The research groups within the biological, soft and complex systems research area study the physics of a broad range of biological and soft materials. This spans both experimental and theoretical research.

We study the physics of a broad range of biological and soft materials

Promotor: J.N. Kok, Co-Promotor: A.J. Knobbe

Complex systems can be characterized as systems in which multiple components interact with each other, often in non-linear ways. The main goal of this research will be to investigate if and how the international tax system can be defined and modelled as a complex system. Approaching the international…

Scientists often need to make sense of complex systems without knowing the important parameters or even without access to all the information. A collaboration of network theorists, including Diego Garlaschelli (IMT Lucca/Leiden), has now published a review article in the inaugural issue of Nature Reviews…

In this thesis, we extend the concept of null models as canonical ensembles of multi-graphs with given constraints and present new metrics able to characterize real-world layered systems based on their correlation patterns.

For many system in statistical physics the microcanonical and canonical ensemble are equivalent in the thermodynamic limit, but not for all.

The authors of the article expect automation to improve accuracy in less complex programmes but worsens with increased complexity

The financial system needs complexity theory to predict economic crises like the 2008 meltdown. An international team of scientists, including Leiden physicist Diego Garlaschelli, state this in a paper published in Science on February 19th.

The Systems Pharmacology group is headed by Prof. Piet Hein van der Graaf. Systems Pharmacology is the quantitative analysis of the dynamic interactions between drugs and a biological system to understand the behaviour of the system as a whole, as opposed to the behaviour of its individual constituents;…

In this thesis, we show that we can use Shimura’s CM theory to explicitly compute the Hilbert class field of any primitive quartic CM field.

For the first time, astronomers have detected the presence of complex organic molecules, the building blocks of life, in a protoplanetary disc surrounding a young star. The discovery reaffirms that the conditions that spawned the Earth and Sun are not unique in the Universe. The results are published…

Protein–protein complexes are formed via transient states called encounter complexes that greatly influence the formation of the stereospecific complex.

The thesis addresses the long-term dynamical evolution of hierarchical multiple systems.

What are the functions of the endocannabinoid system?

This thesis seeks to combine two different research topics; Multi-Objective Optimization and Complex Network Analysis.

What invertebrates are available to feed nestlings in an agricultural landscape of varied complexity?

The goal of the project is the development of stream mining techniques for complex patterns such as graphs. We will try to extend the existing state-of-the-art techniques into two, orthogonal directions: on the one hand, the mining of more complex patterns in streams, such as sequential patterns and…

Promotor: Peter Stevenhagen

Promotor: E. Bouwman, Co-promotor: S. Bonnet

Systems with local constraints is a new finding in recent researches on complex systems. The heterogeneous spatial interactions and the temporal dependencies among those numerous units make it difficult to describe by traditional statistical physics.

This thesis is comprised of three chapters covering the theme of studying semistable varieties by looking at their dual combinatorial objects.

Essays in Archaeology and Assyriology Dedicated to Diederik J.W. Meijer in Honour of his 65th Birthday

Stars like the sun are born in large molecular clouds existing from gas and dust. During the formation process, the chemical composition of the material can be altered drastically by the changing physical conditions.

Molecular complexes can be used as electrocatalysts for oxygen reduction, water oxidation, and/or hydrogen peroxide production.

In photoactivated chemotherapy (PACT), a biologically active compound is caged by a light-cleavable protecting group.

The Leiden Complex Networks Network (LCN2) aims at bringing together scientists from different disciplines, based on a common interest in both theoretical models and empirical analyses of networks and graphs.

Matthias de Vrieshof, Matthias de Vrieshof 1-4, 2311 BZ, Leiden

Conference

This thesis describes the genetic and prokaryotic diversity of giant barrel sponges.

Issues such as climate change, the depletion of natural resources or social inequality are too complex to be addressed from a single scientific discipline or by a single country. Leiden University has the expertise to bring the resolution of these enormous problems a small step closer.

Light-Harvesting Complex II (LHCII) is responsible for light absorption and excitation energy transfer in plants and photosynthetic algae, while in high light it undergoes conformational changes by which it quenches excitations to prevent photodamage.

The Computer Systems, Imagery & media (CSI) research programme performs research on methods and techniques for the design, implementation and application of advanced computer systems, in particular parallel, distributed and embedded computer systems.

The complexity of an intelligence problem determines to a great extent the certainty that can be provided by intelligence and security services.

In vitro disease models play a fundamental role in drug research. They enable the systemic identification and validation of disease mechanisms and the discovery of possible drug targets. However, more than often, drug candidates that are identified in vitro fail in the later clinical stages of drug…

In this thesis, the researcher developed a nanosystem based on the metallophilic Interaction between cyclometalated complexes.

Promotor: E. Bouwman Co-Promotor: S. Bonnet

The Collective Experience of Empathic Data Systems (CEEDs) consortium developed novel integrated technologies that support experiencing, analysing and understanding of very large datasets.

Promotor: J.N. Kok, Co-promotor: H.J. Hoogeboom

Systems are called real-time systems, if the correctness of the system does not only depend on the correctness of the system output but also on whether the output is delivered on time.

Promotors: W. Jiskoot; G.J. Witkamp, Co-promotor: M.R. Nejadnik

Calamus javensis is polymorphic. Morphometry and molecular approach resulted in all names used in the complex are regarded as synonyms of C. javensis except C. tenompokensis, which is retained as a distinct species. One variety is here recognized, C. javensis var. polyphyllus (including C. acuminatu…

Promotor: C. W. J. Beenakker, Co-promotor: J. K. Asboth

From surface science towards industrial practice using high-pressure scanning tunneling microscopy.

Mathematical models of software systems enable characterizations, abstractions, simulations, and analysis of complex software during its development.

In this thesis, a system pharmacology approach, integrating metabolomics, pharmacology and chemical biology, was applied to understand and modulate the endocannabinoid system across different model systems (cells, zebrafish, mice and humans).

Hetterscheid

This project develops methods for ensuring the anonymity of individuals in social network data.

The aim of this project is to determine in which cases uncertainty statements resulting from a Bayesian statistical analysis can be trusted.