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Online learning as a social environment — toward the refinement of practice
Get PDFThe 2020 publication of The Distance Learning Playbook implores us to “never let a
crisis go to waste” (Fisher et al., 2020, p. 169). This quote is applicable to the COVID-19
pandemic, a crisis from which we continue to learn. We continue to use lessons-learned
during the pandemic to refine practice while moving toward the future and the betterment of
teaching and learning. One lesson learned from the pandemic came from the transition to
online learning as a strategy for students who, for whatever reason, could not access
in-person learning. This transition toward online learning created a myriad of challenges for
instructors and students. These challenges included learning about and applying unfamiliar
technologies, grappling with a sense of aloneness when social distancing, and adjusting to
changes in work-life balance.
We should not view online learning as a temporary solution adopted due to the
COVID-19 pandemic, nor should we treat it as something that we will abandon when we
transition back to in-person learning. Studies such as Mullen’s (2020) Does modality
matter? suggested that online learning can be just as effective as in-person learning. The key
element to successful online learning is understanding and mastering the different
competencies and foci that are required to successfully and effectively design and deliver an
online course. [...
Development of an 18F radiolabeling method using solid phase chemistry
Get PDFNew radiotracers are constantly being developed to expand the clinical applications of
positron emission tomography (PET). One of the challenges in the development of PET tracers
is the incorporation of a positron emitting isotope. Short half-lives combined with added
safety measures when working with radioactive materials require a fast and simple synthesis.
This project describes a solid phase fluorine-18 (t1/2 = 110 min) radiolabeling procedure that
allows removal of impurities through filtration. The synthesis takes an indirect approach by
first labeling a small molecule with F-18 and then coupling this molecule to an amine
containing compound using solid phase dichlorotriazine (DCT).
This procedure has been used to label various compounds containing primary and secondary
amine groups without the need for an additional purification step. The total synthesis time
required is approximately 80 min from the from delivery of the [
18F]fluoride, with a decay
corrected radiochemical yield of 3% for the example tested (yield will likely vary depending
on the substrate). This demonstrates the potential of solid phase reagents like DCT to be used
in radiolabeling, but further development is required to improve yields for this reaction
The relationship between adverse childhood experiences and suicide-related behaviours in Indigenous clients seeking substance use treatment
Get PDFIndigenous populations in Canada are at higher risk of adverse childhood experiences
(ACEs; e.g., abuse, neglect, or other household challenges before the age of 18) when compared
to non-Indigenous populations. As the number of ACEs increase, so do rates of substance use
and suicide risk. In non-Indigenous populations, the presence of prior suicide-related behaviours
(SRBs) signals a need for higher intensity services within substance use treatment. This thesis
sought to better understand the relationship between ACEs and SRBs specifically amongst
Indigenous clients undergoing substance use treatment to better inform treatment planning. The
first study of this thesis analyzes previously gathered data from a community-based participatory
research program at an adult residential substance use treatment facility for Indigenous people,
while the second study of this thesis analyzes new data from culturally-validated SRB measures
incorporated into the same research program. In both studies, clients with longstanding mental
health and addictions difficulties were invited to complete two surveys during the five week
culturally informed treatment program. The first survey was administered at the beginning of the
program and measured substance use and SRBs, while the second survey was administered at the
midpoint of the program and measured ACEs. [...
Exploring the role of cannabis in fatal car crashes and a survey of Canadians’ beliefs, cannabis use behaviours and decision-making processes related to cannabis and driving
Get PDFThis mixed-method research project involved two phases investigating relationships
between cannabis use and driving. The first phase utilized data from the Fatality Analysis
Reporting System (FARS) to determine how much the odds of being responsible for a fatal car
crash increased when the driver was under the influence of cannabis. A total of 242,942 fatal
crashes met criteria for inclusion. Logistic regression analyses indicated that the presence of
THC increased the odds of engaging in unsafe driver actions by 29%. Three driver actions were
significantly associated with cannabis use: failure to keep in proper lane, driving too fast for
conditions or over the speed limit, and operating the vehicle in an erratic, careless, negligent,
reckless manner.
Phase two involved developing a new survey to assess Canadians’ knowledge, beliefs
and behaviour about cannabis products and driving. This new survey expanded on the existing
Canadian Cannabis Survey (CCS), addressing gaps, and adding novel components. After the
preliminary survey was developed, three focus groups were conducted. As a result, additional
questions and response options were added. [...
Opportunities for Indigenous fire stewardship within Ontario’s policy framework
No full textIndigenous people have used fire as a tool for thousands of years for resource
management, community protection, and cultural purposes. The criminalization of
the practice during colonization in combination with a history of government fire
suppression policies has contributed to a loss of culture and knowledge of
cultural burning in Ontario. The publishing of information on cultural burning has been
approached cautiously by Indigenous people because of the risk of non-Indigenous
people adopting practices and using them inappropriately, thereby reducing their
effectiveness. Presented in this thesis are the history of Indigenous fire stewardship, its
benefits, and Ontario’s current wildfire policy framework. Current barriers to Indigenous
Fire Stewardship are explored to recommend areas of Ontario’s policy framework where
amendments could support and increase cultural burning practices
The effect of ectomycorrhizal fungus Hebeloma longicaudum on drought stress of Pinus banksiana seedlings
Get PDFThis study looks at the influence of the ectomycorrhizal fungus Hebeloma longicaudum
to form associations and impact growth of jack pine seedlings under simulated drought
conditions. Four treatment groups of jack pine seedlings were grown for four months
and then data for dry weight, short root count, percentage and colonization of roots was
collected for each treatment group. The four treatment groups are as follows; 1.
Seedlings inoculated with an ectomycorrhizal fungus and normal watering regime, 2.
Seedlings inoculated with an ectomycorrhizal fungus and drought-like watering regime,
3. Seedlings not inoculated with an ectomycorrhizal fungus and normal watering regime,
and 4. Seedlings not inoculated with an ectomycorrhizal fungus and drought-like
watering regime. Few significant differences were found in the results of this study,
however a significant difference was observed in the number of mycorrhizal associations
between inoculated and non-inoculated seedlings (>0.01). It is thought that the lack of
significant results is primarily due to the mycorrhizal fungus not having enough time to
develop associations fully
An exploration of image recognition in archaeological starch analysis
Get PDFThe goal of this thesis was to produce a statistical method of assigning species to starch
granules recovered from eastern North American archaeological assemblages. Starch grain
analysis is an archaeobotanical tool that can be used to answer important questions about
prehistoric diet and medicine use. In eastern North America this technique can be useful in
tracking the spread and adoption of Peruvian and Mexican cultivars maize and beans, as well as
identify the use of locally occurring starch rich plants which would have been used as food and
medicines. [...
Coping motives associated with affect, anxiety, and depression after cannabis use in young adults: an ecological momentary assessment study
Get PDFBackground: Many young adults report engaging in cannabis use to manage their mood, or
affect, and psychiatric symptoms of anxiety and depression. Previous research indicates that
individuals may experience positive acute effects associated with cannabis use that obscure the
long-term detrimental effects, although findings are mixed. This may be because the acute
impacts of cannabis use are related to Cannabis Use Disorder (CUD), implying that changes are
primarily related to the alleviation of withdrawal symptoms. Acute effects could also be related
to coping motives, where individuals use cannabis in response to any distressing state, including
but not limited to withdrawal symptoms. Method: The present study examined how symptoms
of CUD and momentary coping motives are associated with acute changes in affect and
symptoms of depression and anxiety (e.g., anhedonia, worry) through multiple, short assessments
completed multiple times throughout the day (i.e., ecological momentary assessments; EMA)
before and after engaging in cannabis use. Results: Individuals with CUD did not display
significant increases in negative mood or symptoms of anxiety and depression before or after
cannabis use. Those with momentary coping motives showed significant increases in negative
affect and symptoms of anxiety and depression before use and decreases in negative affect and
symptoms of anxiety and depression after use as compared to those with other motives.
Conclusion: Results of the present study add to the body of evidence supporting that motives for
cannabis use impact the acute effects. Further, that positive acute effects of cannabis use may not
be solely related to alleviation of withdrawal symptoms seen in those with CUD, but rather,
engaging in cannabis use to manage any distressing state more broadly (i.e., coping motives)
Detecting Crohn’s disease from high resolution endoscopy videos: the thick data approach
Get PDFDetecting diseases in high resolution endoscopy videos can be done in several ways
depending on the methodology for detection. One such method that has been a hot topic
in the field of medical technology research is the implementation of machine learning
techniques to aid in the diagnosis of networks. While, this has been studied extensively
with traditional machine learning methods and more recently neural networks, major
issues persist in their implementation in everyday health. Among the largest issues is the
size of the training data needed to make accurate prediction, as well as the inability to
generalize the networks to several disease. We address these issues with a novel
approach to detecting Inflammatory bowel diseases, specifically Crohn’s disease in
endoscopy videos. We use thick data analytics to teach a network to detect heuristics of
a disease, not to simply make classifications from images. Using heuristic annotations
like bounding boxes and segmentation masks, we train a Siamese neural network to
detect video frames for ulcers, polyps, erosions, and erythema with accuracies as high
as 87.5% for polyps and 77.5% for ulcers. We then implement this network in a protype
frontend that physicians can use to upload videos and receive the processed images in
an interactive format. We also pontificate as to how our approach and prototype can be
expanded to several diseases with learning of more heuristics
Light-weight federated learning with augmented knowledge distillation for human activity recognition
Get PDFThe field of deep learning has experienced significant growth in recent years in various
domains where data can be collected and processed. However, as data plays a central role in
the deep learning revolution, there are risks associated with moving the data from where it is
produced to central servers and data centers for processing. To address this issue, Federated
Learning (FL) was introduced as a framework for collaboratively training a global model on
distributed data. However, deploying FL comes with several unique challenges, including
communication overhead and system and statistical heterogeneity. While FL is inherently
private as clients don’t share local data, privacy is still a concern in the FL context since
sensitive data can be leaked from the exchanged gradients.
To address these challenges, this thesis proposes the incorporation of techniques such as
Knowledge Distillation (KD) and Differential Privacy (DP) with FL. Specifically, a modelagnostic FL algorithm based on KD is proposed, called the Federated Learning algorithm
based on Knowledge Distillation (FedAKD). FedAKD utilizes a shared dataset as a proxy
dataset to calculate and transfer knowledge in the form of soft labels, which are then sent
to the server for aggregation and broadcast back to clients to train on them in addition
to local training. Additionally, we elaborate on applying Local Differential Privacy (LDP)
where clients apply gradient clipping and noise injection according to the Differentially Private Stochastic Gradient Descent (DP-SGD). The FedAKD algorithm is evaluated utilizing
Human Activity Recognition (HAR) datasets in terms of accuracy and communication efficiency