A PhD position on modeling the flow behavior of blood cells and von Willebrand factor (VWF) in primary hemostasis (blood clotting) is available at the Theoretical Soft Matter and Biophysics group, Institute of Complex Systems (ICS-2) of Forschungszentrum Juelich, Germany. Our group works at the interface between physics, biology, and chemistry using computer simulations and analytical theory. This position is a part of the DFGResearch Unit FOR 1543 SHENC – Shear Flow Regulation in Hemostasis (http://www.shenc.de), which consists of a number of experimental and theoretical physics, and medical research groups, and aims at unravelling the regulatory role of shear stress in the VWF activation, VWF-mediated adhesion, and its degradation in primary homeostasis.

Primary hemostasis is a process initiated at a site of vascular injury leading to the formation of a blood clot in order to patch the opening. An important role in the blood clotting process is played by blood platelets and a large multimeric protein, the von Willebrand factor (VWF). Under normal conditions, VWF is present in blood (soluble) and endothelium (to be secreted) as a globular passive polymer. However, in case of vascular injury, secreted and soluble VWF is able to stretch under blood flow and bind to the site of injury. Wall-adhered VWF chains are able to bind flowing platelets, thus facilitating their firm adhesion and leading to a primary hemostatic plug, which resembles a network of VWF and platelets. This process can be dysfunctional for certain VWF mutations leading to bleeding complications or undesired thrombotic events. This PhD project will provide an opportunity to investigate the physical mechanisms of the primary hemostasis process in microcirculation using analytical theory and novel numerical methods.

Job description:
The new team member will be investigating the behavior and adhesion of the VWF in blood flow using the blood flow model developed in our group. Cell membranes are described as closed surfaces with curvature and stretching elasticity. The fluid-dynamics model is based on the dissipative particle dynamics (DPD) method, a mesoscale hydrodynamic simulation technique, and is implemented within a highly parallelized code. The PhD student will study adhesion of the VWF to endothelium and its interactions with platelets, under various blood flow conditions characteristic for microcirculation. In particular, he or she will be looking at the efficiency of VWF adhesion and platelet binding, at different concentrations of red blood cells and the rates of flow. The PhD student will also actively participate in the development of efficient algorithms and a parallel code to enable realistic simulations of the primary hemostasis process. A close collaboration with experimental groups within the SHENC consortium is expected in order to validate simulations, quantify experiments, and check new biophysical hypotheses.

Your profile:
- Strong motivation to study flow of complex fluids, and its physical mechanisms and processes.
- A master's degree or diploma in physics, biophysics, applied mathematics, chemistry, or a relevant engineering discipline.
- Good programming skills and experience with numerical modeling and particle-based methods. Motivation to develop new algorithms.
- Experience with parallel programming using MPI and high-performance computing resources is advantageous, but not necessary.

What we offer:
- Experienced and friendly international research team with a strong background in biophysics and blood-flow modelling.
- Cutting-edge computational facilities including the on-site top European supercomputers.
- Collaboration with the world's leading experimental groups on primary hemostasis.
- Three-year PhD program including a competitive salary and social benefits.
- Participation in the International Helmholtz Research School of Biophysics and Soft Matter (http://www.ihrs-biosoft.de) with a highly multidisciplinary environment.

Starting date:
January 2015 or later. Applications will be accepted until the position is filled.

How to apply:
Please send your application by email to Dr. Dmitry Fedosov (d.fedosov AT fz-juelich.de) including
- Curriculum Vitae.
- Motivation letter (a one page statement of your background and research interests).
- Copies of your university degree/s and grades.
- Contact information of two references.

Contact:
Dr. Dmitry Fedosov
Email: d.fedosov AT fz-juelich.de
Phone: +49(2461)-612972
URL: http://iffwww.iff.kfa-juelich.de/~fedosov/D_Fedosov.html
Forschungszentrum Juelich
Institute of Complex Systems (ICS-2)
Leo-Brandt Strasse
52425 Juelich…