Cardiac restitution has been described both in terms of ionic models-systems of ODE's-and in terms of mapping models. While the former provide a more fundamental description, the latter are more flexible in trying to fit experimental data. Recently we proposed a two-dimensional mapping that accurately reproduces restitution behavior of a paced cardiac patch, including rate dependence and accommodation. By contrast, with previous models only a qualitative, not a quantitative, fit had been possible. In this paper, a theoretical foundation for the new mapping is established by deriving it as an asymptotic limit of an idealized ionic model.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2605722 | PMC |
| http://dx.doi.org/10.1007/s11071-007-9202-9 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Covalently crosslinked carboxymethyl chitosan beads containing SiO and ionic polymer for efficient adsorptive removal of methylene blue.
Int J Biol Macromol
January 2025
College of Materials Science and Engineering, Nanjing Tech University, Nanjing 211816, PR China. Electronic address:
The carboxymethyl chitosan (CMCS)-based porous beads are still criticized for their limited number of binding sites, which impairs their efficacy in removing aqueous pollutants. To overcome this challenge, this work introduces the production of covalently crosslinked CMCS-based beads containing SiO and poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPS). The porous composite beads not only possess remarkable stability under acidic conditions, but also have abundant active binding sites for adsorption.
View Article and Find Full Text PDFAqueous Solubility of Sodium and Chloride Salts of Glycine─"Uncommon" Common-Ion Effects of Self-Titrating Solids.
Mol Pharm
January 2025
Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, 8000 Utopia Parkway, Queens, New York 11439, United States.
Although glycine is the simplest of the amino acids, its solution and solid-state properties are far from straightforward. The aqueous solubility of glycine plays an important role in various applications, including nutrition, food products, biodegradable plastics, and drug development. There is evidence that glycine in subsaturated pH 3-8 solutions forms a dimer, as suggested by several techniques.
View Article and Find Full Text PDFEntropy generation and water conservation in the mammalian nephron.
J Comp Physiol B
January 2025
Departamento de Fisiologia, Instituto de Biociências da Universidade de São Paulo, São Paulo, Brazil.
During the transition from fresh waters to terrestrial habitats, significant adaptive changes occurred in kidney function of vertebrates to cope with varying osmotic challenges. We investigated the mechanisms driving water conservation in the mammalian nephron, focusing on the relative contributions of active ion transport and Starling forces. We constructed a thermodynamic model to estimate the entropy generation associated with different processes within the nephron, and analyzed their relative importance in urine formation.
View Article and Find Full Text PDFNegative memory capacitance and ionic filtering effects in asymmetric nanopores.
Nat Nanotechnol
January 2025
Department of Bioengineering, University of California, Riverside, Riverside, CA, USA.
The pervasive model for a solvated, ion-filled nanopore is often a resistor in parallel with a capacitor. For conical nanopore geometries, here we propose the inclusion of a Warburg-like element, which is necessary to explain otherwise anomalous observations such as negative capacitance and low-pass filtering of translocation events (we term this phenomenon as Warburg filtering). The negative capacitance observed here has long equilibration times and memory (that is, mem-capacitance) at negative voltages.
View Article and Find Full Text PDFNon vertical ionization-dissociation model for strong IR induced dissociation dynamics of [Formula: see text].
Sci Rep
January 2025
School of Physics and Information Technology, Shaanxi Normal University, Xi'an, 710062, Shaanxi, People's Republic of China.
Electron-nuclear coupling plays a crucial role in strong laser induced molecular dissociation dynamics. The interplay between electronic and nuclear degrees of freedom determines the pathways and outcomes of molecular fragmentation. However, a full quantum mechanical treatment of electron-nuclear dynamics is computationally intensive.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!