We formulate in general terms the equations for axisymmetric and fully 3D models of a hydrocephalic brain. The model is developed using small strain poroelasticity that includes non-linear permeability. The axisymmetric model is solved for four ventricle shapes, an ellipsoid, a 'peanut' shape, a 'cross' shape and a 'bone' shape. The distribution of fluid pressure, velocity and content in the deformed parenchyma for a blocked aqueduct provides new qualitative insight into hydrocepahlus. Some observations are offered for two forms of cerebrospinal fluid flow abnormality, normal pressure hydrocephalus and idiopathic intracranial hypertension. The model is extended to include a gravitational term in the governing equations and the effect of hydrostatic pressure variation is considered. Results of a fully 3D simulations are described for two horn-like lateral ventricles and one case with two lateral ventricles and a third ventricle.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1093/imammb/dql014 | DOI Listing |
Micromachines (Basel)
October 2024
ALiCE-Laboratório Associado em Engenharia Química, Faculdade de Engenharia da Universidade do Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
Due to their nature, using shear thickening fluids (STFs) in engineering applications has sparked an interest in developing energy-dissipating systems, such as damping devices or shock absorbers. The Rheinforce technology allows the design of customized energy dissipative composites by embedding microfluidic channels filled with STFs in a scaffold material. One of the reasons for using microfluidic channels is that their shape can be numerically optimized to control pressure drop (also known as rectifiers); thus, by controlling the pressure drop, it is possible to control the energy dissipated by the viscous effect.
View Article and Find Full Text PDFTransp Porous Media
February 2024
Aerospace and Mechanical Engineering, USC Viterbi School of Engineering, Los Angeles, CA 90089, USA.
The purpose of this study is to systematically examine the basic fluid dynamics associated with a fully liquid region within a porous material. This work has come about as a result of our investigation on the ocular fluid dynamics and transport process in a partially liquefied vitreous humor. The liquid is modeled as a sphere with Stokes flow while the surrounding infinite porous region is described by Brinkman flow.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
October 2024
Department of Civil Engineering, Arak University, Arak, Iran.
J Acoust Soc Am
August 2024
Department of Meteorology, The Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Colloids Surf B Biointerfaces
October 2023
Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
The study discusses pitfalls in attempts to determine reliable surface tension values for the culture media and their extracts for two biosurfactant-producing yeast strains: Rhodotorula graminis and Rhodotorula babjevae. The values obtained from an Axisymmetric Drop Shape Analysis (ADSA) tensiometer showed systematically more and more shallow dynamic surface tension decays, suggesting a deterioration of their surface activity. The rate of this apparent surface activity loss was shown to depend on the sample history, with slower changes observed in vigorously shaken samples.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!