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Machine learning-based identification of key electromyography and kinematic features for chronic neck pain classification
Get PDFIn the realm of neck pain management, researchers and medical professionals are constantly exploring new methods. This includes better assessments of pain and related mobility issues, as well as enhancing treatment to improve the recovery of individuals with neck pain. This thesis centres on the utilisation of machine learning (ML) techniques to investigate how electromyography (EMG) and kinematic features can be used to classify people with or without chronic neck pain as this may ultimately guide improved assessment and management of patients with neck pain disorders and associated movement impairments.
Specifically, the objective of this research is to develop a deeper understanding of how EMG signals and kinematic measurements differ between people with and without chronic neck pain and how such data can be used for classification purposes. By analysing and identifying patterns within these data streams, valuable insights can potentially be gained to aid in the assessment, and treatment of neck pain conditions.
To achieve this goal, a comprehensive literature review of relevant studies on neck pain assessment and ML applications was conducted (Chapter 1). Various EMG and kinematic datasets were then collected from participants with and without chronic neck pain, and appropriate feature extraction techniques were applied. ML algorithms were then employed to classify groups with and without neck pain and then, identify key EMG and kinematic features (Chapter 2). These methodologies were examined across diverse tasks, including dynamic contractions of the neck (Chapter 3), static posture (Chapter 4), and gait (Chapter 5).
The results of this thesis showed, firstly, the ability of different ML algorithms to accurately classify people with chronic neck pain compared to healthy individuals across a wide variety of tasks. Secondly, the results identified and highlighted key EMG and kinematic characteristics that improved the performance of all algorithms. These characteristics provide insights into potential muscle activity as well as movement anomalies that are present in people with chronic neck pain. These findings offer a significant step forward in the understanding of the biomechanical and neuromuscular differences in individuals with neck pain compared to pain-free individuals. Additionally, the identified EMG and kinematic characteristics can potentially serve as a foundation for the development of targeted rehabilitation protocols, aiming to address the specific neuromuscular and movement abnormalities found in patients with chronic neck pain. Future research can delve deeper into the causal relationships between these identified characteristics and the presence of neck pain, potentially leading to preventive strategies and interventions
Development of an optical device for therapeutics and diagnostics in neurotrauma
No full textNeurotrauma (traumatic injury to the brain or spinal cord) is a global health challenge and major cause of death and disability. Pharmacological therapies, typically targeting single receptors or pathways, have thus far proven unable to significantly affect the multitude of pathophysiological mechanisms required to promote effective repair. Photobiomodulation (PBM) is a therapeutic approach using red/near-infrared light to promote recovery after injury by mitigating neuroinflammation and preventing neuronal apoptosis. Whilst there is growing evidence for the efficacy of PBM in neurotrauma, two key translational barriers exist: (1) the ability to deliver effective doses transcutaneously to injured tissue within the CNS of humans is severely limited; and (2) there is no currently available means to monitor the therapeutic response to PBM in order to optimise dose delivery. As such, this thesis seeks to develop a medical device which can address these barriers: an implant, composed of optical fibres, which is capable of both delivering PBM directly to injured tissue; and monitor the response to therapy using Raman spectroscopy (RS).
A systematic review of the literature identified key components of effective PBM in traumatic brain injury (TBI): use of 660 nm or 810 nm wavelengths; short duration of treatment; and early implementation post-injury. Using an experimental rat model of spinal cord injury (SCI), 660 nm PBM (24.4 mW/cm, 60 s, daily for 7 days) was shown to improve functional recovery, lesion size and axonal regeneration after SCI, and delivery of PBM using an implantable device improved early expression of regeneration-associated proteins. Raman spectral differences were identified between injury conditions. Using a rat model of mild TBI, 810 nm transcranial PBM was superior to 660 nm PBM, alone and in combination (20.0 mW/cm, 120 s, daily for 3 days), and resulted in improvements in functional recovery. PBM reduced astrocyte and microglial activation after TBI, and treatment was identifiable by spectral biomarkers monitored using RS. Investigation of the mechanisms of PBM demonstrated that 660 nm PBM reduces neuroinflammation in microglia in vitro. Transcriptomics and pathway analysis of 660 nm PBM vs no treatment in the injured spinal cord demonstrated significant upregulation of regeneration associated pathways, and downregulation of key apoptotic genes. This was accompanied by reduced transcription of mitochondrial components and ribosomal transcription, supporting a metabolic mechanism for PBM which leads to neuroprotective and restorative effects. Development of prototype devices demonstrated that effective doses of PBM can be delivered to the brain and spinal cord, using optical fibres integrated into clinically-feasible implantation methods. Lensing and spatial distribution of fibres improved PBM distribution to maximise the volume of injured tissue exposed to treatment.
The work presented here demonstrates proof-of-concept for implantable PBM delivery, with monitoring of effect using RS. Beneficial effects have been demonstrated in both TBI and SCI, and the doses to achieve these effects are deliverable using the developed prototype. RS has been demonstrated as a suitable tool to identify biomarkers associated with successful and effective PBM therapy. This supports the subsequent development of a full device prototype, suitable for use in first-in-human study, toward the translation of this device for clinical trials
The emotional geographies of expectant fathering
Get PDFPregnancy, and the transition to parenthood are intensely emotional experiences and inherently gendered periods of change. Feminist geographers have convincingly situated family/parenting as fundamentally spatial practices, with the transition to parenthood being associated with a unique array of spaces/places and changes to spatial routines. Yet despite a wealth of literature on pregnancy/maternities, and emerging/increasing work on fathering, the experiences of expectant fathers have, heretofore, been largely absent. Drawing upon periodic in-depth interviews, conducted between January 2021 – May 2022 with nine expectant fathers in the UK (most living in England), this research explores the lived, emotional geographies of expectant fathering.
Importantly, this research was conducted amidst the coronavirus pandemic, which saw widespread disruption to ‘normal’ spatial mobilities and routines. Interview narratives are therefore contextualised via broader social-media analyses of the pandemic experiences of UK expectant mothers/fathers. This research brings together, and contributes to, the critical junctures of geographies of family/parenting, emotional and embodied geographies, and political geographic research on (anticipatory) emotional governance, facilitating unique, critical insight into the emotional and spatial experiences of expectant fatherhood in an era of crisis. In so doing, it situates expectant fathering as a daily emotional practice, negotiated and contested across different spaces and, importantly, at different scales – from bodies, homes, and into workplace spaces, mediated also by national policy and legislation. Ultimately, it reveals how fathering, and the evolving identities of expectant fathers are always already shaped by cultural discourses/expectations around masculinity in particular places, by (in)dependence, and by state-citizen relations within specific spaces of healthcare, employment rights/flexibility and welfare, exacerbated in periods of crisis
Synthesis and application of a highly fluorinated ether molecule as an electrolyte co-solvent for enhanced performance rechargeable lithium batteries
Get PDFThe demand for high-performance energy storage systems has driven significant research efforts in the field of secondary lithium batteries. As one of the key components of these batteries, electrolytes play a crucial role in determining their electrochemical performance and stability. In this thesis, a novel electrolyte has been explored to address the challenges and limitations associated with conventional electrolyte systems, which are described in Chapter 1. These challenges and limitations include compatibility issues with high-voltage cathodes, lithium metal anode, and graphite anode, as well as the electrolyte's high-voltage tolerance and stability under high temperature. These issues are critical factors that need to be addressed in battery technology development, as they are essential for improving battery performance and safety. Given the critical role of the solid electrolyte interphase (SEI) and cathode electrolyte interface (CEI) on electrode surfaces in influencing battery cycling, this thesis endeavours to develop and design an electrolyte that fosters the creation of highly stable SEI and CEI layers. The primary goal is to render this electrolyte compatible with high-energy-density, high-voltage lithium metal batteries initially, and subsequently expand its applicability to a broader range of electrode materials and operating temperatures.
The methods and approaches utilized in the thesis are presented in Chapter 2.
Localized high-concentration electrolytes (LHCE) exhibit excellent compatibility with both the lithium metal anode and the high-voltage cathodes. In Chapter 3, the development of LHCE is delved into, utilizing the meticulously designed and synthesized molecule, TTME (1,1,1-trifluoro-2-[(2,2,2-trifluoroethoxy) methoxy] ethane). The symmetrical structure of TTME reduces the overall molecule's polarity, thereby endowing it with diluent-like properties akin to traditional localized high-concentration electrolytes. Additionally, the competitive interaction between the strong electronegativity of oxygen and the -CF3 group allows TTME to partially participate in the solvation structure of Li+ ions. The unique solvation structure of TTME facilitated the coordination of Li+ ions, providing insights into electrolyte design.
In Chapter 4, the performance of TTME-d electrolyte, consisting of 1.4 M LiFSI and DME-TTME (1:4 by volume of 1,2-Dimethoxyethane and TTME) was investigated and found to have excellent electrochemical performance. Lithium metal cells made using this electrolyte demonstrated excellent stability, forming a double-layer SEI structure on the lithium metal surface, which can inhibit dendrite growth and ensure good cycling performance of lithium metal batteries. Additionally, this electrolyte can also generate a more stable CEI film on the cathode side, which helps prevent cathode pulverization and inhibits the dissolution of transition metal ions, thereby extending the cycling capacity.
Chapter 5 explored the co-intercalation of DME with graphite in Li||graphite cells using the TTME-d electrolyte, leading to stabilized performance and capacity retention. The fluorinated ether electrolyte system exhibited superior stability compared to the conventional carbonate electrolyte, showing promise for high-voltage applications such as electric vehicles. Large-capacity NCM811||graphite pouch cells, utilizing the fluorinated ether electrolyte outperformed cells with a carbonate electrolyte under different temperature conditions were tested, and found to retain 91.7% capacity after 300 cycles.
Overall, the insights gained from this research provide valuable contributions to the field of secondary lithium batteries, particularly in the area of advanced electrolyte systems. The exceptional solvation structure of TTME, along with the formation of robust SEI on both anode and cathode, has opened new avenues for the design and optimization of electrolytes to meet the growing demand for high-performance energy storage technologies in various applications. These findings contribute to the development of more efficient and reliable secondary lithium batteries, bringing us closer to a sustainable and greener future
A person-centred approach to understanding athlete mental health and emotional regulation
Get PDFThe aim of this thesis was to investigate student-athletes’ complete mental health and how emotion regulation relates to key indicators of mental health: sport mental well-being and symptoms of mental illness. Following an overview of the mental health and emotional regulation literature in sport and broader psychology in Chapter 1, Chapter 2 narratively synthesized findings from a systematic review investigating the performance and mental health correlates of emotion regulation strategy use for athletes. With 13 studies meeting the inclusion criteria, key gaps were identified: (1) limited consistency in the conceptualization and measurement of mental health and emotion regulation, (2) a lack of literature investigating mental health from a complete state perspective, and (3) limited research on the exploration of a range of emotion regulation strategies. Chapter 3 began to address these gaps and investigated student-athletes’ complete mental health by exploring latent mental health profiles based on patterns in mental well-being, anxiety, and depressive symptoms using latent profile analysis (LPA). The chapter also explored differences in behavioral emotion regulation strategy use and alexithymia between profiles. Chapter 4 replicated the findings of the LPA from Chapter 3, but extended knowledge on differences in other cognitive and behavioral emotion regulation strategies. Chapter 5 furthered knowledge on student-athletes' complete mental health by longitudinally investigating the stability of mental health profile membership and the associations with emotion regulation use to help explain why and how some student-athletes experienced changes and others remained stable in their profile membership. Finally, Chapter 6 included a research note that occurred as an unexpected consequence of the COVID-19 pandemic. The pandemic provided an opportunity to explore student-athletes’ symptoms of mental illness when key features of the sport environment were removed. Overall, this thesis makes novel contributions to the sport mental health literature by exploring student-athlete mental health from a complete state perspective and providing evidence for the association of a wider range of emotion regulation strategy use on indicators of mental well-being, anxiety, and depressive symptoms in this unique population
Using hierarchy and directionality to study the structure and dynamics of Directed Complex Networks
Get PDFA huge range of vitally important systems from social to biological and from economic to technological can be represented as complex networks hence it is crucial to understand the dynamics and structure of these networks. Many real-world interactions are also intrinsically directed and hence best represented by directed networks. Directed networks admit unique features such as the fact that the edges may align with a global direction. We use the recent methodology of Trophic Analysis to show how the directional hierarchy in directed networks affects the structure and dynamics on these networks. In this work, we review the range of techniques used to quantify hierarchy in directed networks. We show how hierarchy relates to the emergence of strongly connected components in real networks. We relate hierarchical structure to the performance of directed Hopfield-like networks and the ability of a network to be influenced by a small number of nodes. We further analyse how hierarchy can arise in networks by studying a fitness-based generative model and how the properties of the generative model relate to the structures measured via Trophic Analysis. This thesis furthers our understanding of how the behaviour of directed networks relates to their hierarchical organisation and global directionality
Characterising the immune environment in metastatic niches in ovarian cancer
Get PDFOvarian cancer (OvCa) continues to be a clinical challenge, with patients often presenting at late stage, and with a high occurrence of relapse and chemoresistance. The tumour microenvironment (TME) of the sites of metastasis in the omentum consists of a complex system of stromal, mesothelial, endothelial, and immune cells that echo the structure of secondary lymphoid organs and facilitate tumour spread and disease progression. This study aims to characterise the stromal cells in the TME, and further elucidate the immune-stromal interactions within the ovarian metastasis TME using C57BL/6J, DARE and IL-33 reporter murine models and human patient samples. Flow cytometry and Multiplex immunofluorescent microscopy were utilised in this study. PDPN-CD31- stromal populations expressing low amounts of FAP and CD140a are potential cancer-associated fibroblasts (CAFs) that may be involved in the direct progression of metastasis. There was also an increase in M1/M2 macrophages and cDC2 dendritic cells in metastatic omentum when compared to healthy omentum, parallel to an increase in cDC2 cells in DARE mice compared to the WT, which leads us to conclude that there is an increased immune activity within metastatic FALCs prior to chemotherapy, however more studies need to be conducted to determine if this activity is anti- or pro- high grade serous OvCa (HGSOC) tumoural proliferation
Female entrepreneurs’ access to capital in Saudi Arabia
Get PDFEfforts to empower women for economic development are a global priority, notably in Saudi Arabia following Vision 2030, where promoting female entrepreneurship is key. However, accessing start-up capital remains a major challenge for many women, with only a small fraction able to transition from intention to business. Research exploring this issue draws from theories like the Entrepreneurship Variant of the Resource-based Theory (EVRBT) and the feminist theory of intersectionality. While past studies highlight barriers and stereotypes hindering female entrepreneurship, there is a gap in understanding how women challenge these stereotypes, navigate barriers, access capital, and establish businesses, influenced by national policies according to their intersectionality characteristics.
Consequently, this study aimed to examine the impact of Saudi national policy on female Entrepreneurs, their challenges in accessing capital, barriers to funding, processes for obtaining resources, and how their unique identities and experiences shaped their entrepreneurial journey. Ultimately, the research sought to address gaps in understanding the dynamic intersecting identities and experiences, including age, marital status, network, family support, occupational stereotyping, and cultural influence. Through qualitative interviews with 32 Saudi female entrepreneurs, the research identified a shift in policy post-2016, creating a more conducive environment for female entrepreneurship. Despite reforms, women still faced various barriers post-establishment, including stakeholder, cultural, and environmental challenges.
Women employed diverse strategies to access different forms of capital, as per EVRBT, with older entrepreneurs leveraging savings and networks more effectively. Younger entrepreneurs relied on family and cultural capital. However, women from conservative backgrounds or unsupportive marital situations lacked family support. Entrepreneurs followed six pathways to establish businesses, with older, married women often shifting pathways after initial ventures. This dynamic process highlighted the role of intersectionality role but also revealed inconsistencies, challenging theoretical assertions.
Overall, the study contributes to extending the existing body of knowledge by enriching it with an intersectionality analysis of how women challenge stereotypes to become entrepreneurs, the hindrances they face, the processes they use to access capital, the pathways they follow to establish new enterprises, and how national policy influences their entrepreneurial initiatives in the context of Saudi Arabia. It contributes to theory by recommending extending the entrepreneurship variant of resource-based theory by including extra types of capital. Another contribution to theory is a recommendation to include intra-sectionality and other factors “intersectionality plus” in the feminist theory of intersectionality. The study also explains how women can challenge stereotypes held against them to become entrepreneurs. Practically, the study contributes to policy and managerial remedies that can be adopted in Saudi Arabia to address personal weaknesses, environmental, stakeholder, cultural, gender, and occupational stereotypes as well as challenges still lingering and hindering women’s success as entrepreneurs even after undertaking varied policy reforms
John Donne and music
Get PDFThis thesis explores John Donne’s engagement with music through his life, writing and the setting of his lyrics to music. It argues that Donne was more involved with music than previously thought. Donne’s encounter with music appears to have begun at a young age, fostered at home, nurtured through relationships (family, friends, patrons, peers) and shaped by experiences (listening to music, playing music, and commissioning music when Dean of St. Paul’s). Examples of musical references and figurative language in Donne’s poetry and prose reveal a musically trained mind. Donne’s social and professional connections with the foremost composers and musicians of his time establish his association with key figures in early modern English musical culture. My analysis of the surviving repertoire of seventeenth-century musical settings of Donne’s poetry explores the relationship of those settings to literary and musical genres, and to broader social and cultural contexts in early modern England and Europe. Significant changes in musical style and literary taste in the culture of the period are reflected in the different ways in which Donne’s poems were set to music. The musical settings of Donne’s poetry also show how characteristic features of his verse – rhythmical, thematic, and imagistic counterpoint and even discord – are refashioned and re-presented in musical performance. The considerable number of Donne’s poems that were set to music by composers evince the impact his lyric poetry had on the musical culture of the early to mid-seventeenth century. Based on manuscript and printed evidence, I argue that Donne’s affinity for music is most evident in those of his lyric poems titled, in manuscript and print, as ‘Songes’ or ‘Songs’, melodic lyrics that were meant to be sung as well as read. By situating this group of poems in the context of early seventeenth century English musical culture and performance, this thesis prompts us to re-evaluate our reading of Donne’s ‘Songes/Songs,’ our view of Donne’s engagement with musical culture, and indeed of his musicality
Macroevolutionary trends in Palaeozoic actinopterygians
Get PDFThe Actinopterygii (ray-finned fishes) are a highly successful group of bony fish that dominate modern-day aquatic vertebrate faunas. Though ubiquitous today, actinopterygians were a minor component of fish faunas during the Devonian ‘Age of Fishes’, when they were overshadowed by agnathans, placoderms and sarcopterygians. The Devonian to Carboniferous transition saw a major shift, with extinctions of placoderms and sarcopterygians paving the way for the diversification of actinopterygians and their establishment as the primary group of fishes by the end of the Permian. The mechanisms of this rise and lasting dominance through the Palaeozoic are poorly understood, however, a suite of compounding factors obscure early actinopterygian spatiotemporal diversity trends, character evolution and relationships. This thesis presents a comprehensive database of Palaeozoic actinopterygian occurrences, identifying major sampling and taxonomic biases influencing face-value trends in diversity. Trends generally track sampling, and there is overwhelming geographic bias towards Europe and North America. Biases are so prolific that sampling standardisation methods fail to recover biologically meaningful palaeodiversity trends beyond a genuine increase following the end-Devonian mass extinction. A small number of poorly defined, widespread genera mask significant taxonomic and morphological diversity. Description of two Carboniferous actinopterygians using CT scanning reveals hidden morphologies and highlights the relative oversight of Carboniferous actinopterygians: a specimen known for over 100 years from the most heavily sampled region of the Palaeozoic record is recognised as a new taxon. This oversight also contributes to phylogenetic uncertainty, as absence of distinct groups in phylogenetic analyses potentially obfuscates character evolution in the stem-actinopterygians seeding the crown and early, stem-members of extant clades. Despite the seemingly large scale of the problems facing understanding of early actinopterygian evolution, the means of addressing them is clear: taxonomic revision of key genera; expansion of phylogenetic datasets; increased sampling of underrepresented regions; and focus on localised diversity patterns
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