Igor Pivkin

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Mural thrombi are composed dominantly of platelets and develop under a blood flow. Portions can break off and are carried in the blood flow as emboli. Thrombus growth rates are affected by the velocity of the blood flow, but they do not simply increase with it, they exhibit a maximum, with subsequent decrease. Whereas this variation indicates an interaction(More)
Dissipative particle dynamics (DPD) is a potentially very effective approach in simulating mesoscale hydrodynamics. However, because of the soft potentials employed, the simple no-slip boundary conditions are difficult to impose. In this work, we first identify some of these difficulties and subsequently we propose a new method, based on an equivalent force(More)
Malaria resulting from Plasmodium falciparum infection is a major cause of human suffering and mortality. Red blood cell (RBC) deformability plays a major role in the pathogenesis of malaria. Here we introduce an automated microfabricated "deformability cytometer" that measures dynamic mechanical responses of 10(3) to 10(4) individual RBCs in a cell(More)
We study the biomechanical interactions between the lipid bilayer and the cytoskeleton in a red blood cell (RBC) by developing a general framework for mesoscopic simulations. We treated the lipid bilayer and the cytoskeleton as two distinct components and developed a unique whole-cell model of the RBC, using dissipative particle dynamics (DPD). The model is(More)
This paper presents a case study of interdisciplinary collaboration in building a set of tools to simulate and visualize airflow around bat wings during flight. A motion capture system is used to generate 3D coordinates of infrared markers attached to the wings of a bat flying in a wind tunnel. Marker positions that cannot be determined due to high wing(More)
Dissipative Particle Dynamics (DPD) simulations of wall-bounded flows exhibit density fluctuations that depend strongly on the no-slip boundary condition and increase with the level of coarse graining. We develop an adaptive model for wall-particle interactions that eliminates such oscillations and can target prescribed density profiles. Comparisons are(More)
Dissipative particle dynamics (DPD) simulations are employed to study the shape transformations of vesicles formed from amphiphilic triblock copolymers. The amphiphilic molecule is built from two different hydrophilic blocks on the sides and a hydrophobic block in the middle. To model the asymmetric membrane in the vesicle, spontaneous curvature is(More)
Dissipative particle dynamics (DPD) is a relatively new mesoscopic simulation approach , which has been successfully applied in modeling complex fluids in periodic domains. A recent modification [1] has allowed DPD simulations of polymers for realistic values of the Schmidt number. However, DPD and its extensions encounter difficulties in simulating even(More)
A three-dimensional model with simplified geometry for the branched coronary artery is presented. The bifurcation is defined by an analytical intersection of two cylindrical tubes lying on a sphere that represents an idealized heart surface. The model takes into account the repetitive variation of curvature and motion to which the vessel is subject during(More)