Theoretical and Practical Aspects of the Nonlinear Dynamics' Methods of Heart Rate Variability Analyses in Tachyarrhythmia Patients Underwent Radiofrequency Catheter Ablation.

Purpose: This study explores the use of heart rate variability (HRV) analysis, a noninvasive technique for assessing the autonomic nervous system, by applying nonlinear dynamics and chaos theory to detect chaotic behavior in RR intervals and assess cardiovascular health.

Methods: Employing the "System Analysis of Heart Rate Dynamics" (SADR) program, this research combines chaos analysis with the short-time Fourier transform to assess nonlinear dynamic parameters in HRV. It includes constructing phase portraits in Takens space and calculating measures of chaos to identify deterministic chaos indicators.

Simultaneous electromechanical monitoring in engineered heart tissues using a mesoscale framework.

Engineered heart tissues (EHTs) generated from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) represent powerful platforms for human cardiac research, especially in drug testing and disease modeling. Here, we report a flexible, three-dimensional electronic framework that enables real-time, spatiotemporal analysis of electrophysiologic and mechanical signals in EHTs under physiological loading conditions for dynamic, noninvasive, longer-term assessments. These electromechanically monitored EHTs support multisite measurements throughout the tissue under baseline conditions and in response to stimuli.

Coordinated transcriptional control of the adult ventricular conduction system.

The cardiac conduction system (CCS) orchestrates the electrical impulses that enable coordinated contraction of the cardiac chambers. The T-box transcription factors and are required for cardiac conduction system development and associated with overlapping and distinct human cardiac conduction system diseases. We evaluated the coordinated role of and in the murine ventricular conduction system (VCS).

Politicizing science funding undermines public trust in science, academic freedom, and the unbiased generation of knowledge.

This commentary documents how federal funding agencies are changing the criteria by which they distribute taxpayer money intended for scientific research. Increasingly, STEMM (Science, Technology, Engineering, Mathematics, and Medicine) funding agencies are requiring applicants for funding to include a plan to advance DEI ("Diversity, Equity, and Inclusion") in their proposals and to dedicate a part of the research budget to its implementation. These mandates undermine the academic freedom of researchers and the unbiased generation of knowledge needed for a well-functioning democracy.