75th Annual Meeting of the American Physical Society’s Division of Fluid Dynamics (APS DFD)
The 75th Annual Meeting began on Sunday, November 20, 2022, and ended on Tuesday, November 22, 2022. ...
16 December, 2022
/ 0 Comments
Catch up on the latest work and news from the Vlachos Research Group.
Multi-feature-based Robust Cell Tracking
We present a fully automated, adaptive, and robust feature-based cell tracking algorithm for the accurate detection and tracking of cells using time-lapse images. Our algorithm tackles measurement limitations twofold. First, we use Hessian filtering and adaptive thresholding to detect the cells in images, overcoming spatial...
02 October, 2022
/ 0 Comments
Spatiotemporal measurement of concentration-dependent diffusion coefficient
With advancements in biotechnology, the production of highly concentrated antibody formulations for subcutaneous injections is becoming common in the biopharmaceutical industry. Measurement of transport and more importantly diffusion of proteins in tissues is essential in drug development. There is evidence suggesting that the assumption of the...
30 May, 2022
/ 0 Comments
Uncertainty estimation for ensemble particle image velocimetry
Particle Image Velocimetry (PIV) is a widely used non-invasive approach to finding a fluid flow velocity using tracer particles. Performing PIV measurement where the Signal-to-Noise Ratio (SNR) in the correlation plane is low can be unreliable and challenging. To address this issue, ensemble PIV has...
28 May, 2022
/ 0 Comments
A multi-modality approach for enhancing 4D flow MRI via sparse representation
4D flow magnetic resonance imaging (MRI) allows for the in vivo acquisition of time-resolved three-dimensional (3D) blood flow, enabling the evaluation of hemodynamic quantities for cerebral aneurysms (CAs). However, the accuracy of flow-derived hemodynamic quantities such as pressure and wall shear stress (WSS) is affected...
27 January, 2022
/ 0 Comments
Input waveform shape effects onset and development of transition to turbulence in pulsatile pipe flow
Transition to turbulence in pulsatile pipe flow is of interest in a variety of biological flow domains including in the left ventricle and aorta, aneurysms, and stenotic vessels. Transitional flow can critically alter distributions of important hemodynamic parameters such as wall shear stress (WSS). Many previous...
22 September, 2021
/ 0 Comments
Novel autonomous “entropy line-fit” (ELF) thresholding criterion for proper orthogonal decomposition (POD)
Proper orthogonal decomposition (POD) is often used to remove experimental or measurement noise from velocity fields by producing a reduced order model (ROM) of the dataset. The accuracy of POD is primarily governed by the choice of which POD “modes” to use when reconstructing the...
22 September, 2021
/ 0 Comments
Novel density- and viscosity-matched blood analog for use with PDMS Sylgard
Silicone Sylgard 184 (PDMS) is commonly used when manufacturing geometries for bioflow studies due to its optical transparency and compliant nature. However, for use with particle image velocimetry (PIV), a suitable blood analog working fluid is needed which both matches the physical properties of blood...
22 September, 2021
/ 0 Comments
Divergence-free constrained phase unwrapping and denoising for 4D flow MRI
4D flow magnetic resonance imaging (MRI) allows for in vivo acquisition of time-resolved three-dimensional (3D) blood flow, thus enabling quantitative analysis of volumetric, time-varying hemodynamic quantities such as flow rates, wall shear stress (WSS), pressure difference, etc. 4D flow MRI is based on the phase...
14 September, 2021
/ 0 Comments
Soap Film Patterns Versus Flow Structures: Do they match?
The value of the flowing soap film as an experimental platform depends on its ability to approximate the two-dimensional Navier-Stokes equation. A variety of experimental techniques have been applied to characterize the soap film patterns, with the measured quantities being the thickness and the velocity...
09 September, 2021
/ 0 Comments