Across the world, the number of citizen science projects focusing on plastic pollution is increasing. These projects often last for multiple years, which makes retaining volunteers challenging.... Show moreAcross the world, the number of citizen science projects focusing on plastic pollution is increasing. These projects often last for multiple years, which makes retaining volunteers challenging. However, our knowledge is limited regarding the effect of long-term involvement on citizen scientists’ motivation, attitude, and knowledge, especially for plastic pollution projects. Therefore, this study measured citizen scientists’ motivation, attitude, and knowledge in the Dutch Clean Rivers project before and during monitoring plastic pollution on riverbanks between 2017 and 2021.In total, 403 Clean Rivers participants completed a pre-survey, and a portion of them participated in one or multiple post-surveys throughout the years of monitoring. They were especially driven by Project Action motivations and Environmental motivations like tackling the source of pollution and doing something about the plastic soup, rather than being motivated by an Interest in Scientific Research like the desire to learn about scientific research. Project Action motivations increased significantly, especially within the first year of participation. Participants’ attitudes towards nature and science were initially high and did not increase significantly. Furthermore, while participants’ knowledge of plastic pollution was already high at the start, their knowledge of scientific research was not, and both increased significantly, especially in the first year of participation. The findings of this longitudinal study can contribute to improving the recruitment and retention of volunteers in current and future citizen science projects. Show less
This thesis focuses on data found in the field of computational drug discovery. New insight can be obtained by applying machine learning in various ways and in a variety of domains. Two studies... Show moreThis thesis focuses on data found in the field of computational drug discovery. New insight can be obtained by applying machine learning in various ways and in a variety of domains. Two studies delved into the application of proteochemometrics (PCM), a machine learning technique that can be used to find relations in protein-ligand bioactivity data and then predict using a virtual screen whether compounds that had never been tested on a particular protein, or set of proteins. With this, sets of compounds were suggested for experimental validation that were significant in a myriad of ways. Another study investigated the mutational patterns in cancer, applying a large dataset of mutation data and identifying several motifs in G protein-coupled receptors. The thesis also contains the work done on the Papyrus dataset, a large scale bioactivity dataset that focuses on standardising data for computational drug discovery and providing an out-of-the-box set that can be used in a variety of settings. Show less
The sequence-dependence of biomolecular interactions involving nucleic acids and proteins is essential for numerous processes inside the cell. Insights into the underlying molecular mechanisms have... Show moreThe sequence-dependence of biomolecular interactions involving nucleic acids and proteins is essential for numerous processes inside the cell. Insights into the underlying molecular mechanisms have been obtained using various biochemical and biophysical methods on two different levels — bulk and single-molecule. These have complemented each other as single-molecule studies excel in observing multi-state dynamic interactions, but perform only at low throughput; while bulk studies can probe many different sequences simultaneously, but providing limited kinetic information. To unite the strengths of both levels, we developed high-throughput Single-molecule Parallel Analysis for Rapid eXploration of Sequence space (SPARXS), that allows the study of molecular structure, kinetics and interactions for thousands of different sequences simultaneously at the single-molecule level. We, for the first time, combine single-molecule fluorescence with next-generation Illumina sequencing. As a proof of principle we apply SPARXS to study the sequence-dependent kinetics of the four-way DNA Holliday junction, occurring among others during homologous recombination. Using SPARXS we observe the dynamic behavior of 120,000 Holliday junction molecules covering 3750 distinct core sequences, a result unattainable with previous techniques. Overall, the mechanistic insights obtained using SPARXS will give an entirely new view on the relationship between sequence, structure and function. Show less
A strong correlation exists between abdominal aortopathy and atherosclerosis. In thoracic aortopathy however, the prevalence of atherosclerosis and its role in the etiology of thoracic aortopathy... Show moreA strong correlation exists between abdominal aortopathy and atherosclerosis. In thoracic aortopathy however, the prevalence of atherosclerosis and its role in the etiology of thoracic aortopathy remained unknown. This thesis therefore studied the cardiovascular disease burden within this patient group. These results showed that the prevalence of atherosclerosis (i.e. cardiovascular disease burden), in contrast to abdominal aortopathy, is not increased within the thoracic aortopathy population. Show less
In between 1968 and 1973, the Dutch Atlantic was home to four Black Power organizations: the Black Panthers of Curaçao (1968-1970), Antillean Black Power (1969-1970), the Dutch Black Panther... Show moreIn between 1968 and 1973, the Dutch Atlantic was home to four Black Power organizations: the Black Panthers of Curaçao (1968-1970), Antillean Black Power (1969-1970), the Dutch Black Panther Solidarity Committee (1969-1970), and Black Power Suriname / Afro-Sranan (1970-1973). This dissertation asks why and how these organizations aligned with the transnational movement. Based on archival research conducted in Curaçao, Suriname, the United States, and the Netherlands, it argues that they did so because Black Power offered them an alternative path to decolonization. Instead of striving for equal participation in the Kingdom of the Netherlands, as colonial reformists did, or promoting self-reliance, as nationalists did, Black Power activists believed the best way to free themselves from the legacies and realities of colonialism was to join the movement's global network of Black solidarity, cooperation, and unity. Show less
Online behavioral advertising (OBA) is a form of advertising that relies on data about users’ behavior (e.g., clicks, likes, voice commands) and uses artificial intelligence (AI) to place ads that... Show moreOnline behavioral advertising (OBA) is a form of advertising that relies on data about users’ behavior (e.g., clicks, likes, voice commands) and uses artificial intelligence (AI) to place ads that users may be interested in. Ads that AI chooses to display often leave users in awe and concern them about the potential of total surveillance. People using these services have (legitimate) expectations that tech companies or democratic institutions protect their interests. Indeed, the European Union (EU) heavily regulates OBA, requiring, for example, that companies have users’ consent before their surveillance. Yet, these ads monetize most “free” online services and turn companies like Alphabet and Meta into the world’s wealthiest. Therefore, the industry is incentivized to acquire consumers’ consent by any means necessary, often through manipulation. As almost everyone has encountered manipulative “cookie banners” online, many have started to doubt if EU law can effectively protect consumers from the growing power of the tech industry. This thesis builds a framework of manipulation, describes consumer manipulation via OBA, constructs a theory of the harms of this phenomenon, and analyses its boundaries in the EU legal framework. The thesis concludes that the EU framework can effectively safeguard consumers, anticipating that the enforcement of the Digital Services Act (DSA) and the Digital Markets Act (DMA) will put an end to consumer manipulation (and exploitation) via OBA. Show less
This thesis explores North Korea’s influential role in the liberation of Southern Africa. Specifically, it examines the question of how political elites in Southern Africa benefitted from North... Show moreThis thesis explores North Korea’s influential role in the liberation of Southern Africa. Specifically, it examines the question of how political elites in Southern Africa benefitted from North Korean support, from 1960 until 2020. The main argument of this book is that liberation (and not the Cold War) is the leitmotif for African–North Korean relations, as the transition from anticolonial struggles to postcolonial politics is characterised by continuity not change. This approach is based on three assumptions. First, political culture in Southern Africa transcends national boundaries, which is a legacy of the exile dimension of the struggle for liberation. Second, scholarship must shift its lens from states to regimes. Third, the standard periodisation of African history and the Cold War distorts a proper understanding of African–North Korean interactions. Show less
Inaugural Lecture by Prof.dr. Florian A. Schneider on the acceptance of his position as professor Modern China at Leiden University on Monday 6 May 2024
Inaugural Lecture by Prof.dr. Nadine N.W. Akkerman on the acceptance of her position as professor of Early Modern Literature & Culture at Leiden University on Friday 3 May 2024