Douglas Kelley
Professor of Mechanical Engineering
Areas of Expertise
Biography
Education
Virginia Tech
BS
Electrical Engineering
2000
Auburn University
MS
Physics
2004
University of Maryland
PhD
Physics
2009
Selected Articles
Sensitivity analysis on a network model of glymphatic flow
Journal of the Royal Society InterfaceDouglas H. Kelley, Kimberly A. S. Boster, Jeffrey Tithof, Douglas D. Cook, and John H. Thomas
2022-06-01
Intracranial cerebrospinal and interstitial fluid (ISF) flow and solute transport have important clinical implications, but limited in vivo access to the brain interior leaves gaping holes in human understanding of the nature of these neurophysiological phenomena. Models can address some gaps, but only insofar as model inputs are accurate. We perform a sensitivity analysis using a Monte Carlo approach on a lumped-parameter network model of cerebrospinal and ISF in perivascular and extracellular spaces in the murine brain.
Oscillations of the large-scale circulation in experimental liquid metal convection at aspect ratios 1.4–3
Journal of Fluid MechanicsDouglass H. Kelley, Jonathan S. Cheng, Ibrahim Mohammad, Bitong Wang, Declan F. Keogh, and Jarod M. Forer
2022-10-06
We investigate the scaling properties of the primary flow modes and their sensitivity to aspect ratio in a liquid gallium (Prandtl number Pr=0.02) convection system through combined laboratory experiments and numerical simulations. We survey cylindrical aspect ratios 1.4≤Γ≤3 and Rayleigh numbers 104≲Ra≲106. In this range the flow is dominated by a large-scale circulation (LSC) subject to low-frequency oscillations. In line with previous studies, we show robust scaling of the Reynolds number Re with Ra and we confirm that the LSC flow is dominated by a jump-rope vortex (JRV) mode whose signature frequency is present in velocity and temperature measurements.
Artificial intelligence velocimetry reveals in vivo flow rates, pressure gradients, and shear stresses in murine perivascular flows
Proceedings of the National Academy of SciencesDouglass H. Kelley, Kimberly A.S. Boster, Shengze Cai, and Antonio Ladrón-de-Guevara,
2023-03-29
Diseases such as Alzheimer’s and small vessel disease are linked to alterations of flow in the perivascular spaces that surround cerebral blood vessels and transport water-like fluids around brain tissue. Understanding the function, failure, and potential rehabilitation of the system depends on high-fidelity, in vivo quantification of flow rates, pressure, and shear stress, which have previously been unavailable. We show that artificial intelligence velocimetry (AIV), which integrates sparse two-dimensional (2D) in vivo velocity measurements with physics-informed neural networks, can accurately infer high-resolution pressure and shear stresses.
Glymphatic influx and clearance are accelerated by neurovascular coupling
Nature NeuroscienceDouglas H. Kelley, Stephanie Holstein-Rønsbo, Yiming Gan, Michael J. Giannetto, Martin Kaag Rasmussen, Björn Sigurdsson, Felix Ralf Michael Beinlich, Laura Rose, Verena Untiet, Lauren M. Hablitz, and Maiken Nedergaard
2023-06-01
Functional hyperemia, also known as neurovascular coupling, is a phenomenon that occurs when neural activity increases local cerebral blood flow. Because all biological activity produces metabolic waste, we here sought to investigate the relationship between functional hyperemia and waste clearance via the glymphatic system.
Perivascular pumping of cerebrospinal fluid in the brain with a valve mechanism
Journal of the Royal Society InterfaceDouglas H. Kelley, Yiming Gan, Stephanie Holstein-Rønsbo, Maiken Nedergaard, Kimberly A. S. Boster, and John H. Thomas
2023-09-20
The flow of cerebrospinal fluid (CSF) along perivascular spaces (PVSs) is an important part of the brain’s system for clearing metabolic waste. Experiments reveal that arterial motions from cardiac pulsations and functional hyperaemiadrive CSF in the same direction as the blood flow, but the mechanism producing this directionality is unclear. We present two models, one based on the full equations of fluid dynamics and the other using lumped parameters, in which the astrocyte endfeet function as valves, regulating flow between the PVS and the ECS.