identifier: Wang, Xuan <https://research.library.mun.ca/view/creator_az/Wang=3AXuan=3A=3A.html>   (2022) Naodongfang: an examination of meanings in Chinese wedding games and pranks.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
This doctoral dissertation in Folklore explores a traditional, widespread wedding custom
in China known as Naodongfang. When used generally, the term “Naodongfang” refers to the
scope of all jokes, pranks and games played by grooms, brides, groomsmen, bridesmaids,
parents, parents’ siblings and relatives during Chinese weddings. Although the custom has a long
history, stretching back 2000 years, today many Chinese citizens consider its elements, such as
beating grooms, humiliating brides and bridesmaids, and encouraging fathers-in-law and brides
to hug and kiss each other, as bizarre, inappropriate, and even malicious. In this study I attempt
to answer the questions: “Why is Naodongfang active in China today?” and “What are
Naodongfang’s meanings?” I draw on published descriptions and analyses as well as my own
ethnographic materials to explore economic meanings; discuss connections to Chinese concepts
such as the Golden Mean, Propriety, and female reservedness; and examine Nao culture in the
context of the carnivalesque. A significant focus of the thesis is the exploration of gender issues
and violence associated with Naodongfang. Reports of injuries, sexual harassment, and sexual
assault experienced by both female and male participants have made the custom controversial.
Thus, the last three chapters explore connections of Naodongfang with Chinese feminism,
patriarchy and constructions of masculinities.
My intention is not to argue whether Naodongfang is good or bad. Rather, I hope this
thesis provides new ethnographic materials and analyses on Naodongfang in a way that
contributes to a larger conversation of wedding games and pranks and their deeper meanings. I
argue that although this custom is criticized and stigmatized by many, it still holds value for
some individuals and their communities. These meanings are multifaceted. Naodongfang allows
participants to laugh and joke and to step out their everyday lives. This liminal time, with its
freedom from usual decorum, can bring participants together or it can pit them against each other
as guests compete for red packets or exert pressure on, or exact revenge against, the bridal couple
or bridal party. Although Naodongfang can feel like an act of resistance towards authorities, it
also reinforces existing family and clan power structures, as well as gender stereotypes, and
promotes heteronormativity.


identifier: Fitzgerald, Justin <https://research.library.mun.ca/view/creator_az/Fitzgerald=3AJustin=3A=3A.html>   (2022) Formerly the HMCS Labrador: an analysis of the vessel transfer that removed the Royal Canadian Navy from the Canadian Arctic.  Masters thesis, Memorial University of Newfoundland.

type: Thesis NonPeerReviewed

abstract: This paper explores the question why the HMCS Labrador, an effective, valuable icebreaker and the first to be commissioned by the Royal Canadian Navy, was decommissioned in 1958 after less than four years of military service. The reasons for this are often described as "budgetary considerations"; However, it is conspicuous that the Navy would reverse its defence policy so radically and decommission its only vessel capable of arctic patrol and exploration, having so recently identified a weakness in Arctic capabilities. Foreign policy decision making theory is applied to investigate the personal backgrounds and structural constraints influencing those who participated in the decision-making process, and better understand their personal motives in an organizational context. This analysis reveals that based on Canadian defence commitments abroad and the budget cuts of a new Conservative government, the most likely future outcome of the HMCS Labrador was decommission. Yet, the findings speak to a pattern in Canadian post-war defence policy, where Canada’s Navy struggled to articulate its role in the world other than through its responsibilities to NATO, and thereby more closely linking itself with the US.


identifier: Sheppard, Amy <https://research.library.mun.ca/view/creator_az/Sheppard=3AAmy=3A=3A.html>   (2022) “You have to want it:” women’s desistance processes in a short-term provincial prison.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
My research examines how provincially sentenced women in Newfoundland and Labrador engage in the desistance process when imprisoned and released into the community. Desistance is the cessation of criminal behaviour. There remains a lacuna in knowledge tied to understanding how women’s experiences both within and outside prisons shape their ability to engage in crime-free living after the experience of prison. Thus, I focus on women’s cognitive shifts toward desistance and services that may help with the desistance process. Furthermore, I examine the impacts of mental disorders and addiction on women’s desistance processes.
To examine formerly incarcerated women’s processes of desistance, I have interviewed 17 formerly incarcerated women and 16 service providers who work with them. Women interviewed for this study shared their reentry experiences into the community and recommendations to improve the reentry process for other women leaving prison. Furthermore, they share how release from prison into the community informed their ability to engage in desistance. Additionally, formerly incarcerated women share how experiences of being in prison, including accessing services offered, impact their decision and ability to engage in desistance.
Service providers have experience working within systems and with a heterogeneous population of women and thus have valuable knowledge that furthers discussion around women’s desistence processes. Service providers share their experience of working with criminalized women in prison and on release. They elucidated systemic barriers that hinder women’s ability to engage in desistance after release from prison,
My core research questions are: How do incarcerated women in Newfoundland and Labrador plan to make changes in their lives after prison? What do women interpret as the
impacts of addiction on their ability to make changes or, simply put, desist? I seek to understand (i) if released women are informed about services that met their unique needs (i.e., substance use histories, mental health concerns, childcare issues), (ii) if they feel able to reach out to such services, (iii) and if they feel that using services will help achieve goals of desistance (if they have such goals of course). To understand women’s lived experiences and, thus, the role of prison in shaping their interpretation of their possible post-prison experiences, I include an analysis of the services/supports available to women, both in prison and after their release in Newfoundland and Labrador.
Key findings consist of several factors impacting women’s ability to engage in the desistance process. These include connections between desistance and drug use whereby formerly incarcerated women see their drug use as interconnected and entwined with their criminal activity. Women and service providers assert that basic needs, such as safe housing, must be met to promote desistance from crime. Stigma impacts the desistance process due to the relational nature of desistance. The desistance process requires that others see that an individual has started to change and move away from criminal activity and towards a pro-social lifestyle. Furthermore, stigma impacts practical elements of desistance, such as the ability to obtain housing and employment,
To support the desistance process for criminally involved women leaving prison in NL, service providers must support both the cognitive processes (individual work) and advocate making systemic changes. The process of desistance is rooted in an individual’s desire to make changes. These changes occur within a social context that impedes many women’s ability to successfully and smoothly move toward desistance


identifier: Nemani, Shreya <https://research.library.mun.ca/view/creator_az/Nemani=3AShreya=3A=3A.html>   (2022) A species- and traits-based approach to predictive mapping of the distribution and diversity of costal benthic assemblages.  Masters thesis, Memorial University of Newfoundland.

abstract: Maps of seafloor habitats are important for managing marine areas as they delineate distinct regions of the seabed based on their bio-physical characteristics. Spatially continuous sonar-derived bathymetry and backscatter data, and derivative terrain and textural features are used to predict the distribution of species and communities. Various technical and conceptual methods have been recommended to develop more accurate and informative habitat maps. In support of current literature recognizing the importance of scale in determining species occurrence, Chapter 2 recommends a feature selection method for studies using multiple scales to calculate geomorphic features. Based on this information, full-coverage habitat maps of species assemblages across two coastal sites are predicted. Additionally, Chapter 3 proposes biological traits analysis (BTA) to assess the functional composition of species assemblages, and models continuous maps depicting the spatial distribution of taxonomic and functional diversity metrics. Since current methods to develop habitat maps mainly use a taxonomic approach based on species community composition, a functional traits-based approach assessing a species’ behaviour, life-history, and morphology provides a stronger link to broader ecosystem functions for the region. Together, these results are complimentary and provide spatially explicit management tools to support evidence-based decision-making in a changing marine environment.


identifier: Abdulihak, Mohammed <https://research.library.mun.ca/view/creator_az/Abdulihak=3AMohammed=3A=3A.html>   (2021) Distributed collision avoidance and object sorting for robot swarms.  Masters thesis, Memorial University of Newfoundland.

abstract:
A robotics swarm is a set of simple distributed agents cooperating to achieve a
certain goal. Each robot works independently of the others based on its own local
knowledge without any central coordination. These systems are often inspired by
social insects which work collaboratively to perform complicated tasks such as sorting
their brood or waste in certain patterns through local interactions. Swarm robotics
take inspirations from these natural phenomena to design scalable and robust systems.
The work in this thesis can be divided into two main objectives. The first is a
general purpose distributed collision avoidance algorithm that enables multiple robots
to seamlessly share their environment without colliding or blocking each other's paths.
The proposed algorithm is very fast with O(n) complexity and only requires relative
positions of neighboring robots. It also has special mechanisms for early deadlock
prediction and recovery to prevent robots from getting stuck.
The second objective is proposing a distributed sorting algorithm. It builds upon
the previous algorithm, which guarantees collisions avoidance and minimizes deadlocks
while driving the robots to their goals, and incorporates the ability for a robotic
swarm system to cooperatively sort a collection of objects from different classes into
desired areas for each class.
The design and implementation of this swarm system on a simulation platform
and on physical robots will be detailed. A web-based multi-robot simulation platform
is developed as a general robotics simulation and will be used to evaluate the different
algorithms in our system. We will also showcase and evaluate the proposed swarm
system by deploying these algorithms on actual robots.


identifier: Hamoda, Mahmoud <https://research.library.mun.ca/view/creator_az/Hamoda=3AMahmoud=3A=3A.html>   (2022) Modeling pressure drop and heat transfer in plate heat exchanger channels.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
In compact heat exchangers, surface enhancements have been used for augmenting heat transfer due to the growing urgency for energy conservation and reduced environmental impact. Plates with corrugated walls are utilized in plate heat exchangers (PHEs) as they increase the effective heat transfer area, disrupt and reattach the boundary layer, and promote swirl flow resulting in a compact heat exchanger with high heat transfer performance. As a result, their applications have grown considerably to include a wide range of industries and processes, such as food, pharmaceutical, power generation, cooling engine oil, and dairy product processing. Due to heat exchanger size constraints, a compact heat exchanger's flow passages are often short in the automobile industry, especially for cooling engine oil and transmission oil. Hence, the heat exchanger is likely working with developing flow characteristics that have higher heat transfer and pressure drop compared to developed flow.
A review of the open literature reveals a gap in the knowledge regarding the influence of the channel length on the thermal-hydraulic performance of PHE, which needs additional research. Also, no general models or correlations have been developed for predicting heat transfer and pressure drop in the entrance region of PHEs. Therefore, this thesis aims to experimentally investigate the effect of the channel length on the thermal-hydraulic performance of PHEs and to develop models for use in predicting pressure drop and heat transfer of PHEs, including the entrance region.
An experimental facility is constructed to perform a series of single-phase flow tests
on pressure drop and heat transfer of chevron PHE with two different channel lengths, 20.3 cm and 10.1 cm, and three different chevron angles, 30°,45°, and 60°. Mineral oil and water are used as the working fluids to cover laminar and turbulent flow regions. The results show that plates with a higher chevron angle experience higher pressure drop and heat transfer, which is consistent with the literature. Furthermore, the results of the effect of channel length on the Nusselt number of a PHE are very interesting as they demonstrate a significant impact of channel length on heat transfer performance of PHEs. The Nusselt number for short channels is considerably higher than for longer channels, indicating that thermal entrance effects are present. In addition, the Fanning friction factor results show that it is independent of the channel length at very low Reynolds numbers, while it is greatly impacted by the length of the channel at higher Reynolds numbers. The significance of these findings is that PHE channel length is an important factor that needs to be considered; however, it is often neglected due to assuming fully developed flow. This is important when designing a PHE and/or developing general models or correlations to predict the thermal and hydraulic performance of the PHE to cover a wide range of the Reynolds numbers. It is especially significant for applications where the length of the heat exchanger's flow passage is constrained.
Finally, models for predicting the Fanning friction factor and Colburn factor are developed, which are a function of the plate length, corrugation depth, chevron angle, and Reynolds number. Agreement between the proposed models and the present experimental data is within ±20%. These models are also validated against numerical and experimental data from the literature and show good agreement within ±20% in most cases within the range of applicability. Thus, the proposed models may be used for preliminary designs of a chevron PHE.


identifier: Mujahid, Ali <https://research.library.mun.ca/view/creator_az/Mujahid=3AAli=3A=3A.html>   (2021) Comparing climate change messaging and COVID-19 messaging: a case study of the World Health Organization.  Masters thesis, Memorial University of Newfoundland.

abstract:
Climate change is an existential threat to humankind. To communicate the level of the danger as
well as possible solutions to it, decades of research has gone into how to make climate change
communication and messaging more effective, in order to spur people to adapt individual
behaviour and increase support for policy action to counter the threat. This thesis aims to draw
parallels between climate change and the COVID-19 pandemic, arguing that both are wicked
problems for which communication can be similarly addressed through a common lens. It
identifies three widely used messaging strategies from a systematic literature review: scientific
consensus messaging, inoculation messaging, and gain framing. The thesis will conduct a
systematic document review and qualitative analysis of the World Health Organization’s (WHO)
COVID-19 messaging from January 2020 till August 2021, analyzing the extent to which these
three communication strategies or any novel WHO communication strategies are present. It finds
that there is some evidence of usage of both inoculation messaging and gain framing but,
surprisingly, none of scientific consensus messaging. It also discovers that the most used
messaging strategy is a novel WHO messaging strategy, which, for the thesis, is labeled as
Information, Explanation, and Solution (IES). There are also large parts of WHO’s COVID-19
communication that does not seem to deploy any messaging strategy at all but could benefit from
such usage. The thesis shows examples of how current WHO messaging can be improved with all
three messaging strategies and visualizes an integrated approach where the IES strategy is
combined with others from climate change communication to maximize message efficiency. It
goes on to illustrate broader lessons for COVID-19 messaging from climate change messaging
and envisages a two-way street where lessons from COVID-19 messaging may also inform
messaging campaigns for climate change and other comparable institutions.


identifier: Yu, Yajun <https://research.library.mun.ca/view/creator_az/Yu=3AYajun=3A=3A.html>   (2022) Genetic and clinico-demographic factors with and without time-varying associations with survival outcomes in colorectal cancer.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Predicting the risk of outcomes (e.g., death, tumor recurrence/metastasis) as well as when
a patient has such high risks are important, as this information can guide the disease management
and patient care in colorectal cancer. However, current established prognostic markers in
colorectal cancer predicting such risks are not sufficient to stratify patients into appropriate risk
groups, suggesting the need for additional prognostic markers. In addition, there are no
established prognostic markers that can tell whether a patient has high outcome risk in different
time frames following diagnosis. The main aim of this research was to examine the relationship
between genetic/clinico-demographic factors and clinical outcomes in colorectal cancer and to
identify factors that associated with patient outcomes with or without time-varying associations.
To this end, I examined ~4.7 million SNPs and hundreds of CNVs/INDELs for their
associations with outcomes in colorectal cancer. My results showed that a number of
CNVs/INDELs in BRM-741, TGFBR3, FILIP1L, STEAP2, RP11-143P4.2, and a SNP
(rs7314075) in WBP11 are associated with time to outcome events in colorectal cancer. Further,
two CNVs in PDLIM3 and GUSBP1 were identified to be associated with patient outcomes
within the first ~3 years post-diagnosis, but not after that (i.e., candidate early-outcome markers);
another three variants (rs817090, rs11064732, and rs200143895) were found to be associated
with patient outcomes after 5 years post-diagnosis, but not before that (i.e., candidate lateoutcome
markers). I also examined a set of baseline clinico-demographic factors, where a
number of them were identified to be associated with outcomes in colorectal cancer, including
those that have time-varying associations. By investigating a long follow up data, I was also able
to examine the long term survival characteristics in this disease.
This comprehensive research described a detailed picture of genetic and clinicodemographic
factors with and without time-varying associations with clinical outcomes in
colorectal cancer. It provided a set of variants/factors as candidate markers predicting outcome
risks for colorectal cancer patients, including candidate early- or late-outcome markers. These
factors, once their prognostic value is validated, can be used to guide patients’ treatment and
clinical care, and improve their survival times.


identifier: Keogh, Poppy <https://research.library.mun.ca/view/creator_az/Keogh=3APoppy=3A=3A.html>   (2022) The Charlie-Gibbs Fracture Zone: megabenthic biodiversity, community composition and their environmental drivers.  Masters thesis, Memorial University of Newfoundland.

abstract:
The Charlie-Gibbs Fracture Zone (CGFZ) is a topographically unique area on the Mid Atlantic Ridge (MAR) with numerous bathymetric features which create a heterogenous environment, optimal for the colonisation of cold-water sponge and corals. Previous studies have analysed the megabenthic communities North and South of the fracture zone, but not between the two parallel faults themselves. The region which was surveyed for this study is within the CGFZ North Marine Protected Area (MPA), where the benthic habitats currently remain unprotected from anthropogenic activities. This thesis aims to describe the biodiversity patterns and community composition of the CGFZ as well as their environmental drivers. We use video footage from five transects collected using a Remotely Operated Vehicle and multivariate statistical methods. Over 154,509 individual organisms belonging to 309 megafaunal morphospecies were identified from the video which covered almost 34 km of transect. Using species accumulation curves and generalized additive modelling, depth, slope and the presence of hard substratum were determined to be important factors in the distribution of megafaunal species richness and abundance. When the megafaunal community composition was examined, eight distinct communities were identified, all with multiple Vulnerable Marine Ecosystem indicator species present. These included but were not limited to a sea pen field alongside an Acanella sp. garden, and a community dominated by corals including the black coral Stichopathes sp., soft corals like Anthomastus sp., and scleractinians. Depth, slope and rugosity played a significant role in their differentiation and distribution of these communities. These results will help to inform the future decision making for this region,
the CGFZ North MPA, where its protection status will come into debate in the next five years.


identifier: Pevie, Cally <https://research.library.mun.ca/view/creator_az/Pevie=3ACally=3A=3A.html>   (2021) Psychological distress in Canadian males and females reporting childhood sexual abuse: exploring the role of social support.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Childhood sexual abuse (CSA) is a severe form of childhood maltreatment that has consistently been associated with deleterious biopsychosocial outcomes spanning into adulthood. CSA prevalence rates in the Canadian adult population have been estimated at 8% with females demonstrating higher rates (12% - 15.2%) than males (4% - 4.8%; Burczycka, 2015; Pereda et al., 2009). While perceived social support has been identified as a potential protective factor for CSA survivors, further investigation is required to elucidate the types of social support that are beneficial for males and females in this population. Data associated with a sample of 1,328 Canadian adults (20-64-years-old) reporting CSA before the age of 16 were extracted from the 2012 Canadian Community Health Survey of Mental Health (Statistics Canada, 2013a) and analysed. It was observed that the CSA sample had significantly higher levels of distress, and lower levels of social support (overall and for each subscale) than the entire adult Canadian sample, with the male CSA sample reporting significantly lower levels of social support (overall and for each subscale) compared with the CSA female sample. Subsequent hierarchical regressions revealed that social support predicted 18.5% of the variance in psychological distress in the overall CSA sample after controlling for age, personal income, and biological sex, with guidance, reassurance of worth, and social integration significantly predicting lower levels of psychological distress in females reporting CSA, and attachment (presence of close secure relationships) predicting lower distress in males reporting CSA. These findings provide further cross-sectional support for the stress-buffering hypothesis in CSA adults and suggest that individuals with trauma histories may benefit from having their social support systems tailored to the type of trauma they experienced and their biological sex. These results are discussed in terms of their clinical relevance in the psychological treatment of adults with CSA histories.


identifier: Fleming, Kathleen <https://research.library.mun.ca/view/creator_az/Fleming=3AKathleen=3A=3A.html>   (2021) “Taken by the fairies” An examination of contemporary fairy commodification and culture in Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract:
On the Avalon Peninsula of Newfoundland, fairies are no longer feared and avoided
(Reiti, 1991; Narvaez, 1991), but are something people have commodified and are marketing and
selling. This thesis includes some of these examples: Tina White’s guided tours the Fairy Door
Tours and Fairy Lore Walkabout, the Faerie Garden and Fairy Nights at the Cupids Legacy
Centre, described by Claudine Garland and Peter Laracy, and the written representation by local
writers Dennis Flynn and Dale Jarvis, and local publisher Marnie Parsons who owns and
operates the Running the Goat: Books and Broadsides publishing company in Tors Cove.
Applying the theoretical concepts of play (Masters, 2008; Eicher-Catt, 2016; Lambrow, 2020),
assemblage (Santino, 1986), enchantment/re-enchantment (Magliocco, 2018; Saler, 2003, 2004),
and escapism (Heilman, 1975; Young, 1976; Usherwood and Toyne, 2002), to the theoretical
framework of commodification, I show how locals are adapting “our” fairy traditions and using
the interest sparked by the popular culture representation of fairies to teach audiences about
different aspects of Newfoundland culture, such as storytelling traditions, as well as
Newfoundland values, like respect for nature and for other people. I also show how the visual
representation of fairies has been more sanitized than the written form. Finally, I show how
locals, both proprietors and consumers, are using these examples to create and foster a sense of
local identity.


identifier: Archer, J.D. <https://research.library.mun.ca/view/creator_az/Archer=3AJ=2ED=2E=3A=3A.html>   (2021) Smoky, noisy, bloody, violent, and smelly: the seventeenth-century detached kitchen at Ferryland, Newfoundland.  Masters thesis, Memorial University of Newfoundland.

abstract:
This thesis focuses on a 17th-century detached kitchen in Ferryland, Newfoundland, built at the rear of a multi-room service wing and forming part of the complex of structures referred to as Sir George Calvert’s ‘mansion house.’ This structure is referred to in this thesis as the ‘mansion house kitchen.’ Historical documentation provides evidence that the kitchen was built sometime between 1622 and 1628, while clay tobacco pipes and other datable artifacts show that it continued to be used, albeit less intensively, following Sir David Kirke’s arrival in 1638. Architectural remains reveal that the kitchen was a sturdy structure, 8m by 7m, with lime mortared slatestone walls that were approximately 1m thick. It was built directly into the hillside, at a level with the second storey of the mansion house, and with a cobblestone pathway leading between the two. Artifacts excavated from midden deposits directly outside of the kitchen’s walls provide evidence for a variety of activities including food preparation, cooking, sewing, and other domestic tasks.
The kitchen was central to the daily life of the early modern English household (Pennell 2016: 87). Food took up a significant portion of the average household’s budget, while the activities which took place in and around the kitchen—meal preparation, cooking, gardening, cleaning, sewing—took up a considerable amount of the average housewife’s time and energy (Weatherill 1996: 135, 146). Food was also closely connected to a family’s social identity, and the daily rhythm of tasks in the kitchen played a key role in maintaining the household (Weatherill 1996: 149-150). An analysis of Ferryland’s mansion house kitchen has the potential to add to our understanding of how these trends were expressed in early English colonial settlements, where provisioning was of crucial importance and food could take on aspects of
cultural identity. This thesis will make use of the kitchen’s architectural remains and associated material culture to gain insight into the daily lives of its occupants, how it related to the rest of the community, and how its architectural design was influenced by and relates to detached kitchens elsewhere in North America and the UK.


identifier: Critch, Tristian <https://research.library.mun.ca/view/creator_az/Critch=3ATristian=3A=3A.html>   (2022) The Yin and Yang of L-Type calcium channels: age-related roles in learning and memory.  Masters thesis, Memorial University of Newfoundland.

abstract: L-Type calcium channels (LTCCs) are intricately involved in the process of learning and memory. In the young population, the LTCCs are beneficial to the learning process and help facilitate the learning process. As we age, our ability to recall and form new memories deteriorates. We hypothesize that there is a paradoxical shift in the role of LTCCs in learning and memory during ageing. Specifically, there is an increase in the number of or hyperfunction of the LTCCs present in the cell as we age, increasing calcium entering the cell. This causes divergence from calcium homeostasis, thus being a mechanism contributing to a decline in one’s cognitive ability. In this work, we have set out to systematically investigate the potential effects of blocking LTCCs using a calcium channel antagonist, nimodipine, at various ages. Using an odour associative learning task and a spontaneous location recall test, we find that LTCC blockade impairs performance of young rats while rescuing performance of aged rats, demonstrating the shift in their role during ageing. Further, nimodipine infusions into the CA1 region of the hippocampus and the piriform cortex block learning as well as prevent c-Fos activation in the piriform cortex, showing the critical role of LTCCs in synaptic plasticity in young rats. These findings further elucidate our current understanding of the roles that LTCCs play when it comes to memory formation, function, and duration.


identifier: Saha, Shaykat <https://research.library.mun.ca/view/creator_az/Saha=3AShaykat=3A=3A.html>   (2022) Enhancing intensity of tumor-specific fluorescence by MEK inhibition in brain tumor models.  Masters thesis, Memorial University of Newfoundland.

abstract: Fluorescence guided surgery using 5-aminolevulinic acid (5-ALA FGS), a technique widely used to resect brain tumors, relies on fluorescence signals from Protoporphyrin IX (PpIX) accumulated in cancer cells to identify and resect tumor tissue. Despite its clinical success, a major issue of 5-ALA FGS is the insufficient accumulation of PpIX in tumors, posing challenges to the surgeons to delineate tumor ends. Our previous research showed that MEK inhibition increases PpIX accumulation in cancer cells but not in normal cells. In this study, we aimed to screen different MEK inhibitors for their efficacy in promoting 5-ALA mediated PpIX accumulation in human brain cancer cell lines in vitro. Furthermore, we sought to develop an animal model of brain cancer to evaluate the efficacy of screened MEK inhibitors in enhancing tumor visualization in vivo. By conducting in vitro fluorescence measurements, we found that MEK inhibitors Trametinib and Selumetinib were most effective in promoting PpIX accumulation in cancer cell lines. For its consistent robust effect in vitro, Selumetinib was selected for evaluation in in vivo experiments. We successfully developed a mice brain tumor model in Balb/c mice by allografting mammary cancer 4T1 cells into the brain's right hemisphere. Preliminary 2-Photon imaging results show a substantial increase in PpIX fluorescence in mice treated with Selumetinib and 5-ALA compared to mice with vehicle (DMSO/saline) and 5-ALA treatment. These results indicate the potential use of MEK inhibitor treatment to promote PpIX fluorescence in brain tumors for improved 5-ALA FGS in clinical settings.


identifier: Cameron, Ashley <https://research.library.mun.ca/view/creator_az/Cameron=3AAshley=3A=3A.html>   (2022) Archaeological material analysis of FjCa-51, area 11 Sheshatshiu, Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract:
Excavation at archaeological site FjCa-51 in Sheshatshiu, NL has been ongoing
since 2009, at the request of the Sheshatshiu Innu First Nation. FjCa-51 is reported to be
one of the most significant Intermediate period (3500-1800 BP) archaeological sites in
Labrador with fifteen different loci excavated to date. As most of the cultural material of
the Intermediate period is lithics, an analysis following a chaîne opératoire approach was
completed in order to understand site use, movement and/or trade across the land, and
how Area 11 fits into the existing Intermediate period classifications. Residue analysis
was completed on five anvil stones in order to discern whether the analysis would provide
results regarding the processing of organic materials on site. The results suggest that Area
11 was a short-term habitation site that saw only a single occupation that had both local
and non-local stone raw materials suggestive of movement or trade. The artifacts are also
a mixture of diagnostically Charles and Brinex complexes, now considered the Saunders
phase, so Area 11 has been placed into this phase. Results were obtained from the residue
analysis providing evidence for cold season grasses and possible bison processing on site.
All of the above analyses are discussed together in order to fully understand how Area 11
of FjCa-51 was utilized.


identifier: Ahmadkelayeh, Sara <https://research.library.mun.ca/view/creator_az/Ahmadkelayeh=3ASara=3A=3A.html>   (2022) Extraction of lipids and astaxanthin from Northern Atlantic shrimp by-products: “green”/sustainable extraction process, statistical optimization study and mathematical modeling of kinetic extraction.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
The shrimp by-products from shrimp processing are typically disposed of as “waste” into
landfills or the oceans, representing an environmental and economic cost. Shrimp
processing by-products from harvesting and processing are a source of valuable
biomaterials/bioactive materials (such as lipids and astaxanthin) for use in the
pharmaceutical, cosmetic, food industries, and biomaterials. Extraction of these
compounds would reduce the environmental burden and enhance the industry’s finances.
However, in order to determine the feasibility, the quality and quantity of lipids/astaxanthin
in the by-product as a function of extraction conditions and pre-treatment is required. This
information on the quantity/quality of the extract in terms of lipid/FA and astaxanthin
(ASX) compositions is required for product application (nutritional, medical, etc.).
Traditionally, lipids and ASX are extracted using energy/waste intensive processes, which
can degrade the product and/or by-products, are difficult to scale up, and/or operationally
complex. However, the development of “green” valorization processes has made recovery
of bioactive compounds from shrimp processing by-products feasible.
In this study, we outlined (1) literature review on the advances in the field of value-added
lipid/ASX recovery from shrimp and other crustacean processing by-products with a
particular focus on SC-CO₂, (2) a comprehensive analysis of the quality and yield of
lipid/ASX extract as a function of the extractant solvent used (Soxhlet) and pre-treatment
(freeze-drying) of the by-products, (3) the viability of ASX extraction using waste
fish/sunflower oils and optimization of waste fish oil extraction of ASX from wet and
freeze-dried (FD) shrimp by-products as a function of water content and operating
conditions (time, temperature and oil:waste ratio), (4) optimization of SC-CO2 extraction
of lipid/ASX from FD shrimp by-products as a function of temperature/pressure; study of
the impact of static co-solvents adding to SC-CO₂ on lipid/ASX yields, quality and
lipid/fatty acids distributions, and (5) mathematical model to predict lipid/ASX extraction
rates at certain operating conditions of temperature, pressure and flow rate.
According to Soxhlet extraction results, in general, a mixture of polar/non-polar solvents
maximized lipid/ASX yields, and the extract quality can be tuned with a proper solvent
mixture to favour lipid yield, ASX yield, or a balance of both depending on the final
application. ASX yields varied from 57-88 μg/gwaste depending on Soxhlet solvent(s) for
wet shrimp by-product to 118-218 μg/gwaste for the freeze-dried. Lipid extracts are rich in
omega-3 FAs and the composition of lipid classes varied with solvent(s) used and pretreatment.
Overall, pre-treatment to remove water decreased lipid yield but increased ASX
yield/quality.
Edible waste oils are a potentially “green” solvent that could replace organic solvents and
act to prevent degradation of the extracted ASX. This study investigates waste fish oil as a
solvent for ASX extraction from Atlantic shrimp by-products (Pandalus borealis). This
study observed that the higher the water content in the residues, the lower the ASX amount
in the extract. As extended extraction times or high temperatures the ASX yield decreased;
this is due to degradation of ASX with time/temperature. The optimal conditions to
maximize the yield of ASX from both wet and freeze-dried shrimp by-products were 65 ˚C,
9:1 v/w and 1.5 h. ASX extractions were 40-60 % lower compared to Soxhlet, however the
waste fish oil extracts were higher in triacylglycerols and omega-6 FAs.
SC-CO₂ extracted the highest lipid yield at 50 ˚C and 30 MPa, and the highest ASX yield
and total carotenoid content (TCC) at 60 ˚C and 32 MPa. Lipid/ASX recovery increased
with an increase in pressure; however, temperature had a complex impact on lipid/ASX
yield at a constant pressure. SC-CO₂ extract fractions had high percentages of neutral lipids
but low phospholipids. Static co-solvent in SC-CO₂ provided the same lipid yield as and
the higher ASX yield than the published papers using continuous co-solvent/SC-CO2. Polar
co-solvent increased lipid/ASX recovery using SC-CO₂. Sunflower oil recovered higher
ASX compared to waste fish oil. Polar co-solvents increased phospholipids and saturated
fatty acids but decreased monounsaturated FAs and polyunsaturated FAs in the SC-CO₂
extract. Lipid compositions of sunflower oil extract was the same as sunflower oil, but the
extract using waste fish oil in SC-CO₂ had higher sterols and free FAs compared to the
lipid profile of waste fish oil. The highest lipid yield extracted using SC-CO₂ was 0.5 times
of lipids extracted using ethanol in Soxhlet. The highest ASX yield with SC-CO₂ was 0.3
of ASX yield using a mixture of 40:60 vol% hexane/acetone in Soxhlet, and the highest
TCC was 0.4 of the highest TCC obtained using Soxhlet (60:40 vol% hexane/isopropanol).
The SC-CO₂ kinetic data were in good agreement with the mathematical model (Goto et
al. 1993) used for both lipid/ASX extraction rates. The AARD values were 6 % for lipid
extraction and 7.8 % for ASX extraction. Overall extraction rates of lipid/ASX were
controlled by the strong solid–solute interaction.


identifier: Li, Yuting <https://research.library.mun.ca/view/creator_az/Li=3AYuting=3A=3A.html>   (2021) Functional analysis of MbtH-like proteins in the biosynthesis of thaxtomin A in Streptomyces scabiei 87.22.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Streptomyces scabiei is an important causative agent of potato common scab disease. The main pathogenicity factor produced by this organism is thaxtomin A, a phytotoxin that is also a promising bioherbicide for agricultural applications. The biosynthesis of thaxtomin A involves the nonribosomal peptide synthetases (NRPSs) TxtA and TxtB, both of which contain an adenylation (A-) domain that recruits and activates the amino acid substrate to be integrated into the product. A small gene, txtH, encoding a predicted member of the MbtH-like protein (MLP) family, is also present in the thaxtomin (Txt) biosynthetic gene cluster. MLPs are normally required for proper folding of the A-domain(s) and/or for stimulating the enzymatic activity of the domain. In addition, some MLPs can interact with NRPSs from different biosynthetic pathways, though the mechanism behind this is not fully understood.
Here, I investigated the role of MLPs during thaxtomin A biosynthesis in S. scabiei. The results showed that TxtH likely functions as a chaperone protein for ensuring the proper folding of the TxtA and TxtB A-domains, and that this function is essential for thaxtomin biosynthesis in S. scabiei. Using site-directed mutagenesis, I identified amino acid residues within TxtH that are important for the function of the protein. I also showed that two other MLPs encoded in the S. scabiei genome can promote thaxtomin production in the absence of TxtH, indicating that they can exhibit functional cross-talk with TxtH. A survey of various MLPs from diverse phylogenetic lineages revealed that most of these MLPs can exhibit functional cross-talk with TxtH to varying degrees, though two MLPs were identified that could not replace TxtH in the assays performed. In silico analysis revealed that the conservation of key residues at the Txt MLP-NRPS interacting interface
may determine the ability of an MLP to interact with the Txt NRPSs. I additionally attempted to assess the impact of TxtH and other MLPs on the enzymology of the Txt A-domains in vitro; however, my assays were unsuccessful despite testing different conditions. Overall, this study is the first to investigate the function of MLPs during thaxtomin A biosynthesis in S. scabiei.


identifier: Liu, Jingyu <https://research.library.mun.ca/view/creator_az/Liu=3AJingyu=3A=3A.html>   (2021) Characterization of an orphan specialized metabolite biosynthetic gene cluster in the potato common scab pathogen Streptomyces scabiei.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Streptomyces scabiei is the main causative agent of potato common scab (CS) disease, which causes significant economic losses to potato growers worldwide. The ability of S. scabiei to cause CS is primarily based on the production of a phytotoxic specialized metabolite called thaxtomin A, which is an essential virulence factor for the organism. In addition, S. scabiei has the genetic potential to produce other specialized metabolites that might contribute to CS disease development; however, most of the genes predicted to be involved in production of these specialized metabolites are silent under laboratory conditions, and thus there is little known regarding the nature of these metabolites and their role in CS disease. The aim of this research was to characterize one cryptic specialized metabolite that is thought to resemble a phenazine. The putative biosynthetic genes that produce this cryptic metabolite are expressed at low levels or not at all under laboratory conditions, and therefore different strategies were employed to activate or enhance expression of these genes in S. scabiei.
Specifically, the first approach taken was to use different bioinformatics tools to predict the boundaries of the biosynthetic gene cluster (BGC), and it is proposed that the BGC is much larger than initially thought. Molecular and culture-based strategies were successfully employed to activate expression of the BGC, and this also enabled a better understanding of the role of predicted regulatory genes in controlling the expression of the BGC. Metabolomics analysis conducted in this study suggests that the BGC is involved in the production of phenazine-related metabolites. This analysis additionally provided new insights into the overall specialized metabolic potential of S. scabiei and enabled the prediction of several novel compounds that were not previously known to be produced by this organism. The phenazine-like BGC is conserved in the genomes of other Actinobacteria, including two phytopathogenic Streptomyces spp. Although the
role of the resulting metabolite(s) in the pathogenicity of S. scabiei remains unclear, evidence is presented in this thesis suggesting that the molecule(s) may exhibit antibacterial activity, and thus may have a function in inter-microbial interactions as described for other phenazine-producing organisms.


identifier: Brown, Katie <https://research.library.mun.ca/view/creator_az/Brown=3AKatie=3A=3A.html>   (2022) Tip-enhanced Raman spectroscopy: a preliminary study and force spectroscopy of collagen matrices.  Masters thesis, Memorial University of Newfoundland.

abstract:
This thesis contains preliminary work on tip-enhanced Raman spectroscopy (TERS).
TERS is a spectroscopy technique that uses AFM and Surface-enhanced Raman spectroscopy
(SERS) to achieve nanoscale images accompanied by chemical maps. TERS
can be used to identify compounds that cannot be detected with conventional Raman,
such as those masked by fluorescence. Raman of retinal tissues, specifically, Raman
of vitamin A (retinol) within the tissues, has been of interest within the Merschrod
group, and steps have been taken within this thesis to work toward this goal. Computational
Raman spectra of vitamin A and its derivatives have been completed to
assist in identifying these compounds within the tissues. Biological tissues have many
different components that can be detected, and vitamin A has many different products
as it is degraded by light and air. These spectra can help distinguish peaks of
these compounds, making analysis easier.
The second part of the thesis covers force spectroscopy of collagen. Collagen is
one of the main components of cell culture matrices. Previous studies indicate that
changing the collagen overlay within the matrices can affect cell behaviour. The
mechanical properties of these overlays may cause a change in the behaviour. It is
also known that biological tissues have a change in mechanical properties when probed
at different length scales. Using atomic force microscopy (AFM), I investigate the
effect of tip radius on Young’s modulus (stiffness) of three different collagen matrices:
fibrils, PBS collagen and HANKS collagen. The indentation studies indicate that
increasing the radius of the indenter decreases the measured Young’s modulus of the
sample. This suggests that the fibrils in the matrices are stiffer while the network
of the matrices is softer and allows more stretching. These results tell us about the
multi-scale properties of tissues.


identifier: Duffett, Colin Arthur <https://research.library.mun.ca/view/creator_az/Duffett=3AColin_Arthur=3A=3A.html>   (2020) Effect of slow velocity isokinetic knee actions on slow and fast velocity contralateral knee action performance.  Masters thesis, Memorial University of Newfoundland.

abstract:
Fatigue is a complex, multifactorial phenomenon that affects the neuromuscular system from the muscle fibers and neuromuscular junction to the higher planning centers in the brain and reflects interactions along the entire system. ‘Neuromuscular fatigue’ refers to the decrease in physical performance associated with an increase in the real and/or perceived difficulty of a task, regardless if the force or power can be sustained, and is present and progressing from the onset of the task that is reversible with rest. It consists of central and peripheral components such as decreases in central drive (central fatigue) or contractile responses (peripheral fatigue) and is suggested to occur at any site involved in the muscle contraction. Fatigue also has a mental component that describes an emotion suggested to act as a warning sign for maintaining physical integrity. Neuromuscular fatigue may depend on both the muscles employed and on the type of exercise from which fatigue results and are specific to the task and dependent on the mechanisms which are the most stressed during the task.
Fatigue can either be localized or global, meaning it can affect the muscles exercised or the entire body system resulting in fatigue effects in non-exercised muscle groups. A growing body of research revolves around the effects of fatiguing exercise and their impact on the performance of non-exercised muscles, termed non-local muscle fatigue (NLMF). The presence of NLMF effects is conflicting, with effects seemingly dependent on many factors such as contraction intensity, fatiguing exercise volume, muscle group fatigued and tested, muscle action, and the detection method(s) used. NLMF research has many implications for rehabilitation and training purposes, as well as widening our understanding of global fatigue mechanisms. A relatively unexplored aspect of NLMF is whether the testing is velocity specific. The purpose of this study was to investigate the effects of fatigue induced by simultaneous low velocity unilateral isokinetic knee extensions and flexions on contralateral knee slow and fast velocity extensor and flexor isokinetic force and electromyography (EMG). In a randomized, repeated measures, crossover design, peak torque, EMG, and rate of perceived exertion measures were measured from the non-dominant vastus lateralis and biceps femoris before and after unilateral fatiguing protocols of the dominant knee extensors and flexors. The fatiguing protocols consisted of 4 sets of 15 maximal isokinetic knee extension and flexion contractions. In addition, a fatigue resistance test was also completed post-intervention.
The current study used 16, university-aged (ages 18-30) participants (10 males and 6 females) who were resistance trained. Peak torque of the dominant (exercised) quadriceps and hamstrings decreased when tested at slow and high velocities. Peak torque of the non-dominant quadriceps and hamstrings during post-test (p=0.6 and p=0.3 respectively), or first or last repetition of repetitive fatigue test (p=0.8, p=0.06, and p=0.8, p=1.0, respectively) tested at slow velocity was not significantly different from control, demonstrating a lack of peak torque or fatigue endurance NLMF effects. In addition, there was no relative (normalized) differences in peak torque for velocity specific or fast test velocities. However, the fast velocity repetitive fatigue test resulted in a greater decrease from first to the last repetition than the slow test, as demonstrated by the fatigue index (FI), but was not significantly different from control. This study highlights that prior unilateral fatigue of the dominant quadriceps and hamstrings by repetitive slow maximal isokinetic actions did not demonstrate decreases in singular maximal peak torque or repetitive fatigue endurance in the contralateral muscles. In addition, velocity specific effects were not demonstrated in relative peak torque or relative fatigue endurance changes. There was also no observable effect on the rating of perceived exertion following control vs fatigue (4.6 vs 6.3, p>0.05), or slow vs. fast testing (5.8 vs 6.8, p>0.05) on post-repetitive test values.


identifier: Deklu, Gladstone <https://research.library.mun.ca/view/creator_az/Deklu=3AGladstone=3A=3A.html>   (2021) Ewe vowel harmony: implications for theories of underspecification.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
This thesis examines vowel harmony in Ewe, with a focus on the northern dialect. I show that harmony patterns seen in the northern dialect differ from what has been proposed as a general analysis for the language by Clements (1974). The patterns seen in the northern dialect highlight asymmetries in the behaviour of the vowels /a/ and /ɛ/. These vowels are triggers of harmony in some contexts (i.e., Low harmony), whereas in others, they are targets of harmony (i.e., Height harmony for /ɛ/ and Place harmony for /a/). I argue that this asymmetry can be explained by considering the phonological representation of these vowels as well as relying on the mechanisms of lexical phonology and morphology. I then situate my analysis within Stratal Optimality Theory.
Regarding the phonological representation of vowels, I follow Reiss (2017) and propose that contrast is not relevant in the representation of vowels in Ewe; these vowels must be specified for features based on phonological activity. Given this, their specifications reflect what phonological processes each vowel triggers in the language. I provide further evidence supporting this analysis by highlighting the failures of theories of representation that rely on contrast in the face of Ewe data. As part of this discussion, I explore both Radical and Contrastive (under-)specification as well as the Contrastive Hierarchy.
I propose that Height and Place harmony are lexical processes, and that Low harmony is a post-lexical process. This proposal is based on the characteristics displayed by these processes, which I also consider in light of cross-linguistic evidence.
Within Stratal OT, I assume a strong version of Richness of the Base and argue that underlying representations cannot be restricted by the grammar. Thus, any combination of features is allowed in the underlying representation. Through the interactions of violable constraints, I derive vowel feature specifications based on activity at the stem level of derivation. I observe that constraints that are antagonistic to phonetic richness are ranked higher at this level of derivation, while those favouring it are ranked lowly. The output of the stem level then feeds the word level of derivation, where the lexical processes take place. At this level, the grammar preserves features through a high ranking of faithfulness constraints. Thus, segments are not further impoverished at this level of derivation. At the phrasal level, where Low harmony applies, different constraint rankings capture the observation that /a/ and /ɛ/ are not targets of harmony, and that /ɛ/ is a trigger of harmony.


identifier: Kippenhuck, Garreth <https://research.library.mun.ca/view/creator_az/Kippenhuck=3AGarreth=3A=3A.html>   (2022) Understanding corticospinal excitability to the biceps brachii during maximal repeated arm-cycling sprints.  Masters thesis, Memorial University of Newfoundland.

abstract: Studies investigating neuromuscular fatigue (NMF) induced by repeated sprint exercise primarily use a tonic contraction to assess corticospinal excitability (CSE). There is a lack of information about how CSE transiently changes with rapidly changing fatigue levels. Previous research has shown that CSE is dependent on a variety of factors, such as the targeted muscle, mode of exercise, hand position, cadence, cycling direction, and level of fatigue. No study has assessed CSE during repeated maximal arm-cycling sprints. The current study circumvents the limitations of a tonic contraction to assess CSE. We performed maximal repeated arm-cycling sprints using a custom-built cycle ergometer. Transcranial magnetic stimulation (TMS), transmastoid electrical stimulation (TMES), and brachial plexus stimulation (Erb’s point) were given during each sprint to determine how CSE to the biceps brachii was modulated during 5, approximately 20 second repeated sprints. The sprint protocol induced NMF as evidenced by mean power (p < 0.0001) and total work (p < 0.0001) dropping by 36.8% from sprint one to five respectively. There was a 4.57% decrease in TMES intensity required for the active motor threshold (AMT) from pre- (134.00 ± 31.52 mA) to post sprinting (124.17 ± 30.08 mA), t (12) = 3.445, p = 0.0055. Our findings suggest that our protocol increased spinal and peripheral excitability from pre to post sprinting, but not cortical because of the absence in change in MEP amplitudes from pre to post sprinting Changes at the spinal motoneuron and post-activation potentiation are likely mechanisms associated with the modulations.


identifier: Miatta, Marta <https://research.library.mun.ca/view/creator_az/Miatta=3AMarta=3A=3A.html>   (2022) Biodiversity and ecosystem functioning in contrasting marine habitats: patterns, drivers, and implications for conservation planning.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
The patterns and drivers of marine biodiversity and ecosystem functioning and how biological communities influence ecological processes remain poorly understood, especially for deep-sea and other remote environments. Such constraints impair effective protection of important organisms and ecosystem functions from human impacts and global change through conservation strategies such as Marine Protected Areas (MPAs). This thesis explores different aspects of biodiversity and ecosystem functioning in deep-sea sedimentary habitats, focusing on macrofaunal biodiversity and organic matter remineralization, which can be quantified through measurement of inorganic nutrient flux rates at the sediment-water interface. I examine the roles of biogenic (e.g., sea pen fields) and geophysical (e.g., submarine canyons) habitats along the Northwest Atlantic continental margin in regulating biodiversity and functioning. Through literature review and experimentation, I explore how biological traits of organisms influence the ecology and functioning of biological communities and can potentially inform MPA design and improve conservation outcomes. My findings demonstrate the important role of biogenic and geophysical habitats in shaping macrofaunal communities, mostly by altering food availability and creating habitat heterogeneity, and the central role of food availability in driving macrofaunal diversity at regional scales. The interacting effects of several abiotic and biotic factors that act over different spatial and temporal scales complicated efforts to discern patterns of organic matter remineralization. Some macrofaunal taxa and measures of biodiversity clearly influenced variation in benthic flux rates, reiterating the importance of biological communities in driving ecosystem processes. Biological trait expression analysis helped in understanding patterns and underlying drivers of community structure, despite poor correlations between traits and benthic flux rates, highlighting the need for further studies. The findings of this study highlight the importance of
protecting multiple ecologically important and sensitive marine habitats in order to maintain biodiversity and functions, but also punctuate the need for further studies to characterize biological traits of under-studied organisms and effectively apply trait-based approaches to improve conservation outcomes.


identifier: Ostiguy, Josiane <https://research.library.mun.ca/view/creator_az/Ostiguy=3AJosiane=3A=3A.html>   (2022) Ambient noise levels off the coast of Northern Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract:
Ambient sound data was recorded over a 6 month period from October 2017 to March 2018 and a 15 month
period from July 2019 to September 2020. This data was recorded from a mooring at the northeastern
edge of Saglek Bank off Northern Labrador, where the water depth is 500 meters. High biodiversity and
limited shipping activity make this an area of interest. At the mooring location, tidally driven currents are
driven to speeds of up to 50 cm/s. The high current speeds result in a significant tilting of the mooring,
with the instrument often indicating tilts in excess of 20 degrees. Further, the high speeds lead to mooring
noise which corrupts the ambient sound data. We use current meter data to identify periods of reduced
current speeds where sound data is not corrupted, thereby recovering a record of naturally occurring sounds.
Tidal predictions are used to sort the acoustic data for periods where current speeds are unavailable. The
reduced data set is used to explore noise levels in this area and obtain surface wind speed and rainfall rate
estimates. A bottom interaction model is described and evaluated to asses the impact of bottom re
ections
on noise levels and to determine the effect on weather estimates. Within the quiet periods of the sound
recordings, whale calls are heard. This thesis also reports on an application of the Phase and Amplitude
Gradient Estimation (PAGE) method in an oceanographic context to estimate acoustic intensity. The PAGE
method employs phase unwrapping such that the vector intensity is estimated past the Nyquist limit, and
the direction of the acoustic source is determined with increased accuracy.


identifier: Oyogbuda, Japhet Chikanka <https://research.library.mun.ca/view/creator_az/Oyogbuda=3AJaphet_Chikanka=3A=3A.html>   (2022) Design and simulation of a DC microgrid system for a remote community in Nigeria.  Masters thesis, Memorial University of Newfoundland.

abstract: The thesis presents the design and modelling of an off-grid Stand-alone Photovoltaic (PV) system for a house and DC microgrid system for a remote community. Using a 48V DC bus, the system was sized using Homer Pro and dynamic simulation was done in Simulink. Optimization results presented various designs out of which the most preferred cost effective and efficient system for the house and remote community was selected. The selected remote community is isolated and located far away from the city with no access to the electricity grid. The community is made up of 9 residences which are not more than 100m apart. House 1 was selected as the standard house with a load of 1kWh/day, while the other 8 houses have a load difference of ±10% with reference to house 1. Using a 48V DC bus, the PV systems were designed for each house in the community. The systems were sized using Homer Pro. Optimization results presented various cost effective design for each community house. Sensitivity analysis was carried out to show the robustness for both the single residence and the community microgrid design. Simulation results showing the stability of the system and power sharing in the community using a 48V DC bus. Microgrid dynamic simulation is done in Simulink. Complete details of system design and dynamic simulation results are presented and explained in this thesis.


identifier: Pearson, Shannon C. <https://research.library.mun.ca/view/creator_az/Pearson=3AShannon_C=2E=3A=3A.html>   (2022) The Haunted House is home to horror: an exploratory study of the Haunted House manifest in North American film from 1940–2020.  Masters thesis, Memorial University of Newfoundland.

abstract: Hockey (1999) introduces the House of Doom; Bailey (1999) builds the Haunted House formula from American popular fiction; Meehan (2020) tracks the Haunted House on film and through history; and now, I explore how the Haunted House narrative belies societal concerns about the existential nature of humanity. When COVID-19 forced our global society into at-home isolation, inhabitants were forced to reckon with the effects of prolonged domestic survival, much like the inhabitants of haunted houses. This exploratory ethnographic content analysis of 40 films contributes a trio of phenomenological findings to existing Haunted House scholarship: 1) threats to the safety of one’s home can turn the house into a dangerous trap, 2) as a reification of biophobia, the North American Haunted House is more closely aligned with nature than with civilization, 3) the Haunted Heroines of the horror genre showcase the strength and adaptability of the feminine trope. Oppressors mobilize structural restraints—literally and systemically—to objectify the Female Gothic as a Gothic Corpse, all while personifying inanimate structures. The Haunted House manifests in the North American cultural imagination as a monstrous embodiment of biophobia, a fear of nature and the Self. What happens when you open the door to supernatural metaphors for fears about domestic life and the nature of humanity?


identifier: Sindhu, Muhammad Umair Javed Ilam <https://research.library.mun.ca/view/creator_az/Sindhu=3AMuhammad_Umair_Javed_Ilam=3A=3A.html>   (2022) Temporal Data Placement.  Masters thesis, Memorial University of Newfoundland.

title: Temporal Data Placement

abstract:
How can we provide data where it is required and when it is required to the
execution units of parallel hardware? Program transformations have been a focus
to improve the performance of parallel computing, whereas data optimizations like
data placement, data layout transformation, data migration and data replications are
overlooked especially in compiler domain. We are proposing a methodology, Temporal
Data Placement, that will schedule and place data in both time and space. The use of
our methodology will enhance the performance of parallel systems significantly, and
it can also be automated.


identifier: Gallant, Stephanie M. V. <https://research.library.mun.ca/view/creator_az/Gallant=3AStephanie_M=2E_V=2E=3A=3A.html>   (2021) Use of nanoscale magnetic ferrites as components of plasmonic sensors for SERS detection of persistent organic pollutants.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
This thesis studies the use of magnetic nanoparticles (NPs) as key-components of a
new class of surface-enhanced Raman spectroscopy (SERS) sensors, with the overall
goal being the development of sensors for environmental polyaromatic hydrocarbon
(PAH) monitoring. As SERS relies on electromagnetic field enhancement, magnetic
NPs are a core class of materials which are currently under-utilized in this field,
with the vast majority of reports only using them as a moveable handle. As their
contribution to SERS enhancement has been thus-far negated, this work aims to
study them as the main plasmonic contributor of the surface.
A patterned magnetic surface was developed using an external field to create a
heirarchical multilayer, where one version uses classic iron oxide NPs (IONPs), and
another uses cobalt ferrite NPs (CFNPs). The patterned IONP surface has signal-tonoise
ratios of 3 dB, exhibiting excellent signal and also longevity, as IONPs are capped
with an inert layer. Analogous CFNPs are synthesized to understand how differing
magnetic properties and geometries could change sensor performance. CFNPs are
synthesized at different reaction scales, resulting in variation of magnetic parameters
and particle geometries, which is correlated with differing performance of the surface
once integrated into a sensor. The highest-performing CFNP sensor has signal-tonoise
ratios (SNRs) of 4.5 dB, and additionally, the substrates are reusable.
As these first versions of magnetic NP surfaces prove very useful in plasmonic
applications, this work paves the way to further explore use of magnetic materials for
sensing.


identifier: Nolan, Robert M. <https://research.library.mun.ca/view/creator_az/Nolan=3ARobert_M=2E=3A=3A.html>   (2022) Local identities, discourses, and institutional change: an examination of voluntary municipal amalgamation in Newfoundland and Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract:
This thesis examines the phenomenon of voluntary municipal amalgamation by observing four
cases in the Canadian province of Newfoundland and Labrador. This project draws on insights
from scholarship in historical and discursive institutionalisms as well as rhetoric and identity
discourses to explore the question of why communities voluntarily amalgamate. The comparative
case study observes four cases of amalgamation debate in rural communities of Newfoundland and
Labrador: three cases (Fogo Island, Roddickton-Bide Arm, and Trinity Bay North) in which
amalgamation occurred; and one case (Labrador City and Wabush) in which the communities
considered and decided against amalgamation. The results support the hypotheses that 1)
amalgamation is chosen voluntarily when community members believe they are facing urgent
challenges that are insurmountable as a single community and 2) resistance to amalgamation is
identity-driven, and may be overcome by discourses related to regional identity and community
survival. Using the independent variables of regional identity discourses and concern for
community survival, a framework is proposed to assist policymakers and local government
scholars when assessing the likelihood of voluntary amalgamation.


identifier: Souza de Brito, Bruna <https://research.library.mun.ca/view/creator_az/Souza_de_Brito=3ABruna=3A=3A.html>   (2022) 'I just felt like I was ready to move': tourism sustainability and migration among youth and young families in the Bonne Bay area.  Masters thesis, Memorial University of Newfoundland.

abstract: Periods of economic decline can generate social and environmental problems and disrupt the sustainability of local communities. In response, governments and industries increasingly promote tourism as a tool for development and economic diversification. Tourism development promises to create employment and alleviate problems generated by downturns, such as youth outmigration and population decline. In this project, I use semi-structured interviews and content analysis of policy documents to identify discourses about the role of the tourism industry in helping rural communities to achieve their sustainability goals. I then examine how youth and members of young families experience tourism development in Bonne Bay (Newfoundland and Labrador) and how these experiences shape their migration intentions. The results show that the provincial government emphasizes quantitative measures of growth rather than equity as a framework for interpreting tourism development. However, this contradicts local needs and experiences of how youth and members of young families relate to the tourism industry. The gap between official tourism development discourse and local experiences has important implications for the potential of tourism to contribute to the long-term sustainability of communities in Bonne Bay.


identifier: Vieira dos Santos, Barbara <https://research.library.mun.ca/view/creator_az/Vieira_dos_Santos=3ABarbara=3A=3A.html>   (2022) Amefricanizing social media: black women intellectuals in Brazil.  Masters thesis, Memorial University of Newfoundland.

abstract: The purpose of this research is to look critically at, and demonstrate how, the use of social media by Black women intellectuals in Brazil can be seen as an enactment of Amefricanity, a concept coined by the Brazilian scholar Lélia Gonzalez (1935–1994). Amefricanity values experiences of Black people and their search to decenter colonial power structures in the Americas. This thesis helps to fill the gap regarding the study of social media in relation to decolonial feminisms by considering the relationship between Black women intellectuals in Brazil, social media, and Amefricanity. This work analyzes the Instagram profiles of Juliana Borges and Joice Berth, two intellectuals who often discuss topics related to Black women and the Black population in Brazil. I conducted a qualitative content analysis of their Instagram posts from March 2018 to October 2019. I argue that their posts constitute a form of meaningful knowledge production and dissemination that (a) does not rely on the approval and acceptance of formal scholarly institutions, and (b) enacts decolonial feminist practices through emphasizing their narratives by making their achievements, struggles, and knowledge accessible. The growing presence of Black women intellectuals in digital platforms has become fundamental to feminisms in Brazil.


identifier: Bass, Laura <https://research.library.mun.ca/view/creator_az/Bass=3ALaura=3A=3A.html>   (2022) Through the eyes of She: exploring womens' stewardship and connection to nature using mindfulness and photo elicitation in Newfoundland and Labrador Parks and Protected areas.  Masters thesis, Memorial University of Newfoundland.

abstract: Urbanization contributes to a collective disconnection from nature and an increase in mental health-related illnesses. Women were chosen as the focus for this research, as they suffer disproportionately from anxiety, depression, phobias, and experience comorbidity of conditions. It is well established that spending time in nature is beneficial for an individual’s overall well-being. This study aimed to determine the mental health benefits of practicing mindfulness in nature, and the influence of mindfulness on stewardship for women in Newfoundland and Labrador Parks and Protected areas. This qualitative research used a framework of feminist narrative inquiry to explore ten women’s stories from parks and nature-based experiences using their photographs. Drawing on the influences of Attention Restoration Theory, shinrin-yoku, and mindfulness, this research used photo elicitation and semi-structured interviews to explore natural features that provoked feelings of mindfulness. Gender issues influence women’s experiences in the outdoors. Barriers and facilitators to participation were explored through the sharing of lived experiences. Feelings of fear, the ethic of care, and financial and time constraints were prominent barriers, while participation was facilitated by relationships and community, empowerment, and green exercise. Practicing mindfulness in natural spaces influenced feelings of deeper connection and environmental stewardship.


identifier: Aryal, Sunisha <https://research.library.mun.ca/view/creator_az/Aryal=3ASunisha=3A=3A.html>   (2022) Neuroprotective effects of wild blueberries and sea cucumber extracts.  Masters thesis, Memorial University of Newfoundland.

abstract: Neurodegenerative diseases involve gradual loss of functional neurons leading to cell death. In Parkinson's disease (PD) for instance, there is a loss of dopaminergic neurons, with corresponding bradykinesia, tremor at rest, and rigidity. Idiopathic factors such as increased oxidative stress, glial activation, and mitochondrial changes also contribute to PD. Polyphenols present in wild blueberries and saponins in sea cucumbers have been reported to exert neuroprotective effects. To explore the neuroprotective effects of blueberries in C57BL/6 mice, the lipophilic neurotoxin MPTP was administered subcutaneously, and behavioural tests and relevant protein measurements were carried out. Compared to MPTP-treated mice given a normal diet, MPTP-treated mice given a 5% blueberry enriched diet showed higher tyrosine hydroxylase levels in the midbrain and cortex. Furthermore, there were no differences in behaviour across treatment as measured in the rotarod, open field, or light/dark box. Likewise, to study neuroprotective effects of sea cucumber and aqueous blueberry studies were conducted in cell cultures. Substantia nigra (SN), rat neocortical (RNC), and C57BL/6 mixed cultures were treated with/without 100 μM glutamate or 100 ng/mL alpha-synuclein for 24 hours with/without the extracts. The sea cucumber extracts with glutamate exposure showed higher cell counts in SN and RNC cells; the sea cucumber + aqueous blueberry showed higher cell counts in RNC and mixed culture. Overall, wild blueberries, as well as sea cucumber extracts, possess neuroprotective properties.


identifier: Sneep, Aaron <https://research.library.mun.ca/view/creator_az/Sneep=3AAaron=3A=3A.html>   (2022) Mapping eelgrass and assessing anthropogenic stressors in Placentia Bay and Trinity Bay, Newfoundland and Labrador.  Masters thesis, Memorial University of Newfoundland.

abstract: Seagrasses are declining globally at an accelerating rate. A lack of information on seagrass condition and spatial extent is hindering seagrass monitoring, conservation, and management. This study provides a baseline of eelgrass’ (Zostera marina) extent at several sites in Placentia Bay and Trinity Bay, Newfoundland and Labrador, Canada, providing a reference point for future eelgrass monitoring. Eelgrass was mapped using high-resolution UAV imagery and underwater video. The presence of physical disturbance and eutrophication was assessed using visual analysis of both imagery sources. Additionally, changes in eelgrass landscape structure were assessed in areas with and without the invasive European green crab (Carcinus maenas). The total area of eelgrass mapped was approximately 1km2 across seven sites in Placentia Bay and three sites in Trinity Bay. There were few indications of physical disturbance and eutrophication across the study sites. The site with the largest change in eelgrass (a loss of 98.9% of eelgrass area between 2014 and 2020) in Placentia Bay also had the greatest abundance of beach-washed European green crab carapaces. Observations agree with previous research that has shown that eelgrass in Placentia Bay is predominantly threatened by the invasive European green crab.


identifier: Jeyamanoharan, Dominic <https://research.library.mun.ca/view/creator_az/Jeyamanoharan=3ADominic=3A=3A.html>   (2022) Performance of Class-E inverters under non-resistive loads.  Masters thesis, Memorial University of Newfoundland.

abstract:
Class-E inverters are popularly used in high frequency wireless power transmission because of their compact design and high efficiency. The inverter consists of resonant elements and a transistor, typically a wide band gap device that is toggled to provide an alternating current signal to the load. Although being a highly efficient and flexible converter, most analysis for this inverter assumes resistive loading. In the presence of non-resistive loading, the performance of the inverter can be negatively impacted.
This work investigates the performance of the load-independent Class-E and Class-E push-pull inverters under non-resistive loads. Several solutions are proposed to mitigate or prevent the associated performance degradations. Although the proposed solutions are flexible at working with any applications, the target application for this work is a capacitive coupled wireless power transfer system. It is shown that a suitable matching network or reactive power compensation can maintain highly efficient Class-E inverter performance even under non-ideal loading conditions.


identifier: Manor, Matthew John <https://research.library.mun.ca/view/creator_az/Manor=3AMatthew_John=3A=3A.html>   (2022) Petrology, Hf-Nd isotope geochemistry, and U-Pb geochronology of volcanogenic massive sulfide (VMS)-related felsic rocks and crustal evolution of the Northern Canadian Cordillera, Yukon.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
The Yukon-Tanana terrane in the Finlayson Lake district, Yukon, represents one of the first
arc–back-arc systems that formed adjacent to the western Laurentian continental margin in the mid-
Paleozoic. Back-arc rocks contain many large-tonnage and high-grade volcanogenic massive sulfide
(VMS) deposits, including the felsic-hosted Kudz Ze Kayah, GP4F, and Wolverine deposits. This
study integrates field mapping with petrology, U-Pb zircon geochronology, and whole-rock and zircon
geochemistry and tracer isotopes to establish precise controls on tectono-magmatic activity for the Late
Devonian to Early Mississippian Laurentian continental margin and create new criteria to evaluate the
role of magmatism in regional VMS genesis and its importance in mineral exploration. High-precision
chemical abrasion (CA)-ID-TIMS U-Pb zircon geochronology defines coeval arc (ca. 363.1 to 348 Ma)
and back-arc (ca. 363.3 to 355.0 Ma) magmatism in the Finlayson Lake district that intruded continental
crust of Laurentian affinity. Rapid depositional processes in the basins hosting VMS deposits (e.g.,
Kudz Ze Kayah formation and Wolverine Lake group) are interpreted to have had an important role in
developing highly porous and permeable, water saturated lithofacies that provided optimal conditions
for enhanced zone refining processes and subsequent preservation of massive sulfide mineralization,
which are key features required for the development of high grade and large-tonnage VMS deposits.
Geochemical and isotopic analysis of rocks in a refined chronostratigraphic framework indicates that
VMS-proximal rocks have distinctly elevated high field strength element (HFSE), rare earth element
(REE), Th, and Hf-Nd isotopic excursions relative to VMS-distal back-arc rocks and coeval arc
assemblages. Further, zircon geochemistry indicates that VMS-proximal magmas were hotter, less
fractionated, and contained greater contributions of mantle-derived (i.e., asthenospheric) juvenile
melts compared to VMS-distal magmas. These results indicate that high-temperature back-arc felsic
magmatism occurred at specific time periods coinciding with VMS deposit formation and supports
previous genetic models for VMS mineralization that suggest elevated heat flow and hydrothermal
circulation were due to regional-scale rift-related magmatism (i.e., basaltic underplating) rather than
from local subvolcanic intrusions. This study underscores the importance of integrating mineral-scale
petrology, geochemistry, and geochronology with traditional whole-rock methods to define the primary
tectono-magmatic environments that generated VMS-related felsic rocks on the Laurentian continental
margin, of which can be applied to VMS exploration in other orogenic belts globally.


identifier: Li, Xixi <https://research.library.mun.ca/view/creator_az/Li=3AXixi=3A=3A.html>   (2022) Development of functional improved and environmentally friendly synthetic musks with reduced human health risks using in silico methods.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract: Synthetic musks (SMs) as alternatives to natural musk have been widely used in personal care products (PCPs), such as fragrances, shampoos, soaps, and household items. These SMs are used in increasingly large quantities and are widely detected in natural waters, soil, air, as well as sludge and effluent from the wastewater treatment plants worldwide, including the Arctic region. Some SMs like galaxolide (HHCB) have been recognized as emerging contaminants with potential human health concerns due to their ubiquitous existence, high lipophilicity, and long persistence in the environment. However, the studies on environmental properties, transformation processes, and toxicity of SMs are still very limited, and there is a strong desire for the design of functional approved and environmentally friendly SMs. This study thus focuses on the investigation and evaluation of the environmental and functional properties of SMs, their transformation and toxicity, as well as the design of new SM derivatives based on molecular modelling. It includes the following objectives: 1) conducting a comprehensive literature review to summarize SM classification, synthetic routes, analysis and occurrence, fate and toxicity in the environment, as well as the associated risk and toxicity assessment and pollution mitigation; and 2) evaluating the toxicity of SMs and their transformation by-products; and 3) designing functionally improved and environmentally friendly HHCB derivatives; and 4) evaluating and controlling spontaneous abortion risk in pregnant women caused by inhalation and ingestion of SMs; and 5) assessing the human health risks of SMs from dermal exposure, investigating the bioaccumulation mechanism of SMs on humans and developing the risk control strategies. The study would lead to a better understanding of SM environmental behaviors and health risks and provide the theoretical basis for designing functionally improved and environmentally friendly alternatives of other PCPs.


identifier: Joyce, Mitchell <https://research.library.mun.ca/view/creator_az/Joyce=3AMitchell=3A=3A.html>   (2022) Global hidden champions: key success factors and challenges in the pandemic era.  Masters thesis, Memorial University of Newfoundland.

abstract: This study looks at hidden champions, the unknown market leaders in the business world that capture unimaginable levels of market share, and how they found success during the during the COVID-19 pandemic. This study will approach hidden champions from a new angle, as it will look at case examples and their key success factors from a global, and more specifically, Canadian, standpoint. The effectiveness of several pandemic-era key success factors for hidden champions will be highlighted with the aim of disseminating a set of generalizable recommendations. The key success factors will be discussed using dynamic capability theory, specifically its three stages of sensing, seizing, and reconfiguring, and they are applied to international capabilities, innovative capabilities, and business pivoting capabilities. The data collection for this project was conducted using interviews and targets homegrown hidden champions in Newfoundland and Labrador with humble beginnings and evolved into industry dominating hidden champions. These hidden champions, MYSA and Verafin, validate the key success factors with the aim of disseminating to other SMEs with humble beginnings, the target demographic. The significance of COVID-19 on hidden champions and other SMEs is the primary focus for this study, with a specific focus on the change in industry landscape, business models, market focuses, and how hidden champions succeeded despite the pandemic’s challenges. The businesses that have survived and prospered have been the ones that were the most flexible, the ones willing and capable of innovating and adapting aspects of their business to better succeed, while many of those that did not practice these strategies, unfortunately, were not so successful.


identifier: Biswas, Sourav <https://research.library.mun.ca/view/creator_az/Biswas=3ASourav=3A=3A.html>   (2022) Contractive annulation — a strategy for the synthesis of small, strained cyclophanes.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
Since the inception of cyclophane chemistry, chemists have been fascinated by the pursuit of ever-smaller and more strained cyclophanes owing to the unusual chemical and physical properties that arise in such systems. The strained nature of these systems poses synthetic challenges and the level of challenge escalates with the level of strain in the cyclophanes. As the degree of strain increases, so does the synthetic challenge and a variety of inventive synthetic approaches to small, strained cyclophanes have been developed.
Chapter 1 introduces some important underlying concepts in the area of cyclophane chemistry. A brief summary of different general strategies for the synthesis of cyclophanes is presented. Overall, Chapter 1 serves as a prelude to the subsequent Chapters.
Chapter 2 focuses on the development of a new three-stage strategy (contractive annulation) for the synthesis of highly strained cyclophanes that would be very difficult or impossible to access using existing synthetic approaches. The viability of the contractive annulation strategy has been demonstrated by a nine-step synthesis of a strained [2.1]cyclophane from commercially available [2.2]paracyclophane. X-ray crystallographic analysis of the [2.1]cyclophane pointed toward a strained cyclophane framework. The strained nature of the cyclophane was further corroborated by theoretical calculations.
Chapter 3 describes the results of the two-directional application of the contractive annulation strategy on [2.2]paracyclophane. As revealed by X-ray crystallographic analysis, the product of the two-directional contractive annulation, a [1.1]cyclophane, was found to have a short interplanar distance. The [1.1]cyclophane is the hitherto smallest member of the [m.n]naphthalenophane family. As expected, DFT calculations indicated that the [1.1]cyclophane
is more strained than the [2.1]cyclophane reported in Chapter 2. The emission behavior of the [1.1]cyclophane was tentatively ascribed to an intramolecular excimer formation mechanism.
Chapter 4 describes studies on the synthesis and physical properties of [2.2]paracyclophane/9-alkylfluorene hybrids, wherein a solvent-assisted rearrangement reaction of a [2.2]paracyclophane moiety bearing cyclopentadienone was discovered. The rearrangement could be avoided by generating the cyclopentadienone under mild conditions and using benzynes as dienophiles to afford the targeted cyclophanes. One of the [2.2]paracyclophane/9-alkylfluorene hybrids (containing a triphenylene moiety) was found to exhibit dual fluorescence emission.
Chapter 5 highlights the synthetic utility of two of the intermediates featured in the synthesis of the [2.1]cyclophane in Chapter 2. One of the intermediates was transformed into [2.2]paracyclophane/quinoxaline hybrids over two steps (oxidation/condensation reactions). An attempt to use the other intermediate for a multistep synthesis of a [2.1]cyclophane bearing a perylene moiety failed. However, the last step of the synthesis met with a serendipitous rearrangement reaction under Scholl reaction conditions to afford an unusual [2.1]cyclophane featuring a 1,1′-binaphthalene moiety. Two plausible mechanistic pathways that have resemblance to those of the Scholl reaction have been delineated to account for the formation of the unexpected [2.1]cyclophane.


identifier: Arunthavanathan, Rajeevan <https://research.library.mun.ca/view/creator_az/Arunthavanathan=3ARajeevan=3A=3A.html>   (2022) Machine learning methods for fault detection and diagnosis of digitalized processing system.  Doctoral (PhD) thesis, Memorial University of Newfoundland.

abstract:
This thesis presents novel development and applications of machine learning techniques for process fault detection, diagnosis, and prognosis from safety and predictive maintenance perspectives. The main contributions of this thesis include the development of (i) new algorithms to diagnose the unlabelled faults; (ii) a self-learning tool for fault detection and diagnosis of untrained faults; (iii) a forecast model for fault conditions; (iv) a framework for root cause analysis in an automated environment; and (v) a methodology for estimating the remaining useful life.
In the context of Industry 4.0, process plants’ operations have become increasingly autonomous and run in an intelligent mode. An intelligent process operation takes advantage of online data, uses advanced modelling approaches and utilizes automation to achieve a flexible, smart, and reconfigurable operation. In such an autonomous environment, process fault detection, diagnosis, and prognosis play critical roles in ensuring its safety and integrity. In this study intelligent fault detection and diagnosis methods are developed based on state-of-the-art machine learning techniques. Further, this study is extended to calculate the remaining useful life online, using the fault to failure transmission time.
The research study results in five signification contributions. First, a comprehensive review of the existing fault detection and diagnosis approaches was conducted to identify the knowledge gaps and to develop fault detection and diagnosis approaches that are best suited for Industry 4.0. Second, a cognitive fault detection and diagnosis technique using unlabelled process data and an anomaly detection technique using machine learning were developed. Third, a self-learning neural network and permutation algorithm were developed for prediction of the root cause of a detected fault. Fourth, a methodology was developed to early predict faults, based on monitoring the fault
symptoms using a deep learning algorithm. Fifth, a model was developed to estimate the remaining useful life using the system’s failure threshold and a degradation model.
In this research work, all the proposed models were developed using self-learning methodologies. Therefore, the work constitutes an essential step towards developing an autonomous fault detection, diagnosis, and remaining useful life estimation tool. The proposed frameworks are validated using experimental data and simulated process system data.
The findings from this study highlight that by integrating unsupervised and supervised learning, without prior knowledge of the fault condition, the proposed machine learning model was able to detect and diagnose the fault conditions. Unsupervised learning was used to detect the unknown fault conditions, and a neural network permutation algorithm was used to identify the root cause for the detected unknown faults. This work also used supervised learning to classify the known fault conditions. Furthermore, by investigating the failure condition of the identified root cause variable or feature, remaining useful life was estimated by developing a regression model. Likewise, this thesis finds the solution for early fault detection in real-time by integrating the deep learning tools with unsupervised learning.


identifier: Blackwood, Justin <https://research.library.mun.ca/view/creator_az/Blackwood=3AJustin=3A=3A.html>   (2022) A novel technique to improve measurements in time-of-flight based acoustic tomography.  Masters thesis, Memorial University of Newfoundland.

abstract:
Understanding the changes in oceanographic conditions is important for many applications; from weather forecasting, studying the impacts of climate change and for safety considerations during operations at sea, such as offshore oil installations or offshore wind turbine sites. Many oceanographic parameters, such as temperature, current speed, salinity and pressure, can be derived using acoustic tomography techniques, which determine the time-of-flight between two points and then calculate the properties based on the bi-directional travel times.
Initial work in the field of time-of-flight acoustic tomography had focused on the mesoscale (100-1000s of kilometers). More recently, smaller scale systems have been tested that cover systems in the 100s of meters. This new range presents new challenges such as multipath propagation and the impact of timing errors on the scale of milliseconds. If these systems are to become successful, it will be essential to improve upon the precision and accuracy of the measurements obtained.
A new approach has been proposed and system developed to test its merits. This system utilizes an additional, third hydrophone to observe the waveform in the aqueous environment which is used in place of an ideal waveform in the data analysis. Where possible, to reduce sources of error, shore-side laboratory equipment was utilized for their robust prior testing and manufacturing quality and physical connections were utilized to prevent timing error.


identifier: Welsh, Cassidy <https://research.library.mun.ca/view/creator_az/Welsh=3ACassidy=3A=3A.html>   (2022) An association study exploring the genetic relationship of psoriatic arthritis and obesity.  Masters thesis, Memorial University of Newfoundland.

abstract:
Objective: To determine if there is a genetic component causing psoriatic arthritis (PsA) patients to have higher BMIs when compared to the general population.
Method: 696 obese samples were identified from a previous genetic study on obesity which were genotyped using a PsA SNP panel. 650 PsA patients who were examined for PsA related anthropometric measures were genotyped using an obesity SNP panel. An obesity panel was created using a gene prioritization method to create a 46 SNP obesity-weighted panel. Two separate quantitative trait analyses were performed to obtain the association between BMI and genotype of the subsequent panels using a linear regression model. Bonferroni correction was used to adjust for multiple comparisons.
Results: Genotypes of two PsA-weighted SNPs, rs10782001 (FBXL19) and rs3131382 (HLA-B*39), showed a significant difference with BMI. Patients with the FBXL19 variant had an average BMI in the presence of GG genotype of 37.2 kg/m² vs 34.3 kg/m² for the AA genotype (p=0.0007). Patients with the HLA-B*39:05 variant had an average BMI with the TT genotype of 47.1 kg/m2 vs 35.4 kg/m² for the CC genotype (p=0.00005). One obesity-weighted SNP, rs11915371 (SAMMSON/FOXP1), showed a significant difference of BMI between genotypes in PsA patients. The average BMI of those with the CC genotype was 32.42 kg/m² compared to an average BMI of 29.77 kg/m² with the TT genotype (p=0.0009).
Conclusion: Homozygotes for the minor allele of SNPs within HLA-B*39, FBXL19, and SAMMSON/FOXP1 have shown to have an increased BMI, suggesting a potential genetic link between these genes and PsA and obesity.