VictorJuiz/thesis huggingface dataset:
Silicon Refining Through Chemical Vapor Deposition

Currently the cost of solar grade silicon accounts for approximately one third of the total solar cell cost, therefore a new silicon refining process is being proposed with the goal of lowering the cost of producing solar grade silicon. In this new process, Si-Cu alloys were used as the silicon source. One to one molar ratio H2-HCl gas mixtures were used as transport agents to extract Si out from the Si-Cu alloy at about 300-700oC, with following reaction taking place: Si+3HCl(g)=HSiCl3(g)+H2(g) While at about 1000-1300oC, pure Si deposits onto a hot silicon rod according to: Si+3HCl(g)=HSiCl3(g)+H2(g) The role of the copper in the alloy was to trap impurities in the Si and catalyze the gas solid reaction. A study on determining the rate limiting step and impurity behavior was done. A possible silicon extraction reaction mechanism was also addressed.

Keywords: Solar Silicon
Chemical Vapor Deposition
Silicon Refining
Advisor: Utigard, Torstein A.
Hydraulophones: Acoustic Musical Instruments and Expressive User Interfaces

Fluid flow creates an expansive range of acoustic possibilities, particularly in the case of water, which has unique turbulence and vortex shedding properties as compared with the air of ordinary wind instruments. Sound from water flow is explained with reference to a new class of musical instruments, hydraulophones, in which oscillation originates directly from matter in its liquid state. Several hydraulophones which were realized in practical form are described. A unique user-interface consisting of a row of water jets is presented, in terms of its expressiveness, tactility, responsiveness to derivatives and integrals of displacement, and in terms of the direct physical interaction between a user and the physical process of sound production. Signal processing algorithms are introduced, which extract further information from turbulent water flow, for industrial applications as well as musical applications.

Keywords: hydraulophone
acoustics
liquid
state of matter
water
oscillation
hydraulophonic
sound production
karmanizer
turbulence
Von Karman
vortex
Poiseuille
Embouchure
user interface
expressivity
suite for hydraulophone
composition
absement
presement
musical instruments
underwater
hydrophone
jet
Particle Rejection Theory
0986
0413
Advisor: Mann, Steve
Structural Effects of Photodynamic Therapy and Bisphosphonates on Healthy and Metastatically Involved Vertebral Bone

The vertebral column is the most common site of skeletal metastatic development secondary to breast cancer. Multiple clinical treatments are available for spinal metastasis, including systemic bisphosphonates and radiation therapy, however the success of current treatment approaches varies considerably. Alternative treatment strategies for spinal metastatic destruction must be aimed at both reducing tumor burden and restoring mechanical stability. Photodynamic therapy (PDT) has been shown to be successful at destroying osteolytic lesions in preclinical models of breast cancer spinal metastasis. However, the clinical feasibility of PDT for spinal metastasis is dependent on its potential effects on the structural integrity of vertebral bone. This thesis aims to determine the effects of PDT alone and in combination with bisphosphonate therapy on the structural architecture and mechanical properties of healthy and metastatically involved vertebrae. PDT was shown to have a positive effect on vertebral bone structure, alone and in combination with previous bisphosphonate therapy.

Keywords: photodynamic therapy
spinal metastasis
Advisor: Whyne, Cari
Molecular Identification and Physiological Characterization of Alternative Oxidase Gene Family Members in Nicotiana tabacum

Two projects were undertaken to study the non-energy conserving alternative pathway present in the plant mitochondrial ETC. In the first project, a tobacco AOX2 gene was cloned and characterized. AOX2 showed tissue specificity in expression and could not be induced by common stresses. In the second project I carried out a physiological characterization of transgenic tobacco plants with increased or decreased expression of AOX1 subjected to cold stress. Under non-stress condition, a strong inverse relationship between levels of AOX1 and levels of oxidative damage was observed, while after cold treatment AOX1 transgenic lines and WT showed more complicated and differential responses in aspects of oxidative damage and the capacity of antioxidant system. I also discovered that the pool sizes of monosaccharides after temperature shift were proportional to AOX1 levels. These results indicated that AOX1 might have crucial but complex impacts on ROS balance and carbon metabolism during cold stress.

Keywords: Plant physiology
Molecular biology
Alternative oxidase
Reactive oxygen species
Advisor: Vanlerberghe, Greg
Discovery and Characterization of Microbial Esterases for Fiber Modification

Carboxyl esterases, particularly arylesterases, were predicted from 16 microbial genomes, and then expressed in E. coli. Of the more than 175 cloned genes, 86 were expressed in soluble form. These were screened for activity using a range of both commercial and natural substrates. Forty-eight proteins were active on pNP-acetate at pH 8 whereas 38 proteins did not exhibit any activity towards any substrates. Among the 48 active proteins, 20 proteins showed arylesterase activity. To date, 8 bacterial esterases and 2 archaeal arylesterases were characterized in terms of pH stability and optima, thermal inactivation, solvent stability, and kinetics. To our knowledge there is only one other published report of arylesterases from archaea. The synthetic capability of arylesterases can transform phenolic acids to value-added chemicals. Accordingly, this project provides an arsenal of industrially significant activities that can extend the antioxidant properties of lignin-derived molecules in a broader range of renewable products.

Keywords: microbial esterases
enzymatic assays
Advisor: Master, Emma
Upregulation of VEGF-A using Engineered Zinc Finger Protein Gene Therapy Increases Cell Survival After Lateral Fluid Percussion Injury in Rats

Vascular endothelial growth factor (VEGF) may play a role in neuroprotection after traumatic brain injury (TBI) in addition to being a regulator of angiogenesis. Gene therapy using an adenovirus carrying an engineered zinc-finger protein (Adv-ZFP) and transcription factor construct targeted to the VEGF gene, has been shown to upregulate genomic expression of VEGF-A isoforms in skeletal muscle. Our objective was to use this gene therapy to explore cell survival in TBI. Rats were subjected to a unilateral fluid percussion injury (FPI) in the cortex. Groups consisted of control, injured and injured-treated animals. Adv-ZFP-VEGF was injected into the cortex and hippocampus. Engineered ZFP-VEGF increases VEGF-A protein levels and correlates with increased CA2 hippocampal cell survival and reduction in apoptotic cell death following TBI. NF200 expression in TBI+VEGF animals was comparable to levels in naive animals. This study suggests a therapeutic strategy to treat delayed cell death in a model of TBI.

Keywords: Traumatic Brain Injury
VEGF
Advisor: Baker, Andrew
Initial Flare Symptoms Resulting from Use of LHRH Agonist in Metastatic Prostate Cancer: Systematic Review and Economic Evaluation

Background LHRH agonists decrease tumour size/activity by suppressing testosterone in prostate cancer; however, initial injection causes testosterone surge that triggers flare symptoms. Anti-androgen given with agonist may reduce/avoid flare symptoms. When LHRH antagonist/blocker is introduced, testosterone suppression is immediate, but there is uncertainty about significance of flare symptoms without anti-androgen. Objective Systematic review compared significance of flare symptoms avoided and cost utility analysis using modelling comparing incremental value of blocker (degarelix) OR agonist (goserelin)+anti-androgen (bicalutamide) VERSUS agonist alone in prostate cancer patients. Outcome Incremental cost/QALY of bone pain as flare symptom between treatments Results Thirteen studies were reviewed. There was no standard definition for flare symptoms or data on LHRH antagonist versus other treatments on flare. From societal perspective, goserelin+bicalutamide was dominated over goserelin alone and similarly, from public perspective, goserelin+bicalutamide had favourable cost effectiveness profile against goserelin. Conclusion With bone pain as clinical endpoint, LHRH agonist+anti-androgen had favourable cost-effectiveness profile compared to goserelin.

Keywords: prostate cancer
LHRH agonist
Advisor: Nauenberg, Eric
A Series-parallel Resonant Converter for Electrochemical Wastewater Treatment

Advantages of electrochemical wastewater treatment over conventional wastewater treatment include its smaller footprint, modularity, and ability to meet increasingly stringent government regulations. A power supply that can be packaged with an electrochemical stack could make electrochemical wastewater treatment more cost-effective and scalable. For this application, the series and series-parallel resonant converters are suitable power converter candidates. With an output current specification of 100A, the series-parallel resonant converter (SPRC) is superior due to its simpler output stage. The thesis presents the design of a 500W SPRC for a wastewater treatment cell stack. A rudimentary cell model is derived experimentally. The closed loop analysis, controller design and simulation results are presented. The output voltage and current are estimated using sensed quantities extracted from the high voltage, low current primary side. Low voltage experimental results verify the operation of the power stage and voltage estimation circuitry in open loop pulsed operation.

Keywords: resonant converter
modeling and control
electrochemical cell model
power supply
pulsed power converter
Advisor: Dawson, Francis P.
Thorpe, Steven J.
Roles of Sec5 in the Regulation of Dense-Core Vesicle Secretion in PC12 Cells

The exocyst is thought to tether secretory vesicles to specific sites on the plasma membrane. As a member of the exocyst, Sec5 is implicated in cell survival and membrane growth in Drosophila. Little is known of the exocyst function in mammals, with previous work suggesting involvement of exocyst in GTP-dependent exocytosis. Using RNA interference, we stably down-regulated Sec5 in PC12 cells. We found that these knockdown cells exhibit decreased GTP- and Ca2+-dependent exocytosis of dense-core vesicles (DCVs), and contain less proportion of docked vesicles. Expression of Sec6/8 is also slightly reduced in Sec5 knockdown cells. Our results suggest that Sec5 is involved in both GTP- and Ca2+-dependent exocytosis, possibly through the regulation of DCV docking. We also established doxycycline-inducible knockdown system for Sec5 in PC12 cells which may be more appropriate to study development-related proteins. Efforts were also made to re-introduce Sec5 into the Sec5 knockdown cells for rescue purposes.

Keywords: dense-core vesicle
exocytosis
docking
tethering
exocyst
Sec5
Advisor: Sugita, Shuzo
The Small Ubiquitin-related Mmodifier in the Stress Response and the Use of Mass Spectrometry/SUMmOn for Identification of Ubiquitin and Ubiquitin-like Protein Conjugation Sites

Ubiquitin (Ub) and the ubiquitin-like proteins (Ubls) are polypeptides that can be covalently conjugated to a variety of “target” molecules to modulate their turnover rate, localization and/or function. The full range of Ubl functions is only beginning to be understood. The Raught lab is using mass spectrometry and high throughput screening methods, along with standard cell biology and biochemistry approaches, to better understand Ubl function. Here, I describe the role of a Ubl called small ubiquitin-related modifier (SUMO) in the budding yeast alcohol stress response. We identified a regulatory mechanism of the SUMO system, involving modulation of the localization of a SUMO protease. Secondly, using mass spectrometry (MS), I assisted in identifying several yeast and mammalian Ubl “chain” linkages. Finally, I propose an integrated MS methodology designed to complement standard database software for the confident identification of Ub/Ubl conjugation sites.

Keywords: SUMO
mass spectrometry
ubiquitin
alcohol stress
NEDD8
SUMmOn
Advisor: Raught, Brian
Hydrogel/Electrospun Fiber Composites Influence Neural Stem/Progenitor Cell Fate

Cell replacement therapy with multi-potent neural/stem progenitor cell into the injured spinal cord is limited by poor survival and host tissue integration. An injectable and biocompatible polymeric cell delivery system serves as a promising strategy to facilitate cell delivery, promote cell survival and direct cell behaviour. We developed and characterized the use of a physical hydrogel blend of hyaluronan and methylcellulose for NSPC delivery, and incorporated electrospun fibers of collagen or P(CL:DLLA) to promote cell-matrix interactions and influence cell behaviour. HAMC was shown to be both cytocompatible and allow NSPC differentiation in vitro. Inclusion of electrospun fibers in the HAMC hydrogel further influenced cell behaviour. Composite systems of P(CL:DLLA) fibers in HAMC maintained cell survival/proliferation and enhanced neuronal and oligodendrocytic differentiation similar to HAMC. The importance of the cell delivery vehicle to NSPC survival and cell fate was demonstrated in vitro and will be tested in on-going studies in vivo.

Advisor: Shoichet, Molly
Comparing the Use of Abundance and Consistent Occupancy Measures to Predict Local Species Persistence

I compared the utility of two continuous time-series data measures for applied conservation biology by investigating how well each could predict future local persistence of a diverse set of bird species. I used 37 years of data from the North American Breeding Bird Survey to calculate abundance from yearly point-counts and permanence (i.e., consistent occupancy over time) from yearly presence-absence data in the early portion of the study period, then used the later portion of data to empirically evaluate how well each measure predicted persistence two decades into the future. I found that permanence could only match the ability of abundance to accurately predict local species persistence if multiple within-year repeated observations contributed to its calculation. Neither measure was effective at predicting persistence for regionally rarer species. I suggest the yearly and within-year repeated collection of abundance estimating data for use in applied conservation biology to best ensure biodiversity persistence.

Keywords: persistence
point-count
presence-absence
abundance
permanence
Breeding Bird Survey
area selection
reserve design
Advisor: Manne, Lisa
The Effect of Treadmill Walking on the Stride Interval Dynamics of Children

The stride interval of typical human gait is correlated over thousands of strides. This statistical persistence diminishes with age, disease, and pace-constrained walking. Considering the widespread use of treadmills in rehabilitation and research, it is important to understand the effect of this speed-constrained locomotor modality on stride interval dynamics. To this end, and given that the dynamics of children have been largely unexplored, this study investigated the impact of treadmill walking, both with and without handrail use, on paediatric stride interval dynamics. An initial stationarity analysis of stride interval time series identified both non-stationary and stationary signals during all walking conditions. Subsequent scaling analysis revealed diminished stride interval persistence during unsupported treadmill walking compared to overground walking. Finally, while the correlation between stride interval dynamics and gross energy expenditure was investigated in an effort to elucidate the clinical meaning of persistence, no simple linear correlation was found.

Keywords: stride interval
gait
persistence
detrended fluctuation analysis
stationary
reverse arrangements test
energy expenditure
Advisor: Chau, Tom
A Method to Identify DNA Sequences Contained in an Arbitrary Nuclear Region

Nuclear substructures known as “nuclear bodies” associate with particular gene loci, and this may determine or reflect a mechanism of genetic control. The detection of these associations currently relies on the use of loci-specific probes, or immunoprecipitation of bulk cells with a particular protein. However, there is evidence that these associations respect the nuclear body, not necessarily any one constituent protein, and are statistically and/or functionally significant even when they occur over distances resolvable by light microscopy, or within single cells. A method is proposed that will allow for the identification of loci contained within the vicinity of an arbitrary nuclear structure in a single cell. It is demonstrated that the crucial aspects of this method are feasible; that DNA sequences originating from arbitrary subnuclear regions targeted by two-photon irradiation can be determined, and identified to a particular locus.

Keywords: general biology
genetics
molecular biology
Advisor: Bazett-Jones, David
The Role of P62 in Autophagy of Salmonella Enterica Serovar Typhimurium

Autophagy, a cellular degradative pathway, plays a key role in protecting the cytosol from bacterial colonization, but the mechanisms of bacterial recognition by this pathway are unclear. Autophagy is also known to degrade cargo tagged by ubiquitinated proteins, including aggregates of misfolded proteins, and peroxisomes. Autophagy of ubiquitinated cargo requires p62, an adaptor protein with multiple protein-protein interaction domains. Previous studies demonstrated that the intracellular bacterial pathogen S. typhimurium is targeted by autophagy during infection of host cells. Here I show that p62 is recruited to S. typhimurium targeted by autophagy, and that the recruitment of p62 is associated with ubiquitinated proteins localized to the bacteria. Expression of p62 is required for efficient autophagy of bacteria, and restriction of their intracellular replication. My study demonstrates that the surveillance of misfolded proteins and bacteria occurs via a conserved pathway and reveals a novel function of p62 in innate immunity.

Keywords: Autophagy
Salmonella
Advisor: Brumell, John
Economic, Social and Cultural Rights in New Zealand: Their Current Legal Status and the Need for Change

In this thesis I examine the status of the rights recognised in the International Covenant on Economic, Social and Cultural Rights in New Zealand‘s domestic law. I contrast that status with the constitutional guarantees that Brazil, South Africa and Finland provide for these rights, and critique the principal objections made in New Zealand and elsewhere against them. I argue that greater domestic legal protection of economic, social and cultural rights is necessary and propose that they be incorporated into the New Zealand Bill of Rights Act 1990.

Keywords: Economic, social and cultural rights, legal status in New Zealand, New Zealand Bill of Rights Act 1990, International Covenant on Economic, Social and Cultural Rights
Advisor: Macklem, Patrick
The Role of Champions in the Implementation of Patient Safety Practice Change

Objectives: The concept of clinical champions has been widely promoted, yet empirically underdeveloped in health services literature. The objectives of this study are to investigate the role of the clinical champion and how it contributes to effective patient safety change. Methods: Case study design was used to examine the role of champions in the implementation of rapid response teams in two hospitals. Central themes were derived through qualitative analysis of semi-structured interviews with key informants. Results: Analysis revealed a typology of champions: clinical, managerial, and executive. Champions engaged in five core activities: disseminating knowledge, advocating, building relationships, navigating boundaries, and facilitating consensus. Individuals became champions by informal emergence or by formal appointment combined with informal emergence. Conclusions: This study furthered understanding of patient safety champions by revealing types, activities, and modes of emergence. Findings will allow health care professionals to use an evidence-based approach to identifying and supporting champions.

Keywords: patient safety
change management
health care
champions
Advisor: Berta, Whitney B.
Acquisition of Hebrew Noun Plurals in Early Immersion and Bilingual Education

This study examined the acquisition of Hebrew noun plurals in early immersion and bilingual education by focusing on performance, as well as morpho-syntactic and semantic errors in inflecting nouns. A total of 196 students from Senior Kindergarten (n = 86) and grades 1 (n = 58) and 2 (n = 53) were administered measures of inflectional morphology in Hebrew. Results indicated that children applied high frequency, salient, simple to apply inflectional patterns involving male-female nouns, as well as the basic way of noting plurality. Two major obstacles in the pluralisation of Hebrew nouns were suffix regularity and stem transparency. Error analysis revealed three categories of responses: rule-based, analogy-based and non-strategic errors. The principal conclusion was that errors notwithstanding, young children learning Hebrew as a foreign language are moving toward an understanding of plural formation. The development of morpho-syntactic structures gradually develops over time and with exposure to Hebrew instruction.

Keywords: morphology
Hebrew
Error Analysis
Second Language Acquisition
Advisor: Geva, Esther
Real People, Real Needs: Deaf Education in Dadaab Refugee Camp in Kenya

This thesis is a study into the lived educational experiences of selected individuals; administrators, teachers, Deaf students and community members, who are a large part of the Deaf education program in Dadaab Refugee Camp in Kenya. Currently, little is known about the experiences of Deaf refugees in a refugee camp. The objective of this thesis is to understand of the role(s) Deaf Units play in terms of opportunities and obstacles for those involved in the Deaf education community in the Dadaab refguee camp. This study focuses on qualitative data, collected through videotaped interviews with 65 participants to bring forth their experiences and perspectives. This study also links the school improvement change theoretical framework to help us better understand the opportunities and obstacles encountered by the involved stakeholders. Key factors affecting the opportunities and obstacles of the Deaf education program in a refugee camp are presented.

Keywords: 0529
0514
Advisor: Anderson, Stephen
Nana Yaa Asantewaa, The Queen Mother of Ejisu: The Unsung Heroine of Feminism in Ghana

This thesis examines the life story of Nana Yaa Asantewaa and its pedagogical implications for schooling and education in Ghana and Canada. Leadership role among women has been a topic in many debates for a long period. For many uninformed writers about the feminist struggles in Africa, Indigenous African women are docile bodies with little or no agencies and resistance power. However, the life history of Nana Yaa Asantewaa questions the legitimacy and accuracy of this misrepresentation of Indigenous African women. In 1900, Yaa Asantewaa led the Ashanti community in a war against the British imperial powers in Ghana. The role Yaa Asantewaa played in the war has made her the legend in history of Ghana and the feminist movement in Ghana. This dissertation examines the traits of Yaa Asantewaa and the pedagogic challenges of teaching Yaa Asantewaa in the public schools in Ghana and Canada.

Keywords: Indigenous Leadership
Yaa Asantewaa
The Unsung Heroine
Queen mother of Ejisu
Feminism in Ghana
Yaa Asantewaa War
Yaa Asantewaa, role in Ashanti/British War
The Golden Stool
The Ashanti/British War
The Akans (Ashanti)
Advisor: Dei, George Jerry Sefa