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Understanding the experience of ‘brain fog’ in coeliac disease: an interpretative phenomenological analysis
Get PDFThis thesis is submitted by Emily May Ahmed in partial fulfilment of the degree of Doctor of Clinical Psychology at the University of Birmingham. The thesis is comprised of three chapters. The first chapter is a meta-analysis which aims to provide a current prevalence estimate of depression in adults with coeliac disease, including evaluation of risk of bias factors. Additionally, it includes a brief secondary analysis, within the appendix, describing prevalence and relative risk estimates for other mental health disorders associated with coeliac disease. The second chapter is a qualitative empirical study which uses interpretative phenomenological analysis (IPA) methodology to explore the complex lived experiences of one of the lesser-known symptoms associated with coeliac disease – ‘brain fog’, in seven participants. Both the meta-analysis and empirical studies have clear clinical implications for the cognitive and psychological support that individuals with coeliac disease should be offered during and after diagnosis. Finally, the third chapter is comprised of two press release documents, which provides an accessible summary of the main findings of both the meta-analysis and the empirical research study
Effect of carbon allocation, land use change, and ozone pollution on global crop yields of major cereals: a modelling approach
Get PDFAgriculture is currently facing environmental challenges like climate change, air pollution, and land degradation, affecting agricultural productivity and threatening global food security. Besides, the increase in per capita food consumption among medium and high-income population, plus the expected increase in global population to around 9 billion by 2050, will lead to an unprecedented demand for food sustainably produced. To reach this aim, a holistic understanding of agroecosystems and their complexities is required. The Global Gridded Crop Models (GGCMs) have been developed to fullfill this requirement. Therefore, studies about the food systems require accurate crop models with explicit simulations of the productive processes and interactions with the environment.
This thesis aims to contribute to this broad effort to improve the performance of GGCMs by improving the representations of crop growth, stress response and yield with the Lund-Postdam-Jena General Ecosystem Simulator (LPJ-GUESS) model. The improvement focused on three aspects: (1) carbon assimilation and allocation processes, (2) the impact of past land cover change, and (3) the effect of ground-level O3 pollution on crop yields. The thesis evaluated how these factors affect simulated crop production and how the model can assess crop production under different environmental and management conditions at different spatial and temporal scales. Each of the three aspects also represents different types of uncertainty that the model has to address and are finally reflected in the model outputs, such as parameter uncertainty, input uncertainty and structural uncertainty.
LPJ-GUESS was improved, enhancing its capability to replicate yields, crop productivity processes, and the harmful effects on yield and harvest index simulated by the ozone module. These improvements have significant implications for developing more comprehensive and precise crop simulations that account for the complex interactions between crop production, environmental and management factors, and ozone. These advancements contribute to potentially more accurate global and large-scale yield simulations to better understand the impacts of climate change and terrestrial biogeochemical cycles on food production.
Overall, this thesis represents an improvement in the representation of productive crop processes and will increase the consistency of results in strategic research performed with LPJ-GUESS on the global food system. This is critical for researchers and policymakers to meet the current challenges of agriculture in feeding an increasing population in an environmentally and socially sustainable way
The episodic nature of consciousness: an investigation using rapid serial visual presentation
Get PDFWhat is consciousness for? Which cognitive functions can only be carried out with consciousness? Although much empirical work has explored these questions there is still not a definitive answer. In this thesis, we review how the evidence obtained with the Rapid Serial Visual Presentation(RSVP) paradigm could shed light on this issue. A key finding is the low recognition performance for RSVP stimuli that contrasts with the excellent performance in detection and identification tasks. This is suggestive of mechanisms that are highly efficient in the absence of conscious reports. Based on this effect and some of the theoretical ideas accounting for key RSVP effects we hypothesize that one cognitive mechanism that can only be carried out with consciousness is episodic encoding.
The thesis presents a series of experiment testing this hypothesis. Classic episodic memory effects are explored in the context of RSVP experiments. We address the repetition effect, the expected improvement in memory consolidation as items are repeated. Recency effects are investigated in the contexts of recognition and free-recall tasks. Proactive interference and list-length effect are also addressed using RSVP stimuli. Finally, we tested the reportability of task-irrelevant items.
Our main aim is to provide a comprehensive picture of the episodic memory effects that can be observed in RSVP. The results show that many of our findings are consistent with the view that most of the stimuli presented in RSVP sequences are not episodically encoded. This challenges the possibility of unconscious episodic encoding and agrees with our main hypothesis. These findings are discussed in the context of a theoretical proposal about the function of consciousness. The Tokenized Percept Hypothesis suggests that the unconscious activation of categorical or featural information might be enough for processes, such as detection or identification. While the acquisition of episodic properties necessitates conscious processing
Iran’s Construction Jihad through the Lens of Ideology, 1965-89
Get PDFWhile Iran’s Construction Jihad may no longer exist (having been absorbed into the Ministry of Agriculture in 2001), this institution – and the myriad of non-state and state-adjacent organisations it spawned – is perhaps the most fundamental manifestation of the social and economic identity of the Islamic Republic; a product of long-run factors dating back to opposition to the Pahlavi monarchy in the 1960s and the assimilation of leftist currents into a new Islamic radicalism wherein religion was viewed as a catalyst for radical social transformation.
This study aims to answer the question of how these conditions influenced and were influenced by the movement of Ayatollah Ruhollah Khomeini and how this intersection of intellectual currents led to the creation of Construction Jihad; the largest civic mobilisation of the Iranian people in modern history
Bimanual coordination and mirror visual feedback: implications for mirror therapy
Get PDFMost movements in daily life are performed with both hands. Both hands may do the same movement at the same time, or they may play different roles in demonstrating bimanual coordination to achieve the task. Stroke patients show abnormal bimanual coordination due to motor impairment. Traditionally, strategies of practising unimanual tasks with the impaired limb of stroke patients have been adopted to improve motor impairment. However, training with both hands simultaneously has been proposed as a more effective training strategy. Simultaneous symmetrical movement of both hands can benefit from an interlimb coupling effect, in which the movement of one hand impacts the movement of the other. In other words, bimanual training for stroke patients may improve movement deficits in the affected limb and help restore bimanual coordination. A mirror has been suggested as a device that may enhance the effect of bilateral training.
During mirror therapy, a mirror is positioned perpendicularly between both hands by placing the affected limb behind the mirror. Patients are instructed to move the unseen affected limb as much as possible while watching the movement of the unaffected limb reflected in the mirror. This promising intervention improves motor impairment and motor function in hemiparetic stroke patients. However, procedures used in multiple clinical studies and in practice vary considerably, and the underlying mechanism(s) that underpin mirror therapy are not known. Since the main purpose of mirror therapy is to improve the motor function of the unseen affected hand, this thesis aimed to contribute to our understanding of mirror therapy by examining the movement of the unseen hand that occurs during mirror visual feedback.
This thesis reports experiments that carefully examined bimanual movements for both unimpaired individuals and hemiparetic stroke patients under mirror visual feedback conditions. In the initial experiments (Chapter 2), the marked positional drift of the unseen limb (the limb behind the mirror) was highlighted when unimpaired individuals made continuous bimanual circle-drawing movements with mirror visual feedback. It became apparent that one might be able to examine an individual’s ownership and agency over the illusory limb from moment to moment by identifying whether the movements of the unseen limb were modified in response to visual feedback created by the seen limb. A subsequent experiment and novel analytical approach in Chapter 3 addressed this issue. Chapter 4 applied the knowledge and techniques learned from the previous chapters in examining bimanual movements in a small number of stroke patients. Recent research suggests specific parameters (e.g., using a large mirror, not using objects) that may contribute to the optimal effectiveness of mirror therapy for stroke patients. In the final experimental chapter, the impact of modifying these parameters on the illusory limb as indicated by subjective ratings was explored in unimpaired participants. A comprehensive summary of the experiments and a general discussion of theoretical and clinical implications and future directions are presented in Chapter 6
Thesis examining the accuracy of witness statements for real world criminal events
Get PDFEyewitness testimony is paramount to the solving of crimes by giving police forensically relevant evidence to apprehend suspects. However, eyewitness memory errors are also a leading cause of wrongful convictions (Innocence Project, 2020) which points to the importance of gaining accurate memory information from witnesses. Accuracy can be affected by both the witness being mistaken in their recollection or actively being dishonest. This thesis examines how the accuracy of memory reporting can be affected and discusses theory explaining memory reporting. This is achieved through examining the current field literature on memory reporting in a systematic literature review (Chapter Two). Next, a secondary data analysis on real world crimes examines the potential mechanisms that may underlie memory reporting in the field to enhance accuracy (Chapter Three). A psychometric critique of Statement Validity Analysis, with particular focus on the Criteria-Based Content Analysis component of this tool, is next discussed, which attempts to determine the credibility of witness statements (Chapter Four). Finally, the conclusions and the theoretical and practical implications of the thesis are discussed in Chapter Five. The thesis identifies future research areas needed to better understand memory reporting in the field and the possible theoretical mechanisms underlying witness memory reporting. It also suggests implications for practice, including for UK police interviewing practice, to improve the accuracy and completeness of witness statements. Ultimately, such implications should improve the accuracy of testimony, reduce wrongful convictions, and ensure that witnesses are not underestimated
Being in the band: exploring agency and structure in popular music
Get PDFBeing in the Band: Exploring Agency and Structure in Popular Music is a practice-led, phenomenological auto-ethnomusicology that investigates the musical and social dynamics of a grassroots rock band's quest for recognition and its complex interactions with the music industry. Through a series of band histories, this research examines Kerb’s setbacks and resilience after failing to secure a major record deal. The lived experience of making music is a critical feature of this phenomenological ethnomusicology. It combines an introspective narrative with thematic analysis to reveal how a rock band operates at a local level, constructs its sound, songs and identity, and navigates the interplay of personal agency within music industry constraints. The theoretical framework draws on Edward Casey’s phenomenology of remembering and imagining, which is leveraged to reveal how musicians construct meaning through their creative practices, interactions with technology, and responses to industry pressures. Kerb’s journey is traced from the edges of the Bristol music scene of the early to mid-2000s, confronting industry setbacks such as record label rejections and criticisms of the band's music and style. The band ventured to Sweden, funded by an independent record label, where they encountered the highly professionalised recording and production practices of Swedish producers. Ultimately, this study argues that first-hand, self-reflexive accounts are essential for understanding how musicians navigate their creative endeavours amid socio-economic and cultural forces. It offers a methodological contribution by demonstrating how phenomenological auto-ethnomusicology can illuminate the complex interplay between individual aspirations, artistic identity, and industry dynamics
Exploring epistemic injustice amongst non-clinical and clinical groups with unusual experiences
Get PDFCurrent literature on the philosophical concept of epistemic injustice, the notion that marginalised individuals are dismissed as credible in their capacity as a knower, suggests that this occurs within healthcare settings, perpetrated against those with a diagnosis surrounding poor mental health. However, much of the literature in this field is theoretical, with limited empirical research on this concept in relation to mental health. Whilst the case has been made for why those with psychosis may be likely to face epistemic injustice i.e. due to their perceived identity as a mentally ill patient and subsequent lack of credibility based on unusual experiences e.g. delusions, this has yet to be explored empirically. The present thesis aims to bridge this gap by exploring incidences of epistemic injustice amongst those with unusual experiences and those with a diagnosis of a schizophrenia spectrum disorder, in order to understand any factors between the groups that may contribute to this injustice.
Firstly, to add to the theoretical literature reviewed, the thesis examines whether occurrences of epistemic injustice exists across the relevant qualitative literature through the use of a meta-ethnography. In order to operationalise the philosophical concept of epistemic injustice, the thesis then utilises an interpretative phenomenological approach to explore frameworks of understanding and meaning-making processes in people with unusual experiences, but without a medical diagnosis (non-clinical group). Relationships with others pre- and post-the experience are also investigated. Following this, the same line of exploration is then repeated with individuals who have been diagnosed with a schizophrenia spectrum disorder (clinical group). Finally, the thesis uses a multiperspectival approach to compare the findings of the non-clinical and clinical groups, identifying conceptual overlaps or conflicts of perspectives between group experiential themes. Similarities and differences regarding the sense-making process as well as perceived treatment of others were examined between participants, in an effort to bring to light any incidences of hermeneutical injustice and testimonial injustice.
The analyses highlight hermeneutical injustices occur within the clinical group through poor timeliness and information-sharing surrounding the diagnosis, as well as dismissal of religious and cultural interpretations. In addition, testimonial injustices were also understood to occur through perceived changes in identity and subsequent lack of credibility afforded to clinical participants, leading to dismissal of testimony. The present thesis offers empirical support for the occurrence of epistemic injustice amongst individuals with psychosis in comparison to undiagnosed individuals with unusual experiences, suggesting that the injustice occurs in relation to diagnosis and perceived identity
A study to determine the validity and accuracy of a low cost, widely accessible 3d facial scanner compared to an established sterephotogrammetry based system
Get PDFABSTRACT
AIMS
The aims of the in vitro study were to determine the validity and accuracy of two Bellus3D devices - Bellus3D Face Camera Pro (Android device) and Bellus3D and iPhone 12 (Apple device), and two commercial 3D facial imaging systems - 3dMD and Di4D SNAP. The aims of the in vivo study were to determine the validity and accuracy of Bellus3D Face Camera Pro (Android device) compared to Di4D SNAP whilst
capturing the face at rest and at maximum smile.
MATERIALS AND METHODS
For the in vitro study a plastic mannequin head was pre-marked with 35 facial landmarks and the 3D coordinates of each of the landmarks was found using a coordinate measuring machine (CMM). This produced the gold standard 3D configuration. The head was also scanned using four three-dimensional imaging systems i.e., Bellus3D Face Camera Pro (Android), Bellus3D Application (app) and iPhone 12, 3dMD and Di4D SNAP. For each device the image was digitised on-screen. The 3D landmarks configuration for each device was compared to the gold standard
CMM data following partial Procrustes superimposition. The Euclidean distance between the landmark pairs was measured as well as mean absolute difference in the x, y and z-directions. For the in vivo study 21 landmarks were placed directly on the faces of 30 volunteers
meeting the inclusion criteria. Participants rehearsed rest position and maximum smile. For each participant images were captured at rest and maximum smile, using the Bellus3D Face Camera Pro and Di4D system. The images were digitised and both the 3D landmark configurations at rest were aligned using a partial Procrustes superimposition, this was repeated for both 3D landmark configurations at maximum
smile. The Euclidean distance and the mean absolute difference in the x, y and z direction between each landmark pair identified, a threshold of 2.0mm difference was set as being clinically significant different. Systematic and random error was assessed. Repeatability of rest position was also assessed.
RESULTS
For the in vitro study a two-sample Students t-test showed the mean difference in Euclidean distance (0.9 ± 1.4mm) between the Bellus3D devices and the commercial systems was statistically significant (p = 0.001) with a 95% confidence interval for the
difference of -1.4mm to -0.4mm). For the in vivo study, images taken by Bellus3D Face Camera Pro and Di4D at rest,
showed that 18 of 21 extracted landmark pairs had a mean Euclidean distance of less than 2.0mm. Three landmark pairs; right and left gonion and menton were outside of the clinical level of acceptability (>2.0mm). The smallest differences were seen in
landmarks located close to the midline of the face. For maximum smile, an additional 4 landmark pairs showed a mean Euclidean distance of greater than 2.0mm. These were right and left exocanthion and right and left cheilion.
CONCLUSIONS
The difference in accuracy and precision between the systems is most evident in the lateral and inferior landmarks because of the centralised camera location of the Bellus3D Face Camera Pro system and the need for subject rotation. Further reduction in accuracy was observed in maximum smile as the longer scanning time of the Bellus3D system captured involuntary changes in micro expression. Bellus3D Face
Camera Pro is suitable for clinical application if limited to areas adjacent to the midline in rest position. Bellus3D Face Camera Pro is not suitable for clinical use where investigation of lateral and inferior areas of the face is required, nor for transverse smile investigation
In vitro simulation of the human proximal colon to advance biopharmaceutics modelling
Get PDFThe Dynamic Colon Model (DCM) is an advanced in vitro model of the human proximal colon. This thesis takes an existing DCM through design, development and validation work to full application as an advanced biopharmaceutical dissolution apparatus. The model was improved in terms of robustness, longevity and industry-integratability. The number of motility patterns until failure was increased from 14, 400.
Magnetic resonance imaging (MRI) showed that the DCM mimicked wall motion, luminal flow patterns and velocities of the contents of the human proximal colon. The segmented architecture and peristaltic activity of the DCM generated flow profiles that were distinct from compendial dissolution apparatuses. Different motility patterns and media viscosities were shown to be classifiable by the degree of mixing-related motion
using a new MR tagging method. Furthermore, flow studies were used to inform the design of a digital twin that robustly replicated flow patterns in the DCM under different physiological conditions (media viscosity, volume, and peristaltic wave speed).
Five biorelevant motility patterns extracted from in vivo data were applied to the DCM which significantly affected theophylline release from a controlled release tablet. The concentration profiles of theophylline were markedly localized when measured at different segments of the DCM tube, highlighting the importance of a segmented lumen in intestine models and in generating spatial information to support simple temporal dissolution profiles.
It is recommended that viscosity and shear rates are considered when designing future dissolution test methodologies for hydrophilic matrix-based controlled-release formulations. Mean wall shear rates were strongly time and viscosity dependent although peaks were comparable to previously published estimates of the USPII operated at 25 and 50 rpm. The shear stresses invoked by the unstimulated, healthy adult human colon may be lower than those in the USP II at 25 rpm and thus insufficient to achieve total release of a therapeutic compound from a dosage form. When operated under stimulated conditions, measured drug release in the DCM was between that measured at 25 and 50 rpm in the USP II.
Ultimately, an in silico physiologically-based biopharmaceutic (PBB) model was developed for theophylline in Gastroplus®. To predict theophylline pharmacokinetics from a controlled release tablet formulation, Uniphyllin Continus®, dissolution profiles from the DCM were integrated as global mean data and regional release profiles. The latter used spatiotemporal data collected in the DCM to model drug dissolution and distribution throughout the continuous caecum-ascending colon lumen. Predicted absorption rate was inherently sensitive to hydrodynamics (using the USP II apparatus as a control). Motility patterns which caused drug to accumulate in the caecum resulted in a lower predicted absorption rate than those which performed better at homogenising the lumen, which may have consequences for formulation performance in subjects with impaired motility. Recommendations are made to further compartmentalise the colon in PBB modelling platforms to improve prediction performance for controlled release formulations
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