Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy which shows unparalleled therapeutic resistance due to its genetic and cellular heterogeneity, dense stromal tissue, and... Show morePancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy which shows unparalleled therapeutic resistance due to its genetic and cellular heterogeneity, dense stromal tissue, and immune-suppressive tumour microenvironment. Oncolytic virotherapy has emerged as a new treatment modality which uses tumour-specific viruses to eliminate cancerous cells. Non-human primate adenoviruses of the human adenovirus B (HAdV-B) species have demonstrated considerable lytic potential in human cancer cells as well as limited preexisting neutralizing immunity in humans. Previously, we have generated a new oncolytic derivative of the gorilla-derived HAdV-B AdV-lumc007 named ‘GoraVir’. Here, we show that GoraVir displays oncolytic efficacy in pancreatic cancer cells and pancreatic-cancer-associated fibroblasts. Moreover, it retains its lytic potential in monoculture and co-culture spheroids. In addition, we established the ubiquitously expressed complement receptor CD46 as the main entry receptor for GoraVir. Finally, a single intratumoural dose of GoraVir was shown to delay tumour growth in a BxPC-3 xenograft model at 10 days post-treatment. Collectively, these data demonstrate that the new gorilla-derived oncolytic adenovirus is a potent oncolytic vector candidate that targets both pancreatic cancer cells and tumour-adjacent stroma. Show less
Dental calculus. This small, hard, inconspicuous substance that forms on the teeth of humans and animals contains a surprising amount of information about our lives. During its formation and growth... Show moreDental calculus. This small, hard, inconspicuous substance that forms on the teeth of humans and animals contains a surprising amount of information about our lives. During its formation and growth as a living biofilm, it accumulates a wide variety particles, especially bacteria and food debris.What makes this so interesting to archaeologists is that, when plaque hardens and forms dental calculus, these particles become trapped and well-protected against removal and degradation during hundreds to thousands of years, preserving a picture of past activities.The major problem—one of the major problems, for there are several—one of the many major problems is that this picture was never a complete picture of a lifetime of activities, and that picture fades over time. We know that these problems exist and that they limit our interpretations of past activities. What we need to do is approach these problems at a fundamental level. In my dissertation I introduce a protocol for growing artificial dental calculus. Working with a very controlled model allows me to explore the influence of a wide range of factors that may affect the uptake of particles into dental calculus, and better explain why and how our picture is incomplete. Show less
Tuberculosis (TB) is associated with 1.5 million deaths annually. There is a need exists to optimize both current as well as novel antibiotic combination treatment strategies to improve the... Show moreTuberculosis (TB) is associated with 1.5 million deaths annually. There is a need exists to optimize both current as well as novel antibiotic combination treatment strategies to improve the effectiveness and safety of treatments against TB. This PhD thesis has described how various quantitative pharmacology modeling approaches can contribute to the further development and optimization of both existing and novel therapies and treatment strategies against TB. Show less
Householder, J.E.; Wittmann, F.; Schöngart, J.; Piedade, M.T.F.; Junk, W.J.; Latrubesse, E.M.; ... ; Steege, H. ter 2024
Amazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and... Show moreAmazonia's floodplain system is the largest and most biodiverse on Earth. Although forests are crucial to the ecological integrity of floodplains, our understanding of their species composition and how this may differ from surrounding forest types is still far too limited, particularly as changing inundation regimes begin to reshape floodplain tree communities and the critical ecosystem functions they underpin. Here we address this gap by taking a spatially explicit look at Amazonia-wide patterns of tree-species turnover and ecological specialization of the region's floodplain forests. We show that the majority of Amazonian tree species can inhabit floodplains, and about a sixth of Amazonian tree diversity is ecologically specialized on floodplains. The degree of specialization in floodplain communities is driven by regional flood patterns, with the most compositionally differentiated floodplain forests located centrally within the fluvial network and contingent on the most extraordinary flood magnitudes regionally. Our results provide a spatially explicit view of ecological specialization of floodplain forest communities and expose the need for whole-basin hydrological integrity to protect the Amazon's tree diversity and its function. Show less
Zhang, L.; Cao, Z.; Sivertsen, G.; Kochetkov, D. 2024
Drawing on new data, Lin Zhang, Zhe Cao, Gunnar Sivertsen, and Dmitry Kochetkov explore how the conflict in Ukraine has changed Russian science and how international sanctions have played a minor... Show moreDrawing on new data, Lin Zhang, Zhe Cao, Gunnar Sivertsen, and Dmitry Kochetkov explore how the conflict in Ukraine has changed Russian science and how international sanctions have played a minor role compared to domestic politics in isolating Russian scientists. Show less
Cerebral Amyloid Angiopathy (CAA) is one of the main causes of intracerebral hemorrhage (ICH) in the elderly, and affects millions of people worldwide. CAA is caused by the deposition of the... Show moreCerebral Amyloid Angiopathy (CAA) is one of the main causes of intracerebral hemorrhage (ICH) in the elderly, and affects millions of people worldwide. CAA is caused by the deposition of the protein Amyloid-β in the walls of the cerebral and leptomeningeal vessels, which leads to vessel fragility and eventually rupture. CAA has a variable disease course and can present with a spectrum of symptoms. There is currently no cure for CAA, and certain diagnosis during life remains challenging.This thesis has used data from patients with hereditary and non-hereditary (sporadic) CAA to investigate novel clinical and radiological (MRI) markers of CAA, and has used them to formulate a pathophysiologic framework for the temporal ordering of disease processes in CAA. Our results provide new insights in the disease cascade, can aid in diagnosing the disease and have important implications for future clinical trial design, aiding in the identification and timing of candidates for disease-modifying treatments and the choice for the appropriate biomarkers to monitor treatment effect. CAA is a disease with a complex disease cascade and a large variety in disease course, both clinically and radiologically. However, it is just this variety that gives hope for the future: if we find what drives variability in CAA we might find ways for disease modification, prevention and treatment, and identification of in vivo biomarkers with specificity for CAA are a vital part of this search. Show less
Lung cancer is the leading cause of cancer death in the Netherlands. For years chemotherapy was the only (palliative) treatment, with a short survival of only months. Since the introduction of... Show moreLung cancer is the leading cause of cancer death in the Netherlands. For years chemotherapy was the only (palliative) treatment, with a short survival of only months. Since the introduction of immunotherapy in 2015, this survival has increased significantly, with the first results showing a survival of even a few years. However, the response rate is relatively low, the treatment is expensive and the (low percentage of) side effects are severe. Therefore a biomarker is needed to predict which patients would benefit of immunotherapy.This thesis is about the search for a new biomarker. With the use of the RNA of platelets, proteins, tumor markers in blood and a an electronic nose for exhaled breath, we tried to find a non-invasive biomarker for the prediction of response on immunotherapy and for the (future) use in clinical practice, some of which are promising. Show less
Space data provide timely and reliable information that enables a wide variety of civil and commercial applications. Thanks to their volume, velocity, variety, and veracity, space big data create... Show moreSpace data provide timely and reliable information that enables a wide variety of civil and commercial applications. Thanks to their volume, velocity, variety, and veracity, space big data create the potential for additional benefits from space data.The benefits of space big data depend on the ways in which data are collected, accessed, used, and disseminated, therefore the laws and data policies that affect them should be studied. This thesis answers the question ‘How could space big data be regulated to address existing legal challenges and enhance their benefits?’. In particular, it identifies the laws and data policies that are relevant to the collection, access, use, and dissemination of space big data, among the legal frameworks that govern activities involving space or data. It also assesses the impact of the relevant laws and data policies, in terms of the limitations they impose on data collection, access, use, and dissemination. From the analysis of the relevant laws and data policies and their impact, the thesis draws the areas where their application encounters difficulties and describes the respective legal challenges. Based on these findings, recommendations are provided for overcoming the legal challenges and enhancing the collection, access, use, and dissemination of data, and by extension, their benefits. Show less
In this dissertation, Dutch secondary school teachers’ attitudes, knowledge, noticing skills and reasoned practices regarding culturally responsive teaching in a multicultural classroom context,... Show moreIn this dissertation, Dutch secondary school teachers’ attitudes, knowledge, noticing skills and reasoned practices regarding culturally responsive teaching in a multicultural classroom context, were examined. These components of culturally responsive teaching were addressed in three explorative, qualitative studies. In the first study, expert teachers’ reasoned practices were examined by in depth interviews. In the second and third study, spherical video-based virtual reality (SV-VR) clips of a multicultural classroom were used to provide teachers an immersive, authentic and comparable experience. The second study focussed on student teachers’ and expert teachers’ noticing through a cultural lens. In the third study, the SV-VR clips were used for deeper reflections in focus groups through which expert teachers’ culturally responsive attitudes, knowledge, noticing skills and reasoned practices were examined. The main results of this dissertation show that expert teachers teaching at Dutch multicultural schools indicate that working on a good interpersonal relationship with students is crucial. Moreover, the importance of adopting a genuinely curious attitude regarding students’ Funds of Knowledge/ Identity is often referred to. Such knowledge is also seen as necessary to notice relevant classroom events. Recommendations are made for teacher education regarding preparing teachers to teach multicultural classes. Show less
In this dissertation, I draw on twelve months of ethnographic fieldwork with Egyptians in Amsterdam to study how the nationalization of our imagination and social-legal and material infrastructures... Show moreIn this dissertation, I draw on twelve months of ethnographic fieldwork with Egyptians in Amsterdam to study how the nationalization of our imagination and social-legal and material infrastructures mediates social life. I describe how, just like the group of people categorized as Egyptian in Amsterdam is diverse, the Dutch state is too, consisting of a a range of images, laws, organizations, and people that embody them. I argue that this Dutch state multiple structures almost all aspects of life, but ultimately cannot define who we are, or what we do. Show less
The decision for immediate breast reconstruction after mastectomy is a preference-sensitive decision. For preference-sensitive decisions, shared decision making is propagated, but not yet properly... Show moreThe decision for immediate breast reconstruction after mastectomy is a preference-sensitive decision. For preference-sensitive decisions, shared decision making is propagated, but not yet properly implemented. Furthermore, prior studies identified unmet decision support needs in women considering breast reconstruction. With this thesis we aimed to optimally support women in making an informed decision about breast reconstruction. For this purpose, we developed an online patient decision aid (pDA) for breast cancer patients considering immediate breast reconstruction after mastectomy. This thesis describes the development and evaluation of this pDA. In our multicenter randomized controlled trial including 250 participants, we found that women who used the pDA felt better prepared for decision making, than women who received usual care. Other outcomes did not differ between both groups. Show less
The parabolic Anderson model (PAM), which is the Cauchy problem for the heat equation with random potential. The PAM is a mathematical model that describes how mass (i.e. matter or energy) flows in... Show moreThe parabolic Anderson model (PAM), which is the Cauchy problem for the heat equation with random potential. The PAM is a mathematical model that describes how mass (i.e. matter or energy) flows in a medium in the presence of a field of sources and sinks.The PAM has been extensively studied on regular lattices and is well understood there. However, the lattice is not always a suitable model and we look for extensions to random graphs. Very little is known for general graphs and the literature is extremely sparse. The present thesis is a contribution to this developing area. Because sparse random graphs can often be approximated by trees, the natural first step is to consider the PAM on a tree. In particular, this thesis is devoted to studying the PAM on random trees. Show less
Time-series forecasting through modelling sequences of temporally dependent observations has many industrial and scientific applications. While machine learning models have been widely used to... Show moreTime-series forecasting through modelling sequences of temporally dependent observations has many industrial and scientific applications. While machine learning models have been widely used to create time-series forecasting models, creating efficient and performant time-series forecasting models is a complex task for domain users. Automated Machine Learning (AutoML) is a growing field that aims to make the process of creating machine-learning models accessible for non-machine learning experts. This is achieved by optimising machine learning pipelines automatically. Time-series machine-learning pipelines include various specialised pre-processing steps that are not currently supported by existing AutoML systems. This dissertation investigates how AutoML can be extended to time-series data analysis problems such as time-series forecasting. Several challenges arise when developing specialised AutoML systems for time-series forecasting. For instance, advanced machine-learning pipelines that can extract time-series features and select well-suited machine-learning models need to be developed. Also, extra hyperparameters such as the window size, which shows how many historical data points are helpful, need to be optimised by the AutoML system. This dissertation addresses these issues. We provide a comprehensive overview of the AutoML research field, including hyperparameter optimisation techniques, neural architecture search, and existing AutoML systems. Next, we investigate the use of AutoML for short-term forecasting, single-step ahead time-series forecasting, and multi-step time-series forecasting with time-series features. Show less
This thesis contains several investigations into the contribution of complement proteins, especially C1q, in several human diseases. Additionally, human autoantibodies against C1q (anti-C1q) are... Show moreThis thesis contains several investigations into the contribution of complement proteins, especially C1q, in several human diseases. Additionally, human autoantibodies against C1q (anti-C1q) are studied, cloned and characterized in order to further the understanding of their role in autoimmune disease. Show less
This thesis is about the role of elites in Ethiopia's nation-building process, 1960-2020. The study aims to answer questions regarding the formation, manoeuvering and circulation of elites. Using a... Show moreThis thesis is about the role of elites in Ethiopia's nation-building process, 1960-2020. The study aims to answer questions regarding the formation, manoeuvering and circulation of elites. Using a combination of theoretical notions on elite circulation and elite bargaining as conceptual framework, the research employed mixed methods, including in-depth interviews and document analysis. The trajectory of Ethiopian state formation is analyzed, highlighting elites' evolving nature and characteristics across different regimes. From the imperial regime via the Derg and EPRDF regimes to today’s PP rule, changes in power structures, ideologies, and socioeconomic dynamics have influenced elite composition and behaviour. Various dimensions and instruments of nation-building like economic integration, cultural integration, political centralization, and the establishment of effective state institutions are discussed. It is concluded that successive governments struggled to effectively utilize these instruments. It resulted in fragmentation, polarization, and authoritarianism, as key challenges were not met, including the failure to establish a compelling ideology and unifying national symbols, to provide overall public goods, to further civil society, or develop overarching language and education policies. The study proposes recommendations to address these challenges to nation-building, including elite reconfiguration, fostering consensus among ruling elites and stakeholders, and reducing the dominance of politicized ethno-elites. Show less
Why do people punish experienced unfairness if it induces costs for both the punisher and punished person(s) without any direct material benefits for the punisher? Economic theories of fairness... Show moreWhy do people punish experienced unfairness if it induces costs for both the punisher and punished person(s) without any direct material benefits for the punisher? Economic theories of fairness propose that punishers experience disutility from disadvantageous inequality and punish in order to establish equality in outcomes. We tested these theories in a modified Ultimatum Game (N = 1370) by examining whether people avoid the urge to reject unfair offers, and thereby punish the proposer, by deliberately blinding themselves to unfairness. We found that 53% of participants deliberately ignored whether they had received an unfair offer. Among these participants, only 6% of offers were rejected. As expected, participants who actively sought information rejected significantly more unfair offers (39%). Averaging these rejection rates to 21%, no significant difference to the rejection rate by participants who were directly informed about unfairness was found, contrary to our hypothesis. We interpret these findings as evidence for sorting behavior: People who punish experienced unfairness seek information about it, while those who do not punish deliberately ignore it. Show less
Nicotinamide adenine dinucleotide (NAD+) is the substrate used for the introduction of the ubiquitous and highly dynamic PTM in which either one or multiple adenosine diphosphate ribose (ADPr)... Show moreNicotinamide adenine dinucleotide (NAD+) is the substrate used for the introduction of the ubiquitous and highly dynamic PTM in which either one or multiple adenosine diphosphate ribose (ADPr) moieties are covalently attached to a nucleophilic side chain of an specific amino acid in the target protein to regulate cellular pathways including adipogenesis, DNA damage repair and gene expression. A significant fraction of the nucleophilic amino acid functionalities, most recently histidine and tyrosine, have been identified as ADPr-acceptor sites. In this thesis, new methodologies have been developed to synthesize peptide fragments carrying an ADPr modification to investigate ADP-ribosylation on histidine. Show less
