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Research presented in this thesis was driven by the need to inform our current knowledge on Quality of life (QoL) of patients undergoing extensive surgery for advanced ovarian cancer. National Institute for Health and Care Excellence (NICE) commissioned this multicentre prospective observational research to update Interventional Procedure Guideline. Existing evidence supports the utilisation of extensive surgery to achieve complete debulking to improve survival outcomes. The systematic review found no good quality studies to inform QoL outcomes for extensive surgery. The observational study showed significant variation in case selection and surgical intervention across participating centres and patients undergoing extensive surgeries did not report a worse QoL compared to patients having less extensive surgeries. A specific investigation into incidence of acute kidney injury (AKI) as a parallel project showed overall incidence of AKI during treatment of advanced ovarian cancer is high (30%), however, most of these incidences were transient, related to patient's pre-existing co-morbidities and did not cause major deleterious effect on health within the study period. The result will inform the policy makers, organisations, clinicians and patients and should reassure them regarding use of extensive surgery in advanced ovarian cancer.

The aim of this project is to design, synthesise and characterise s-triazine based carbon nitride materials that show potential for use as fully renewable, organic photocatalyst materials for the purpose of generating hydrogen fuel through water splitting. Whilst existing materials do exist that can perform this technique, the inorganic constituents of these existing materials prevent them from being fully renewable and, in most situations, makes them difficult to synthesise - especially at room temperatures and ambient pressures. The method used in this project to improve upon existing organic photocatalyst materials was to develop more efficient techniques to create covalent organic structures that retain the structural benefits of graphene whilst including electrical storage properties recorded for nitrogen-doped graphene, in the form of an s-triazine structure. This was achieved by first focussing on improving the existing most efficient s-triazine based carbon nitride synthesis approach, polycondensation Ionothermal synthesis, by improving its output efficiency and then later adapting the technique so it could be implemented into existing industrial applications more effectively. Improvement of the existing technique was achieved through the use of a dynamic vacuum, with the graphitic carbon nitride material confirmed through XPS, XRD, FTIR and other characterisation techniques, the adaptation of the technique to make it more industrially useful was achieved through incremental development of the Ionothermal synthesis approach. This transition resulted in the creation of an ALD-type approach, which resulted in carbon nitride films (characterised by XPS, XRD, ATR-IR, Raman spectroscopy and various microscopy techniques) conformally coating onto a variety of substrates at room temperature. Whilst the synthesis reaction mechanism was determined to be different to those found in existing literature, through gas-phase mass spectrometry, various experimental parameters ranging from: synthesis temperature, ramp rate of temperature, ion gun depth profiling and others were determined to allow for precise control of the carbon nitride film formed with regards to its physical and chemical properties. As a consequence of this control, not only did the carbon nitride films show promise as potential photocatalyst materials, but they also showed promise as anti-microbial surfaces and could be used in the development of an XAES based D-parameter technique to determine the content of sp2 and sp3 nitrogen in a pure carbon nitride based material, composed of only sp2 and sp3 carbon and nitrogen. Finally, the usefulness of the s-triazine component for photocatalyst applications was also presented through the synthesis and characterisation of a phenolic triazine framework which is structurally like graphitic carbon nitride but contains a phenolic group that allows for a much more tuneable band gap. From the results of this project, evidence of the use, or potential use, of pure organic materials has been shown for several applications in addition to photocatalytic water splitting. However, unlike existing synthesis techniques, the vapour deposition technique developed in this project has demonstrated the potential of the organic materials to coat conformally onto a variety of substrates thus allowing for easy synthesis of carbon nitride based hybrid materials - thus compensating for the slightly lower efficiencies measured by the pure organic materials in comparison to purely inorganic structures.

Students struggle with proving, a fundamental activity in upper-level undergraduate mathematics courses. Learning how to prove is a difficult transition for students, as they shift from largely computation-based to argument-based work. In response, mathematics departments have instituted courses, introduction or transition to proof, designed to help students learn how to prove. Existing research has extensively examined students' errors, struggles, and some of their strategies at a given point in time, but we know little about students' development over a longer period of time. There is a need for longitudinal work in this area, to follow students through the transition to proof. In addition, little is known about the affective side of proving (e.g., attitudes, beliefs, emotions). Affect plays a central role in mathematics learning, influencing students' cognitive processes while problem solving and their motivation to value and want to do mathematics. Understanding affective issues are important, as students consider their future participation in mathematical work and communities. Positive experiences at transitional junctions, such as learning how to prove, are crucial for retention of students through the STEM (Science, Technology, Engineering, and Mathematics) pipeline. The purpose of this work was to explore the cognitive and affective factors involved in undergraduates' efforts to learn how to prove: how their proving developed during a transition to proof course and what kinds of "satisfying moments," i.e. positive emotional reactions, they experienced. Four semi-structured interviews across a semester were conducted with eleven undergraduate students enrolled in a transition to proof course. The resulting data was analyzed using qualitative methods. Findings indicate that students showed growth in fluency, strategy use, and monitoring and judgement over time. Four developments were frequently observed across the sample: (1) increased sophistication in students' rationales for choice of proof techniques, (2) awareness about how a solution attempt was going and managing that for their subsequent strategies, (3) intentional exploring and monitoring when unsure about what direction to pursue, and (4) checking examples in conjunction with other strategies as a way to become unstuck. The variety of developments--and the different ways in which they emerged--is significant, because it confirms that multiple developments occur in different ways, strongly suggesting that there is no one path that students take through the transition to proof. Students' satisfying moments were largely about accomplishments both with and without struggle, understanding, external validation, as well as interacting with others. A theory for how satisfying moments are elicited was proposed. Expectations and a sense of mastery played large roles in mediating satisfying moments, but students' desire for understanding and sense-making was also prominent. This work provides guidance for curriculum design of transition to proof courses, in considering how to support students' development in proving. In addition, examination of just what makes a satisfying moment satisfying is helpful in thinking about how to construct mathematical tasks with opportunities for positive experiences with math. [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 physiological response to excessively strong aversive stimuli – the stress response – is relatively maladaptive and leads to various psychopathologies such as anxiety disorders only in a minority of individuals. Our lab has previously shown that severe acute restraint stress heightens anxiety-like behaviour in wild-type but not in the extracellular serine protease, neuropsin, deficient mice. Dissecting molecular changes underlying genotypic differences, our microarray and qRT-PCR approaches revealed that the stress-induced upregulation of glucocorticoid receptor (GR) co-chaperone, Fkbp5, expression in the amygdala is significantly attenuated in neuropsin-/- mice compared to the wild-type mice and attenuated expression can be restored by bilateral intraamygdala injection of recombinant neuropsin. Further, blocking neuropsin cleavage of EphB2 with anti-EphB2 antibody suppressed only neuropsin-mediated but not corticosterone-driven upregulation of Fkbp5 expression in primary amygdala cultures unraveling novel neuropsin-dependent mechanism acting in synergy with the well characterized corticosterone pathway to mediate the robust stress-effect on Fkbp5 expression. Importantly, wild-type mice lacking amygdala specific Fkbp5 exhibit stress protective phenotype in unconditioned anxiety tests. Therefore, this study characterizes and concludes an indispensable role of amygdalar Fkbp5 in stressful episodes developing into anxiety disorders.

Digital imaging has seen an enormous growth in the last decade. Today users have numerous choices in creating, accessing, and viewing digital image/video content. Color management is important to ensure consistent visual experience across imaging systems. This is typically achieved using color profiles. In this thesis we identify the limitations of profile-based color management systems and propose an alternative system based on display device models and look-up tables (LUT). We identify techniques to design LUTs which are optimal in terms of color reproduction accuracy under resource constraints. We show that a LUT-based color management system is more accurate and memory-efficient than a comparable ICC profile-based system. Visual surveillance is often used for security and law enforcement applications. In most cases the video data is either passively recorded for forensic applications or is remotely monitored by human operators. We propose the use of image and video analysis techniques to assist the operators. This would reduce human errors due to fatigue, boredom, and excess information. We describe a video surveillance system to observe vehicular traffic from a standoff range and detect anomalous behavior by analyzing the motion trajectories. We also extract physical information (such as make, tire size, and body type) which can help determine the "normal" behavior. The operator can also use this information to uniquely identify/describe individual vehicles. We describe low complexity techniques to perform the above analyses and show their effectiveness on real traffic videos. [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.]

In this study, the unsteady, turbulent flow over NACA 0015 was analyzed using synthetic jets. The study focused on applying the numerical method using the commercial CFD solver Ansys Fluent. The synthetic jet simulation was carried out for Re = 896,000 for two angles of attack: 10 and 14 degrees. The optimal jet amplitude and jet frequency were determined from a range of amplitudes of 2.0 to 4.0 and frequencies of 0.4 Hz to 1.2 Hz while the jet location, jet angle, and jet width were fixed. The results showed that for both angles, the optimal amplitude and frequency were 4.0 and 0.8 Hz, respectively. As the amplitude increased, the lift-to-drag ratio went up, and the variance in frequency did not impact the aerodynamic coefficients much. The flow separation was observed at various instances for the synthetic jet which showed that when suction was applied the separation was delayed, and the opposite was true for injection. On average, the separation was delayed for both angles with the use of a synthetic jet. Additionally, the impact of steady injection and suction jets was examined. The results were similar to before where the injection jet did not improve the force characteristics, but suppression increased the lift-to-drag ratio by 53.91\% for the 10-degree case and 42.40\% for the 14-degree case. The separation location remained the same for the injection jet at 10 degrees, but with the suction jet, the flow did not separate. In the post-stall angle case, both steady injection and suction delayed separation.

The bottom-up generation of lipid membranes from minimal precursors is a key objective in synthetic biology research. In living cells, the synthesis of lipid assemblies is ubiquitously coordinated by several membrane-bound enzymes. However, these pathways are tough to replicate, owing to the difficulty of reconstituting the enzymes in vitro. Lipid membrane synthesis from simple metabolic building blocks remains challenging. We demonstrate a chemoenzymatic schematic for lipid membrane generation, utilizing a bacterial fatty acid synthase (cgFAS I) to synthesize palmitoyl-CoA in situ from acetyl-CoA and malonyl-CoA as precursors. Palmitoyl-CoA spontaneously reacts with a cysteine-modified lysophospholipid via native chemical ligation (NCL), generating noncanonical amidophospholipids that self-assemble into micron-sized membranes. The results demonstrate that combining the specificity and efficiency of a type I fatty acid synthase with a selective bioconjugation reaction provides a biomimetic route for the de novo formation of membrane-bound vesicles. Utilizing this route, we further investigate the application of non-amphiphilic, minimal precursor pathway to generate lipid membranes. We explore the use of acetate as the carbon feedstock for the chemoenzymatic reaction strategy, generation palmitoyl-CoA in situ and coupling it with small molecule head group such as cysteine to form phospholipid analogs. Ubiquitous enzymes acetyl-CoA synthetase (ACS) from E. coli was used to generate acetyl-CoA from acetate and human acetyl-CoA carboxylase (ACC) was used to then synthesize malonyl-CoA from acetyl-CoA. Additionally, cgFAS catalyzed the in situ generation of palmitoyl-CoA from acetyl-CoA and malonyl-CoA. Finally, we explore the formation of a unique analog of sphingolipid membranes from water-soluble precursors that have markedly different biophysical properties to their natural counterparts. We show that numerous transition metal ions, particularly Cu(II), catalyze the selective O-acylation of the biologically occurring single-chain amphiphile sphingosylphosphorylcholine using fatty acyl phosphates or thioesters as acyl donors under mild aqueous conditions. This work demonstrates the value of de novo membrane generation strategies starting from minimal, water-soluble precursors. Utilizing such approaches, we can control both the chemical structures of the lipid analogs as well as their biophysical properties in aqueous media. This effort contributes towards understanding the fundamental requirements for bottom-up generation of lipid membranes, providing alternative strategies to those previously shown.

Hundreds of millions of people around the world are exposed to toxic levels of arsenic dissolved in the groundwater they use for drinking. Low income communities are disproportionately affected by this arsenic poisoning because they lack the necessary technical, managerial, and financial capacity to address the issue. Iron electrocoagulation (FeEC) holds promise to address arsenic contamination in such resource-constrained communities because it relies on locally available materials, a minimal supply chain and low operating costs. This dissertation builds upon an ongoing demonstration of a community scale FeEC plant in West Bengal, India, that has been supplying arsenic safe water to the local community at an affordable price since 2016. This dissertation underpins three main objectives in detail. First, it analyzes the causation behind surface layer growth or passivation of large (1000 mm × 900 mm × 3 mm) Fe(0) electrodes in active use for more than two years. Second, with an aim to develop a compact, rapid and an effective arsenic treatment solution, it advances the standard FeEC to a more effective version, Air Cathode Assisted Iron Electrocoagulation (ACAIE). This study compares arsenic removal efficacies and mechanisms of FeEC and ACAIE over a range of operating conditions varying over an order of magnitude. Third, to assess the practical feasibility of ACAIE, its long-term performance is investigated. A particular emphasis is laid on fouling of the air cathode and its impact on H2O2 generation, and thus on the ability to achieve contaminant removal. In FeEC, a commonly noted limitation is the passivation of electrode surfaces via rust accumulation over long-term use. In Chapter 2, we characterized the surface layers formed on the electrode plates and examined the effect of surface layer removal, on the performance of an FeEC plant in India. The electrode surfaces developed three distinct horizontal sections of layers that consisted of different minerals: calcite, Fe(III) precipitates and magnetite near the top, magnetite in the middle, and Fe(III) precipitates and magnetite near the bottom. The interior of all surface layers adjacent to the Fe(0) metal was dominated by magnetite. After removing the surface layers by mechanical cleaning, substantial improvements both in the Fe concentration in the bulk solution, and removal rates of As, P and Si, were observed. Results presented in this chapter show that removing surface layers that accumulate on electrodes over extended periods of operation can restore FeEC system efficiency (mass of solute removed/kWh delivered). Therefore, these findings assert that routine electrode maintenance can ensure robust and reliable FeEC performance over year-long timescales. However, routine (e.g. daily) electrode maintenance may not be feasible in regions (e.g. rural California) where labor costs are high. Also, FeEC requires long operating times (~hours) and a relatively large footprint to remove dissolved arsenic due to inherent kinetics limitations. In response to these limitations, ACAIE was developed, with an aim to provide a compact, rapid and an effective arsenic treatment solution. In Chapter 3, the arsenic removal efficiency of FeEC and ACAIE are compared for a range of operating parameters (electrolysis times: 0.5 to 200 minutes, charge dosage rates: 1.5 to 1200 C/L/min, current densities: 0.8 to 156 mA/cm2) for removing As(III) from an initial concentration of ~1500 μg/L in synthetic groundwater. ACAIE consistently outperformed FeEC in bringing arsenic levels to less than World Health Organization (WHO) maximum contaminant level (MCL) of 10 μg/L. X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) analysis conclusively showed that poor arsenic removal in FeEC arises from incomplete As(III) oxidation, incomplete Fe(II) oxidation and the formation of Fe(II–III) (hydr)oxides at short electrolysis times (

Contact fatigue failure has been in research since the early twentieth century. The need for a second generation sliding-rolling contact fatigue tester was proposed by Gregory Dvorak and Dr. Marcellin Zahui. The first generation RCF tester was used for testing super finishing processes for gear surfaces. The second generation RCF tester was funded by the Advanced Engineering Materials lab of University of North Dakota. Verification of the second generation Rolling Contact Fatigue Tester will be discussed in this thesis including the design details, assembly and testing procedure and to discuss its different parameters. The tester will have the capability of testing hollow specimens using a bobbin eddy current testing probe. This tester will allow a wide range of experiments and is not built for one specific purpose. An eddy current device is used for detecting cracks. The loading force is applied using hydraulic cylinders and a hydraulic power unit. Before testing began, the machine was run for some time at full speed. A lot of minor problems were detected and fixed. Three specimens of AISI 8620 were tested in this tester. All tests gave results matching with some of the other well-known RCF testers. These tests were performed to evaluate mechanical limits of the tester and to evaluate the software performance of the tester.

We extend the Jinni mobile agent architecture with a multicast network transport layer, an agent-to-agent delegation mechanism and a reflection based Prolog-to-Java interface. To ensure that our agent infrastructure runs efficiently, independently of router-level multicast support, we describe a blackboard based algorithm for locating a randomly roaming agent. As part of the agent-to-agent delegation mechanism, we describe an alternative to code-fetching mechanism for stronger mobility of mobile agents with less network overhead. In the context of direct and reflection based extension mechanisms for Jinni, we describe the design and the implementation of a reflection based Prolog-to-Java interface. The presence of subtyping and method overloading makes finding the most specific method corresponding to a Prolog call pattern fairly difficult. We describe a run-time algorithm which provides accurate handling of overloaded methods beyond Java's reflection package's limitations.