Normal haemostasis is an important physiological mechanism that prevents excessive bleeding during trauma, whereas the pathological thrombosis especially in diabetics leads to increased incidence of heart attacks and strokes as well as peripheral vascular events. In this work, we propose a new multiscale framework that integrates seamlessly four key components of blood clotting, namely transport of coagulation factors, coagulation kinetics, blood cell mechanics and platelet adhesive dynamics, to model the development of thrombi under physiological and pathological conditions. We implement this framework to simulate platelet adhesion due to the exposure of tissue factor in a three-dimensional microchannel. Our results show that our model can simulate thrombin-mediated platelet activation in the flowing blood, resulting in platelet adhesion to the injury site of the channel wall. Furthermore, we simulate platelet adhesion in diabetic blood, and our results show that both the pathological alterations in the biomechanics of blood cells and changes in the amount of coagulation factors contribute to the excessive platelet adhesion and aggregation in diabetic blood. Taken together, this new framework can be used to probe synergistic mechanisms of thrombus formation under physiological and pathological conditions, and open new directions in modelling complex biological problems that involve several multiscale processes.

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An extended Taylor cone-jet mode is experimentally characterized using a recently introduced hemispherical nozzle. Ethanol is used as the working fluid, and the nozzle produces a much broader range of flow rate and stability of the cone-jet mode. High-resolution images are captured using a high-power light-emitting diode in precise lighting operations to characterize the liquid behavior. Various regimes in the extended cone-jet mode are recognized and mapped in a plane of electro-Weber and Bond numbers. The cone profiles are quantified regarding dimensionless groups, and a related self-similarity is introduced. The cone elongates with the electro-Weber number but retracts as the Bond number increases. The cone and jet diameters are also quantified from the nozzle exit to where the jet begins a transition to instability. It is shown that jet diameter increases with the electro-Weber number powered by 0.75, but it is independent of the Bond number. The meniscus lengths are reported at different electro-Weber and Bond numbers too, and the corresponding correlations are obtained. Finally, jet whipping and spray envelopes are illustrated at various dimensionless numbers, while a wider spray envelope and a dual distribution are recognized at higher electro-Weber numbers.

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The crucial role of hemorheological characteristics of blood in a range of diagnoses, treatments and drug delivery mechanisms is widely accepted. Nonetheless, the literature on blood rheology remains inconclusive and...