Ice, the solid state of water, plays an important role on our planet as well as the entire universe.Despite the fact that an individual water molecule has a very simple structure, its chemical bonding in the solid phase can be surprisingly complex.

Promotor: T. H. Oosterkamp

Promotor: R. Tijdeman, Co-promotor: H.J.J. te Riele

The invention of neural networks marks a critical milestone in the pursuit of true artificial intelligence. Despite their impressive performance on various tasks, these networks face limitations in learning efficiently as they are often trained from scratch.

Promotores: S.F. Portegies Zwart, E. M. Rossi

Hydrodesulfurization (HDS) is an ubiquitous part of oil refining that ensures that fuels are cleaned of impurities and environment release of pollutants such as SOx and NOx gasses are minimized.

Metals surfaces form a group of effective catalysts for the reaction of small molecules such as hydrogen (H2).

In condensed matter systems electron-electron interactions, negligible in everyday metals, can dramatically alter the electronic behavior of the system. Examples of such altered behavior include high-temperature superconductivity and modulation of the electron density.

Humanity stands at a pivotal juncture, facing the dual challenge of environmental sustainability and rapid population growth, projected to exceed 11 billion by century’s end.

Promotor: V. Vitelli, Co-promotor: J. Paulose

It is a common technique in global optimization with expensive black-box functions to learn a surrogate-model of the response function from past evaluations and use it to decide on the location of future evaluations.

The lipid membrane is a basic structural component of all living cells. Embedded in this nanometer-thin barrier, membrane proteins shape the membrane and at the same time respond to the shape of the membrane.

Quantummechanica voor iedereen

In summary, the collective results described in this thesis show that nanoparticulate vaccines can be delivered intradermally by coated and hollow microneedles and evoke antigen-specific immune responses.

Carbonaceous asteroids preserve a record of early solar system processes, where minerals and organic molecules, like polycyclic aromatic hydrocarbons (PAHs), offer clues to planetary evolution and prebiotic chemistry.

Promotor: Prof.dr. J.M. van Ruitenbeek, Prof.dr. R.M. Tromp

For optimization problems, it is often unclear how to choose the most appropriate optimization algorithm. As such, rigorous benchmarking practices are critical to ensure we can gain as much insight into the strengths and weaknesses of these types of algorithms.

This thesis explores the theoretical and observational properties of distant massive galaxies that harbour active black holes in their centres and shine brightly at radio wavelengths.

While ecosystems have concrete benefits for human society, these benefits are typically overlooked in decision-making.

Promotor: J.A. Bouwstra Co-promotor: A. El Ghalbzouri

Multiple stars, that is two or more stars composing a gravitationally bound system, are common in the universe.

Dark matter is one of the biggest mysteries of the Universe. Its properties cannot be explained with the known laws of physics and elementary particles.

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Astronomical observations of cold regions in the universe show a rich inventory of ices. Part of these ices may end up on planets like our own, but in that journey they will be exposed to considerable amounts of radiation.

Plants and their pollinators form complex interaction networks. Within these networks, species differ widely in the number of species they interact with.

High-angular-resolution observations of the circumstellar material have uncovered numerous and very diverse substructures in protoplanetary discs, raising the question of whether they are caused by forming planets or other mechanisms.

Phospholipase A/acyltransferase 3 (PLAAT3) and PLAAT4 are enzymes involved in the synthesis of bioactive lipids. Despite sequential and structural similarities, the two enzymes differ in activity and specificity.

There is concern about the threat that nanoplastics (NPs) may pose to both wildlife and humans. This thesis explores the mechanisms of toxicity of polystyrene nanoparticles (PS-NPs) in chicken embryo.

All life on earth contains DNA, which is used to store biological information. Organisms compact their DNA in order for it to fit inside their cell(s).

Promotor: P.D. Grünwald

Vancomycin is a last-resort antibiotic for the treatment of many Gram-positive bacterial infections, while remaining inactive against Gram-negative strains.

This thesis considers multi-prover commitment schemes whose security is based on restrictions on the communication between the provers.

Promotor: W.Th.F. den Hollander Co-Promotor: F.M. Spieksma

The overarching goal of this thesis is to set the foundations, but also make the first essential steps towards establishing a comprehensive, mesoscopic, hydrodynamic theory of epithelial tissues. The stage is set by an exhaustive study of topological defects in passive p-atic liquid crystals, singularities…

Outflows are crucially important for the gas budget and evolution of luminous star-forming galaxies and AGNs, with observed mass outflow rates of the same order as the star formation rate. Greater star formation and black hole growth lead to more intense feedback and outflows, resulting in self-regulated…

Mining time series is a machine learning subfield that focuses on a particular data structure, where variables are measured over (short or long) periods of time.

Streptomyces are filamentous bacteria that produce more than two-thirds of known antibiotics.

This dissertation studies the Asymptotics of Bayesian nonparametric inference for Gaussian linear models.

Promotores: T.H.W. Bäck, Y. Tan, Co-promotor: M.T.M. Emmerich

In this thesis unconventional tools based on fluidic interfaces were developed to study the surface and interfacial chemistry of graphene, to characterize the intrinsic properties of graphene, to disentangle the effects of substrate and of the environmental factors, and to improve handling protocols…

This thesis addresses the chemical processes that determine the compositions of giant planet atmospheres.

Promotores: H.A. Udo de Haes, H.H.T. Prins, Co-promotor: H.H. de Iongh

Promotores: H. Schiessel, G.T. Barkema

Promotor: Prof.dr. E. Eliel, Co-Promotor: M.J.A. de Dood

Even though more than 4000 extra-solar planets are known today, only a small fraction of these has been captured in an image. To better understand the planet formation mechanisms in solar-like environments we started the Young Suns Exoplanet Survey (YSES).

In the first part, we introduce a new condition, called toric-additivity, on a family of abelian varieties degenerating to a semi-abelian scheme over a normal crossing divisor.

By training with virtual opponents known as computer generated forces (CGFs), trainee fighter pilots can build the experience necessary for air combat operations, at a fraction of the cost of training with real aircraft.

This work is dedicated to interpreting in cohomological terms the special values of zeta functions of arithmetic schemes.

The plant hormone auxin regulates plant growth and development through polar cell-to-cell transport-generated maxima and minima. PIN FORMED (PIN) auxin efflux carriers determine the direction of this auxin flow through their asymmetric placement on the plasma membrane (PM).

In this work, we attempt to answer the question: