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This thesis presents the development of a tendon driven continuum robot segment with a modular design. This work begins by reviewing existing literature surrounding continuum and modular robotics to better understand the current state of the art; and look for opportunities to make a novel contribution. The proposed design fills gaps in current research by showing a significant lifting capabilities due to a novel interlocking vertebrae system to restrict undesired torsional movement, while allowing bending in two degrees of freedom. Continuum segment modularity is achieved by embedding the actuation, control electronics and a battery in one end of the segment. This avoids the need for a bulky actuation unit and allows a varying numbers of segments; or a range of end effectors; to be connected via a universal interface integrated into the tip and the base. The design was developed through a number of iterations until a final solution was reached. The segment features a continuous flexible core made from soft silicone, combined with rigid 3D printed vertebrae evenly distributed along its length. It is actuated by two antagonistic tendon pairs, each of which is driven by a single geared DC motor in a custom design gearbox assembly. The design features a hollow central bore running its entire length which is demonstrated to be used for fluid flow and a control line channel for a tip mounted end effector. The three design iterations which feature the interlocking vertebrae were subjected to quantitative experiments to evaluate workspace, lifting capabilities and torsional rigidity. Finite element analysis was conducted to verify the strength of key components and optimise geometry. A compact electronics system was created that is capable of wired or wireless control, and allowing external or internal battery power was created. A control system was developed for the final iteration, using kinematics to successfully provide position control. The modular segment was demonstrated in a range of applications; fire fighting drone, a pick and place manipulator, and snake robot. The final segment was capable of lifting a 2.5 kg payload.

Thermoacoustic instability is one of the most significant problems faced in the design of some combustion systems. Thermoacoustic oscillations arise due to feedback between acoustic waves and unsteady heat release rate when the fluctuating heat release rate is sufficiently in phase with the unsteady pressure. The primary aim of designers is to design linearly stable thermoacoustic systems in which these dangerous oscillations do not arise. In thermoacoustics, adjoint-based sensitivity analysis has shown promise at predicting the parameters which have the most influence on the linear growth and decay rates as well as oscillation frequency observed during periods of linear growth and decay. Therefore, adjoint-based methods could prove to be a valuable tool for developing optimal passive control solutions. This thesis aims to develop novel experimental sensitivity analysis techniques and provide a first comparison with the predictions of adjoint-based sensitivity analysis. In this thesis experimental sensitivity analysis is performed on (i) a vertical electrically-driven Rijke tube, and (ii) a vertical flame-driven Rijke tube. On the electrically-driven Rijke tube, the feedback sensitivity is studied by investigating the shift in linear growth and decay rates and oscillation frequency observed during periods of linear growth and decay due to the introduction of a variety of passive control devices. On the flame-driven Rijke tube, the base-state sensitivity is studied by investigating how the linear growth and decay rates as well as oscillation frequency during periods of linear growth and decay change as the convective time delay of the flame is modified. Adjoint-based sensitivity analysis gives the shift in linear growth and decay rate and the oscillation frequency when parameters are changed. This thesis provides experimental measurements of the same quantities, for comparison with the numerical sensitivity analysis, opening up new avenues for the development, implementation and validation of optimal passive control strategies for more complex thermoacoustic systems.

In mental health trials there is concern that the control treatment (therapy) might be contaminated. For example, this might be due to it being delivered by a clinician (therapist) who has been trained in the active intervention. It is often suggested by investigators, reviewers and funders of clinical trial proposals that cluster randomisation, with clusters defined at the level at which treatment contamination is thought to occur (e.g. therapists), should be used to prevent contamination. This thesis explores statistical methodologies used to account for both treatment contamination in the control trial arm and non-compliance in the experimental arm when estimating treatment efficacy. It considers trials where treatment receipt is measured on a binary scale and develops methods to accommodate continuous measures of treatment receipt. The primary research objective was to compare the efficiency of two competing trial design options for evaluating efficacy in the presence of contamination. First, treatment allocation by cluster randomisation together with an estimator of the average treatment effect that accounts for clustered data. Second, allocation at the participant level, me-asurement of treatment receipt in all participants, and use of a randomisation-based estimator to target the complier average causal effect. Monte Carlo simulations under the two options with a binary measure of treatment receipt showed that the cluster randomisation design was more efficient under high levels of contamination, modest intraclass correlation coefficients and small cluster sizes. With a continuous measure of treatment receipt, the design with cluster randomisation was favoured more frequently as the difference between potential (counterfactual) doses became smaller, i.e. when there was greater non-adherence. The secondary research objective was to develop a novel randomisation-based efficacy estimator in trials with contamination and non-compliance measured on a continuous scale. Efficacy estimators were applied to a trial of a psychological intervention for people with poorly controlled type 2 diabetes. There was some treatment contamination and non-compliance in the trial but little evidence of treatment efficacy according to the analyses. The tertiary objective was to review problems and solutions associated with contamination in published trials of complex interventions in mental health. A main output from this project is the proposal of a novel valid estimator for evaluating efficacy and a demonstration of its utility. Another output is the provision of an online decision support tool (using the results from the simulations) to help those planning trials choose between the two competing design options for dealing with contamination.

One of the tenets of personalisation was that people using services could achieve greater citizenship and help to design better supports if they were able to direct innovation in services. Implicit in this was an assumption that people using services would be able to utilise their social capital (resources based on social networks), an asset which was not prioritised by previous approaches to service delivery. This thesis sought to identify if social capital was present and if it was being accessed to support the personalisation of services, comparing and contrasting the situation in services for older people and for people with learning disabilities. Whilst an initial hypothesis was that service providers for these different groups charged different rates due to different levels of social capital, no difference in social capital was established between these two groups. People did have social capital, but it was not mobilised by individuals or state actors responsible for commissioning support. This led to a consideration of street-level bureaucracy and the environment shaped by austerity and the Care Act. The study concludes that the implementation of personalisation has frustrated the use of social capital, such that it has not contributed to the transformation of care.

This thesis responds to a long-established consensus around the work of Samuel Beckett: namely, that it is singularly resistant to interpretation and yet its capacity to resist interpretation can be understood through Beckett’s own comments and through claims implicit in the work itself. In his fictional writings and critical essays as well as his correspondence and reported comments, Beckett frequently insists that “the labour of composition” does not involve the artist’s intellect, and accordingly he recommends a mode of reception that places little weight on the search for meanings or messages. Particularly in Beckett’s fictional texts, these recommendations are often accompanied by begrudging, oblique acknowledgements that the mode of reception they describe is an impossible one, since audiences and readers are consistently imagined to be possessed by a fundamental need to “make sense” of the work. This thesis elucidates the dialogue with that imagined need that underlies so much of Beckett’s work by drawing upon modern theoretical accounts of the inevitability of interpretation offered by thinkers such as Jacques Derrida, Peter Bürger, Barbara Herrnstein-Smith, Lionel Abel, Derek Attridge, and Charles Taylor. It is divided into four chapters that investigate how Beckett’s work operates under the weight of such logics of interpretation and that discuss the relation between Beckett’s anti-hermeneutic leanings and contemporaneous debates about artistic expression and proper modes of reception. In light of these discussions, each chapter re-evaluates one of Beckett’s rhetorical or stylistic strategies for “work[ing] on the nerves of the audience, not its intellect”: among these are de-centering or de-authorizing forms of multi-vocality; overt reliance on clichéd phrases and generic conventions; non-productive expenditures of words and events, particularly in the form of repetition; and meta-theatrical play with the unstable relationship between a performed play and a written script. Ultimately, the thesis shows that the Beckettian resistance to interpretation is not as singular as is commonly thought, and it opens up room for readings and adaptations of Beckett’s works that do not necessarily conform wholly to received notions of what Beckett would or would not have authorized.

There are many conflicting views about the blood-response to polymeric materials. In order to be satisfied that a material performs appropriately when used as a device in contact with blood it must be evaluated under relevant conditions. Central venous catheters suffer from problems related to thrombosis and embolism since they are implanted for very long periods of time within the vascular system. The aim of this study was to evaluate the most appropriate method for assessing catheter thrombogenicity, establish data for a number of relevant parameters and correlate these findings with various physico-chemica1 characteristics of the materials. Accordingly, a dynamic model was developed which allowed the assessment of platelet adhesion by measurement of "Cr-labelled platelets and platelet a-granule and lysosomal secretion by flow cytometry, after labelling with anti- GMPl40 and anti-GPS3 antibodies, in whole blood after the perfusion of the blood along the tubing at physiologically relevant shear rates (up to 1000 s") at 37OC. In addition, contact phase activation was assessed by measuring the time taken for an aliquot of plateletfree plasma to clot after contact with catheter material (partial thromboplastin time or P'IT) and the ability of the materials to cause factor XII activation by measuring the quantity of FXIIa-Cl-Inh complexes formed by enzyme-linked immunosorbent assay after the contact of platelet-free plasma with catheter tubing. An attempt was made at finding the identity of the proteins adsorbed onto silicone using a number of electrophoretic techniques. The ability of the materials to cause haemolysis and the cytotoxicity of an extract derived from the materials after SO days incubation in PBS including the identification of these potential leachables by supercritical fluid extraction was also investigated. In addition, these data were discussed in relation to parameters of surface roughness, as viewed by SEM and the ratio of hard and soft segments appearing at the material surface by XPS. It was found that significant differences could be detected in (i) platelet adhesion, where Pellethane was shown to have poor performance; (ii) a-granule release, where all the polyurethanes displayed better performance than any of the other materials and (iii) lysosomal granule release where most materials fared similarly, except for glass which was much worse. Silicone was shown to be best in the PIT assay, Pellethane worst. Surprisingly, no correlation was found with these results and those from FXIIa assay, where Desmopan and Davathane were highly active. New and important data on the initial activation kinetics and the ability of materials to activate factor XII are shown. Silicone produced the greatest haemolysis, PVC the greatest extract toxicity. No correlation was found between the physico-cbemical data and any of the biocompatibility data.

The name, title, literary persona and office of Vegetius are discussed in ch. 1, and although a firm decision is unjustified, comes stabuli seems bettter-attested than praefectus praetorio, come sacrarum largitionum or comes rei privatae. It is suggested that 'Vegetius' is only a cognomen to a true gentilicium 'Flavius'. The author's self-presentation as the Emperor's director of studies-cum-secretary is noticed. Ch. 2 provisionally locates Vegetius in Spanish horse-breeding senatorial circles, and treats his conventional Latin education with little or no Greek, his Vergil-reverence and orthodox Christianity. The date of Vegetius' Epitoma Rei Militaris is analysed in ch. 3 as being before the sack of Rome but in the aftermath of the battle of Adrianople. The Emperor-dedicatee is provisionally identified as Theodosius I. Scholarly debate on the question is thoroughly aired. The genre, literary persona and date of the Anonymus De Rebus Bellicis are argued in ch. 4 against the comparison of Vegetius. The Anonymus is characterized as a thaumaturgical sophist who complied his 'inventions' from older mechanical sources. A late-4th. or early 5th. century date is supported in opposition to the A.D. 360's. Ch. 5 argues that Vegetius' Epitome was intended to describe a Republican legionary organization adapted to late-antique Field armies with the unstated aim of reversing in detail and with specific advantages in mind the rapidly increasing barbarization of the army. Ch. 6 addresses the extent to which tactics and strategic constraints, arms and equipment and siegecraft were understood by Vegetius in contemporary terms, particularly as shown by Ammianus Marcellinus. It is argued in ch. 7 that the sources Vegetius used were late epitomes of the named sources, Cato, Celsus, Frontinus and Paternus, apart from Varro whom he used directly. Massive authorial intervention by Vegetius in the organization and content of the text is analysed.

Increasingly, online classes have been used to address the rising demand for statistics training and calls for improved curricula. However, little empirical research has examined the efficacy of online statistics courses. The present study sought to fill this niche by comparing the grades, attrition, pass rates, and satisfaction of 181 students enrolled in 4 face-to-face and 2 online introductory health science statistics courses. As methodological controls, the online and face-to-face curriculums were made as similar as possible, a single instructor taught all 6 classes, and blinded teaching assistants conducted all grading. In addition, differences in students' demographic characteristics, psychological factors, time constraints, and previous knowledge were assessed and controlled for prior to examining their learning outcomes. Contrary to past findings, face-to-face students outperformed online students in terms of their exam scores and pass rates. In addition, online students were found to be closer to graduation, less likely to be pursuing a Health Science degree, had taken more mathematics courses, placed lower value on their statistics training, displayed more negative attitudes toward statistics, and reported less confidence in their ability to learn statistics software. The implications of these findings for educators and researchers are examined in depth. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The synchrotron radiation based techniques of Surface Extended X Ray Absorption Fine Structure (SEXAFS) and Normal Incidence Standing X Ray Waves (NISXW) have been applied to Four adsorption systems. These involved atomic and molecular chemisorption on the low index planes of single crystal C'u and Ni surfaces. For the Cu(lll)(\/3 X v3) R30 system the NISXW technique has found a layer spacing of 1.81 ± 0.05A, this was consistent with an earlier result found by SEXAFS. For the Ni(100)c(2 X 2)Hg system the combined use of NISXW and SEXAFS was attempted. The SEXAFS study, however, was unsuccessful due to the difficulties of obtaining SEXAFS from core states of high angular momentum. These difficulties were attributed to delayed onset of photoemission from the mercury Mr edge and strong variations of the pure atomic X ray absorption coefficient in the EXAFS energy range. NISXW studies were more successful and yielded an adsorbate - substrate layer spacing of 0.60 ± 0.1A. This layer spacing is consistent with adsorption into the two fold bridge site at the Ni(100) surface rather than the more highly co-ordinated four fold site which might have been expected for a metallic bond. There are, however, some ambiguities in this assignment due to the lack of corroboration of this result by SEXAFS. For the remaining two systems the combined use of SEXAFS and NISXW was successful. The C'u( 111) C'H3S system was typical of most molecular chemisorption systems in that it possessed no long range order. For this system both the NISXW and SEXAFS techniques gave results indicative of reconstructive chemisorption. A corroborative interpretation of results for both techniques invlolved the adsorption of the CH3S group's sulphur atom into distorted three fold hollow sites at the Cu(lll) surface.Intra-inolecular scattering was also observed in this system. This scattering was between the carbon and sulphur atoms in the mercaptide (C'H3S) group, and SEXAFS analysis found a C-S bondlength of 1.88.4. This appears to be the first recorded case of intra- molecular^scattering in SEXAFS data. Simple chemisorption is also ruled out for the (v7 A v 7) R19.I -S on Cu(lll) surface. SEXAFS data for this system, like that for mercaptide, was dominated by a single shell and analysis of the polarization dependence of the SEXAFS amplitude for this shell gave an adsorbate-substrate bond angle, [3, of 67 ± 5°. This value is well outside the range expected for simple non reconstructive chemisorption of S into the high or low symmetry adsorption sites of the C'u( 111) surface. The NISXW data for this system was suggestive of a mixture of at least two distinct adsorbate- substrate layer spacings. One of which was well outside the range of values expected for simple chemisorption. The data from both experimental techniques can only be explained in terms of reconstructive chemisorption which forms a surface sulphide involving a mixed layer of C'u and S. This sulphide is believed to be of distorted tetrahedral co-ordination. This model can explain the two distinct adsorbate-substrate for S as well as the observed polarization dependence of the Cu-S bondlength.

At low temperatures the predominant energy loss mechanism for a Joule-heated two dimensional electron gas (2DEG) in a metal oxide semiconductor field effect transistor (MOSFET) is by acoustic phonon emission. By very accurately measuring the temperature gradient developed along the silicon substrate the phonon emission has been investigated as a function of electron concentration, device power, magnetic field and temperature. In zero magnetic field the results show the cut-off predicted theoretically in the maximum phonon momentum that can be emitted in the plane of the 2DEG for low electron concentrations. It is also found that the momentum of the emitted phonons perpendicular to the plane of the 2DEG is restricted by the width of the 2DEG for the high resistivity (1000 [omega]cm) substrates used. For carrier concentrations greater than 4.9 x 1016 m-2 phonon emission from an upper subband is seen. Electrical measurements indicate that the high mobility (1.2 m2 V-1 S-1) of the devices used leads to changes in the screening of scattering potentials by the electrons being important. This is also seen in the phonon emission experiments. Experiments performed in quantising magnetic fields up to 7 T show that for the powers used (0.2 uW mm-2 – 500 uW mm-2) the phonons emitted arise from Lars-Landau level scattering. Oscillations in the temperature of a thermometer situated directly opposite the middle of the 2DEG are attributed to the movement of the phonon emission to the corners of the 2DEG when the Fermi level is between Landau levels (the Quantum Hall regime). Other trends are attributed to the width of the Landau level limiting the maximum phonon energy that can be emitted. Attempts to use a stress tuned phonon filter to probe the frequency dependence of the phonon emission failed due to experimental difficulties.

This paper addresses a pressing need to accelerate domestic energy policy that will lower the carbon footprint of Britain’s domestic sector. A systems approach was taken to seek empirical evidence for an inherent problem of a low adoption of government programs created to incentivize low-carbon domestic retrofit. The purpose of research is to explore this low uptake with the aim of fashioning effective programs. This paper is intended for policymakers and researchers with an interest in meeting the UK’s 2050 emissions targets. Geopolitical and macroeconomic pressures on government may have hindered effective climate policy. Other financial interests may have influenced policy through endorsement of inefficient technologies for lowering emissions. Additionally, the war in Ukraine and a resulting energy crisis may affect solutions to these issues. These factors are presented as research questions and their effect on attitudes towards decarbonization are investigated. A two-phase approach was taken to explore public attitudes and to observe interactions with other stakeholders. Firstly, quantitative data on the effectiveness of solar power in the UK (for both domestic panels and grid electricity) was discussed, under a subjective viewpoint, for its use to inform the UK public (and guide policymakers). Secondly, to then address a need for a “bottom-up” investigation of societal opinions on decarbonization, energy, and retrofit programs, a questionnaire was distributed to a sample population. Phase 1 revealed that partial provision of scientific data may perpetuate public opinion in favor of PV and its incentivization by policymakers. Phase 2 unearthed socio-economic factors for programs such as grant amounts, and revealed socio-technical issues such as inadequate information on programs which, through technical miscomprehensions, are potentially abusable by energy system stakeholders with non-environmental agendas. This study concludes with three areas for attention to address domestic decarbonization issues presented in this paper: Incentivizing the right technologies; streamlining incentive programs; and finding the “right” advisory bodies to both guide government policy and to nurture public involvement in energy processes. Finally, this study proposes capitalization on 2022 geopolitical events to leverage long-term public interest in sustainability through its connection with concerns for the reliability and affordability aspects of energy security.

A prominent literature in political science holds that the meritocratic recruitment of public servants leads to gains in bureaucratic performance. It is also believed that this institution ought to also have positive effects on social cohesion, since the meritocratic distribution of civil service jobs theoretically enables members from all groups---ethnic minority or otherwise---to win coveted employment in the public sector. Looking predominantly at Southeast Asia, and drawing on large scale surveys and archival documents, this dissertation presents an argument and evidence to the contrary. Instead, under certain conditions, the introduction of meritocratic civil service reforms perpetuates existing inequalities, as privileged groups outperform marginalized groups on entrance exams and go on to staff administrative posts at disproportionately high rates, an outcome that heightens group-based resentment and weakens national solidarity.This dissertation develops its argument in the context of an important but understudied tension between the twinned goals of state-building and nation-building---a trade-off that comes most into focus in the Asian context. At the moment of independence, the leaders of Asian states faced the urgent task of state-building, which mostly involved recruiting a competent corps of public servants to staff the organs of their new governments. But these leaders were also tasked with nation-building to generate a sense of solidarity across their diverse populations. These twinned goals often existed---and continue to exist---in tension with one another. The most "competent" applicants for public service typically hailed from historically privileged groups who had received formal education: the forward castes in India, the Javanese in Indonesia, or the Chinese in Malaysia. A narrow focus on state-building would have led to a disproportionate representation of certain groups in the apparatus of the state, which would have surely detracted from the task of nation-building.

Sustainable behaviours are key to communities reaching their sustainability goals, with the use of public transportation being the focus of this study. To encourage transit use, public transportation agencies must use strategic communications to promote changes in behaviour. This is a case study of social media content from TriMet, the public transportation agency in Portland, Oregon. Content from 2019 posted to Facebook, Twitter, and Instagram was collected with a total of 741 posts (N=741). This content was coded to four major categories including broad purpose, content type, transportation type, and themes. Quantitative analysis was performed to note cooccurrences between coded items and correlations between coded items and engagement numbers. Following this, qualitative analysis was conducted to look closely at outliers, major themes, and notable trends. Points of interest are discussed including the uses of different platforms, the importance of visual branding, community engagement, information sharing, transit’s place in transportation networks, and the role of history in brand building. Recommendations are made for transit agencies based on the literature and analysis. This paper concludes with a research summary, limitations, future research directions, and an encouragement for communications scholars to tackle societal challenges through interdisciplinary research.

Identifying immune biomarkers in healthy humans that indicate an increased susceptibility to upper respiratory tract illness (URTI) is necessary to develop improved diagnostic and treatment strategies. URTI is associated with substantial socio-economic and personal cost. Small to moderate reductions in the severity and duration of illness could lead to substantial reductions in these costs. This thesis investigated the relationship between the immune system and URTI in healthy individuals utilising exercise as a model of stress. Chapter 2 (Section 2.2) reviews the effects of exercise on the immune system and URTI, with a particular focus on the way in which exercise can be used to better understand the role of the salivary antimicrobial proteins (AMPs) lactoferrin and lysozyme in host defence. Determining mucosal immune status, that is the condition of the immune system at body surfaces interfacing with the external environment, is necessary to understand the role of the immune system in host defence. Exercise-related disturbances in the immune system may increase susceptibility to URTI, particularly when prolonged intense exercise is undertaken frequently. Th e link between exercise-induced disturbances in immunity and URTI risk suggests that exercise may be a useful model by which to study the relationship between immunity and illness in healthy individuals.

The powerful short-latency, loading-mediated, inhibitory reflex of human inspiratory muscles is driven by proprioceptive muscle afferents of the chest wall and diaphragm, but the sites of afferent integration and the reflex circuit remain unclear. The inhibition is prolonged in asthma and obstructive sleep apnoea (OSA). This thesis investigates the reflex circuits, and also explores some factors that may unify the causation of the changes in the two diseases, such as airway and systemic inflammation or the chronic resistive loading of breathing. Chapter One summarises the functionality anatomy of the ventilatory muscles and their neural control and the previous studies of the inhibitory reflexes of breathing muscles. The common features of asthma and OSA, including inflammation, abnormal respiratory tract sensation and the chronic resistive loading of breathing muscles, are detailed. The reproducibility of measurement of this inhibitory reflex in human scalene muscles is validated in Chapter Two. In Chapter Three, the involvement of the carbon dioxide-sensitive inspiratory pattern-generating centres of the medulla in the integration of the reflex is investigated with matched volitional and automatic hyperpnoea. As considerable evidence suggests that voluntary inspiratory drive bypasses medullary centres, the absence of variation in the reflex between these conditions argues that the medullary pattern-generators are not involved in the integration of this inhibitory reflex. Chapter Four describes the use of a human model of acute upper airway inflammation to exclude a short-term role of inflammation in changing the reflex. Chapter Five assesses the effect of continuous positive airway pressure (CPAP) therapy on reflex abnormalities in OSA and confirms that the reflex abnormalities persist despite the correction of resistive loading of breathing in sleep. Chapter Six collates these findings and introduces the application of promising single motor unit techniques to this field.

Tax-based federal student aid--the Hope Tax Credit, Lifetime Learning Tax Credit and Tuition Deduction--marks a new paradigm for federal aid by offering tax incentives for postsecondary enrollment aimed at the middle-class. In this dissertation, I examine how the programs impact postsecondary enrollment, how colleges and universities respond to the programs, and I explore how taxpayers who are limited to one program select among the three options. In the first Chapter, I exploit policy-induced variation in tax-based aid eligibility to estimate its casual effect on college enrollment. I find that tax-based aid increases full-time enrollment in the first two years of college for 18-19 year-olds by 2.2 percentage points (6.7 percent). Yet, the enrollment increase comes at a steep price. Between 7 and 13 inframarginal youths are subsidized for each marginal youth that is induced to enroll in college. In the second chapter, I explore how colleges and universities respond to tax- based federal student aid. I demonstrate the importance of benefit incidence analysis by showing that the intended cost reductions of tax-based federal student aid are substantially offset by institutional price increases. Contrary to the goal of policymakers, I find that tax-based aid crowds out institutional aid dollar-for-dollar. Unfortunately, it is not clear how institutions utilize these captured resources, so that the ultimate incidence of the programs is uncertain. In the third chapter, I show that roughly one in five taxpayers who are eligible for more than one tax-based federal student aid program, and who are limited to one program per student per year, select a program that offers a smaller reduction in combined federal and state tax liability. I offer three explanations for this pattern of tax-based aid selection, including salience in program value, tax evasion and inertia in program selection. Collectively, the results from these chapters suggest that the benefits of tax- based federal student aid have come at a heavy price. The modest postsecondary enrollment increase for middle-income youths is achieved via a substantial transfer to colleges and universities, while complexity in program rules introduces substantial frictions for taxpayers

The indole moiety is extremely common in biologically active natural and un-natural products. Exploration and discovery of methods for generating the indole nucleus provides new and potentially more efficient options for synthetic approaches to indole-containing compounds. Vinylpyrroles have electron-rich pi systems and perform well as dienes in normal electron-demand Diels-Alder reactions with sufficiently electron-deficient dienophiles. The resulting substituted dihydro- or tetrahydroindoles are dehydrogenated to the corresponding indoles. Tosylation of pyrrole promotes acylation under Friedel-Crafts conditions at the difficult-to-access 3-position, which after reduction and dehydration gives 3-vinylpyrroles. These partially deactivated stable crystalline pyrroles have sufficient electron density to provide a novel and advantageous [4+2] cycloaddition route to indoles. Due to the high reactivity and consequent tendency of pyrroles to undergo undesired side-reactions, protecting groups are often desirable in pyrrole chemistry. However, the requirement for a sufficiently electron-rich diene, along with the sensitive nature of pyrroles, restricts the use of traditional blocking groups. Methylthio-protected 2-vinylpyrroles are shown to act as effective dienes in Diels-Alder reactions, demonstrating new blocking group techniques for chemistry involving sensitive pyrroles.

Genetic research projects currently can require enormous computing power to processes the vast quantities of data available. Further, DNA sequencing projects are generating data at an exponential rate greater than that of the development microprocessor technology; thus, new, faster methods and techniques of processing this data are needed. One common type of processing involves searching a sequence database for the most similar sequences. Here we present a distributed database search system that utilizes adaptive computing technologies. The search is performed using the Smith-Waterman algorithm, a common sequence comparison algorithm. To reduce the total search time, an initial search is performed using a version of the algorithm, implemented in adaptive computing hardware, which is designed to efficiently perform the initial search. A final search is performed using a complete version of the algorithm. This two-stage search, employing adaptive and distributed hardware, achieves a performance increase of several orders of magnitude over similar processor based systems.

Fuel processing is one of the essential parts for development of intermediate solid oxide fuel cells (IT-SOFC). Natural gas (methane) is considered as the most abundant and cost effective fuel for the production of hydrogen for IT-SOFC. The primary aim of this thesis is to use a novel precursor material—layered double hydroxide (LDH) – for developing a new type of cost effective, highly active and long lasting catalyst which can reform natural gas in IT-SOFC anode environment. Small amount of noble metals Pd, Rh and Pt are used as promoters to enhance the catalyst’s performance as while maintaining the cost relatively low. The research objectives are achieved by a series of studies including catalysts synthesis, characterisation and the catalytic activities. The thesis initially gives a comprehensive review on fuel cell and SOFC technology, steam methane reforming and reforming catalyst to provide better understanding of the research. Experimental studies include the effects of the synthetic conditions of the LDH precursors and thermal treatments on the physical, chemical behaviours and catalytic activities of the catalysts and promotional effects by noble metals. The LDH derived catalysts compositions, promoter quantities and operating conditions are optimised for the best performance in the IT-SOFC anode environment. A new method for the development of precursor sol for easy coating of the anode is developed and studied. The sol preparation is achieved by acid attack. The sol developed is found to produce better coating and has very high catalytic properties after activation. The catalysts developed were tested for their stability and self-activation ability to ensure its use in the commercial cells. The findings of the present study indicate that the catalysts developed show excellent catalytic performance and these catalysts have very high potential for further commercialisation in IT-SOFC.