A single-particle mechanofluorescent sensor

Monitoring mechanical stresses in microchannels is challenging. Herein, we report the development of a mechanofluorescence sensor system featuring a fluorogenic single polydiacetylene (PDA) particle, fabricated using a co-flow microfluidic method. We construct a stenotic vessel-mimicking capillary channel, in which the hydrodynamically captured PDA particle is subjected to controlled fluid flows. Fluorescence responses of the PDA particle are directly monitored in real time using fluorescent microscopy. The PDA particle displays significant nonlinear fluorescence emissions influenced by fluid viscosity and the presence of nanoparticles and biomolecules in the fluid. This nonlinear response is likely attributed to the torsion energy along the PDA's main chain backbone. Computational fluid dynamic simulations indicate that the complete blue-to-red transition necessitates ~307 μJ, aligning with prior research. We believe this study offers a unique advantage for simulating specific problematic regions of the human body in an in vitro environment, potentially paving the way for future exploration of difficult-to-access areas within the body.

Effects of porosity in four-layered non-linear blood rheology in constricted narrow arteries with clinical applications

BACKGROUND AND OBJECTIVE

This study aims to investigate the haemodynamical factors with the motive to spell out some useful information for better interpretation and treatment of cardiovascular diseases. Numerous researchers theoretically investigated the movement of blood in the vascular system, treating blood as either single-layered or two-layered fluid representation. In this contemporary study, a four-layered fluid model is developed to analyse the rheological elements of blood when it flows via constricted arteries with slight constriction and the arterial wall is considered as porous medium.

METHODS

The momentum and constitutive equations are solved together with the suitable boundary conditions in an attempt to get the results on the distribution of velocity, volumetric flow rate, pressure gradient, shear stresses at the wall and resistive impedance to flow in which methods of integration and perturbation are utilized. The analytical/numerical solutions and graphical results are obtained by the extensive use of MATLAB software.

RESULTS

It is of importance to state that the magnitude of the shear stresses on the wall reduces with the rise of Darcy number, Weissenberg number and power law index. Velocity of blood however, rises with the upsurge in Darcy slip parameter, Weissenberg number and power law index. It is pertinent to record that when the stenosis depth rises from 0 to 0.15, the ratio of increase in the mean velocity of healthy, anemic and diabetic subjects are recorded as 4.58, 2.62 and 22.44 respectively. It is also found that the ratio of increase in the wall shear stress in the aforementioned states of blood are found to be 4.7, 4.27 and 3.62 respectively when the stenosis depth rises from 0 to 0.15.

CONCLUSION

The nature of increased flow resistance in all three different situations such as anemic, healthy, and diabetic shows that the larger the constriction in the artery, the less amount of blood is transported to crucial organs which results in the sudden death of subjects. It is hoped that the outcomes of this study would be useful to medical practitioners and bio-medical engineers in predicting the behavior of blood flow in narrowed blood vessels for a more probable treatment modalities.

A significant role of permeability on blood flow for hybrid nanofluid through bifurcated stenosed artery: Drug delivery application

OBJECTIVE

The prime objective of concerned article is to discuss the permeability impacts on blood flow by considering hybrid nanofluid through bifurcated stenosed artery.

DESIGN/APPROACH

The human body circulatory framework involves the arrangement of veins that fuse the bifurcation on parent, at apex and on regions of daughter artery with nanoparticles is viewed. Blood streaming is recognized as Newtonian along vessel segment. The walls of the stenosed bifurcated artery is considered to be permeable as well as compliant. Copper and its oxide as used as drug to minimize the stress and the lesions of the atherosclerotic artery.

FINDINGS

The theoretical investigation is carried out by invoking the experimental values of hybrid nanoparticles into the structured equations. Moreover, impacts of hemodynamics are also make sense of to inspect the progression of blood for atherosclerotic vein. Daughter and parent artery comparison is described through parabolic graph of velocity. Graphical illustration is utilized to present the theoretical results of this drug delivery model. Metallic nanoparticles justify their use in drug delivery.

CONCLUSIONS

The flow of blood is viewed as not quite the same as pressure between segments of atherosclerotic and non-atherosclerotic course. Bifurcation angle minimize the stress for daughter artery whereas trend is opposite for parent daughter. The change in compliant wall parameter reduces the circulating bolus size for parent daughter whereas for daughter artery the change in bolus shape is observed.

Numerical Investigation of Oxygenated and Deoxygenated Blood Flow through a Tapered Stenosed Arteries in Magnetic Field

Current paper is focused on transient modeling of blood flow through a tapered stenosed arteries surrounded a by solenoid under the presence of heat transfer. The oxygenated and deoxygenated blood are considered here by the Newtonian and Non-Newtonian fluid (power law and Carreau-Yasuda) models. The governing equations of bio magnetic fluid flow for an incompressible, laminar, homogeneous, non-Newtonian are solved by finite volume method with SIMPLE algorithm for structured grid. Both magnetization and electric current source terms are well thought-out in momentum and energy equations. The effects of fluid viscosity model, Hartmann number, and magnetic number on wall shear stress, shearing stress at the stenosis throat and maximum temperature of the system are investigated and are optimized. The current study results are in agreement with some of the existing findings in the literature and are useful in thermal and mechanical design of spatially varying magnets to control the drug delivery and biomagnetic fluid flows through tapered arteries.