Binding of Oppositely Charged Membranes and Membrane Reorganization

We consider the electrostatic interaction between two rigid membranes, with different surface charge densities of opposite sign, across an aqueous solution without added salt. Exact solutions to the nonlinear Poisson-Boltzmann equation are obtained and their physical meaning discussed. We also calculate the electrostatic contribution to the free energy and discuss the renormalization of the area per head group of the charged lipids arising from the Coulomb interaction.Comment: 13 pages, 6 figures, to be published in EJP

Biopsychosocial Resilience through a Complex Adaptive Systems Lens: A Narrative Review of Nonlinear Modeling Approaches

Human resilience is often considered as static traits using a reductionist approach. More recent work has demonstrated it to be a dynamic and emergent property of complex systems. This narrative review explores human resilience through a self-organizing framework with a specific emphasis on the application of nonlinear modeling approaches. Four classes of approaches are examined: univariate dynamics, bivariate coupling, topological modeling, and network modeling. Univariate dynamics capture the temporal structure and flexibility within a single time series, while bivariate coupling approaches quantify the interaction dynamics and coordination between two time series. Topological modeling identifies bifurcations and attractor dynamics as signals of critical transitions relative to emergence and system stability. Network modeling represents system structure with a focus on connectivity, flexibility, and system integrity. Applying a complex systems framework, this review provides insights into data modeling opportunities for characterizing important features of a system”s capacity to bounce back and recover from stress. These characteristics are connected to meta-flexibility, which characterizes a system”s adaptive responsiveness to stressors, including post-traumatic growth, and the relation between meta-flexibility and metastability is discussed. Overall, this review provides a foundation of tools for researchers interested in under-standing human resilience through a complex systems framework