Computational Simulation of Colorectal Cancer Biomarker Particle Mobility in a 3D Model

Even though some methods for the detection of colorectal cancer have been used clinically, most of the techniques used do not consider the in situ detection of colorectal cancer (CRC) biomarkers, which would favor in vivo real-time monitoring of the carcinogenesis process and consequent studies of the disease. In order to give a scientific and computational framework ideal for the evaluation of diagnosis techniques based on the early detection of biomarker molecules modeled as spherical particles from the computational point of view, a computational representation of the rectum, stool and biomarker particles was developed. As consequence of the transport of stool, there was a displacement of CRC biomarker particles that entered the system as a result of the cellular apoptosis processes in polyps with a length lower than 1 cm, reaching a maximum velocity of 3.47×10-3 m/s. The biomarkers studied showed trajectories distant to regions of the polyp of origin in 1 min of simulation. The research results show that the biomarker particles for CRC respond to the variations in the movements of the stool with trajectories and speeds that depend on the location of the injury, which will allow locating the regions with the highest possibilities of catching particles through in situ measurement instruments in the future.

Local hemodynamic analysis of the C-Pulse Device by 3D fluid-structure interaction simulation

Background: C-Pulse is a new, nonblood contacting device based on the concept of counter-pulsation that is designed for long-term implantation. However, there is a lack of comprehensive investigation of the pressure and velocity fields under the action of C-Pulse. Aim: In this paper, we aim to conduct a numerical simulation of the underlying mechanism of the device in order to analyze its performance and related undesirable issues. Materials & methods: A 3D finite element model is utilized to simulate the mechanism of the blood pumping. Results & conclusion: The simulation well reproduced the essential characteristics of the C-Pulse. Preliminary results were in a reasonable range while a couple of irregular flow patterns were identified.

Fluid–Structure Interaction Modeling Applied to Peristaltic Pump Flow Simulations

In this study, fluid–structure interaction (FSI) modeling was applied for predicting the fluid flow in a specific peristaltic pump, composed of one metallic roller and a hyperelastic tube pumping a viscous Newtonian fluid. Hyperelastic material dynamics and turbulence flow dynamics were coupled in order to describe all the physics of the pump. The commercial finite element software ABAQUS 6.14 was used to investigate the performance of the pump with a 3D transient model. By using this model, it was possible to predict the von Mises stresses in the tube and flow fluctuations. The peristaltic pump generated high pressure and flow pulses due to the interaction between the roller and the tube. The squeezing and relaxing of the tube during the operative phase allowed the liquid to have a pulsatile behavior. Numerical simulation data results were compared with one cycle pressure measurement obtained from pump test loop data, and the maximum difference between real and simulated data was less than 5%. The applicability of FSI modeling for geometric optimization of pump housing was also discussed in order to prevent roller and hose parts pressure peaks. The model allowed to investigate the effect of pump design variations such as tube occlusion, tube diameter, and roller speed on the flow rate, flow fluctuations, and stress state in the tube.

Effect of melting heat transfer on peristalsis in the presence of thermal radiation and Joule heating

Mathematical model is developed for peristaltic flow of viscous fluid through a compliant wall channel subject to melting heat transfer. Fluid is incompressible and magnetohydrodynamic. Analysis has been performed in the presence of Joule heating and thermal radiation. Solutions for small wave number are obtained. Physical quantities of interest are examined for various parameters of interest.

Convective heat and mass transfer analysis on peristaltic flow of Williamson fluid with Hall effects and Joule heating

This paper is retracted from IJB due to misconduct.