Alfons Hoekstra’s research focuses on modelling and simulating complex systems, with an emphasis on multiscale models of human physiology and pathology. He helped to create the‘Virtual Physiological Human’ and contributed to the ‘Virtual Artery’, a multiscale model of the cardiovascular system. The latter includes both low-dimensional models of systemic blood flow and highly detailed models in which all individual red and white blood cells and platelets are modelled in plasma suspension. 

Hoekstra additionally develops models of the arterial wall which explicitly include the behaviour of specific cells, such as smooth muscle cells. He then applies these models to cases such as thrombosis, intracranial aneurysms and arterial tissue reactions to stenting. Hoekstra also develops methods and techniques for simulating these complex multiscale models on the most powerful supercomputers. He has worked in close collaboration with international computing centres to create the ‘Multiscale Modelling and Simulation Framework’. 
Alongside his research, Hoekstra teaches several courses in the Master’s programme in Computational Science. 

The virtual physiological human

As a professor, Hoekstra will focus on various applications of the ‘Virtual Physiological Human’. As a researcher, he will concentrate on in silico trials (using computer calculations) for coronary stents and acute cerebral infarction, and fundamental and applied research into haemostasis and thrombosis. His research work will additionally focus on models for human physiology and pathology in the elderly, as well as models which explicitly take into account the impact of socio-economic environmental factors and psychological factors on health and disease. Hoekstra will also continue to investigate how such multiscale models can be efficiently simulated on the most powerful supercomputers in the world, and how this computing power can be used to calculate the impact of uncertainties in these multiscale models and the model parameters on the final result of the simulation. This concept of multiscale ‘uncertainty quantification’ is still in its infancy and will be an important topic of research in the years ahead.

About Alfons Hoekstra

Hoekstra has been affiliated with the UvA’s Informatics Institute since 1990, where he has served as an associate professor since 2002. Hoekstra is a member of the institute’s management team and head of the Computational Science Lab. From 2003 until 2007, he was the programme director of the Bachelor’s in Computer Science. He also helped to establish the Master’s in Computational Science. In 2014, Hoekstra was named Professor of Computational Biomedicine at ITMO University in St. Petersburg, Russia.

He is project director of several large European projects. Hoekstra was additionally involved in the film ‘Virtual Humans’, which shows the possibilities of using high-performance computing (HPC) to delve deeper into the processes that take place in the human body.Virtual Humans was produced as part of the CompBioMed project.Hoekstra is editor of the Journal of Computational Science.