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Low redshift post-starburst galaxies host abundant HI reservoirs
Get PDFFunding: SLE and SW are both grateful for funding from NSERC. MJJD acknowledges support from the Spanish grant PID2022-138560NB-I00, funded by MCIN/AEI/10.13039/501100011033/FEDER, EU. JW thanks support of research grants from Ministry of Science and Technology of the People’s Republic of China (NO. 2022YFA1602902), National Science Foundation of China (NO. 12233001), and the China Manned Space Project (No. CMS-CSST-2025-A08). VW acknowledges Science and Technologies Facilities Council (STFC) grant ST/Y00275X/1 and Leverhulme Fellowship RF-2024-589/4.Studying the gas content of post-starburst (PSB) galaxies can provide valuable clues regarding the process of fast quenching. Although previous works have studied the molecular gas content of PSBs, only a handful of HI measurements exist. Here, we present new Five hundred metre Aperture Spherical Telescope (FAST) 21cm observations of 44 PSBs, leading to 43 detections or sensitive upper limits of HI, which we combine with 25 archival measurements, for a total sample of 68 PSB MHI measurements. HI is detected in 57/68 galaxies, with HI masses ranging from MHI ~108.5 up to 1010 M⊙ and gas fractions (fHI = MHI/M⋆) from a few percent up to almost 30 percent. Post-starbursts therefore retain ample atomic gas reservoirs, despite no longer forming stars. By comparing with a stellar mass-matched sample of star-forming galaxies in xGASS, we find that PSBs have, on average, gas fractions lower by ~0.2-0.4 dex, consistent with a mild reduction compared with their progenitor population. However, PSBs show a diversity of HI properties; about half have HI gas masses within the expected scatter of the star-forming population with the remaining 50 per cent up to a factor of 10 more gas-poor. Compared with galaxies in the green valley, about two thirds of PSBs have gas fractions within the expected range, with the remaining third up to a factor of 10 more gas-rich. Our results demonstrate that quenching in PSBs is not the result of wholesale removal of the atomic gas reservoir and that the population has atomic gas fractions that span the range from star-forming to green valley galaxies. We find no correlation between HI gas mass and time since burst; even galaxies a Gyr past their burst can remain HI-normal. The significant gas reservoirs remaining in many PSBs leaves open the possibility for future rekindling of star formation.Peer reviewe
Genome-wide association neural networks identify genes linked to family history of Alzheimer's disease
Get PDFFunding: This work was supported by Alzheimer’s Research UK [grant ID ARUK-PhD2022-031]; King Abdulaziz University and the University of Oxford Centre for Artificial Intelligence in Precision Medicine (KO-CAIPM); Janssen Research and Development (Johnson & Johnson); the John Fell Foundation [grant ID 0010659]; and the Virtual Brain Cloud from European Commission [grant number H2020-SC1-DTH-2018-1]. C.A. is funded by the National Institute for Health Research (NIHR) Oxford Biomedical Research Centre (BRC).Augmenting traditional genome-wide association studies (GWAS) with advanced machine learning algorithms can allow the detection of novel signals in available cohorts. We introduce “genome-wide association neural networks (GWANN)” a novel approach that uses neural networks (NNs) to perform a gene-level association study with family history of Alzheimer’s disease (AD). In UK Biobank, we defined cases (n = 42 110) as those with AD or family history of AD and sampled an equal number of controls. The data was split into an 80:20 ratio of training and testing samples, and GWANN was trained on the former followed by identifying associated genes using its performance on the latter. Our method identified 18 genes to be associated with family history of AD. APOE, BIN1, SORL1, ADAM10, APH1B, and SPI1 have been identified by previous AD GWAS. Among the 12 new genes, PCDH9, NRG3, ROR1, LINGO2, SMYD3, and LRRC7 have been associated with neurofibrillary tangles or phosphorylated tau in previous studies. Furthermore, there is evidence for differential transcriptomic or proteomic expression between AD and healthy brains for 10 of the 12 new genes. A series of post hoc analyses resulted in a significantly enriched protein–protein interaction network (P-value < 1 × 10−16), and enrichment of relevant disease and biological pathways such as focal adhesion (P-value = 1 × 10−4), extracellular matrix organization (P-value = 1 × 10−4), Hippo signaling (P-value = 7 × 10−4), Alzheimer’s disease (P-value = 3 × 10−4), and impaired cognition (P-value = 4 × 10−3). Applying NNs for GWAS illustrates their potential to complement existing algorithms and methods and enable the discovery of new associations without the need to expand existing cohorts.Peer reviewe
Water bodies : coastal expression in ecocinema practice
No full textPositioning coastal ecosystems as particularly vulnerable to severe effects of anthropogenic climate change, this thesis develops a framework for an ecocinema practice which shifts focus away from human perspectives by exploring different rhythms and scales to depict coastal places through film. Using a collaborative and practice-based methodology, I draw on critical theories from ecocinema and the blue humanities to frame my analysis of my own film practice that experiments with a range of formal and conceptual approaches to cultivating a poetic ecocinema. Through critical analysis of a series of case studies and the creation of three short films, the project argues that collaborative methodologies in poetic ecocinema have the potential to widen access to these films and give experiential context to broader theoretical discussions in ecocriticism.
The thesis is organized into three chapters. The first, Margaret Tait’s Film Poems as a Model for Ecological Filmmaking Practice connects ecocritical theories with Margaret Tait’s film poems, arguing that film poetry has the capacity to attune an audience to non-narrative qualities of a subject. The second chapter, Documentary Patience in a time of Environmental Crisis explores the potentially contradictory ideas of patience and urgency applied to ecocinema practice through examining aerial cinematography in relation to histories of colonialism, landscapes, and mapmaking. The third chapter, Underwater Place: Developing a More-than-human Perspective in Ecocinema expands on critiques of visual dominance and control. It suggests that the inherent formal qualities of cinema render it an effective tool for conveying the significance of imagination in representing nonhuman viewpoints in films."This work was supported by the University of St Andrews Department of Film Studies.
This work was supported by the St Andrews Society of North Carolina."--Fundin
Designing MetaHuman-based historical characters in virtual exhibitions and scenes : a case study on St Andrews
Get PDFThe convergence of digital heritage preservation and modern pedagogy informs the creation of historical characters in virtual settings. We proposed a workflow for creating lifelike, interactive characters that enhance the immersive learning experience, focusing on the medieval St Andrews scene as an illustrative case study. These characters, ranging from well-documented historical figures to generalized medieval citizens, are equipped with historically accurate garments and exhibit realistic expressions. The methodology provides a viable solution for educational and cultural institutions, offering a dynamic approach to experience and engage with history. Further, the paper provides an evaluation and discussion on the impact of these virtual characters in enhancing user engagement and learning experience. Our works underscore the transformative potential of VR in heritage preservation and education, paving the way for more dynamic, engaging, and accessible methods of historical education and cultural exploration
What are sub-national island jurisdictions?
Get PDFThere is no consensus about the definition and classification of Sub-National Island Jurisdictions (SNIJs). This may conflate academic and policy analysis and misguide policies to advance development. We review existing definitions and classifications of SNIJs and systematically analyze the criteria used in different studies. Our study finds several inconsistencies in existing lists of entities labelled as SNIJs. This shows it may be helpful to arrive at common ground as to what might constitute an SNIJ. We suggest to define an SNIJ as a non-sovereign populated island territory that possesses some degree of autonomy in a partnership with a parent state. SNIJs have their own identity and culture, which are distinct from the parent state. They often are former colonies and may freely move towards independence. This definition can be used as a starting point for further analysis and of SNIJs that can help study them and design policies that address their challenges.Peer reviewe
Athanor: Local search over abstract constraint specifications
Get PDFFunding: EPSRC (EP/V027182/1, EP/W001977/1); Royal Society University Research Fellowship; Leverhulme Early Career Fellowship.Local search is a common method for solving combinatorial optimisation problems. We focus on general-purpose local search solvers that accept as input a constraint model - a declarative description of a problem consisting of a set of decision variables under a set of constraints. Existing approaches typically take as input models written in solver-independent constraint modelling languages like MiniZinc. The Athanor solver we describe herein differs in that it begins from a specification of a problem in the abstract constraint specification language Essence, which allows problems to be described without commitment to low-level modelling decisions through its support for a rich set of abstract types. The advantage of proceeding from Essence is that the structure apparent in a concise, abstract specification of a problem can be exploited to generate high quality neighbourhoods automatically, avoiding the difficult task of identifying that structure in an equivalent constraint model. Based on the twin benefits of neighbourhoods derived from high level types and the scalability derived by searching directly over those types, our empirical results demonstrate strong performance in practice relative to existing solution methods.Peer reviewe
A neglected Armenian source of the late Umayyad era : the Martyrdom of Vahan of Gołt‘n
Get PDFFunding: Alasdair Grant acknowledges the funding of the Emmy Noether Junior Research Group “Social Contexts of Rebellion in the Early Islamic Period” (SCORE) at the Universität Hamburg, Deutsche Forschungsgemeinschaft project number 437229168. Leone Pecorini Goodall acknowledges the funding of the Scottish Graduate School for Arts and Humanities (SGSAH) Arts and Humanities Research Council (AHRC) Doctoral Training Partnership. Lewis Read acknowledges the funding of the ERC Project “Re-Evaluating the Eleventh Century through Linked Events and Entities” (RELEVEN) at the University of Vienna, Grant Agreement 101002357.The Armenian Martyrdom of Vahan of Gołt‘n, composed in 744 CE, offers a fresh perspective from which to study the Umayyad caliphate. A sophisticated literary composition assembled in a monastic context, the Martyrdom traces contemporary networks of power, communication, and knowledge within and beyond Armenia. As a product of the late Umayyad world, it constitutes a work of major significance for the study of the Umayyad caliphate at large and the caliphal North in particular during the first half of the eighth century. The Martyrdom reveals contemporary Armenian perceptions of Umayyad hegemony, including ʿaṭā (stipend) payments, public executions, conversions, apostasy, contemporary apologetics, and the nature of Caliph Hishām’s court at Ruṣāfa. At the same time, it portrays members of the Armenian elite, lay and clerical, reacting in different ways to new political circumstances. The present article provides the first annotated English translation and extensive thematic introduction to the Martyrdom of Vahan of Gołt‘n, with the aim of making the text accessible to Islamicists and thereby integrating this rich source into discussions of the late Umayyad era.Peer reviewe
Vocal learning in bottlenose dolphins (Tursiops truncatus) : affect, control, and discrimination
No full textThe origin of human language remains one of the biggest unanswered questions in our evolutionary history. One of the fundamental traits of language acquisition is vocal learning. Vocal learning is a rare trait, only present in four mammalian clades outside of humans. This thesis furthers our understanding of the origin of language through a comparative assessment of a vocal learning mammal, the bottlenose dolphin (Tursiops truncatus). Such comparative analyses shed light on what convergent features we share that lead to the evolution of vocal learning and what features have diverged that have contributed to the evolution of language.
Chapters 2 and 3 investigate the ability of a species to produce vocalisations through choice rather than a reflexive or emotionally driven behaviour. I propose a new framework that allows us to measure such vocalisations in an experimental setting, alleviating the pitfalls of previous analysis. I then test whether this framework can be applied in an experimental paradigm using bottlenose dolphins as a subject species. One overlooked component of vocal learning is perception, since it dictates how an individual will model vocal output. Chapter 4 presents the first evidence of the Clever Hans Effect in a bottlenose dolphin, where unconscious cues can lead subjects to the correct answer that has wide implications for the field of animal behaviour. Chapter 5 reviews the ability of a bottlenose dolphin to discriminate between the vocalisations of conspecifics and heterospecifics. Chapter 6 ties together both perception and production as it reveals how dolphins modify the production of both whistles and burst pulses in positive, neutral, and negative affect contexts and their ability to convey internal emotional state to each other."My PhD and associated costs were funded by the Lynch Family Handsel Scholarship to whom I am eternally grateful. This would not have been possible without your incredibly generous donation. Data collection for chapter 6 was also partly supported by the Templeton World Charity Foundation."--Fundin
The impact of Brexit disclosure on trade credit
Get PDFThe Financial Reporting Council (FRC) issued guidance for companies regarding the disclosure of significant changes in principal risks. We explore the nexus between Brexit disclosure and trade credit decisions. Our findings suggest a positive relationship between Brexit disclosure and trade credit decisions; however, this relationship varies across industries. This variation indicates that UK companies are responsive to regulatory requirements and pressures, undertaking the necessary adjustments to minimize their exposure to Brexit-related risks.Peer reviewe
Crises and negotiations in mutual interventions
Get PDFWhy do states that simultaneously support rebel groups in each other’s intrastate conflicts enter negotiations to resolve such mutual interventions? This is an important question, as negotiations between interveners typically lead to negotiated settlements, which in turn tend to make their intrastate conflicts far less deadly. We argue that international crises make negotiations more likely. Crises raise the costs of intervention and often lead potential mediators to put pressure on states to negotiate. Using new monthly data on mutual interventions in Africa, the article shows that crises are indeed significantly associated with the likelihood that negotiations will occur. This finding is robust to using fixed effects and matching. The article contributes to the literature by investigating a widespread though little-studied type of conflict, as well as by studying the impact of state leaders’ crisis perception using a quantitative research design, which helps overcome a methodological limitation seen in previous studies.Peer reviewe
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