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Ethical loneliness and the undermining of social capital : how racism shapes loneliness in three UK Asian communities – a mixed methods study
Get PDFFunding: This study is part of a PhD research grant [Reference number: ES/P000681/1], funded by the Economic and Social Research Council, United Kingdom.Loneliness can have severe health impacts, and ethnic minority groups may face heightened risks due to structural barriers like racism. This study explores the relationship between racism, social capital and loneliness among Chinese, Indian, and Pakistani communities in Britain. Using mixed methods, we analyse secondary data from the Evidence for Equality National Survey (EVENS) and data from qualitative interviews with 20 older adults and 8 key informants. Our findings show that racism not only exacerbates loneliness but also appears to undermine the positive effects of social capital in reducing loneliness. Ethnic bonding does not consistently protect against loneliness; instead, participating rarely in ethnic activity is associated with less loneliness for Chinese and Pakistani people. We find that marginalisation and isolation within ethnic communities, particularly due to socio-economic status, can exacerbate loneliness and, together with limited English proficiency, hinder the building of bridging ties. Furthermore, although a sense of belonging to British society (bridging capital) lowers loneliness, institutional racism undermines this benefit, leading to ethical loneliness – a profound sense of isolation and abandonment. The findings emphasise the need for policies that enhance both ethnic bonding and bridging capital while addressing structural racism and social inequalities.Peer reviewe
Investigation of particle dynamics and energisation processes in models of collapsing magnetic traps with application to solar flares
No full textIn this thesis we examine the energisation of particles in Collapsing Magnetic Trap (CMT) models. It has been suggested that these CMT models may partially explain the energies and distributions of non-thermal particles in solar flares.
We begin by investigating the key energisation mechanisms in simple CMT models, which are betatron acceleration and Fermi acceleration caused by the curvature of loop tops. We then assess the relative importance of these processes in a 2D CMT model, a 2.5D CMT model with a guide field and an untwisting 3D CMT model. In each case, we find that Fermi acceleration becomes more important for particles on the most initially stretched field lines and that betatron acceleration is dominant for particles on field lines that start in a more collapsed state. The guide field introduced in the 2.5D model reduces Fermi acceleration, as field lines become less curved, but increases betatron acceleration for almost all particles. The effect of the untwisting of the 3D field on the relative importance of betatron and Fermi acceleration is less clear, but the overall energising effect of this untwisting is small compared to the collapse of field lines.
Next, we consider the more complicated case of an untwisted 3D CMT model which incorporates a radially-decaying braking jet. The inclusion of this feature gives rise to distinct types of particle orbit and can lead to a sensitive dependence between the initial pitch angle of an orbit and its final energy. Most particles tested gain energy due to both betatron and Fermi acceleration, but some lose energy by becoming loop leg trapped or by experiencing Fermi deceleration at an inwardly curved loop top, deformed by the
braking jet.
Finally, we construct a simplified estimator for particle energisation in both a 2D and untwisted 3D CMT models with the aim of reliably calculating the final energies of particles much faster than with test particle orbits. It works by neglecting the trajectory of the orbit and instead averages the contributions of betatron and Fermi acceleration at a given time, using only the initial conditions of the particle and the properties of the magnetic, electric and velocity fields. The estimator is highly effective for a wide range of particle orbits and represents a significant speed up when compared to a test particle orbit code for both the 2D and untwisted 3D models tested.
Throughout the thesis, we find that while particles can be substantially energised in CMT models, the vast majority of the particle orbits that we investigated experienced only modest energy gains. This indicates that further processes might be needed to produce the observed populations of particle energies
Life through Liturgy : transformations and tradition through Solesmes Benedictinism
Get PDFThis thesis addresses the question of what it might mean to live, learn and relate liturgically. It draws on nine months’ multi-sited fieldwork at several Catholic Benedictine monasteries belonging to the Solesmes Congregation, mainly the Abbaye Saint-Pierre de Solesmes in France, Quarr Abbey in England, and Clear Creek Abbey in Oklahoma, USA.
Following the guidance of the 6th-century Rule of St Benedict, Benedictine monks take life-time vows of stability to a particular community, committing their lives to the worship of God through the traditional Catholic Liturgy. This is performed communally in seven daily “Divine Offices”, said or sung in Gregorian chant from texts comprising mainly psalms and passages from Scripture, with the daily Mass at the heart of the cycle. I describe the ways in which the Liturgy establishes relations of transcendence at the heart of the monks’ lives while forging and reiterating connections between individuals and communities, the monasteries of the Congregation, the wider Church and the world at large, spanning space and time.
Founded in France in 1832, the Solesmes Congregation places a special emphasis on the place of Liturgical worship in a modern, secular context. Across four chapters—Being and becoming, Eating, Praying, Returning home?—I show how the daily Liturgical cycle works to draw monks, guests (including, self-reflexively, anthropologists) and visitors alike, in various ways, into contact with an “enchanted” way of being (an “analogical imagination”—Norget et al. 2017). In an attempt to treat such claims seriously, I treat the monastery as pointing always beyond itself, a metaphor in various guises for the possibility of what Charles Taylor (2007) calls a “fullness of life” in contemporary secular contexts."This work was supported by the Scottish Graduate School of Social Science, ESRC Grant Ref: ES/P000681/1."--Fundin
The impact of violence on the dynamics of migration : evidence from the Mexican Revolution
Get PDFFunding: This research was developed with the financial support of the 2020 Carnevali Research Grant, Economic History Society.Forced displacement from conflict has risen sharply in recent decades, yet little is known about how violence impacts migration dynamics in the short run or over a longer horizon. Using novel high-frequency data during the Mexican Revolution (1910-1917), one of history’s deadliest conflicts, we find that localized violence caused a sharp but temporary 60 percent spike in migration to the US, lasting only seven months before reverting to pre-conflict levels. We do not find evidence of increased migration after the Revolution, suggesting that refugee networks did not spur significant chain migration, even during an era of relatively open borders.Peer reviewe
Non-pharmacological treatment for postural orthostatic tachycardia syndrome : a scoping review protocol
Get PDFObjective: The objective of the review is to systematically map the literature on non-pharmacological interventions for postural orthostatic tachycardia syndrome to identify and categorize interventions used, and highlight research gaps to guide future studies. Introduction: Postural orthostatic tachycardia syndrome is characterized by an excessive increase in heart rate upon standing and symptoms of orthostatic intolerance. Non-pharmacological interventions are first-line treatments; however, the breadth, characteristics, and gaps in the current evidence base have not been systematically mapped, making this scoping review necessary to guide future research directions. Inclusion criteria: Studies on non-drug, non-procedural, and non-invasive interventions for postural orthostatic tachycardia syndrome in both children and adults will be included. Both direct (affecting patients) and indirect (benefiting but not targeting patients) interventions in any setting will be considered. Original research, systematic reviews, meta-analyses, and gray literature will be included. Methods : A comprehensive search will be conducted across 6 databases (Ovid MEDLINE, Ovid Embase, Cochrane Library, CINAHL, Scopus, and Web of Science) and gray literature platforms. Searches will be limited to articles in English, Afrikaans, French, German, and Korean, with no restriction on publication date. Two reviewers will independently screen titles and abstracts, as well as full text, against the inclusion criteria. Data will be extracted using a standardized tool and presented to highlight key findings and research gaps. The initial data extraction form was developed after scanning the literature and will be iteratively refined as part of protocol development. Review registration: Open Science Framework https://osf.io/cg365.Peer reviewe
Domain adaptation for cross-domain alignment in human activity recognition using device-free sensing
Get PDFOver the past years, Wireless-Fidelity (Wi-Fi) sensor-oriented system networks have gained significant attention for conveying information via radio data transmission due to their ease of deployment on a large scale and high throughput yield. Recently, researchers have explored using Wi-Fi signals to track human motion in laboratory environments. These signals fluctuate in response to movement, creating identifiable activity patterns through channel state information (CSI). Such a sensing methodology is gaining popularity among traditional approaches as it is a contactless sensing strategy without requiring wearable sensors and no need to take the personal identity of the user, thus preserving privacy. Also, there are no constraints for lighting around the area or line of sight (LOS) requirements.
This thesis explores both traditional and modern advancements in device-free human activity recognition (HAR), analyzing their strengths and limitations. A significant challenge in this field is the domain-shifting issue, where models trained in one environment fail to adapt to different conditions due to variations in users, surroundings, and atmospheric factors. Existing approaches often lack generalization since models are trained and tested on data collected under similar settings.
To address this, our first solution evaluates inter-domain and intra-domain alignment methods to identify which one is better at robustly matching the source to the target domain. The second approach introduces a supervised domain alignment technique, requiring minimal labeled data to improve recognition accuracy in a new environment. Lastly, we present an unsupervised multi-source domain adaptation method, which aligns diverse data distributions with a target domain affected by new users and environmental variations.
We validate the proposed methods using three HAR CSI datasets, demonstrating significant improvements in transfer learning tasks compared to state-of-the-art baselines. These findings contribute to making Wi-Fi-based HAR more robust and applicable to real-world scenarios
A gold(I)-acetylene complex synthesised using single-crystal reactivity
Get PDFFunding: This work was supported by the European Research Council (ERC Starting Grant, CoopCat, Project 756575) and the Spanish Ministry of Science and Innovation (PID2022-139782NB-I00). M. N. acknowledges the Spanish Ministry of Science and Innovation and Junta de Andalucía for postdoctoral programs (FJC2018-035514-I and DOC_00149). Leverhulme Trust (RPG-2020-184; MRG, CLJ) and the Wild Overseas Scholar's Fund (CLJ); the University of St. Andrews (DJS) and EPSRC (EP/W015498/1, MAS; UK Catalysis Hub, EP/R026815/1, MRG).Using single-crystal to single-crystal solid/gas reactivity the gold(I) acetylene complex [Au( L1 )(η2-HC≡CH)][BArF4] is cleanly synthesized by addition of acetylene gas to single crystals of [Au( L1 )(CO)][BArF4] [ L1 =tris-2-(4,4′-di-tert-butylbiphenyl)phosphine, ArF=3,5-(CF3)2C6H3]. This simplest gold-alkyne complex has been characterized by single crystal X-ray diffraction, solution and solid-state NMR spectroscopy and periodic DFT. Bonding of HC≡CH with [Au( L1 )]+ comprises both σ-donation and π-backdonation with additional dispersion interactions within the cavity-shaped phosphine.Peer reviewe
Integrated CO2 capture and hydrogenation in presence of Ru–Na2ZrO3 : an in-situ study
Get PDFFunding: The research done at the Chemistry Division of Brookhaven National Laboratory was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division, Catalysis Science Program (Grant No DE-SC0012704). This research was partially funded by the UK STFC - ISIS Neutron and Muon Source (award 1920083). This research used resources of beamlines TES and ISS of the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under contract No. DE-SC0012704. C. Emehel thanks the Nigerian Petroleum Technology Development Fund(PTDF) for funding (Award No. 22PHD011).Integrated CO2 capture and conversion (ICCC) by hydrogenation is a promising strategy to utilize carbon dioxide and this work add to the effort to elucidate the catalytic hydrogenation mechanism using Ru based dual functional materials (DFM). Ru–Na2ZrO3 DFMs, obtained through different wet methods, were evaluated for the first time and the relationship between Ru and support systematically investigated. The thermally stable and cyclable Ru–Na2ZrO3-a (obtained without filtration step) exhibited CO2 conversion of 80 % and a higher yield of CO at 400 °C compared to previously tested DFM, while the Na depleted/Zr rich Ru–Na2ZrO3-b resulted in 90 % selectivity to CH4 with yield of 1.11 mmol/g at the same temperature. The in-situ experiments have provided conclusive evidence showing that CO2 hydrogenation on the two Ru DFMs is fundamentally different. In Ru–Na2ZrO3-a, the monoclinic Na2ZrO3 support acted as the active centre (not as promoter) for CO2 bridging binding and hydrogenation to CH4 at the metal-support interface through associative formate pathway with limited further reduction to methane due to lack of H2 spillover from the small and well dispersed Ru NPs, which results in CO desorption. Conversely, abundant clusters of larger Ru NPs in Ru–Na2ZrO3-b, led to CH4 production due to co-existent Ru on-top direct dissociation of CO2 (preferential) and monodentate formate adsorption and further methanation. Alkali zirconates doped metals, and their synthesis method could thus play a crucial role in designing tuneable heterogeneous catalysis in C1 chemistry, which could significantly benefit the environment by lowering CO2 levels, encouraging cleaner industrial practices, supporting a circular economy, and converting waste CO2 into valuable products.Peer reviewe
Influence of Cu on the sustainable synthesis and thermoelectric properties of the half-Heusler TiNiSn
Get PDFFunding: BFK and JWGB acknowledge the EPRSC (EP/Y016459/1) and ILL for award of the beamtime. ABN acknowledges the EPRSC (EP/L017008/1, EP/R023751/1 and EP/T019298/1).Doping of TiNiSn with abundant Cu is highly beneficial for its thermoelectric performance. In situ neutron powder diffraction reveals that the half-Heusler formation reaction is complete within 3–4 h. Using these insights we optimise the synthesis of Cu doped TiNiSn from powder precursors, minimising decomposition, and achieve a high zT = 0.9 at 723 K.Peer reviewe
Ion-rich acceleration during an eruptive flux rope event in a multiple null-point configuration
Get PDFFunding: TW acknowledges DLR grant 50 OC 2301. AJBR and CEP acknowledge support from STFC grants ST/S000402/1 and ST/W001195/1. NVN acknowledges NASA grants 80NSSC23K0408 and 80NSSC24K0175.We report on the γ-ray emission above 100 MeV from the GOES M3.3 flare SOL2012-06-03. The hard X-ray (HXR) and microwave emissions have typical time profiles with a fast rise to a well-defined peak followed by a slower decay. The >100 MeV emission during the prompt phase displayed a double-peaked temporal structure with the first peak following the HXR and microwaves, and the second one, about 3 times stronger, occurring 17 ± 2 s later. The time profiles seem to indicate two separate acceleration mechanisms at work, where the second γ-ray peak reveals a potentially pure or at least largely dominant ion acceleration. The Atmospheric Imaging Assembly imaging shows a bright elliptical ribbon and a transient brightening in the northwestern (NW) region. Nonlinear force-free extrapolations at the time of the impulsive peaks show closed field lines connecting the NW region to the southeastern part of the ribbon, and the magnetic topology revealed clusters of nulls. These observations suggest a spine-and-fan geometry, and based on these observations, we interpret the second γ-ray peak as being due to the predominant acceleration of ions in a region with multiple null points. The >100 MeV emission from this flare also exhibits a delayed phase with an exponential decay of roughly 350 s. We find that the delayed emission is consistent with ions being trapped in a closed flux tube with gradual escape via their loss cone to the chromosphere.Peer reviewe
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