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Internal Governance Mechanisms and Financial Reporting Quality : Evidence from Alternative Banking Systems
Get PDFPh. D. Thesis.Anglo-American research has long documented the positive impact of effective corporate governance mechanisms in improving corporate financial reporting quality. However, examination of this causality across different bank types (e.g. conventional and Islamic banks) is still lacking. This thesis investigates the role of different internal governance mechanisms (i.e. boards of directors and audit committees) in enhancing the financial reporting quality in conventional and Islamic banks. It utilises the Islamic banking model operating on an extended governance structure (i.e. Shari’ah supervisory board) to gain new insights into the influence of bank institutional characteristics and additional monitoring mechanisms on managerial opportunism and on the information value of earnings. For a sample of listed conventional and Islamic banks from 16 countries, the results are twofold. First, the findings provide evidence that having a large and independent board of directors and audit committee is associated with reduced levels of earnings management for both conventional and Islamic banks. These findings demonstrate the absence of structural differences between the two bank types regarding the effectiveness of the traditional governance mechanisms in limiting opportunistic earnings management behaviour. Conditional on the bank type, the results show that the presence of an additional layer of governance through employing a large and financially qualified Shari’ah supervisory board, whose members serve on multiple boards, provides a significant deterrent against earnings management in Islamic banks. Second, the findings provide evidence for the role of effective boards of directors and audit committees in enhancing the information value of earnings. The results show that large and independent boards and audit committees are associated with more persistent earnings, predictable cash flows, and reliable loan loss provisions that are highly associated with future loan charge-offs. The findings of this thesis provide valuable insights for a better understanding of the role of traditional and additional monitoring mechanisms in promoting financial reporting quality in both banking types.Government of Bahrain, University of Bahrai
Interaction between cortical state, dopaminergic modulation, attention and decision making
Get PDFPh. D. ThesisCortical activity reveals spontaneous fluctuations that are not solely determined by external inputs, but reflect changes to the underlying excitability of neurons, referred to as cortical state. These fluctuations are partly linked to fluctuations in arousal, whereby they influence sensory processing as well as behavioural performance. During active versus inactive states, the cortex is more desynchronised and displays suppressed low-frequency and increased high-frequency activity, as well as lower correlations in population spiking activity. Selective attention facilitates the prioritisation of task-relevant sensory inputs over those which are irrelevant. When attention is directed towards the receptive field of the recorded neuronal population, firing rates increase and, interestingly, this area of the cortex desynchronises in a comparable manner to that observed during cortical state fluctuations. Because of these similarities, it has been suggested that cortical state and selective attention might rely on related underlying circuit mechanisms.
In this thesis, I investigated cortical state changes across different spatiotemporal scales and across species, using pupil diameter as an across-species proxy for neuromodulatory controlled central arousal state. In the first chapter, I describe how global, arousal-mediated state fluctuations influence specific behavioural and electro-encephalographic (EEG) signatures of perceptual decision-making in human subjects. Arousal strongly affects behaviour and task-related activity across the brain, including in visual, association, and motor cortex.
In the second chapter, I described how top down covert attention affects neuronal signatures of cortical state within sensory areas and their coordination between visual areas in Macaque monkeys. Using a Hidden Markov Model (HMM), I classified periods of vigorous (On) and faint (Off) population spiking activity. These periods were coordinated in a top-down manner across brain areas along the visual hierarchy during selective attention and this coordination was furthermore predictive of behavioural performance.
Finally, in the third study, I tested how the local effects of attention induced cortical state changes within a single area are influenced by iontophoretic administration of dopaminergic drugs. Dopamine strongly affects neural activity in parietal cortex, with specific modulations of activity related to attentional processing.
These results highlight the strong influences of cortical state and attention on neural activity and behaviour, as well as the crucial role of the interaction between these two functions. They furthermore shed light on the neural mechanisms that underlie cortical state fluctuations, top-down attention and perceptual decision making, from small scale modulations of single neuron firing rates, to the way activity within and across brain areas is coordinated and finally to the way they influence behavioural performanc
Terrae amissae: A comparative study of Southwest Germany and Transylvania in the mid-third century AD
Get PDFPh. D. Thesis.This thesis is an exercise in archaeological interpretation of the abandonment of frontier areas of the Roman Empire during the mid-third century AD. The regions of Southwest Germany and Transylvania are chosen due to four critical factors. Both are frontier zones beyond the traditional river boundaries of the Empire. They not only had a large military presence, but also urban and rural settlements, providing a diverse assemblage of sites to examine. Furthermore, both regions were ceded by Roman authority during this period. Consequently, this has led to circular argumentation in interpretation of the latest Roman phases of occupation. Similarities of these regions has warranted brief discussion in the past. However, this is the first study to exhaustively work through the data both in German and Romanian.
This period of history is crucial in the transition of the Roman World into Late Antiquity, but there is little that can be proven in the archaeological narrative. In general, there is a paucity of literary sources, yet these have led the narrative not only for these regions, but for the Empire as a whole. This thesis seeks to examine published material in a forensic manner, documenting evidence for activity and abandonment during the period, highlighting what is known and what is implied across multiple languages and academic traditions. Additionally, the period numismatic and epigraphic assemblages for each region are set against their respective general trends.
The result is a thorough assessment of the limits of our understanding of this crucial period based on the archaeological evidence as it exists rather than an interpretation of the archaeological material via the literary sources. The overarching aim is to highlight the historical and methodological pitfalls that have distorted discussion of both areas to show how further studies of this period might better utilize the physical evidence.DAAD, Institut für Vor- und Frühgeschichtliche und Provinzialrömische Archäologie at Ludwig-Maximilians-Universität, Munich
Design, manufacture, and applications of high mass resolution orbital trapping for secondary ion mass spectrometry
Get PDFPh. D. ThesisSecondary Ion Mass Spectrometry (SIMS) is a widely used analytical technique for
characterizing surface chemistry in numerous technical applications, including medical
implant surfaces, fault-finding in semi-conductors, proteomics, pharmaceutical
development, and in the field of astrobiology and the search for extra-terrestrial life.
The mass resolving power of modern time-of-flight SIMS (ToF-SIMS) instruments does not
exceed 12,000. This means that for some mass spectral peaks, a single molecular formula
cannot be definitively specified. This is particularly important for high mass molecules,
where there can be many possible peak attributions for a given nominal mass.
Orbital ion traps have been shown to achieve mass resolution in excess of 100,000,
without the need for the large and expensive superconducting magnets required in Fouriertransform
ion cyclotron resonance (FT-ICR) instruments. Therefore, an orbital ion trapping
mass analyser has been designed, fabricated, and coupled to the Ionoptika J105 SIMS.
Computational modelling has been developed to evaluate proposed designs and examine
the effects of manufacturing imperfections on the performance of the orbital ion trap.
A method of exciting a precise mass range of trapped ions has also been developed, using
a Stored Waveform Inverse Fourier Transform (SWIFT) technique. This allows fast, high
mass resolution analysis after a low-resolution spectrum has been gathered using the
time-of-flight analyser.
This thesis will cover the function and capabilities of the Ionoptika J105 SIMS, the need
for high mass resolution in SIMS, the mathematical background of electrostatic harmonic
ion traps, and the simulation, design, manufacture, and operation of the orbital trapping
mass analyser. This research allows mass spectra to be gathered with both high mass and
spatial resolution, an advancement with numerous potential applications, including labelfree
biological imaging and the unambiguous identification of biosignatures in astrobiology
Meiotic chromosome dynamics: a structural characterisation
Get PDFPh. D. ThesisMeiotic chromosomes are bound in architecturally enforced synapsis during the first meiotic division
by a proteinaceous megastructure known as the synaptonemal complex (SC). This molecular scaffold is
built between paired homologues, providing a unique three-dimensional environment in which to form
genetic crossovers, physical inter-homologue connections critical in ensuring equational segregation at
metaphase. The SC structure represents the hallmark of meiotic division, with a striking tripartite
appearance, conserved across evolution, in which chromosomally associated lateral elements are
connected to a midline central element via transversal filaments.
Such that the SC installs between correctly identified maternal-paternal pairs, a genome-wide, sequencebased,
homology search is facilitated by rapid chromosomal movements. Cytoskeletal forces power
these movements, transmitted through the nuclear envelope (NE) to the chromosome’s telomeric ends
via the LINC (Linker of Nucleoskeleton and Cytoskeleton). Importantly, NE recruitment and tethering
is mediated by the meiotic telomere complex, consisting of MAJIN, TERB1, and TERB2, without which
meiotic progression is stalled.
The works herein reveal the structural basis of synapsis in the human SC and chromosome tethering to
the nuclear envelope by the meiotic telomere complex. Specifically, I report a complete biophysical
characterisation of SYCP1, the transversal filament protein of the human SC, and present crystal
structures which represent mechanisms of its assembly within the SC mediated by sequences at both its
N-termini (which mediate midline, head-to-head, associations) and C-termini (which undergo pH
dependent, back-to-back assembly on the chromosome axis). Further, we solved the crystal structure of
the MAJIN-TERB2 complex and characterised its mode of DNA association providing key insights into
how NE tethering is achieved. Our findings are discussed within the context of the existing molecular
understanding of meiotic chromosome dynamics
A spatial-based programme approach to water supply development in Indonesia
Get PDFPhD ThesisWater provision is urgent in Indonesia. Currently, there are five water infrastructure systems programmed to improve the provision of water to users in Bandung City. These include a system for the south, two systems for the west, and two systems for the east of Metropolitan Bandung. Out of four phases, the first phase of the South System has been completed with four years of delay, while the following phases of the south, east, and west programmes are still being planned.
This research investigated the delay in completing the first phase of the South System, which was scheduled for completion in 2015 as one of the Millennium Development Goals. The research recognises that organisational structure (central, provincial, local (city/regency) governmental, and other stakeholders) and organisational processes both play a significant role in the programmes’ completion.
Consequently, this research developed a mixed-analytical approach from the disciplines of spatial planning and programme management, emerging from their respective literature, to create the concept of a “Spatial-Based Programme Approach”. This is a combined concept from both disciplines which draws on their respective concerns and strengths. It incorporates key aspects of spatial planning in integrating infrastructure components spatially, and key aspects of the programme approach in synergising related projects. Potentially, it may provide a new form of operation in the future development of water infrastructure programmes.
By using the abductive research process, I propose the Spatial-Based Programme Approach to address the synergy problems revealed by the research within the development of a regional water system in Indonesia. By considering the outcomes from an extensive literature review, intensive discussions with key informants in Bandung and Jakarta, and following this abductive research process, this research confirms that the Spatial-Based Programme Approach is a convincing management approach to the development of water supply in Indonesia.
Besides improving synergy, there may be certain other benefits for a programme in applying this approach, namely being more goal-oriented, adaptive and responsive to risks and changes, and promoting sustainable development. This research also recommends how to apply the Spatial-Based Programme Approach in the Indonesian context.Ministry of Public Works and Housing, Indonesia Central Government
Rapid detection of immunotoxicity and adverse reactions to new compounds using 3D skin equivalent models
Get PDFPh. D. ThesisSafety testing procedures and risk assessment analysis of newly developed chemicals are mandatory to attest them as non-toxic for human handling. The European Union implemented several regulations enforcing safety testing and has recently banned the use of animals for toxicology studies for human safety.
From in vitro cell-based assays to reconstructed human epidermis (RHE) models, there are several non-animal alternatives for toxicology studies to determine human safety. Cell-based assays are not accurate enough to predict the toxic potential of chemicals as they are a two-dimensional (2D) representation of skin cells. Three-dimensional (3D) RHE models are better, as they allow for differentiation of skin epidermal layers (i.e. stratum corneum). Commercially available RHE models are now the gold standard for toxicity studies for human safety and some of these have been validated by the Organization for Economic Cooperation and Development (OECD) for skin irritation and corrosion testing (two major categories of skin toxicity).
The aim of this study was to develop an open source 3D epidermal skin culture based on Poumay’s work. Using the Alvetex Strata scaffold, cell seeding was optimised using 1x106 keratinocytes for a 30 day culture period for best differentiation of the stratum corneum layer (confirmed by immunofluorescence staining of involucrin). Further optimization of vitamin C and calcium supplements did not seem to improve distribution of keratinocytes throughout the scaffold. Ultimately, the best results were achieved by the addition of a human-based collagen coat to the Alvetex Strata Scaffold, where development of stratum corneum was confirmed by collagen and involucrin staining. Moreover, development of the stratum basale layer was confirmed by cytokeratin 14 immunofluorescence.
Evaluation of the 3D epidermal skin culture was tested following OECD Testing Guideline (TG) 439 for skin irritation in 12 reference chemicals from the 20 reference chemicals list in TG 439. Results showed the 3D epidermal skin culture was able to distinguish non-irritant from irritant chemicals using 10 different keratinocyte donors. Comparative performance analysis with a monolayer (2D) keratinocyte culture, a commercial RHE model and a collagen-based RHE models were performed. Results showed similar outcomes between the different models, while the monolayer culture performed poorly in discriminating irritant from non-irritant chemicals. Overall, these results were indicative of the predicative capacity of the 3D epidermal skin culture for in vitro testing of skin irritation.
The second aim of this project was to use a skin explant assay, developed by Alcyomics, as a novel in vitro test for assessment of immunotoxicity caused by aggregation of monoclonal
antibodies (mAbs). mAbs are important therapeutics but their potential for aggregation has become a critical quality parameter that can turn into a potential health risk during the administration of mAb therapeutics to patients. While the extent of immunotoxicity in patient populations is uncertain, reports show that it can lead to immune responses via cell activation and cytokine release. Our results showed that aggregated mAbs caused adverse immune events by evidence of tissue damage, expression of cell death markers and overall increase of IFN-γ (pro-inflammatory cytokine). These results showed that the skin explant assay could be a promising tool for predicating immunotoxicity caused by mAb aggregation.
In conclusion, this study has provided further insight on the assessment of skin toxicity and immunotoxicity using in vitro skin assays.BIORAPI
Frailty in Tanzania: a longitudinal mixed methods study
Get PDFPh. D. ThesisBackground
Population ageing is occurring globally and sub-Saharan Africa has the most rapidly growing older population. Frailty in old age is likely to become of increasing importance therefore. Several biomedical models of frailty have been proposed, including the frailty phenotype which defines frailty as a syndrome of age-related physical changes meeting a standard criteria. An alternative model is the frailty index, which conceptualises frailty as the product of accumulating age-related “deficits”, these being diseases, disabilities, signs or symptoms.
Aims
The quantitative aspect of this study sought to operationalise both of these frailty models, comparing them with expert consensus, applied through the Comprehensive Geriatric Assessment. The aim was to investigate the prevalence characteristics and outcomes of frailty in rural Tanzania. The qualitative aspect of the study aimed to investigate how frailty is understood in the study’s setting, as well as the lived-experience of frailty from the perspectives of older people and their communities.
Methods
Quantitative methods included screening adults aged ≥60 years from five randomly selected villages in rural Hai District, Northern Tanzania. Survey questionnaires and anthropometric measurements were conducted, alongside comprehensive geriatric assessments on a frailty-weighted cohort. Qualitative methods involved semi-structured interviews and focus group discussions with a purposive sample of older people, their family members, and community representatives. Transcripts were transcribed, translated and analysed thematically.
Results
Results showed that frailty by biomedical models detected frailty, and replicated the expected epidemiological patterns. Six qualitative themes were developed that demonstrated frailty to be experienced and understood as either a natural conclusion to a long life, or an aberrant form of ageing due to a scarcity of resources and care.
Discussion
Findings were synthesised dialectically in order to arrive at a deeper understanding of frailty, its characteristics and outcomes in this rural African context
What supports teaching assistants' learning and development in primary schools?
Get PDFD. App. Ed. Psy. ThesisThere is increasing focus and mention of Teaching Assistants (TAs) in educational and governmental policies, initiatives and schemes in England. TAs have become synonymous with Statements of special educational needs and disability (SEND) / Education Health and Care Plans and are central to strategies for educating children and young people with such support. There is debate about their effectiveness and how / if they are prepared for their role in supporting children with additional and complex needs. In 2014, the Department for Education (DfE) set out to create professional standards for all TAs to coordinate their practice and professional development (PD) in England but this was not published by the government. The focus of this research relates TAs’ perspectives and processes involved in their professional learning.
A systematic review of literature revealed that limited attention has been given to TAs’ views about their learning, and how the wider context may impact their practice, learning and development. As such a meta-ethnographic review of current literature exploring TAs’ views about impact of PD is presented. From this, efficacy, relationships and identity were highlighted as prominent factors influenced by PD activities. Organisational context played a pivotal role in these three areas, highlighting an interplay between TA and environment. In the studies, there appeared to be a lack of in-depth understanding of what the TAs themselves thought supported their learning and practice.
The aim of the linked empirical research was to explore: “How do Teaching Assistants learn in the workplace?” The research used realist Grounded Theory (GT) to analyse interviews with four TAs working in a mainstream First School and to develop a model. The emergent model highlights that TAs learn and develop in an organisational context with a supportive leader and culture. However, positive relationships appear to be fundamental to their learning and development in primary settings. The research findings are placed within the context of existing research. Implications for schools, policy makers and Educational Psychologists (EPs) are discussed and thoughts for future directions are suggested.
A bridging chapter links the meta-ethnography to the empirical research. It explains my interest and motivations for carrying out this research and explores how my
assumptions, values and beliefs about the world and knowledge influenced the research process and knowledge produced
Comprehensive study of biocathode in Bio-electrochemical system (BES) for energy harvesting and CO2 conversion
Get PDFPhD ThesisThe focus of this thesis is studying the mixed community biocathode to solve the bottlenecks for the scale-up and commercialisation of Bio-electrochemical Systems (BESs).
First, the utilisation of aerobic iron-oxidising bacteria enriched from natural environment and Fe2+ in Microbial fuel cell (MFC) equipped with gas diffusion electrodes was studied as an efficient alternative to Pt-based catalysts for MFCs with unlimited oxygen diffusion. Controlling the system pH during continuous operational mode, MFCs produced maximum power density of 0.251 mW cm-2, compared to 0.134 mW cm-2 for MFCs equipped with Pt catalyst (0.5 mg cm-2 Pt on carbon paper) indicating advantages of fully microorganism catalysed system, and importance of operational parameters in such systems.
In microbial electrosynthesis (MES) converting CO2 to various organic compounds, optimisation of operational parameters, such as applied potential on the cathode, pH, and operational mode were investigated. The community analysis revealed different dominant communities on the electrode and in solution suggesting an electro-active biofilm was formed on the cathode. It also suggested the importance of cathodic potentials corresponding to sufficient energy provided for MES and inorganic carbon sources (CO2 and HCO3-) on biofilm formation and composition of bacterial community in biofilm responsible for MES, respectively. It was found that -1.0 V (Ag/AgCl) was required for MES, and CO2 was preferred inorganic carbon source for microorganisms for MES. Mechanisms of MES and chain elongation were studied. The hypothesis on hydrogen mediated electron transfer mechanism was confirmed from cyclic voltammetry showing a positive shift on hydrogen evolution onset potential with optimum conditions. The role of cathode on providing electrons was explored comparing the systems operated at open circuit potential (OCP) and applied potential. In addition, two different strategies of 1) impact of continuous operational mode and, 2) addition of external electron donors were investigated to promote chain elongation through acetate, triggering crucial parameters affecting production through MES.
Acetate concentration reached the maximum of 6.8 g L-1 over fed-batch mode with a production rate of 660 ppm day-1 (maximum columbic efficiency~69%), while the highest acetate production rate in this study was reached over continuous operational mode (803 ppm day-1, maximum columbic efficiency~90%). Over longer operational time and providing extra electron donors, longer chain organic acids (Butyrate) and alcohols (Butanol and Hexanol) were produced, concluding MES is a promising technology alternative to petrochemical production