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The thesis is an exploration of identity on the borderlands between South and Southeast Asia. Specifically, it establishes the nature of the cultural distinctness of one of the largest ethnic groups in the Chittagong Hill Tracts (CHT) in Bangladesh. The thesis presents the historical processes behind the hybridity of this ethnic group and how it eventually came to be under one self-identifying label - the Marma. The study employs various approaches to understanding the creation and reproduction of identity. From the maintenance of the boundaries of culture to the processes at work within culture through concepts such as creolization, syncretism, and entanglement. These latter theories point towards a fluid process of reconfiguring and recasting of structure or creating order from chaos, in response to changes in the environment. The research also explores other essentially different approaches that have similar conceptual outcomes, such as the theories that stress that traditional practice and ethnic identity are invented afresh according to present historical contexts and in response to both internal and/or external pressures. These different approaches help to piece together the various components of Marma cultural identity. The ethnographic data is presented in three parts with each section drawing upon the relevant theories to examine the field data on the Marma group. The thesis contributes a detailed monograph on the study of borderland cultures and demonstrates the value of applying several lenses to the study of identity in complex areas of the world.

The global imbalance between the healthcare provider and patient ratio, an increasingly elderly population and resource-limited settings have triggered the demand for point-of-care (POC) platforms, prompting the growth of personalised healthcare and homecare solutions. This thesis presents an investigation into an AI-enabled image-based system to perform automatic colourimetric tests in real-time. The case study of wet-chemical-based enzyme-linked immunosorbent assay (ELISA) and dry-chemical-based lateral flow assay (LFA) were utilised to design and develop an intelligent framework for chromaticity analysis with minimal user intervention or additional hardware attachments. The proposed system was designed by exploring state-of-the-art solutions for each component of an image-based colourimetric test, trial and error, and domain knowledge. At first, a reaction phase and time-dependent approach was proposed to track the dynamic changes in a colourimetric reaction by calculating the Euclidean distances. Subsequently, the final static stage of the reactions were considered and the images were pre-processed and segmented before applying vigorous noise removal techniques. The 10-fold cross-validated classifiers were trained with the optimum number of features using supervised machine learning. A completely separate testing dataset was utilised while testing the model. Additionally, a pre-trained model of deep learning was deployed to determine the type of colourimetric test, which can be integrated into the system where feasible. Based on our study, the reaction phase and time-dependent scheme was found to be more suitable for wet-chemical-based assays, particularly for low concentration samples. In addition to classification, the approach can assist in optimising the reaction time. However, due to the requirement of significant memory space by the video frames, the final system consisted of an alternative approach - considering only the reaction phase and time-independent scheme. On an ideal condition, the later approach provided more than 98% accuracy for colourimetric decision. Furthermore, the exploration of a pre-trained deep learning model revealed its strength in the test-type detection, instead providing the colourimetric classification. Therefore, deep learning was deployed to initiate the system based on the assay type (i.e. ELISA or LFA), which provided 100% accuracy. The system we demonstrated complies with the ASSURED criteria. As compared to the existing systems, the proposed intelligent and robust system with real-time processing capabilities has experienced a more extensive course of validation to enumerate the reliability of the system. Unlike most of the works in the literature, the proposed system provided the colourimetric prediction without any opto-mechanical attachment. Such an easy-to-use and computationally efficient system can be integrated into a server or deployed on a mobile platform to create better harmony between biochemical and computational complexity and eliminate the subjectivity of interpretation.

This study draws on the resource-based, knowledge-based, complementary and dynamic marketing capability theories in order to understand the internal dimensions of dynamic marketing capability (DMC) as well as the applicability of DMC in the exporting process. Specifically, this thesis investigates the multi-level structure of DMC, and also explores the crucial role of DMC in implementing knowledge-based resources to better value offerings within adverse market conditions. This study develops an integrated conceptual model that shows how knowledge-based resources and knowledge management capabilities enhance export performance. This research has employed structural equation modeling to understand the causal relationships through information from 315 personal interview-based surveys of export-oriented manufacturing and IT service organisations in Bangladesh. The results reveal that the DMC is a multi-level higher-order reflective construct that consists of four higher-order marketing capabilities. The findings show that DMC mediates the exporter's international ambidexterity dimensions (i.e. market exploration and market exploitation) to improve export performance under the lens of unpredictable market conditions and aggressive competitive pressures. In particular, this research identifies that DMC is a knowledge management process through which internationalisation knowledge can be implemented to satisfy customers' demands in exporting environments. The findings provide fresh insights by showing that the development of DMC is a complex process and it is not an ordinary marketing capability. An exporting organisation should adjust its accumulated internationalisation knowledge and knowledge management marketing capabilities in order to mitigate threats of radical market changes and satisfy its customers' demands better than other major export competitors.

Purpose: The thesis sets out to investigate the different upgrading strategies adopted by suppliers, the firm-level and relational conditions driving these, and their implications for employees' working and personal lives. The study is based on 18 Bangladeshi garment manufacturing firms involved in a specific form of international outsourcing relationship with their buyers, namely, tacit promissory contracting. Within this relational arrangement, the studied firms have been engaged in recurrent discrete transactions with the same buyers since their inception, but without the existence of any original legally binding written agreement. Design: The study adopts a multiple case study approach. Face-to-face interviews have been conducted with 25 owners/managers of the studied firms and 35 workers of those firms. Additionally, organisational documents and local newspaper articles have been collected wherever possible. The data analysis has been conducted using template analysis and fuzzy set analysis. Findings: The analysis has led to three key findings. First, the small suppliers have mainly focused on output (capacity) enhancement in their initiation of economic upgrading. In contrast, relatively larger firms have concentrated on higher value-adding actions. The social upgrading strategies of the small firms have mainly involved implementing measurable dimensions of the codes, while, in the case of large and medium sized firms, these have also involved addressing more sophisticated rights of the workers. Second, the suppliers are more eager to unilaterally pursue economic upgrading compared to undertaking social upgrading. Third, the upgrading initiatives have generated mixed results for workers in different sized firms. Their socially grounded needs have been neglected in the process of implementing the labour standards prescribed by the buyers. Originality: The thesis contributes to the IB and GVC literatures in three ways. First, the thesis elucidates a to-date unexplored form of international outsourcing relationship, namely tacit promissory contracting. Second, the thesis has emphasised the role of suppliers as the initiators of their firm-level upgrading strategies. Third, the study has revealed the broader implications of upgrading strategies by identifying the root causes of the problems associated with them, including their human rights implications. The study advances understanding in IB by moving beyond the typical MNE-centric approach and placing central focus on suppliers, along with integrating the voices of their workers. It has also identified the limitations of the social upgrading approach in GVC and has pointed out how focusing on a wider range of human rights would yield more insights into this concept.

Socio-ecological changes, brought about by the rapid growth of the aquaculture industry and the increased occurrence of climatic shocks and stresses, have significantly affected the livelihood dynamics of coastal communities in Asia. Empirical studies, to date, have largely provided a snapshot of the impacts and responses to a particular disturbance at a single spatial scale at a given time, often assessing the characteristics that make certain populations more vulnerable than others. To ensure equitable and environmentally sustainable livelihoods in the future, it is essential to unpack the complex social and ecological dynamics that drive long-term changes in a system’s configurations and shape the adaptive capacities of actors within the system. This study, therefore, explores the drivers, differential livelihood adaptations and well-being outcomes of socio-ecological change in coastal Bangladesh, using poverty as central lens for differentiation. The study takes a socio-ecological systems approach, whereby insights from vulnerability, resilience, political ecology, livelihoods, adaptation, poverty and human well-being are integrated into an interdisciplinary conceptual framework. A mixed methods approach was used to collect empirical evidence from two communities, both of which underwent transformations in farming systems when maintenance of the status quo through incremental adaptation was no longer feasible. Findings show that in the absence of good governance, social power resulting from high wealth status and associated political ties can steer the direction of socio-ecological change to one that is desirable for a small group of powerful stakeholders and completely undesirable for others. Differences in wealth status lead to differences in adaptive capacity; however, changes in vulnerability contexts brought about by power dynamics further exacerbate these inequalities. While resource constraints can restrict a household’s livelihood adaptation options, its adaptation space can also become narrower through negative externalities arising from the activities of other households. This can push some households towards downward trajectories, locking them in a poverty trap. In contrast, good governance and wider participation in decision making, can shift the farming system to one that is desirable for the majority of stakeholders. The study emphasises that resilience building through transformational adaptation should account for the heterogeneous values, interests and needs of different households. This can translate into more equitable adaptive capacities and prevent the system from embarking on a maladaptive trajectory in the future.

This thesis describes the development and application of novel techniques to reduce the EEG artefacts at source during the simultaneous acquisition of EEG and fMRI data. The work described in this thesis was carried out by the author in the Sir Peter Mansfield Magnetic Resonance Centre, School of Physics & Astronomy at the University of Nottingham, between October 2010 and January 2013. Large artefacts compromise EEG data quality during simultaneous fMRI. These artefact voltages pose heavy demands on the bandwidth and dynamic range of EEG amplifiers and mean that even small fractional variations in the artefact voltages give rise to significant residual artefacts after correction, which can easily swamp signals from brain activity. Therefore any intrinsic reduction in the magnitude of the artefacts would be highly advantageous, allowing data with a higher bandwidth to be acquired without amplifier saturation, and facilitating improved detection of brain activity. This thesis firstly explores a new method for reducing the gradient artefact (GA), which is induced in EEG data recorded during concurrent MRI, by investigating the effects of the cable configuration on the characteristics of the GA. This work showed that the GA amplitude and its sensitivity to movement of the cabling is reduced by minimising wire loop areas in the cabling between the EEG cap and amplifier. Another novel approach for reducing the magnitude and variability of the artefacts is the use of an EEG cap that incorporates electrodes embedded in a reference layer, which has a similar conductivity to tissue and is electrically isolated from the scalp. With this arrangement, the artefact voltages produced on the reference layer leads are theoretically similar to those induced in the scalp leads, but neuronal signals are not detected in the reference layer. Therefore taking the difference of the voltages in the reference and scalp channels should reduce the artefacts, without affecting sensitivity to neuronal signals. The theoretical efficacy of artefact correction that can be achieved by using this new reference layer artefact subtraction (RLAS) method was investigated. This was done through separate electromagnetic simulations of the artefacts induced in a hemispherical reference layer and a spherical volume conductor in a time-varying magnetic field and the results showed that similar artefacts are induced on the surface of both conductors. Simulations are also performed to find the optimal design for an RLAS system, by varying the geometry of the system. A simple experimental realisation of the RLAS system was implemented to investigate the degree of artefact attenuation that can be achieved via RLAS. Through a series of experiments on phantoms and human subjects, it is shown here that RLAS significantly reduces the GA, pulse (PA) and motion (MA) artefacts, while allowing accurate recording of neuronal signals. The results indicate that RLAS generally outperforms the standard artefact correction method, average artefact subtraction (AAS), in the removal of the GA and PA when motion is present, while the combination of RLAS and AAS always produces higher artefact attenuation than AAS alone. Additionally, this work demonstrates that RLAS greatly attenuates the unpredictable and highly variable MA that are very hard to remove using post-processing methods.

Polyphenols are known to be major inhibitors of dietary non-haem iron bioavailability, mainly through their action as iron chelators. In this present study Caco-2 cells were used to investigate the influence of quercetin, the most abundant flavonol in the diet, on non-haem iron bioavailability using 55Fe, and the gene expression of intestinal iron transporters as measured via qPCR. Chronic exposure to quercetin (24 hours) had no significant effect on iron uptake but iron efflux was significantly decreased. Consistent with this, qPCR analysis revealed a significant decrease in basolateral transport genes ferroportin (FPN) and hephaestin expression suggesting polyphenols may have direct gene regulatory effects. Exploring the cellular mechanisms underlying quercetin-induced FPN down-regulation, transfection of 5’FPN promoter constructs showed quercetin did not affect activity but did decrease FPN1A mRNA whilst increasing FPN1B expression; this suggests that although FPN1B is specific to intestinal epithelial cells, FPN1A remains the major isoform. FPN 3’UTR miRNA array analysis identified candidate hsa-miR-17-3p to be significantly activated by quercetin (1.5 fold) and qPCR validation confirmed up-regulation of 101 ± 25.1 -fold (p<0.01). This represents a novel mechanism of quercetin-induced miRNA-mediated regulation of FPN. In HepG2 cells quercetin stimulated hepcidin expression and inhibited ferroportin gene expression; this may provide an additional means of regulating systemic iron levels. Quercetin was shown to be both pro- and anti- proliferative/apoptotic dependent on the concentration used which may have beneficial consequences for liver pathology of iron-overload diseases. In contrast to findings in Caco-2 cells, in Thp1 macrophages quercetin caused a significant dose-dependent increase in FPN expression. Furthermore, quercetin induced both FPN1A and 1B promoter activities. This strongly implies that quercetin acts at the level of the FPN promoter to increase FPN expression - an effect specific to macrophages only. This demonstrates that quercetin has cell-specific effects and its actions on FPN are differentially regulated dependent on cell/tissue type. The results show that quercetin can have multiple effects on iron homeostasis. Given its relatively long half-life in the circulation, repeated dietary intake of quercetin could lead to plasma accumulation in vivo. This may have important consequences for conditions that are low in iron such as anaemia; alternatively it has therapeutic potential for iron overload diseases such as haemochromatosis. By deducing the mechanisms of how dietary polyphenols interact with our intake of essential nutrients such as iron, intake can be optimised to harness the potential benefits polyphenols have to offer.

Perinatal asphyxia remains a major cause of morbidity and mortality throughout the world. Despite improvements in obstetric and neonatal care there has been little improvement in rates of death and disability. Therapeutic hypothermia has recently been shown to be the only effective treatment following perinatal asphyxia. Selective Head Cooling (SHe) and Whole Body Cooling (WBe) are methods of applying therapeutic hypothermia. Yet the optimum method of cooling for maximum neuroprotection and minimum adverse effects remains unclear. We retrospectively compared four methods of cooling newborns following perinatal asphyxia. One method of SHC and three methods of WBC, using water-filled gloves, a coolant- filled mattress, and a water- filled body wrap. All methods maintained rectal t emperature within narrow target range. We found that WBC using a servo- controlled system minimised initial over-cooling and reduced subsequent fluctuation in rectal t emperature compared with manually-controlled WBC or SHe. We found similar variation in rectal temperature, heart rate, and mean arterial blood pressure using SHC and manually controlled WBe. We developed a technique of applying SHC with minimal systemic hypothermia as a t reatment for perinatal asphyxia in our established experimental model. We conducted a study to assess the neuroprotective and physiological effects of our technique compared to standard care under normothermic conditions. We did not find any difference in brain injury between treatment groups but increased mortality in the hypothermia group. We have.previously used a neuropathology score in our established model of perinatal asphyxia in order to assess treatment effects. Our neuropathology score incorporates subjective assessments of area injure'd and morphological cellular changes in several brain regions. We conducted quantitative cell counting to assess brain injury following perinatal asphyxia. Cell count correlated with neuropathology score in the putamen and hippocampus CA1 and we were able to validate our neuropathology score to assess outcome.

Carbon emissions generated by the building sector have come under stricter limits with the amendments to Approved Document L: Conservation of Fuel and Power of the building regulations for England and Wales. Building designs are now checked to ensure that new constructions have the designed capabilities to operate with a higher standard of efficiency. However, there are currently no means of ensuring that the mandatory improvements in design and construction are actually translating into real life improvements during the actual operation of the building. Assessment methodologies such as the Display Energy Certificate are applied annually. The large interval between audits has the potential risk that poor performance may go unnoticed for prolonged periods of time. Real time assessment of energy performance that is linked to legislative requirements would aid the process of ensuring reductions in carbon emissions occur in reality. Evaluating the energy performance in real time is not a straight forward task; commercial buildings are complex nonlinear dynamic systems with a number of operating states, functions and features. These factors need to be taken into consideration for the fair appraisal of energy performance. Condition monitoring has been applied extensively to the field of machine health, in which the state of a system is determined through measuring the parameters that are indicative of its health. Within this thesis, a unique method of real time energy performance has been developed along with the implementation of two condition monitoring strategies for the purposes of state evaluation and fault detection and diagnosis. Kernel based dimensionality techniques have recently gained popularity as a means of modelling nonlinear systems. It was found that the application of nonlinear condition monitoring strategies for determination of building state was proficient in determining slow developing faults and abrupt changes in building state. However, the occurrences of non-acceptable incipient changes in state were harder to detect. Hence the state evaluation techniques were complemented with component level fault detection and diagnosis techniques. These techniques have the combined ability to address the requirement for assessing the state of operation within a building to allow for fair appraisal of the energy performance.

A relatively large body of research has highlighted the high (or equal) risk of disordered eating in South-Asian populations in comparison to Caucasians, particularly in the UK. The literature review aimed to examine the empirical evidence for eating disorders and body dissatisfaction in South-Asian populations over the past decade. Through systematic searching a total of 16 studies were identified that met the inclusion criteria. These studies, not without limitations, highlighted the high level of disordered eating in young South-Asian populations compared to disordered eating in other ethnicities. The finding of higher body dissatisfaction in more Westernized South-Asian populations was also evidenced. Despite the findings that South-Asians are at equal risk as other ethnic groups for eating disorders, they remain under-represented in treatment services in the UK. The aim of the research report was to explore the eating disorder experience and journey into treatment for British South-Asian women who were in treatment in eating disorder services. Interpretative Phenomenological Analysis was used to analyse the transcripts from six participants. Three overarching themes emerged: the critical Asian society; the parental response: rejecting, tolerating and accepting; and the role of self and voicing needs. Implications for eating disorder services were made based on the experiences of these participants. The critical appraisal was an account of the research journey. Specifically, it highlighted the difficulties encountered along the process and how the present researcher managed these. It also incorporated the dilemmas for the present researcher in using a qualitative methodology.

In southern Bangladesh excessive levels of As in shallow groundwater have led to deeper groundwater becoming the main alternative source of As-free potable water. Hydrogeological configuration indicates that tube-wells pumping from these depths may be vulnerable to As breakthrough from shallow levels. The thesis explores a range of methods of representing lithological heterogeneity of the Bengal Aquifer System (BAS) in models of groundwater flow and travel time. The aim is to support models of arsenic (As) flux to the deep groundwater flow-system of BAS, and hence to aid assessment of the vulnerability of deep groundwater to invasion by As. The research uses an array of geological information including geophysical logs (n=12), hydrocarbon exploration data (n=11), and drillers' logs (n=589) from a 5000 km2 area to characterise the aquifer heterogeneity as a basis for alternative representations of hydrogeological structure in groundwater flow modelling. Groundwater samples from southern Bangladesh were analysed for 14C in order to determine groundwater age (n=23) and for hydrochemical (n=75) and isotopic (n=50) characterisation. A new hypothesis `SiHA (Silt-clay layers influence Hierarchical groundwater flow systems and Arsenic progression in aquifer)' is presented which integrates sedimentological heterogeneities, groundwater flow, and geochemical processes to explain the distribution and geological evolution of groundwater As in the aquifer. The hypothesis explains the spatio-vertical variability of groundwater As concentration by 'groundwater flow systems and differential flushing' in the aquifer. Groundwater flow models based on eight different yet plausible aquifer representations provide adequate simulations of hydraulic head, but contrasting implications for well catchments and travel times. The better representations are judged by comparing model outcomes of travel time with groundwater age determination using 14C. Comparisons demonstrate the importance of incorporating hydrostratigraphy and spatial heterogeneity in order to optimise model representations, and implications for the security of As-free deep groundwater in the BAS.

This thesis is an in-depth ethnographic study of the lives and multiple identities of six third generation British born Bangladeshis from Tower Hamlets. I argue that they find it difficult to be both British and Bangladeshi and are presented with difficult identity choices. Marginalised by mainstream British society due to ethno-cultural differences, many are also excluded from the Bangladeshi community due to their adoption of a seemingly more Western lifestyle. This complex situation brings into sharp focus the question of identity or identities. Are British born third generation Bangladeshis: • Bangladeshi ? • British ? • Muslim ? • A fusion of the three ? The central argument of this study is that this dual exclusion from both wider British society and Bangladeshi culture has forced many third generation Bangladeshis to seek alternative identities. In modern geo-politics, the emergence of Islam as a powerful mobilising entity for its followers, has led to the growth of religiously orientated identities in many younger generations across the Muslim diaspora. Numerous third generation Bangladeshis from Tower Hamlets have syncretised their Bangladeshi culture with their Western socialisation within an Islamic framework. The result is the construction of what I have termed a Br-Islamic identity. Enabling the subjects to identify comfortably with their multifaceted identities, Br-Islam challenges traditional Bangladeshi norms, values and rituals and also contests the complex notion of what it means to be ‘British’. Br-Islam allows many to be British, Bangladeshi and Muslim all at the same time, thus occupying more of a socio-political rather than theological space in wider society. Furthermore, as a dynamic and complex postmodern identity, Br-Islam requires a constantly changing view of ‘self’, responding to rapid social, economic and technological changes in modern society. I argue that Br-Islam is a fluid response to this crisis – a hybrid concept negotiating the complexities of modern society and providing its members with the voice, visibility, belonging, representation and confidence to partake in the wider political process.

A number of previous studies have assessed whether insider trades convey information to the market. Whilst lots of research has been undertaken in the past three decades, the issue is still contentious and there is ongoing debate concerning the legality and profitability of insider trading. Regulators restrict insider trading before any material news announcements, so that insider cannot take advantage of private information. Motivated by the studies in individual and aggregate insider trading, the objective of this thesis is to understand the role of signals that insiders send to the financial market about their companies when they trade, in general and to assess the role of insider trading in the context of initial public offerings (IPOs), particularly under lockup restrictions and the high information asymmetries inherent in IPOs.

The room temperature polymerising heterocyclic polymer system, poly(ethyl methacrylate)/tetrahydrofurfuryl methacrylate (PEM/THFM) has been shown previously to be biocompatible and supported tissue repair, specifically for bone and cartilage, and biologically inert when in contact with the dental pulp. It proved more effective, than other glassy methacrylates in the release of active species. The PEM/THFM system is a rigid material. The aim of this study was to develop and characterise the use of this system as a flexible patch, for application and retention to the buccal mucosa, thus facilitating sustained regulated release. Model species, dextrans, were used to represent macromolecular drugs whereby the effect of molecular weight could be studied. N-methyl pyrrolidone was added to the polymer system as a biocompatible plasticiser to enhance molecular mobility, and hence the transport of species. The effect of the addition of chitosan was also studied, due to its bioadhesiveness and permeation enhancing ability. A range of systems was investigated both in terms of water and species release. The release of the agent was measured by a fluorometer, the leachable components by HPLC and Confocal microscopy demonstrated the transport of water and active species through the system. Immunological and viability studies established whether the leachants or released components of the polymeric systems had an inflammatory or irritant action on `in vitro' stratified epithelium. The addition of N-methyl pyrrolidone, dextran and chitosan substantially increased water uptake, thus affecting the release kinetics. Analysis of the kinetics of water uptake showed Case I, combination of Case I and Case II, and Case II kinetics, depending on the systems studied. Dextran release was largely diffusion controlled, from which diffusion coefficients were calculated; the amount released varied between the systems studied.

Thermal barrier coatings (TBC's) are used to protect gas turbine blades from environmental degradation as well as to increase thermodynamic efficiency. Most TBC systems consist of a ceramic thermal barrier coating such as partially stabilized zirconia adhering to an oxidation resistant bond coat, which in turn is bonded to the turbine blade. This is required since partially stabilised zirconia will not readily bond to superalloys. However, the TBC can fail in service either by bond coat oxidation or thermal expansion mismatch between the bond coat and the TBC. A systematic literature survey has shown that the superalloy substrate material, type of bond coat selected, with the coating application techniques i.e. thermal spray or Electron Beam PVD (EBPVD) plays a fundamental role in determining the failure mechanisms involved. This program of work is concerned with the development of coatings with enhanced temperature capabilities for turbine blade applications by understanding the fundamental mechanisms responsible for adhesion between the nickel based turbine blade and zirconia based TBC. An understanding of the bonding mechanisms will allow the design of advanced coating systems with increased operating temperatures. This program of work introduces the Glow Discharge Optical Emission Spectroscopy (GDOES) technique, an atomic emission technique used for both bulk and depth profile analysis, which had not previously been applied to TBC's, and SEM and TEM in order to enhance understanding of failure modes in TBC systems and adhesion process. The results obtained from the studies indicate that the GDOES technique can be applied to depth profile bond coats and exposed TBC systems both qualitatively and semi-quantitatively. GDOES has been able to detect elements such as silicon and sodium that are in the ppm levels which are difficult/impossible to detect using EDX systems, and are very important in coating developments. In addition, as a preliminary guide GDOES has shown Ti diffusion from the superalloy substrate into the bond coat to be detrimental towards coating adhesion on most of the systems studied. The results of SEM and cross-sectional TEM on selected bond coat systems has shown the low cost Pt bond coat microstructure system to consist of TBC, Al2O3 bond coat and CMSX-4 superalloy substrate in all cases. The intermediate layer between the TBC and bond coat consists of Al2O3 which has been identified as responsible for maintaining the adhesion. Also identified is evidence of Ti segregation at the Al2O3/bond coat interface, known to lead to decohesion in coatings. Failure in the low cost Pt bond coat system has been identified as the decohesion between the interfacial layer of Al2O3 and the bond coat. The program of studies has enabled failure mechanisms and factors affecting bonding to be identified in low cost Pt bond coat systems, so that in future better coating systems with enhanced properties can be designed This should also ensure that improved reliability in engines and increased service life of turbine blades be achieved.

The aims and related hypotheses of this thesis were: a) To develop an antibody test that could be used as a tool to examine the gut humoral immune response to bacteria of the gut flora. In order to develop the antibody test, various antigens were prepared from the bacterial cell wall and their biological potentials were examined with human and murine cell lines. These tests could be combined with studies of other facets of gut immunity for which methods were already available, in order to explore active immunity and tolerance in the mucosal and systemic compartments. b) To examine and compare humoral immunity in the gut and serum of immunologically normal people from Edinburgh and Dhaka, in order to establish and test the following hypotheses: 1. In view of the probable higher antigenic load from a potentially contaminated environment, there would be evidence of gut damage and inflammation in the healthy people of Dhaka, and thus high levels of IgA, compared to people in Edinburgh. 2. In the developing country, the drive of high levels of humoral responses to bacteria would have the additional effect that antibodies to other gut antigens, such as foods, would be absent or of low titre. By studying patients with chronic colitis (inflammatory bowel disease), it might be possible to investigate how chronic gut inflammation affects specific antibodies and to identify the sources of gut antibodies, ie. serum-derived or locally produced. Prompted by the case of a patient with hypereosinophilic syndrome, high gut IgA concentrations and ulcerative colitis, the stimuli for eosinophil migration into the gut and eosinophil activation were examined and possible interaction with the regulation of humoral immunity investigated.

This thesis deals with the origin and development of the preventive detention legislation in Bangladesh, studying its necessity, relevance and desirability based on the judicial decisions. This study shows that the preventive detention legislation in Bangladesh runs contrary to the doctrines of fundamental rights; and the prejudicial acts for future commission of which are the basis for preventive detention are categorically included in the existing penal laws and can be dealt with more efficiently. The study investigates the preventive detention legislation and its impact over the fundamental rights of the citizens analysing the judicial decisions in Bangladesh. Four aspects are considered in this thesis. Firstly, it studies all the preventive detention legislation, Constitutions, and relevant statutes since their inception during the British period in the Indian sub-continent which have been carried through Pakistan till today. Secondly it investigates executive decisions to reflect the usage of the preventive detention legislation and views of the courts in this regard. Thirdly it analyses the definition and concept of 'subjective satisfaction of the executive authority and 'objective satisfaction of the Court' which has been the key factor detaining individuals. And fourthly, it provides an empirical study of the available number of cases from the Register of the High Court Division of the Supreme Court of Bangladesh to draw a scenario of preventive detention cases, decisions for and against the preventive detention orders made by the Executive authority in Bangladesh.

Eight methods were evaluated to assess potential soil S-supply to crops, and particularly to identify deficiencies in S-supply. Of these methods, three novel bioassays (sulphate production from incubation of amino acid-amended and elemental S-amended soil, and tissue S-concentrations of plants) proved better indicators (based on correlation with field crop response to S-fertilization) of S-supply than data from traditional chemical extractions. The above experiment was limited by the few soils (10) for which field S-response data was available. A second experiment was conducted with 54 soils using 6 of the 8 methods tested initially. Although no field data was available, a vast array of statistical procedures were performed which demonstrated that bioassays of soil S-supply produced related data sets but with no relation to data sets from chemical extractions. Consistent outlying of data for 2 Bangladesh soils in this experiment suggested an interesting apparent difference in the S-supply characteristics of temperate and tropical soils. The next phase of research aimed to investigate fertilizer S-supply to crops in soil. Firstly, the performance of gypsum and elemental-S were compared. Increased grain yield of barley was only achieved by gypsum application, although enhanced trace element nutrition from elemental S suggested that S-fertilization of crops influences the quality as well as the quantity of crop product. In a further pot experiment, enhancement of barley grain yield due to fertilizer S application was found only for crops grown on S-deficient soil. By labelling gypsum with 35S, the fate of fertilizer in a soil/grass system was assessed. Over 4 cuts in a 12 week period, grass removed about half of applied 35S with a further quarter left in the soil. The remainder was both in the roots and lost from the system. Less than 1 per cent of applied 35S was recovered from microbial biomass. The final experiment investigatead the method for determining S-content of the soil microbial biomass, highlighting the need for effective chloroform removal from soil and the importance of a suitable control (a non-fumigated but evacuated soil was suggested).

Recent breakthroughs in deep learning have revolutionized natural language processing, computer vision, and robotics. Nevertheless, reliable robot autonomy in unstructured environments remains elusive. Without the Internet-scale data available for language and vision, robotics faces a unique chicken-and-egg problem: robot learning requires large datasets from deployment at scale, but robot learning is not yet reliable enough for deployment at scale. We propose a scalable human-in-the-loop learning paradigm as a potential solution to this paradox, and we argue that it is the key ingredient behind the recent growth of large-scale robot deployments in applications such as autonomous driving and e-commerce order fulfillment. We develop novel formalisms, algorithms, benchmarks, systems, and applications for this setting and evaluate its performance in extensive simulation and physical experiments. This dissertation is composed of three complementary parts. In Part I, we propose novel algorithms and systems for interactive imitation learning, in which autonomous robots can actively query human supervisors for assistance when needed. In Part II, we introduce interactive fleet learning, which generalizes interactive imitation learning to multiple robots and multiple human supervisors. In Part III, we introduce and study systems for remote supervision of robot fleets over the Internet, enabling interactive fleet learning at a distance. Throughout this thesis, we design algorithms and systems with an emphasis on scalability in terms of the number of robots, number of humans, amount of human supervision required, dataset size, and distribution of physical locations. We conclude with a discussion of limitations and opportunities for future work.

Abstract: The oil sands are a critical source of unconventional fossil fuel. The Canadian oil sands are among the world’s largest crude oil deposits. Several oil sands extraction techniques have been developed in recent decades, including solvent-steam based bitumen extraction technology, an emerging process that has the potential to replace new greenfield projects. The solvent-steam process is based on the gravity drainage method, in which a mixture of steam and solvent is used to extract bitumen from a reservoir. The oil sands extraction process is an energy intensive process and results in large amount of greenhouse gas (GHG) emissions. There is a need to develop technologies which can help in the reduction of GHG emissions from oil sands extraction. In this study, a process simulation model was developed to assess the economics and GHG footprint of the solvent-steam extraction method for a plant established in Alberta, Canada using natural gas and Alberta’s grid mix electricity as the sources of energy. A capacity of 25,000 barrels per day of bitumen was considered, with hexane as the solvent. Sensitivity and uncertainty analyses were conducted to observe how the supply cost, energy consumption, and GHG emissions of the solvent-steam process change with changes in input parameters. The supply cost in the base case scenario is CAD 55.5/bbl at a 10% internal rate of return. Capital cost, solvent price, and transportation and blending cost affect the supply cost. The supply cost ranges from CAD 53 to 65.4 per bbl. The results also showed that energy consumption and associated GHG emissions are 0.92 GJ/bbl and 61.75 kgCO2eq/bbl, respectively. When uncertainty is considered, the energy consumption and GHG emissions range from 0.7 to 1.2 GJ/bbl and 49.7 to 82.6 kgCO2eq/bbl at a 90% confidence level, respectively. The overall GHG emissions are more sensitive to the steam-to-oil ratio (SOR) and heater efficiency compared to the solvent-to-oil ratio (SvOR) and emission factors. The use of natural gas combined cycle (NGCC) and biomass for producing heat and electrical energy was also assessed in order to explore their potential to reduce the GHG emissions of the process. Natural gas used to produce steam and solvent vapor is the prime contributor (97%) to overall GHG emissions. A less emission-intensive source of energy such as biomass to generate heat could reduce emissions by up to 91%. The findings of this study will assist oil sands industries and government in evaluating the economic and environmental feasibility of the solvent-steam bitumen extraction process.

Carbon nanotubes (CNTs) offer unique properties that have the potential to address multiple issues in industry and materials science. But the synthesis of CNTs is expensive because of multistep catalyst preparation using physical vapor deposition (PVD) or chemical vapor deposition (CVD) techniques. This dissertation aims to develop protocols for the preparation of catalyst and catalyst support materials and their assembly into monolayer film using wet chemistry for the synthesis of vertically aligned carbon nanotubes (VA-CNTs). Chapter 1 shows the properties of CNTs, synthetic methodologies, limitations in catalyst preparation, and assembly for large scale synthesis. Chapter 2 covers the synthesis of spherical shape AlOx nanoparticles and their physical and chemical characterization. Monolayer assembly of catalyst support and catalyst nanoparticles were discussed in chapter 3. Chapter 4 covers the synthesis of bimetallic AlOx-Fe2O3 nanoparticles catalyst that contain both catalyst and catalyst support materials. A detailed characterization of bimetallic AlOx-Fe2O3 nanoparticles were addressed to understand the physical and chemical nature of the particles. Chapter 5 shows successful synthesis of VA-CNTs from monolayer assembly of bimetallic AlOx-Fe2O3 nanorice at different temperatures. Overall, my dissertation discussed the premade catalyst and catalyst support nanoparticles synthesis and their assembly into monolayer film using organic crosslinking molecules for successful growth of VA-CNTs. In conclusion, this work will benefit the CNTs synthesis process in different metal or metal oxide substrate with an easy and inexpensive approach.

The vasculature is a highly intricate system of "highways" that shuttles blood from the heart to every tissue and organ in the human body. These vessels are responsible for carrying oxygen, trafficking hormones, delivering nutrients, and removing waste products from the body. The formation of a functioning vascular system depends on the close coordination of many cell types and, on the capillary level, specifically endothelial cells and pericytes as well as the surrounding protein microenvironment, known as the extracellular matrix (ECM). Impaired coordination amongst the cellular and protein constituents results in the improper functioning of the vascular network and can eventually contribute to the failure of organ systems. This dissertation research focuses on how improper ECM deposition affects vascular assembly. We utilized several approaches to affect ECM composition, specifically: 1) hypoxia exposure and 2) reducing ECM pharmacologically and utilizing lentiviral-mediated silencing of Type IV Collagen (Col-IV, gene Col4a1) expression. In these experimental settings, we observed downstream changes in the coordination between endothelial cells and pericytes while forming vascular networks. In short, this dissertation work suggests that excess ECM deposition, and particularly that of Col-IV, has unique deleterious effects on the developing vasculature as compared to reduced ECM deposition. The findings from this work suggest mechanisms underlying how the vasculature may be destabilized in hypoxia-associated pathologies, such as preeclampsia.

In gene expression, transcription of genes occurs resulting in either coding or non-coding RNA molecules that can undergo translation and serve cellular functions, respectively. During gene expression there is temporal control of RNA and protein molecule production, as well as the level at which they are made. Advancement of the antisense oligonucleotide technology and RNA interference have made the control of gene expression by nucleic acids a routine tool for laboratory research. The CRISPR/dCas9 system and a class of small non-coding RNAs known as PIWI-interacting RNAs (piRNAs) were the focus of this dissertation, both of which are relatively new techniques in the field of nucleic acid-based gene regulation.There is a prevalence of guanosine-rich sequences in the human genome and transcriptome and such sequences have a propensity to adopt secondary structures called G-quadruplexes (GQs). Despite abundant information and practical knowledge about the CRISPR-Cas9 technology, its capabilities and limitations in targeting DNA GQ structures have not yet been systematically investigated. In the CRISPR project, we utilized CRISPR/dCas9 system for targeting the vicinity of GQ forming sequence of human tyrosine hydroxylase (TH) gene promoter. In one study, we discovered that TH mRNA expression levels could both be up or down regulated in cellulo, depending on the location of the target sites. Given the propensity of secondary structures, such as, GQs in the human genome, it is imperative to learn about how the interaction between dCas9 and RNA polymerase (RNAP) is affected by the GQ structures. In another study, we used in vitro transcription to investigate the interactions between RNAP and dCas9 in the presence of GQ structure. When CRISPR-dCas9 complex targeting in the non-template strand, we found that dCas9 served as the dominant block of RNAP progression over GQ, whereas GQ predominates when targeting in the template strand.In the piRNA project, we applied the mechanistic approaches to understand how the homeostasis of piRNAs is maintained in cells. As part of that we elucidated the decay mechanism of piRNAs and our studies found that degradation of piRNAs is predominantly mediated via a 5' to 3' exoribonuclease pathway. Another goal of the piRNA project was to utilize a synthetic piRNA to establish a secondary biogenesis or ping-pong mechanism in human somatic cells. By using bioinformatics analysis, we established a list of 290 distinct ping-pong piRNAs that can be used to study the ping-pong mechanism in cellulo. We uncovered the dual gene knockdown by utilizing a synthetic piRNA, which is unprecedented compared to other known small natural RNAs (designed to be one sequence one target rule) used to regulate gene expression. This dual gene knockdown suggested that the ping-pong cycle is active in the human somatic cells. The direct evidence of the presence of secondary piRNA generation in the endogenous system is critical as a proof of ping-pong mechanism. Overall, we report mechanistically two distinct systems which are consequential in controlling gene expression.

Investments of public dollars on highway and transit infrastructure are influenced by the anticipated demands for highways and public transportations or traffic and transit ridership forecasts. The purpose of this study is to understand the accuracy of road traffic forecasts and transit ridership forecasts, to identify the factors that affect their accuracy, and to develop a method to estimate the uncertainty inherent in those forecasts. In addition, this research investigates the pre-pandemic decline in transit ridership across the US metro areas since 2012 and its influence on the accuracy of transit forecasts. The sample of 1,291 road projects from the United States and Europe compiled for this research shows that measured traffic is on average 6% lower than forecast volumes, with a mean absolute deviation of 17% from the forecast. Higher volume roads, higher functional classes, shorter time spans, and the use of travel models all improved accuracy. Unemployment rates also affected accuracy—traffic would be 1% greater than forecast on average, rather than 6% lower, if we adjust for higher unemployment during the post-recession years (2008 to 2014). Forecast accuracy was not consistent over time: more recent forecasts were more accurate, and the mean deviation changed direction. Similarly for 164 large-scale transit projects, the observed ridership was about 24.6% lower than forecasts on average. The accuracy depends on the mode, length of the project, year the forecast was produced as well as socio-economic and demographic changes from the production to observation year. In addition, we have found evidence of recent changes in transit demand to be affecting the transit ridership forecast accuracy. From 2012 to 2018, bus ridership decreased by almost 15% and rail ridership decreased by about 4% on average across the metropolitan areas in the United States. This decline is unexpected, because it coincided with the period of economic and demographic growth: indicators typically associated with rising transit ridership. We found that the advent of new mobility options in ride hailing services, bike and scooter shares as well as declining gas prices and increasing transit fares have the highest impact on ridership decline. Adjusting the ridership forecasts for these factors in a hypothetical scenario saw an improved transit ridership forecast performance. Despite the advances in modeling techniques and the availability of rich travel data over the years, expecting perfect forecasts (where observations are equal to the forecasts), may not be prudent because of its forward-facing nature. Forecasts need to convey their inherent uncertainty so that planners and policymakers can take that into account when they are making any decision about a project. The existing methods to quantify the uncertainty rely on flawed assumptions regarding input variability and interaction and are significantly resource intensive. An alternate method is one that considers the uncertainty inherent in the travel demand models themselves based on empirical evidence. In this research, I have developed a tool to quantify the uncertainty in traffic and transit ridership forecasts through a retrospective evaluation of the forecast accuracy from the two largest available databases of traffic and transit ridership forecasts. The factors associated with the accuracy and the recent decline in transit ridership lead the formulation of quantile regression as a new method to quantify the uncertainty in forecasts. Together with a consideration of decision intervals or breakpoints where a project decision might change, such ranges can be used to quantify project risk and produce better forecasts.

Natural and anthropogenic processes are emitting organic and inorganic pollutants, such as phenolic compounds, carbon dioxide (CO2), etc. in the atmosphere, which are increasing with time. In addition, to meet the energy demand of world’s growing population using nonrenewable fossil fuels are causing its depletion. Therefore, development of new technologies that can minimize atmospheric pollution and contribute to energy demand is imperative. Many methods or technologies have been developed for addressing those issues so far including advanced oxidation process, anaerobic biological treatments, and photocatalytic process. Among them, heterogenous semiconductor photocatalysis possesses clean and low-cost methodology and can simultaneously solve the problems of energy and environmental contamination. In this thesis, photocatalytic catechol (model pollutant) degradation with Degussa P25, a mixture of anatase and rutile phase of titanium dioxide (TiO2) and CO2 reduction with potassium and gallium-doped iron oxide (α-Fe2O3) are reported. The research uses Degussa P25 to study the degradation of catechol at air-solid interface because of low cost, stability, and abundant sources of TiO2. Catechol forms a chelate with TiO2 and shows absorption band in visible range through ligand-to-metal charge-transfer (LMCT) transition. The photocatalytic activity of catechol degradation on TiO2 surface are reported irradiating at λcut-off ≥ 320 nm, 400 nm, and 515 nm. The generation of reactive oxygen species (hydroxyl radical, superoxide anion radical, singlet oxygen) and redox pairs has been studied with scavengers. The chemical fates of scavengers and selectivity are also reported. Finally, the apparent quantum efficiency (AQE) for catechol loss and CO2 and carbon monoxide (CO) growths are determined. The amount of CO2 in the atmosphere can be minimized by reducing it to useful fuels photocatalytically. Potassium-doped iron oxide materials of varying potassium compositions (100 Fe:x K, 0 ≤ x ≤ 5) and calcination temperatures (400 °C, 500 °C, 600 °C, 700 °C, and 800 °C) are synthesized using incipient wetness impregnation method. The structure, composition, and properties of the catalysts are investigated by X-ray diffraction, thermal analysis and multiple spectroscopies, including: DRUV-vis, FTIR, Raman, ICP-AES, XPS and UPS, TEM with EDS and SAED. UV-visible light (λcut-off ≥ 295 nm) excites the catalysts in presence of pure CO2 or air (400 ppm CO2), both under a saturated water vapor atmosphere. The AQE for the CO(g) production shows maximum for 100 Fe:1 K. The surface-doped potassium photocatalyst enhances the photocatalytic efficiency by creating a more negative conduction band than the CO2/CO reduction potential. The role of potassium and nitrate has been explored. We also synthesize gallium-doped iron oxide using precipitation method with varying gallium compositions (100 Fe:x Ga, 0 ≤ x ≤ 5). The photocatalytic experiment similar to that of potassium-doped catalysts are performed. The material, 100 Fe:2 Ga shows greater reactivity creating a great scope for future studies. The studies of pollutant degradation and CO2 reduction with TiO2 and α-Fe2O3, respectively at air-solid interface provides a pathway to minimize the atmospheric pollution and contribute to the energy. They create a path to study more for other applications in air purification, water splitting, fuel production, etc. and development of efficient semiconductor photocatalyst.