identifier: Wilton, Peter <https://research.library.mun.ca/view/creator_az/Wilton=3APeter=3A=3A.html>   (2014) An examination of two mechanisms of public engagement in central Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: This project is an examination of two types of engagement mechanisms, online and in-person focus groups, used in a large multi-sector public engagement initiative held in Central Newfoundland, between February and July 2013. Each mechanism is evaluated according to a seven point evaluative framework which was developed by the researcher and includes data collected from surveys administered to participants and key informant interviews with the organizers of the initiative. Components of the evaluative framework included resource accessibility, task definition, independence, likelihood to participate again, representativeness, fairness and expectations of the organizers. Overall, focus group participants felt much more positive about the criteria of task definition, independence, fairness and were much more likely to feel strongly about participating in a similar initiative again. While both engagement mechanisms tended to be unrepresentative of the population of Central Newfoundland, due to the low level of participation for the online component, it is difficult to conclude which mechanism better represented the demographic make-up of the population. Initially, organizers felt very positive and optimistic about the online component. After the initiative, however, they discussed ways of improving the online experience and reiterated their support for using two mechanisms of engagement for future initiatives.


identifier: Qian, Yiming <https://research.library.mun.ca/view/creator_az/Qian=3AYiming=3A=3A.html>   (2014) Self-tuning one-class support vector machines for data classification.  Masters thesis, Memorial University of Newfoundland.

type: Thesis NonPeerReviewed

abstract:
Support Vector Machine (SVM) based classifiers are most popular models for data
classification in machine learning. To obtain high classification accuracy, parameter
tuning methods such as cross-validation are often applied, which is however timeconsuming.
To address this problem, a simple, efficient and parameter-free algorithm
is presented in this thesis. The algorithm is especially useful when dealing with
datasets in the presence of label noise. Grown out of one-class SVM, the presented
algorithm enjoys several distinct features: First, its decision boundary is learned based
on both positive and negative examples, whereas the original one-class SVM training
is only based on positive examples; Second, the internal parameters are self-tuned,
which makes the algorithm handy to use even for first-time users. Compared with the
benchmark method LIBSVM, the presented algorithm achieves comparable accuracy,
while consuming only a fraction of the processing time. Applications in computer
vision are presented to demonstrate the effectiveness of the algorithm.


identifier: Sano, Yujiro <https://research.library.mun.ca/view/creator_az/Sano=3AYujiro=3A=3A.html>   (2014) Does regionalisation of immigration work in Canada? Comparative analyses on economic performance of recent immigrants in Atlantic Canada and traditional destinations.  Masters thesis, Memorial University of Newfoundland.

abstract: Despite growing interest in new immigration gateway research, comparative analyses of the economic performance between new and traditional destinations among recent immigrants are limited. As a case study from Atlantic Canada, this research addresses two main questions. First, are earnings disadvantages of recent immigrants relative to their native-born counterparts smaller in Atlantic Canada than Montreal, Toronto, and Vancouver (i.e., MTV)? Second, do recent immigrants in Atlantic Canada earn more than recent immigrants in MTV? My analysis of the 2006 Canadian Census data finds recent immigrants' low earnings are less severe in Atlantic Canada than in MTV. Moreover, earnings disadvantages associated with being racial minorities, speaking non-official languages at work or home, and possessing foreign credentials are smaller in Atlantic Canada than in MTV. Recent immigrants who speak non-official languages at work in Atlantic Canada earn more than those in MTV. Finally, those who have obtained highest education from Northern Europe earn less in Atlantic Canada than in MTV. Finally, I discuss implications of these findings for policy recommendations and future studies.


identifier: Wen, Yubing <https://research.library.mun.ca/view/creator_az/Wen=3AYubing=3A=3A.html>   (2014) Random nonlinear dynamics of a spur gear pair by path integration.  Masters thesis, Memorial University of Newfoundland.

abstract:
The research investigates the random nonlinear vibration of a spur gear pair subjected
to both deterministic and random loads by path integration method. Different models
and approaches to apply the path integration method are presented in Chapters 2–
4. Backlash nonlinearity and time-varying mesh stiffness in gear systems are both
considered in Chapters 2 and 3. In Chapter 2, the time-varying mesh stiffness is
modeled as a constant plus a cosinusoidal component, and the discontinuous backlash
nonlinearity is approximated with a cubic polynomial through curve fitting. Then
Gaussian closure procedure is employed to obtain the mean and variance of transition
probability density function (PDF). In Chapter 3, the time-varying mesh stiffness is
approximated with a square wave function. The variance of the responses is calculated
and expressed as closed forms for two different cases in gear systems. In Chapter
4, the gear rattling model which only considers backlash is presented. A degenerate
Gaussian distribution is employed as transition PDF. The path integration results are
compared with deterministic results (Chapters 2 and 3) and Monte Carlo simulation
results (Chapters 3 and 4). Good agreement is found between them, which could verify
the accuracy of path integration method in the study of random gear dynamics.


identifier: Kolypetri, Panagiota <https://research.library.mun.ca/view/creator_az/Kolypetri=3APanagiota=3A=3A.html>   (2014) Studies on the immunoregulation of autoimmune thyroiditis.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Autoimmune thyroiditis is a chronic disease characterized by mononuclear cell
infiltration in the thyroid gland and production of anti-thyroglobulin (Tg) antibodies. In
this thesis, we have used the murine models of experimental autoimmune thyroiditis
(EAT) and iodide-accelerated spontaneous autoimmune thyroiditis (ISAT) to investigate
the immunoregulation of the disease.
In the EAT model, we have examined whether putative H2Aᴷ-binding Tg epitopes,
located adjacent to cathepsin cleavage sites within mouse Tg would have
immunopathogenic properties. The peptides, p2369 and p2439, elicited significant
proliferative T cell responses and production of IL-2 and IFN-γ in recall assays using
lymph node cells from peptide-primed mice. Both peptides were pathogenic in CBA/J
mice after direct challenge with the peptide in CFA and by adoptive transfer of peptideprimed
lymph node cells into naïve recipient hosts.
In the ISAT model, we have examined whether NOD.H2ᴴ⁴ thyrocytes are highly prone to
iodide-mediated apoptosis since such an event could theoretically trigger ISAT in this
strain. Our data showed that NOD.H2ᴴ⁴ thyrocytes cultured with low NaI concentrations
had significantly higher apoptotic rates compared to CBA/J thyrocytes. Increased
apoptosis was associated with an impaired control of oxidative stress mechanisms since
the expression of only two genes involved in ROS metabolism and/or anti-oxidant function were upregulated in iodide-treated NOD.H2ᴴ⁴ thyrocytes vs. 22 genes in iodidetreated
CBA/J thyrocytes. Next, we examined the immunopathogenicity of the Tg
epitope, a.a. 2549-2560 (T4p2553) in NOD.H2ᴴ⁴ mice. The epitope was
immunopathogenic in this strain after direct challenge with peptide in CFA. In ISAT,
peptide-specific proliferative responses were recorded using only cervical lymph node
cells (CLNC) from iodide-fed mice before the onset of the disease. Also, selective
enrichment of CD4⁺ IFN-γ⁺ T4p2553-specific cells was observed among CLNC and
intrathyroidal lymphocytes. T4p2553 was equally detectable on dendritic cells from
CLNC regardless of iodide intake whereas spontaneous T4p2553-specific IgG responses
were not detectable. Our data identified for the first time a Tg T-cell epitope as a
spontaneous target in ISAT.
Lastly, we have examined whether a high salt diet can exacerbate autoimmune thyroiditis
because previous studies by other groups had suggested this diet as a predisposing factor
for autoimmune diseases in general. Our data showed that high salt intake failed to
significantly affect the incidence and severity of SAT in NOD.H2ᴴ⁴ mice or EAT in Tgprimed
C57BL/6J and T4p2553-primed CBA/J mice relative to mice on a normal diet.
No difference was detected at the Tg-specific IgG levels between the two groups. These
data demonstrate that a high salt diet is not a risk factor for all autoimmune diseases.


identifier: Lin, Dan <https://research.library.mun.ca/view/creator_az/Lin=3ADan=3A=3A.html>   (2015) Methods for analyzing power system small signal stability.  Masters thesis, Memorial University of Newfoundland.

abstract:
Small disturbance such as load changes will affect stability of power systems. Small signal stability problem refers to the stability problems caused by small disturbances. Power oscillation appears in the system because of the effect of small disturbances. Oscillation's property is the key to analyze the stability of power system. The undamped power oscillation may cause the blackout, such as the power outage of North American Western Interconnected (WSCC) System happened in 1996.
In order to learn the oscillation's mode, two methods are applied to analyze the oscillation caused by small disturbances. The first method is referred to as model-based analysis for small signal stability problem. It uses mathematical model to indicate whether the system is stable based on the eigenvalue calculation for the mathematical model. The other method is the measurement-based analysis for power system. This method is more popular for today's power system analysis. It uses real-time synchrophasor measurement collected from Phasor Measurement Units (PMUs) that are installed at various buses to estimate the mode of oscillations based on prony method. This method requires the system to be visible using PMUs. In addition, the mode of oscillation for every bus can be detected with the time stamp.
This thesis studies these two methods to analyze different power systems. The advantages of using measurement-based analysis are clearly shown in this research. As the power system is highly dynamic, model-based analysis cannot provide accurate real-time information. However, the challenge for applying measurement-based analysis is to find the optimum locations for installing PMUs so that non-observable area does not exist in the whole system. Case studies using four different power system models are presented throughout the thesis.


identifier: Regular, Paul M. <https://research.library.mun.ca/view/creator_az/Regular=3APaul_M=2E=3A=3A.html>   (2014) Foraging strategies of a pursuit-diving seabird in a dynamic marine environment.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Flexible foraging tactics are critical to survival for predators foraging in dynamic environments. This is especially true for breeding seabirds as they have to fuel their own energy needs and those of their offspring from a fixed breeding site. To succeed parents must employ foraging strategies that maximize overlap with prey through a range of environmental conditions.
Off Newfoundland, breeding common murres Uria aalge specialize on capelin Mallotus villosus. The spatial and temporal distribution of capelin is, therefore, expected to influence the foraging decisions of murres. Though capelin are predictable in many ways, several physical challenges (travel time, light limitations, etc.) limit the murres’ foraging activities. This research focuses on how common murres breeding in Newfoundland deal with their foraging ocean-scape. Integrated analyses of tracking data, colony-based observations, vessel surveys of prey, and physical environmental measurements were used to assess this question.
To deal with environmental change, murres exhibited remarkable behavioural flexibility. Though diel vertical migrations of capelin challenged their diving and visual abilities, murres successfully captured capelin throughout diurnal, crepuscular (twilight), and nocturnal periods. They used moonlight to capture capelin at night and also appeared to rely on non-visual cues to capture capelin under a starlit sky – when virtually no light is available in the water column. Over horizontal scales, murres appear to rely on memory to relocate successful foraging patches and area-restricted search to refine their foraging efforts. Because capelin tend to occur in predictable patches that are ephemeral at fine scales, this is likely the most efficient strategy. In combination with flexible time budgets, these strategies likely help murres buffer chick-feed rates across a range of prey densities. However, during mismatch between chick-rearing and peak capelin availability, parental murres were unable to fully compensate for limited access to prey and breeding success was consequently reduced. Though murres exhibit remarkable behavioural plasticity, there are limits to their plasticity. Revealing the limits improves our mechanistic understanding of the links between environmental variability and population dynamics.


identifier: Bastin, Tony <https://research.library.mun.ca/view/creator_az/Bastin=3ATony=3A=3A.html>   (2014) Mathematical modeling of propeller wake wash for pack-ice management.  Masters thesis, Memorial University of Newfoundland.

abstract: Propeller wake wash has been used effectively for ice management operations for years. The main uses of propeller wake wash include clearing pack ice and broken ice from offshore installations and shipping channels. A numerical model of a propeller wake has been developed to simulate the effect of the wake, or jet, on ice pieces floating on the water surface. The propeller jet was modeled using empirical equations derived from previous experiments. Model predictions are compared to experimental results of pack ice subjected to propeller wake wash. The analysis shows that this model can be used to simulate the clearing of pack ice. It has potential to be applied to model ice management operations.


identifier: Dobrota, Therese <https://research.library.mun.ca/view/creator_az/Dobrota=3ATherese=3A=3A.html>   (2014) Integrated soil analysis at an Inuit tent camp: Huntingdon Island 5 (FkBg-3), Sandwich Bay, South Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract:
The history of Labrador Inuit archaeology reflects a disproportionate focus on the sod
house, characteristic of the winter settlement. However, the sod house represents only a part of
the traditional Inuit yearly foraging round. Throughout the warmer seasons, including spring,
summer, and early autumn, Inuit lived in skin tents. Although they are representative of a broader
seasonal range of subsistence practices, tent camps have seldom been studied. This is due to the
poor material assemblages and limited structural remains that characterize these sites, which
makes it difficult to approach them through conventional excavation methods. This thesis
engages with the potential of a systematic study of Inuit tent camp sites through the development
of a more suitable method of analysis. For this purpose, bulk soil samples and undisturbed cores
were collected from soils associated with Tent Ring 1 and Tent Ring 4 from Huntingdon Island 5
(FkBg-3), in Sandwich Bay, southern Labrador, and a soil and vegetation survey were carried out
at the site. Ethnographic data was used to interpret the structures, guide sampling procedures and
formulate working hypotheses, which were tested through the joint application of thin section
micromorphology, soil chemistry and paleoethnobotanical analysis under the heading of
integrated soil analysis. This approach is designed to address specific issues connected to the
southern Labrador landscape, such as the shallowness of acidic tundra soils and the narrow
buffer zone between the active layer of plant growth and the archaeological layer, and to answer
questions about the taskscape associated with the tent rings, as well as their environmental and
taphonomic context. The analysis has provided information on the internal structure of the
dwellings and designated activity areas, reoccupation events, the length and season of
occupation, as well as a relative sequence of use, while simultaneously providing a perspective on the environmental signature of these dwellings on the south Labrador tundrascape and the
taphonomic processes that impact them.


identifier: Tukhareli, Tamara <https://research.library.mun.ca/view/creator_az/Tukhareli=3ATamara=3A=3A.html>   (2015) Analyzing the sustainability of electronic waste management in Toronto, Ontario.  Masters thesis, Memorial University of Newfoundland.

abstract:
Sustainable waste management plays a key role in achieving sustainable urban
development worldwide. Currently, the rates of waste generation are on the increase with
electronic waste comprising a significant portion of the total. This growth in the
generation of electronic waste has led to the creation of sustainable management
programs in a number of cities, including Toronto in Canada. An examination of the
existing electronic waste management system in Toronto, Ontario has provided many
insights into the structure of the relationships and the flow of the electronic waste within
the area. This thesis analyzes the sustainability of the social networks and material flow
networks that have developed within the Toronto electronic waste market. The data,
collected from the field observations in the summer, points to a relatively uneven
distribution of partnerships between the large-scale recycling corporations, government
organizations, non-profit refurbishers and the informal recyclers. The examination also
reveals a prioritization towards large-scale mechanical recycling over refurbishing and reuse
of the electronics. The effect of such distribution of material and partnerships on the
overall sustainability of the management system is discussed.


identifier: Colbourne, Peggy Amanda <https://research.library.mun.ca/view/creator_az/Colbourne=3APeggy_Amanda=3A=3A.html>   (2014) Baccalaureate nursing students' lived experience of high-fidelity pediatric simulation: a hermeneutic phenomenological study.  Masters thesis, Memorial University of Newfoundland.

abstract: Changes in nursing educational programs have led to the incorporation of high-fidelity simulation (HFS) into clinical teaching, yet little is known about students‟ experiences with this teaching-learning modality. Therefore, this hermeneutic phenomenological study was conducted to examine the lived experience of HFS for undergraduate nursing students in the context of pediatric nursing care. In-depth interviews were carried out with 12 students and were analyzed for themes using the approach of van Manen (1998). The essence of the experience is that it was eye-opening for the students. It was eye-opening in two ways. It was a surprisingly realistic nursing experience as reflected in the following themes: perceiving the manikin as a real patient, saving my patient‟s life, feeling like a real nurse, and feeling relief after mounting stress. It was a surprisingly valuable learning experience as reflected in the following themes: increased awareness of the art and science of nursing, increased recognition of the importance of teamwork, feeling more prepared for clinical practice, and wanting more simulation experiences. The findings from this study can be used to inform nursing education.


identifier: Liu, Xu <https://research.library.mun.ca/view/creator_az/Liu=3AXu=3A=3A.html>   (2014) Delay-tolerant networks with network coding: how well can we simulate real devices?  Masters thesis, Memorial University of Newfoundland.

abstract:
Delay-tolerant networking effectively extends the network connectivity in the time
domain, and endows communications devices with enhanced data transfer
capabilities. Network coding on the other hand enables us to approach the
information capacity of networks by allowing intermediate nodes to process data en
route. Both of these were major principal breakthroughs in mobile and wireless
communications in the past decade or so. In the first half of this thesis, we consider
the problem of disseminating a large number of messages in such networks. With
the sparse and intermittently connected topology and with the unreliable and
low-rate radios, the strategy of which messages to transfer first and in what order is
a determinant of performance here. We compare a few such message prioritization
methods using computer simulation and observe their performance in terms how
widely and quickly information can be distributed across the network. Next, we are
interested in how network coding stacks against conventional epidemic routing
variants. We conducted tests with both real smart mobile devices and computer
simulation and found conditions where their results match. This would give us
confidence of using computer simulation to study larger delay-tolerant networks
with and without network coding at a much manageable cost.


identifier: Jing, Liang <https://research.library.mun.ca/view/creator_az/Jing=3ALiang=3A=3A.html>   (2014) An integrated simulation-based process control and operation planning system for marine oily wastewater management.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: The chronic discharge of oily wastewater, mainly including bilge water, offshore produced water and ballast water, has been referred to as a major contributor to marine oil pollution. Although gravity-based treatment techniques have been widely used to separate oil from wastewater, many dissolved toxic organics, particularly Polycyclic Aromatic Hydrocarbons (PAHs), are not likely to be effectively removed and may cause severe environmental problems. Further treatment has therefore become necessary for the shipping and offshore oil and gas industries, particularly in the harsh environments (e.g., the Arctic Ocean) where ecosystems are extremely vulnerable. Among many chemical and biological treatment techniques, ultraviolet (UV) irradiation and advanced oxidation techniques have been recently regarded as promising solutions to the removal of PAHs. Such advanced treatment systems, as compared to the traditional ones, are usually lack of in-depth understanding of reaction mechanisms and kinetics, process control requirements, and long-term planning strategies. More particularly, the integration of process control and operation planning has been proven in the literature to greatly reduce process cost and improve system performance. However, such integration is usually complicated by many factors such as the multi-scale nature of decisions, the lack of knowledge of process dynamics and control, and uncertainty. These deficiencies can drastically hinder the widespread application of these advanced treatment systems in the shipping and offshore industries. In response to these knowledge and technique gaps, this research proposes an integrated process control and operation planning system to aid marine oily wastewater management based on experimental study, process modeling, process control, operation planning and their coupling.


identifier: Pivi, Ilaria <https://research.library.mun.ca/view/creator_az/Pivi=3AIlaria=3A=3A.html>   (2014) Partners of international students at Memorial University of Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: This study investigates the lived experiences of the partners of international students of Memorial University of Newfoundland (MUN) in relation to gender and race to address three research goals: (1) to explore partners’ lived experiences in St. John’s; (2) to examine the structural constraints that hinder partners’ full participation within the community where they live; and (3) to offer recommendations to the International Student Advising Office (ISA) of MUN for service implementations. The findings of this study suggests that the experiences of the international students’ partners are gendered and racialized with respect to childrearing, parenting responsibilities and access to local services, such as English as a Second Language classes and public transportation. Furthermore, the findings support the literature that notes structural barriers influence partners’ ability to locate and access paid employment in their area of expertise and engage with the community in general.


identifier: Hamilton, Ian R. <https://research.library.mun.ca/view/creator_az/Hamilton=3AIan_R=2E=3A=3A.html>   (2014) What makes a house a home: Examining the relationship between growth and predation risk in a coastal elasmobranch, the lemon shark (Negaprion brevirostris).  Masters thesis, Memorial University of Newfoundland.

abstract: Many shark species are known to use nursery grounds, though few use coastal habitats in the same manner as juvenile lemon sharks. Lemon sharks pup in shallow, coastal areas and although the reasons for this behaviour are unknown, the two most likely explanations are access to food and avoidance of predators. This thesis aimed to examine these ideas by testing the hypotheses that a) sites with high resource availability will yield high juvenile lemon shark abundance and b) an increase in predation risk will result in decreased juvenile lemon shark abundance and increased individual growth rates. Seine nets were set to capture juvenile lemon sharks and their fish prey. Drum lines were used to measure predator abundance outside of each of the nine study inlets, while ARCGIS mapping software was used to assess site-specific refuge availability across the entire tidal cycle. Juvenile lemon shark abundances correlated strongly with mojarra (Gerres spp.), their preferred food item. Lemon sharks also showed a weak, but non-significant positive relationship with refuge availability, but not with predator abundance. Individuals in areas with high predator presence however, showed increased growth rates. Our data suggest that juvenile lemon shark populations exhibit frequency-dependent habitat selection with respect to prey availability. Moreover, the results indicate that of the variables studied, food availability primarily determined habitat quality in nursery grounds, with a less important role for predation pressure. If lemon shark populations are constrained by juvenile recruitment, appropriate management of their coastal nursery areas offer a powerful conservation tool.


identifier: Rae, Lauren F. <https://research.library.mun.ca/view/creator_az/Rae=3ALauren_F=2E=3A=3A.html>   (2014) Assessing the impacts of moose-induced habitat change on a forest bird community.  Masters thesis, Memorial University of Newfoundland.

abstract:
Forest songbirds are sensitive to habitat disturbances that result in changes to
forest structure and composition. In Newfoundland, Canada, browsing by hyperabundant,
non-native moose (Alces alces) has caused failed regeneration across extensive
areas of forest following disturbance. I examined the impact of these habitat changes at
multiple spatial scales on forest bird occurrence and species richness within Gros Morne
National Park based on point counts that incorporated both silent intervals and intervals
during which black-capped chickadee (Poecile atricapillus) mobbing calls were
broadcast. Early successional bird species we more likely to occur with increased failed
regeneration on the landscape. Some forest habitat generalists were less likely to occur
with increased failed regeneration cover at the local scale. Comparing detection
probabilities across silent and playback intervals for 17 species, I found that playbacks
increased detection rates for seven species, and either had no effect or decreased
detection rates for the remaining ten species.


identifier: Zhang, Liuhua <https://research.library.mun.ca/view/creator_az/Zhang=3ALiuhua=3A=3A.html>   (2014) Automatic mammogram analysis using wavelet-fourier transforms and entropy-based feature selection.  Masters thesis, Memorial University of Newfoundland.

abstract:
Breast cancer is the second leading cause of cancer-related death after lung cancer in women. Early detection of breast cancer in X-ray mammography is believed to have effectively reduced the mortality rate since 1989. However, a relatively high false positive rate and a low specificity in mammography technology still exist. A computer-aided automatic mammogram analysis system in this research is proposed to improve the detection performances.
In designing this analysis system, the discrete wavelet transforms (Daubechies 2, Daubechies 4, and Biorthogonal 6.8) and the Fourier cosine transform were first used to parse the mammogram images and extract statistical features. Then, an entropy-based feature selection method was implemented to reduce the number of features. Finally, different pattern recognition methods (including the Back-propagation Network, the Linear Discriminate Analysis, and the Naïve Bayes Classifier) and a voting classification scheme were employed. The performance of each classification strategy was evaluated for sensitivity, specificity, and accuracy and for general performance using the Receiver Operating Curve. The experiment demonstrated that the proposed automatic mammogram analysis system could effectively improve the classification performances, especially using the voting classification scheme based on the selected optimal features.


identifier: Ansari, Seyedmasoud <https://research.library.mun.ca/view/creator_az/Ansari=3ASeyedmasoud=3A=3A.html>   (2014) Three dimensional finite-element numerical modeling of geophysical electromagnetic problems using tetrahedral unstructured grids.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Finite-element solutions to the three-dimensional geophysical electromagnetic forward
modeling problem in the frequency domain are presented. The method is firstly examined
for the solution to the E-field Helmholtz equation. Edge-element basis functions
are used for the electric field. An alternative method is also used which is based
on decomposing the electric field into vector and scalar potentials in the Helmholtz
equation and in the equation of conservation of charge. Edge element and nodal
element basis functions are used respectively for the vector and scalar potentials.
This decomposition is performed with the intention of satisfying the continuity of the
tangential component of the electric field and the normal component of the current
density across the inter-element boundaries, therefore finding an efficient solution to
the problem. The computational domain is subdivided into unstructured tetrahedral
elements. The system of equations is discretized using the Galerkin variant of the
weighted residuals method, with the approximated vector and scalar potentials as the
unknowns of a sparse linear system. Both iterative and direct solvers are used for the
solutions to the E-field and decomposed systems. A generalized minimum residual
solver with an incomplete LU preconditioner is used to iteratively solve the system.
The direct solver, MUMPS, is used to provide the direct solution to the system of
equations. The forward modeling methods are validated using a number of examples.
The fields generated by small dipoles on the surface of a homogeneous half-space are compared against their corresponding analytic solutions. The next example provides
a comparison with the results from an integral equation method for a long grounded
wire source on a model with a conductive block buried in a less conductive half-space.
The decomposed method is also verified for a large conductivity contrast model where
a magnetic dipole transmitter-receiver pair moves over a graphite cube immersed in
brine. Solutions from the numerical approach are in good agreement with the data
from physical scale modeling of this scenario. Another example verifies the solution
for a resistive disk model buried in marine conductive sediments. For all examples,
convergence of the solution that used potentials was significantly quicker than that
using the electric field. The inductive and galvanic components of the electromagnetic
response are also investigated for the above examples. Furthermore a detailed investigation
of these effects are presented for models with varying conductivity contrasts.
The characteristics of the solutions in terms of implicitly and explicitly enforcing the
Coulomb gauge condition are investigated for the decomposed system. Numerical
computations show that for the above-mentioned grounded wire example the electromagnetic
response is significantly affected by the contribution from the galvanic
part. By contrast for the example where a magnetic dipole excites a graphite cube
immersed in brine solutions, the inductive scenario dominantly contributes to the
model’s electromagnetic response.


identifier: Card, Breanne Elizabeth Cornell <https://research.library.mun.ca/view/creator_az/Card=3ABreanne_Elizabeth_Cornell=3A=3A.html>   (2014) Forest Kindergarten: A qualitative case study comparing the emergent and play-based curriculum at Cedarsong Nature School to the Newfoundland and Labrador Kindergarten Curriculum.  Masters thesis, Memorial University of Newfoundland.

abstract:
Kindergarten is a German word, meaning children’s garden. Today, professionals and
parents around the world are speaking up and supporting the research that suggests young
children benefit from time spent outside in natural environments and green, wild spaces.
Some names for these programs are: Forest Kindergarten, Nature Kindergarten, or Forest
Schools.
In this qualitative study I provide a descriptive narrative single case study
composed of topic-centered narratives revealing significant themes and rich descriptions
of a Forest school. The research questioned whether the expectations of the
Newfoundland and Labrador Kindergarten Curriculum could be achieved using a Forest
Kindergarten model. The data for this case study was collected through interviews,
observations, field notes, artifacts, photographs, video recordings, and audio-visuals to
examine the concept of Forest Kindergarten as implemented by Cedarsong Nature
School on Vashon Island, WA.
Upon investigation, the researcher concludes that Forest Kindergarten programs
do meet and offer children learning opportunities to reach beyond the specific curriculum
outcomes specified for the kindergarten curriculum in Newfoundland and Labrador. The
findings suggest the advantages of a Forest Kindergarten program include advanced
communication, social, and critical thinking and problem-solving skills, a stronger sense
of self, place, and community, as well as the importance of creative play-based learning
and sensory-based play. It is recommended that the Forest Kindergarten model be
considered for Newfoundland and Labrador schooling in particular Aboriginal
communities and schools.


identifier: Hand, Aimee M. <https://research.library.mun.ca/view/creator_az/Hand=3AAimee_M=2E=3A=3A.html>   (2014) Factors regulating nuclear localization of MIER1 alpha isoforms.  Masters thesis, Memorial University of Newfoundland.

abstract:
Mesoderm induction early response 1 (MIER1) gene is located on human chromosome 1p31.2 and encodes a nuclear protein. MIER1 encodes four distinct proteins with a common internal sequence and variable N- and C-termini. MIER1α, the α C-terminus with 23 amino acids and an LXXLL motif for interaction with nuclear hormone receptors, interacts with the estrogen receptor alpha (ERα) in vivo and decreases growth of T47D cells. This study investigated the effect of MIER1α on proliferation and/or survival of human breast adenocarcinoma cells, MCF7, and T47D cells, and the results demonstrated that MIER1α had no effect on cell number.
Previous work has revealed that the subcellular localization of MIER1α changes, and loss of nuclear MIER1α might contribute to the advancement of breast cancer. A third isoform arises at the N-terminus, MIER1-3Aα, and contains a leucine-rich nuclear export signal. Inclusion of this exon in MIER1α, to produce MIER1-3Aα, changes its subcellular localization from nuclear to cytoplasmic. It has been shown that the percentage of cells appearing with nuclear MIER1α is different in MCF7 and T47D cells at 78.9 % and 9.2 %, respectively. These two cell lines are cultured under different serum conditions and therefore, the effect of factors in serum on nuclear localization was investigated. Serum was shown to have an appeared effect on nuclear localization of MIER1 isoforms in MCF7 cells, and MIER1α in T47D cells. To investigate the effect of an extracellular growth factor on localization, insulin was added to the cell culture medium. Insulin was shown to have an appeared effect on localization of MIER1α in MCF7 cells. Our results demonstrate that factors in serum may be important to control the nuclear localization of proteins.


identifier: Assiri, Yousif <https://research.library.mun.ca/view/creator_az/Assiri=3AYousif=3A=3A.html>   (2014) Complexation properties of upper- and lower-rim functionalized calix[4]arenes.  Masters thesis, Memorial University of Newfoundland.

abstract:
The work described in this thesis is concerned mainly with a study of the complexation properties of some new molecular receptors, which were synthesized by Dr. Shofiur Rahman in the research laboratory of Dr. Paris Georghiou at Memorial University. Their complexation properties with some Group 1, Group 2 and transition metal cation guests were studied.
Chapter 1 provides an overview of calixarenes and supramolecular chemistry and the methods employed herein.
In Chapter 2, as part of the on-going studies on the development of a microcantilever-based real-time device employing modified calixarene-derived sensing layers in a collaborative project with the research group of Dr. Luc Beaulieu in the Department of Physics and Physical Ocenaography at MUN, a study was undertaken to determine the solution-phase complexation properties of 5 and its ethyl analogue 6, using ¹H-NMR spectroscopic titrations.
The work described in Chapter 3 concerns the study of the supramolecular complexation behaviour of tetra-n-butylammonium halides (TBAX: X = Cl¯, Br¯) in different commonly-employed deuterated solvents such as CD3OD, (CD₃)₂CO, CD₂Cl₂, CD₃CN and DMSO-d₆, using ¹H-NMR spectroscopy.
Chapter 4, describes of new macrocyclic receptors namely, triazolyl-bridged naphthalene-calix[4]arenes, which were succssfully synthesised by Dr. Shofiur Rahman in the research laboratory of Dr. Paris Georghiou at MUN. In the study reported herein, their complexation properties with various metal ions were investigated using both fluorescence spectroscopy and ¹H-NMR spectroscopy.


identifier: Išvanková, Zuzana <https://research.library.mun.ca/view/creator_az/I==0161vankov=E1=3AZuzana=3A=3A.html>   (2014) Simple models for predicting electron correlation.  Masters thesis, Memorial University of Newfoundland.

abstract:
After almost a century since the postulation of quantum mechanics, the only chemical systems that can be treated exactly are those with one electron. For all many-electron problems we rely on approximate solutions to the electronic Schrödinger equation. The single largest error in the calculations is due to the lack of an accurate representation of what happens when two electrons come close together. How the motion of one electron is affected by that of the other electron is referred to as electron correlation. Not only is electron correlation a fundamental problem in quantum chemistry, it is also crucial in determining the important chemical effects.
The correlated motion of electrons with opposite spins, completely neglected in single-determinantal Hartree-Fock theory, remains as one of the central unsolved challenges in quantum chemistry. Simple models that can account for the missing correlation energy have been investigated for the isoelectronic atomic series of two to eighteen electrons in order to gain further insight into the form of a correlation operator. The strength of the electron correlation likely depends on both their separation in position space and their separation in momentum space; hence, it is expected that the correlation energy is related to the average inter-electron distance and to their kinetic energy. It has been previously shown that the average electron-electron distance is inversely proportional to the Coulomb energy; thus, the correlation energy was modelled as a function of Coulomb repulsion and kinetic energies. Additionally, application of the atomic correlation models to the modeling of the correlation energy for simple molecular systems have been explored.


identifier: Allehyane, Bashaeer <https://research.library.mun.ca/view/creator_az/Allehyane=3ABashaeer=3A=3A.html>   (2014) Tandem mass spectrometric analysis of bacterial lipid A and synthetic glycosyl donors containing the 2-amino-2-deoxy-D-glucosaminyl moiety.  Masters thesis, Memorial University of Newfoundland.

abstract:
This study presents an interpretation of the mass spectrometry gas-phase fragmentation
patterns of the extracted lipid A obtained from the native LPS extracts isolated from
Aeromonas Liquefaciencs. This LPS SJ-19 is known to infect various fish species
(Atlantic salmon and cod) which are cultivated in aquaculture ventures. The exact
molecular structure of the lipid A and the core oligosaccharide region of this Rough
bacterium have not yet been precisely established. This thesis presents the mass
spectrometric fingerprint identification and structural elucidation of the lipid A from A.
Liquefaciencs, which was accomplished via the use of electrospray ionization tandem
mass spectrometry (ESI-MS/MS using FTICR, QIT, QHQ-MS/MS) and matrix assisted
laser desorption ionization tandem mass spectrometry (MALDI-MS/MS).
In this work, tandem-in-time and tandem-in-space mass spectrometry was chosen
for the structural elucidation of the lipid A isolated from A. Liquefaciencs SJ-19. The
concomitant uses of high-energy and low-energy collision induced dissociation (CIDMS/
MS) analysis were also used to elucidate the MS/MS fingerprints of this complex
biomolecule and can be effectively used for any quantitative or qualitative studies.
In addition, a novel MS/MS study of a series of 2-acylated-2-deoxy-Dgluosamine
glycosyl donors is also presented using ESI-MS/MS tandem-in-space and
tandem-in-time mass spectrometry.


identifier: Hayes, Ian <https://research.library.mun.ca/view/creator_az/Hayes=3AIan=3A=3A.html>   (2015) "It's a balancing act. That's the secret to making this music fit in today": negotiating professional and vernacular boundaries in the Cape Breton fiddling tradition.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Originating from the music of early Gaelic immigrants, Cape Breton fiddling has
been a thriving musical tradition for more than two hundred years. It eventually rose to
prominence in the 1990s, receiving international recognition in the music industry. As the
“Celtic boom” faded and major record labels lost interest in the tradition commercially,
Cape Breton traditional musicians continued to maintain a presence in the music industry,
though their careers now enjoy more modest success. All the while, Cape Breton fiddling
has remained a healthy, vibrant tradition on the local level, where even the most
commercially successful musicians have remained closely tied to their roots.
This thesis examines how Cape Breton traditional musicians negotiate and express
their musical identities in professional and vernacular contexts. As both professional
musicians and tradition bearers, they are fixtures in popular culture, as well as the local
music scene, placing them at an intersection between global and local culture. While
seemingly fairly homogenous, Cape Breton fiddling is rich and varied tradition, and
musicians relate to it in myriad ways. This plurality and intersubjectivity of what is
considered to be “legitimate” culture is evident as the boundaries of tradition are drawn
and change according to context. Musicians engage with, and critically evaluate cultural
discourses surrounding the tradition which are influenced by power, cultural capital,
social group, ethnicity, and region.
These discourses and representations of the tradition are sometimes upheld or
even celebrated, while at other times, they may be challenged or subverted. One’s musical
identity is not necessarily expressed verbally, but is performed and demonstrated
musically. Repertoire and musical arrangements can be profoundly meaningful, representing a musician’s cultural values. The decisions of how to frame oneself within
the tradition influences how musicians relate to each other socially and professionally,
potentially having profound effects on issues such as intellectual property rights. In
addition, audio technology plays a significant role in how the tradition is presented,
understood, and experienced. Commercial recordings embrace socially constructed
notions of “liveness,” while live performances rely on amplification practices that connect
musicians to global popular culture while simultaneously upholding local musical
aesthetics.


identifier: Razeghin, Mehdi <https://research.library.mun.ca/view/creator_az/Razeghin=3AMehdi=3A=3A.html>   (2014) Preference-based web service composition.  Masters thesis, Memorial University of Newfoundland.


identifier: Williams, Jennifer <https://research.library.mun.ca/view/creator_az/Williams=3AJennifer=3A=3A.html>   (2015) Addressing multiculturalism in the Newfoundland and Labrador multiculturalism policy and in the everyday lives of Muslims in St. John's, NL.  Masters thesis, Memorial University of Newfoundland.

abstract:
Since 2005, the government of Newfoundland and Labrador has developed a number of
initiatives and social policies to increase immigration and improve immigrant retention.
At the same time, minority religious groups have grown, slightly increasing the
province's religious diversity. This thesis examines the 2008 provincial Multiculturalism
Policy alongside the experiences of Muslims living in St. John's to consider how
multiculturalism is lived within this particular context. Interviews with Muslims living in
St. John's capture experiences of multiculturalism outside of the context of government
policies and services. More concretely, the thesis focuses on the challenges faced by
Muslim participants in requesting religious holidays off from work. I conclude that,
although the existing provincial multiculturalism policy facilitates certain services and
programs, comprehensive issues like equal access to time off from work and school to
celebrate religious holidays could be better addressed. One step in this direction is a
broader definition of multiculturalism in the policy that might better define secularism
and more concretely address participants' challenges and concerns with religious
equality.


identifier: Mersereau, Joseph Montague <https://research.library.mun.ca/view/creator_az/Mersereau=3AJoseph_Montague=3A=3A.html>   (2015) Spatio-temporal changes in the distribution of benthic organisms at finfish farm sites on the south coast of Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract: In Newfoundland, assessing benthic community changes associated with organic matter enrichment near finfish farms is challenging because the majority of aquaculture sites are in deep waters, over hard, patchy substrata, where soft sediment sampling methods are ineffective. A promising approach is the use of video surveys to analyze epibenthic characteristics, including taxa that are indicative of organic matter enrichment, Beggiatoa spp. and OPC. Here, I compare seafloor biotic and abiotic characteristics on temporal and spatial scales over 2 years and at six locations. Benthic organisms and indicators were identified and evaluated in relation to distance to cage, aquaculture production status and environmental conditions. Abundance and percent cover of the benthos, with the exception of bio-indicators, was higher in non-production sites compared to the production and fallow sites, with minimal changes over time. Organic enrichment via aquaculture can lead to long term benthic changes (> 1 year) on hard substrata.


identifier: Martino, David <https://research.library.mun.ca/view/creator_az/Martino=3ADavid=3A=3A.html>   (2014) Mirror, mirror and the wall: seeing the problematics of doing reflection in the English language arts classroom as a gesture towards a minor literature of education.  Masters thesis, Memorial University of Newfoundland.

abstract:
In this thesis I propose that, as part of subjectifying processes operating within schools,
reflection in English Language Arts can be understood as both liberatory and/or enslaving
depending on the degree to which it orients students' experiences toward difference and
their own plural becomings or binds them within the confines of more limited ways of
knowing. Illuminating this distinction, I propose that we must begin our investigation
into reflection by examining the context within which it takes place. This context is not
neutral but rather actively participates in constructing the im/possibilities of student
reflection itself. I propose a distinction between school learning spaces and human
learning environments as a way to explore how discourse and our wider culture influence
reflection in theory and in my own experiences as a teacher. Attempting to move beyond
traditional limits, this thesis theorizes an/other understanding of reflection that situates
liberatory reflective practices in relation to ethics and social justice education.


identifier: Gundimeda, Naren K. <https://research.library.mun.ca/view/creator_az/Gundimeda=3ANaren_K=2E=3A=3A.html>   (2014) Analysis of key predistribution schemes in wireless sensor networks.  Masters thesis, Memorial University of Newfoundland.

abstract: Combinatorial designs are used for designing key predistribution schemes that are applied to wireless sensor networks in communications. This helps in building a secure channel. Private-key cryptography helps to determine a common key between a pair of nodes in sensor networks. Wireless sensor networks using key predistribution schemes have many useful applications in military and civil operations. When designs are efficiently implemented on sensor networks, blocks with unique keys will be the result. One such implementation is a transversal design which follows the principle of simple key establishment. Analysis of designs and modeling the key schemes are the subjects of this project.


identifier: McConnell, Sheri M <https://research.library.mun.ca/view/creator_az/McConnell=3ASheri_M=3A=3A.html>   (2015) What happens after children tell? a qualitative analysis of narratives of women who as children disclosed intra-familial sexual abuse.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Contrary to depictions of strangers and perverts lurking in the
shadows, most children are sexually abused by “normal” people known to
them, often in their own families. The majority of child sexual abuse, especially
when it occurs within families, is neither disclosed nor reported. It has been
argued that disclosure is a necessary prerequisite for protecting children and
ending abuse, as well as for child welfare, criminal, therapeutic, and other
individual and societal interventions. Although it opens the door for
intervention, disclosure is also a potential source of further trauma and
revictimization, depending on the responses to the disclosures.
There is a great deal of research addressing the prevention, prevalence
and incidence, antecedents, etiology, impact, disclosure, and treatment of child
sexual abuse. However, what appears to be lacking in the extant literature are
victim’s stories of what happened after they as children disclosed intra-familial
sexual abuse. Thus, 16 women living in Saskatchewan, Canada were
interviewed about their experiences of disclosing, before age 18, intra-familial
child sexual abuse. Employing feminist research methods and a constructivist
grounded theory research design, this research explores and describes the
process of disclosing, what happened after they disclosed, and how the abuse
ended. Two models for understanding disclosing and ending intra-familial
child sexual abuse and reactions to the disclosures are presented. The first reflects the factors impacting disclosing and ending abuse and the reactions of
families, community members, and professionals. The second envisions
optimal conditions for disclosing and ending intra-familial child sexual abuse,
and for achieving the desired responses to disclosures. Implicit within the
second model are recommendations for change, including implications for
professional practice and education.
This research is grounded in feminist, constructivist, and social work
traditions of witnessing individual subjective experiences and transforming
what is learned into individual and social change through social action. In
addressing concerns raised through women’s personal narratives, this research
aims to increase awareness and understanding among peers, families, formal
and informal support systems, and communities about how to respond
appropriately, supportively, and helpfully to children’s disclosures of sexual
abuse. Further, this research aspires to contribute to prevention, clinical
intervention, and child protection practices and policies, with an ultimate goal
of ending child sexual abuse.


identifier: Cahill, Farrell <https://research.library.mun.ca/view/creator_az/Cahill=3AFarrell=3A=3A.html>   (2015) Energy regulating hormones and the development of obesity and diabetes.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Obesity, a complex multifactorial disease, is a serious public health concern due to numerous obesity-related comorbidities thought to result from various hormones in combination with lifestyle and environmental factors. At present, the role of only a fraction of the hormones involved in obesity have been well defined. The aims of this thesis were to investigate: 1) the association of appetite regulating hormones with obesity and obesity-related phenotypes in the Newfoundland and Labrador general population; 2) the response and interaction of appetite and energy regulating hormones on obesity development under a positive energy challenge; 3) the association of dietary magnesium intake with obesity and diabetes; 4) testing the validity of the body adiposity index (BAI) in a Caucasian population; 5) the association of BAI with cardiometabolic risk factors (CRF); 6) and the development of a novel and more accurate equation than body mass index (BMI)and BAI to evaluate adiposity. All of these were achieved using data from two different studies - the large scale, population-based CODING (Complex Diseases in the Newfoundland Population: Environment and Genetics) study and an intervention-based, 7-day positive energy surplus study.
We have discovered that circulating PYY (appetite suppressant) is not significantly associated with obesity status defined by either percent body fat (%BF) or BMI. However, circulating PYY was influenced by age, smoking, medication use, and menopausal status in women. We also sought to explore the endocrine response of normal-weight, overweight and obese individuals to a 7-day hypercaloric diet. We demonstrated that PYY increased in response to overfeeding, but was not associated with changes in insulin resistance and/or weight. We also found that adiponectin (insulin sensitizer) was not associated with obesity status but the significant increase in adiponectin, due to overfeeding, was significantly associated with insulin resistance.
We also investigated the impact of dietary magnesium on obesity and obesity-related co-morbidities and found that higher dietary magnesium intake is associated with improved insulin sensitivity and this effect is particularly beneficial for overweight and obese individuals in the general population along with pre-menopausal women. Therefore, our data would suggest that the beneficial effects of magnesium intake are less sensitive among post-menopausal women.
In addition, we explored the applicability of the BAI and found that it was a better estimate of adiposity than BMI in the non-obese Caucasian population. The BAI was also more closely associated with the relationship of %BF with CRFs than BMI. However, this association is significantly attenuated when assessing the influence of increasing BAI on CRFs amongst men and women examined separately.
Lastly, we developed a sex-specific equation to overcome the gender related weakness of both BMI and BAI to predict adiposity. The body fat index (BFI) sex-specific equations we developed more accurately predict %BF than BMI and BAI in the general population and at various extremes of adiposity in men and women.


identifier: Bouzan, Stephen <https://research.library.mun.ca/view/creator_az/Bouzan=3AStephen=3A=3A.html>   (2015) The structure-property relationship of aryl-substituted tetrathiafulvalene vinylogues.  Masters thesis, Memorial University of Newfoundland.

abstract:
Tetrathiafulvalene (TTF) is well known in the discipline of materials chemistry for its
excellent electron donating properties. For decades, considerable efforts have been made to
design and synthesize novel -extended analogues of TTF (ex-TTFs) in order to exploit the
application in electronic and optoelectronic devices. Of the vast array of ex-TTFs known so far,
the class of vinylogous derivatives of TTF (TTFVs) has attracted the interest of many research
groups. TTFVs are ideal candidates for organic-based electronics as they have a low band gap
and rich electroactivity. This has posed the need to further investigate the interesting and
inherently peculiar nature of TTFV; in particular, the structure-property relationship that exists
with aryl based TTFVs has been a focus of this thesis work. Through the use of aryl substituents
conformational control of TTFV has been demonstrated. The use of a 1-naphthyl substituent
allowed a neutral TTFV to take an unprecedented trans conformation as a result of significant
allylic strain. Additionally, an unprecedented tricyclic S-containing heterocycle was produced
via ortho brominated aryl substituents. Finally, a group of alkynylated phenyl-TTFVs were
synthesized and characterized. The molecular properties of all the new TTFV and related
compounds have been studied by single crystal X-ray diffraction, UV-Vis absorption
spectroscopy, and cyclic voltammetry.


identifier: Habet, Jessica <https://research.library.mun.ca/view/creator_az/Habet=3AJessica=3A=3A.html>   (2014) Party outcasts: the underrepresentation of female parliamentarians in Belize.  Masters thesis, Memorial University of Newfoundland.

abstract:
Adding to the feminist literature on women’s underrepresentation in parliaments around
the world, this thesis presents Belize as an elucidative case. Primary and secondary data
were used to identify the barriers to women’s electoral success. Interviews were
conducted between May 2013 and February 2014 in Belize. An extensive review on
feminist literature outlined three types of barriers: (1) cultural; (2) structural; and (3)
institutional. The literature and primary data led to the conclusion that the largest barrier
in Belize is institutional where the political party is the critical gatekeeper to women’s
success.


identifier: Morrissey, Karla Anne <https://research.library.mun.ca/view/creator_az/Morrissey=3AKarla_Anne=3A=3A.html>   (2014) The role of the Ard1 protein in retinal endothelial cell permeability.  Masters thesis, Memorial University of Newfoundland.

abstract:
Tubedown (Tbdn) is a retinal homeostatic factor which is normally highly expressed in the retinal blood vessels which associates with the N-acetyltransferase Ard1. Tbdn also associates with Cortactin, a c-Src tyrosine kinase substrate. Downregulation of Tbdn correlates with neovascular retinal pathology in neovascular retinopathies. These diseases involve growth and hyperpermeability of retinal blood vessels leading to leakage of plasma proteins such as Albumin, inflammation and tissue damage. Knockdown of Tbdn in retinal endothelial cells results in co-suppression of Ard1, activation of c-Src/Fyn tyrosine kinase and increased permeability to Albumin. The focus of this study is to determine how Ard1 might regulate signaling pathways mediating the permeability of endothelial cells to Albumin as well as levels of phospho-Cortactin Tyr421 and activated c-Src/Fyn.
Ard1 was either knocked down using siRNA or overexpressed in RF/6A primate retinal endothelial cell line and the permeability to Albumin assayed. In parallel experiments, the activation status of components of the Albumin permeability pathway (phospho-Cortactin Tyr 421 and activated c-Src/Fyn) was monitored.
Ard1 knockdown reduced the permeability of the cells to FITC-Albumin but did not change the levels of phospho-Cortactin Tyr 421 or activated c-Src/Fyn when compared to controls. Cells transfected with the Ard1 expression vector overexpressed Ard1 and showed increased permeability of Albumin and increased levels of activated c-Src/Fyn compared to controls. Our results suggest that Ard1-mediated increase of activated c-Src/Fyn does not require Tbdn.


identifier: Shaik, Haseena <https://research.library.mun.ca/view/creator_az/Shaik=3AHaseena=3A=3A.html>   (2015) Di-thiafulvalene functionalized phenylene acetylene-polymers for selective dispersion of single walled carbon nanotubes (SWNTs).  Masters thesis, Memorial University of Newfoundland.

abstract:
This thesis explores the rational design, synthesis, characterization and
applications of conjugated polymers as carbon nanotube (CNT) dispersants. Two
Dithiafulvalene (DTF) functionalized Phenylacetylene based polymers were synthesized
using Sonogashira cross coupling conditions and Cu-catalyzed homo coupling conditions.
DTF unit was introduced by applying “click chemistry” to the side chain of the polymers
to form a “centipede-like” macromolecular architecture. The ability of synthesized
polymers to disperse SWNTs was tested in various organic solvents using UV-Vis,
photoluminescence Raman spectroscopic techniques, and SEM, AFM imaging.
Characterization results show, that dispersion is selective for small semiconducting (6,5),
(5,6), and (7,6) tubes. Furthermore, Hexane induced SWNTs release experiments were
under taken for the reversible dispersion process to attain “dispersant-free” SWNTs.
which could be turned into a very useful technique applicable in material preparation and
device fabrication where “additive-free” SWNTs are desired after solution-phase
processing (e.g., dispersion) in order to maximize electronic and/or optoelectronic
performances.


identifier: Wu, Feng <https://research.library.mun.ca/view/creator_az/Wu=3AFeng=3A=3A.html>   (2015) Emergent ontology discovered from folksonomies.  Masters thesis, Memorial University of Newfoundland.

abstract:
Collaborative tagging websites or systems allow users to associate freely-determined keywords (tags) with a particular resource. The collection of users’ tags and resources is referred to as a folksonomy. Unlike traditional forms of metadata, the meaning of, and relationships between, tags are not rigorously defined, limiting the usefulness of tag-based metadata. We propose a novel approach to enrich tagging systems by constructing a tag ontology that captures semantic relationships among tags. We first consider regularities that can be exploited in a folksonomy. Then, we show how user-level tag vocabulary can be used for tag meaning disambiguation. Following this, we introduce a distance model to calculate the relatedness of two sets of resources within a folksonomy, and use this to develop a method for discovering tag relations. A series of experiments we conducted demonstrate the effectiveness of the method. We conclude the thesis with example use cases where our method can be applied to improve folksonomy data organization and queries.

[illustration]


identifier: Newman, David Lorne <https://research.library.mun.ca/view/creator_az/Newman=3ADavid_Lorne=3A=3A.html>   (2012) The eschatology of Newfoundland and Labrador early Pentecostals: "Jesus is coming soon," 1910-1949.  Masters thesis, Memorial University of Newfoundland.

abstract: Eschatology is a core tenet of early Newfoundland and Labrador Pentecostalism. Advocates wove their belief in the imminent return of Christ and an impending apocalypse into periodical articles, correspondence, church decors, sermons, and songs. The Pentecostal Assemblies of Newfoundland and Labrador (PAONL) was influenced by the wider Premillennial, Holiness and Pentecostal movements as well as Newfoundland and Labrador's own religious traditions, especially those deriving from Methodism and the Salvation Army. The significant contributions of Holiness evangelist Alice Belle Garrigus, former Methodist minister Eugene Vaters, and other key leaders through the formative period, make their life and teaching vital to understanding the role eschatology played in the theology, spiritually and rhetoric of the movement. Throughout the 1910-1949 period Pentecostals interpreted historical events, societal challenges and their own ecstatic experiences that God had a special role for them to play on the cusp of the Second Coming of Jesus Christ.


identifier: Rietze, Amanda <https://research.library.mun.ca/view/creator_az/Rietze=3AAmanda=3A=3A.html>   (2015) Investigating geochemistry and habitability of continental sites of serpentinization: the Cedars, California, USA and the Tablelands, Newfoundland, CAN.  Masters thesis, Memorial University of Newfoundland.

abstract:
This study investigates the geochemistry and habitability of spring fluids associated with active continental serpentinization at The Cedars, California, USA and the Tablelands, Newfoundland, CAN. These ophiolite complexes were host to several springs discharging ultra-basic (>11) and highly reducing (<-400 mV) fluids rich in H2 gas that were geochemically distinct from the surrounding groundwater.
C2+ hydrocarbons at both ophiolite complexes suggest hydrocarbons were thermogenic in origin; however, an abiogenic contribution could not be ruled out. Methane at The Cedars was dominated by a microbial origin with a contribution of non-microbial sources, while methane at the Tablelands was dominated by a non-microbial source (i.e. thermogenic or abiogenic or mixture of the two). Spring fluids lacked electron acceptors and nutrients which adds further complications to the already unusually high pH and limited carbon fixation possibilities in this extreme environment.


identifier: Kouwenberg, Amy-Lee <https://research.library.mun.ca/view/creator_az/Kouwenberg=3AAmy-Lee=3A=3A.html>   (2014) Using feather corticosterone to assess the effects of non-breeding season conditions on breeding of Atlantic puffins (Fratercula arctica) and rhinoceros auklets (Cerorhinica monocerata).  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: In order to fully understand factors that affect animals during distinct parts of their annual cycle, it is important to consider that processes acting in one season may carry over to influence an individual’s success in the following season. Measuring conditions over multiple seasons and life history stages allows carry over effects to be identified and places an individual's current condition into a broader context. Corticosterone levels measured in blood reflect hypothalmic-pituitary-adrenal (HPA) activity in birds in response to challenges that threaten homeostasis. Circulating corticosterone is integrated into growing feathers and can provide physiological information about birds during times when they are unavailable for blood sampling. Here, we used a commercially-available enzyme immunoassay kit to measure corticosterone in alcid feathers, demonstrated the benefits of acetonitrile/hexane purification of samples, and showed that blood and feather corticosterone are biologically-meaningful, albeit non-identical, measures. We used our enzyme-immunoassay and purification method in tandem with stable isotope analysis to measure corticosterone and stable isotopes in feathers and blood collected from rhinoceros auklets Cerorhinca monocerata nesting on three widely-dispersed colonies during years with different oceanographic conditions. We found that individuals from different colonies could be distinguished by their δ15N and δ13C stable isotope values during, but not prior to the breeding season, and that corticosterone levels were consistent with this pattern. Furthermore, we found that rhinoceros auklets had significantly lower corticosterone levels in a year and on a colony assumed to have less favourable feeding conditions, which is opposite to results for other taxa. In a relative of the rhinoceros auklet, the Atlantic puffin Fratercula arctica, we found that egg mass increased in relation to female corticosterone and δ15N values in feathers grown in the months prior to breeding, indicating that physiological state of females prior to the breeding season can influence egg mass. In contrast, we found that pre-breeding corticosterone and δ15N values of rhinoceros auklet females were not correlated with egg mass or egg protein levels (pilot study). Overall our results support our hypotheses that corticosterone levels vary with environmental conditions and that differences in corticosterone levels during pre-breeding correlate with egg size in the subsequent season (breeding). However, our results also indicate that interpreting these relationships requires careful consideration of ecological and physiological characteristics of the individual or taxa in question.


identifier: El-Darymli, Khalid <https://research.library.mun.ca/view/creator_az/El-Darymli=3AKhalid=3A=3A.html>   (2015) Holism for target recognition in synthetic aperture radar imagery.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Reductionism and holism are two worldviews that underlie the fields of linear and
nonlinear signal processing, respectively. In the reductionist worldview, deviation from
linearity is seen as a noise that warrants removal. In the holistic worldview, the
system is viewed as a whole that cannot be fully understood solely in terms of its
constituent parts. Conventional radar resolution theory is a direct application of the
reductionist view. Consequently, analysis of single-channel synthetic aperture radar
imagery for automatic target recognition (SAR-ATR) has traditionally been based
on linear techniques associated with the image intensity while the phase content is
ignored. The insufficiency of the linear system theory to extended targets has been
empirically observed in the literature.
This thesis consists of a development of novel tools that exploit the nonlinear phenomenon
in focused single-channel SAR imagery and application of these tools to the
SAR-ATR problem. A systematic procedure to infer the statistical significance of the
nonlinear dynamics is introduced. Furthermore, two novel frameworks for feature extraction
from complex-valued SAR imagery are presented. The first framework is solely
based on the often ignored phase content, and it is built on techniques from the fields
of complex-valued and directional statistics. The second framework utilizes complexvalued
SAR imagery and provides for exploiting nonlinear and nonstationary signal
analysis methods based on the Poincaré and Hilbert views for nonlinear phenomena.
Using real-world SAR datasets, the overall results confirm the statistical significance of
the nonlinear effect for the case of extended targets. Furthermore, when the complexvalued
SAR image is detected, the nonlinear dynamics are found to be obliterated or
greatly altered. The efficacy of the frameworks developed is clearly demonstrated.


identifier: Pedersen, Mette Rode <https://research.library.mun.ca/view/creator_az/Pedersen=3AMette_Rode=3A=3A.html>   (2015) Short-term changes in biochemical parameters following laparoscopic sleeve gastrectomy in patients from the Newfoundland & Labrador bariatric surgery cohort study.  Masters thesis, Memorial University of Newfoundland.

abstract:
Background Biochemical abnormalities associated with micronutrient status and non-alcoholic fatty liver disease (NAFLD) are often observed prior to bariatric surgeries, and the changes following surgery can be associated with either improvements or worsening. However, evidence on these changes following laparoscopic sleeve gastrectomy (LSG) is limited.
Purpose The purpose of this quasi-experimental study was to determine the baseline status of certain biochemical parameters associated with micronutrient status and NAFLD prior to LSG and compare them to the status post-LSG.
Methods A total of 188 patients, who underwent the LSG procedure between May 2011 and May 2014, consented to partake in this study. Laboratory measurements of select biochemical parameters associated with micronutrients (25-hydroxyvitamin D, PTH, vitamin B12, calcium, ferritin, hemoglobin and mean cell volume) and NAFLD status (bilirubin, ALP, ALT, GGT, HDL, LDL and triglycerides) were assessed at baseline and re-evaluated at 3 and 6 months post-LSG.
Results A subgroup consisting of 95 patients were included in the current thesis, as they had completed their baseline, 3 and 6 months evaluations. 82.1 % of patients were female with a mean BMI of 49.3 ± 6.8 kg/m2. At baseline, 53 patients (55.8 %) presented with abnormal blood levels for the micronutrient-related parameters, and there was a non-significant decrease to 50.5 % and 46.3 % at 3 and 6 months post-LSG, respectively. Prior to surgery, the most common abnormalities were elevated PTH and low 25-hydroxyvitamin D (25-OH-D). The majority of the micronutrients and related parameters did not change significantly following LSG. A significant reduction in the proportion of patients with low 25-OH-D was observed, from 21.3 % at baseline to 1.4 % (1 patient) at the 6-month follow-up (p < 0.001), which may be attributed to increased supplement use. The majority of patients (80 %) presented with abnormal blood levels for one or more of the select parameters associated with NAFLD at baseline, the most common being abnormal GGT, triglycerides, HDL, LDL and ALT. There was a significant improvement post-operatively, with 60 % and 50.5 % of patients at 3 and 6 months post-LSG, respectively, presenting with abnormal levels for the select biochemical parameters (p < 0.001).
Conclusion Patients experienced an improvement in 25-OH-D post-LSG, which may have been attributed to increased use of supplements. An improvement in the majority of the biochemical parameters associated with NAFLD was also observed. The overall improvements observed may also be attributed to the significant weight loss following LSG.


identifier: Shadadeh, Mohammad <https://research.library.mun.ca/view/creator_az/Shadadeh=3AMohammad=3A=3A.html>   (2015) Up-scaling relative permeability for stratified reservoir waterflooding.  Masters thesis, Memorial University of Newfoundland.

abstract:
This research presents an improved procedure for generating pseudo relative
permeability curves for stratified waterflooding using either constant pressure
or constant flux at the reservoir boundaries. Pseudo relative permeability
reflects the generation of a relative permeability curve that can be used to represent the
entire reservoir thickness, rather than a specific layer during reservoir simulation, thus
saving computational time.
In this project, Fractional Flow Theory is applied to the generation of pseudo relative
permeability curves for i) constant flow rate condition, and ii) constant pressure boundary
condition. Previously pseudo relative permeability curves were generated for the constant
flow rate condition only. The method differs from previous methodologies and studies,
which are all based on a piston-like displacement for water flooding. Instead, this new
model uses fractional flow theory to generate a pseudo relative permeability curve that is
physically more realistic. The solution is extended to generate pseudo relative permeability
curves for simulating the waterflood of a reservoir under the constant pressure boundaries
which is a more realistic assumption in compared to constant flow rate. The generated
pseudo relative permeability curve is used in a 2D areal reservoir model in an ECLIPSE
simulator to predict the behavior of the full layered 3D reservoir model. It was found that
there is good agreement between the results corresponding to this new method and the full
layered reservoir model, which is very important.


identifier: Puckrin, Olivia Anne <https://research.library.mun.ca/view/creator_az/Puckrin=3AOlivia_Anne=3A=3A.html>   (2015) Incidence of sib mating, test for inbreeding depression and potential application for reducing the impact of escaped cultivated cod on wild Atlantic cod (Gadus morhua).  Masters thesis, Memorial University of Newfoundland.

abstract:
Fish often escape from aquaculture operations raising concerns of interactions
with wild individuals. Due to selective breeding and high fecundity among Atlantic cod,
few breeding individuals are used in culture, potentially leading to inbreeding among the
offspring within the cages. If inbreeding among Atlantic cod reduces offspring survival,
this could limit the risk of outbreeding depression from cod escaping as eggs or larvae,
maturing and mating with wild cod. To determine if cod inbreed and what effects
inbreeding has on offspring, spawned embryos from tanks of sister−brother−unrelated
male trios underwent microsatellite analysis to determine parentage. Inbreeding occurred
with no significant bias toward one type of male. Percent hatch, deformities, larval size,
and mortality were monitored in artificially fertilized inbred and unrelated crosses. Only
percent hatch differed significantly, being higher in non-inbred offspring (P = 0.024). One
generation of inbreeding is not sufficient to determine if inbreeding would effectively
reduce farmed cod offspring survival.


identifier: Hennessey, John C. <https://research.library.mun.ca/view/creator_az/Hennessey=3AJohn_C=2E=3A=3A.html>   (2015) Effect of proteinase-activated receptor 2 activating peptide, 2-furoyl-LIGRLO-amide, on murine mesenteric endothelial cell Ca²⁺-events.  Masters thesis, Memorial University of Newfoundland.

abstract: Proteinase-activated receptor 2 (PAR2)-mediated elevations of cytosolic Ca²⁺, induced by PAR2 agonist 2-furoyl-LIGRLO-amide (2fly), have been demonstrated in cell culture experiments. The properties of individual PAR2-mediated Ca²⁺-events in endothelial cells (EC) have yet to be described, and the role that these Ca²⁺-events play in the preservation of PAR2-mediated vascular reactivity in endothelial dysfunction is not understood. Male C57BL/6J (PAR2-WT) and PAR2 knockout (PAR2-KO) mice were implanted with sub-cutaneous micro-osmotic pumps containing either saline (control) or angiotensin II (endothelial dysfunction). Doses of angiotensin II were 1.5 mg/kg/day, control pumps were filled with 100 μl of saline. Imaged under spinning disk confocal microscopy, Fluo-4 loaded Ang II-treated ECs exhibited 21% and 23% attenuation in the density of ACh-evoked muscarinic (M₃)-mediated, Ca²⁺-events in PAR2-WT and PAR2-KO, respectively. 2fly-mediated Ca²⁺-events were unaffected by Ang II treatment. The density of Ca²⁺-release sites were reduced by IP3R inhibition using xestospongin-C and TRPV channel inhibition using ruthenium red. This study identified two populations of non-propagating Ca²⁺-events in murine mesenteric ECs: small peripheral and large-repeating transients. The study concluded that PAR2 Ca²⁺-signaling is preserved in the presence of endothelial dysfunction. Immunocytochemistry experiments of fixed and permeabilized ECs, on a line-scan confocal microscope, revealed that the distribution of eNOS was significantly attenuated with Ang II treatment. This reduction of eNOS in Ang II-treated ECs may contribute to the attenuation of resistance vessel relaxation in endothelial dysfunction.


identifier: Gao, Qian <https://research.library.mun.ca/view/creator_az/Gao=3AQian=3A=3A.html>   (2015) Development of laboratory and field drilling tools to measure bit operating conditions and drill string motions.  Masters thesis, Memorial University of Newfoundland.

abstract:
The advanced drilling laboratory (ADL) has been developing a Vibration Assisted Rotary Drilling (VARD) System for several years, which is used for seeking the advantages brought by combining drilling bit vibration and rotation together in drilling operation. In order to achieve the laboratory and field data acquisition and processing several integrated data acquisition systems are necessary. These systems are based on the most suitable sensors, acquisition parameters, and software to monitor different bit operating conditions and drill string motions in different experiments.
The laboratory and field measurement systems include i) the control system of a Small Drilling Simulator (SDS), ii) a Mobile Data Acquisition system for field experiments, and iii) a Down Hole Measurement Tool, or Sensor Sub for drilling field trials.
The system for the SDS is based on the LabVIEW programming language and includes the data acquisition, processing and system control ability. In this system, the LabVIEW user interface allows the operator to perform data acquisition, processing and logging.
The Mobile data acquisition (DAQ) system is an extension of the SDS system based on the Signal Express Program and includes data acquisition and processing. It was designed to be able to be carried and operated in tough environments and has numerous data acquisition configurations for a range of different experimental requirements.
The Down Hole Measurement Tool (Sensor Sub) is based on the use of accelerometers and magnetometers, along with onboard data acquisition and battery power systems; it is designed to operate in the down-hole environment with high temperature, high pressure and severe vibration to supply raw data for each drilling experiment. The field trial results show that the Sensor Sub can provide compatible and accurate data to identify drill string motions (including rotary speed and bit orientation), and bit vibrations (including axial lateral torsional and bit whirl).


identifier: Williams, Kerry-Lynn M. <https://research.library.mun.ca/view/creator_az/Williams=3AKerry-Lynn_M=2E=3A=3A.html>   (2015) An iterative synthetic route toward pyrenophane chains.  Masters thesis, Memorial University of Newfoundland.

abstract:
The use of pyrene as a building block for molecules with applications in optoelectronic
devices is becoming increasingly important.1 In this regard, the development of
methodologies that provide convenient and highly regioselective access to functionalized
pyrenes will facilitate progress in this area. For example, the Bodwell group at Memorial
University recently showed that the placement of alkoxy groups at the 4 and 5 positions
on pyrene (e.g. 1) both activates the pyrene system towards electrophilic substitution and
effectively hinders the 3 and 6 positions. This methodology has been used in the
synthesis of (1,8-pyrenylene)-ethynylene macrocycles,2 and is now at the heart of an
iterative five-step strategy aimed at the synthesis of oligomeric pyrenophanes 2, 3 and
beyond. Details of the synthetic approach toward these pyrenophane chains will be
presented.

[illustration]


identifier: Li, Yan <https://research.library.mun.ca/view/creator_az/Li=3AYan=3A=3A.html>   (2014) Characterization and crystallization of chiral aromatic amino acids.  Masters thesis, Memorial University of Newfoundland.

abstract:
The aromatic amino acids play a vital role in both biology and pharmacology areas. On one hand, they are the essential building blocks of protein, which can carry out many crucial bodily functions. On the other hand, these substances are recognized as chiral drugs containing a racemate and two enantiomers. In addition, the special aromatic ring adds a complex structure to this kind of amino acids. As a result, the investigation of the aromatic amino acids gains great significance and can provide people some practical ideas in the researching works about protein.
This thesis presents a comprehensive study on the characterization and crystallization of aromatic amino acids. In the first part, diverse recognition methods were applied to characterize the L-tryptophan (L-Try), such as X-ray single crystal and powder diffraction analyses, differential scanning calorimetry, as well as measurement of solid-liquid equilibrium in water/isopropanol solution. The absence of eutectic point was demonstrated by the binary melting point diagram  and the ternary phase diagram, which indicated the existence of a pseudoracemate (i.e., solid solution). The racemate, enantiomers, and the mixtures of them gave the identical powder X-ray diffraction patterns, and the X-ray single crystal analysis showed that the racemate and enantiomers of tryptophan gained very similar solid-state packing geometries, which confirmed the conclusion above. As a result, all the thermodynamic and crystallographic analyses have supported the conclusion that the tryptophan crystallized as a pseudoracemate.
The second part of this thesis mainly focused on the study of the effect of tailor-made impurity on the crystallization process. The influences of L-tyrosine (L-Tyr) on the solubility, crystallization kinetics, and polymorphism of L-Phenylalanine (L-Phe) were respectively investigated. The results indicated that the presence of L-Tyr could increase the solubility and the crystal nucleation rate of L-Phe in water, however, the growth of L-Phe on a certain direction would be suppressed and thus the formation of polymorphs became unavoidable. Specifically, the addition of L-Tyr could make the anhydrate form of L-Phe more stable at 24ﾟC.


identifier: Moore, Allison Catherine <https://research.library.mun.ca/view/creator_az/Moore=3AAllison_Catherine=3A=3A.html>   (2015) The geological reservoir characterization of a calcite-cemented, heterolithic shoreface reservoir, Ben Nevis formation, Hebron Asset.  Masters thesis, Memorial University of Newfoundland.

abstract:
Depositional and diagenetic heterogeneities control reservoir quality and
performance and a better understanding of their distribution and impacts on fluid
flow will improve reservoir development planning and maximize hydrocarbon
recovery. Shoreface deposits within the Ben Nevis Formation at the Hebron Asset
consist of alternating beds of facies with contrasting reservoir quality that are
diagenetically overprinted with the precipitation of calcite cement. Lower quality
fairweather facies are interbedded with higher quality sandstone beds that record
periodic pulses of sediment into a quiescent shoreface environment by storm activity.
The heterolithic nature of the reservoir and diagenetic alterations caused by calcite
cement have implications on reservoir continuity and the spatial distribution of
reservoir properties that control fluid behaviour. It is difficult to understand and
quantify this distribution from subsurface data alone, and outcrop analogue studies
aid in reservoir characterization and modelling by revealing information at the
interwell-scale about facies architecture, continuity and distribution. An outcrop
study of cemented shoreface parasequences in the Book Cliffs, Utah quantified the
dimensions and distributions of calcite concretions and calculated variograms with a
horizontal:vertical anisotropy ratio of 5:1. This ratio was used in the stochastic
population of facies in the Hebron reservoir model to calculate horizontal variograms
from vertical variograms that are well-defined from well log data. Streamline
simulation demonstrates the importance that a geologically-realistic representation of
cementation has on reservoir performance. Streamlines indicate that concretions act
as baffles, making flow paths more tortuous and causing earlier breakthrough.


identifier: Aktas, Oktay <https://research.library.mun.ca/view/creator_az/Aktas=3AOktay=3A=3A.html>   (2008) Raman spectra of the B mode of the ferroelastic compound Rb₄LiH₃(SO₄)₄ as a function of temperature.  Masters thesis, Memorial University of Newfoundland.

abstract:
Raman scattering measurements were performed on the ferroelastic compound Rb₄LiH₃(SO₄)₄
to determine whether the phase transition at Tc = 132 K is proper or pseudoproper ferroelastic.
A double grating spectrometer was used to measure the frequency of the Raman
active B mode at 31 cm⁻¹ in Rb₄LiH₃(SO₄)₄ as a function of temperature using two different
scattering geometries. Right-angle measurements were performed between 20 K and 295
K whereas the temperature range for back scattering measurements was from 60 K up to
285 K.
Our Raman measurements reveal that the square of the frequency of the optical B mode
at 31 cm⁻¹ shows two linear temperature dependencies corresponding to temperatures above
and below Tc. This behavior has been analyzed using a pseudoproper ferroelastic Landau
Model which accounts well for the temperature dependence of a soft optical mode. Our
Raman investigation clearly indicates that the nature of the ferroelastic phase transition in
Rb₄LiH₃(SO₄)₄ is pseudoproper ferroelastic.


identifier: Aktas, Oktay <https://research.library.mun.ca/view/creator_az/Aktas=3AOktay=3A=3A.html>   (2012) Investigation of magnetoelastic coupling in multiferroic geometrically frustrated magnets: CuFeO₂, CuCrO₂, and CuCrS₂.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Elastic and structural properties of triangular lattice antiferromagnets CuCr0₂ , CuFe0₂ ,
and CuCrS₂ were investigated to elucidate the role played by spin-phonon coupling in the
magnetic and multiferroic properties of a large class of triangular latt ice antiferromagnets.
Using Brillouin scattering, five of six elastic constants of CuCr0₂ are determined at room
temperature. Low temperature elastic properties of CuCr0₂ are extensively investigated with
the ultrasonic pulse echo method. According to these measurements, the elastic constants
C₁₁, C₄₄, and C₆₆ show softening as the temperature is reduced down to the antiferromagnetic
transition temperature Tn₁ = 24.3 K. The Landau analysis of the ult rasonic data indicates
a first order pseudoproper ferro elastic transition at T n₁ , where magnetic moments can act
as a secondary order parameter. The transition corresponds to a structural change from the
tetragonal point group 3m to the monoclinic point group 2/m. In addition, the symmetry
lowering at Tn₁ seems to aid the spin-driven ferroelectricity below Tn₂ = 23.8 K, at which
the crystal symmetry should change from 2/m to 2. The existence of Tn₂ is confirmed by
simultaneous measurements of the dielectric constant E[uo) and acoustic modes.
Unlike CuCr0₂ , isostructural CuFe0₂ seems to show a second order 3m -'- 2/m ferroelastic
transition coincident with the antiferromagnetic transition at Tn₁ = 14 K [1] . In
order to confirm if the t ransition is second order, Brillouin scattering measurements were
performed on CuFe0₂ . Due to the opacity of CuFe0₂ , Brillouin spectra show only surface
acoustic modes for waves propagating in the xy and xz planes. The velocity of the modes depends on the elastic constants c₄₄ and c₃₃ .
Raman measurements were performed to possibly determine if the ferroelastic transitions
at Tn₁  in CuFe0₂ and CuCr0₂ and the R3m ---> Cm structural and antiferromagnetic
transition at TN = 38 K in another geometrically frustrated magnet, CuCrS₂, are driven
by a soft optic mode. Based on these measurements, the temperature dependencies of
all modes in CuCr0₂, CuFe0₂ and CuCrS₂ are attributed to anharmonic phonon-phonon
interactions. Therefore, Raman modes in CuCr0₂ and CuFe0₂ cannot account for the
ferroelastic transit ions observed at Tn₁ , leaving the driving mechanism of the ferroelastic
transit ions uncertain. Similarly, measurements on CuCrS₂ does not reveal any soft optic
modes.
Finally, simultaneous measurements of the dielectric constant and acoustic velocities of
CuCr0₂ were performed to determine the magnetic phase diagram of CuCr0₂ for magnetic
fields along the [110] and [l10] directions (hexagonal setting). For magnetic fields parallel to
the [110] direction the dielectric constant and acoustic modes show an anomaly at Hflop ~5
T between 2 K and 23.7 K, which correspond to a 90° flop in the spin-spiral plane and electric
polarization. The anomaly observed in the longitudinal acoustic mode propagating in the
basal plane is attributed to the field dependence of magnetic susceptibility. Measurements
performed with magnetic fields parallel to the [110] direction suggest a reorientation in the
spin-spiral plane.
The ferroelastic transition, coincident with the antiferromagnetic transition at Tn₁  in
CuCr0₂ as well as acoustic anomalies at the spin flop transition clearly indicate that magnetoela.
stic coupling has a. strong impact on the magnetic and multiferroic proper ties of
CuCr0₂. For a complete understanding of the role of magnetoelastic coupling on these
properties in CuCr0₂ and a. large class of triangular lattice antiferromagnets, results on the
ultrasonic velocity measurements on CuCr0₂ have to be analyzed using a Landau model that
includes magnetoela.stic coupling terms as well as the coupling between the order parameter and magnetic moments.


identifier: Adegoke, Adeolu O. <https://research.library.mun.ca/view/creator_az/Adegoke=3AAdeolu_O=2E=3A=3A.html>   (2015) Heteroclitic human immunodeficiency virus peptides enhance HIV-specific CD8⁺ T cell proliferation and reduce PD-1 expression.  Masters thesis, Memorial University of Newfoundland.

abstract:
Heteroclitic peptides are sequence variants of native peptide epitopes that stimulate T
cell responses superior to the native epitope. Since heteroclitic peptides enhance HIVspecific
CD8⁺ T cell cytokine production, we investigated whether they reduce signs
of HIV-specific CD8⁺ T cell exhaustion. Twenty-four variant peptides were generated
from reference human histocompatibility-linked leukocyte antigen (HLA)-A2-
restricted peptide epitopes Nef 8391, Nef 135143, Gag 433440 and Gag
7785 with conservative and semi-conservative amino acid substitutions at positions
3, 5 and 7 or 3, 5 and 8 of Gag 433440. Variants that enhanced interferon-gamma
(IFN-γ) and/or interleukin-2 (IL-2) production were tested for their effects on
proliferation and programmed death-1 (PD-1) expression. Heteroclitic variants
enhanced HIV-specific CD8⁺ T cell proliferation by > 20% in 13/29 cases, induced
lower PD-1 expression by 15% - 50% in 10 cases, and by ≥ 50% in 3 cases. These
data indicate unique immunotherapeutic potential for heteroclitic peptides.