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Resonance free domain for Dirac equation with mass type potentials
No full textWe establish an a priori estimate, a microlocally exponential weighted estimate, for the three-dimensional
Dirac operator perturbed by a (full) matrix-valued, long-range potential which is not necessarily analytic on all of but only outside some compact set. As an application we show the existence of a resonance free domain on the nontrapping energy surface for a Dirac operator with a mass type potential. The latter result is based on a positive lower bound of the asymptotic expansion of the deformed eigenvalues on an I-Lagrangian manifold.</p
Delegitimating youth in Thai politics through discursive representation of the Future Forward Party (FWP)
No full textThis thesis investigates how the Future Forward Party (FWP), a youth-led political party in Thailand, was discursively delegitimated in both media and parliamentary domains between 2018 and 2020. As a newly formed party with a progressive agenda and young executive members, the FWP presented a unique challenge to Thailand’s traditional political landscape, which has long been shaped by seniority norms, military influence, and the patronage system. While youth participation in Thai politics is often associated with activism and protest movements, this study focuses on institutional politics, where young politicians continue to face both overt and subtle exclusion.Adopting a multi-method approach, this study employs Corpus-Assisted Discourse Studies (CADS) to analyze 399 articles from the right-leaning English-language outlet Nation Thailand*, as well as eight parliamentary debate sessions involving FWP Members of Parliament. Van Leeuwen’s (de)legitimation framework was used to identify delegitimating strategies across both domains, while Culpeper’s implicational impoliteness model helped interpret indirect face-attacking strategies in parliamentary discourse.Findings revealed that delegitimation in the newspaper domain relied on subtle forms of faint praise and implication. Terms such as handsome, billionaire, and daddy were associated with FWP leader Thanathorn Juangroongruangkit, often emphasising appearance over political merit. Six discursive frames emerged in the media representations of the FWP: irrationality and superficiality, inadequacy, political apathy, illegality, manipulation, and the generation gap. These frames not only delegitimated the party but also its young voter base.In contrast, parliamentary debates exhibited more adversarial delegitimation through implicatures. Due to the parliamentary code of conduct, MPs employed indirect language or implicatures to undermine the FWP’s credibility. Two overarching impoliteness metalanguage were identified: characteristics and actions. Within these, FWP MPs were frequently framed as inexperienced, impractical, disrespectful of traditions, foreign, uncooperative, and even seditious. The coalition government positioned itself as the ingroup through moral evaluation, seniority-based authority, and nationalist discourses.The study contributes context-specific insights into how youth and experience were strategically used to delegitimate young politicians within a formal political institution. It also highlights the challenges young political actors face when entering a political sphere dominated by conservative norms and entrenched hierarchies. This research advances our understanding of discursive representation, (de)legitimation, and generational exclusion in institutional politics.</p
Quantifying Heteroscedasticity in Linear Models Using Quantile LOWESS Intervals
No full textOrdinary Least Squares (OLS) estimation, which is frequently applied in psychology, assumes constant variance of errors across predictor levels. This assumption is known as homoscedasticity, while its violation is referred to as heteroscedasticity. In categorical predictors, heteroscedasticity can be quantified by calculating the ratio of variances across groups. For continuous predictors, diagnostic residual plots are often used to assess whether the assumption had been met, but there is currently no measure that can quantify the amount of heteroscedasticity in an interpretable way. In this study, we have developed and evaluated a measure that constructs a quantile LOWESS interval (QLI) around the residuals and estimates the linear, quadratic, cubic and quartic change in the width of this interval as a function of the predictor or the fitted values. Further, we evaluated simple linear models under different patterns of heteroscedasticity in a simulation in order to provide benchmark values of QLI estimates associated with inadequate control over false-positive results, loss of power, and loss of coverage probability of confidence intervals. The QLI method provided consistent estimates of trends for models with 60 or more cases, and this was true across variance patterns. We discuss QLI-generated estimates in relation to performance of OLS linear models. Finally, we present an example of how to apply the QLI method to quantify heteroscedasticity and how to interpret the estimates it provides, focusing on the implications for the OLS analysis.</p
Capitalism’s systemic barriers to environmental upgrading in global value chains
No full textWithin the Global Value Chain (GVC) research and policy community the profundity of the environmental crisis is increasingly recognised. In response, scholars advocate environmental upgrading (EnvU) to reduce GVCs’ deleterious environmental impacts. This article argues that the EnvU notion obscures GVCs’ systemically destructive effect upon the natural environment. It is rooted in methodological singularism (analytically focussing upon single chains or firms), eschews a rigorous conception of capitalist relations of production and growth, and does not recognise the specificity of capitalist GVC’s relation to, and destruction of, nature. In contrast, we provide the beginnings of an alternative conceptual framework for comprehending and analysing the environmental impacts of capitalist GVCs. We illustrate our argument through a discussion of the feed-meat value chain—as an indicative example pointing towards directions for future research.</p
Targeting the p53 cancer mutants Y220C, Y220N, and Y220S with the small-molecule stabilizer rezatapopt
No full textThe cavity-creating p53 cancer mutation Y220C, which accounts for an estimated 125,000 new cancer cases per year, serves as an excellent paradigm for the development of mutant p53 reactivators. Several molecules that reactivate this thermolabile cancer mutant by targeting the mutation-induced crevice have been developed, and one of them, rezatapopt, is currently in clinical trials. The less frequently occurring Y220N and Y220S mutations are even more destabilizing than Y220C but create a similar surface crevice, raising the question of whether cancer patients with these mutations might also benefit from rezatapopt treatment. Here, we show that rezatapopt also binds to the Y220N and Y220S mutants, with nanomolar affinity, resulting in a full recovery of wild-type-like stability for the latter. High-resolution crystal structures of all three mutants bound to rezatapopt revealed a conserved binding mode, highlighting key interactions, including multipolar interactions of a fluorine substituent at a chiral center with the protein backbone. Consistent with the biophysical and structural data, rezatapopt reactivated p53 signaling in both Y220C and Y220S mutant cells by restoring the folded conformation and transcriptional activity, leading to anti-proliferative effects and apoptosis, albeit requiring higher compound concentrations in Y220S cells. The Y220N mutant, despite exhibiting high-nanomolar affinity for rezatapopt and substantial stabilization, did not show noticeable effects in cells at the concentrations tested, as rezatapopt binding resulted in only partial compensation for the mutation-induced loss of stability, for which we provide a structural explanation. Our data suggest that the development of clinical pan-Y220C/N/S reactivators, which could benefit an additional 10,000 patients per year, is challenging but not impossible.</p
Dissecting performative prediction: a comprehensive survey
No full textThe field of performative prediction had its beginnings in 2020 with the seminal paper "Performative Prediction" by Perdomo et al., which established a novel machine learning setup where the deployment of a predictive model causes a distribution shift in the environment, which in turn causes a mismatch between the distribution expected by the predictive model and the real distribution. This shift is defined by a so-called distribution map. In the half-decade since, a literature has emerged which has, among other things, introduced new solution concepts to the original setup, extended the setup, offered new theoretical analyses, and examined the intersection of performative prediction and other established fields. In this survey, we first lay out the performative prediction setting and explain the different optimization targets: performative stability and performative optimality. We introduce a new way of classifying different performative prediction settings, based on how much information is available about the distribution map. We survey existing implementations of distribution maps and existing methods to address the problem of performative prediction, while examining different ways to categorize them. Finally, we point out known and previously unknown connections that can be drawn to other fields, in the hopes of stimulating future research.</p
Maternal outcomes associated with delayed cord clamping in hypertensive disorders of pregnancy: a cross-sectional study
No full textBackground/Objectives: Delayed umbilical cord clamping (DCC) is widely recommended for neonatal benefit; however, concerns persist among professionals that DCC may increase the risk of postpartum hemorrhage. There is a higher risk of postpartum hemorrhage in women with hypertensive disorders of pregnancy (HDP). We aimed to evaluate the association between umbilical cord clamping timing and maternal blood loss in term pregnancies, including those complicated by HDP. Methods: We conducted a cross-sectional study of women delivering at three major hospitals in Almaty, Kazakhstan (August 2020–March 2021). The primary outcome was maternal blood loss. Secondary outcomes included hemoglobin (Hb) and red blood cell (RBC) change from pre-delivery to discharge. Multivariable models were adjusted for maternal age, parity and hypertension category. Results: Two hundred and seven women were analyzed (early cord clamping ≤ 60 (ECC) n = 21; delayed cord clamping 60–119 s (DCC60s) n = 161; delayed cord clamping ≥ 120 s (DCC120s) n = 25). Baseline characteristics were similar across groups except for hypertension distribution. Median blood loss did not differ significantly (255–260 mL; p = 0.9128). Adjusted models confirmed no association between clamping category and blood loss (RoM: ECC vs. DCC60s 0.97; 95% CI 0.93–1.01; DCC120s vs. DCC60s 1.01; 95% CI 0.96–1.07). Conclusions: Among term births in Almaty, including HDP-affected pregnancies, delayed umbilical cord clamping was not associated with increased maternal blood loss or hematologic decline. These findings indicate that DCC does not appear to increase maternal bleeding risk in high-risk obstetric populations and are broadly in line with current international recommendations. Further prospective research is warranted to evaluate specific subgroups, including severe preeclampsia.</p
[Commentary] The role of microbial genomics in delivering the UK’s national action plan for confronting antimicrobial resistance 2024–29
No full textAntimicrobial resistance (AMR) is a major threat to human and animal health, in addition to environmental resilience. Countries set the agenda on their national action against AMR in the form of National Action Plans (NAPs), with the UK’s latest NAP released in May, 2024. Advances in genomics have strengthened our ability to work towards NAP priorities; however, to date, no mapping of the role genomics plays in contributing to specific goals within the NAP has been undertaken. The UK Research and Innovation-funded Transdisciplinary Antimicrobial Resistance Genomics Network brought together a range of stakeholders to discuss the role of genomics for action on AMR and to deliver policy priority-led research, as outlined in the UK NAP 2024–29. We report our discussions in this Personal View, with key roles for genomics, including informing targeted stewardship in health-care settings, supporting AMR literacy, and supporting effective antimicrobial innovation. However, changes in infrastructure, communication, and cross-sector coordination are needed to support implementation.</p