Leiden University Scholary Publications
Not a member yet
131438 research outputs found
Sort by
Impacts of a nano-enabled pesticide formulation (nTiO2-coated carbendazim) and its constituents on the freshwater snail Lymnaea stagnalis & damselfly Ischnura elegans assessed via in-situ bioassays
Get PDFNovel pesticidal products in which active substances are delivered via nanoscale carrier systems have been suggested to offer functional and environmental benefits over conventional pesticide formulations. Nevertheless, non-target impacts associated with such nano-enabled pesticides remain largely unexplored. The current study compares effects from a nano-TiO2-coated formulation of carbendazim (i.e., nTiO2-coated carbendazim) with those of its active substance (i.e., the fungicide carbendazim), coating material (i.e., nanoscale TiO2), and a treatment in which the latter two are combined, by means of in-situ bioassays. Bioassays focused on the freshwater snail Lymnaea stagnalis and larvae of the damselfly Ischnura elegans, two invertebrate species representing different niches. For L. stagnalis, effects on survival, growth, and feeding were assessed over 29 days, and resource utilization rates of microbial communities present on its provided food source were analyzed to determine feeding-related indirect effects. For I. elegans, survival, feeding, emergence (i.e., development into imagines), and body size upon emergence were assessed over 57 days. Mortality rates of L. stagnalis increased by ∼40 % in nTiO2 and ∼50 % in combined (i.e., carbendazim & nTiO2) treatments applied at environmentally realistic concentrations, but insignificantly in nTiO2-coated carbendazim treatments. We argue that differences in this regard are likely to have arisen from contrasting photocatalytic activity of the nTiO2 utilized in respective treatments. Microbial community carbon utilization profiles exhibited minimal differences between treatments. I. elegans survival, feeding and growth rates were unaffected, but a slight decrease in emergence time was observed across treatments. The findings of the current study highlight that photocatalytic properties of nanomaterials can be an important factor for consideration regarding non-target impacts of nano-enabled products with agricultural applications.Environmental Biolog
Alexander von Humboldt on race: beyond the Kantian frame
Get PDFThis article concerns the question of race in late Enlightenment German philosophy and makes the case for why we in that context should reconsider the writings of Alexander von Humboldt in the philosophical canon. Contrary to many other authors who wrote on both natural history and politics in the late Enlightenment, Humboldt produced both a scientific and a political critique of then-contemporaneous natural historical conceptions of race. I give an account of these by analysing his reflections on the concepts of race and species in the first volume of the popular scientific work Cosmos (1845). I also show how Humboldt combined a critique of the pseudo-scientific concepts of race that sustain biological racialism with a diagnostic of the juridical and political reality of racial divides that came to be instituted by the colonial systems of governance and slave-labour in plantation economies. This latter aspect is found in the demographic discussions in his so-called political essays on the Kingdom of New Spain and Cuba (1808–10, 1825–26). The dual perspective onto race theory on the one hand and practices of racialisation on the other makes Humboldt a particularly interesting case to consider in a moment where critical histories of philosophy are re-examining both effects of racialisation and conceptions of race in the history of philosophy. I argue that attending to authors like Humboldt offers one fruitful way to counter two distinct problems that arise from what I call the ‘Kantian frame’ within discussions of Enlightenment race theory and racism: on the one hand that of an overly individualist conception of racism and on the other that of the absence within Kant’s own corpus of expressed links between the theory of race and the practices of racial domination.Political Philosophy and Ethic
Ecological function of phenazine in soil
No full textPhenazines, antimicrobial secondary metabolites, inhibit Gram-positive bacteria by targeting topoisomerase IV, but Bacillus cohabiting with phenazine-producing Pseudomonas can evolve resistance, enabling synergism for agricultural biocontrol.Microbial Biotechnolog
From prescription to bleeding complication: challenges surrounding daily anticoagulant care
Get PDFThis thesis explores key challenges in daily clinical anticoagulant care: inappropriate prescribing, suboptimal adherence, and bleeding complications.The prevalence, underlying rationales, predictors, and potential clinical consequences of inappropriate inpatient prescribing of direct oral anticoagulants (DOACs) were examined. Dose reduction criteria from various guidelines were reviewed, illustrating the complexity of achieving appropriate dosing in practice.Adherence is critical to treatment success. We assessed adherence to oral anticoagulation in patients with atrial fibrillation (AF), identified predictors for non-adherence, and examined patients’ beliefs about anticoagulants and their experiences with side effects. Both pharmacy-based and self-reported adherence measures were evaluated to capture different dimensions of treatment behaviour.Bleeding remains the principal limitation of anticoagulant therapy. We investigated the use, effectiveness, and safety of idarucizumab, a reversal agent for dabigatran. Moreover, the predictive performance of bleeding risk scores was evaluated in patients with AF and in the high-risk population of left ventricular assist device (LVAD) recipients.Together, these studies provide an integrated overview of the multifaceted challenges in anticoagulant management, offering insights into prescribing practices, patient engagement, and bleeding risk assessment in routine care.Abbott; Bayer B.V.; ChipSoft; Daiichi Sankyo Nederland B.V.; Federatie van Nederlandse Trombosediensten; Stago BNL; Trombosestichting Nederland; VarmX; ViatrisLUMC / Geneeskund
Reunifying children in out-of-home care: does NSW’s permanency support program affect restorations?
Get PDFHervorming Sociale Regelgevin
De nationalistische internationale: sleuteljaar 1979
Get PDFOm het succes van radicaal-rechts populisme te verklaren, moeten we terug naar eind jaren zeventig, toen twee wereldwijde stromingen opkwamen: neoliberalisme en identiteitspolitiek.Politics, Culture and National Identities 1789-presen
What kind of opposition do citizens want?
Get PDF Opposition parties play a crucial role in democracies. While scholars have extensively studied opposition behaviour and institutional powers, little is known about what citizens expect from opposition parties and how they evaluate these expectations being met. This study addresses this gap by examining citizens’ views on three key opposition roles - oversight, cooperation, and offering alternatives - and their perceived fulfilment across four countries: Canada, Denmark, the Netherlands, and the United Kingdom. Based on a citizen survey, this study assesses how individual characteristics (democratic satisfaction, political interest, education) and institutional context are related to these views. Citizens across all four countries value cooperation. Preferences for the ‘alternative’ role vary between institutional settings. On the individual level, conflict-oriented and dissatisfied citizens value cooperation less, while those with higher education and political interest find oversight and cooperation more important. NWOVI.Vidi.195.020Institutions, Decisions and Collective Behaviou
Advancing the LeiCNS-PK3.0 model for prediction of CNS pharmacokinetics: nonlinear BBB transport, inter-species scaling, and machine learning
Get PDFThis thesis focuses on enhancing predictions of central nervous system drug exposure using the LeiCNS-PK3.0, a physiologically based pharmacokinetic model. The research expands the model's capability to simulate central nervous system drug distribution, with a particular focus on morphine and its metabolites. Key findings include the impact of nonlinear blood-brain barrier transport, μ-opioid receptor binding kinetics, and P-glycoprotein-mediated drug-drug interactions on morphine exposure and effects in the brain. The model was also extended to mouse physiology, improving its translational potential. A machine learning model was developed to predict the blood-brain barrier partition coefficient, reducing the need for animal testing.The integration of these methods enables more accurate central nervous system pharmacokinetic predictions and informs better dosing strategies. The thesis highlights the potential of central nervous system physiologically based pharmacokinetic model models to improve drug development, support personalized medicine, and minimize reliance on animal experiments. Future directions include incorporating disease-specific data, genetic variability, and developing a user-friendly interface to promote clinical and regulatory use. The overall framework holds promise for optimizing central nervous system drug therapies and facilitating drug repurposing.Pharmacolog
TGF-β and extracellular vesicles in the tumor microenvironment
Get PDFThis PhD thesis explores the intricate role of the tumor microenvironment (TME), focusing on how cellular interactions and extracellular vesicles (EVs) contribute to cancer progression. It highlights cancer-associated fibroblasts (CAFs) as key modulators of the TME, emphasizing their heterogeneity, plasticity, and ability to promote tumor growth, immune evasion, and resistance to therapy. A central focus is the dual role of Transforming Growth Factor Beta (TGF-ß), which not only activates CAFs but also influences EV secretion and function. The thesis demonstrates that TGF-ß reduces EV release in breast cancer cells by downregulating RAB27A/B, alters EV cargo, and reprograms EV-mediated communication. Furthermore, it shows that EVs from TGF-ß-activated CAFs induce further CAF activation and suppress CD8+ T cell activity, largely through surface-bound proteins that enhance TGF-ß signaling in recipient cells. These findings reveal a feedback loop in which TGF-ß shapes the TME through EV-mediated intercellular signaling, offering insights into potential therapeutic targets.This research was supported by Oncode Institute base funds and China Scholarship CouncilLUMC / Geneeskund
