VictorJuiz/thesis huggingface dataset:
Optical, Electrical and Thermal Modelling of Nanoscale Plasmonic Devices
Keywords: Plasmonics
Modelling
Optics
Integrated
vanadium dioxide
VO2
surface plasmon polaritons
optical switch
nanoscale
numerical

The behaviour of surface plasmon polaritons (SPPs) in nanoscale geometries is studied using numerical methods supported by theory and experiment. First, we derive the behaviour of SPPs at graded metal-dielectric interfaces, including dispersion relations, field profiles, propagation velocities, losses, and cutoff wavelength. Numerical simulations show excellent agreement with analytic solutions. In the second part of the thesis we design hybrid vanadium dioxide-plasmonic based absorption switches. The switches are designed and optimized using optical, electrical and thermal simulations. 5 µm switch designs have extinction ratios exceeding 30 dB and require powers of 10 mW. A switch is fabricated based on the proposed design. A 7 µm experimental switch reaches 16.4 dB of extinction and requires 64 mW of power, making it one of the most efficient optical switches ever demonstrated in terms of extinction and power consumption. Numerical simulations predict experimental results with a high degree of accuracy.
Infants' Perception of Non-contrastive Variation
Keywords: Speech Perception
Infancy

Newborns were once viewed as having the ability to distinguish between all possible speech contrasts present in the world’s languages. However, recent work suggests that this view is an oversimplification of young infants’ perceptual abilities. This study used the Stimulus Alternation Preference Procedure (SAPP) to examine 6- and 10- month-old infants’ ability to discriminate between voiced and voiceless stops (lexically contrastive in English) as well as voiced and pre-voiced stops (not lexically contrastive in English). Six-month-olds distinguished between voiced and voiceless stops, but not between voiced and pre-voiced stops. Ten-month-olds failed to discriminate either contrast. We tentatively conclude that 1) pre-voicing may be a subtle contrast requiring experience to perceive, and 2) the SAPP might not be an ideal method to examine discrimination abilities in 10-month-olds.
Antifungal Efficacy of a Citrus Fruit Extract against Candida albicans Cells
Keywords: Candida albicans
Citrus
Antifungal
Biofilms

The number of superficial candidal infections has grown due to an increase in the elderly cohort and ever-increasing immunocompromised population, and the increased prevalence of antifungal drug resistance. The aim of this research was to investigate the antifungal efficacy of a citrus fruit extract, Biosecur c320c (B320), against two strains of Candida albicans (nystatin sensitive and resistant). The viability of C. albicans strain treated with 10% B320 was reduced by 90-99% depending on biofilm age. A B320/nystatin combination demonstrated even greater efficacy at killing biofilm cells in either strain. The nystatin sensitive strain did not develop resistance to B320 while resistance was developed following long-term exposure to nystatin. Scanning electron micrographs of C. albicans biofilms revealed cellular debris after treatment with combined B320/nystatin. Citrus fruit extracts containing polyphenols might contribute to the development of novel therapeutics for the treatment of oral candidiasis, particularly in those refractory to nystatin therapy.
Usability Study of Ambulatory Gait Analysis Prototypes
Keywords: Gait
User Centred Design
Usability
User Experience

The goal of this thesis was to explore the usability of on-foot sensors for ambulatory gait analysis. Using a human factors engineering approach, two different ambulatory gait analysis prototypes were assessed in two separate studies. The first study was conducted with student participants in a university setting and the second study was conducted in-situ with neurorehabilitation patients at Bridgepoint Hospital. The usability and patient experience of the prototypes were assessed, and based on these findings a set of recommendations was developed. These issues and recommendations are detailed in this thesis and are expected to inform the design of future iterations of the prototypes.
An Investigation of the Use of Hybrid Suspension-solution Feedstock to Fabricate Direct-oxidation Nickel-Based Anodes (BaO-Ni-YSZ, CeO2-Ni-YSZ, Sn-Ni-YSZ) by Plasma Spraying
Keywords: Solid Oxide Fuel Cell
SOFC
Direct Oxidation
Nickel Based Anodes
Plasma Spraying

The reduction of manufacturing costs and the facilitation of direct-oxidation of hydrocarbon fuels have been identified as means of promoting the commercialization of the solid oxide fuel cell, a technology that offers both environmental and fuel conservation benefits compared to conventional energy conversion technologies. This research was conducted with the aim of realizing the production of direct-oxidation anodes using atmospheric plasma spraying, which has been identified as a fabrication technique that has the potential to reduce the manufacturing costs of solid oxide fuel cells. This thesis details the rationale behind the selection of the anode compositions (BaO-Ni-YSZ, CeO2-Ni-YSZ, and Sn-Ni-YSZ) and the specifics of the specialized fabrication strategy (SPS-SPPS) that was devised with the aim of realizing microstructures similar to those where the secondary phases (BaO, CeO2, and Sn) coat the surfaces of the primary Ni and YSZ phases. Results of XRD, SEM and EDS analyses are presented.
The Influence of End Conditions on Vortex Shedding from a Circular Cylinder in Sub-critical Flow
Keywords: Aerospace
Flow Dynamics

The effect of end boundary conditions on the three-dimensionality of the vortex shedding from a circular cylinder in sub-critical flow has been studied experimentally, with a focus on the unsteady nature of the vortex filaments. Analysis of the near-wake of the cylinder was undertaken to determine the dependency of the spanwise uniformity of the vortex shedding on the end conditions. Flow visualization was performed downstream of the cylinder, and the temporal variation of the vortex filament angle was observed. Vortex dislocations were found to occur in this Reynolds Number regime regardless of the end boundary conditions. Having a cylinder bounded by two elliptical leading edge geometry endplates at an L/D value of five yielded parallel shedding with a reduction in the time-based variation of the vortex filament angle, and was shown to be the ideal end conditions for modeling an infinite cylinder in a free-surface water channel.
The Evolution of Soot Morphology in Laminar Co-flow Diffusion Flames of the Surrogates for Jet A-1 and a Synthetic Kerosene
Keywords: Soot morphology
Jet A-1 Surrogate
Kerosene
Laminar coflow diffusion flame
FT-SPK
GtL Surrogate

An experimental study was performed to study soot formation and evolution in atmospheric, laminar, coflow, diffusion flames of Jet-A1, Synthetic Paraffinic Kerosene and their surrogates. Light extinction, rapid thermocouple insertion and thermophoretic sampling followed by transmission electron microscopy and atomic forced microscopy were used to obtain soot volume fraction profiles, temperature profiles and soot morphologies, respectively. Different soot evolution processes were observed on the flame centerline and on a streamline with a significantly different temperature history. Formation and agglomeration of the first soot particles are different on the two streamlines. Transparent liquid-like particles are produced in large volumes in the early regions of the flame centerline where T < 1500 K; these particles are undetectable by the extinction method with the wavelength of 632.8 nm. Most of the currently used computational soot models do not predict the liquid-like nature of nascent soot particles which has major effects on the modeling.
Effect of Food Advertisements on Satiety and Meal-time Food Intake in 9-14 Year Old Boys and Girls
Keywords: Food advertisements
children
satiation
short term food intake
satiety
caloric compensation

The effect of meal-time exposure to food advertisements (FA) on food intake, subjective appetite and caloric compensation was investigated in overweight/obese (OW/OB) and normal weight (NW) boys (study 1) and girls (study 2). In random order, each participant watched either FA or non-food advertisements (NFA) 30 min after consumption of either a non-caloric sweetened control (CON) or a glucose (GLU) drink. Food advertisements increased food intake only in OW/OB girls. The GLU drink reduced food intake in both girls and boys despite no changes in subjective appetite. Food advertisements did not modify the response to the GLU drink in girls and contrary to the hypothesis they magnified the reduction in energy intake following the GLU drink in boys. In conclusion, FA in a TV program during consumption of a pizza meal by NW and OW/OB boys and girls increased food intake only in OW/OB girls and increased caloric compensation for the GLU drink at meal time in boys but not in girls.
Efficiency and Emissions Study of a Residential Micro-cogeneration System based on a Modified Stirling Engine and Fuelled by a Wood Derived Fas Pyrolysis Liquid-ethanol Blend
Keywords: Stirling engine
bio-oil
fast pyrolysis liquid

A residential micro-cogeneration system based on a Stirling engine unit was modified to operate with wood derived fast pyrolysis liquid (bio-oil)-ethanol blend. A pilot stabilized swirl combustion chamber was designed to replace the original evaporative burner due to bio-oil’s nondistillable nature. This also required modifications of the engine’s control systems. Efficiencies for the bio-oil/ethanol blend were found be higher than those of diesel due to the higher heat loss incurred with diesel. Based on a modified efficiency, which disregarded the heat loss through the combustion chamber, power efficiencies were found to be comparable. The maximum time of operation with the bio-oil/ethanol blend was approximately 97 minutes due to the clogging of the narrow passages. Carbon monoxide emissions were higher for the bio-oil/ethanol blend due to the operation conditions of the combustion chamber. Oxides of nitrogen emissions were also higher for the bio-oil/ethanol blend due to its inherent nitrogen content.
Modeling and Robust Control Design for Distributed Maximum Power Point Tracking in Photovoltaic Systems
Keywords: distributed maximum power point tracking
power electronics
control for power electronics
photovoltaic (PV) systems
micro-converters
linear matrix inequalities
system modeling
compensator design

Photovoltaic installations in urban areas operate under uneven lighting conditions. For such a system to achieve its peak efficiency, each solar panel is connected in series through a micro-converter, a dc-dc converter that performs per-panel distributed maximum power point tracking (DMPPT). The objective of this thesis is to design a compensator for the DMPPT micro-converter. A novel, systematic approach to plant modeling is presented for this system, together with a framework for characterizing the plant’s uncertainty. A robust control design procedure based on linear matrix inequalities is then proposed, which ensures robust performance and stability of the time-varying system. The proposed modeling and control design methods are demonstrated for an example rooftop photovoltaic installation. The system and the designed compensator are tested in simulations. Simulation results show satisfactory performance over a range of operating conditions, and the simulated system is shown to track the maximum power point of every panel.
Gene Patents and Access to Genetic Diagnostic Tests
Keywords: Gene Patents
Diagnostic Tests
Innovation
Intellectual Property
IP law
Invention

The utilitarian theory contemplates rewarding the risks of inventors by providing them with a defined period of exclusivity to recoup their investment. For inventions requiring further investment, patents enable the creation of financial relationships between inventors and investors by providing patent exclusivity during the commercialization process. Innovation, contrasted from invention and conceptualized as commercialization, however, does not necessarily form the best means for delivering to the public inventions intended to improve health. Although patent policy conflates the economic growth and health improvement objectives of innovation, these goals do not always align. While the exercise of BRCA patents instantiates exclusive practicing of patents that failed to adequately deliver health technology, the patent system does not need significant change. Rather, to maintain the expectations of patent holders while balancing the needs of the public, current practices should continue with the encouragement of the creation of voluntary patent pools.
The Design and Evaluation of an Interactive Musical Staircase on Physical Rehabilitation Therapies for Children
Keywords: rehabilitation
physical therapy
audio biofeedback
gait analysis

Stair-climbing is an important skill for promoting independence and activities of daily life and is a key component of rehabilitation therapies for physically disabled children. This thesis describes the design and evaluation of an interactive musical stairs system for children engaged in stair-climbing physical therapies. The achievement of a targeted therapeutic goal, namely, use of reciprocal steps, was significantly increased by 6% [SD=7%] (p=0.007) with the presence of audio feedback. Levels of participant enjoyment and motivation increased as well. This led to the development of an automated system, using inertial sensors to detect initial contact (IC) events each time a child makes a step, to trigger audio feedback. A semi-generic algorithm was designed that was able to detect 96% [SD=3%] of IC events during stair-climbing therapy sessions. This thesis lays the groundwork for future longitudinal research investigating the efficacy of audio feedback in stair-climbing and other rehabilitation therapies as well.
Broadband Microwave Negative Group Delay Transmission Line Phase Shifters
Keywords: transmission line
phase shifter
negative group delay
group delay

The analysis and design of passive broadband negative group delay (NGD) transmission line phase shifters is presented. By extending the metamaterial transmission line concept to include loss, a NGD unit cell is proposed. Phase shifters are supplemented with NGD unit cells to produce a flattened phase response significantly increasing phase bandwidths. The design methodology of a NGD phase shifter is presented with consideration of nominal phase, frequency, impedance, maximum insertion loss and bandwidth. The relation between gain, bandwidth and group delay signifies a fundamental design limitation and tradeoff. A significant application of NGD phase shifters for removing beam squint in series fed antenna arrays is discussed. Several NGD phase shifters are fabricated and experimentally verified in the UHF band upwards of 1 GHz using planar microstrip transmission lines loaded with passive surface mount RF components with both positive and negative phase shifts.
Traditional Knowledge in the Manacles of Intellectual Property Protection - A Study of Indian Indigenous Communities’ Rights and Claims
Keywords: Traditioanl Knowledge
Medicinal Knowledge

The present thesis focuses on Indian experience in the traditional knowledge sector. It argues that strong patent protection has not been conducive to the indigenous people and their traditional medicinal knowledge. Moreover, this protection has supported the pharmaceutical sector by entitling it with the patents, sourced from traditional herbal medicinal knowledge on the ground of novelty and usefulness. The thesis also investigates the scenarios, where time and again it has been proved that the current patent tool does not provide free hand to indigenous people. It advocates that the production and dissemination of legal clauses promoted by the Indian patent system is not an adequate legal tool for the protection of traditional medicinal knowledge. Finally the thesis explores India’s obligation to protect and preserve traditional medicinal knowledge and proposes model guidelines for the pharmaceutical sector in order to exploit herbal medicinal knowledge.
Development of a Microfluidic Platform to Investigate Effect of Dissolved Gases on Small Blood Vessel Function
Keywords: microfluidic
dissolved gas
resistance artery
microvasculature
hypoxia
PDMS
oxygen sensing
PtOEPK

In this thesis I present a microfluidic platform developed to control dissolved gases and monitor dissolved oxygen concentrations within the microenvironment of isolated small blood vessels. Dissolved gas concentrations are controlled via permeation through the device substrate material using a 3D network of gas and liquid channels. Dissolved oxygen concentrations are measured on-chip via fluorescence quenching of an oxygen sensitive probe embedded in the device. Dissolved oxygen control was validated using the on-chip sensors as well as a 3D computational model. The platform was used in a series of preliminary experiments using olfactory resistance arteries from the mouse cerebral vascular bed. The presented platform provides the unique opportunity to control dissolved oxygen concentrations at high temporal resolutions (<1 min) and monitor dissolved oxygen concentrations in the microenvironment surrounding isolated blood vessels.
Oxidative Stress and the Risk of Osteoporosis: The Role of Dietary Polyphenols and Nutritional Supplements in Postmenopausal Women
Keywords: Oxidative stress
Osteoporosis
Postemenopausal women
Polyphenols
Antioxidants
Reactive oxygen species

Previous findings have indicated that oxidative stress plays a role in the development of osteoporosis and that individual polyphenols, by virtue of their antioxidant properties, may mitigate these damaging effects. Nutritional supplements, greens+ bone builderTM, containing polyphenols and other micronutrients beneficial for bone health are of recent interest as complementary strategies in the management of osteoporosis. A randomized controlled study was conducted to explore the combined effects of the nutrients found within the supplement on bone health for 8 weeks. Total polyphenol content and antioxidant capacity increased whereas oxidative stress parameters and the bone resorption marker, crosslinked C-telopeptide of type I collagen decreased after supplementation. There was no significant change in the bone formation marker, procollagen type I N-terminal propeptide. This thesis shows an association of polyphenols with other micronutrients acts through their antioxidant capacity to decrease oxidative stress parameters and bone resorption, thus potentially reducing the risk for osteoporosis.
Label-free Target Nucleic Acid Detection using a Quantum Dot-FRET based Displacement Assay
Keywords: Quantum dot
Fluorescence resonance energy transfer

The exploration of a quantum dot fluorescence resonance energy transfer (QD-FRET) based bioassay for label-free target nucleic acid detection is reported herein. This work explores the potential for developing a displacement assay for detection of nucleic acid sequences of various lengths, including one of 484 bases. Short probe oligonucleotides conjugated to QDs were allowed to hybridize to short partially mismatched dye-labelled oligonucleotide targets. The non-labelled target of interest, a 484-base segment of heat shock protein 70 (HSP 70), contained a portion that was fully complementary to the probe. Thermodynamic parameters suggested that HSP 70 would displace dye-labelled targets; however, detection was not observed. Modifications were made to this assay to reduce sterics and increase the stability of hybrids. The results obtained using this modified assay indicated that detection of non-labelled, long oligonucleotide sequences was possible using a displacement assay that relied on a short probe oligonucleotide.
The Long March of Village Democracy: A Survey of the Progress toward Democratic Village Self-governance in China
Keywords: China
Democracy

Over the past 30 years, the Chinese policy of village self-governance has promoted a system of democratically elected autonomous committees to wield authority at the village level. Particularly in the period since 1998, the village committee system has made impressive achievements in most areas of electoral rules and procedures. Relatively free and fair elections have become commonplace throughout much of the Chinese countryside, and the level of competition and openness has gradually increased. Nonetheless, village self-governance has had only a modest impact on the actual political configuration of most villages, as Communist Party influence and state-imposed constraints have limited the ability of elected officials to exercise authority independently. It is hoped that future Chinese leaders will continue to strengthen the institutional framework of democratic village governance, and take steps to restrain the influence of non-democratic actors.
Does Human Leukocyte Antigen-G (HLA-G) Play a Role in Immunte Modulation and Vasculopathy in Heart Transplantation?
Keywords: HLA-G
transplantation
cardiac
immunology

HLA-G is a protein normally expressed during pregnancy, protecting the fetus from the maternal immune system. Previous studies have shown an association between HLA-G expression post-transplantation and lower incidences of organ rejection. To further examine this beneficial role, we conducted a prospective study following a cohort of heart transplant recipients for one year and measuring their plasma HLA-G levels at various time points. Preliminary analyses failed to reveal an association between HLA-G and various parameters of rejection and vasculopathy. However, we decided to examine the in vitro effects of HLA-G in a smooth muscle cell (SMC) migration assay and whether HLA-G can be modulated pharmacologically. We made the novel observations that purified HLA-G was capable of inhibiting migration of SMCs, a key event in the development of cardiac allograft vasculopathy. IL-10, an anti-inflammatory cytokine, was capable of upregulating HLA-G in a Jeg-3 cell line. The modulation of HLA-G may represent a strategy to protect again vasculopathy, which is a leading cause of morbidity and mortality in heart transplant recipients.
Harmonization of International Securities Markets Regulation: A Trade Perspective
Keywords: harmonization
securities
hybrid model
trade perspective
securities regulation
international securities
regulatory competition
World Trade Organization
General Agreement on Trade in Services
GATS
WTO
trade liberalization
mutual recognition
systemic risk
issuer choice
portable reciprocity
Tiebout
investor
systemic risk
negative externalities
multi-jurisdictional disclosure system
passport system
economies of scale
IOSCO
allocational efficiency
information cost
investor protection

Widespread cross-border securities trading have led to the internationalization of securities markets. No one seriously disputes that such securities dealings require regulation, but there is no academic consensus on the best normative approach to such regulation. The academic debate initially focused on whether regulatory competition or cooperation constitutes the better model. However, the debate seems to have evolved to adopt a hybrid model combining the virtues of these two approaches. ‘Harmonization’ constitutes the dominant hybrid model. Nevertheless, the implementation of the harmonization model has barely received any attention in the literature. The aim of this thesis is hence two-fold: first, justify why harmonization should be the preferred model for the regulation of international securities markets; and second, develop, applying an international trade regulation perspective, a regulatory framework to implement the harmonization model using the World Trade Organization and General Agreement on Trade in Services (WTO/GATS) framework.