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Short-term solar PV forecasting in microgrids using cloud top temperature and vision transformer based models
Full text linkExploring Diversity in Apprenticeships: Key Actors, Organisational Practices and the Lived Experiences of Racially Minoritised Apprentices in England
No full textRacially minoritised young people are underrepresented in apprenticeships in England despite government reforms, including a 2015 agenda to increase the representation of racially minoritised youth in apprenticeships by 20% by 2020. Research exploring apprenticeships and racial diversity is scarce within diversity and wider management and organisational studies. This thesis explores the underrepresentation of racially minoritised young people in apprenticeships in England. It seeks to understand how race intersects with other social identities and influences the apprenticeship experience. Adopting a multi-layered approach, this thesis examines racial underrepresentation in apprenticeships by juxtaposing three levels: state policy, employers’ policies and practices, and the individual experiences of racially minoritised apprentices. The study employed an inductive qualitative research design, aligning with interpretivism and influenced by critical theory. A total of 53 interviews were carried out with 58 participants across three sample groups: 17 key informants (individuals involved in apprenticeship policy and implementation), 11 apprenticeship leads from 10 employer organisations, and 30 racially minoritised apprentices. Interviews were analysed using thematic analysis and were supplemented with secondary data from government policy documents. The findings reveal that apprenticeship diversity discourse prioritises socio-economic status/social mobility, with race being sidelined. This impacts how employers approach the diversity agenda of apprenticeships, with very few organisations adopting bespoke diversity strategies and practices to address racial inequalities in apprenticeships within their organisations. Where they do, they rely on positive action mechanisms in line with liberal equal opportunities approaches in the UK. Many, however, default to rhetorics of race-neutrality and ‘hiring the best’ in relation to efforts to improve racial diversity in apprenticeships. For racially minoritised young people, financial considerations (shaped by parental socio-economic status and ethnic/cultural expectations) influenced their decision to embark on an apprenticeship programme. In addition, through informal interactions at work, they experienced marginalisation based on race, intersecting with gender, age and faith which shaped their experiences of the workplace as apprentices. By situating apprenticeships within critical diversity management scholarship and broader management and organisation studies, this thesis enhances our understanding of how diversity discourse and 6 practices are framed in the apprenticeship context and how key actors within and outside employer organisations shape this. Furthermore, the thesis illuminates how racially minoritised young people, at a particular stage of their working lives, experience marginalisation. It offers a new, empirically grounded perspective that can inform how policymakers and employers’ approach and implement apprenticeship programmes in more racially inclusive ways
Native linguistic adaptation among mobile speakers of French
No full textThis thesis examines the impact of long-term second dialect (D2) exposure due to geographical mobility on the native phonological system. While much research has explored the effects of D2 exposure on speech production, few studies have explored changes in speech perception due to D2 exposure. This study addresses both of these aspects of second dialect acquisition by considering French speakers having moved in adulthood between France and Quebec. To examine how D2 exposure and native dialect shape individual linguistic change, data were collected from four groups of participants: i) non-mobile speakers of Hexagonal French (HF; French of France), ii) non-mobile speakers of Quebec French (QF), iii) mobile speakers of HF residing in Quebec, and iv) mobile speakers of QF residing in France. Participants completed a battery of experimental tasks assessing their production and perception of phonetic features differing between QF and HF. Extralinguistic measures predicted to moderate the effect of D2 exposure on linguistic change were also collected. Results from a sentence reading task align with previous studies showing changes in production to be subtle and to affect some linguistic features but not others. Regarding perceptual change, results from a phoneme categorization task and a speech-in-noise comprehension task jointly confirm that D2 exposure can lead to changes in the native perceptual system. However, the fact that the mobile HF participants showed greater perceptual adaptation than the mobile QF participants suggests that the extent of this change is constrained by the native phonology. Lastly, exploratory analyses of extralinguistic factors in linguistic change reveal that, while some factors can moderate the impact of D2 exposure on native linguistic change, the magnitude and direction of these effects vary across participant groups, tasks, and linguistic features. Overall, this research contributes to an understanding of how the native linguistic system can change across the lifespan
Circulating inflammatory proteins predict dementia risk, are linked to structural brain changes and modifiable risk factors.
Full text linkINTRODUCTION: Systemic inflammation has been identified as a key factor in neurodegeneration but the value of circulating inflammatory proteins in dementia risk prediction and their causal role has not been elucidated. METHODS: We leveraged proteomic data from 43,685 UK Biobank participants to investigate associations between 728 Olink inflammatory proteins and incident dementia using Cox proportional-hazards (Cox-PH) models. We used Cox-PH with LASSO regularisation to calculate a sparse signature of inflammatory proteins (ProSig) predicting incident dementia. Linear regressions assessed the association between ProSig and individual proteins with brain image-derived phenotypes and Brain Age in participants with available neuroimaging data (n = 4,106). Formal mediation analyses investigated whether inflammatory proteins mediated associations between genetic and modifiable risk factors and dementia outcomes. Mendelian randomisation (MR) tested the causal relationship between inflammatory proteins and dementia outcomes. RESULTS: 218 inflammatory proteins were individually associated with incident dementia in Cox-PH models (pFDR < 0.05). A 20-protein signature significantly improved the prediction of incident dementia beyond known risk factors. TNFRSF11B, a protein linked to vascular damage, was associated with both incident dementia and reduced hippocampal volume. Two proteins, sFRP4 and MEPE, were linked to reduced Brain Age, with sFRP4 also being protective against dementia. Mediation analyses indicated that TNFRSF11B, APOE and C7 may partially mediate associations between modifiable risk factors and dementia. MR analyses suggested protective causal effects of TNFSF13 and IL17D. CONCLUSIONS: By triangulating evidence, this study shows that inflammatory proteins improve dementia risk prediction and play heterogeneous roles in dementia pathophysiology
From Sedentary Individuals to Highly Trained Athletes: A Comprehensive Cardiovascular Magnetic Resonance Imaging Study of Cardiac Volumetry, Function, and Strain.
No full textBACKGROUND: Physiological remodeling of the athlete's heart can resemble certain cardiomyopathies, underscoring the importance of robust reference standards. However, most cardiac magnetic resonance imaging (CMR) based studies focus on a narrow subset of adult athletes, providing limited insight into the broader spectrum of exercise-induced changes. Here, we aimed to characterize volumetric, functional, and strain-based adaptations across varying physical activity levels, age groups, and sexes and to establish reference ranges. METHODS: We enrolled 656 participants (13-35 years) in a cardiovascular screening program at our tertiary center (2009-2020). We excluded individuals with cardiac disease, risk factors, or abnormal screening findings. Participants were categorized as sedentary (≤3hours/week), recreational (4-6hours/week), or highly trained (>6hours/week) athletes. CMR was performed using 1.5T scanners to assess ventricular and atrial volumes, myocardial mass, ejection fractions, and feature-tracking strain. We derived 95% prediction intervals stratified by age, sex, and training volume. RESULTS: Of the 575 healthy subjects, 390 were highly trained athletes (22±6 years, 64% male, 19±7 training hours/week), 102 recreational athletes (23±6 years, 60% male, 4±1 training hours/week), and 83 sedentary individuals (26±4 years, 42% male, 1±1 training hours/week). Increasing weekly training hours were associated with larger ventricular volumes, higher myocardial mass, lower ejection fractions, and strain. Compared to sedentary individuals, highly trained athletes had significantly larger left and right ventricular volumes (LVEDVi estimate [95% CI]: 0.82 [0.52-1.12], p<0.001), higher myocardial mass (LVMI 0.59 [0.31-0.86], p<0.001), and increased left and right atrial volumes, even after adjusting for age, sex, and weekly training hours. We observed a non-uniform dose-response relationship across activity levels, with the most prominent cardiac adaptations occurring in highly trained athletes. Endurance athletes exhibited the most pronounced volumetric changes among the sport types. Finally, we derived stratified prediction intervals to provide CMR reference ranges in young, healthy individuals stratified by age, sex, general activity level, and weekly training hours. CONCLUSIONS: This work underscores the influence of age, sex, physical activity level, and type of sports on cardiac adaptation. We provide prediction interval-based CMR reference ranges of volumes, mass, ejection fraction, and strain to improve disease discrimination in athletes
Pandemic geographies of home: domestic thresholding in response to COVID-19
Full text linkWith the home at the forefront of political and public health responses to COVID-19, the thresholds between domestic space and the world beyond acquired a new significance in people’s everyday lives. Whilst pre-pandemic research stressed the porosity of domestic thresholds and the capacity of home to stretch beyond domestic space, ‘stay home’ directives and lockdown restrictions demarcated home as a place of containment, separation and immobility at the height of the pandemic. By analysing interviews conducted with adults in London and Liverpool and maps drawn by children and young people throughout the UK, this paper introduces the concept of ‘thresholding’ to address three key questions: how were domestic thresholds secured, crossed, and remade during the COVID-19 pandemic? How were people’s everyday lives in pandemic times mediated by internal and external domestic thresholding practices? What are the wider implications for understanding geographies of home during and beyond the pandemic? We argue that the enhanced significance of domestic thresholds in pandemic times was materialized and embodied through new, reworked, and more labour-intensive thresholding practices. We reveal not only the changing relational dynamics of homespaces during lockdown, but also how people’s everyday lives continued to be shaped in varied and uneven ways by the world beyond, as well as within, domestic space. The concept of thresholding reframes the relational spatialities of home by foregrounding the ways in which internal and external thresholds are understood and materialized through embodied practice
Transmission Strategies in Integrated Sensing and Communications
No full textTo alleviate spectrum congestion in the sixth generation (6G) network, integrated sensing and communications (ISAC) has been proposed to share the spectrum and hardware resources between dual functionalities. In this thesis, the transmission strategies in ISAC systems are investigated from the enabling aspects towards the emerging aspects. For the ISAC enabling aspects, a hybrid non-orthogonal multiple access (HNOMA) technology is proposed to deal with the dual functionality access challenges. The beamformer-based nonorthogonal multiple access (NOMA) and the cluster-based NOMA algorithms are proposed to minimize the transmission power. Then, a simultaneously transmit and reflect surface (STARS)-assisted ISAC framework is proposed to combat the blocked line-of-sight challenge. The block coordinate descent (BCD)-based integral matrix algorithm and BCD-based elementwise algorithm are proposed to jointly optimize the active and passive beamforming (BF) design. Numerical results demonstrated 1) the proposed HNOMA algorithms reduce the transmission power; 2) the proposed BCD algorithms achieve beampattern gain improvement over multiple sensing targets. For the ISAC emerging aspects, a ‘sensor-at-STARS’ near-field (NF) framework is proposed to adapt the spherical wavefront propagation challenge in 6G. A conditional optimal sensor interval and the penalty-based algorithms are proposed to balance the square position error bound (SPEB) and the deployment cost. Furthermore, a uniform circular antenna (UCA) framework is proposed to address the non-uniform NF propagation over different directions. The vector-based quadratic transformation (VQF) algorithms are proposed to improve the SPEB by the Rayleigh quotient decomposition. Numerical results validated 1) the fisher information matrix can be approximated as the diagonal matrix with trinity loss; 2) the proposed algorithms reduce at least 30% estimation error in SPEB accompanying the lowest deployment cost; 3) the UCA achieve 30% positioning precision improvement for the co-plane sensing target; 4) the proposed VQF algorithms elevate the 2.5% solution precision with only 1/Nt computation complexity than semidefinite relaxation algorithm