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Despite a college degree being a prerequisite for economic and social mobility, many low-income students graduate at far lower rates than students from wealthier families. Existing research suggests that low-income students are more likely to attend college less prepared to succeed once they get there, experience financial challenges, have difficult navigating the complex higher education system, and have multiple obligations outside of their academic responsibilities, resulting in low completion rates. Much of the previous literature is rooted in in a deficit framework suggesting that low-income students are lacking or deficient if they are not academically successful. This study departs from the deficit paradigm by investigating how low-income students participating in a Student Support Services program at a Hispanic Serving Institution leverage their funds of knowledge and social capital to persist and graduate college. Findings suggest that low-income students have diverse needs and use a combination of relationships with family, peers, professional staff, and faculty to gain the knowledge, skills, and experiences that helped them overcome their barriers in college. Moreover, those who leave college should not be viewed negatively. As demonstrated by the participants who stopped out during their college career, they did not give up but left college temporarily to resolve the issues that kept them from staying enrolled, and those who did not return understand the importance of graduating and plan to return to college. As colleges and universities search to find ways to increase college completion, the findings from this study will add to our theoretical understanding of successful practices that keep low-income students on a college completion path rather than highlighting student deficits. [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.]

Technology adoption in early years education has been a consistent dilemma for teachers. Although research about the ill effects of technology use on school-going children prompts teachers to delay introducing technology in the early years, the need to prepare children for future schooling and the classroom productivity benefits prompt early years teachers to consider technology use. The COVID-19 global pandemic did not offer schools or pre-K nurseries in Dubai much time to train teaching staff to deliver lessons virtually; however, some teachers excelled at deploying technology while others faltered. In this context, the question of whether teachers' backgrounds played a role in technology adoption emerged and led to this research study. Specifically, this study explored how the cultural and educational backgrounds of teaching staff influenced their technology adoption. This study focused on early childhood education, where technology adoption historically has not been as prevalent as in K-12 schools. This qualitative research involved observations of 24 adults teaching staff using technology during eight lessons across two early years nursery settings in Dubai. Following the lesson observations, each participant completed Hofstede's cultural compass questionnaire, self-declared their educational backgrounds, and were interviewed by the researcher. The data originating from the questionnaires were analyzed using a deductive analysis process and two theoretical frameworks. What technology was observed being used was analyzed through the lens of Rogers' diffusions of innovations framework and participants' cultural backgrounds were analyzed using Hofstede's cultural dimensions framework. Any significant deviations in the Hofstede cultural compass questionnaire between the participants' cultural background and their home country cultures were further explored during the interview. The qualitative data generated from the participants' interviews were then analyzed through an inductive analysis process. This study contributed to the existing literature on the relationship between early years teaching staff's cultural and educational backgrounds and their technology use. It also provided a platform for early years teaching staff whose voices are often unheard. [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.]

There is clear evidence to support Rapid-Eye-Movement (REM) sleep behaviour disorder (RBD) as an early predictor of Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Those diagnosed with RBD enact their dreams and therefore present an abnormal characteristic of movement during REM sleep. This unusual sleep disorder presents an opportunity to better understand neurological degeneration and in-turn develop preventative medicine. However, manual polysomnograph (PSG) analysis is mandatory when diagnosing RBD, which demands complex monitoring equipment, specially trained staff, bed availability, and clinicians to interpret abundant amounts of data. Inevitably this process is time consuming and expensive, creating a demand for automated diagnostic support tools to better utilise the time of clinicians. The first aim of this thesis was to achieve automated sleep stage classification using signal processing and machine learning techniques. A total of 159 features were calculated using Electroencephalography (EEG), Electrooculography (EOG), and Electromyography (EMG) signals. After extracting the features a Random Forest (RF) algorithm was used to classify five sleep stages. With respect to REM stage classification, this technique achieved an accuracy of 93%, sensitivity of 63%, and specificity of 97% (five stage Cohen kappa of 0.63). After sleep staging, clinicians must manually identify abnormal REM sleep behaviour. Several methods have been proposed for RBD detection that use EMG recordings to objectively quantify abnormal REM movement. In this work we further develop these proven techniques with additional features that incorporate the relationship of muscle movement between sleep stages and general sleep architecture. Using an RF classifier with established and additional features, the performance of RBD detection was shown to improve upon established metrics (achieving 94% accuracy, 94% sensitivity, and 94% specificity). This technique used in combination with automated sleep staging sustained a high performance in RBD detection, with an accuracy, sensitivity, and specificity of 90%, 86%, and 94%, respectively. Lastly, this thesis investigated a minimal set of sensors to fully-automate the detection of RBD, integrating automated sleep staging followed by RBD detection without the need for cumbersome EEG sensors. This thesis demonstrated a costeffective, practical, and simple RBD identification support tool using an EOG and EMG sensor to achieve an accuracy, sensitivity, and specificity of 86%, 82%, and 90%, respectively.

The quadric-surfaced sludge digester (QSD), also known as the egg-shaped sludge digester, has proven its advantages over traditional cylindrical digesters recently. A reduction in operational cost is the dominant factor. Its shell can be described as a revolution of a parabola with the apex and base being either tapered or spherical. This shape provides a surface free of discontinuities, which is advantageous regarding the efficiency during mixing. Since the shape does not produce areas of inactive fluid motion within the tank, sludge settlement and an eventual grit build-up are avoided. The stresses developed in the shell of the sludge digester, vary along the meridian and equatorial diameters. A non-dimensional parameter, ξ, defines the height-to-diameter aspect ratio which is used to delineate the parametric boundary conditions of the shell's surface. Three groups of analyses were conducted to determine the orthogonal stresses in the shell of the QSD. The first-principles numerical models ran reasonably quickly, and many iterations were made during the study. The results showed that they were in within the range 5.34% to 7.2% to 2D FEA simulations. The 3D FEA simulations were within the range of 8.3% to 9.2% to the MATLAB time-history models. This is a good indicator that the first principles numerical models are an excellent time-saving method to predict the behaviour of the QSD under seismic excitation. Upon examining the criteria for the design, analysing the results for the 2D FEA simulations showed that the fill height is not a significant variable with sloshing however the 3D FEA showed that the hydrostatic pressure is a significant variable. With the maximum tensile stress of the 3D-printed ABS being 24.4 MPa, the overall maximum stress of 5.45 MPa, the material can be a viable option for the use of QSD construction in small island developing states (SIDS).

The prevocational sector within the educational landscape of Mauritius sets the scene for this research. This sector has witnessed considerable structural, curricular and functional changes over the years. Within the context of constant change, prevocational educators have been simultaneously in a position of object and agent of change. They have been continually required to review their professional practice with respect to curriculum content, pedagogy and resources which they use to meet new standards set by the official curriculum. This study aims at examining the professional development of prevocational educators by engaging in the debate of teacher agency. The learning processes and resources that are deployed by the educators in the enactment of the prevocational curriculum have been investigated along with their dispositions to effectively tap on their learning actions and opportunities. A major direction of this study has been to explore how teacher agency limited, changed or promoted these learning processes.

In cost-effectiveness analysis, outcomes are typically averaged across large groups to represent a patient population. Implementation and reimbursement decisions based on such analyses often ignore considerable heterogeneity in cost-effectiveness between patients. While good practice guidance for economic evaluations suggest including subgroup analysis, in practice this is frequently overlooked or underutilised. This thesis shows that failing to adequately represent heterogeneity in decision-making leads to an inefficient distribution of healthcare resources. This theory is applied in a study of cholesterol-reducing medication for the primary prevention of cardiovascular disease (CVD). Despite improvements in recent years, CVD remains a significant cause of mortality, morbidity, and health inequality around the world. Rates of the disease have begun to plateau in recent years and novel approaches to its prevention are required. Cholesterol reduction for the primary prevention of cardiovascular disease is a clinical area where better reflection of heterogeneity in cost-effectiveness could significantly improve current practice. Statins are a widely prescribed cholesterol-reducing medication which have recently come off patent. This has led them to become cheaper and cost-effective in a large proportion of CVD-free populations in high-income countries. PCSK9 inhibitors are a more expensive and more effective cholesterol-reducing medication. For both treatments, decision-makers must establish which groups they will prioritise for treatment. Through epidemiologic and health economic analysis, this thesis aims to establish optimal approaches for prioritising patients for cholesterol-reducing therapy. Preventive statin therapy is typically targeted at individuals estimated to have a high ten-year risk of developing CVD. However, individuals with the same ten-year risk may experience different outcomes from preventive treatment. The epidemiologic bases for three alternative approaches to the CVD prevention are discussed. These are: (i) continued use of ten-year risk scoring, (ii) novel decision mechanisms which incorporate ten-year risk, and (iii) direct use of decision-analytic models in clinical practice to guide treatment decisions. Several treatment policies may be characterised by one of the aforementioned approaches to prevention. These include: lowering the risk threshold for treatment initiation, improving the discrimination of risk scores with novel biomarker testing, age-stratified risk thresholds, absolute risk reduction-guided therapy, and outcome maximisation with decision-analytic models. Decision-analytic modelling was employed to assess the long-term effectiveness and cost-effectiveness of these policies. Additional analysis showed how decision-makers can signal demand for PCSK9 inhibitors and achieve welfare gains by reflecting heterogeneity in their decision-making. This thesis demonstrates the importance of reflecting heterogeneity in cost-effectiveness. It shows that standard care regarding the primary prevention of CVD often ignores heterogeneity, leading to suboptimal decision-making. This holds true for long-established, inexpensive treatments like statin therapy and novel, expensive treatments like PCSK9 inhibitors.

This thesis focuses on the determination of the position of events in the DEAP-3600 detector, a single phase, liquid argon dark matter direct detection experiment, which is currently taking its first year of data. The motivation for the existence of particle dark matter from prior research is outlined. The detector is described in detail as-built, along with the calibration systems and data acquisition equipment. The simulation of the detector is also described. The parameters of the simulated optical model are discussed, and their impact on the determination of event position is assessed. Work towards a more realistic detector simulation is discussed, showing agreement in basic variables important to reconstructing event position. The position reconstruction algorithms are described, and a method for improving one of the algorithms is developed which demonstrates better performance on known event source distributions. Timing information is also successfully implemented in position reconstruction, which will gain in importance as larger detectors are constructed. The position reconstruction is adapted to reconstruct an optical calibration source placed at a known location in the detector to within the error on the position of the source. The position reconstruction is then discussed as a means to calibrate the detector optical model using known source position distributions, and the performance of the more realistic detector simulation data is discussed. The reconstructed position and the surface alpha background, which position reconstruction is capable of rejecting, is then implemented in a profile likelihood ratio approach to a dark matter search analysis, in which, commonly, 90% C.L. upper limits are set on the spin-independent WIMP-nucleon scattering cross section. A preliminary upper limit setting analysis is then performed using a 220 day dataset and validated using an alternative analysis method.

With ever growing levels of urbanisation across the globe, a good understanding of canopy flows is paramount to reduce pollution in major cities and prevent unwanted aerodynamic loading on structures. The multi-scale nature of not only urban construction but that of natural environments requires a more complex modelling system be employed. Fractal geometries have only recently been investigated in turbulent flows, their multi-scale properties make them the logical choice for modelling and simulating flows involving such complex geometries. Additionally, in recent years the usage of Lattice Boltzmann Methods (LBM) vs Computational Fluid Dynamics (CFD) has increased, since LBM offers better computational efficiency and speed over CFD. However, the shortcomings of LBM still need to be benchmarked since macroscopic quantities of the flow are extracted using a probabilistic model of the flow at microscopic scales. A plan to investigate turbulent flows over a fractal and non-fractal obstacles has been presented by implementing a LBM numerical analysis over a range of Reynolds numbers (100-49410). The suitability of LBM's multiple dynamics models including: Bhatnagar Gross Krook (BGK), Multiple Relaxation Time (MRT) and Regularised Lattice Boltzmann (RLB) have been studied for high reynolds number cases. Results from LBM cases were compared to available experimental data and published literature, although, results of fractal cases were not mesh independent compelling agreement between all three tested obstacles show a significant validation of LBM as tool to investigate high Reynolds number flows.

Falciparum malaria remains one of the leading infectious causes of morbidity and mortality worldwide. Though the search for an effective vaccine has seen unprecedented advances in recent years and one of the leading vaccine candidates, RTS,S/AS01 is going to enter pilot deployments in Africa in 2018, there has been no vaccine that has demonstrated durable high level efficacy. This thesis describes four Phase I and Phase II clinical trials assessing novel pre-erythrocytic malaria vaccines in healthy adult UK volunteers. R21 has been developed at the Jenner Institute, University of Oxford. This is an improved RTS,S construct, an antigen derived from the pre-erythrocytic circumsporozoite protein, which is an abundant coat protein involved in sporozoite development and hepatocyte invasion. R21 comprises recombinant particles expressing the central repeat and the C-terminus of the circumsporozoite protein (CSP) fused to the Hepatitis B surface antigen (HBsAg), but without the excess of unfused HBsAg protein found in RTS,S. Both RTS,S and R21 predominantly function by inducing antibodies against the circumsporozoite protein. In addition to humoral immunity, it is widely recognised that T-cell mechanisms are likely to play an important role in malaria immunity and heterologous prime-boost regimes using viral-vectored vaccines have been shown to induce potent T-cell responses. ChAd63-MVA ME-TRAP is a regime that has been developed in the Jenner Institute and the first of the clinical trials described in Chapter 3 assesses the safety and immunogenicity of adjuvanting this regime with a novel saponin-based adjuvant, Matrix-MTM. This trial showed that this regime was safe, well tolerated and did not result in any immunological interference. R21 had never been administered to humans prior to the work described in this thesis. In Chapter 4, I describe two Phase I clinical trials assessing the safety and immunogenicity of R21 given at varying doses administered with two different adjuvants, Matrix-M (MM) and AS01B. Both these trials showed that R21 was safe and well tolerated when administered with either adjuvant and elicited comparable humoral immune responses to RTS,S/AS01B even at one-fifth of the dose (10μg). This formed the basis to test the efficacy of R21/MM, which had a favourable reactogenicity profile, using controlled human malaria infection in malaria-naïve UK volunteers. High level efficacy (> 80%) is reported in Chapter 5 with a three-dose schedule of 10/10/10μg R21/MM given 4 weeks apart. This provides the first evidence of proof-of-concept that this vaccine regime should be tested in malaria-endemic populations.

Several studies show that membrane transport mechanisms are regulated by signalling molecules. Recently, genome-wide screen analyses in C.elegans have enabled scientists to identify novel regulators in membrane trafficking and also signalling molecules which are found to couple with this machinery. Fibroblast growth factor (FGF) via binding to fibroblast growth factor receptor (FGFR) mediate signals which are essential in the development of an organism, patterning, cell migration and tissue homeostasis. Impaired FGFR-mediated signalling has been associated with various developmental, neoplastic, metabolic and neurological diseases and cancer. In this study, the potential role of FGFR-mediated signalling pathway as a regulator of membrane trafficking was investigated. The GFP-tagged yolk protein YP170-GFP trafficking was analysed in worms where 1) FGFR signalling cascade components were depleted by RNAi and 2) in mutant animals. From these results, it was found that the disruption of the genes egl-15 (FGFR), egl-17(FGF), let-756(FGF), sem-5, let-60, lin-45, mek-2, mpk-1 and plc-3 lead to abnormal localization of YP170-GFP, suggesting that signalling downstream of FGFR via activation of MAPK and PLC-γ pathway is regulating membrane transport. The route of trafficking was further investigated, to pinpoint which membrane step is regulated by worm FGFR, by analysing a number of GFP-tagged intracellular membrane markers in the intestine of Wild Type (WT) and FGFR mutant worms. FGFR mutant worms showed a significant difference in the localisation of several endosomal membrane markers, suggesting its regulatory role in early and recycling steps of endocytosis. Finally, the trafficking of transferrin in a mammalian NIH/3T3 cell line was investigated to identify the conservation of these membrane trafficking regulatory mechanisms between organisms. Results showed no significant changes in transferrin trafficking upon FGFR stimulation or inhibition.

BACKGROUND: Sudden cardiac death (SCD) in any young person is a tragic event with a significant number of life-years lost. Previous data from Italy suggest that pre-participation screening using an electrocardiogram (ECG) reduces the incidence of SCD in competitive athletes. However, the majority of SCD occurs in non-athletes within the general population. In the United Kingdom, state sponsored screening for cardiac disorders is confined to symptomatic individuals or those with a family history of inherited cardiac conditions or premature cardiac death. AIMS: To assess the feasibility and efficacy of screening, incorporating an ECG and point-ofcare echocardiography, in young individuals from the general population for cardiovascular conditions associated with SCD. METHODS: Between 2008-2012, 10,359 young individuals aged 14-35 years underwent screening by an attending cardiologist comprising a health questionnaire, physical examination and ECG. ECGs were analysed in accordance with the European Society of Cardiology (ESC} recommendations for ECG interpretation in athletes for Group-1 (trainingrelated) and Group-2 (potentially pathological) patterns. Group-2 ECG patterns warrant further cardiac evaluation. Individuals with findings raising suspicion of cardiomyopathy underwent on-site echocardiography. Individuals with abnormalities from the screening episode were referred for further evaluation for conditions associated with SCD and followed up annually to assess outcomes. Based on these data comparisons of the efficacy of different screening strategies were made and costs and cost effectiveness were calculated. RESULTS: Symptoms of a cardiovascular nature were reported in 44.2% of individuals, a family history of SCD or condition associated with SCD was reported in 3.8% and an abnormal physical examination occurred in 0.3% of individuals. ECG patterns suggestive of cardiac pathology were identified in 22.4% of individuals, predominantly due to abnormalities of QTc measurement. Male gender and black ethnicity demonstrated the strongest association with ESC Group-2 ECG patterns. Point-of-care echocardiography for individuals with suspicion of cardiomyopathy significantly reduced the number of patients requiring further evaluation as only 14.8% of these individuals demonstrated abnormal echocardiographic findings. Positive diagnosis of a cardiovascular condition associated with SCD was identified in 0.3% of individual;; (cardiomyopathy, n=6; primary electrical disease, n=17; Marfan syndrome, n=4). This screening strategy demonstrated a sensitivity of 100%, specificity of 93.2% and false-positive rate of 6.8% with an estimated cost of £106,141 per diagnosis made. CONCLUSIONS: Screening for conditions associated with SCD in the general population is feasible. A screening strategy incorporating the ECG and point-of-care echocardiography is associated with a high sensitivity and specificity and low false-positive rate as well as favourable cost analyses.

The use of video for teacher learning is a useful tool to support reflection and self-analysis. Video records have been successful in supporting teachers in learning to notice student thinking, a strong component in instructional expertise. The use of video provides permanent records of classroom lessons that can be viewed repeatedly (Sherin, 2001, 2007; van Es & Sherin, 2002, 2008.) It allows deep engagement and collaborative learning. Including the use of video in teacher preparation courses has successfully contributed to increasing pre-service teachers' attending and analyzing skills, necessary components of professional vision, (Santagata & Guarani, 2011; Sturmer, Konings, & Seidel, 2015). This qualitative study investigated pre-service teachers' use of self-video analysis as a tool to learn from their own practice. I examined the following research questions: (1) How does examining one's own teaching performance on video affect self- perceived reflection? (2) When pre-service teachers engage in self-reflective video analysis: (a) What teaching practices do they notice? (b) How do they identify needed change to teaching practices? This qualitative study included 12 pre-service teacher participants from the practicum courses of a teacher education program at one, public, Midwest University. Data collection included semi-structured interviews, focus group interview, and document collection about the use of video in self-reflection. Data analysis was inductive, following the Grounded Theory method (Corbin & Strauss, 1990). Findings indicate that pre-service teachers find self-video records useful to self-reflection through increasing their awareness of the classroom surroundings, offering a different perspective, supporting evaluation of their teaching with a visual record, and offering a record of their teaching growth. Pre-service teachers reported noticing the self-image characteristics, student engagement, and teaching behaviors during self-video review and perceived a change of practice in classroom management, awareness of classroom surroundings, lesson organization and implementation, and self-image characteristics of voice level and movement. Further research of the effects of self-video on pre-service teachers' self-reflection should consider the use of a framework or facilitation guide to support productive reflection. [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.]

This thesis is a critical investigation of the issues around the exclusion of individuals described as having ‘learning difficulties’ from higher education participation. As a qualitative inquiry it is situated within a ‘real life’ contemporary, interpretive and rapidly changing context. Using a postmodernist conceptual framework it draws upon the work of Foucault, Deleuze and Guattari. Adopting a case study approach, it explores the insights and experiences of a group of individuals who attempted to develop an undergraduate degree programme in the performing arts. Using one-to-one interviews, focus-group interviews and participant observations, its principal findings relate to a range of exclusionary barriers; these being attitudinal, cultural, educational, employment, financial and modern higher education. Its contribution is to (critical) disability studies, research and a critique of ‘learning difficulties’. Its postmodernist framework offers a theoretical map, insights into discourses of power/knowledge, and makes transparent the competing and contradictory discursive practices, challenging dualism and tree like structures. It concludes, suggesting that ‘learning difficulties’ is a constructed and re-constructed discourse. Its relationship with higher education is a feature of modern times, which comes to light in the turn to postmodernism. It rejects understandings of ‘learning difficulties’ that have taken-on ‘beliefs’, ‘realities’, ‘practices’ and ‘truths’ associated with ‘deficit’, ‘personal tragedy’, and ‘abnormality’. Moreover, individuals labelled as having ‘learning difficulties’, despite the rhetoric of ‘widening participation’, are intentionally positioned, and beset by barriers, and silenced, and excluded from degree level participation. Therefore, it calls for a radical re-think of the notion of ‘learning difficulties’, segregated provision, access to employment in theatre, associated HE policy and legislation, and to critical questions of modern higher education participation.

Mamalian protein ubiquitination and SUMOylation are reversible post translational modifications, which are involved in a multitude of important complex regulatory processes within the cell. Current mass spectrometry approaches that involve bottom-up proteomics to comprehensively analyse these modifications, have proved to be problematic. In this work, analytical approaches are carried out to improve and enhance the comprehensive analysis of these modifications. Tryptic proteolysis of ubiquitinated proteins results in the generation of isopeptides bearing adi-glycine (GG) remnant. Current mass spectrometry approaches used to identify these isopeptides are predominantly reliant on detecting the signature mass shift of the GG remnant (114.043 Da). The lack of sequence information from the GG remnant post MS/MS acquisition results in database search algorithms falsely identifiying these isopeptides. Reductive methylation chemistry was employed to derivatize these isopeptides. Upon collision induced dissociation of the isopeptides two robust ions were released from the iso-N-terminus of the GG remnant ; i) an a1’ ion at m/z 62.09, corresponding to the G of the remnant and ii) a b2’ ion at m/z 147.11, corresponding to the full GG remnant. Post-acquisition data extraction of these unique diagnostic ions demonstrated enhanced selectivity towards identifying these isopeptides. Tryptic proteolysis of SUMOylated proteins results in the generation of isopeptides bearing a substantial iso-C-terminal SUMO remnant. The CRA(K) (Consecutive Residue Addition tolysines (K)) approach combined independant use of proteolytic enzymes and unbiased consecutive residue addition of amino acids pertaining to these iso-C-terminal SUMOremnants, on all lysine residues. This approach enabled the identification of analytically useful novel wildtype isopeptides derived from the proteolysis of SUMO(1/2/3)ylated proteins, bearing GG, TGG and QTGG remnants. The analytically useful isopeptides derived from proteolysis of SUMO(2/3)ylated proteins lacked robust diagnostic information from their iso-C-terminal bearing TGG and QTGG remnants. Reductive methylation chemistry was utilised to derivatize these isopeptides and enabled diagnostic a’ and b’ ions to be released from their iso-N-termini; i) a1’ (m/z 133.13),b2’ (m/z 262.17) and b4’ (m/z 376.22) ions, corresponding to the QTGG remnant and ii) (m/z106.10), b2’ (m/z 191.14) and b3’ (m/z 248.14) ions, corresponding to the TGG remnant. Post-acquisition data extraction of these unique diagnostic ions, enabled comprehensive structural elucidation of these isopeptides and enhanced selectivity towards identification.

Standard catalyst characterisation techniques such as gas adsorption porosimetry and mercury porosimetry only account for some of the physical heterogeneity of the catalyst surface. They completely ignore the chemical heterogeneity present and in most cases consider pores present in the medium to be independent of each other. Thus, most results of characterisation (pore space descriptors such as BET surface area, BJH pore size distribution, mercury porosimetry surface area, etc.) are not accurate. This has been a major issue that remains to be resolved during the characterisation of fresh and coked catalysts. In this thesis, the use of a multi-component adsorption system is recommended as a step-change solution to this limitation. Two approaches are adopted. Firstly, integrated nitrogen-waternitrogen gas adsorption experiments are performed on fresh and coked catalysts. This established the significance of pore coupling by showing the presence of advanced adsorption. The method also helped to determine the location of coke deposits within catalysts and indicated that water vapour adsorption was a good probe to understand the sites responsible for coking. Secondly, coadsorption of immiscible liquids – cyclohexane and water – was performed on fresh and coked catalysts following which the displacement of cyclohexane by water was studied using NMR relaxometry and diffusometry. This novel approach takes the wettability of the surface into consideration, unlike the former methods. It is therefore a method that accounts for the chemical heterogeneity of the surface. It also helped determine the location of coke within catalysts. The different approaches are presented in the context of combustion of heavy oil in bitumen reservoirs, and the use of supercritical conditions that help to dissolve coke precursors in the isomerisation of 1-hexene. Thus, the solutions provided in this thesis are directions in which catalyst characterisation, especially distinguishing fresh and coked catalysts, and other porous materials, must be carried out.

Advanced signal enhancement techniques with application to speech and hearing are presented that are applied to areas including adaptive noise cancellation (ANC) in noisy speech signals, single channel noise reduction for speech enhancement, voice activity detection (VAD) and noise reduction in binaural hearing aids. The performance enhancement of the new techniques over competing approaches is presented. For the domains of ANC and single channel noise reduction, the use of Empirical Mode Decomposition (EMD) is the underpinning technique employed. A novel approach to dual-channel speech enhancement using Adaptive Empirical Mode Decomposition (SEAEMD) is also presented, when a noise reference is available. The new SEAEMD system incorporates the multi-resolution approach EMD with ANC for effective speech enhancement in stationary and non-stationary noise environments. Two novel Empirical Mode Decomposition based filtering (EMDF) algorithms are presented for single channel speech enhancement. The first system is designed to be particularly effective in low frequency noise environments. The second generalized EMDF system is designed to operate under other noisy conditions, with results presented for babble noise, military vehicle noise and car interior noise. It is shown that the proposed EMDF techniques enhance the speech more effectively than current speech enhancement approaches that use effective noise estimation routines. Speech systems such as hearing aids require fast and computationally inexpensive signal processing technologies. A new and computationally efficient 1-dimensional local binary pattern (1-D LBP) signal processing procedure is designed and applied to (i) signal segmentation and (ii) the VAD problem. Both applications use the underlying features extracted from the 1-D LBP. The simplicity and low computational complexity of 1-D LBP processing are demonstrated. A novel binaural noise reduction system is presented for steering the focus direction of a hearing aid (2 microphones per hearing aid) to additional directions as well as 0/180 degrees. The system places a spatial null in the direction of the target speaker to obtain a noise estimate. The noisy speech signal is then filtered to perform noise reduction, and thus focus on the target speaker located at the desired direction. The results demonstrate its performance at attenuating multiple directional interferers.

ALICE is built to measure the properties of strongly interacting matter created in heavy-ion collisions. In addition, taking advantage of the low pT acceptance in the central barrel, ALICE is playing an important role in understanding pp collisions with minimum bias triggers at LHC energies. The work presented in this thesis is based on pp data simulated by the ALICE collaboration and early data collected at a center-of-mass energy of 7 TeV. A procedure to calculate trigger efficiencies and an estimate of the systematic uncertainty due to the limited acceptance of the detector are shown. A kinematic comparison between Monte Carlo event generators, PYTHIA 6, PYTHIA 8 and PHOJET is also presented. To improve the description of diffraction in PYTHIA, a hard diffractive component was added to PYTHIA 8 in 2009, which is described. Finally a trigger with a high efficiency for picking diffractive events is used to select a sample with an enhanced diffractive component from pp data. These data are compared to Monte Carlo models, and the results are summarized with an estimate of the systematic uncertainty.

Brain Computer Interface (BCI) systems capture brain signals and convert them into commands without using peripheral nerves or muscles. This doctoral thesis embarks on advancing the design of P300 based BCI system using electroencephalogram (EEG) responses to visual and audio stimuli. This research work investigates techniques for pre processing, feature extraction as well as attempts some variations in paradigm design from a P300/0ddball paradigm perspective. Pre-processing is an important module in BCI systems. This thesis proposes a fully automated method (GALME-=ICA) to reduce artefacts effectively for an offline scenario. The method uses the recorded EEG channels only and does not require recorded EOG channels. The P300/0ddball systems were designed so as to reduce perceptual errors, thereby making them participant friendly. Few variations in paradigm design . reported here have not been attempted before. In one study, the spatial effect of the target stimuli location with respect to the non-target stimuli was explored. In another study limiting interference from irrelevant task related stimuli was studied. Results are discussed in terms of classification accuracies and bit rates. This thesis also proposes the usage of gamma band features with P300 time domain features for RSVP and audio based oddball paradigms for BCI based applications. An attractive integration of EEG-NIRS for monitoring participant concentration was also attempted. Preliminary results highlight the importance in selecting training datasets for good online classification results from an EEG viewpoint. There is no denying the fact that recent advances in BCI field have led researchers to explore new applications like cursor control and game control. However, there are many challenging problems which remain to be solved, before a commercial BCI system becomes a reality. Hence there is an urgent need to explore better system design and develop novel signal processing as well as machine learning algorithms. Imagination combined with practicality appears to be the key here. This Doctoral work is a step forward in this direction.

A four-cylinder, four-stroke, gasoline engine with direct injection fuel was commissioned and used to achieve CAI combustion. CAI combustion was achieved by employing short-duration, low-lift camshafts and early exhaust valve closure. Trapping sufficient volumes of exhaust residual provided the necessary thermal energy needed to initiate auto-ignition. The effects of valve opening durations on the CAI operation range were investigated at different air/fuel ratios, valve timings and injection timings. Furthermore the effect on engine performance, exhaust emissions, fuel consumption and combustion characteristics were also investigated. Methods which could be used for CAI combustion region enlargement were also studied. These included spark-assisted CAI at different EVC timings and valve durations, CAI operation at 2000 rpm and CAI combustion at late fuel injection timings

Despite recent advances in MRI, the structural basis for epilepsy in a significant proportion of patients remains unknown. This work investigates methods of MRI analysis that improve our detection of subtle structural abnormalities that are not seen on visual assessment of high resolution MRI. The additional information obtained from quantitative MRI analysis may also be informative in advancing knowledge about human cerebral development. We have developed automated methods for extracting information from MRI to derive quantitative measures, qMRI, of cerebral structure (grey and white matter volume, cortical thickness), connectivity (white matter surface area, callosal cross-sectional area) and complexity (gyrification index, fractal dimension). These methods were applied to control subjects (100) to investigate the structural relationships that exist within the normal brain and obtain a normal range for each measure in each region, revealing sex differences and regional asymmetries. Four adult subject groups were studied to explore the developmental and biological basis and clinical implications of these measures. These were subjects with known malformations of cerebral development (MCD) on visual MRI (82); PAX6 gene mutation (14); epilepsy patients in whom histopathological examination of cerebral tissue was available (100), of which 97 had undergone surgical resection for hippocampal sclerosis or focal cortical dysplasia and 3 in whom post mortem material was available; and patients with localisation-related epilepsy and normal visual MRI (51). The distribution and type of quantitative abnormalities did not correlate with the current classification of MCD, although those with diffuse MCD had more widespread quantitative structural abnormalities than those with focal MCD, even in visually normal areas. Subjects with PAX6 mutation had anatomical changes not previously described in humans. We were not able to detect microdysgenesis using our methods. Patients with quantitative structural abnormalities had a greater chance of having continuing seizures following surgical resection than could have been predicted on presurgical assessment. A third of patients with localisation-related epilepsy and normal qualitative MRI had quantitative abnormalities concordant with electroclinical data.

Human anti-mycobacterial immunity is largely successful as more than 90% of people infected with M. tuberculosis remain healthy. Interactions with environmental and pathogenic mycobacteria are believed to be responsible for priming favourable or unfavourable immune responses, respectively. The immune dysfunction in mycobacterioses was investigated by comparing different immune parameters in healthy people and tuberculosis patients. TB patients showed different proliferation and cytokine responses to sonicated mycobacterial antigens. Flow-cytometric analysis confirmed that the lymphocytes of TB patients showed phenotypic as well as functional changes in their properties. Detection of intracellular cytokines showed increased IL-4 but reduced IL-2 and IFN-gamma production by CD4 T cells of TB patients. This confirmed a switch from a Th1 to a Th2 response. The immunotherapy tested in this thesis consisted of an autoclaved preparation of M.vaccae, which was injected intradermally over the deltoid. In patients with mycobacterioses, M.vaccae immunotherapy was given in addition to the antimycobacterial chemotherapy. M.vaccae immunotherapy brought about an overall Th2 to Th1 shift in the majority of patients with drug-resistant pulmonary mycobacterioses which was apparently linked with clinical benefits. Patients with other immune disorders such as hay fever, chronic fatigue syndrome and different types of cancer, also showed similar changes to mycobacterioses in their immune parameters. This study supports the hypothesis that the Th1 to Th2 shift which occur in mycobacterioses and other diseases, can be reversed in some patients by M.vaccae immunotherapy. Greater understanding of immune parameters associated with immunopathological and protective immune processes is required to develop and improve immunotherapy.

Studies of mid-ocean ridges have provided evidence of magma chambers beneath both fast and intermediate spreading ridges. However no such features have been observed to date beneath slow spreading ridges. These contradictory observations are in direct conflict with seismic studies which reveal that the resulting crustal structures are similar and hence crustal structure is independent of the spreading rate. These latter observations in turn lead to the implication that the accretionary processes operating at all ridge types must also be similar. The aim of this study is to attempt to resolve between this discrepancy in geophysical observations of magma chambers at fast, intermediate and slow spreading ridges and investigate the nature of accretionary processes operating such that the same crustal structure is achieved. Therefore an apparently currently magmatically active section of the slow spreading Mid-Atlantic Ridge at 57 45'N on the Reykjanes Ridge, was selected as the target of a multidisciplinary geophysical experiment to be conducted aboard the RRS Charles Darwin in 1993. Wide-angle seismic data recorded using 10 digital ocean bottom seismometers were used to generate models of the crustal structure along and across-axis. These models were confirmed and further constrained by modelling of normal incidence seismic and gravity data and by comparison with the results of modelling controlled source electromagnetic data. The resultant models indicate that a magma chamber exists beneath the axial volcanic ridge studied, providing the first geophysical observation of such a feature at any slow spreading ridge. This magma chamber is similar in dimensions to those observed beneath fast and intermediate spreading ridges and consists of a thin, narrow sill-like body which appears to be continuous along-axis, and which is underlain by a region of partial melt extending almost to the Moho. This latter feature also appears to be both longer-lived and more extensive than the magma chamber. The 2.5 km depth to the top of the magma chamber is only slightly greater than that observed at fast spreading ridges, which indicates that magma chamber depth does not vary significantly with spreading rate. However, there ore insufficient data available to fully constrain and develop this relationship to its fullest. Therefore the results of this study indicate that the processes of crustal accretion occurring at all spreading ridges are similar, with the lack of observations of magma chambers being due to the fact that the periods of magmatic activity at slow spreading ridges are considerably more widely separated in both space and time than for fast and intermediate spreading ridges. The main difference however, appears to occur in the process of emplacement of layer 2A, which is observed to thicken off-axis at fast spreading ridges due to the less viscous lavas produced at these ridges being able to flow further off-axis. The results of this study, and of two other studies at slow spreading ridges, show that layer 2A is completely formed on-axis and thins off-axis due to extensional faulting. The remainder of the crust is completely emplaced, and the Moho formed, on-axis at all spreading rates.

The synthesis and structure of 1,2-quinone mono-oximes have been reviewed. The reaction of 3-hydroxyphenol, 3-hydroxy-2-aethylphenol, 3-hydroxy-5-methylphenol and N-acetyl-3-aminophenol with amyl nitrite/M(OEt) (M - Na or K) has been systematically examined. It has been found that the complex formed depends on the reaction temperature and phenol/M(OEt) ratio. Infra-red spectroscopic studies have shown that in the solid state 5-hydroxy-l,2-benzoquinone 2-oxime (hqoH,), 5-hydroxy-3-methyl-l,2-benzoquinone 2-oxime (3-MehqoH2), 5-hydroxy-6-methyl-l,2-benzoquinone 2-oxime (e-MehqoH,) and H-acetyl-5-amino- 1,2-benzoquinone 2-oxime (N-AcqoH) and their sodium and potassium complexes exist in the oximic form rather than the nitroso form. Nuclear magnetic resonance studies have also shown that in d,-DHSO solution hqoH,, 3-MehqoH, and 6-MehqoH} and their sodium complexes exist in one form only which is oximic in character. However, in DjO the results for the sodium complexes of hqoH, and e-MeqoH, indicate the presence of at least two species. In the case of the sodium 5-hydroxy-6-methyl-l,2-benzoquinone 2-oximate these species are oximic in character. An X-ray crystallographic study of e-HehqoH, has shown that in the solid state this compound exists in the 1,4- rather than the 1,2-quinone 2-oxlmic form. The synthesis of iron(II) complexes of hqoH,, 3-MehqoH] and 6-HehqoH] using the direct and the nitrosation methods was examined. The direct method gave rise to the complexes Fe(hqoH), OHjO, Fe(3-HehqoH), and Fe(6-MehqoH)2 '2H20 whereas the nitrosation method gave rise to ill-defined solids. Na[Fe(N-Acqo), ]-4H20 was obtained by nitrosation of N-acetyl-3-aminopnenol in the presence of Iron(II) ammonium sulphate. Hossbauer and magnetic studies indicate that Na[Fe(N-Acqo)j]-4H20 is a low spin iron(II) complex whereas the bischelates have properties indicative of the S - 1 spin state. In-vlvo assesment of the iron chelating ability of hqoHj, 3-MehqoH2, 6-MehqoH2, N-AcqoH , N,N-dimethyl-5- amino-1,2-benzoquinone 2-oxime and violuric acid was carried out using a normal rat model. The chelators hqoH, and 6-HehqoH2were found to be effective in removing iron when administered intra-muscularly but they also caused the excretion of magnesium. Their activity was lower than that of desferrioxamine and neither was effective when administered orally.

The purpose of this study was to explore the effects of globalization on K-12 language teacher education at Northern Arizona University (NAU) in terms of multilingual practices in the US, with reference to an English-only-state, Arizona. This study explored influences of globalization on K-12 language education practices in the US through teacher education/preparation programs of a US University in which the perspectives of prospective teachers/students and faculty of NAU and various published documents, such as policy statements and programs at federal and state levels were used as data sources of the study. In line with the purposes of the study, a review of the relevant literature, and consultation with experts in the field, the research questions and sub-questions were formulated and a mixed method study design was used. The data were collected from a sample of 200 prospective teachers/teacher candidates and from 24 faculty members and program administrators of NAU in the fall 2011. Three types of primary instruments--questionnaire, interview, and focus group discussion--along with some secondary data sources--policy statements/programs, legislation, and archives--were used to address the research questions and sub-questions. The collected data were triangulated and the findings were reported in the forms of themes and sub-themes. Some of the major themes that emerged from data were: Living in a globalized world with new realities; English-only policy of Arizona is anti-global and not futuristic; Teacher candidates are underprepared for diverse student populations; and National and State Common Core Standards are because of globalization. The findings of this study suggest that influences of globalization are visible on teacher education programs of NAU, in terms of the focus of the programs as well as the changing attitudes of prospective teachers/candidates and faculty members towards multilingualism. Most participants of this study felt that English-only policy of Arizona is a major barrier for the cognitive development of English language learners (ELLs) and is also hurting the state in several ways, such as limiting credentialing of teacher candidates beyond the border of Arizona in the US and abroad. Having its focus on teacher education programs of NAU, this study has implications for K-12 language teacher education policy and programs in the US. Given its exploratory purpose and its setting in one university in Arizona, any implications of the findings of this study need to be taken with caution. [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.]

Accounts of speech perception disagree on whether listeners perceive the acoustic signal (Diehl, Lotto, & Holt, 2004) or the vocal tract gestures that produce the signal (e.g., Fowler, 1986). In this dissertation, I outline a research program using a phenomenon called "perceptual compensation for coarticulation" (Mann, 1980) to examine this question regarding objects of speech perception. In Experiments 1A, 1B and 2, I examine non-speech contexts and evaluate their implications for perceptual compensation. Results from these experiments support a masking account of non-speech effects, while challenging a spectral contrast account. I then investigate the role of listener's state of perceptual attunement on compensation for coarticulation. In Experiment 3, I use sinewave speech (Remez et al., 1981) as contexts. Results show that sinewave speech precursors produce boundary shifts and that these effects don't depend on whether listeners report hearing them as speech or non-speech. In Experiment 4, I evaluate whether these sinewave effects are caused due to spectral contrast or gestural attunement by temporally inverting the first two formants of the contexts, while leaving F3 unaltered. Listeners fail to show boundary shifts despite the F3 region (critical from a spectral contrast perspective) being left unaltered. Finally in Experiment 5, I examine whether listeners' own coarticulatory actions cause boundary shifts, in an effort to examine how general. No effects of listeners' actions were detected. In conclusion, I suggest a careful understanding of the perceptual and motor state of the listeners is imperative for a complete understanding of speech perception. [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.]

A new three constant equation of state for fluids and fluid mixtures has been proposed. The equation contains three constants and is a more general form of the Peng-Robinson equation. In addition to the critical temperature and the critical pressure, two parameters are required to characterize a particular fluid. These parameters have been evaluated by minimizing the deviation in the saturated liquid densities while simultaneously satisfying the equilibrium criteria (equality of fugacities) along the saturation curve. Thus, prediction of volumetric properties in the saturation region and other regions of the phase diagram is improved, while accuracy in the prediction of vapour-liquid equilibrium is maintained. Parameters for hydrocarbons and nonhydrocarbons of importance to the synthetic fuel industry are presented. The new equation is extended to mixtures by using mixing rules similar to those used by Peng and Robinson. Only one binary interaction coefficient is sufficient for the accurate prediction of vapour-liquid equilibria. Optimum values of the binary interaction coefficients for hydrocarbon-hydrocarbon and hydrocarbon-non-hydrocarbon systems have been obtained using the new equation, the Peng-Robinson equation and the Soave modification of the Redlich-Kwong equation. The criterion used for selecting the optimum interaction coefficient is the minimization of deviations in bubble point pressures. The new equation has been tested for the prediction of volumetric behaviour of pure fluids and the phase and volumetric behaviour of binary, ternary and multicomponent systems. Comparisons with conventional equations (P-R, S-R-K, R-K and B-W-R-S) are shown. The applicability of van-der-Waals orie fluid model to _ generalised equations of state is demonstrated. The equations of Han and Starling, Simonet and-Behar and Chaudron et al have been compared for volumetric predictions. The Han and Starling equation has also been used with two sets of mixing rules to predict vapour-liquid equilibrium. The van-der-Waals one fluid model has been shown to be a simple and effective method of applying the complicated equations of state to the prediction of thermodynamic properties of mixtures. A generalised form of the corresponding states principle using two non-spherical reference fluids is presented. This represents an alternative method of extending the equation of state approach to fluids and fluid mixtures when experimental data are not available.

Transportation damage and disruptions will become increasingly common as the frequency of floods increases due to climate change. Given the size and cost of the transportation network construction, communities' mitigation measures should be supported by evaluations that cover both normal and disaster management phases. This thesis examines the criticality of road segments in the normal, flood response, and recovery phases, considering the effects on emergency services, healthcare, industry, education, recreation, and transit and analyses that whether a flood disrupts the operational trips of a company in Anderson County, South Carolina. A 100-year event and a 500-year flood event provides context for analyzing flood impacts to the time-based shortest paths, determined using ArcGIS Pro 3.1.3. Local and secondary roads were especially affected, with rerouting concentrating around the Anderson City area. Blocked road sections identified potentially vulnerable roads, and normalized betweenness centrality metrics identified community dependence on road segments for daily and emergency operations. While the quantity and dispersion of parks and grocery stores mitigated rerouting distance, other purposes faced challenges from impassable routes. Southeastern and southern regions as most impacted across purposes as per the analysis, suggesting targeted mitigation. The most critical routes before, during and after the flood were I-85, State Routes 28 and 81, and Federal Routes 29, 76, and 178. Also, the analysis for flood impacts on accessibility of a company in Anderson County was done using Boolean value assignment to the failed or non-failed links connecting the company with workforce, import and export trips. We found that the company undertaken for analysis would have disruption in importing and export of materials, but the workforce access was found to be not impacted as much. The routes that were found critically impacting the accessibility for the import and export were found to be SC 28 link, US 29 link, Highway 355 (New Pond Road link). This study highlights commonalities in road criticality across phases to support resilient transportation planning and sustainability. Based on both studies SC-28 link was found to be critical for flood disaster management phases, workforce accessibility, import and export and was found to be blocked due to 500-year flood.

Plastic waste is causing environmental problems due to its accumulation on land and in the oceans. Recycling plastic is both economically and environmentally beneficial; however, there are limited options available for disposing of plastic waste. The problem of plastic waste is global and requires immediate attention. One of the major obstacles to plastic recycling is the difficulty in separating different types of plastics, such as polyethylene and polypropylene, which leads to an increase in plastic waste. Although these plastics have desirable properties, they are not compatible in their solid and melt states, making it difficult to reuse them. This issue occurs not only with polyolefin mixtures but also with most plastics. There are different approaches to achieve sustainable plastics, such as using compatibilizers, chemical cycling, advanced sorting, and creating new biodegradable and petroleum-based polymers. This study aims to develop novel petroleum-based polyolefins that possess a unique structure, comparable thermal as well as potentially mechanical properties to polyethylene (PE) and isotactic-polypropylene (iPP) and are capable of forming co-crystalline phases after secondary reuse, enhancing their potential for reusability.Co-crystallizing different semicrystalline polymers is a challenge, as each polymer has its own kinetics of crystallization, chain conformation and packing structures in the crystalline region. Even low-density polyethylene cannot fully co-crystallize with high- density polyethylene. So far, only a few systems, such as stereo-complexes like poly(lactic acid)s and poly(methyl methacrylate)s, have been able to co-crystallize. However, these require specific mixing ratios that are not feasible in secondary recycling.Very recently, Hayano and Nakama synthesized a series of unique polyolefins named as hydrogenated poly(norbornene) (hPNB)s with different stereoregularity showing semicrystalline features with a wide melting temperature (Tm)s of 135–178 °C covering Tms of PE and iPP. Surprisingly, it was found that all syndio-, isotactic- and atactic- adopt trans conformations in the crystalline phase. In this thesis, I have systematically studied basic crystalline structure, morphology and molecular dynamics of stereoregular and irregular hPNBs Surprisingly, it was found that atactic (a)-hPNB shows the highest crystallinity and the longest crystal thickness among the three samples. By applying advanced solid-state NMR spectroscopy, it was found that only a-hPNB chains in crystalline region conduct unique molecular dynamics above crystal-crystal transition temperature (Tcc) and below Tm among three hPNBs. These findings in addition to conformational similarity indicate that configurational disorder coupled with conformation flexibility (CDCF) generates unique structural evolutions in semicrystalline polymers in the crystallin region . It is hypothesized that two conformationally similar but dynamically different a-hPNB ( mobile crystal) and s-hPNB ( fixed crystal) cocrystallize randomly in any composition. I studied thermal property, nano-phase structure, and molecular dynamics of a-/s-hPNB blends. Interestingly, a-/s-hPNB (3/1) blends show crystal-crystal transition as observed in a-hPNB. Notably, temperature-dependent proton spin-lattice relaxations in rotatory frame (T_1ρH) revealed nano-phase separations of a- and s-hPNBs within the co-crystalline phase. This phase separation was found to be associated with dynamic contrast between a-hPNB and s-hPNB inside the cocrystal. Remarkably, the phase separation was more pronounced with increase in temperature above Tcc. Furthermore, cooling the temperature resulted to reforming an original single co-crystalline phase. Such dynamic and structural heterogeneity challenge a traditional concept of polymer crystals having three-dimensional orders. I will provide discussion on this unique nano-phase reversibility in the co-crystalline phase in detail. Our experimental result recalls a recently proposed concept of polymer crystal being redefined as parallel packing of polymer chains. Finally, we investigated the impact of co-crystallizing stereo-regular and irregular hPNBs on microscopic molecular dynamics, thermal properties, and morphology. It was found that by adjusting the blending ratio, we can effectively tune and control thermal properties as well as morphology. In my discussion, I will delve into the mechanism behind these remarkable structure and properties from molecular level perspective. I firmly believe these acquired experimental results will provide basic principles in designing sustainable semicrystalline polymers.The development of novel petroleum-based polyolefins with unique structures and properties, such as hPNBs explored in this study, represents an important step forward in the search for more sustainable plastics, highlighting a promising approach to addressing the challenge of plastic recycling and reducing plastic waste.

Despite a college degree being a prerequisite for economic and social mobility, many low-income students graduate at far lower rates than students from wealthier families. Existing research suggests that low-income students are more likely to attend college less prepared to succeed once they get there, experience financial challenges, have difficult navigating the complex higher education system, and have multiple obligations outside of their academic responsibilities, resulting in low completion rates. Much of the previous literature is rooted in in a deficit framework suggesting that low-income students are lacking or deficient if they are not academically successful. This study departs from the deficit paradigm by investigating how low-income students participating in a Student Support Services program at a Hispanic Serving Institution leverage their funds of knowledge and social capital to persist and graduate college. Findings suggest that low-income students have diverse needs and use a combination of relationships with family, peers, professional staff, and faculty to gain the knowledge, skills, and experiences that helped them overcome their barriers in college. Moreover, those who leave college should not be viewed negatively. As demonstrated by the participants who stopped out during their college career, they did not give up but left college temporarily to resolve the issues that kept them from staying enrolled, and those who did not return understand the importance of graduating and plan to return to college. As colleges and universities search to find ways to increase college completion, the findings from this study will add to our theoretical understanding of successful practices that keep low-income students on a college completion path rather than highlighting student deficits.

Recently, cosmic rays (CRs) have emerged as a leading candidate for driving galactic winds. Small-scale processes can dramatically affect global wind properties. This thesis investigates how CRs can destabilize hydrodynamical flows in the circumgalactic medium (CGM) and extensively utilizes the newly developed two-moment method to model CR transport by self-confinement (streaming). To ensure the numerical method is robust, a series of tests are conducted to examine the behavior of the code at shocks. This examination led to the discovery of a new class of CR-modified shock solutions which matches with simulation very well. It is then used to study how sound waves are driven unstable by phase-shifted CR forces and CR heating. As the sound waves grow non-linear, they steepen into a quasi-periodic series of propagating shocks; the density jumps at shocks traps CRs by the bottleneck effect, creating staircase like structures in CR pressure profile. The staircase structure redistributes CR heating and forcing to highly localized regions and can enhance the CR pressure push on the CGM gas, driving stronger outflows. It is believed the shocks generated by the CR-driven acoustic instability could have distinct observational signatures, on ∼kpc scales. At last, the CGM is often believed to be unstable to the local thermal instability. Mass dropout from the instability, contrary to other heating or cooling source terms such as radiative cooling, triggers a boost in the CR heating rate and can lead to it dominating the energy budget of CGM gas flow if the magnetic field is sufficiently strong. This loss of thermal equilibrium triggers a loss of hydrostatic equilibrium, driving outflows with properties that vary drastically depending on whether the CR heating timescale is less than the free-fall timescale. If the magnetic field is weak, tangling of the field lines due to local thermal instability can trap CRs, causing a buildup of CR pressure and an uplift and re-circulation of cold gas. These results have implications on the mass and energy loading of winds, and the detection of intermediate velocity clouds at the inner CGM.

In this series of essays, I apply the tools of economics to a variety of real world problems. The first essay looks at the impact of a gun control regulation on mortality and crime. A third of US states have removed all restrictions on carrying concealed handguns. This might decrease crime by invisibly arming law-abiding citizens, or increase it by eliminating penalties for criminals. It could have no effect at all, because handguns are easily hidden, so anyone who wished to carry a gun was already doing so. I compare counties along the borders of states that liberalized concealed carry to contiguous counties in neighboring states that did not, using mortality and crime micro-data. I find that deregulation had no impact on homicide, violent crime, firearm mortality, firearm usage, or firearm ownership. The second essay, co-authored with Sajala Pandey, looks at the impact of an earthquake in Nepal on child development. Biologists have posited that prenatal maternal stress (PNMS) has an adverse impact on child development, possibly via the process of epigenetic imprinting which occurs during the first trimester. Researchers have attempted to study this link by using natural disasters as a source of exogenous variation. A shortcoming of these studies is that natural disasters may also affect prenatal healthcare provision, either by decreasing it’s provision (due to infrastructure being destroyed) or increasing it (thanks to aid flowing into the region.) We look at the impact of 2015 Earthquake in Nepal on children who were (a) in utero at the time of the earthquake and (b) in areas severely affected by it. Consistent with theories from PNMS, we find that the earthquake adversely impacted their height-for-age, and the effects were concentrated on individuals who were in the first trimester of gestation. These negative effects were entirely offset by an increase in the consumption of antenatal healthcare. We find that the earthquake resulted in a improvement in development indicators for those children who were in severely affected areas but not in-utero at the time of the earthquake, highlighting the importance of healthcare provision in early childhood. The third essay, co-authored with Andrew Copland, proposes a solution to the problem of assigning multiple scarce goods to agents in the absence of prices, for example assigning seats in courses to students in a university. Students submit a list of preferences over courses, a lottery for rankings is held, and an algorithm allocates each student their top available course, reversing their ranks at the end of each round. Then, for each student, the algorithm compares their outcomes to the outcomes generated by every alternative ordering they could have set. Whenever such revisions result in more preferred outcomes, their preferences are replaced with the alternative. Our solution is non-dictatorial and Pareto optimal. When it converges without encountering a loop, it is strategy-proof. It retains properties even in small economies. We compare our algorithm to alternatives.

The processes of globalization — characterized by global flows of people, technologies, capital, images, and information that shape people’s imagined worlds — continue to spur the growth of megacities and the concomitant health dilemmas therein. As globalization shapes both the practice and the idea of medicine and healthscapes, this transformation is translated into shifting desires, expectations, and identities for both physicians and patients in the clinical encounter — the focal points of this study. This dissertation project utilizes an ethnographic design (semi-structured interviews, participant observations, and archival research) over a 19-month period in Mumbai, India to examine the following question: How does the clinical encounter unfold in relation to the doctor-patient interaction to construct expectations? This study takes the following two premises: 1) A thick ethnographic description of the clinical encounter is fundamentally linked to the bi-directional shaping of local, global and micro, macro ideologies. 2) Biomedicine (its practitioners, its seekers, its associated clinical encounters, and its institutions) is a prominent focal point on which the concepts of identity and globalization pivot in Indian society. Therefore, this study of the doctor-patient interaction is framed to serve as a microscopic observation of macroscopic globalization forces. I interviewed physicians and patients and observed their clinical interactions at 3 Obstetrics/Gynecology clinical sites in Mumbai: a private clinic, a semi-private hospital, and a municipal hospital. Based on data collected from 603 participants, the most pertinent aspects of identity in the micro-level clinical encounter in Mumbai involve the following: age, gender, sex, social status, educational level, language, profession, ethnicity, and lifeworlds. Additionally, I provide data on how the emerging themes of physician synergy, ritual, medical record, and traditional remedies illustrate salient aspects of the Indian variant of Biomedicine. Furthermore, my findings suggest that the macro-level forces of Mumbai culture, healthscapes, hierarchy, globalization, and political economy of medicine directly impact the Mumbai healthcare context and its clinical encounters. This dissertation provides insights into how Biomedicine, a global force, is enacted in the local Indian context and illuminates pathways for doctors and patients in other clinical contexts to promote successful communication.

Clinical practice is an integral component in nursing education. Pre-qualified nurse learners are required to work in different clinical settings to develop their skills competency. Conducting clinical skills education has always been a challenge to nursing teachers in Hong Kong and worldwide. This study adopts a case study methodology using three data collection methods including individual interviews, a focus group interview and the researcher's participant observation experience in a clinical visit and her skills laboratory teaching during a 3-month class in the teaching programme. Alongside inviting nursing student participants, this study also utilised the insights of nursing teachers, clinical nurses, and advanced practice nurses. Drawing upon the ideas from Vygotsky's Sociocultural Theory, this study engages with several Vygotskian concepts such as: "learning from the more knowledgeable others", "social interaction", "scaffolding" and "zone of proximal development". Through the collection of multiple sources of data, this case study favours a critical inquiry of the sociocultural factors and their relation to clinical education. It uses thematic analysis, synthesizing the findings, identifying four overarching themes namely the environment related sources, human-related sources, culture-related sources, skills-teaching-related sources along with eight sub-overarching themes have been generated. The findings reflect the dilemmas existing in clinical nursing education and uncovers the nursing students as well as the practitioners managing intense pressures which significantly affect the delivery of clinical skills education. The research study fronts the complex sociocultural context which influences the students' learning and teachers' mentoring, and it offers an important insight into the challenges of conducting clinical nursing skills education.

This study explores the perception of nursing students using health technology during clinical training and examines the impact of health technology related to the Clinical Learning Environment (CLE). As there is an increasing demand for quality care from patients and the challenges posed by a high turnover rate of nurses, nurses struggle to work and adapt in this changeable setting. This study aims to develop an insight into an understanding of the CLE. It includes the perceptions of nursing students regarding health technology and the impact on their learning as nursing students. It uses a case study methodology, using a survey of the Clinical Learning Environment, Supervision and Nurse Teacher Scale (CLES+T) and interviews with nursing students, graduated nurses and academic university mentors. The study utilises the theoretical work of Kolb's learning process, behaviourism and constructionism learning theories, and a facilitation/supervision model. Findings suggest that nursing students lack practice opportunities. Further, additional factors relate to issues of leaderships, ward atmosphere, supervisory relationships, learning opportunities, and nurse teachers interwoven in a health technology integrated setting. Nursing students specifically reflected on their concerns about health technology dependency and how this potentially limits their critical thinking skills. Further still, limitations to access password integrated health technology restricted students' learning, their practice opportunities rely on a good supervisory relationship and a positive ward atmosphere. To some extent, students indicated that the managerial staff could shape the CLE and affect their learning opportunities regarding their supervision and mentoring. This study contributes to the emerging knowledge about the impact of health technology on the learning of nursing students in the clinical setting during training. It provides an understanding of the challenges posed by both health care providers and educational institutions who should coordinate more measures to facilitate students' learning in the health technology integrated CLE. This study helps to address the issues related to health technology in clinical settings and its impact on the practice of nurses including academic staff which, in turn, affect students' learning.