The University of Helsinki annually acknowledges doctoral dissertations of outstanding merit. In addition to scientific merit, the award grounds take into account the impact of the work in the relevant scientific field, as well as its social impact, if any.
The chosen dissertations investigated combinatorial optimisation problems, new kinds of nanoparticle systems intended for targeted drug delivery, the changes inside trees during the formation of heartwood, and the tax planning conducted by multinational corporations.
Recipients of the University of Helsinki doctoral dissertation awards 2018
Jeremias Berg, DPhil: Solving Optimization Problems via Maximum Satisfiability: Encodings and Re-Encodings
Mónica Ferreira, Dsc (Pharmacy): Multifunctional Nanoparticles for Targeted Drug Delivery and Imaging for Ischemic Myocardial Injury
Tanja Paasela, DPhil: The Stilbene Biosynthetic Pathway and Its Regulation in Scots Pine
Matti Ylönen, DSocSci: Planned Economies? Corporations, Tax Avoidance and World Politics
The awards for 2018, each worth €4,000, were conferred at a celebration organised at the University of Helsinki on 6 May 2019.
Top-level dissertation provided solutions for optimisation problems
In his doctoral dissertation entitled Solving Optimization Problems via Maximum Satisfiability: Encodings and Re-Encodings, Jeremias Berg, PhD, developed methods for solving challenging combinatorial optimisation problems.
A combinatorial optimisation problem is a general term for problems where the aim is to find the best solution from among a predetermined set of feasible solutions, such as the shortest or most inexpensive one. These kinds of problems occur in a number of scientific and industrial fields. For instance, many problems relating to machine learning can be presented as combinatorial optimisation problems.
Effective methods for solving optimisation problems can save time, money and other resources in various applications. Berg’s dissertation focuses on developing declarative methods for solving combinatorial optimisation problems.
“A declarative method uses a constraint model to describe the instance of an optimisation problem to be solved, making the same solution algorithms available for solving many different optimisation problems,” Berg explains.
The dissertation provides new pre-processing methods and constraint models for two optimisation problems related to machine learning, with a focus on Maximum Satisfiability (MaxSAT), the extension of the Boolean satisfiability problem (SAT) to optimisation.
Berg’s research is at the top of the field, significantly advancing the theory of MaxSAT methods while proposing related practical applications. The articles included in the dissertation have been published in the most distinguished journals in the field, gaining a number of citations.
Nanosystems based on porous silicon and dextran may be a starting point to develop nanomedicines that can be applied in the treatment of myocardial infarction
In her dissertation entitled Multifunctional Nanoparticles for Targeted Drug Delivery and Imaging for Ischemic Myocardial Injury defended at the Faculty of Pharmacy, Mónica Ferreira, Ph.D. (Pharmacy), developed novel nanoparticle systems that can be used to target the delivery of drugs and facilitate imaging for cardiac ischemic injury.
The persisting lack of an effective method for restoring the function of an injured heart served as an impetus for the research. Current forms of treatment do improve the care of patients suffering from myocardial infarction and heart failure, but there is great demand for medical therapies for diseases of cardiac origin. Therapies based on nanoparticles show promise, as they can be precisely targeted and do not necessitate highly invasive surgical procedures.
Ferreira’s dissertation developed and investigated new kinds of nanoparticle systems suitable for drug delivery based on porous silicon and spermine-acetalated dextran.
The dissertation has provided significant new information on the application potential of nanoparticle technologies in treating myocardial infarction. The targeted nanoparticles described in the dissertation can be modified to reach their destination in injured tissues or cells as effectively as possible.
In 2018 Ferreira was presented with the distinguished Albert Wuokko Award for junior scholars in pharmacy for her research.
Tracking natural decay resistance
In her doctoral dissertation entitled The Stilbene Biosynthetic Pathway and Its Regulation in Scots Pine, Tanja Paasela, DPhil, investigated the formation of heartwood and the effect of genes on the production of stilbene.
Wood breeding is increasingly focused on advancing quality characteristics alongside accelerating growth. Paasela’s dissertation investigated stilbenes, which influence the decay resistance of the heartwood in Scots pine, an important quality characteristic. Stilbenes are also involved in the active defence responses of pines.
Based on the results, it is increasingly apparent that heartwood formation is an internally regulated process, not something triggered by environmental factors. The single most significant finding in the dissertation was a gene that regulates stilbene production (PMT2).
“Climate change is bringing new pathogens and pests to Finland, which increases the importance of plant resistance. The genetic findings gained in the dissertation can hopefully be utilised in improving the decay resistance of pine through breeding. In further studies, we are looking into whether there are differences between the individual genes we identified, something which could explain the differences in stilbene content,” Paasela says.
Paasela’s research has notable scientific significance to basic research in plant biology, forestry and functional genetics. In addition to its merits in basic research, the dissertation may have a far-reaching impact in the wood industry and commercial forestry. Research on new purposes of use for wood is currently very active, while solutions to replace petroleum-based plastics are looked for in wood material. Furthermore, the utilisation of wood extractives as antioxidants in food is being researched. The enzyme that methylates stilbene identified in this study may also be needed in modifying extractives to make new commercial products.
Corporate tax planning is also a question of global politics
In his doctoral dissertation titled Planned Economies? Corporations, Tax Avoidance and World Politics, Matti Ylönen (DSocSci) made several new contributions for understanding the political aspects of corporate tax planning and its governance. The ease at which large multinational enterprises can shift their profits between countries gives them significant power over governments, in addition to creating opacity.
The article-based dissertation approached this thematic by focusing on the political economy of multinational enterprises and their governance, while also providing new analytical tools for understanding corporate power. One of the articles co-authored by Ylönen and professor Teivo Teivainen was awarded the Amartya Sen Prize by Yale University in 2015.
The dissertation contributes to several topical policy discussions. An article co-authored with tax researcher Lauri Finér analyzed tax planning structures that have been utilized by Canadian mining companies in Finland: this article and a report that preceded it have had an important role in steering the debate on mining taxation in Finland. The dissertation also assesses the proposals made for example by the city of Helsinki on introducing transparency- and tax-related criteria to public procurement tenders. An article focusing on this thematic has contributed to a Europe-wide discussion on the need to reform the EU’s procurement directive.
“The dissertation highlights the surge of multidisciplinary research on political economy in Finland. New ideas always come about through cooperation, and Helsinki is emerging as an interesting hub for this kind of research”, Ylönen notes.