title: Development, validation, and application of a selective saliva-based cortisol biosensor

contributor: McDuffee, Laurie (Supervisory Committee Member)

contributor: Ahmadi, Ali (Examination Committee Member)

contributor: Montelpare, William (Examination Committee Member)

contributor: Whelan, William (Examination Committee Member)

contributor: Ngo, Trung Dung (Examination Committee Member)

format: electronic 99 application/pdf

abstract:
Cortisol, a steroid hormone, is essential in various physiological processes and follows a circadian rhythm throughout a day-night cycle. Abnormal levels of cortisol can be attributed to diseases, but most notably, it is caused by stress. Therefore, cortisol is widely known as a stress biomarker. Having a device to analyze salivary cortisol is essential in identifying environmental or behavioural triggers that can lead to stress. Analysis through saliva-based cortisol sensing offers a method of obtaining samples in a non-invasive form, minimizing additional stress. The current standard methods of measurements have disadvantages of being time-consuming, expensive and require specialized equipment to run the analysis, such as enzyme-linked immunosorbent assay (ELISA). Therefore, there is a need for a device that is cost-effective, fast, portable, and easy to use, thus creating a point-of-care (POC) device for the measurement of salivary cortisol.
In this thesis, a lateral flow assay (LFA) technique have been implemented for rapid quantitative analyses of salivatory cortisol. Parametric studies performed to investigate the effects of LFA preparation and construction on the measurement of cortisol sample concentrations. The studies conducted determined the characteristics of the LFA, such as sensitivity and selectivity to establish limitations and reproducibility. Horse saliva was used to test the LFA performance and was compared to an ELISA measurement. MATLAB was used in the development of an automated image processing algorithm. This algorithm enabled automated and faster measurement of cortisol in saliva through extraction of novel transient features. It was concluded that using automated image processing and advanced feature extraction a higher level of selectivity can be achieved.


title: Development of an attitude control system for CubeSat application

type: Text Dissertation/Thesis

contributor: O'Neill, Joshua Francis Reginald (author)

contributor: McSorley, Grant (Supervisory Committee Member)

contributor: Whelan, William (Supervisory Committee Member)

contributor: Bressan, Nadja (Examination Committee Member)

contributor: Krouglicof, Nicholas (Examination Committee Member)

contributor: McSorley, grant (Examination Committee Member)

contributor: Lee, James (Examination Committee Member)

format: electronic 151 application/pdf

abstract:
Guidance, navigation, and control (GNC) systems are commonly found in vehicles, whether they be spacecraft, aircraft, seacraft or landcraft. These systems are designed to bring the vehicle to its desired position and/or orientation by sensing pose and making the necessary adjustments to onboard devices. With regard to satellites, GNC systems are divided into two segments: orbit control, which is concerned with the spacecraft’s position, and attitude control, which is concerned with the spacecraft’s orientation. The focus of this thesis is to develop the attitude control system of a CubeSat nanosatellite being designed for the University of Prince Edward Island’s SpudNik-1 mission.
The objective of this study was to progress the design of the attitude control system (ACS) from its conceptual design phase to a state where it is ready for assembly, integration, and testing. To accomplish this, the engineering design process was applied. Accordingly, the fundamentals of attitude control were first reviewed in literature. Then, the system-level requirements were evaluated and the current design’s ability to meet them was assessed. After doing so, the necessary alterations were made to the conceptual design, such that it would meet the requirements, and the various methods of requirement verification were defined to verify that this is the case during the assembly, integration, and testing phase. Once the system-level design had been established, this process was repeated for the subsystem- and unit-level designs.
In addition to contributing the detailed design of an attitude control system to the Spudnik-1 team, this work can also serve as a reference for other teams working toward space missions that require the use of an ACS by providing a comprehensive perspective that focuses on the identification, integration, and implementation of the major elements of an attitude control system. It not only offers detailed information on the definition, measurement, modeling, estimation, and control of a spacecraft’s attitude, but also identifies: the connections between these concepts; the hardware used to implement the concepts in a real-world application; and the various considerations that should be taken during this implementation.
Aside from familiarizing the reader with the methodology behind an ACS system, this work also describes the procedure that was used to develop the attitude control subsystem of the SpudNik-1 CubeSat. It details: how the requirements of the attitude control subsystem were identified from the spacecraft’s mission and the corresponding system requirements; how the major components and concepts of the ACS are identified from the subsystem requirements, and integrated through the subsystem architecture; how the unit-level requirements are identified based on the subsystem-level design; and how the implementation of the various components and concepts is dependent on the unit level requirements.
While a good deal of the design is standard with regard to CubeSats and other aerospace projects, the original aspects would relate to the in-house design of the reaction wheels and fine sun sensors. Being as there are a wide selection of ACS components available on the market, it is most common for CubeSat projects to procure their hardware. Although the lack of flight heritage did pose additional risk to the mission in comparison to using commercial equipment, the in-house design allowed the components to be both tailored to the mission and produced at a fraction of the cost. If the designs manage to gain flight heritage on-board of the SpudNik-1 CubeSat, then this work will provide readers with standard frameworks which will allow them to reap the same benefits, but at a lower level of risk.


title: The development and validation of a scale to measure climate change anxiety

contributor: Antadze, Nino (Supervisory Committee Member)

contributor: Strong, Jessica V. (Examination Committee Member)

contributor: Doiron, Jason (Examination Committee Member)

contributor: Arfken, Michael (Examination Committee Member)

contributor: Antadze, Nino (Examination Committee Member)

contributor: MacDonald, Brent (Examination Committee Member)

abstract:
Climate change – the rapid changes to Earth’s climate system related to anthropogenic influence – has had widespread effects on humans and the natural world (Intergovernmental Panel on Climate Change [IPCC], 2022). Research suggests that psychological effects of climate change are becoming more common as more people become aware of climate change (Searle & Gow, 2010). This includes climate change anxiety, defined as anxiety in response to knowledge of the threat of climate change. To address the growing incidence of climate change anxiety, we must be able to accurately assess the problem. Informed by the psychological literature, the present study involved the development and validation of a scale to measure climate change anxiety at adaptive and maladaptive levels. Exploratory factor analysis revealed a three-factor solution, with subscales measuring clinical significance of anxiety, existential anxiety, and cognitive, future-focused anxiety respectively. The study also explored relationships between climate change anxiety and other constructs, including climate-related knowledge, climate action, and experience with climate change events. The development of this evidence-based scale
will allow for the accurate assessment of climate change anxiety which may help to inform treatment of those that experience debilitating levels of climate change anxiety.


title: Machine learning based climate projections for sustainable potato production in Prince Edward Island

contributor: Wang, Xander (Supervisory Committee Member)

contributor: Acharya, Bishnu (Supervisory Committee Member)

contributor: Farooque, Aitazaz (Examination Committee Member)

contributor: Acharya, Bishnu (Examination Committee Member)

contributor: Wang, Xander (Examination Committee Member)

contributor: Prasher, Shiv O. (Examination Committee Member)

contributor: Ahmadi, Ali (Examination Committee Member)

format: electronic 92 application/pdf

abstract:
Prince Edward Island (PEI) is the largest potato-producing province in Canada, and most of its croplands are rainfed. Climate change impacts all fields of life, including agriculture. Thus, there is a need to understand better the historical variations and future projections of climate change and its patterns for PEI. Climate change and its impacts on potato tuber yield have been evaluated in this thesis under three objectives. For the first objective, twenty climate extreme indices were computed with the help of ClimPACT2 software for 30 years (1989-2018) to assess their impacts on the potato tuber yield.
The average of daily mean temperature, mean daily minimum temperature (TNm), and the occurrence of continuous dry days (CDD) significantly increased, while daily temperature range (DTR), frost days, cold days, cold nights, and warmest days (TXx) showed decreasing trends during the potato growing seasons (May-October) for the past three decades. The principal component analysis results showed that DTR, TXx, CDD, and TNm were the main indices, defining ~39% variations in tuber yield. However, DTR, TXx, CDD, and TNm individual contributions to the variations in tuber yield were recorded to be 21, 19, 16, and 4%, respectively. For the second objective, the Hargreaves method was used to calculate reference evapotranspiration (ET0) for western, central, and eastern parts of PEI using their two input parameters: daily maximum temperature (Tmax) and daily minimum temperature (Tmin). The Tmax and Tmin from the Canadian Earth System Model Second Generation (CanESM2) were downscaled with the help of statistical downscaling model (SDSM) for three future periods, i.e., the 2020s (2011-2040), 2050s (2041-2070), and 2080s (2071-2100) under three representative concentration pathways (RCP’s) including RCP2.6, 4.5, and 8.5. Temporally, there were major changes in Tmax, Tmin, and ET0 for the 2080s under RCP8.5. In the next steps, a one-dimensional convolutional neural network (1D-CNN), long-short term memory (LSTM), and multilayer perceptron (MLP) were used for estimating ET0 for historical and future periods. High coefficient of correlation (r > 0.95) values for both calibration and validation periods showed the potential of the artificial neural networks in ET0 estimation. For the third objective, SDSM, MLP, random forest (RF), and support vector regression (SVR) were used to downscale Tmax, Tmin, and precipitation at eight meteorological stations located in PEI. The comparison results depicted the better performance of MLP to downscale the climatic parameters (Tmax, Tmin, and precipitation). Therefore, the MLP algorithm was used to project the climatic parameters for the future period (2006-2100) under RCP2.6, 4.5, and 8.5. The linear scaling method was used to reduce the biases in the projected data and get real results. The results of the analysis of the data from the annual and the growing season showed that Tmax and Tmin continually increased in the future under all the RCPs, but maximum increment was noticed under RCP8.5. The spatial patterns of average annual precipitation in the growing season showed high, moderate, and low precipitation at the PEI’s eastern, central, and western parts for the historical (1976-2003) and future periods. This study will help the decision-makers and farmers to understand better the variations and patterns of the climatic parameters for the historical and future periods in relation to agriculture. The results may also help to develop irrigation scheduling in response to climate change to meet sustainable development goals.


title: Applications of simulation modelling to inform viral disease management in Canadian salmon aquaculture

contributor: Davidson, Jeffrey (Supervisory Committee Member)

contributor: Groman, David (Supervisory Committee Member)

contributor: Price, Derek (Supervisory Committee Member)

contributor: Overall, Karen (Examination Committee Member)

contributor: Peeler, Edmund (Examination Committee Member)

contributor: Groman, David (Examination Committee Member)

contributor: Gardner, Ian (Examination Committee Member)

contributor: Saksida, Sonja (Examination Committee Member)

format: electronic 262 application/pdf

abstract:
Infectious diseases are responsible for substantial economic losses in salmon aquaculture due to production losses from mortality, morbidity and reduced growth rates, and costs of outbreak prevention and mitigation. Two of the most concerning viral diseases affecting farmed salmon in Canada are infectious salmon anaemia (ISA) and infectious hematopoietic necrosis (IHN). These are region-specific in Canada, as ISA occurs in the Atlantic coast, while IHN is present in the Pacific coast. Despite epidemiologic differences between the two viruses, both can be transmitted between marine salmon farms in the water column. However, limited research has been conducted on the transmission dynamics of ISA virus (ISAV) and IHN virus (IHNV) among marine farmed salmon populations in Canada. Furthermore, some aspects of ISAV epidemiology and cost- effectiveness of its mitigation in Atlantic Canada require further investigation.
Research documented in this thesis aimed to provide additional insights about the epidemiology of ISAV in Atlantic Canada. A population-level descriptive study reported epidemiologic findings of an ISAV outbreak in the region. In two of the affected marine salmon farms both European and North American ISAV variants were simultaneously detected. In addition, we found presumptive evidence of emergence of a pathogenic ISAV variant from a non-pathogenic variant of the same genotype, based on detection of co- infection in one fish.
A simulation modelling framework was developed for the purpose of investigating the dynamics of waterborne pathogen transmission in marine salmon aquaculture. This framework allowed for development of models that simulate waterborne infection spread within net-pens, and between net-pens (both within and between farm sites), as well as surveillance, detection, and depopulation measures. Technical characteristics and structure of the framework were described, and a case study demonstrated the framework functionalities. This simulation tool addresses the lack of simulation models intrinsically adapted to the aquaculture context.
The newly-developed modelling framework was used to simulate IHNV incursions and subsequent spread along the coast of British Columbia and the implementation of a viral disease management plan (VDMP) by salmon companies. Different scenarios were explored to assess VDMP effectiveness compared with alternative mitigation measures. Research findings indicated that interventions crucial to contain IHN outbreaks were the use of an IHN vaccine with high population coverage and efficacy, the implementation of surveillance zones, and the pre-emptive depopulation of all net-pens in IHNV-infected farms. Comparisons between simulated scenarios indicated that the VDMP was effective in limiting IHNV spread and mitigating outbreaks across the region.
Finally, to help the salmon aquaculture industry plan for expansion of production capacity in Atlantic Canada, a simulation modelling approach was used to assess the cost- effectiveness of ISAV outbreak mitigation strategies, considering different percentages of active licensed farms. For each model scenario, direct costs of ISAV mitigation interventions were estimated from model outputs. Results demonstrated the importance of pre-emptive depopulation of all net-pens in ISAV-positive farms to effectively limit ISAV spread; however, this strategy increased costs of ISAV mitigation as production capacity expanded, suggesting that a moderate capacity increase (65% compared with 40% active farms) would be more cost-effective than a high capacity increase (90% active farms). Nevertheless, a cost-benefit analysis should be explored to substantiate this recommendation.
This research demonstrates the value of descriptive epidemiologic studies and simulation modelling in aquatic health management. Ultimately, research findings documented herein provide insights to inform policy and disease management decisions to reduce viral disease risk in Canadian salmon aquaculture.


title: Simulation models for between farm transmission of PRRS virus in Canadian swine herds

contributor: Hurnik, Daniel (Supervisory Committee Member)

contributor: Sanchez, Javier (Supervisory Committee Member)

contributor: Revie, Crawford (Supervisory Committee Member)

contributor: Opps, Sheldon (Supervisory Committee Member)

contributor: Poljak, Zvonimir (Supervisory Committee Member)

contributor: Hammell, Larry (Examination Committee Member)

contributor: Waldner, Cheryl (Examination Committee Member)

contributor: Hurnik, Dan (Examination Committee Member)

contributor: Opps, Sheldon (Examination Committee Member)

format: electronic 257 application/pdf PUBLISHED

abstract:
Porcine reproductive and respiratory syndrome (PRRS) is a viral disease of pigs, which affects all production stages and has severe economic consequences for the swine industry. The virus is primarily spread between farms through direct and indirect contacts. A limited number of studies have been carried out to understand the between-farm transmission dynamics of the virus. The objectives of this thesis were to explore the contact structures among swine farms in Canada and to use these contact structures to better understand the pattern and dynamics of between-farm spread of PRRS virus among Canadian swine herds.
Four different studies were designed and implemented to achieve these objectives. The first study used network analysis tools to analyse pig movement data which revealed characteristics of contact patterns between swine herds and suggested a hierarchical structure within the Canadian swine industry, where pigs typically move in a unidirectional manner from one production stage to another. The median in-degree and out-degree for farms in this study was 1 and ranged between 0-26 and 0-10 respectively for the overall network. The degree distributions demonstrated characteristics of a power-law distribution, suggesting the presence of scale-free structure while the size of clustering coefficient suggested presence of small-world structure in the swine movement network. Additionally, high levels of truck sharing between farms were noted in this study, with a typical truck, during the study period, being shared among four different farms. The second and third studies simulated the between farm spread of the PRRS based on the movement of pigs and the sharing of trucks among swine farms, using the North American Animal Disease Spread Model and the network-based models respectively. These studies provided a means to assess the relative importance of direct and indirect contact via truck sharing on between farm spread of PRRS virus. By including the transmission by trucks in the model, the median number of infected farms increased by 18% and the median epidemic size increased by 44% in the spatial model. Furthermore, with the addition of trucks in the model, the hierarchical structure of the industry was significantly altered and multidirectional disease spread was observed. On the other hand, the network-based models assessed the impact of scale-free, small-world and random network structures on the between farm spread of PRRS virus and demonstrated the influence these network structures can have on the spread of the virus. The spread on scale-free networks resulted in the smallest stochastic die-out percentage with highest epidemic sizes compared to spread on small-world or random networks. Similarly, the incorporation of transmission by trucks in the model had the highest impact on small-world and random networks, where the epidemic size doubled, compared to scale-free networks, where it increased by 20-29%. Given the importance of transmission of the virus via truck (e.g. indirect contacts) identified in the previous studies, the last chapter aims at (i) quantifying the likelihood that a pig transport truck shared among farms could remain contaminated with PRRS virus at the end of Day 1 and to (ii) evaluate the efficacy of commonly used cleaning and disinfection protocols in eliminating the virus from these trucks. The results of this study suggested, when no cleaning and disinfection protocol is applied, that it is moderately likely that the truck could become contaminated and remain infected with the PRRS virus (mean probability ranged between 0.338-0.352, when the truck was shared between two farms), and that this risk marginally increased with an increase in the number of farms the truck was shared among. This final study also suggested that once contaminated, most of the contaminated trucks would likely remain infected for more than one day.
The studies presented in this thesis have not only provided a clearer insight into the pattern of contacts between farms, and the impact these contacts can have on PRRS virus spread, but have also highlighted the importance of including data on the sharing of trucks among farms, since trucks will tend to connect farms which would otherwise share no connection. Moreover, the studies in this thesis have reinforced the importance of the proper cleaning and disinfection of trucks between successive shipments, as the findings presented here suggest that with an increasing level of truck sharing between farms, shared trucks are likely to remain contaminated with the virus and sharing of trucks significantly increased the risk of between farm spread of PRRS virus. Not only do the shared trucks have a high probability of becoming contaminated with the virus, but once contaminated, they are likely to remain infected for a comparatively long period particularly in the absence of adequate disinfection. It should be noted that the pig movement data used in this study was not very recent and consisted of movements reported for only four months time period. Additionally, the described models could not be validated due to unavailability of data is another noteworthy limitation of the studies described in this thesis.


title: Pathogenesis of frog virus 3 (Ranavirus sp, Iridoviridae) in the wood frog, Rana sylvatica (Lithobates sylvaticus)

contributor: Forzán Gómez, María de Jesús (author)

contributor: Kibenge, Fred (Supervisory Committee Member)

contributor: Daoust, Pierre-Yves (Supervisory Committee Member)

contributor: Markham, Fred (Supervisory Committee Member)

contributor: Hogan, Natacha (Supervisory Committee Member)

contributor: Kuiken, Thijs (Supervisory Committee Member)

contributor: Smith, Todd (Supervisory Committee Member)

contributor: Daoust, Pierre-Yves (Examination Committee Member)

contributor: Rodriguez, Juan Carlos (Examination Committee Member)

contributor: Smith, Todd (Examination Committee Member)

contributor: Martel, An (Examination Committee Member)

contributor: Aburto, Enrique (Examination Committee Member)

format: electronic 195 application/pdf PUBLISHED

abstract: Amphibian populations suffer massive mortalities from infection with Frog Virus 3 (FV3,  Ranavirus, Iridoviridae), a pathogen also responsible for mortalities of fish and reptiles.   Wood frogs, Rana sylvatica, have been proposed as a research model to study diseases  of native amphibians in North America.  Our objectives were: 1) describe the longbterm  housing, feeding and veterinary care of wildbcaught wood frogs, 2) develop a Ranavirusb wood frog model of infection with FV3, 3) review the literature on amphibian clinical  pathology, 4) determine hematological reference intervals (RIs) for adult wood frogs and  the hematological alterations associated with infection with FV3, and 5) establish the  chronology of lesions due to a lethal infection with FV3.  Wildbcaught adults and tadpoles were collected from Prince Edward Island and  maintained in captivity for up to a year.  Survival was good for wildbcaught individuals:  75 % for wildbcaught adults and 77 % for tadpoles raised to adulthood.  A dose trial on adults raised from wildbcaught tadpoles established a lethal dose 50  (LD50) of 102.93 (2.42b3.44) pfu of FV3 for frogs averaging 35 mm in length. Onset of clinical  signs occurred 6b14 days postbinfection (dpi) (median 11 dpi) and timebtobdeath 10b14  dpi (median 12 dpi). Each tenbfold increase in virus dose increased the odds of dying by  23bfold and accelerated onset of clinical signs and death by approximately 15%.   Ranavirus DNA was demonstrated in skin and liver of all frogs that died or were  euthanized because of severe clinical signs.  Shedding of virus occurred in feces (7b10  dpi; 3b4.5 d before death) and skin sheds (10 dpi; 0b1.5 d before death) of some frogs  that died from infection.  Most common lesions were dermal erosion and hemorrhages,  hematopoietic necrosis in bone marrow, kidney, spleen and liver, necrosis in renal  glomeruli and in tongue, gastrointestinal tract, and urinary bladder mucosa.   Intracytoplasmic inclusion bodies (probably viral) were present in the bone marrow and  the epithelia of the oral cavity, gastrointestinal tract, renal tubules and urinary bladder.  A timebcourse trial on wildbcaught adults using a lethal dose of FV3 (104.43 pfu/frog)  followed by euthanasia at 0.25, 0.5, 1, 2, 4, 9 and 14 dpi established pathogenesis and hematological alterations due to infection.  Infection with FV3 caused neutrophilia,  increase in undifferentiated blastblike cells and relative reduction of basophils.   Lymphocytes decreased at 4 and 9 dpi but increased 14 dpi.  From 9 dpi onwards,  nuclear deterioration and mild toxic change were present in neutrophils; cytoplasmic  inclusion bodies were present in lymphocytes, monocytes, neutrophils and eosinophils.  FV3 first targets hematopoietic tissue in the bone marrow and endothelial cells in the  skin causing very mild microscopic lesions (1b2 dpi).  Approximately 9 dpi, FV3 caused  severe lesions in medullary and extamedullary hematopoietic tissue, lymphoid tissue  and epithelial cells of skin and mucosae throughout the body.  Direct contact (skin) and  fecalboral contamination are likely effective routes of transmission.


title: "The circumscribed geography of home": Island identity in the fiction of Alistair MacLeod and Wayne Johnston

contributor: MacLaine, Brent (Supervisory Committee Member)

contributor: Mitchell, Jean (Supervisory Committee Member)

contributor: Lyons, Jeanette (Supervisory Committee Member)

format: print 145 application/pdf PUBLISHED

abstract:
This thesis addresses issues of islandness and island identity in the fiction of Cape Breton's
Alistair MacLeod and Newfoundland's Wayne Johnston. Through careful readings of their
fiction, with supplementary evidence culled from biographical and secondary sources, the thesis
shows that their work is profoundly influenced by their childhood experiences; that these authors
have been "imprinted" by growing up on an island; and that, as a result, both authors bear a
strong island identity which inspires and infuses their writings. The thesis opens by introducing
themes that pervade islandness, and proceeds to set MacLeod's and Johnston's fiction in the
context of the western traditions of island and regionalist literature, followed by a discussion of
how identity is formulated. In three chapters the thesis explores the theme of boundedness:
physically or geographically, in the ways that the ocean's boundary defines a character, as
evidenced primarily in Johnston’s The Colony of Unrequited Dreams and MacLeod’s "Island";
psychologically, in the ways that childhood and family affect an individual growing up on an
island, as evidenced primarily in Johnston's The Story of Bobby O’Malley and MacLeod’s "The
Boat" and "The Lost Salt Gift of Blood"; and emotionally, in the ways that social influences
affect feelings of belonging and exile, as evidenced primarily in Johnston’s The Custodian of
Paradise and MacLeod’s No Great Mischief. The thesis concludes with a reaffirmation of the
influence of islandness and island identity in the fiction of Alistair MacLeod and Wayne
Johnston.


title: "Almost islands": A research synthesis of Aboriginal communities in Canada as metaphorical islands

contributor: Randall, James (Supervisory Committee Member)

contributor: Baldacchino, Godfrey (Supervisory Committee Member)

contributor: Preston, Jane (Supervisory Committee Member)

contributor: Randall, James (Examination Committee Member)

contributor: Baldacchino, Godfrey (Examination Committee Member)

contributor: Preston, Jane (Examination Committee Member)

contributor: Fox, Michael (Examination Committee Member)

format: 178 application/pdf PUBLISHED electronic

coverage:
Canada
Ethnic identity.
Canada
Social conditions.
Effect of environment on
Canada.
Canada
Canada
Social conditions.
Canada

rights: In presenting this thesis in partial fulfilment of the requirements for a graduate degree from the University of Prince Edward Island, the author has agreed that the Robertson Library, University of Prince Edward Island, may make this thesis freely available for inspection and gives permission to add an electronic version of the thesis to the Digital Repository at the University of Prince Edward Island. Moreover the author further agrees that permission for extensive copying of this thesis for scholarly purposes may be granted by the professor or professors who supervised the author’s thesis work, or, in their absence, by the Chair of the Department or the Dean of the Faculty in which the author’s thesis work was done. It is understood that any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without the author’s written permission. It is also understood that due recognition shall be given to the author and to the University of Prince Edward Island in any scholarly use which may be made of any material in the author’s thesis.

subject: Native peoples

subject: Native peoples--Canada--Ethnic identity.

subject: Native peoples

subject: Native peoples--Canada--Social conditions.

subject: Human beings

subject: Human beings--Effect of environment on--Canada.

subject: Cultural geography

subject: Cultural geography--Canada

subject: Island people

subject: Island people--Canada--Social conditions.

subject: Social isolation

subject: Social isolation--Canada

abstract: The purpose of this study is to describe the geographic distribution of Aboriginal people who live in remote, isolated Aboriginal communities in Canada in terms of how geographic settings and features, particularly those that are characteristic of island dwellers, are related to and can impact aspects of culture and identity. Through this process, data was collected using a research synthesis, which allowed for a great deal of data from various sources to be analyzed, extracted, and coded. Based on this qualitative study, numerous geographic characteristics similar to those of islanders and islands emerged. Physically, islands and Aboriginal communities represent bounded, finite spaces that are located on the periphery and are impacted by isolation. These unique isolated areas allow for islanders and Aboriginal people to experience ethnic homogeneity and strong attachments to place, both of which allow for the preservation of culture and identity. That being said, islanders and Aboriginal people both experience migration as a way of life, and leaving their places of origin to experience life in larger, more diversely and densely populated areas is necessary for many. As a result of these findings, this study compares isolated Aboriginal communities in Canada and Aboriginal people to various small islands around the world as well as islanders, through various spatial metaphors.


title: Long chain n-3 polyunsaturated fatty acid inhibition of mast cell activation

contributor: Saleh, Tarek (Supervisory Committee Member)

contributor: Kulka, Marianna (Supervisory Committee Member)

contributor: Burka, John (Supervisory Committee Member)

contributor: Markham, Fred (Supervisory Committee Member)

contributor: Wang, Yanwen (Supervisory Committee Member)

contributor: Kulka, Marianna (Examination Committee Member)

contributor: Field, Catherine (Examination Committee Member)

contributor: Markham, Fred (Examination Committee Member)

contributor: Bate, Luis A (Examination Committee Member)

contributor: McConkey, Sandra (Examination Committee Member)

format: electronic 229 application/pdf PUBLISHED

rights: In presenting this thesis in partial fulfillment of the requirements for a postgraduate degree from the University of Prince Edward Island, I agree that the Libraries of this University may make it freely available for inspection. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the professors who supervised my thesis work, or, in their absence, by the Chair of the Department or the Dean of the Faculty in which my thesis work was done. It is understood any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of Prince Edward Island in any scholarly use which may be made of any material in my thesis.

abstract:
Allergic diseases are a major medical concern with increasing prevalence in the world. Inflammation is one of the hallmarks of allergic diseases. Long chain n-3 polyunsaturated fatty acids (PUFAs) have been shown to inhibit allergic inflammation, but their direct effect on activation of the mast cell, a major effector cell in allergic inflammation, is poorly understood. We hypothesized that long chain n-3 PUFAs inhibit mast cell activation through alteration of the expression of some signaling molecules and modification of Fc ε receptor I (FcεRI) association with lipid rafts, membrane microdomains containing high levels of cholesterol, sphingolipid, transmembrane proteins, acylated proteins, and glycosylphosphatidylinisotol (GPI)-anchored proteins. Bone marrow-derived mast cells (BMMC) were cultivated from C57BL/6 wild type (WT) and fat-1 transgenic mice which express fatty acid n-3 desaturase and produce endogenous n-3 PUFAs. Exogenously, long chain n-3 PUFAs were supplemented to BMMC and human mast cell line laboratory of allergic diseases 2 (LAD2) cells. Mast cell degranulation, lipid-derived mediator release, and cytokine/chemokine production were evaluated following cell activation through FcεRI. FcεRI expression and signal transduction was determined by flow cytometry and western blot analysis.
GC-MS analysis showed increased long chain n-3 PUFAs levels in whole cell and lipid rafts of fat-1 BMMC, compared to WT, and in whole cell long chain n-3 PUFA-treated BMMC. Fat-1 BMMC produced less tumor necrosis factor (TNF) and CC chemokine ligand 2 (CCL2), and cysteinyl leukotrienes (cys-LTs), and showed reduced degranulation compared to WT BMMC after cell stimulation with immunoglobulin E (IgE)/antigen. Long chain n-3 PUFA exogenous supplementation caused decreased
degranulation, cys-LT synthesis and cytokine/chemokine production in activated BMMC and LAD2 cells. Western blot analysis showed that the expression of Lyn and linker for activation of T cells (LAT) and phosphorylation of Lyn and spleen tyrosine kinase (Syk) and LAT was inhibited in fat-1 BMMC compared to WT. In both BMMC and LAD2 cells, long chain n-3 PUFAs did not alter cell surface and whole cell FcεRI expression. However, FcεRI was excluded from lipid rafts by long chain n-3 PUFAs in resting mast cells. Furthermore, the shuttling of FcεRI to rafts of activated mast cells was inhibited by long chain n-3 PUFAs. After lipid raft disruption by depleting cholesterol, mast cell degranulation, cys-LT release and cytokine/chemokine production were reduced in both WT and fat-1 BMMC. In addition, FcεRI and Lyn localization to lipid rafts were suppressed by MBCD treatment. This study clearly indicates that long chain n-3 PUFAs inhibit FcεRI-mediated signal transduction and mediator release from mast cells by disrupting FcεRI localization and partitioning to lipid rafts, and supressing the expression of Lyn and LAT. Cholesterol is required for the inhibitory effect of long chain n-3 PUFAs on mast cell activation.


title: "Angels in the Marble": Voices of immigrant youth on Prince Edward Island

contributor: Turnbull, Miles (Supervisory Committee Member)

contributor: Doiron, Ray (Supervisory Committee Member)

contributor: Turnbull, Miles (Examination Committee Member)

contributor: Doiron, Ray (Examination Committee Member)

format: electronic 163 application/pdf PUBLISHED

abstract:
This qualitative case study examined the lived experiences of 4 secondary English as Additional
Language (EAL) students in Prince Edward Island schools and communities. More specifically,
participants shared their perspectives on their unique and sometimes painful experiences in PEI
secondary schools and communities. The following 2 research questions guided this research:
 What factors do EAL students say contribute to their successes in the PEI school system
and community?
 What barriers do EAL students say inhibit their successes in the PEI school system and
community?
Students participated in 2 in-depth research conversations of approximately 60 minutes
each. Data were collected, analysed, compared and contrasted, using qualitative data collection
and analysis techniques in order to respond to research questions which ultimately examined the
contributing factors to the participants‘ successes as well as barriers to successes in the PEI
school system and community. The second research conversation included the 4 participants‘
photographs they took and described as representations of their experiences in PEI secondary
schools and communities. These representations were often symbolic objects (e.g., a letter,
artwork, instrument, ethnic food) that had particular significance for each of the participants.
Similarities and differences among the responses were assessed and compared while
taking account of students‘ English language levels, socio-economic status, educational and
personal experiences, and length of time in Canada. Emerging themes, which examined the
contributing factors to their successes and barriers, included: loneliness; isolation; English
language level as a barrier; social networking; communication; engagement and disengagement; motivation for moving; and, the loss of identity, culture and language. The data further revealed
that 3 out of the 4 participants noted their biggest successes as making friends and doing well in
school in at least one or more subjects. In contrast, all 4 participants noted their low or lower
English language level was a significant barrier which ultimately affected their ability to
communicate. As a result, they experienced loneliness and isolation and did not feel they made
meaningful Canadian friendships. Marginalization and exclusion occurred in the 2 secondary
schools the EAL participants attended. Moreover, participants cited their low English level as
having a direct impact on their ability to participate in classes and comprehend the teacher and
the material. They attributed lower grades, especially in English classes, as a result of their
lower English language proficiency level.
Practical implications are discussed in relation to current research literature and previous
studies. Specific recommendations to create more successes for secondary EAL students and to
eliminate identified barriers to their successes are included.


title: Changes in Lepeophtheirus salmonis gene expression during host switching and selection

contributor: Kibenge, Frederick (Supervisory Committee Member)

contributor: Fast, Mark (Supervisory Committee Member)

contributor: Conboy, Gary (Supervisory Committee Member)

contributor: Greenwood, Spencer (Supervisory Committee Member)

contributor: Whyte, Shona (Supervisory Committee Member)

contributor: Fast, Mark (Examination Committee Member)

contributor: Greenwood, Spencer (Examination Committee Member)

contributor: Conboy, Gary (Examination Committee Member)

contributor: Byrne, Phil (Examination Committee Member)

contributor: Groman, David (Examination Committee Member)

format: electronic 152 application/pdf PUBLISHED

rights: In presenting this thesis in partial fulfilment of the requirements for a graduate degree from the University of Prince Edward Island, the author has agreed that the Robertson Library, University of Prince Edward Island, may make this thesis freely available for inspection and gives permission to add an electronic version of the thesis to the Digital Repository at the University of Prince Edward Island.  Moreover the author further agrees that permission for extensive copying of this thesis for scholarly purposes may be granted by the professor or professors who supervised the author’s thesis work, or, in their absence, by the Chair of the Department or the Dean of the Faculty in which the author’s thesis work was done.  It is understood that any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without the author’s written permission.  It is also understood that due recognition shall be given to the author and to the University of Prince Edward Island in any scholarly use which may be made of any material in the author’s thesis.

abstract:
Lepeophtheirus salmonis is a copepod parasite of salmonid fish, commonly referred to as sea lice, and is particularly pathogenic to Atlantic salmon (Salmo salar). Although endemic on wild salmon, L. salmonis infection intensity rarely reaches clinical disease levels in wild fish. The stationary nature and high density stocking of Atlantic salmon in marine aquaculture allows the intensity of L. salmonis infection to reach clinical disease levels. In certain areas, during high levels of infection, salmon often develop gross lesions, most commonly on the head, dorsal and perianal regions. The lesions, coupled with the stress induced by infection, can result in decreased feeding, secondary infections and mortality of fish. Over the past 40 years a number of chemotherapeutants have been used to control L. salmonis infection in farmed fish, however, reliance on a relatively small number of treatments has driven the development of drug resistant populations of L. salmonis.
Due to the high cost of developing new drugs, whose use may be limited by resistance development or environmental impacts, development of alternative treatment methods is becoming a necessary research avenue. Preliminary studies have shown that release of compounds derived from non-salmonid fish can reduce infection of salmon. The content of this thesis has the dual goal of trying to elucidate some of the behaviours of adult L. salmonis during host switching, and the development of an in vitro assay to assess the effects of the anti-attachment compound allyl isothiocyanate.
Host switching behaviour was assessed using a cohabitation of L. salmonis infected and uninfected fish. It was found that male lice reached an equal distribution between the two populations of fish, while female lice did not switch hosts. This equal distribution of male lice is suggested to increase access of each lice to food and potential mates. Eight genes associated with various facets of lice survival underwent gene expression analysis (CYP18 A1-like gene, Trypsin-1, tissue plasminogen activator precursor-like (TPAP)-like gene, cyptochrome p450 isoform 1-like gene, peroxinectin-like gene, leukocyte receptor cluster member 9-like (LRCM9) gene, glycene receptor α-2-like gene, and a nicotinic acetylcholine receptor subunit-like (nAChR) gene) and five salmon genes associated with immune status were analysed (Interleukin (IL)-1β, IL-8, IL-12, IgT, and Matrix Metalloproteinase 9 (MMP9)) in an attempt to reveal patterns in gene expression during host colonization. Only one instance of significant difference occurred during the study, between MMP9 in the spleen of initially infected salmon and the spleen of initially uninfected salmon at 2 days post cohabitation. It was thought that the variability in gene expression of individual lice and fish that accompanied the use of outbred populations may have masked potential changes in gene expression. Pearson correlations were used to compare gene expression between individual lice and its respective host; expression of a peroxinectin-like gene had several instances of significant correlation with expression of host genes. This is thought to be caused either by peroxinectin-like having a role in modulation of host immune response, or by peroxinectin-like being expressed in response to the salmon reaction to infection. It appears that fish with low infection have more instances of significant correlation with several L. salmonis than fish with high infection levels.
In vitro bioassays designed to assess lice response to allyl isothiocyanate revealed that adult and copepodid lice experienced increased mortality in higher treatment doses (>1ppm). Gene expression of 7 genes associated with different facets of survival were analyzed for dose dependent effects of allyl isothiocyanate on L. salmonis. The outcomes of this study suggests allyl isothiocyanate causes a significant amount of stress to L. salmonis, possibly causing the initiation of an immune response (increased then decreased LRCM9-like gene), reduced feeding (decreased Trypsin-1), and a nociceptive response (increased nAChR-like gene). Immobility was observed in lice at the high dose treatment, which is not necessarily one of the intended endpoints and may not be an achievable concentration in any management strategy, but provides evidence to suggest that exposure to allyl isothiocyanate may induce avoidance behaviour, reduce potential settlement on the host, and ultimately have a negative impact on lice survival.


title: Healthy living: perspectives from adult women in a rural context

contributor: Gabriel, Martha (Supervisory Committee Member)

contributor: Gabriel, Martha (Examination Committee Member)

contributor: MacLellan, Deborah (Examination Committee Member)

contributor: MacLellan, Deborah (Supervisory Committee Member)

format: electronic 126 application/pdf PUBLISHED

rights: In presenting this thesis in partial fulfillment of the requirements for a postgraduate degree from the University of Prince Edward Island, I agree that the Library of this University may make it freely available for inspection. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the professor or professors who supervised my thesis work, or in their absence, by the Dean of the Faculty of Education. It is understood any copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed without my written permission. It is also understood that due recognition shall be given to me and to the University of Prince Edward Island in any scholarly use which may be made of any material in my thesis.

abstract: The purpose of this study was to explore what healthy living means to adult women living in a rural area of a Canadian province. This study examined the benefits and barriers identified by the participants in relationship to healthy lifestyles, as well as the facilitators they recognized in relation to healthy living. Eight women, aged 40-65, from Prince Edward Island took part in the study. Using a descriptive, qualitative approach, data was collected through in-depth interviews. Interview data were transcribed verbatim and analyzed for common themes. Results indicated that the participant’s ideas about healthy living included eating in a healthy way, being physically active, experiencing a personal spirituality, and not having addictions to substances. The participants identified a range of factors that facilitated living a healthy lifestyle including: having balance, having confidence in oneself, being in control, supportive family members and friends, spirituality, and public policy. The participants believed that the benefits of a healthy lifestyle involved alleviating stress, enjoying life, having more energy, and being sick less often. The participants identified a number of barriers to living a healthy lifestyle as well. These include a lack of energy and motivation, stress, a lack of time, conditions in the workplace, the location of the exercise facilities, the size of the community, the cost of food, and the lack of support from family and friends. This research study calls for rethinking the education and teaching strategies used to educate women in the area of healthy living. These strategies should be reframed to address the learner as a whole, thus incorporating the physical, mental, and spiritual aspects of lifestyle choices, with a focus on the physical and socio-cultural environments in which individuals live.


title: Health and productivity monitoring of cage-cultured Atlantic halibut (Hippoglossus hippoglossus)

contributor: Sanchez, Javier (Supervisory Committee Member)

contributor: Hammell, Larry (Supervisory Committee Member)

contributor: Hurnik, Daniel (Examination Committee Member)

contributor: Gardner, Ian (Examination Committee Member)

contributor: Sanchez, Javier (Examination Committee Member)

contributor: Brown, Nick (Examination Committee Member)

contributor: McClure, Carol (Supervisory Committee Member)

contributor: Beattie, Michael (Supervisory Committee Member)

contributor: Benfey, Tillmann (Supervisory Committee Member)

format: electronic 226 application/pdf PUBLISHED

abstract:
The Atlantic Canadian aquaculture industry is dominated by Atlantic salmon production. In recent years, infectious disease, parasitic infestations, and price fluctuations from international competition have caused disruptions to the industry. Diversification of the industry away from Atlantic salmon production is a potential strategy to insulate the industry from these fish health and market challenges. Atlantic halibut has long been a primary candidate for this diversification. However, the early commercialization of the species over the last 15 years has failed to reach its potential, owning primarily to a lack of information on the biology of the species, best management practices and proven economic feasibility.
To address this information gap, a multi-objective Randomized Controlled Trial (RCT) was conducted at a commercial farm on the Bay of Fundy in New Brunswick. The study collected detailed information on the growth and survival of 5000 Atlantic halibut individually identified with Passive Integrated Transponder (PIT) tags and followed over a four year grow-out period.
The main objectives of this research were: (1) to evaluate the impact of individual fish characteristics on growth, survival and farm economics, (2) to determine the effects of oil-adjuvanted vaccines on growth performance, survival and vaccine associated lesions, (3) to evaluate the suitability of FT4 Lock-on tags as an external tagging method for individual identification of Atlantic halibut, and (4) to test a Stratified Transport System (STS) as a means of improving fish welfare and the economics of overland halibut transport.
A variety of fish level characteristics were found to be important predictors of productivity. Identifying and culling fish with these specific characteristics prior to grow-out was identified as a method to improve overall farm productivity. The side-effects of oil-adjuvanted vaccines were found to be mild in Atlantic halibut, thereby identifying oil-adjuvants as an available tool for future vaccine development. FT4 Lock-on tags were found to be suitable for identifying cage-cultured halibut with the exception of substantial impacts on growth. The STS was demonstrated to reduce post-transport mortality, establishing it as a cost-effective transport solution over currently practiced methods.
In conclusion, this research allows producers to make evidence-based management decisions, to strengthen and facilitate the continued development of the Atlantic halibut aquaculture sector in Atlantic Canada.


title: Sustaining island fishing communities: Policy and management in practice in Maine and Newfoundland

contributor: van den Heuvel, Michael (Thesis advisor)

contributor: van den Heuvel, Michael (Supervisory Committee Member)

contributor: Vodden, Kelly (Supervisory Committee Member)

contributor: Baldacchino, Godfrey (Supervisory Committee Member)

contributor: Mitchell, Jean (Supervisory Committee Member)

contributor: van den Heuvel, Michael (Examination Committee Member)

contributor: Vodden, Kelly (Examination Committee Member)

contributor: Baldacchino, Godfrey (Examination Committee Member)

contributor: Mitchell, Jean (Examination Committee Member)

contributor: Foley, Paul (Examination Committee Member)

format: electronic 176 application/pdf PUBLISHED

abstract:
This thesis examines the relationship between fisheries policy, fisheries management, and island community development in Maine and Newfoundland. Three research questions and themes guided this work: 1) what kind of relationship there is between island community development, fisheries policy, and fisheries management; 2) how communities responded to changes in the fishery; and 3) how each community’s location influenced the ability of each community to respond to changes. Five island communities, Anchor Point and Fogo Island/Change Islands in Newfoundland, and Chebeague Island, Monhegan, and Swan’s Island in Maine, were used as case studies and semi-structured interviews were conducted with people involved in fisheries and community development in each community in order to answer these questions.
Two particular aspects of fisheries policy and fisheries management were explored based upon observed trends from interviews: methods of limiting catch and licensing systems in each region. These themes connect to each other and relate to access to the resource. Each community had concerns about the ability of current and future harvesters and lobstermen to have economically viable access to the resource. In Newfoundland the relationship between island community development, fisheries policy, and fisheries management was perceived to be a top-down relationship; whereas in Maine it was perceived to be more integrated. Two of the most prevalent ways that communities directly responded to fisheries policy and fisheries management were either by changing management for their region or by creating new selling and processing capacity for their product. Typically the impacts felt in communities were from the cumulative nature of policy decisions. Respondents from each community felt that their location on an island was influential to their ability to respond to changes in the fisheries that they are dependent upon. Island community development, fisheries management, and fisheries policy have a complex relationship; this thesis explores those nuances.


title: The synthesis, characterization, and analysis of polynorbornenes containing various organometallic species

contributor: Abd-El-Aziz, Alaa (Supervisory Committee Member)

contributor: Etkin, Nola (Supervisory Committee Member)

contributor: Abd-El-Aziz, Alaa (Examination Committee Member)

contributor: Etkin, Nola (Examination Committee Member)

contributor: Wagner, Brian (Examination Committee Member)

contributor: Bissessur, Rabin (Examination Committee Member)

contributor: Carragher, Charles (Examination Committee Member)

contributor: Kerr, Russell (Examination Committee Member)

contributor: Wagner, Brian (Supervisory Committee Member)

contributor: Bissessur, Rabin (Supervisory Committee Member)

format: electronic 204 application/pdf PUBLISHED

rights:
In presenting this thesis in partial fulfillment of the requirements for a postgraduate
degree from the University of Prince Edward Island, I agree that the Libraries of this
University may make this thesis freely available for inspection and give
permission to add an electronic version of the thesis to the Digital Repository at the
University of Prince Edward Island. Moreover the author agrees that permission for
extensive copying of this thesis for scholarly purposes may be granted by the professor or
professors who supervised my thesis work, or, in their absence, by the Chair of the
Department or the Dean of the Faculty in which my thesis work was done. It is
understood any copying or publication or use of this thesis or parts thereof for financial
gain shall not be allowed without my written permission. It is also understood that due
recognition shall be given to me and to the University of Prince Edward Island in any
scholarly use which may be made of any material in my thesis.

abstract:
This thesis describes the synthetic strategies for the incorporation of a number of metal
species into a series of polynorbornenes, as well as their characterization and thermal
analysis. This was accomplished through the synthesis of new monometallic norbornene
compounds containing chromium and iron, which was either neutral or cationic, as well
as new bimetallic norbornenes containing chromium and cobalt in addition to neutral iron.
A series of polymers were developed using Grubbs' 2nd generation catalyst and
their thermal properties determined. From there, these properties were compared to a
series of copolymers and block copolymers, which were synthesized using the same
norbornene structure that was utilized for the homopolymers. All compounds and
polymers were characterized utilizing a combination of 1H NMR, 13C NMR, several two
dimensional NMR techniques, solid state NMR, and scanning electron microscopy. The
molecular weight of the polymer synthesised in Chapter Four was determined through
GPC, which was not possible for the other polymers due to insolubility. Thermal
properties were determined through TGA and DSC. Further work in this area would
include conversion of these materials into ceramics and a series of mechanical,
conductive, and magnetic tests on both the polymers and the ceramics formed.
Additional work would also explore varying the ratio of metals in the copolymers, as well
as introducing other metals into the materials.


title: Examining climate change & irrigation requirements on James Island, British Columbia

contributor: Fenech, Adam (Supervisory Committee Member)

contributor: Brinklow, Laurie (Supervisory Committee Member)

contributor: Randall, James (Supervisory Committee Member)

contributor: Fenech, Adam (Examination Committee Member)

contributor: Brinklow, Laurie (Examination Committee Member)

contributor: Randall, James (Examination Committee Member)

contributor: Catto, Norm (Examination Committee Member)

format: electronic 110 application/pdf PUBLISHED

abstract:
As the Earth’s climate continues to change, so too does the availability of
freshwater resources. Small islands are at the forefront of freshwater vulnerability
and therefore must be ready to adapt. In order to implement effective adaptation
measures, accurate projections of future water use are required. This study
examines the climate and water use of James Island, British Columbia, during the
five-year period 2009–2013. Potential future climate scenarios for James Island,
created using the guidelines set forth by the United Nations Intergovernmental
Panel on Climate Change 5th Assessment Report are also examined. The future
climate projections, along with the climate and irrigation data, are utilized to create
a new method for estimating potential future irrigation requirements based on
irrigation flow per growing degree-days. Future increase in annual mean
temperature of 0.9°C for the 2020s, 1.9°C in the 2050s and 2.8°C in the 2080s
suggest an increase in irrigation requirements of 17% in the 2020s, 38.5% in the
2050s and 59% in the 2080s. In conclusion, the merits of alternative irrigation
strategies such as water reclamation and desalination are discussed, as well as
their potential application for James Island.


title: Identité dans l'interstice: Une enquête narrative auprès d'élèves anglo-dominants d'héritage francophone qui fréquentent l'école de langue française à l'Île-du-Prince-Édouard

contributor:
Gauthier, Rachelle (author)
(Thesis advisor)
(Supervisory Committee Member)
(Examination Committee Member)

format: electronic application/pdf


title: Negotiating two worlds: The voices of young Island Acadians


title: Hybrid Sol-Gel Poly(N-Ethylaniline) coatings with microcapsules with increased self-healing properties

contributor: Abd-El-Aziz, Alaa (Supervisory Committee Member)

contributor: Hsiao, Amy (Supervisory Committee Member)

contributor: Rodgers, Marianne (Supervisory Committee Member)

contributor: Hsiao, Amy (Examination Committee Member)

contributor: Rodgers, Marianne (Examination Committee Member)

contributor: VomBraucke, Troy (Examination Committee Member)

contributor: Ross, Joel (Examination Committee Member)

format: electronic 139 application/pdf

abstract:
Hybrid sol-gel coatings have the ability to actively replace hexavalent chromium compounds that are commonly used for aircraft coatings. Sol-gel coatings alone have become a large research topic due to their ability to be very corrosion resistant, but many are too brittle to be used as coatings in the aerospace industry. By combining a sol-gel compound with a conductive organic polymer, the resulting coating has a higher flexibility and a higher corrosion resistant ability. Combining the hybrid sol-gel coating with microcapsules filled with poly(dimethylsiloxane), the corrosion resistance of the protected substrate is increased. The coatings and microcapsules were characterized using FTIR, NMR, SEM and TGA.
Three coatings were exposed to three different environmental conditions. A hybrid poly(N-ethylaniline) sol-gel coating with microcapsules, and sol-gel with microcapsules and a hybrid sol-gel coating were subjected over 28 days to a salt-spray chamber at room temperature and varied temperature testing varying between 5 and 50°C. The chambers followed the ASTM B117 standard for operating a salt spray apparatus. Additional testing was completed on the effect of humidity on coating integrity using ASTM D2247 standard for testing water resistance of coatings in 100% humidity. By monitoring the corrosion of the samples using EIS and SEM, the coatings with microcapsules showed an increase in corrosion resistance once during the 28 days, while the hybrid sol-gel coating showed steady degradation.


title: A comprehensive analysis of the microbial diversity associated with Eunicea fusca and related Plexauridae octocorals, and the isolation of new natural products from selected, associated bacteria

contributor: Kerr, Russell (Supervisory Committee Member)

contributor: Burka, John (Supervisory Committee Member)

contributor: Lewis, Jeff (Supervisory Committee Member)

contributor: Van Den Heuvel, Michael (Supervisory Committee Member)

contributor: Chapman, Bob (Supervisory Committee Member)

contributor: Bate, Luis (Examination Committee Member)

contributor: Kerr, Russell (Examination Committee Member)

contributor: McCarthy, Peter (Examination Committee Member)

contributor: Lewis, Jeff (Examination Committee Member)

contributor: Martin, Chelsea (Examination Committee Member)

format: electronic 307 application/pdf PUBLISHED

rights:
In presenting this thesis in partial fulfillment of the requirements for a postgraduate
degree from the University of Prince Edward Island, I agree that the Libraries of this University
may make it freely available for inspection. I further agree that permission for extensive copying
of this thesis for scholarly purposes may be granted by the professor or professors who supervised
my thesis work, or, in their absence, by the Chair of the Department or the Dean of the Faculty in
which my thesis work was done. it is understood any copying or publication or use of this thesis
or parts thereof for financial gain shall not be allowed without my written permission. It is also
understood that due recognition shall be given to me and to the University of Prince Edward
Island in any scholarly use which may be made of any material in my thesis.

abstract:
Marine invertebrates, including octocorals, are a prolific source of marine natural products (MNPs) and are also known to host diverse microbial communities. It is well-established that marine microbes are producers of bioactive secondary metabolites. Accordingly, it is hypothesized that bioactive metabolites extracted from some marine invertebrates may actually be produced by associated microbes rather than the invertebrate host. This research aimed to characterize the microbial community of E. fusca and related Plexauridae octocorals and to discover novel, bioactive compounds biosynthesized by associated microorganisms. E. fusca was the main focus of this study because its microbial community has not been thoroughly characterized, and it is the sole source of the potent anti-inflammatory diterpenes fuscol, eunicol, and the fuscosides. Investigations of the unexplored E. fusca microbial
community could therefore lead to the discovery of novel MNPs from unexplored microbes, as well as provide insights into the biosynthetic source of these diterpenes. The microbiome of Floridian and Bahamian E. fusca and related Plexauridae octocorals collected in June 2009 were characterized using culture-independent (454-pyrosequencing, denaturing gradient gel electrophoresis, cloning, and species-specific primers) and -dependent (dilution plating) methods. The culture-independent analysis revealed that E. fusca hosted a geographically-heterogeneous bacterial community, where Endozoicomonas relatives dominated the Florida sites, and Mycoplasma relatives dominated at The Bahamas sites. There were, however, a few stable bacterial associates found in all E. fusca at all sites, including relatives of the Endozoicomonas, Mycoplasma, and Oceanospirillales, suggesting that these bacteria may be
critical to holobiont functioning, and differences in environmental conditions at the locations may affect the dominant community member. E. fusca's bacterial community also differed from that of closely-related Plexauridae octocorals and the surrounding seawater. All octocorals contained the same clade of dinoflagellate, Symbiodinium B1/B184. However, the fungal and archaeal communities were not consistent between Plexauridae species or location. In the culture-dependent study, 137 unique bacteria and 11 unique fungi were cultured from the Plexauridae octocorals; 31 of the isolated bacteria were putative novel species based on 16S rDNA analysis (<97% sequence identity of 16S rDNA). Two of the novel species, Endozoicomonas euniceicola sp. nov. and Endozoicomonas gorgoniicola sp. nov., had nearly identical 16S rDNA sequences to the dominant members in the culture-independent bacterial community, providing the extraordinary opportunity to explore the biology and chemistry of these putative octocoral symbionts. These two bacteria were formally characterized, revealing that they were genotypically, phenotypically, and chemotypically different from the three Endozoicomonas spp. cultures previously isolated from other marine invertebrates. From the culture-dependent library, selected bacteria were fermented and analyzed for MNP production. Under the evaluated fermentation conditions, two bacteria were found to produce novel MNPs. A Labrenzia sp. produced a family of novel fatty acid derivatives, and a Euzebyella sp. produced a novel 2,5-dialkylresorcinol with good gram-positive bioactivity. In conclusion, Eunicea fusca hosts a geographically heterogeneous and diverse microbial community that differs from that of other closely-related Plexauridae octocorals and the surrounding environment. This microbial community has a varied metabolic repertoire, which can ultimately lead to the discovery of novel, microbial MNPs.


title: From Maine to Chiloé: the effects of social enterprises on marginalized experiences: a comparative study of Penobscot Bay Islands, Maine and Chiloe Islands, Chile

contributor: Novaczek, Irené (Supervisory Committee Member)

contributor: Novaczek, Irené (Examination Committee Member)

contributor: Stalker, L. Lynda Harling (Thesis advisor)

contributor: Stalker, L. Lynda Harling (Supervisory Committee Member)

contributor: Lapping, Mark (Supervisory Committee Member)

contributor: Stalker, L. Lynda Harling (Examination Committee Member)

contributor: Lapping, Mark (Examination Committee Member)

contributor: Brown, Leslie (Examination Committee Member)

format: electronic 282 application/pdf PUBLISHED

abstract:
Although the notion of islands contains a strong association or undertone of isolation and closure, islands are never closed environments. None the less, Islands are susceptible to exogenous factors and often exposed to development processes that can lead to inequality and inequity in society and space. Global change and the ongoing progression of globalization and processes of deregulation may deepen regional disparities and thus increase or position areas in a state of marginalization. Furthermore, on islands, while size itself matters in economic terms, topography and geographic location relative to major economic centers can also position them in a state of marginalization.
Over recent decades, some islands have experienced improvements in terms of their infrastructure, transportation and communication systems. Yet they still struggle with certain aspects such as the cost for daily operation of services, and the overall aspects of development and decision making processes that affect their day to day livelihoods. This research revealed a series of day to day challenges that people on remote islands face. A social enterprise (SE) is a distinctive form of entity that is rapidly gaining recognition from policy makers worldwide. The SEs are seen as unique entities that are changing relationships among those engaged in the market place, civil society and public institutions. They are able to do this through the pursuit of goals that go beyond mere profit acquisition. V
This study compares SEs located on islands in the Penobscot Bay, off the coast of Maine on the United States’ eastern sea board, and the Islands of Chiloé, off the southwest coast of Chile. This study of SEs offers an opportunity to understand people’s experiences with SEs and whether, how, and under what circumstances SEs affect the lives of those experiencing marginalization. Furthermore, it explores the effect on the level of inclusion of individuals within island society and their communities and how SEs aid their members in improving their quality of life.


title: Syndrome classification through a retrospective analysis of porcine submissions to a regional animal health laboratory

contributor: Hurnik, Dan (Supervisory Committee Member)

contributor: Revie, Crawford (Supervisory Committee Member)

contributor: Hanna, Paul (Supervisory Committee Member)

contributor: Dohoo, Ian (Supervisory Committee Member)

contributor: Sanchez, Javier (Supervisory Committee Member)

contributor: Burns, Jennifer (Examination Committee Member)

contributor: Revie, Crawford (Examination Committee Member)

contributor: Hanna, Paul (Examination Committee Member)

contributor: McClure, J. Trenton (Examination Committee Member)

contributor: Muckle, Ann (Examination Committee Member)

format: 164 application/pdf PUBLISHED electronic

abstract:
In response to the global threats of emerging infectious diseases and bioterrorism events, public health surveillance developed analytical methods to cluster early health indicators from multiple data sources into “syndromes” for rapid and efficient disease detection. Syndromic surveillance has become well established in public health, using many different health indicators from multiple sources. In animal health, the timeliness and efficiency of disease detection in early warning surveillance systems has been enhanced by including syndromic surveillance methods. Animal health syndromic surveillance improves disease detection through the analysis of pre-diagnostic data collected for other purposes, from sources such as laboratories, veterinary clinics, abattoirs, farms and pharmacies. However, the data are inherently non-disease specific compared to traditional surveillance and require analyses to ensure that syndromes represent significant diseases as accurately as possible. Syndrome classification is an analytical process that identifies, collates and validates pre-diagnostic indicators within a data source into accurate and viable syndromes.
The goals of this thesis were as follows: a) Review surveillance systems and methods to understand the scale, complexity and validity of different syndromic surveillance approaches. b) Describe and evaluate six years of swine laboratory submission data to Veterinary Diagnostic Services (VDS) in the province of Manitoba, Canada, for the purpose of syndromic surveillance. c) Finally, identify and validate the most appropriate syndromes from pre-diagnostic data within the submitted swine cases.
An initial systematic review of public health syndromic surveillance was conducted with 81 studies meeting the criteria. The variety and frequency of populations under surveillance, information sources, pre-diagnostic indicators, syndromes and reported values were recorded. The predominant methods for syndrome classification, temporal and spatial analysis and aberration detection were also described.
21,665 swine laboratory submissions from January 2003 to March 2009, including 4726 pathology cases, were evaluated. The frequency and distributions of the predominant pre-diagnostic indicators, test requests and specimen types, were described. The most common pathology diagnoses and organ system involvement were reported for the pathology submissions. For syndrome validation, a Multiple Correspondence Analysis was conducted to cluster multiple pathology diagnoses per case into four diagnostic groups based on organ systems; Respiratory, Multisystemic, Gastrointestinal and “Other”.
Syndrome classification was completed, first using agglomerative hierarchical clustering to classify syndromes from 30 test requests and 34 specimen types. For validation, the syndromes were used as predictive variables in a multinomial logistic regression model applied to training and test data sets. The overall model sensitivity, specificity and predictive values for each organ system outcome were estimated. The individual syndromes were compared using relative risk ratios and marginal effects. Five syndromes were identified as having a significantly higher predictive association with one organ system group (compared to the other three): Respiratory, GI, Reproductive, Joint and PCV (specific to porcine circovirus associated disease).
The methods in this thesis identified a simplified analytical approach for syndrome classification of laboratory test requests and specimen types within swine submissions. Alternative algorithms for syndrome grouping, establishment of temporal baselines and exploration of automated aberration detection were identified as areas for future research.


title: Scholarship in abundance: Influence, engagement, and attention in scholarly networks

contributor: McAuley, Sandy (Supervisory Committee Member)

contributor: Krautwurst, Udo (Supervisory Committee Member)

contributor: Couros, Alec (Supervisory Committee Member)

contributor: McAuley, Sandy (Examination Committee Member)

contributor: Krautwurst, Udo (Examination Committee Member)

contributor: Couros, Alec (Examination Committee Member)

contributor: MacKinnon, Stacey (Examination Committee Member)

contributor: Weller, Martin (Examination Committee Member)

format: electronic 158 application/pdf PUBLISHED

abstract:
In an era of knowledge abundance, scholars have the capacity to distribute and share ideas
and artifacts via digital networks, yet networked scholarly engagement often remains
unrecognized within institutional spheres of influence. The purpose of this dissertation study
is to explore the meanings constructed and enacted within the networked practices of 13
scholars actively engaged in both institutional and networked participatory scholarship.
Using ethnographic methods including participant observation, interviews, and document
analysis, the study investigates networks as sites of scholarship, with the intent of furthering
institutional academia’s understanding of networked practices. The three papers that make up
the dissertation each articulate a specific thread of intersection between institutional and
networked scholarship: the first focuses on what counts as academic influence within
networked circles, the second on networks’ terms of value and reward, and the third on the
relationships between attention, care, and vulnerability in scholarly networks. Together, the
papers conclude that networked scholarly practices of engagement align broadly with those
of academia, yet enable and demand scholars’ individual cultivation of influence, visibility,
and audiences. Thus networked scholarship rewards connection, collaboration, and curation
between individuals rather than roles or institutions, fostering cross-disciplinary and public
engagement and a bridging of the personal/professional divide. The study contributes to
knowledge by situating networked scholarly practices within the scholarly tradition, while
articulating the terms on which knowledge abundance and networked practices open up new
spheres of opportunity and vulnerability for scholars.


title: Discovery of novel molecular immune mediators in the American lobster (Homarus americanus) during bacterial, eukaryotic parasitic and viral challenges

contributor: Kibenge, Frederick (Supervisory Committee Member)

contributor: Greenwood, Spencer (Supervisory Committee Member)

contributor: Byrne, Philip (Supervisory Committee Member)

contributor: Davidson, Jeff (Supervisory Committee Member)

contributor: Fast, Mark (Supervisory Committee Member)

contributor: Wang, Yingwei (Supervisory Committee Member)

contributor: Whyte, Shona (Examination Committee Member)

contributor: Byrne, Philip (Examination Committee Member)

contributor: Greenwood, Spencer (Examination Committee Member)

contributor: Markham, Fred (Examination Committee Member)

contributor: Hauton, Chris (Examination Committee Member)

format: electronic 196 application/pdf PUBLISHED

abstract: The American lobster (Homarus americanus) is the most economically significant commercial fishery species in Canada. The Canadian lobster fishery provides tens of thousands of jobs, and is the economic driver of hundreds of rural communities in Atlantic Canada and Quebec. The adult lobster is susceptible to relatively few pathogens but very little is known about how its immune system is capable of mediating this pathogen resistance. Additionally, there is no definitive clinical biomarker that is capable of assessing overall lobster health, something that would be valuable to a fishery where lobsters are the most lucrative when they are sold as a live product. The purpose of this project was to discover how the H. americanus humoral immune system responds to bacterial, eukaryotic parasitic and viral pathogens. This was performed by using high-throughput transcriptomics, in the form of microarray gene-expression analysis, to monitor the expression of classical immune molecules, as well as discover novel immune mediators. This project discovered hundreds of new H. americanus genes that have not previously been associated with either lobster or crustacean immunity. The expression of these novel immune-related genes is especially interesting because over half of them have no similarity to proteins in GenBank, little if any functional characterization, and pathogen class-specific expression. The conventional immune paradigm for any crustacean innate immune response is that it is non-specific and responds similarly to all microorganisms, pathogenic or not. These studies have determined that this is not the case. There is consistent and unique differential expression of genes for each of the pathogen classes examined, and even differential expression of isoforms within gene families that is pathogen dependent. Among the most interesting genes that have been discovered are the six isoforms of anti-lipopolysaccharide factor family (ALFHa-1, ALFHa-2, ALFHa-3, ALFHa-4, ALFHa-6 and ALFHa-7), acute phase serum amyloid protein A (SAA) and trypsin 1b. Four ALFHa family isoforms are differentially expressed during bacterial, Aerococcus viridans var. homari, and parasitic, Anophryoides haemophila, infections, where the differential expression of ALFHa-4 and ALFHa-2 isoforms are the most significant during bacterial and parasitic infections respectively. However, none of the six ALFHa genes are differentially expressed during viral, White Spot Syndrome Virus, infection. SAA is important because its expression is significantly increased in moribund lobsters during bacterial and parasitic infections, although not in viral infections. The protein sequence of SAA is highly conserved between humans and H. americanus suggesting the conservation of an important biological function such as innate immune activation. Trypsin 1b is the only gene that was differentially expressed during all three pathogen challenges. It is unclear what immunological role this gene plays in lobster or crustacean immunity but it is likely pivotal to immune activation, and a promising lobster health biomarker. These findings have made significant advances to our understanding of lobster immunity which can be applied to crustacean immunology as a whole. The lobster immune response can no longer be thought of a generalized non-specific response, but as one tailored to the invading pathogen.


title: School nutrition policy adherence and weight status in elementary school children in Prince Edward Island

contributor: Taylor, Jennifer (Supervisory Committee Member)

contributor: Taylor, Jennifer (Examination Committee Member)

contributor: MacLellan, Deborah (Examination Committee Member)

contributor: MacLellan, Deborah (Supervisory Committee Member)

format: electronic 86 application/pdf PUBLISHED

rights:
In presenting this thesis in partial fulfilment of the requirements for a graduate degree from the
University of Prince Edward Island, the author has agreed that the Robertson Library, University
of Prince Edward Island, may make this thesis freely available for inspection and gives
permission to add an electronic version of the thesis to the Digital Repository at the University of
Prince Edward Island. Moreover the author further agrees that permission for extensive copying
of this thesis for scholarly purposes may be granted by the professor or professors who
supervised the author’s thesis work, or, in their absence, by the Chair of the Department or the
Dean of the Faculty in which the author’s thesis work was done. It is understood that any
copying or publication or use of this thesis or parts thereof for financial gain shall not be allowed
without the author’s written permission. It is also understood that due recognition shall be given
to the author and to the University of Prince Edward Island in any scholarly use which may be
made of any material in the author’s thesis.

abstract:
The majority of Canadian provinces have adopted school nutrition
policies (SNP) in an effort to improve children‟s eating habits and reduce
childhood overweight and obesity. While a number of provinces have
implemented SNPs, there has been little in terms of evaluation across the
country. All elementary schools in Prince Edward Island (PEI) adopted a SNP in
2005-2006. The purpose of this study was to describe the changes in SNP
adherence over time, as well as assess the impact that SNP adherence has on
children‟s overweight and obesity rates. A self-administered survey was
distributed to all elementary school principals in 2007 and 2010. The Principal
School Food Survey (Appendix A) consisted of both a subjective and more
objective component to assess the level of implementation of all SNP elements.
The perceived adherence score was calculated using the responses from 15
subjective questions. Food list adherence, the more objective measure of
adherence, was assessed by comparing the reported food and beverage items sold
at lunch, in vending machines and canteens to policy guidelines. The relationship
between overweight and obesity rates and both measures of adherence was
assessed for 2010 only. It was predicted that schools with a higher level of
adherence would have lower rates of overweight and obesity. Non-parametric
tests (Wilcoxon rank sum, chi-square and Spearman‟s rho) were used to assess
changes in perceived adherence, food list adherence and the agreement between
food list and perceived adherence respectively. Logistic regression was used to
assess the impact that the level of policy adherence had on overweight and
obesity rates.
Results indicated that perceived adherence was higher in 2010 than 2007
(Mann-Whitney U= 519.5, p =0.007). Food list adherence for lunch program
items and canteen items decreased significantly from 2007 to 2010 (x2= 12.576,
df=3, p=0.006) while vending machines item adherence increased slightly during
the same time period (x2=13.689, df=1, p=0.008). There was no significant
agreement between overall perceived adherence scores and food list adherence;
however, a few policy elements (pricing foods to encourage healthy
consumption, promote healthy advertising, serve foods from „most often‟ or
„sometimes‟ list) did reveal a positive relationship with 2007 food list adherence.
There was some support for the hypothesis for the overweight model, in that
closer policy adherence (% allowed foods) was associated with lower overweight
rates in elementary school children. The study also found that schools with
higher perceived adherence scores had increased rates of overweight among
grade 5 and 6 children. The level of adherence was not, however, a significant
predictor of obesity rates. These findings are consistent with previous research
demonstrating the impact of SNP adherence on overweight rates but not obesity.
This study also found that physical activity, breakfast consumption, low-nutrient
density food (LNDF) consumption, student sex and parental education were
significant predictors of both overweight and obesity; in addition to these factors,
parental income and television frequency were also predictors of obesity. The
relationships between the co-variates and overweight and obesity were in the
3
expected direction. While the adoption of a SNP can be a positive first step to
change the school food environment, promote healthy eating habits and reduce
overweight among children, more comprehensive evaluation methods (ie.
objectively assessing adherence to all policy elements as opposed to just
available food and beverage items) are needed to identify potential barriers to
implementation and accurately assess the impact of such policy interventions.


title:
Evaluation of
serum biomarkers of collagen turnover in cats with hypertrophic cardiomyopathy

contributor: Côté, Etienne (Supervisory Committee Member)

contributor: Ihle, Sherri (Supervisory Committee Member)

contributor: Burton, Shelley (Supervisory Committee Member)

contributor: Gelens, Hans (Supervisory Committee Member)

contributor: Martinson, Shannon (Supervisory Committee Member)

contributor: Saleh, Tarek (Supervisory Committee Member)

contributor: Côté, Etienne (Examination Committee Member)

contributor: Saleh, Tarek (Examination Committee Member)

contributor: McConkey, Sandra (Examination Committee Member)

contributor: Matthews, Andrea (Examination Committee Member)

contributor: Foley, Peter (Examination Committee Member)

format: electronic 91 application/pdf PUBLISHED

rights:
In presenting this thesis in partial fulfillment of the requirements for a
postgraduate degree from the University of Prince Edward Island, I agree that the
Libraries of this University may make it freely available for inspection. I further
agree that permission for extensive copying of this thesis for scholarly purposes
may be granted by the professor or professors who supervised my thesis work, or,
in their absence, by the Chair of the Department or the Dean of the Faculty in
which my thesis work was done. It is understood any copying or publication or
use of this thesis or parts thereof for financial gain shall not be allowed without
my written permission. It is also understood that due recognition shall be given to
me and to the University of Prince Edward Island in any scholarly use which may
be made of any material in my thesis.

abstract:
BACKGROUND Myocardial fibrosis is a hallmark of hypertrophic
cardiomyopathy (HCM). Human patients with HCM have high serum
concentrations of biomarkers of collagen synthesis, indicating a profibrotic state.
This abnormality exists in sarcomere mutation carriers both with and without
overt left ventricular hypertrophy, suggesting its potential use in early
identification of HCM. Whether serum levels of biomarkers of collagen synthesis
are increased in cats with HCM is unknown.
HYPOTHESIS: We hypothesized that serum biomarkers of collagen turnover
could be measured in cats using commercially available enzyme-linked
immunosorbent assays (ELISAs), that cats with HCM would have higher serum
concentrations of a collagen synthesis biomarker than normal cats, and that a
collagen degradation biomarker would not differ between cats with HCM and
normal cats.
METHODS Cats presenting to a university veterinary cardiology referral service
were prospectively evaluated and enrolled in the study when they had an
echocardiographic diagnosis of HCM or no structural heart disease. Cats with a
high serum thyroid hormone (T4) concentration, high systolic arterial blood
pressure, recent or ongoing diuretic administration, echocardiographic diagnosis
of cardiomyopathies other than HCM or of other congenital or acquired lesions,
and/or overt signs of hypovolemia, were excluded. The diagnosis of HCM was
based on echocardiographic measurements of the interventricular septum (IVS)
and/or left ventricular free wall (LVFW) >5.5 mm in thickness. Cats with IVS and
LVFW <5.5 mm and no other echocardiographic abnormalities were considered
normal. Serum concentrations of C-terminal propeptide of type I procollagen
(PICP, marker of collagen synthesis) were attempted to be evaluated using 2
commercially available ELISAs. One was previously validated for use in humans
(Microvue™ EIA kit; Quidel®) and one in rats [ELISA kit for procollagen type I
C-terminal propeptide (PICP); Uscn Life Science Inc.] A commercially available
ELISA previously validated for use in cats (Serum CrossLaps® ELISA; Nordic
Bioscience Diagnostics) was used to quantify serum concentrations of C-terminal
telopeptide of type I collagen (CTx) as a marker of collagen degradation. We
compared serum [CTx] of cats with HCM and controls.
RESULTS Forty-seven cats qualified for and participated in the study: 28 with
an echocardiographic diagnosis of HCM and 19 normal controls. Serum samples
from 12 additional cats with unknown echocardiographic statuses were also used
in assay evaluation. In 22 experiments (8 for PICP using 1 ELISA, 10 for PICP
using a second ELISA, and 4 for CTx) conducted on a total of 114 blood samples
from 59 cats and 4 rats, stability, precision and linearity testing failed to provide
reliable results for quantifying serum [PICP] using either ELISA. There was no
difference in serum [CTx] between cats with HCM and normal controls (HCM:
mean 0.248 ng/ml; controls: mean 0.253 ng/ml; p=0.4).
CONCLUSIONS The 2 ELISAs evaluated are not valid for quantifying serum
[PICP] in the cat; therefore, we are unable to conclude whether or not serum
biomarkers reflect increased collagen synthesis in the pathophysiology of HCM in
cats. There was no evidence of enhanced collagen degradation in cats with HCM
compared to normal controls.


title: Development and validation of multiplex polymerase chain reaction based diagnostic procedures for detecting eight viruses and one viroid in the Potato Nuclear Stock Certification Program

contributor: Rodriguez, Juan (Supervisory Committee Member)

contributor: Martin, Chelsea (Examination Committee Member)

contributor: Xu, Huimin (Examination Committee Member)

contributor: Wang, Yingwei (Examination Committee Member)

contributor: Hale, Larry (Examination Committee Member)

contributor: Riveroll, Angela (Examination Committee Member)

contributor: Hale, Lawrence (Supervisory Committee Member)

contributor: Wang, Yingwei (Supervisory Committee Member)

format: electronic 222 application/pdf

abstract:
The Canadian Food Inspection Agency implements the Nuclear Stock Certification Program to ensure the production of high-quality and disease-free seed potatoes. Currently, this program employs double and triple antibody sandwich enzyme-linked immunosorbent assays (DAS- or TAS-ELISA) and return-polyacrylamide gel electrophoresis (R-PAGE) for detecting the targeted viruses and PSTVd (Potato spindle tuber viroid), respectively. Pathogen-specific antibodies for ELISA are commercially available for detecting PVM (Potato virus M), PMTV (Potato mop-top virus), PotLV (Potato latent virus), PLRV (Potato leafroll virus), PVY (Potato virus Y), PVS (Potato virus S), PVA (Potato virus A), and PVX (Potato virus X). However, the aforementioned methods are highly labour-intensive and time-consuming procedures with low sensitivity that require large sample inputs for screening. Moreover, both methods are involved with extensive experimental procedures and only allow for the screening of one pathogen each time, which further prolongs and complicates the overall diagnosing process.
In this study, multiplex PCR-based procedures were developed and validated to index the potato nuclear stock materials simultaneously in a qualitative way (“positive” or “negative”). Two mxRT-PCR (multiplex RT-PCR) and three mxRT-qPCR (multiplex real-time quantitative RT-PCR) procedures were developed for primary screening and confirmatory testing of all targeted pathogens under this program, respectively. As little as 1.0 μl of tissue sap from a microplant (in vitro plantlet) or 1.0 pg of total RNA extract was sufficient for reliable RT-PCR detection. Additionally, virus-specific RNA could be detected in RNA extracts with almost no non-specific amplification in the presence of other viral RNAs. The use of potato genome-specific primer set as an internal control provided a reference for assessing the quality of the RNA extracts and the amplification of the targeted RNAs. Furthermore, the genomes of virus and viroid isolates or strains used in this research were verified using the next-generation sequencing (NGS) technology to ensure the accuracy of the RT-PCR primers employed. All tests conducted using the mxRT-PCR and mxRT-qPCR procedures were validated using another diagnostic assay and known/unknown microplants.
Overall, the developed and validated standard multiplex PCR-based procedures in this study profoundly improved the sensitivity, specificity, efficiency, and feasibility with reductions in time and labour expenses for routine diagnostic testing of the nine targeted pathogens under the Nuclear Stock Certification Program compared to that of the currently employed ELISA and R-PAGE methods. Subsequently, the multiplex RCR-based procedures involved in this study are ready for implementation into the Nuclear Stock Certification Program. With the accurate and reliable diagnostic results generated by the multiplex PCR-based procedures, CFIA’s reputation and credibility for certifying potato nuclear stock materials will be further enhanced. Ultimately, this study promotes the trade of potato nuclear stock materials and collaboration between CFIA and the potato industries.