Progression of blood-borne viruses through bloodstream: A comparative mathematical study.

BACKGROUND AND OBJECTIVES: Blood-borne pathogens are contagious microorganisms that can cause life-threatening illnesses, and are found in human blood. It is crucial to examine how these viruses spread through blood flow in the blood vessel. Keeping that in view, this study aims to determine how blood viscosity, and diameter of the viruses can affect the virus transmission through the blood flow in the blood vessel. A comparative study of bloodborne viruses (BBVs) such as HIV, Hepatitis B, and C, has been addressed in the present model. A couple stress fluid model is used to represent blood as a carrying medium for virus transmission. The Basset-Boussinesq-Oseen equation is taken into account for the simulation of virus transmission. METHODS: An analytical approach to derive the exact solutions under the assumption of long wavelength and low Reynolds number approximations is employed. For the computation of the results, a segment (wavelength) of blood vessels about 120 mm with wave velocities in the range of 49 - 190 mm/sec are considered, where the diameter of BBVs ranges from 40-120 nm. The viscosity of the blood varies from 3.5-5.5 × 10-3Ns/m2 which affect the virion motion having a density range 1.03 - 1. 25 g/m3. RESULTS: It shows that the Hepatitis B virus is more harmful than other blood-borne viruses considered in the analysis. Patients with high blood pressure are highly susceptible for transmission of BBVs. CONCLUSIONS: The present fluid dynamics approach for virus spread through blood flow can be helpful in understanding the dynamics of virus propagation inside the human circulatory system.

Alteration in membrane-based pumping flow with rheological behaviour: A mathematical model.

BACKGROUND AND OBJECTIVE: Blood is complex fluids exhibits the non-Newtonian characters and rheological properties of the blood vary person to person. Typically, the rheological properties of blood are very similar to Carreau fluids which is considered in the present model. The main objective of this study is to examine how a typical membrane-based pumping model will function with varying rheological properties (shear-thinning, Newtonian, and shear-thickening) of fluids. METHODS: A mathematical formulation is constructed for the membrane-based pumping model using the conservation principles of mass and momentum, and stress-strain relationship based on Carreau fluids model. Velocity slip condition is adopted for this model to discuss the possibility of fluids velocity at the wall surface. The perturbation method is employed to derive the series solution for the governing equations subjected to physical boundary conditions with suitable assumptions. RESULTS: From numerical results, it is found that the pressure inside the microchannel reduces for the shear-thinning fluid and increases for the shear-thickening fluid with increasing the Weissenberg. In the membrane region, the chaos of the flow field is occurred due to the local pressure gradient by the rhythmic membrane propagation. It is further reported that shear-driven flow is responsible for the decrement in fluid velocity. CONCLUSIONS: This model provides a framework for estimating the effects of rheological properties and velocity slip for membrane-based pumping model which help in designing the smart pumps for various needs in the fields of biomedical engineering and fluid industries.

Propagation of H1N1 virus through saliva movement in oesophagus: a mathematical model.

H1N1 (Swine flu) is caused by the influenza A virus which belongs to the Orthomyxoviridae family. Influenza A is very harmful to the elderly, and people with chronic respiratory disease and cardiovascular disease. Therefore, it is essential to analyse the behaviour of virus transmission through the saliva movement in oesophagus. A mathematical paradigm is developed to study the saliva movement under the applications of transverse magnetic field. Jeffrey fluid model is considered for saliva to show the viscoelastic nature. The flow nature is considered creeping and assumptions of long wavelength and low Reynolds number are adopted for analytical solutions. The Basset-Boussinesq-Oseen equation is employed to understand the propagation of H1N1 virus through saliva under the effect of applicable forces such as gravity, virtual mass, basset force, and drag forces. The suitable data for saliva, oesophagus and H1N1 virus are taken from the existing literature for simulation of the results using MATLAB software. From the graphical results, it is observed that the susceptibility to viral infections is less because the magnetic field reduces the motion of the virus particle. Further, the chances of infections in males are more as compared to females and children due to variation in viscosity of saliva. Such findings provide an understanding of the mechanics of the virus floating through the saliva (viscoelastic fluids) in the oesophagus.

Bioinspired Pumping Flow Driven by Rhythmic Membrane Propulsion in a Porous Medium.

Investigation concerning the bioinspired pumping flow of viscous fluids in the porous region using Darcy's law is demonstrated in the present article. The rhythmic membrane contraction propels fluids in the porous microchannel. The periodic contraction of the membrane is utilized in the present analysis to introduce the unique pumping mechanism. For small pattern, width to channel height ratio (i.e., the channel is substantially longer than its width) and at low Reynolds numbers, the governing equations are solved by an analytical approach. In light of porous effects, we noticed the implications of rheological limitations on pumping and trapping processes. The porosity has a dynamic role in the augmentation of membrane-based pumping. These outcomes may be productive in various bioengineering (drug delivery schemes) applications.