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Stepping Up to the Challenge: How European Parties Respond to Electoral Threats from a Growing Radical Right
No full textThe populist radical right has been rapidly rising in many European countries over the last decades. This rise has weakened the position of mainstream parties and introduced immigration as a salient issue in politics. Mainstream parties are required to find ways to deal with this new challenge. This thesis combines three papers that study the reactions of mainstream parties to this new challenge from three different angles. The first paper uses data from voter surveys to measure the threat the radical right poses to the voter base of various mainstream parties in eight European countries. Using this data, I show that parties who are at a higher risk of losing voters to the radical right take more restrictive positions on immigration in future elections. This effect persists even when controlling for radical right vote share, showing that parties are affected differently by the rise of the radical right and adjust their immigration policies according to the threat posed by the radical right. This previously ignored difference in threat helps explaining why parties accommodate the radical right, even though doing so is not correlated with a decrease in radical right vote share. The second paper examines competition between niche parties. A significant part of the radical right electorate comes from voters who are dissatisfied with democracy, and have traditionally voted for left-wing parties. This has prompted discussion about the possibility of a left-wing populist party that opposes immigration, but supports extensive welfare, challenging the radical right. The recent foundation of such a party in Germany, the Bündnis Sahra Wagenknecht, offers an opportunity to study the effects of a left-populist challenger on the party system in a case study. Analysing press releases from the German parties during the 2024 European Parliament election, I show that such a party can indeed compete for the radical right electorate, and prompts accommodation from the radical right. The AfD has responded to the rise of Bündnis Sahra Wagenknecht by emphasising its commitment to peace and its opposition to German involvement in Ukraine, as well as blurring its position on economics. Unlike other parties, most notably the mainstream right, it has not increased its emphasis on immigration. This shows that radical right parties are also responsive to their electorate, and can be challenged by other niche parties. Finally, the third paper highlights negative campaigning against radical right parties. Mainstream parties are generally thought of as more trustworthy and competent than challenger parties. They can use this advantage to compete against the radical right without requiring to talk about immigration, which is likely to alienate a part of their voters and draw more attention to the radical right. Despite these incentives to campaign negatively against radical right parties, there is very little work done on negative campaigning against radical right parties. In this paper, I use data from newspapers in five European democracies to show that on average, radical right parties face significantly higher levels of negative campaigning than mainstream parties of similar size and importance. This effect is primarily driven by attacks on their general valence. Radical right challenger parties face on average 150% more attacks on their general valence than other parties, all else being equal. The lack of research on this topic suggests that this is a major oversight in the literature on the radical right that requires deeper analysis. As a whole, my thesis offers a comprehensive view of the strategic party reactions to competition from radical right challengers, and how mainstream parties can meet this challenge
Additive Manufacturing via Rotational-Axis Fused Filament Fabrication of Poly L-Lactic Acid–Based Bioabsorbable Stent: Morphology, Mechanical, Degradation and Biocompatibility Properties
No full textBioabsorbable stents offer a significant advantage over metallic stents by providing temporary mechanical support to blood vessels and gradually degrading, thereby reducing the risk of long-term complications and restenosis. Polymeric stents, particularly those made from poly(l-lactic acid), have attracted attention for below-the-knee artery interventions because of their biocompatibility and potential for customized geometries and mechanical properties. However, challenges remain in the development of efficient and scalable fabrication techniques for such devices. This study aimed to develop and evaluate a rotational-axis fused filament fabrication method for the fabrication of bioabsorbable polymeric stents with improved mechanical and biological performance. A rotating-mandrel-based multiaxis system was used to print stents with a conventional closed-cell design while exploring variations in seam line overlaps and ring joint formations. Box-Behnken method was employed to systematically study the influence of key printing parameters─extrusion temperature, printing speed, and extrusion flow rate─on critical stent performance metrics: strut width, radial force, and flexural force. Microscopic analysis, radial compression, and three-point bending tests were performed for performance evaluation. Regression models and analysis of variance (ANOVA) revealed that the extrusion temperature and flow rate significantly influenced the mechanical properties. A multiobjective optimization approach was used to minimize the strut width while maximizing the radial and flexural strengths, resulting in a strut width of 205 μm and radial and flexural forces of 2.5 and 0.19 N, respectively, with an extrusion temperature, speed, and value of 200 °C, 90 mm/min, and 120%, respectively. Further characterization using microtomography and surface profilometry confirmed the structural integrity, consistent strut morphology, and surface quality. Accelerated degradation tests and in vitro biocompatibility assessments demonstrated favorable degradation profiles and cytotoxicity. A 95% mass change was observed in the printed stent after 10 d of accelerated degradation. This study presents a robust rotational-axis FFF method for scalable, bioabsorbable, and patient-specific stent fabrication.National Children’s Research Centre, IrelandCheck citation details on check dat
Solving the problem of simultaneous diagonalization of complex symmetric matrices via congruence
No full textWe provide a solution to the problem of simultaneous diagonalization via congruence of a given set of m complex symmetric n \times n matrices \{ A1, . . . ,Am\} , by showing that it can be reduced to a possibly lower-dimensional problem where the question is rephrased in terms of the classical problem of simultaneous diagonalization via similarity of a new related set of matrices. We provide a procedure to determine in a finite number of steps whether or not a set of matrices is simultaneously diagonalizable by congruence. This solves a long-standing problem in the complex case
Combined Numerical and Experimental Investigation of Solid Microneedle-Skin Interaction and Penetration
No full textMicroneedle patches have long been proposed as an effective platform for wearable diagnostics and enhanced transdermal drug delivery. However, microneedle patches suffer from inconsistent skin penetration and subsequent unreliable retention and therapeutic delivery, a severe impediment to realising their widespread clinical potential. A key factor in assessing the performance of microneedle (MN) patch designs and formulations is their capacity to successfully penetrate into skin. To address this need, I developed a state-of-the-art skin tissue model that reflects in vivo mechanical conditions of the skin, along with a constitutive equation for strain-dependent drug diffusion in tissue. It was experimentally validated using bespoke static 3D-printed Franz diffusion cells (FDCs) to investigate the influence of time-dependent skin strain and deformation on microneedle-based therapeutic delivery. The optimised 3D hyperelastic, anisotropic pre-stressed multi-layered skin material model, developed as part of this thesis, more accurately reflects in vivo skin conditions. It was used to determine that the level of skin tension affects both the microneedle penetration force and insertion efficiency, and quantified how adjacent microneedles impact the overall performance of the microneedle patch. Following on from this model, a further strain dependent transdermal drug delivery model was developed. This was coupled with skin deformation and skin strain due to MN insertion and retention, creating a Multiphysics model. This model indicated that the presence of mechanical strain, due to e.g. compression related to MN insertion significantly alters the permeation through the skin. Furthermore, once the mechanical strain is removed (through removal or dissolution of the MN array), the permeation through the skin will recover. The delivery of high molecular weight compounds may be most susceptible to strain-induced changes in drug permeation. This highlights the importance of microneedle administration modes when targeting, for example, intradermal or transdermal delivery. Histological fluorescent imaging analysis confirmed that the MNPs physically succeed in delivering the compounds with large molecular weights (>500 Daltons) through the transdermal drug delivery system but that their permeation is negatively impacted by the presence of mechanical strain. This resistance to drug permeation can be mitigated through the removal of mechanical strain e.g. through MN retraction or dissolution. Finally, the in vitro skin absorption assays, conducted using bespoke FDCs, experimentally validated the results of the multiphysics modelling
Essays on the Irish Economy and Financial System
No full textThis thesis includes two chapters focused on the role of non-bank entities in the Irish financial system in recent years and a third chapter analyses income mobility dynamics in the Irish economy during a period including the global financial crisis. The first chapter focuses on the role of non-banks in directly providing financing to small and medium enterprises in Ireland. The key interest of this chapter is on the financial stability implications in Ireland of the increased role for non-banks in providing credit directly to SMEs. We assess how non-banks respond, in comparison to banks, to an environment of tighter financial conditions, using data on the universe of lending in Ireland. Our results show that non-banks react more negatively than banks in response to tighter financial conditions. However, once we adjust our specification to account for the significant differences between non-banks lending in Ireland, we show that some non-bank lender types do not contract lending in response to a tightening in financial conditions, while lenders specialised in financing the property market react very negatively, contracting lending strongly in comparison to banks. Our results show the critical importance of looking beyond the binary classification of banks versus non-banks when conducting analysis on how the increased role of non-banks in direct lending may affect financial stability. The second chapter explores whether a change in regulatory status for financial service providers in the non-bank space leads to more favourable outcomes for consumers with respect to the terms on their loan agreements. Specifically, I estimate whether the introduction of consumer protection, or conduct of business, regulation, results in more or less favourable outcomes for consumers with respect to the interest rate charged on their loans, exploiting a regulatory change in the Irish financial system in 2022. I use a difference-in-differences strategy, which allows identification of the effect of the regulatory change on the lending behaviour of firms that became regulated entities during the sample period. The results of this analysis suggest that following the change in legislation which resulted in some entities becoming regulated, the interest rate charged to consumers increased. Thus, the change in regulatory status resulted in less favourable outcomes for consumers. The third chapter provides evidence on how income mobility evolved during from 2005-2014 in Ireland, a period characterised by significant volatility in macroeconomic outcomes. I use an administrative tax data set on the annual earnings of employees in Ireland, which follows the same individuals each year, allowing for an analysis of how individuals move through the income distribution over time. I provide estimates of macromobility measurements from the income mobility literature which estimate income mobility for the entire income distribution, outlining the starkly different outcomes depending on the sub-period in question. I also provide evidence for micromobility, the individual characteristics underlying income mobility. In terms of gross incomes, I find Construction workers were about 3 times more likely to experience a fall in the income distribution than other private sector workers during this period in Ireland. In contrast, public sector workers had lower odds of experiencing a fall in the income distribution. However, when looking at net incomes, which take account of additional levies on public sector salaries, the results suggest public sector workers were not more or less likely that private sector workers to move downwards through the income distribution. This suggests that while public sector workers were unlikely to become unemployed, in terms of net income, working in the public sector did not necessarily protect their relative position in the income distribution
q-Series and Modularity
No full textIn this thesis, we construct two-parameter generalisations of Hecke-Appell type expansions for the generating functions of unimodal and special unimodal sequences. We obtain their explicit representations in terms of mixed false theta series. We use these representations to recover partial theta identities from Ramanujan's lost notebook and in work of Warnaar
Information Dynamics In Controlled And Uncontrolled Quantum Systems
No full textHarnessing quantum phenomena for technological applications relies heavily on preventing information loss through decoherence. To prevent this loss, it is crucial to develop strategies that enable the rapid and precise control of quantum systems, ensuring that desired processes are completed faster than decoherence times. Traditionally, the environment is viewed as a disruptive force; however, this perspective ignores the rich informational dynamics that environmental interactions can induce. By relaxing the requirement for strict control and adopting a more active treatment of the environment, this thesis explores how these dynamics contribute to the emergence of classicality from quantum mechanics, and how it can restructure the internal information structure in quantum many-body systems.
The study begins by addressing the challenges of controlling quantum systems near critical points, where conventional adiabatic methods become inefficient due to closing energy gaps. We propose a novel control strategy that applies counterdiabatic driving selectively within the impulse regime, as recognised by the Kibble-Zurek mechanism. This significantly reduces energetic costs while maintaining high fidelity. This approach is validated both numerically and analytically, demonstrating substantial energetic savings.
Next, we explore control strategies relevant to implementing unitary gates in two distinct physical settings. The first involves analytically determining a Hamiltonian that achieves gate operations with unit fidelity without external control, while the second leverages an auxiliary qubit that requires external driving. Despite the latter scheme being more resource intensive, we show that the additional complexity of driving and controlling an auxiliary qubit can be advantageous when we subject the systems to decoherence.
Moving beyond controlled systems, we examine the informational dynamics of quantum systems fully subject to environmental effects. Here, we investigate scenarios in which systems transition from pure quantum states to classically objective states as predicted by quantum Darwinism. By partitioning the environment into accessible and inaccessible parts, we reveal how the interplay between these partitions determines whether classical objectivity emerges or if the system equilibrates without the redundant encoding of the state of the system into the environment.
Finally, we explore the competition between two sinks for quantum information - decoherence and information scrambling. Information scrambling refers to the flow of initially accessible quantum information into complex many-body correlations with the system itself. Typical measures of scrambling used in closed systems fail to differentiate between the competing effects. We introduce a method for probing information scrambling even in the presence of open system effects, demonstrating that the environment not only acts as a sink for quantum information but also restructures the remaining information, reducing the complexity of the system's dynamics.
Collectively, these findings provide a comprehensive framework for understanding information dynamics in open quantum systems, offering new strategies for preserving quantum coherence and diagnosing the impact of environment on the structure of quantum information
Development of high strength bonding between polymer and magnesium with micro/nano structures and chemical treatment for bioresorbable stent
No full textThe adhesion of polymer coatings to magnesium (Mg) alloys poses a critical challenge in the development of biodegradable drug- or gene-eluting stents. WE43, an Mg-based alloy, offers promising properties such as biocompatibility and biodegradability; however, its rapid corrosion and inadequate polymer-substrate adhesion hinder its application in cardiovascular stents. This research addresses these challenges by employing advanced surface modification techniques to improve polymer adhesion and enhance the overall performance of WE43 stents. Different modification techniques such as anodization, plasma electrolytic oxidation (PEO), and laser ablation—were employed to enhance polymer adhesion and maintain the mechanical integrity and stability of the WE43. The treated surfaces were further coated with polycaprolactone (PCL) using ultrasonic atomization spray techniques to create a biocompatible, hydrophobic barrier that prevents corrosion. The study optimizes spray-coating parameters, such as solution concentration, number of passes, and atomizing power, to achieve uniform coatings with superior mechanical and corrosion properties. Comprehensive characterization techniques, such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), hydrogen evolution tests, and scratch tests, were used to evaluate the surface morphology, chemical composition, corrosion resistance, and adhesion of PCL to the treated alloys. Modified WE43 showed up to 6 times lower corrosion and more than ten times higher adhesion strength for polymer coating. In vitro, biocompatibility tests with human aortic endothelial cells (HAoECs) demonstrated that the surface modifications and coatings enhanced cell viability and adhesion. The findings of this thesis show that the combination of surface treatments and polymer coatings significantly improves the mechanical integrity, corrosion resistance, and biological performance of WE43, advancing its potential as a biodegradable, drug-eluting stent material. This work contributes to the broader field of biomaterials engineering by providing scalable, efficient methods for the development of next-generation cardiovascular devices.2025-10-20 JG: Author's signature removed from PD
Novel mixture models for bounded, high dimensional and dependent omics data
No full textDNA methylation plays a key role in regulating gene expression and organism development and involves adding or removing a methyl group to cytosine-guanine dinucleotide (CpG) sites. Such aberrant methylation changes can silence tumour suppressor genes. Differential analysis, such as identifying differentially methylated CpG sites (DMCs), differentially methylated regions (DMRs) and differentially expressed genes (DEGs) between conditions like benign and tumour samples, can aid in understanding disease progression. Existing statistical methods for differential analysis of unit-interval bounded methylation data often require transformations that reduce biological interpretability. To address this gap, novel mixture models are proposed that are appropriate for analysing beta distributed, high dimensional methylation data and identification of DMCs. Furthermore, spatial correlation is present among the methylation levels of adjacent CpG sites. A hidden Markov model approach is proposed that accounts for spatial dependencies between adjacent CpG sites, allowing the identification of DMCs and DMRs. Moreover, gene expression and methylation are biologically linked, with methylation affecting gene activation or suppression, yet methylation and gene expression data are typically analysed separately. A joint mixture model is proposed to integrate methylation and gene expression data, simultaneously identifying DMCs and DEGs and providing insight to their dependencies, thus providing a comprehensive understanding of the epigenetic and transcriptional landscape. This thesis presents novel mixture models to analyse differential patterns in high-dimensional and dependent omics data, specifically focusing on epigenetic and transcriptomic data. The proposed methods are evaluated through simulation studies and are applied to publicly available cancer datasets. Additionally, open-source R software packages are available to enable broader use of the proposed models
Fact-checking beyond WEIRD countries de-centering mis- and disinformation frameworks
No full textThis doctoral thesis provides an investigation into the understudied landscape of fact-checking practices devised outside the realm of Western, Educated, Industrialized, Rich, and Democratic (WEIRD) countries. Through a sequence of four interconnected papers, the thesis examines how fact-checkers operating in non-WEIRD locations address emerging challenges related to mis- and disinformation in accordance with the characteristics of their geographical contexts. Drawing on a de-westernizing theoretical framework, the thesis aims to fill epistemological gaps left by the prevalent scholarship on fact-checking and mis/disinformation, which largely relies on the ethical principles and professional norms of practitioners situated in WEIRD contexts. The research data comprises an extensive series of qualitative interviews conducted with 37 fact-checking professionals from 35 organizations operating in 27 non-WEIRD countries across 4 continents. The interview data is analyzed through a reflexive thematical analysis approach, focused on cataloguing the metajournalistic discourse of the interview participants. Thus, the thesis is centered at answering the following research questions: 1) What concepts of problematic information do non-WEIRD fact-checkers use to identify mis- and disinformation in relation to their language and culture? 2) What anti-mis- and disinformation frameworks do non-WEIRD fact-checkers develop to address problematic information within their respective contexts? 3) How do social platforms' content governance infrastructures and policies impact the workflows of non-WEIRD fact-checkers? Through the findings and discussions presented in each paper, the thesis sheds novel light on the unique frameworks, strategies, and challenges associated with the normative standards, institutional missions, and adaptations devised by non-WEIRD fact-checking organizations to combat problematic information and maximize their impact on audiences in their information ecosystems. Resultingly. the thesis argues that fact-checking practices outside the WEIRD spectrum show a broad set of normative and ethical orientations that deviate from frameworks focusing on problematic individual behaviour. The thesis concludes by outlining three epistemological and theoretical dimensions that contribute to a ‘de-centering’ perspective on consolidated understandings of fact-checking and problematic information, highlighting the role played by geographical contexts in shaping fact-checking practices: 1) Fact-checking as a Culturally-situated Practice; 2) The Contextual Nature of Mis- and Disinformation; and 3) The Politics of Fact-checking as Content Moderation