A recent functional model of the left ventricle characterizes the ventricle's contractile state with parameters, rather than variables. The ventricle is treated as a pressure generator that is time and volume dependent. The heart's complex dynamics develop from a single equation based on the formation and relaxation of crossbridge bonds within underlying heart muscle. This equation permits the calculation of ventricular elastance via E(v) = ∂p(v)/∂V(v). This heart model is defined independently from load properties, and ventricular elastance is dynamic and reflects changing numbers of crossbridge bonds. The model parameters were extracted from measured pressure and volume data from isolated canine hearts. The purpose of this paper is to present in some detail how to describe a particular canine left ventricle from measured data. The model is also extended to include heart rate variability, which arises naturally from the model structure. Computed results compare favorably with measurements both in this study and from the literature.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1109/IEMBS.2011.6091681 | DOI Listing |
J Dent Sci
January 2025
Department of Dentistry, College of Dentistry, National Yang Ming Chiao Tung University, Taipei, Taiwan.
Background/purpose: Temporomandibular joint (TMJ) arthritis causes inflammation and degradation of the mandibular condylar cartilage and subchondral bone. Complete Freund's adjuvant (CFA) and collagen-induced arthritis (CIA) are models for studying TMJ arthritis. While micro-computed tomography (micro-CT) is crucial for three-dimensional (3D) bone analysis, it has limitations in imaging nonmineralized tissues.
View Article and Find Full Text PDFIn Vitro Model
February 2022
School of Biomedical Engineering, Colorado State University, Fort Collins, CO USA.
Purpose: Present blood-contacting materials have not yet demonstrated to be effective in reducing blood coagulation without causing additional side effects clinically. We have developed an endothelial glycocalyx-inspired biomimetic surface that combines nanotopography, heparin presentation, and nitric oxide (NO)-releasing features. The resulting modified surfaces have already shown promise in reducing unfavorable blood-material interactions using platelet-rich plasma.
View Article and Find Full Text PDFJ Appl Crystallogr
January 2024
NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland, USA.
Neutron reflectometry (NR) is a powerful technique for interrogating the structure of thin films at interfaces. Because NR measurements are slow and instrument availability is limited, measurement efficiency is paramount. One approach to improving measurement efficiency is active learning (AL), in which the next measurement configurations are selected on the basis of information gained from the partial data collected so far.
View Article and Find Full Text PDFEcol Evol
January 2025
Universidad Regional Amazónica Ikiam Tena Ecuador.
Neotropical regions near the equator are recognized as speciation "hot spots" reflecting their abundant biodiversity. In western South America, the coasts of Panama, Colombia, Ecuador, the Galápagos Archipelago, and northern Peru form the Tropical Eastern Pacific biome. This area has the greatest heterogeneity of sympatric fiddler crab species of any portion of the planet.
View Article and Find Full Text PDFFront Cardiovasc Med
January 2025
Department of Medical Imaging, The Second Hospital of Hebei Medical University, Shijiazhuang, China.
Objectives: To evaluate the feasibility of utilizing cardiac computer tomography (CT) images for extracting the radiomic features of the myocardium at the junction between the left atrial appendage (LAA) and the left atrium (LA) in patients with atrial fibrillation (AF) and to evaluate its asscociation with the risk of AF.
Methods: A retrospective analysis was conducted on 82 cases of AF and 56 cases in the control group who underwent cardiac CT at our hospital from May 2022 to May 2023, with recorded clinical information. The morphological parameters of the LAA were measured.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!