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When are leaders blamed for bad events that never happened? Partisanship and close counterfactual catastrophes
No full textHow much blame do leaders deserve for counterfactual catastrophes: disasters that could have occurred under their watch but never did? We propose that when people oppose (vs. support) a leader, they are more likely to answer this question by considering how close the catastrophe came to occurring. In two preregistered experiments (total N = 1927), U.S. participants assigned greater blame for counterfactual catastrophes (e.g., an imagined nuclear attack) to Presidents Trump and Biden when these catastrophes were framed as having been close to occurring rather than distant – but especially when judging the president they opposed (vs. supported). The results reveal a novel way in which counterfactual thinking facilitates partisan reasoning. Evaluating a leader they oppose may decrease people's focus on how a catastrophe never occurred and increase their focus on how it nearly occurred. We discuss how imagination can fuel political polarization
Bat-human encounters:Exploring practices of conservation, coexistence and care in urban spaces in the Netherlands
No full textThis thesis explores the dynamic relationships between humans and bats in urban environments in the Netherlands, highlighting how encounters, perceptions, and emotional experiences influence conservation outcomes. While urban wildlife conservation typically focuses on managing species at a broader level, this research emphasizes the emotional, ethical, and spatial aspects of human-bat interactions, areas that have largely been overlooked.The study involves three participant groups: bat advocates, residents, and students, and it utilizes multiple theoretical frameworks. Actor-Network Theory is employed to examine how the interactions among bats, humans, spaces, and technologies shape conservation practices. The Ethics of Care emphasizes empathy, responsibility, and attentiveness in shared living environments, while Compassionate Conservation considers coexistence within the context of design, legislation, and the agency of bats. Environmental Literacy underscores the importance of affective educational practices in promoting understanding and advocacy for urban bat conservation.Through a qualitative approach, the research reveals how emotions, knowledge, and spatial contexts interact to transform traditional conservation models. It demonstrates that bats actively participate in socio-ecological networks and that human-bat relationships are deeply rooted in place-based care and long-term engagement. The thesis advocates for recognizing bats as co-designers of urban spaces and partners in conservation efforts. By integrating human values, bat agency, and relational ethics, it envisions urban conservation as a collaborative, multispecies effort, promoting more inclusive and vibrant city spaces that support diverse forms of life
Precision modelling of the radio sky for 21-cm cosmology with LOFAR
No full textUnderstanding how the first stars and galaxies formed is one of the central goals of modern cosmology. A unique way to probe this early phase of the Universe is through the 21-cm spectral line emitted by neutral hydrogen during the Epoch of Reionization. Detecting this signal, however, is extremely challenging: it is buried beneath much brighter radio emission from our Galaxy and from distant extragalactic sources, and its extraction requires both sensitive instruments and careful data analysis. This thesis focuses on improving our ability to isolate the cosmological signal using observations from the Low Frequency Array (LOFAR). A central challenge lies in accurately modelling and removing bright radio sources, whose imperfect subtraction can obscure the faint 21-cm signal. Particular attention is given to the development of advanced methods that provide more accurate spectral and spatial source models. Using these techniques, this work demonstrates significant progress in reducing foreground contamination and improving the quality of the recovered cosmological signal. These improvements are achieved through detailed modelling of both bright sources within the field of view, such as 3C61.1 and 3C196, and bright off-axis sources, such as Cygnus A. In addition, this thesis presents the first results obtained from the 3C196 field, which represents a promising alternative to the traditionally studied North Celestial Pole field. Together, these results show that accurate sky modelling across different observational scenarios is a key step toward a robust detection of the faint cosmological signal from the early Universe
Development of the first prediction model for radiation-induced contrast enhancement after proton therapy for posterior fossa tumours in paediatric patients
No full textBackground/purpose: Radiation-induced contrast enhancement (RICE) has been identified as a metric of subclinical toxicity. The aim of this study was to develop a normal tissue complication probability (NTCP) model for RICE after proton therapy in paediatric patients with posterior fossa tumours. Materials and methods: Paediatric patients (n = 75) treated with proton radiotherapy (49.6–59.4 Gy (RBE)), focally or in combination with craniospinal axis irradiation, were included. Follow-up magnetic resonance imaging scans were evaluated for RICE. Dose (D), dose multiplied by dose-averaged linear energy transfer (D⋅LETd), organ at risk association, RICE association and age data were extracted to construct a multivariable logistic regression model to predict RICE in voxels. NTCP was calculated using univariable logistic regression with RICE status as the dependent variable and the expected number of RICE voxels as the independent variable. Results: A total of 60 RICE lesions were identified in 23 patients (30.7 %), of which 36 (60 %) were located in the brainstem, primarily the pons. We observed an increased density of RICE voxels in regions with a combination of high D (38.32–55.94 Gy) and medium-to-high LETd (1.89–6.00 keV/µm) values. In addition, younger age and the anatomical location in the pons were identified as independent risk factors for RICE. The NTCP model's optimism corrected area under the receiver operating characteristic curve (AUC) was 0.79, and the Brier score was 0.16. Conclusion: We developed models to predict RICE in paediatric patients. The RICE probability at the voxel- and patient-level increased with D and D⋅LETd, younger age and within the brainstem pons.</p
Characterizing mobility lifestyles in Finnish cities
No full textCar-centric urban development and car-dependent mobility practices are causing increasing harm to society and the environment. Achieving transformative changes in urban mobility requires a deeper understanding of citizens’ mobility lifestyles. This study investigates mobility lifestyles in three Finnish cities using public participation geographic information system (PPGIS) survey data from 3,260 participants. Cluster analysis identified six distinct lifestyle profiles based on travel attitudes and neighbourhood preferences. These profiles differ in travel behaviour, sociodemographic characteristics, residential locations, and perceived health and well-being.We identified three car-oriented and three sustainable mobility lifestyle profiles, indicating the coexistence of contrasting orientations within urban populations. Sustainable mobility lifestyles were more commonly associated with car-free attitudes, multimodal travel behaviour, younger age groups, lower income, and women. Attitudes towards active mobility, car use, and car ownership varied and were predictors of travel behaviour across profiles. However, mismatches between travel attitudes and behaviour were also observed, indicating that mobility choices may be caused by contextual factors. Neighbourhood preferences aligned partially with both sustainable and car-oriented profiles, suggesting nuanced associations with mobility behaviour.The findings advance understanding of the diverse motivations and conditions shaping everyday mobility practices. By revealing group-specific barriers and opportunities for behavioural change, the study provides actionable insights to support targeted interventions and sustainability transitions in urban mobility
Nanoparticle-Mediated Delivery of Adenosine 5′-Monophosphate Enhances 5-Oxoprolinase Activity to Mitigate Oxidative Stress in Heart Failure
No full textABSTRACT Oxidative stress, a key driver of heart failure progression, is exacerbated by 5-oxoproline accumulation due to reduced 5-oxoprolinase (OPLAH) activity. While enhancing OPLAH function represents a promising therapeutic strategy, effective intracellular delivery of activity-modulating compounds remains highly challenging. Here, we develop a comprehensive approach combining high-throughput screening technology and advanced nanocarrier design to address effective intracellular delivery. Through the screening of an FDA-approved compound library, we identify adenosine 5′-monophosphate (AMP) as a novel OPLAH activator, demonstrating direct modulation through thermal shift assay and a dose-dependent activation via liquid chromatography mass spectrometry (LC-MS/MS) analysis. To overcome the AMP's limited cellular permeability, we engineer acetalated dextran spermine-modified nanoparticles (AcDXSp-NPs) with optimized physicochemical properties for efficient intracellular delivery. The AMP-loaded nanoparticles exhibit a high encapsulation efficiency (>70 and controlled pH-dependent release. In cell-based studies, these nanocarriers significantly enhance OPLAH activity, evidenced by a >503C5-glutamate production from the isotope-labeled 13C5-5-oxoproline. This integrated approach, combining enzyme activation with advanced delivery systems, may present a promising therapeutic strategy for oxidative stress-related conditions, particularly conditions like heart failure; it also demonstrates the potential of materials-based solutions for challenging therapeutic targets
Alterations in lipid, redox, and energy metabolism in recent onset psychosis:a metabolomics study in non-smoking individuals and matched controls
No full textPsychotic disorders are associated with systemic metabolic alterations, but these associations may be confounded by smoking. We investigated plasma metabolites in 47 non-smoking recent onset psychosis patients and 36 matched (on age, sex and ethnicity) healthy controls using untargeted LC MS metabolomics. We applied univariate, multivariate and pathway analyses, with subgroup exploration in patients that were diagnosed with schizophrenia spectrum disorder (SSD) specifically. We identified 28 significantly altered metabolites predominantly reflecting lipid metabolism (elevated saturated free fatty acids, glycerol 3 phosphate, conjugated bile acid), redox imbalances (decreased L cysteine, L cystine and taurine) and energy metabolism (reduced pyruvate). These alterations remained significant after adjusting for sex, antipsychotic treatment and metabolic syndrome parameters. Enrichment analyses highlighted taurine/hypotaurine metabolism, alanine/aspartate/glutamate pathways and fatty acid biosynthesis in psychosis. Within the SSD subgroup (n = 28), metabolic perturbations were more pronounced, showing stronger depletion of reducing equivalents and elevated free fatty acids. These findings indicate a specific systemic metabolic signature in psychosis independent of smoking, sex, antipsychotic medication or metabolic syndrome. The pattern suggests mitochondrial dysfunction and increased oxidative stress, accompanied by compensatory lipid mobilization. These findings identify redox and energy metabolism as promising targets for future pharmacological or metabolic interventions in SSD.</p