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Monetary Policy Shocks and Exchange Rate Dynamics in Small Open Economies
Get PDFThis paper investigates whether the effects of monetary policy shocks on real exchange rates have changed over time and, if so, whether these changes stem from shifts in transmission mechanisms or from variation in the volatility of the shocks themselves. Using a time‐varying parameter VAR with stochastic volatility for six small open economies, we first show that a constant‐parameter VAR with stochastic volatility provides the best fit to the data in all six cases. We then employ an identification strategy that combines short‐ and long‐run restrictions to isolate monetary policy shocks, and we evaluate its robustness using high‐frequency monetary policy surprises as external instruments. Our results support Dornbusch's overshooting hypothesis in most countries. However, uncovered interest parity is frequently violated, as foreign excess returns diverge from zero following monetary policy shocks. Finally, we document a substantial decline in the volatility of monetary policy shocks since the 1990s, leading to a reduced contribution to exchange rate and macroeconomic fluctuations
Experiences of Women and Clinicians During the Introduction of Uterine Transplantation to the UK: A Qualitative Case Study
Get PDFObjective: To explore the experiences of women and clinicians during the introduction of uterine transplantation (UTx) to the UK. Design: A qualitative study utilising prospective case study methodology (interviews and observations) over 6 years. Setting: In the UK, five uterine transplants have been completed to date—two using living donors and three using deceased donors. In addition, three deceased donor retrievals were undertaken but did not proceed to implantation. Sample: Data included 18 audio‐recorded consultations with potential recipients and clinicians, 22 interviews with seven clinicians and eight follow‐up interviews with women. Methods: Data were synthesised using thematic analytical methods. Results: The first theme, ‘Emotional and ethical dimensions of UTx decision‐making’, explores how women and clinicians navigated uncertainty, risk and hope, including dilemmas around living versus deceased donation. The second, ‘Building and refining a UK UTx programme’, reflects on bridging disciplines, managing initial cases and iteratively improving protocols through teamwork and reflection. The third, ‘Living through the unknowns after transplantation’, captures recipients' post‐operative experiences, their collaboration with clinicians, and uncertainties surrounding recovery, embryo transfer and pregnancy. Conclusion: Prospective qualitative research enabled surgeons to reflect on their practice while generating insights to optimise uterine transplant delivery in the UK and internationally. Findings offer practical guidance for navigating uncertainty and risk when introducing new procedures and highlight ways to strengthen support for women throughout the process. Overall, this study demonstrates how prospective qualitative methods can provide crucial insights into the technical, ethical and emotional dimensions of innovative procedures like UTx
Geodynamic Controls on Mantle Differentiation and Preservation of Long‐Term Geochemical Heterogeneity: Focus on the Primitive Undegassed Mantle
Get PDFPlain Language Summary: Partial melting of mantle materials allows for degassing and creates compositional heterogeneities that can be preserved for several billion years as suggested by geochemical observations. Helium and argon data suggest that heterogeneities, potentially nearly as old as the age of the Earth, undegassed, are preserved within the planet's interior. Previous works have shown that increasing the viscosity or density of mantle materials can help maintaining them from melting and degassing. However, the role of mantle convection in controlling the amount of material processed in melting zones through time (i.e., the processing history) is unclear. Therefore, the influence of fundamental convection parameters (e.g., viscosity, radiogenic heat input) on the processing history are investigated using 3D spherical simulations. The resulting preservation of primitive undegassed material is systematically analyzed. Results show that the processing history relates to the thermal evolution of the mantle and that different types of material are processed depending on surface velocities and shallow temperatures. A preservation mechanism is the dispersal of primitive material by convection, allowing the material's temperature to converge to that of the average mantle. Results show that some geodynamical contexts and processing histories are more favorable to the preservation of material than others
Mechanisms of long-distance navigation and the time-compensated sun compass in wild shearwaters
Get PDFDecades of research have shown that birds attend to the motions of our planet and distant stars to navigate across the earth. Yet how such cues contribute to guiding their natural movements remains largely a mystery because the animal navigation literature has relied heavily on captive or incarcerated birds, motivated to orient either by displacement or migratory restlessness. In this thesis, I utilise the growing body of tracking data from the free-ranging movements of wild shearwaters to investigate the sensory and cognitive mechanisms of a wild avian navigator. I achieve this by leveraging errors inherent in the constraints of putative navigational mechanisms or induced by sensory manipulation. First, I exploit the highly conserved mechanisms of circadian entrainment to predict that Manx shearwaters (Puffinus puffinus) might experience jet-lag-like time shifts during rapid longitudinal flights, causing errors in use of a time-compensated sun compass. These errors reveal that shearwaters use the sun compass to home after their natural foraging trips, apparently as the primary compass cue when out of sight of land, and integrate information from land when coast-following, perhaps by visual pilotage. Further, capitalising on this interaction between use of the sun compass and coast-following, which can be detected without a priori knowledge of the shearwater’s goal, I show that shearwaters use the sun compass while commuting towards foraging grounds. I build on these findings using an artificially induced clock-shift, and show that the timing of shearwaters’ foraging movements is influenced by their endogenous circadian clocks. I next find that shearwaters do not appear to rely on geomagnetic cues to calibrate their time-compensated sun compass, nor indeed for any part of their homing navigation. The last empirical chapter of this thesis investigates the spatial representations which facilitate distance estimation in the migration of Balearic shearwaters (Puffinus mauretanicus), and the contribution of this spatial cognition to individual migratory flexibility and population range shifts under climate change. Finally, I consider surprising parallels to the navigation of homing pigeons (Columba livia) and the implications for the evolution of navigational mechanisms; the value of data on the free-ranging movements of wild birds for investigating navigation, especially beyond homing and migration; and the potential this provides for studying the behavioural ecology of navigational and chronobiological mechanisms
Editorial: Lipids in immunometabolism
Get PDFacids in modulating macrophage phenotype and function. Fatty acids selectively engage pattern recognition receptors, triggering intracellular signalling cascades that rewire cellular energetics and shape macrophage polarization. Expanding this discussion, Juan P. Rodríguez and colleagues consider additional lipid species, including oxylipins and phospholipids, demonstrating that lipids function not only as structural components but also as signalling mediators that influence macrophage behaviour beyond metabolic regulation alone. Together, these studies reveal a complex interdependence between macrophage polarization and lipid phenotype, underscoring the value of integrating lipidomics into multiomic profiling approaches to uncover novel therapeutic strategies for immune-mediated and inflammation-related disorders, including inflammaging. Collectively, the contributions in this issue highlight how altered lipid metabolism and specific lipid species influence immune dysfunction and disease progression across diverse conditions, including metabolic dysfunction-associated fatty liver disease (MAFLD), obesity-related immune impairment, and chronic endometritis. In a large two-stage Chinese study, Zhao et al showed that in MAFLD, the liver's central role in lipid handling means that lipid accumulation provokes systemic inflammation; composite inflammatory markers linked to dysregulated lipid metabolism predict disease risk beyond traditional metabolic parameters, emphasizing that lipid-associated inflammation is integral to pathogenesis. Wilkin et al demonstrated that in obesity, peripheral invariant NKT (iNKT) cells exhibit activation and dysfunction driven by metabolic stress, reflecting broader lipid-mediated immune perturbations characteristic of obese states. Importantly, Matsuda et al showed that in chronic endometritis, dysregulation of SREBP1-a master regulator of lipid biosynthesis-reduces polyunsaturated fatty acids such as EPA in endometrial phospholipids, perpetuating inflammation and increasing miscarriage risk. Notably, dietary EPA supplementation restores lipid balance and mitigates inflammatory pathology, directly linking lipid composition to immune resolution and reproductive outcomes. Taken together, the articles in this collection firmly establish lipids as active regulators of immune cell fate and systemic homeostasis. While targeting anabolic and catabolic pathways offers promising therapeutic avenues, the widespread expression of metabolic enzymes across tissues demands precision-based strategies to minimize off-target effects. As the field of immunometabolism continues to mature, integrating lipid-focused approaches will be essential for translating mechanistic insight into clinical benefit
Toward automated neonatal EEG analysis: multi-center validation of a reliable deep learning pipeline
Get PDFObjectives: To evaluate the reliability and generalization of NeoNaid, a fully automated software tool for neonatal EEG analysis, based on functional brain age (FBA) estimation and sleep staging. Methods: NeoNaid combines a multi-task deep learning model with proposed quality control routines detecting artifacts, out-of-distribution inputs, and uncertain predictions. Based on a raw EEG input, it outputs one global FBA estimate and a continuous 2-state hypnogram. We validated performance on two independent hospital settings: an internal dataset (33 EEGs, 17 infants, median 900 min/recording) and an external dataset (38 EEGs, 24 infants, median 124 min/recording). Results: Quality control rejected a comparable number of segments in the internal and external datasets, reducing extreme errors in FBA estimation, and modestly improving sleep staging accuracy. Across the internal and external data, NeoNaid achieved median absolute FBA errors of 0.50 and 0.55 weeks and Cohen’s Kappa values of 0.89 and 0.87 for quiet sleep detection, respectively. Discussion: NeoNaid demonstrated improved reliability through integrated quality control and maintained performance across two independent datasets. By focusing on validation and trustworthiness, this work takes an essential step toward clinical adoption of automated neonatal EEG analysis and supports its utility for both NICU practice and large-scale research
Decomposition of N = 1 superconformal minimal models and their fractional quantum Hall wavefunctions
Get PDFN = 1 superconformal minimal models are the first series of unitary conformal field theories (CFTs) extending beyond Virasoro algebra. Using coset constructions, we characterize CFTs in N = 1 superconformal minimal models using combinations of a parafermion theory, an Ising theory and a free boson theory. Supercurrent operators in the original theory also becomes sums of operators from each constituent theory. If we take our N = 1 superconformal theories as the neutral part of the edge theory of a fractional quantum Hall state, we present a systematic way of calculating its ground state wavefunction using free field methods. Each ground state wavefunction is known previously as a sum of polynomials with distinct clustering behaviours. Based on our decomposition, we find explicit expressions for each summand polynomial. A brief generalization to S3 minimal models using coset construction is also included
Differentiating ischemic from healthy myocardium using cardiovascular magnetic resonance dipyridamole rest and stress T1 mapping
Get PDFCardiovascular magnetic resonance (CMR) stress T1 mapping using adenosine and regadenoson can differentiate ischemic, infarcted, and healthy myocardium. However, the effect of dipyridamole remains unclear. This study evaluates whether dipyridamole-induced stress T1-mapping can distinguish myocardial tissue types. Twenty-five healthy controls and 20 patients with coronary artery disease (CAD) underwent rest and dipyridamole stress T1-mapping (ShMOLLI), followed by gadolinium-based quantitative perfusion imaging at 1.5T. Native T1 values and stress T1 reactivity (dT1) were assessed across different myocardial tissues. Correlations between dT1 and myocardial blood flow (MBF) were examined. In healthy controls, global rest T1 was 934 ± 26ms, with a stress-induced increase of 6.5 ± 0.6% (p 0.05) but reduced stress reactivity (dT1 = 4.5 ± 1.1%; p < 0.0001) compared to norm. dT1 strongly correlated with stress MBF (r = 0.80) and myocardial perfusion reserve (r = 0.70) (both p < 0.0001). Dipyridamole-induced stress T1-mapping can differentiate infarcted, ischemic, and healthy myocardium, supporting its use in non-contrast CMR for myocardial tissue characterization
Learning from the input: a corpus-based investigation of Chinese classifiers in children’s books and child-directed speech
No full textIn Mandarin Chinese, numeral classifiers form a grammatical category that is syntactically obligatory when a noun is modified by a numeral or a demonstrative. The appropriate choice of a classifier is associated with the semantic properties of its corresponding noun and is context dependent. Experience with language is needed to learn these patterns, but little is known about how classifiers are structured in children’s language environments. We compared the frequency and distribution of classifier phrases in four corpora: child-directed speech, children’s television shows, children’s books, and adult-directed speech. Classifier usage in children’s books was more diverse than in both child-directed and adult speech. Books contained more specific classifiers that co-occurred with a higher proportion of unique nouns whereas everyday speech relied on more generic classifiers. Books therefore provide access to classifier-noun collocations that are rare in speech. Implications for language development and language processing are discussed