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.

Galaxies form and evolve through close interaction with their surroundings. As a result, the heavy elements ('metals') that are synthesized in stars, are found both inside and outside galaxies.

Within the field of astronomy, understanding how galaxies grow and evolve from the Big Bang to the present day is a challenging and complex question.

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

This thesis discusses the physical and chemical processes than influence the composition of forming planets.

This thesis investigates how galaxies form and what diversifies the evolutionary histories of galaxies.

One of the key quests in astronomy is to study the growth and evolution of galaxies across cosmic time. Radio observations provide a powerful means of studying the formation of stars and subsequent buildup of distant galaxies, in a way that is unbiased by the presence of dust.

To address the fundamental questions of how life on Earth emerged and how common life may be in the Universe, it is crucial to know the chemical composition of the planet-forming material.

Promotores: Prof.dr. J. Schaye, Prof.dr. S.D.M. White (MPA Garching)

Promotor: J. Schaye

Promotor: R. Verpoorte, Co-promotores: Y.H.Choi, N.R. Mustafa

Promotor: Prof.dr. E.F. van Dishoeck

The focus of this thesis is how stars like our Sun and planets like Jupiter, Saturn, and Earth are formed.

Promotores: Prof.dr. W.J.G.M. Peijnenburg & Dr. M.G. Vijver

What is the effect of light at night on plant phenology and physiology, and how does this affect plant interactions with other species?

The studies described in this thesis deal with glycosidases, in particular alpha-galactosidases.

Promotor: Prof.dr. E. F. van Dishoeck

Wetenschappers bij de Leidse Sterrewacht onderzoeken de oorsprong van sterren en hun planetenstelsels. Ze detecteren en karakteriseren planeten rondom andere sterren (exoplaneten). Ze onderzoeken hoe sterren en planeten ontstaan. En ze volgen moleculen van interstellaire wolken tot planetenstelsels…

Promotor: C.A.M.J.J. van den Hondel, Co-promotor: Sandra de Weert

The formation of stars and planets happens over multiple scales, which can interact. In particular, planet formation happens in the dense, complex environment of star forming regions.

Promotor: P.G.L. Klinkhamer, Co-Promotores: K. Vrieling, P.P.J. Mulder

Promotor: Roeland M.H. Merks

Promotor: Prof.dr. E.F. van Dishoeck, Prof.dr. F.F.S. van der Tak (RUG)

Plants produce an astonishing variety of secondary metabolites (SMs) which are thought to play vital roles in the fitness of plants through ecological interactions.

Promotores: Prof.dr. T.H.W. Bäck, Prof.dr. M. Bongards (Cologne University)

Promotor: G.P. van Wezel

The soil ecosystem consists of the largest reservoir of biodiversity on Earth.

Promotor: E.F. Smets, Co-promotor: T.R. van Andel

This thesis investigates the relations between metabolism and anatomy through the use of Magnetic Resonance Imaging (MRI).

The solar system was formed approximately 4.56 billion years ago. Despite the numerous theories that have been developed over the years, the formation and evolution of the solar system still remain unclear.

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

Promotores: Prof.dr. M. Franx, Prof.dr. P.G. van Dokkum (Yale University)

Promotor: Prof.dr. L.J. Slikkerveer

Large areas of space are filled by molecular clouds that consist of gas and dust grains that are the remnants of dead stars. When these clouds start collapsing, the decreasing temperature and increasing density cause gas particles to start accreting onto dust grain surfaces.

A dense region of a gaseous and dusty cloud collapses to form a protostar surrounded by a disk and an envelope. This thesis uses both observations and models to study physical and chemical conditions of these protostellar systems which are likely where planets start to form.

Sobral

The origin and evolution of galaxies are closely tied to the cyclic feedback processes between stars and the interstellar medium (ISM).

Detecting planets during their formation stages is crucial for understanding the history and diversity of fully developed planetary systems like our own. However, observing young planets directly is challenging because they are often deeply embedded within their host protoplanetary discs, rich in gas…

Promotor: Prof.dr. H.V.J. Linnartz

What are trait-trait relationships in wetlands? To what extent the so-called leaf economics traits deviate from terrestrial ecosystems? How traits specific to wetland plant relate to plant strategies? What’s the relationship between wetland plant traits to the ecosystem functioning (e.g. productivity,…

It has been a long-standing mystery how complex biological structures emerge from such seemingly uncoordinated building blocks as cells and tissues, in the presence of only minimal environmental guidance.

Huub de Groot

This thesis takes steps toward understanding the interaction between gas-phase and solid-state molecules in star- and planet-forming regions.

This thesis aimed to investigate core cross-linked polymeric micelles (CCPMs) and expand their potential for the delivery of hydrophobic drugs and co-factors.

Following the Big Bang, structure in the Universe started collapsing under the force of gravity. This resulted in the formation of the first stars, galaxies and clusters of galaxies.

The Sundanese people, the largest ethnic group in West Java, have been using traditional medicine for a long time. Known as ubar kampung, Sundanese indigenous knowledge, beliefs and practices of traditional medicine are based on local people’s knowledge and use of Medicinal, Aromatic, and Cosmetic (MAC)…

Promotor: Erik F. Smets, Co-promotores: Barbara Gravendeel, Niels Raes

This thesis focusses on the temperature structure in protoplanetary disks. The relation between structures seen in the dust and gas-phase molecules is investigated.

Promotor: Prof.dr. E.F. van Dishoeck, Co-Promotor: M.R. Hogerheijde