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Solar Thermal Fuels for Automotive Applications
No full textSolar thermal fuels are an emerging class of materials containing photochromic molecules (such as azobenzene) capable of harvesting, storing, and releasing solar energy. This thesis contains an investigation into the solar energy storage properties of azobenzene-based polymers for automotive application. The synthesis of azobenzene containing monomers and polymers, as well as the characterisation of the energy storage and release, thermal and optical properties is presented. The design and development of the polymer structure is discussed along with the method for creating polymer films. The films are used to evaluate the performance of the polymers as STF materials in the solid-state and demonstrate their viability for use under “real-world” conditions. It was found that the energy density of the polymer system was limited by the population of the cis isomer at the photostationary state. This arises due to the overlap of absorption bands for the trans and cis isomers and presents an intrinsic limitation on the energy density of the system. It was found that introducing an alkoxy group between the azobenzene moiety and the ester group led to a change in the electronics of the system resulting in changes to the absorption properties and in turn a higher photostationary state. This then corresponded to a significantly increased energy density. The presence of the alkoxy group also changed the physical properties of the polymer, most notably a decrease in the glass transition temperature, Tg. A decrease in the Tg can indicate an increase in the limited free volume of the system, increasing the photostationary state and rate of photoisomerisation. Consequential in the solid-state, thin films of this material reach photostationary states comparable to that observed in solution. This investigation highlights the importance of understanding the structure-property relationships in STFs, thereby providing a direction for optimisation for real-world energy storage applications
The Liability of Newness Revisited : Joiner Equity as an Early-Stage Advantage
No full textThis chapter introduces ‘joiner equity’, a novel construct describing the latitude granted by early-stage hires (or ‘joiners’) to start-up founders, such as tolerance of founder idiosyncrasy, role ambiguity and process immaturity, that would be far less acceptable in more mature organisations. This chapter theorises that joiner equity arises from the interplay of team psychology, efficacy beliefs and founder constraints in the context of new venture creation and the birth of organisations. Drawing on Stinchcombe’s (1965) liability of newness, it argues that the very conditions that make start-ups fragile, like thin routines, resource scarcity and improvisational governance, also generate a unique motivational climate. Joiners are attracted by the identity work of building something from scratch (Aldrich & Ruef, 2006; Gartner, 1985), the perceived growth trajectory, and proximity to decision-making, which together cultivate heightened self- and collective-efficacy (Bandura, 1997; Gully et al., 2002) and a psychological safety sufficient for risk acceptance despite structural deficits (Edmondson, 1999). Mechanistically, joiner equity is enabled by (1) bricolage under resource constraints (Baker & Nelson, 2005), which legitimises experimentation and reframes mistakes as learning; (2) effectual logic (Sarasvathy, 2001), which normalises iterative commitments and role boundary fluidity; and (3) nascent venture identity formation, whereby joiners internalise the venture’s narrative and view founder fallibility as part of a collective struggle (Aldrich & Ruef, 2006). The chapter proposes a dynamic model in which joiner equity is highest during start-up and early formation, amplifying team potency and problem-focused coping, and declines as ventures professionalise, with the shift to formal structures, role specialisation and compliance protocols narrowing discretion, reducing identity salience and perceived impact, often precipitating disenchantment and attrition among original joiners (Davidsson & Honig, 2003; Edmondson, 1999). Empirically, it outlines a mixed-method approach combining longitudinal team surveys (efficacy, psychological safety, role clarity), founder constraint diagnostics (resource availability, governance maturity), and retention outcomes across growth phases. The chapter anticipates curvilinear effects: joiner equity positively moderates performance during early growth but becomes maladaptive, as organisations professionalise, producing co-ordination losses, demotivation and burnout. The chapter contributes to literature on team psychology by specifying phase-contingent tolerance norms, to entrepreneurship theory by integrating effectuation and bricolage into the social psychology of venture teams, and to organisational birth research by illuminating how early social contracts evolve (and unravel) across scaling thresholds
Embodied Echoes : A Qualitative Exploration into Body Psychotherapy and Trauma
No full textThis thesis comprises three chapters, a systematic literature review, an empirical study and a critical appraisal, all in relation to body psychotherapy for recovery from psychological trauma (henceforth trauma). Chapter one is a scoping study of 24 peerreviewed papers, exploring the psychotherapeutic support options for people with trauma. The review illuminates that trauma can be held somatically within the body and how, by weaving the somatic dimension with the cognitive and emotional ones, body psychotherapy can promote body awareness, grounding and stability within trauma survivors. Chapter two employed a combination of Interpretative Phenomenological Analysis (IPA) and body mapping to explore the lived experiences of body psychotherapy among seven survivors of childhood trauma, as well as how they made sense of these experiences in the context of their recovery. Findings highlight that trauma recovery is often marked by periods of progression and regression. Participants reflected on how body psychotherapy provided a sense of validation for the inner (traumatised) child, often being the first treatment experienced which addressed the physical manifestations of trauma. Relief and progress within recovery were felt following the release of the somatic energy built up within the body, leading to improvements in mind-body relationships. Clinical and research implications include the consideration of body psychotherapy or body techniques within trauma treatment guidelines, cascading into further opportunities for training and service provision, and the applicability of BM as a methodology for both non-verbal data collection within research, and integration within assessments, formulations, and treatments. The thesis concludes with chapter three, a critical appraisal of chapters one and two as well as an honest reflection of the process and learnings involved with conducting the thesis project. Discussions surrounding the limitations and strengths of the empirical study and an evaluation of personal learning, are included
Understanding high functioning in people with a diagnosis of bipolar disorder
No full textBackground: Although there is evidence to suggest that some people with BD may be functioning successfully, previous literature has predominantly focused on impairment. Consequently, there is limited understanding of ‘high functioning’ in BD, including related factors and how it is experienced by those with a diagnosis. The Cognitive Behavioural (CBT) model offers a holistic approach to understanding onset and maintenance of BD, and consideration of the same range of factors may be able to increase understanding of how people function alongside their experiences. Aims: This PhD project aimed to increase understanding about people who are functioning at a high level alongside their BD diagnosis. Additionally, it aimed to identify predictors of functional level over time, and whether level of functioning influences attendance at group treatment programmes. Finally, this PhD aimed to recognise the subjective experiences of high functioning in people with a diagnosis who perceived themselves to be functioning at a high level. Methods:. A systematic review explored the BD literature for commonly used measured of social and occupational functioning. Pooled descriptive statistics from studies using these measures revealed population norms for functioning in BD. Multilevel linear modelling analyses were used to determine clinical and demographic predictors of functioning over time in a large BD sample, originally collected for a randomised controlled trial of psychoeducation versus peer support. A linear regression and moderation analysis, conducted using the same dataset, investigated whether functioning predicted level of attendance at psychoeducation or peer support groups in people with BD, and whether functioning level moderated the relationship between clinical and/or demographic variables and attendance at the groups. Finally, 20 self-defined high functioning individuals with a BD diagnosis were recruited for a qualitative interview study. Interviews and subsequent thematic analyses focused on participants’ experiences of functioning alongside their mood experiences, including how they defined their high functioning as well what they felt had contributed to it. Results: Pooled analyses of descriptive data extracted from studies using commonly used measures of functioning revealed that around 16% of individuals with a BD diagnosis can be expected to function at a high level. Multilevel linear modelling analyses revealed that increases in level of depression resulted in functional decline, however increases in mania only resulted in decline following an increase above the overall sample mean. People with a higher or postgraduate level of education were more likely to have higher and stable functioning over time, compared to those with lower education levels who were seen to decline. Those who were in employment were also seen to retain their functioning over time compared to those who were retired or unemployed. Linear regression analyses found that level of functioning did not predict level of attendance at psychoeducation or peer support groups, however it moderated the relationship between employment status and group attendance. Those who were low functioning were equally likely to attend the groups if they were employed or unemployed, however those with higher functioning were more likely to attend if they were unemployed. Finally, four key themes were identified through a thematic analysis which revealed that the way in which people defined their high functioning and pre-existing foundations for high functioning influenced strategies used by participants to support their functioning, and over time all of these developed and changed as a result of their experiences. Conclusions: There is a wide variability in the level of functioning of people with a diagnosis of BD, with a significant proportion functioning at a high level. In line with the CBT model, a variety of factors are related to functional level and the experience of ‘high functioning’ in BD. Mood changes and sociodemographic factors such as education level and employment status influence functional trajectory over time. However, functioning moderates the relationship between employment status and level of attendance at group treatment. This thesis contributes to current understanding of high functioning in people with a diagnosis of BD, and how this is experienced by those who are living the life they want to live alongside their mood experiences. Further research and clinical implications are discussed
Development towards Improved Respiratory Protective Equipment to resolve problems with industry standard following the COVID-19 pandemic
No full textThere are various environmental, ergonomic, and social issues surrounding currently used respiratory protective equipment (RPE). Most medical grade respirators are currently single use and are either incinerated releasing CO2 into the atmosphere or end up in landfill taking approximately 450 years to degrade. Additionally, many healthcare workers have reported pressure induced discomfort on the nose and cheeks due to donning RPE for prolonged periods, whilst some struggle to find a respirator which fits their face and have to rely on heavy and expensive powered air purifying respirators. Current RPE also acts as a physical barrier obstructing non-verbal communication. This research considered methods to address the identified issues using a combination of reverse engineering, additive manufacturing, and material science. A LiDAR scanner was used to assess the facial topology of the user. This information was then used to generate a computerised three-dimensional (3D) model of a respirator which is complementary to the user’s facial topology. An extensive literature review spotlighted potential biopolymer materials which show suitable characteristics for use in creating a respirator body that is both transparent and fully degradable under domestic composting conditions. Protocols for testing the transparent materials for their suitability were drawn up and testing of some of the materials and protocols were carried out
Approaches to produce defined electrically conducting polymer structures in 2D
No full textElectroceutical therapeutic devices which act as nerve interfaces have the potential to provide non-/minimally invasive treatments for a range of medical conditions. Examples of clinically translated devices employing electronics include cardiac pacemakers, electrodes for deep brain stimulation, bionic eyes and ears, and implantable pumps or controlled drug delivery. The success of such implanted materials/devices requires biocompatibility (i.e., no/minimal inflammatory response), with the ability to interact with external technology through transistors and circuits. This thesis builds upon investigations of printing 3D structures via direct laser writing of conductive polymers, to enable research on conductive biomaterials for various applications. The interdisciplinary project employs approaches involving chemistry, engineering and physics, to facilitate the production and characterisation of conducting polymer-based structures which can be envisioned to having potential for various applications in the long term. This project has shown a number of potential different approaches to form 2D structures as a result of polymerisation techniques. The primary constraints to stable structure formation can be identified as the physical strength of thin film polymer substrates, associated with uniform distribution of a homogenous resist where absorption of initiator is required for subsequent polymerisation, and the effective wavelength for the photoinitiator associated to photopolymerisation techniques. The direct polymerisation techniques of solution-phase and electropolymerisation contrast with the indirect photopolymerisation technique in terms of the potential for nano scale feature for bio-electronics from photolithography methods
Gift, Space, and Return : The Body in African Literatures on Migration and Sex Work
No full textThis thesis asks two principal questions. First, what insights could a gift approach to criticism bring to bear on African feminisms and feminist literary theory? Second, in what ways does gift-giving undergird contemporary African fiction on migration and prostitution? Both questions interrogate the need for alternative ways of engaging postcolonial (African) literatures in the age of global mobility. The argument is structured in four chapters in which questions about the relationships between gender and economies of exchange, space and subjectivity, commodifying bodies and the gift economy, and finally remittances and returns are engaged. First, I focus on the oikos as an arena where the female body circulates as the given, the giver and as resistant to the gift culture. The chapter also offers an alternative gift approach relevant to re-tooling African feminist theories through the concept of Nwanyịbuife. Second, I explore the link between identity and space politics within postcolonial cities of the South and the global cities of the North. Addressing spatial governance and practice, I also employ the phenomenologies of Franz Fanon, Emmanuel Levinas, and Maurice Merleau-Ponty to examine the complex gift of hospitality. Third, I scrutinize the connection between narrative, prostitution, and neoliberalism and in doing so, question/probe the link between capitalism and the gift. I interrogate how the gift drives the narrative structure of texts and is embedded in transactions on bodies. Finally, I investigate how the cargo myth of an earlier generation of African writers is being re-written as a contemporary narrative of returns and of contestations of power and belonging. Although references are made to other texts, when necessary, this work is based on five novels: Chika Unigwe’s On Black Sisters’ Street (2007) and Night Dancer (2011), Amma Darko’s Beyond the Horizon (1995), Abidemi Sanusi’s Eyo (2009) and Inongo vi Makomè’s Natives (2015)
Revised Methods Guide for Economic Evaluation Studies of Health Technologies in Portugal
Full text linkIntroduction: Economic evaluation supports public funding decisions about the use of health technologies within the Portuguese National Health System (NHS). The methods guide for economic evaluation in Portugal serves both companies preparing economic evaluation submissions and the independent commission appraising the evidence submitted. Methods: This article presents the revised methods guide for economic evaluation in Portugal. The revisions reflect advances in economic evaluation, updates to regulatory policies, and responses to the evolving economic context. The paper highlights the most significant changes to the guidance, comparing the new Portuguese guidelines to those from the United Kingdom and Canada. The discussion is framed around key comments received during public consultation. Results: The updated guidelines recommend cost-effectiveness analyses based on quality-adjusted life years and advocate for long-term modelling, a 4 percent discount rate, and a focus on NHS costs. New features include guidance on the identification and management of uncertainty within a dynamic appraisal process with regular contract negotiations (which can trigger reappraisals). The guide also covers how cost-effectiveness models, typically centrally developed, should be adapted to the Portuguese context. It highlights the key role of structured expert elicitation to address uncertainties in evidence, including those related to model adaptation. Conclusions: The revision was developed through stakeholder consultations and aligns with international best practices, offering more explicit and transparent methods to support health resource allocation decisions
Cross-Ownership and Endogenous R&D Risk in Cournot Triopoly
Full text linkWe examine how cross-ownership influences firms’ endogenous R&D risk-taking in a Cournot triopoly, where two "insider'' firms hold passive equity stakes in each other, and a third firm remains unaffiliated. Firms invest in stochastic R&D that lowers marginal costs and choose their risk level---measured by outcome variance---prior to quantity competition. Cross-ownership affects insiders through financial alignment and R&D spillovers, both intensifying with stronger equity links. Solving the two-stage game, we find that cross-ownership yields asymmetric, nonlinear impacts on innovation strategy. When spillover sensitivity is low, insiders undertake higher-risk R&D than the outsider; when sensitivity is high, this ranking may reverse. Increased cross-ownership always dampens the outsider’s R&D risk, while insiders’ risk rises with cross-holdings when spillovers are weak, but follows a U-shaped pattern when spillovers are strong. Enabling R&D collaboration does not affect the outsider, but can reduce insiders’ risk-taking when spillovers are substantial. However, when spillovers are exogenous and independent of equity ties, insiders’ risk increases monotonically with cross-ownership. These results identify information-sharing sensitivity as the key moderator of ownership networks’ innovation risk-taking, offering implications for competition and innovation policy