This dissertation presents new cryptographic protocols, which can be divided into two families.

The Standard Model (SM) of particle physics fails to explain several observed phenomena and is incomplete. In order to resolve this problem, one may extend the SM by adding new particles.

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

Until the 1990s, the only known planets were those in our Solar System. Three decades later, several thousand exoplanets have been discovered orbiting stars other than the Sun, and substantial efforts have been made to explore these strange new worlds through spectroscopic analyses of their atmosphe…

Promotores: P. Stevenhagen, E. Fouvry (Univeriste Paris Saclay)

This proposed research uses ego-documents from visual artists that were not intended for publication to reassess the scholarly debate on the demise of the Russian Avant-garde aesthetic in the twenties and early thirties of the 20th century.

Low-mass main-sequence stars like our Sun are continuous sources of outflowing hot magnetised plasma. In the case of the Sun, this is known as the solar wind, whereas for other stars they are called stellar winds.

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.

Promotor: Jaap Brouwer, Co-promotor: Remus Th. Dame

Marine sponges are important members of reef ecosystems, as they play ecological roles that are essential for the health of the reef.

Glycoside hydrolases (glycosidases/GHs) are widely abundant enzymes in all kingdoms of life and are important biocatalysts that catalyze the hydrolysis of glycosidic linkages in oligo/polysaccharides, glycoproteins and glycolipids with tremendous efficiency

Science is typically a patchwork of research contributions without much coordination. Especially in clinical trials, the follow-up studies that we do fail to be the most promising.

Promotores: G. Persoon, R. Schefold

Plants are colonized by an astounding number of microorganisms that can provide different life-support functions, including nutrient acquisition and protection against (a)biotic stresses like drought or pathogen attack.

Natural resources often stretch across borders that separate modern nation states. This can create conflict and limit opportunities for regulated consumption of their goods and services, but also provide opportunities for joint multinational efforts that exceed single country capabilities.

One of the main challenges in the development of an effective anti-cancer vaccine is the generation of an adequate and directed cellular immune response.

Streptomyces are bacteria abundant in soil that participate in diverse and complex interactions. These bacteria are the main producers of the antibiotics we currently use in the clinic.

Technologies that help to enhance our educational environments can be found everywhere.

In today's volatile market environments, companies must be able to continuously innovate. In this context, innovation does not only refer to the development of new products or business models but often also affects the entire organization, which has to transform its structures, processes, and ways of…

Human language is constantly evolving with its linguistic structure being shaped by language users at both individual and population levels. Focusing on the interplay between processes of language acquisition and communicative need in shaping human languages, this thesis introduces a novel computational…

Internationale wetenschappelijke consortia zijn steeds belangrijker binnen de wetenschap. Ze staan tegenwoordig vaak centraal bij de aanpak van mondiale vraagstukken op het gebied van gezondheid, milieu en schone energie. Ze kennen echter ook unieke uitdagingen. Om die in kaart te brengen, ontving hoogleraar…

Hoogleraar theoretische chemie Geert-Jan Kroes krijgt een prestigieuze Advanced Grant van de European Research Council (ERC). Met de bijbehorende 2,5 miljoen euro wil Kroes nauwkeurig modelleren hoe gasmoleculen reageren op metaaloppervlakken. Met die fundamentele kennis kunnen veel chemische stoffen…

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

This thesis aims to improve the detection from ultra-weak single emitter by enhancing their emission properties with plasmonic nanostructures. We exploit the wet-chemically synthesized single crystalline gold nanorods (GNRs) as our basic frameworks in the whole studies, simply because of their unique…

n this PhD thesis, the recombination of different atomic lattices in stacked 2D materials such as twisted bilayer graphene is studied. Using the different possibilities of Low-Energy Electron Microscopy (LEEM), the domain forming between the two atomic layers with small differences is studied.

One of the key limitations of the direct imaging of exoplanets at small angular separations are quasi-static speckles that originate from evolving non-common path aberrations (NCPA) to which the primary adaptive optics system is inherently blind. The main focus of this thesis is the development and…

In this thesis, we show how MRFM can usefully contribute to the field of condensed-matter.

During my PhD research, I studied the photon statistics of light emitted by a microcavity that contains a single quantum dot (QD) on resonance.

Promotor: Christoph U. Keller, Co-promotores: Matthew A. Kenworthy, Frans Snik

The elementary excitations of magnets are called spin waves, and their corresponding quasi-particles are known as magnons. The rapidly growing field of Magnonics aims at using them as information carriers in a new generation of electronic devices, (almost) free of electric currents.

We find ourselves in an era of transition, not just towards a more computing- and data-driven society but also away from unsustainable fossil fuels as an energy source.

Promotor: D. Bouwmeester, Co-promotor: D. Kraft

Surface plasmons (SPs) are surface waves at the interface between a dielectric and a good metal, and are formed by the interaction between light and the free electrons at the metal-dielectric interface. They provide strong field confinement for optical fields, opening new possibilities for enhanced…

This thesis presents insights from our study of various correlated electron systems with a scanning tunneling microscope (STM). In ordinary metals, electron-electron interactions exist, but get substantially screened due to the sheer number of electrons.

The thesis describes the use of electron paramagnetic resonance (EPR) spectroscopy, in continuous wave and pulse modes, to address the interaction of α-Synuclein (αS) with membranes and the aggregation of αS.

In this thesis, we develop a novel technique called Optical Near-field Electron Microscopy (ONEM), which aims to combine the advantages of both optical and electron microscopy: the high resolution of electron microscopy and the low sample damage of optical microscopy.

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.

Ben Wielstra wil de evolutie van gebalanceerde systemen van dodelijke allelen ontrafelen. Op 1 februari startte hij daarom zijn eigen laboratorium aan het Insituut voor Biologie Leiden. Wielstra is één van de vijf onderzoekers van de Universiteit Leiden die in 2018 een ERC-startsubisidie heeft ontvangen…

Onderstaand een overzicht van alle vakken die door de afdeling Economie worden verzorgd.

De onderzoeksgroep Cyber Security Governance bestudeert de impact van moderne technologie op governance, soevereiniteit, wetshandhaving en internationale betrekkingen, en levert toonaangevend academisch onderzoek en beleidsinzichten.

Climate change is a challenge for both current and future generations. New biological resources have to be developed in order to meet the demand for energy as well as the demand for food.

In this project of the Center for Public Values & Ethics (CPVE) ongoing research is conducted on the history of advice to Dutch central government by so-called State committees from 1814 to 2014. State committees have been installed by Dutch central government since 1814 to provide expert advice, research…

In het academisch jaar 2023-2024 biedt het interdisciplinaire onderzoeksprogramma Sociale Veerkracht en Veiligheid vier vakken aan voor studenten die beginnen met het derde jaar van hun bachelor. Deze vakken zijn te volgen binnen de ruimte voor keuzevakken. Je kunt de vakken afzonderlijk als keuzevak…

Breeding for resistance becomes more and more important because we want to reduce the use of pesticides. A fast and cheap alternative can be to make use of morphological or chemical markers.

In order to be able to develop effective medicine and treatments to prevent or cure autoimmune diseases or cancer we need to understand the mechanisms how they arise and what drives their course.Unravelling the fundamental molecular mechanisms influencing the onset and course of diseases such as allergies,…

In-use stocks of products can be considered as intermediaries between human needs and the physical world.

Promotor: M. Franx, Co-Promotor: I.F. Labbé

In analogy to mathematical proofs, the goal of a proof system is for a prover to convince a verifier of the correctness of a claim.

The endophytic microbiota is a community of various microorganisms that reside in plant tissue. These microbes are known to promote plant health and resilience, and their members do not simply exist side by side.

Ontdek de uitzonderlijke prestaties en bijdragen van onze academici en onderzoekers, die nationale en internationale erkenning hebben ontvangen voor hun werk in diverse geesteswetenschappelijke disciplines. Leer meer over hun invloedrijke onderzoek en impact binnen de academische gemeenschap en daar…