Model Comparison and Assessment for Single Particle Tracking in Biological Fluids

• 成果类型: Article
• 署名作者: Lysy, Martin; Pillai, Natesh S.; Hill, David B.; Forest, M. Gregory; Mellnik, John W. R.; Vasquez, Paula A.; McKinley, Scott A.
• 署名单位: University of Waterloo; Harvard University; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina School of Medicine; University of North Carolina; University of North Carolina Chapel Hill; University of North Carolina School of Medicine; University of South Carolina System; University of South Carolina Columbia; Tulane University
• 刊物名称: JOURNAL OF THE AMERICAN STATISTICAL ASSOCIATION
• ISSN/ISSBN: 0162-1459
• DOI: 10.1080/01621459.2016.1158716
• 发表日期: 2016
• 页码: 1413-1426
• 关键词: human cervical-mucus; anomalous diffusion; Bayes Factors; soft matter; intracellular-transport; rapid-transport; P-values; glycoproteins; microheterogeneity; microrheology

摘要

State-of-the-art techniques in passive particle-tracking microscopy provide high-resolution path trajectories of diverse foreign particles in biological fluids. For particles on the order of 1 mu m diameter, these paths are generally inconsistent with simple Brownian motion. Yet, despite an abundance of data confirming these findings and their wide-ranging scientific implications, stochastic modeling of the complex particle motion has received comparatively little attention. Even among posited models, there is virtually no literature on likelihood-based inference, model comparisons, and other quantitative assessments. In this article, we develop a rigorous and computationally efficient Bayesian methodology to address this gap. We analyze two of the most prevalent candidate models for 30-sec paths of 1 mu m diameter tracer particles in human lung mucus: fractional Brownian motion (fBM) and a Generalized Langevin Equation (GLE) consistent with viscoelastic theory. Our model comparisons distinctly favor GLE over fBM, with the former describing the data remarkably well up to the timescales for which we havereliable information. Supplementary materials for this article are available online.