an important role in the mechanism of defibrillation.
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http://dx.doi.org/10.1109/10.125011 | DOI Listing |
Pulmonology
December 2025
Sorbonne Université, INSERM, UMRS1158 Neurophysiologie Respiratoire Expérimentale et Clinique, Paris, France.
Background: Nasal high flow (NHF) has been proposed to sustain high intensity exercise in people with COPD, but we have a poor understanding of its physiological effects in this clinical setting.
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Study Design And Methods: Randomized single-blind crossover trial including COPD patients.
J Mol Model
January 2025
College of Chemical Engineering, Fuzhou University, Fuzhou, 350116, People's Republic of China.
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View Article and Find Full Text PDFHeliyon
January 2025
Department of Mathematics and Statistics, The University of Lahore, Sargodha 40100, Pakistan.
This paper addresses the challenges of maintaining stability in heterogeneous vehicle platooning under the influence of communication disruptions caused by Byzantine attacks within a leader-follower framework. To enhance resilience, we propose a nonlinear control strategy tailored for a third-order heterogeneous dynamic model, integrating leader-follower interconnections with adaptable control gains. Utilizing a constant time headway spacing policy with gap adjustments, we derive control gains that secure internal platoon stability.
View Article and Find Full Text PDFACS Appl Nano Mater
March 2024
Department of Radiology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States.
Photon-counting mammography is an emerging modality that allows for spectral imaging and provides a differentiation of material compositions. The development of photon-counting mammography-specific contrast agents has yet to be explored. In this study, the contrast, sensitivity, and organ dose between silver sulfide nanoparticles (AgS-NPs) and a clinically approved iodinated agent (iopamidol) were investigated using a contrast-embedded gradient ramp phantom and a prototype scanner.
View Article and Find Full Text PDFFront Microbiol
January 2025
Laboratory of Molecular Biotechnology, National Center for Biotechnology, Astana, Kazakhstan.
fungal species are considered major plant pathogens, infecting various crops and resulting in significant agricultural losses. Additionally, these species can contaminate grain with multiple mycotoxins that are harmful to humans and animals. Efficient pest management relies on timely detection and identification of phytopathogens in plant and grain samples, facilitating prompt selection of a crop protection strategy.
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