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Parasite species co-occurrence patterns on Peromyscus: Joint species distribution modelling
No full textIJP: Parasites and Wildlife 12 (2020) 199–206Hosts are often infested by multiple parasite species, but it is often unclear whether patterns of parasite co- occurrence are driven by parasite habitat requirements or parasite species interactions. Using data on infestation patterns of ectoparasitic arthropods (fleas, trombiculid mites, cuterebrid botflies) from deer mice (Peromyscus maniculatus), we analyzed species associations using joint species distribution modelling. We also experimentally removed a flea (Orchopeas leucopus) from a subset of deer mice to examine the effect on other common ecto- parasite species. We found that the mite (Neotrombicula microti) and botfly (Cuterebra sp.) had a negative re- lationship that is likely a true biotic species interaction. The flea had a negative association with the mite and a positive association with the botfly species, both of which appeared to be influenced by host traits or parasite life-history traits. Furthermore, experimental removal of the flea did not have a significant effect on ectoparasite prevalence of another species. Overall, these findings suggest that complex parasite species associations can be present among multiple parasite taxa, and that aggregation is not always the rule for ectoparasite communities of small mammals
“Everyone needs a purpose”: Service provider perspectives on young adults in long-term care in Northern Ontario
Get PDFThe purpose of this qualitative study was to gain an understanding of the experience of
young adults with disabilities entering long-term care from the perspective of six long-term care
staff and community-based service providers in Northern Ontario. This study was approached
with a social constructionist and critical social theory of disability worldview. This study sought
to understand the implications associated with young adults residing in long-term care homes in
Northern Ontario and to gain a better understanding of what the most appropriate housing
options are for this population. A number of themes emerged including, inadequate community-
based services, complex health and social needs, need for integrating health and social care, and proposed solutions. These themes point to a fragmented health care system that denies young
adults with disabilities the right to choose where they wish to live and receive care. Contributing
factors such as limited staffing, lack of training and environmental barriers minimize the
opportunity for these individuals’ to live dignified lives while residing in long-term care homes.
Findings from this study help identify policy planning needs for this population, from a Northern
perspective. A number of recommendations are proposed including the creation of specialized units within the long-term care, increased staffing levels with specialized training, and
collaboration of community partners for capacity building purposes. The recommendations also
identify the need for a continuum of housing options to be available for young adults with
disabilities and emphasizes the need for a province wide strategy for integrating health and social care.Master of Social Wor
Impairment in mitochondrial oxidative phosphorylation alters clock gene expression
Get PDFEpidemiological studies provide evidence that workers who perform chronic night shift work are
at significantly higher risk of a number of severe disease states including cancer. The perturbed
activity/rest and feeding/fasting cycles, which occurs in persons performing shift work or who
are subjected to jet lag, disrupt our normal 24- hour internal clock or circadian rhythm. The
molecular mechanisms that link chronic circadian disruption to disease are not well understood.
Since light exposure at night is known to decrease melatonin levels, some researchers have
hypothesized that a reduction in the nocturnal levels of this pineal hormone predisposes
individuals to disease. Animals that displayed atypical behaviours in their daily cycles, led to the
identification of eight-key clock or circadian genes that are differentially expressed during the
day and which determine normal internal timing. The expression of these genes was abnormal in
a large number of human tumors including breast cancer. In this study, a temperature shift
model was characterized and used as a means to synchronize the expression of these clock genes
in a human breast cancer cell line. The model was compared to another cell synchronization
protocol which utilizes serum shock and which showed differences in gene expression and cell
cycle regulation between the two protocols. The temperature shift model was then used to study
the impact of melatonin on clock gene expression and on the production of reactive oxygen
species (ROS) in cells exposed to chemotherapeutic drugs. Melatonin influenced the cell cycle
but did not cause significant differences in clock gene expression. Chemotherapeutic drugs
differed in their effects on the production of intracellular ROS. A mitochondrial deficient (Rhø)
cell line which exhibited impaired oxidative phosphorylation, was developed from MCF-7 cells.
The profile of clock gene expression in Rhø cells that were also subjected to the temperature shift
protocol was different than that of the parental MCF-7 line. This suggests that impairment of
mitochondrial function disrupts clock gene expression and may be a link to the oncogenic
transformation of cells
Canadian wildfires: a spatial-temporal assessment of fire activity and cause (1988 to 2018)
Get PDFVegetation zones such as the boreal forest in Canada have been shaped and maintained by
naturally occurring wildfires for centuries. However, as global climates have warmed due to an
increase in greenhouse gases within the atmosphere, there has been a profound impact on
Canada’s forests. As fire activity continues to be very influential in altering forest biomes in
Canada, it is important to analyze and evaluate these changes. The focus of this study is on
assessing change in fire frequency, severity, and cause of fire disturbances in relation to where
people reside in Canada. The timeframe for this study is a 30-year span, 1988 to 2018. The
datasets utilized allowed for both temporal and spatial analysis of forest fires for each province
and territory in Canada. Datasets were analyzed, and maps were developed using ESRI’s
ArcMap GIS software. There has been an increase in both frequency and severity (in terms of
area size) of forest fires over these 30 years. The main cause of this upsurge in fire activity is
associated with lightning, but human accident fires have also steadily increased particular in
proximity to Canada’s ecumene (where most people live). Human prescribed fires have also
surged, especially in western Canada, as these deliberately set fires have become more necessary
in efforts to safeguard Canada’s forest resource and vulnerable populations. As the geography of
forest fire activity continues to evolve in Canada, this type of spatial-temporal research is useful
to those who develop new policies, mitigation plans, and adaptation strategies to protect the
vitality of forest ecosystems and the safety of Canadian populations4th year Geography Thesi
Semi-orthogonal non-negative factorization as a feature extraction method to improve prediction accuracy of microarray cancer data
No full textAbnormal growth in cells with the potential to diffuse to other parts of the human body could occur due
to multiple reasons such as changes in DNA segments activity. Altering DNA methylation is known as
an important factor in cancer development and altering DNA activity by avoiding some of the normal
activities of DNA. Feature selection and feature extraction is used to reduce the dimensionality in high
dimensional datasets as well as to filter the most useful features in predicting gene expression for a
cancer. A number of feature extraction methods have been used in literature for selecting the most useful
features. In this study Semi-orthogonal Non-Negative Factorization (SONMF) was studied and tested on
four microarray cancer datasets for feature extraction and compared with FFT features, Symmetry of
Methylation Density Features, Principal Component Analysis (PCA) and Non-negative Matrix
Factorization (NMF). Five different classifiers, namely Naïve Bayes, Support Vector Machine (SVM),
K-nearest Neighbour (KNN), Random Forest and Neural Network were used to predict the gene
expression of the four cancer microarray datasets. The experiments show that for colon cancer dataset,
Semi-orthogonal NMF (SONMF) and Non-negative Matrix Factorization (NMF) with Naïve Bayes
classifier performed the best compared with other feature extraction methods. It was shown by the oneway analysis of variance that the accuracy, specificity and sensitivity of SONMF was significantly higher
than PCA. However, in terms of the highest accuracy, SONMF and NMF feature extraction methods
give the best performance with Naïve Bayes classifier for Colon cancer dataset. For Oral cancer dataset,
the highest accuracy was observed with SONMF and Neural Network classifier. In Leukemia cancer, the
highest accuracy of 100% was observed with NMF, SONMF and PCA with Neural Network and SVM
classifiers. However, comparing the median for the best classifier shows that the median of the SONMF
and NMF were slightly higher than PCA. For prostate cancer dataset, SONMF with Naïve Bayes
classifier gave the highest accuracy. However, the classification accuracy was not significantly different from PCA and NMF. Overall, the results of SONMF were more consistent compared with other features
extraction methods
Adaptive reuse in a declining city: altering the Station Mall on the Sault Ste. Marie Waterfront
No full textThis Thesis takes a closer look at my hometown of Sault Ste. Marie, ON. I have found
that overall this industrial city has been in a decline or dying over the past decade or longer. The
differences when compared to the decline of other industrial cities is that the industry backbone
of Sault Ste. Marie is currently thriving. This decline is stressed by an aging community, lack
of available work, and continuous emigration of younger generations. This has led to a stagnant
economy, degradation of infrastructure, and rise of criminal culture throughout the city. Nowhere else
is this more evident than in the downtown core of Sault Ste. Marie Within this thesis, I look towards the efficient use of our existing built environment; focusing on adaptive reuse on multiple scales, from existing architectural structures to sites and reintroducing it to the social urban environment of the community. Taking this opportunity to research how to work with these spaces architecturally, programmatically and urbanistically, I am making the effort to effectively revitalize these declining rough areas or neighbourhoods. This topic stems from a
belief in the importance of taking a sustainable approach to an existing building’s embodied energy,
while also mitigating urban sprawl. Meanwhile, recognizing that the re-use of existing buildings or
spaces allows for the chance of preserving (rediscovering) history, emotion, and atmosphere while
introducing new programs to these spaces. The question that is explored within this thesis is whether the revitalization of a historical
centerpiece within a city that is in a state of decline can have enough of an impact to stabilize the
surrounding community. Throughout the growth of medium sized cities there develops a phenomenon
known as ‘doughnut cities’. This happens when a city continues to expand outwards and less focus
is placed on the center or downtown leading to the death or decline of said area. In addition to this,
there is also precedent for the death or decline of single industry cities. These cities tend to fall into
decline when the main industry takes a downturn; resulting in effects to job availability and the local
economy. Both of these phenomena look as though to play a part in the situation Sault Ste. Marie finds itself in currently. The proposed project looks at redesigning and reprogramming the Station Mall and Downtown Waterfront site in Sault Ste. Marie. Over the years, projects reprogramming existing
historical buildings have had positive impact on their surrounding sites and the community. Although,
the city’s downtown and predominantly this site has suffered a gradual abandonment and decline,
through this research project I believe a positive change can be made for the city and its community. This thesis explores these topics and questions through extensive research in addition to a methodology focusing on the use of mapping and layering to progress through the project. From historical mapping to current site analysis; working at multiple scales from city, to neighbourhoods, to the building. Taking a layered approach to fully understand the historical and situational basis within the project and transition into the final design proposition
The lake as a vessel for life: an architectural response to connecting leisure landscapes about the Muskoka Lakes
No full textExamining the anthropogenic change over the
last two hundred years, Canada’s landscape at large
has been molded into that of a globalized society.
Often by means of the infrastructure that connects
these economies, the people that drive them, drive
upon the roads and make use of these same modes
of transportation as well. The research will focus
on the necessity of providing alternative modes of
conveyance about the community at both the local
but also provincial scales. As means of connecting
urban civilizations become safer, faster and more
efficient, our own vision of space and time trend
towards that of a compressed reality[1]. A reality
whereby one place is just as readily accessible to the
average citizen as the next, as if distance and – with
any luck – the emissions that coincide with traversing
any given landscape are troubles of the past. Now, as we rely upon contemporary
technology more and more to provide an immediacy
of experience, that very experience estranges
perceptions of landscapes and places that are not of
their own corporeality[2]. Thus, the question is posed;
what subverted intentions do people’s metaphysical
preconceptions of one place, impose onto the next
when engaging in true corporeality? In a period in which transient and trans-local
lifestyles are colliding with those of domestic comfort
across numerous temporal and spatial agendas. How
then, do local populations perceive and interpret
the globalization of space brought upon by these
trans-local residents – daytime or seasonal – that
are more often imposed upon localities rather than
discussed? In a manner of collaboration rather than
apprehensive co-existence, can local, year-round
architectural programming begin to reimagine the
vernacular practices within a given context, provided
a history of translocality? Without affecting the landscapes that continue
to facilitate these exchanges of people, knowledge,
and economics amongst these different populations
in an adverse manner, but rather instill a context specific sense of year-round resiliency? How might the design of civic spaces within these inherently
trans-local destinations act as an inclusive space for
all to experience? Extrapolating from the brief yet thorough
history of Ontario’s cottage and lodging culture about
the Muskoka Lakes. Colonial-European settlement
has played a significant role in how the ethnography
of rural and urban Canadian lives at large, have
taken form – both in architectural and societal
manifestations. Inadvertently, the privatization of
lake-frontage within the Muskoka Lakes has been
a subject of historic subversion and contemporary
discussion since discovery. Still to this day, finding no
sustainable resolve. On a seasonal basis, the area has
become so saturated with an industry that depends
upon the influx of non-permanent residents, such that
it promotes exclusivity upon the lakes, as the further
privatization of lodging ensues. Both, as the translocal “cottage” and archetypal Muskokan “resort”
establish themselves as globalized commodity,
rather than corporeal experience. In examining the past, with contemporary and
historic modes of lodging upon the lakes acting as both
access and destination, how can the reinterpretation
of the architecture and social structuring of past
resorts provide a new paradigm to act as precedent
at larger scales, advocating for interconnected
communities and landscapes. In that the implicit
biases assumed by each of three populations – the
local, trans-local, and day-visitor – trend towards
solidarity and sustainability for all. The overt position
that this paper will take is that of the apprehensive
resident, concerned with the privatization of the
Muskoka Lakes so that generations to come may
transcend temporal constraint of travelling to and
from the area to enjoy the rejuvenating, embodied
experiences that this unique landscape provides
those who reside upon it
Characterizing the structural Influence of electromagnetic field application geometry on biological systems
No full textThere is growing literature that describes the effects that exposures to different forms of
magnetic and electromagnetic fields have on biological systems. Some robust effects have been
reported when the temporal structure of the electromagnetic field is patterned after what has
been observed biologically. However, there has been little effort devoted to ascertaining the
role for that physical application geometry, the structure through that current is presented, plays
in the bio-effectivity of patterned EMF. Here we devised a series of investigations that
compared 4 unique geometric organizations of copper wire based application devices to
generate patterned EMFs in order to discern if application geometry has any impact on
biological responses from cell systems treated with exposure to EMF. Furthermore, we
examined the structural pattern of a burst-firing EMF in order to characterize that parameters
are important in optimizing the proportion of cells that can be induced to bear plasma
membrane extensions in a cell model of induced neuritogenesis. Results of the experiments
conducted within this thesis show that the pattern of the EMF applied to PC-12 cells is the most
important factor to promote neurite outgrowth. Other parameters such as: the intensity of the
applied field, the timing of the field, exposure duration, and whether or not the pattern in
constantly or intermittently (i.e., rotated) exposed to PC-12 cells treated with forskolin do not
appreciably impact the growth of neurites. Investigations using different magnetic geometries
(e.g., structures around that copper wire is wound) were able to show that the physical structure
of the EMF-generating device contribute to the efficacy of neurogenesis of PC-12 cells exposed
to burst-firing pattern. Furthermore, unique EMF-generating devices influenced spectral
profiles of ultra-weak photons emitted from B16-BL6 cells. The differences obtained between
magnetic field generating devices suggest that the more heterogeneous the patterned EMF the
more impactful it is on the structural and functional aspects of the biological system under
investigation. Rigorous physical experimentation examining the features associated with unique structures around that copper wire is wound, showed that if the EMF-generating device
approaches the structure of a dome, it has the capacity to reduce background magnetic field
intensity and may provide insight (e.g., a mechanism) as to the efficaciousness of observed
effects when a patterned EMF is generated through this device
An investigation into the feasibility of improving the sustainability of a biogas fueled electricity generator by capturing CO2 exhaust emissions using photosynthetic green microalgae
No full textMunicipal solid waste landfills release a methane rich biogas, which can be combusted in standalone electricity generators. This work, which measured the exhausted off-gas from a biogas fed
generator, which at an average of 526˚C was 5,556 Nm3
/hour and contained 11% CO2. It is
hypothesized that this off-gas could be captured and used as a year-round carbon source for
photosynthetic microalgae. A pilot plant concept is modeled to be built at later date for a
feasibility CO2 capture study. The proposed pilot plant consists of ten 1 m3 tanks (1 seed tank, 3
sets of biological triplicates) and would take 0.34% of the total off-gas. The model produced
indicated that it could be operated above 15˚C and 30˚C year-round and has the potential to
produce 2.7 kg dry weight microalgae m-3 day-1 of lipid-rich microalgae for research and market analysis
purposes
Ixodid tick effects on deer mice (Peromyscus maniculatus) hematology and ectop
No full textThe ranges of the blacklegged tick (Ixodes scapularis) and the wood tick (Dermacentor
variabilis) are expanding northward in Ontario, Canada in response to climate warming, reaching
naïve or inexperienced host populations of deer mice (Peromyscus maniculatus) in more
northern areas. As hematophagous parasites, ticks can affect their host’s hematology and
differing levels of hemoglobin in mice populations where tick exposure varies, may be due to the
difference in exposure to ticks. If a naïve mouse population does not cohabitate with an
established tick population, the mice should then have higher hemoglobin levels since they are
not being affected by ticks. The parasite community structures of deer mouse hosts should also
differ when ticks are prevalent at varying exposure levels, as the prevalence of these ticks is
expected to decrease the likelihood of other ectoparasite species co-occurring with them on the
host. Blood samples were collected from individual mice from populations where: 1) both
blacklegged ticks and wood ticks were prevalent, 2) only wood ticks were prevalent, or 3) where
both tick species were absent in order to assess hemoglobin levels. Ectoparasites were collected
from these same mice to determine parasite loads and species co-occurrences. Both my
hypotheses were supported as hemoglobin levels were found to be higher in naïve mice
compared to infested mice, particularly those with high tick infestations, and heterospecific
parasite prevalence appeared to be higher when ticks were absent. As the ticks’ ranges expand, it
is important to understand the differences between naïve and experienced hosts when the
prevalence of these ticks can potentially alter the physiology and community assemblages of
naïve mice