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Exploring the impact of passion engagement on the resilience of older adults during the covid-19 pandemic
No full textEngaging in a passionate activity can be helpful. According to the Dualistic Model of Passion (DMP; Vallerand et al., 2003), passionate activities are described as either harmonious or obsessive. Harmonious passion have been associated with beneficial outcomes (e.g., affective and psychological well-being), while obsessive passions have been linked to deleterious outcomes (e.g., high negative affect and ill-being). Resilience refers to the ability to recover from adversity. Many protective factors that bolster resilience are also associated with harmonious passions. It was hypothesized that older adults with a harmonious passion would be more resilient than their obsessively passionate counterparts. Resilience was represented by a multivariate construct, encompassing adversity (i.e., psychological distress), positive adaptation (i.e., well- being), and protective factors. Using a sample of community-dwelling older-adults (n=92), this multivariate model was compared across harmonious and obsessive groups, with results indicating that passion groups did not differ. Additional exploratory analyses were conducted, wherein each component of resilience was compared across passion groups. The harmonious group scored higher on a measure of protective factors and lower on measure of adversity. No differences were noted for positive adaptation. This suggests that the overall resilience and positive mental health of older adults outweighed any differences due to passion orientation
Investigating the immune modulating effects of low dose ionizing radiation as a potential cancer therapy
No full textIonizing radiation is an established treatment modality for cancer. Unlike targeted high dose therapies,
there is growing evidence that low dose radiation (LDR) can promote tumor reduction indirectly via
stimulation of the immune system. Natural killer (NK) cells are one of the main immune cells that have
been implicated in LDR induced anticancer effects. Despite this, the exact cellular and molecular
mechanisms responsible for the modulation of the immune system following LDR, including the
stimulation of NK cells and their cytotoxic properties, have not yet been identified. The goals of this
study were twofold; to elucidate the cellular mechanisms involved in LDR immune stimulation and to
investigate the dose response for NK cell cytotoxicity. Initially, a small animal model was used to
comprehensively characterize the dose dependent effects on various immune cells. Mice were exposed
to whole-body x-ray doses of 0.1, 0.25, 0.5 and 3 Gy and were sacrificed two days post-irradiation for
isolation of their spleen, lymph nodes and blood. Flow cytometry was then used for
immunophenotyping to identify potential shifts in the relative abundance of major immune cell
populations. Data from this cohort of mice suggested that 2 days following an acute single exposure,
LDR caused no significant changes in the numbers of the immune cell types tested, and that high dose
radiation (HDR) caused a decrease in the cell populations of these cells in the irradiated mice. To
further investigate the impact of LDR on the NK cells in-vitro, the NK-92 cell line was used. NK-92
cells were exposed to x-ray doses ranging from 0.1 to 1 Gy, and cell growth rates were measured postradiation. NK cell cytotoxicity was then quantified through the co-culturing of NK-92 cells with the
tumorigenic K-562 cells, and the percent cytotoxicity was measured using flow cytometry. Lastly,
transcriptional analysis was performed on the main genes involved in regulating NK cytolytic activity.
Overall, data showed that LDR did not cause any significant increase in the growth, cytotoxicity and
gene expression of NK-92 cells. To conclude, although no evidence of immune stimulation was found following LDR in both the mice model and NK-92 cell line, this study was successful in providing a
good characterization of the baseline immune response to lower doses of radiation in healthy models.Master of Science (MSc) in Chemical Science
The Red + Green: creating a regenerative narrative through the industrial wastelands of Sudbury, Ontario
No full textSudbury, Ontario, is recognized for its miraculous late
twentieth-century Regreening efforts to remediate the
smelter-polluted ‘moonscape.’ Yet, given the continued
extractive activity and unmanaged mine waste, some areas
remain subject to extensive environmental degradation.
Therefore, a critical reflection on these industrial practices is
necessary to continue this incomplete regenerative narrative,
fully restoring all parts of the land. Thus, this thesis is informed
by research into innovative ground surface treatment and
biotechnologies to treat mine waste, and in regenerative
architectural design principles. It demonstrates the potential
of lifting the veil on hidden industrial wastelands, rehabilitating
Copper Cliff’s Central Tailings Area into a thriving regenerative
park, and envisioning an interpretive centre into a mine waste
facility that is harmoniously integrated into the changing
landscape. This contributes to landscape remediation and
integrates place-based storytelling to educate and empower
future generations to participate in land stewardship and create
ongoing sustainable environmental and social impacts.Master of Architecture (M.Arch
Numerical modeling and investigations of oxygen transport in microcirculation
No full textSeveral aspects are involved in the oxygen transport in capillaries, such as the red blood cell (RBC) membrane mechanics, the cytoplasm/plasma flow fields, and the mass transport across the semipermeable deformable membrane. The transport process is also influenced by association and dissociation kinetics, which considers the interaction between oxygen and hemoglobin molecules within the RBCs. Therefore, a model of oxygen transport must include these factors to accurately represent the process. In chapter 1, the microcirculation system, human RBC structure and properties, and oxygenhemoglobin kinetics have been briefly introduced to provide basic background information for oxygen transport process in microcirculation. Then, the effects of several important factors (RBC shape, plasma/cytoplasm convective effect, RBC membrane treatment) on gas transport in microcirculation have been reviewed. The literature review has shown that an efficient and robust numerical scheme for simulating oxygen transport in capillaries is missing and the effects of RBC properties and behaviors have not been well addressed. The motivation of this Ph.D. research is to develop a transport model to study the effects of various RBC flows on oxygen transport in capillaries. Several specific research objectives have been outlined in Section 1.5. In Chapter 2, we propose a new method called the immersed membrane method for mass transfer across flexible semipermeable membranes. This method is based on the classical immersed boundary method used for interaction between structures and flow, and it replaces the sharp interface of the membrane with an artificial fluid layer. This layer does not affect the fluid flow or the membrane deformation, but it does add resistance to mass transiii fer, based on the membrane’s original permeability. By using this approach, we can solve the mass transfer problem using a single numerical scheme on the same Eulerian mesh, and we can avoid the complicated interface treatment required for the membrane interface condition. We also validated this method by comparing numerical results with theoretical solutions, and satisfactory agreement has been observed. In Chapter 3, we consider a tank-treading capsule in shear flow, which is generated with two parallel plates moving in opposite directions: the top plate represents the core of RBCs in a microvessel with a high oxygen pressure (PO2 ), while the bottom plate represents the microvessel wall with a lower PO2 . Numerical simulations are conducted to investigate the individual and combined effects of cytoplasm convection and oxygen-hemoglobin (O2-Hb) reaction on the oxygen transport efficiency across the tank-treading capsule, and different PO2 situations and shear rates are also tested. In Chapter 4, we conduct numerical simulations for the blood flow and RBC deformation along a capillary and the oxygen transfer from RBCs to the surrounding tissue. We look at different values of capillary hematocrit, the oxygen tension in the arterioles, and metabolic rate of oxygen consumption. Our results show that there are two competing factors that affect the tissue oxygenation while the capillary hematocrit increases: the positive effect of higher RBC density and the negative effect of the slower RBC movement; and the relevant strength of these two mechanisms is related to the oxygen-hemoglobin reaction and hemoglobin concentration and affinity in cytoplasm. In Chapter 5, we simulate the oxygen uptake processes in stopped-flow experiments with different cell shapes, membrane permeability and unstirred layer thickness considered. Our results show that the uptake process from the spherical model is much slower than those from the ellipsoidal and biconcave shapers, meaning that results form previous studies using spherical cell models may need to be revisited. Also we find that it is difficult to distinguish the individual influences from the membrane permeability and unstirred layer, and more comprehensive models will be required for future studies. At last, in Chapter 6, concluding statements and future work based on the research results are presented
Metallogeny of the Powell Block, Rouyn-Noranda Mining District, Québec
No full textThe Rouyn-Noranda mining district of Québec is located along the southern margin of the
Abitibi greenstone belt of the Archean Superior Province. It hosts 22 Cu-Zn-Au-Ag volcanogenic
massive sulfide (VMS) deposits, distributed amongst four fault blocks (Hunter, Flavrian, Powell
and Horne). The Powell Block hosts the Au-rich Quemont VMS deposit and separates the Horne
deposit, a world class Au-rich VMS deposit, from conventional VMS deposits (≤ 1 g/t Au) north
of the Beauchastel fault. The structural and stratigraphic evolution of the Powell Block is poorly
constrained and as a result, the time-stratigraphic position of the Quemont deposit relative to the
Horne deposit and deposits of the Flavrain Block is uncertain, as are the processes responsible for
the anomalous gold content of the Horne and Quemont deposits. Gold-quartz-carbonate and
quartz-sulfide (Cu-Ag-Zn) epigenetic veins are also present, but their origin and relative timing
remain enigmatic.
The Powell Block can be subdivided into two distinctive domains, the Brownlee and Joliet
domains, representing two overlapping volcanic centres. These two domains both consist of lower
Blake River Group volcanic strata that differ slightly in age and volcanic history. The Brownlee
domain is characterized by mafic dominated, bimodal volcanism (ca. 2701 Ma), whereas the Joliet
domain is characterized by a thick sequence of felsic coherent and volcaniclastic units (≥2702 Ma).
Two base metal mineralizing hydrothermal events are recognized. An early event is related to
voluminous felsic volcanism, concomitant subsidence and the formation of the Quemont and
Horne deposits in the Joliet domain and Horne block, respectively. These two deposits formed
within the district’s largest monogenic felsic volcanic centre in a subaqueous setting that was
locally emergent. Given this setting, the Au-rich Quemont and Horne deposits may have had a
more direct magmatic input resulting in higher Au grades than the Cu-Zn VMS deposits of the Flavrian Block, which formed in a mafic dominated, bimodal, effusive and perhaps, a deeper water
volcanic setting. A later hydrothermal event at ca. 2699~2695 Ma is related to the formation of
disseminated, vein and breccia hosted (e.g. Joliet Breccia) quartz-sulfide (Cu-Ag-Zn) mineral
occurrences, with variations in deposit characteristics reflecting differences in depth of formation
and proximity to a magmatic source. The lateral zoning of alteration types, compositional gains
and losses, and metal tenor are similar to VMS footwall alteration zones within the district and
elsewhere, and these breccias and veins are part of a broad continuum of subsurface, cross-stratal
magmatic-hydrothermal mineralization to seafloor, stratiform, VMS mineralization, a spectrum
akin to the porphyry-epithermal continuum of modern subaerial volcanic arcs.
Approximately 30–40 m.y. later, gold-quartz-carbonate veins were emplaced during N-S
shortening of the volcanic rocks. Superposition of alteration related to these younger veins
perturbed and masked regional alteration patterns related to the Quemont and Horne deposits, but
due to their restricted distribution and comparatively low-grade, did not substantially affect the
original gold tenor of these VMS deposits.Doctor of Philosophy (PhD) in Mineral Deposits and Precambrian Geolog
Exploring the feasibility, suitability, and benefits of an arts-based mindfulness program for adolescent mothers
No full textThere is a growing interdisciplinary body of research on adolescent motherhood that offers
perspectives from sociology, social work, education, psychology, and health disciplines.
Researchers have highlighted that many adolescent mothers experience high levels of
psychological distress which is often attributed to the challenges of parenting with daily stress,
limited support, and cumulative disadvantage. As a result, achieving maternal sensitivity can be a
challenge for many adolescent mothers due to their developmental stage, and the stresses in their
lives. Mindfulness-Based Interventions (MBIs) are increasingly being used to help improve
parenting, prevent chronic parenting stress, and break the cycle of dysfunctional parenting patterns
and behaviors. However, there is limited research that explores the suitability of this type of
intervention with this population. The aim of my research was to explore the feasibility and
benefits of an arts-based mindfulness intervention program for adolescent mothers. My research
process began with a scoping review of the literature to explore how mindfulness and arts-based
methods have been studied with the adolescent parenting populations. The search did not yield any
articles that described the use of MBIs with the adolescent parenting population. However, I
identified 10 articles in which authors described arts-based parenting interventions with adolescent
mothers. Participants from these studies reported that engaging in arts-based activities enabled
them to develop ways to positively interact with their children, resulting in greater attunement to
their children. The second phase of this research project involved exploring the feasibility and
suitability of an online arts-based mindfulness program for adolescent mothers during the COVID19 pandemic. This paper describes my experiences, challenges, and thoughts on the suitability of
offering arts-based mindfulness programs online to adolescent mothers. Several challenges were
encountered with respect to engagement and facilitation including high attrition rates and numerous disruptions during programming. The last phase of my research explored the feasibility,
suitability, and benefits of offering an arts-based mindfulness program to adolescent mothers in
person. In the third paper, I describe the experiences of nine adolescent mothers who attended an
11-week arts-based mindfulness program. From my findings, I concluded that arts-based
mindfulness group programs are an effective way to engage adolescent mothers in interventions
that help them develop supportive relationships, positive coping strategies, and improved
awareness of themselves and their children. My research has direct implications for service
delivery and for the development of care models for adolescent mothers that go beyond a focus on
physical health, to a more holistic approach to assessment and intervention.Doctor of Philosophy (PhD) in Human Studie
Reconciliation of Indigenous and non-Indigenous youth through leadership programs
No full textReconciliation in Canada has been moved to the forefront with the recent publication of the
findings of the Truth and Reconciliation Commission. Youth can play a significant role in
achieving reconciliation in Canada. In the following research, I propose that building balanced
relationships during adolescence can counteract the disparity between Indigenous and
non-Indigenous youth and lead to reconciliation. These relationships can be encouraged through
creating shared experiences in leadership programs that include forums for discussions and
cooperative development. Over a five-year period, youth from a remote Northern Ontario First
Nation reserve have participated in two-week leadership training programs at a resident summer
camp in central Ontario. I was motivated by the benefits of the ensuing relationships between the
Indigenous and non-Indigenous youth, which led to this instrumental case study of the
reconciliation potential of camps. I explored the outcomes of the interactions between the youth
and staff at the camp. The methodology for this research includes a literature review and
collecting data in interviews with the participants. Documents from the camp were analyzed to
understand the values, vision and approach of the camp. The data was analyzed and five main
areas became evident and were studied: values, goals, relationships, development and
community. The safe environment carefully created at the camp led to relationship building
between Indigenous and non-Indigenous participants and the non-Indigenous participants grew
somewhat in their understanding and acknowledgement of Indigenous issues. As this
instrumental case study was based on a small sample and the program was not set up to
intentionally address reconciliation, the impact was limited. With a more direct attempt, there is
potential for reconciliation in youth camp programs. By creating experiences where youth can
interact and build relationships, they can build a better understanding of each other and thus
create social solidarity.Master of Indigenous Relations (MIR
Co-habitat: innovative solutions for coexistence between the human and non-human within the Port Lands
No full textHow can architecture foster cohabitation through the multiple scales of the built environment? Part of this
answer lies within the theoretical framework which explores ecological urbanism, specifically through the theories
of landscape as a medium, biophilia, and wildlife inclusivity. The other part of the answer is a study of the building
components and architectural forms informed by case studies of green buildings. This will impart the move to
integrate nature within the site of Villiers Island, located in the Toronto Port Lands. The site is part of an ongoing
revitalization project and an active bird flyover. The issue with the current master plan is that it proposed a harsh
divide between the urban and natural ecosystems, causing the conflict. As humans dominate a large part of the
Earth, the goal is to seek cohabitation for both humans and non-humans within this new ecosystem through a midrise, mixed-use residential buildingMaster of Architecture (M.Arch
Facilitating grief and fostering remembrance through architecture and landscape
Get PDFToday’s multicultural and spiritually non-religious Western
society seems to be moving away from notions of death
and the grief caused by it, requiring its concealment to
avoid disrupting everyday life. This is evident in how society
stigmatizes public expressions of grief and the apparent
lack of virtual and physical spaces outside of homes and
institutions. Society has limited space for grief, and we are
left to our own devices to navigate the complex, confusing,
and painful experience of bereavement. Considering the
important role the physical world and our bodies have
in accessing memories, this research will navigate the
expansive field of grief research and implement a crossover
to the field of architecture. Through photo documentation
and a process of making, this research suggests grief-related
spaces can be expanded outside of homes and institutions
to provide accessible therapeutic spaces that facilitate the
various needs of the bereaved and foster remembrance.Master of Architecture (M.Arch
Crop disease detection using deep learning techniques on images
No full textAgriculture is a field which is referred to as the main sector for the development of the economy
in various countries, and it is also providing food to the large population of the world despite
various limitations and boundaries. Food security is threatened by several factors including climate
change, the decline in pollinators, plant diseases and others. Different efforts have been developed
to prevent crop loss due to infections in the plants. The advancement in technology is helping
farmers in developing different systems that can help in reducing the problem. Smartphones
specifically offer very novel ways to identify diseases because of their computing power, high
resolution displays, and extensive built-in sets of accessories, such as advanced HD cameras. This
leads to a situation where disease diagnosis based on automated image recognition is needed.
Image recognition is made possible by applying a deep learning approach. So the research is aimed
to analyze deep learning-based image detection techniques to identify the various diseases in the
plants. The “PlantVillage” dataset has been used to train models. Deep learning Architectures such
as AlexNet and GoogleNet, ResNet50 and InceptionV3 are used. Two approaches are used to train
the model: ‘training from scratch’ and ‘transfer learning’. It was found from the results of the
primary analysis that the GoogleNet leaves behind the AlexNet, ResNet50 and InceptionV3 in
training from scratch approach. And ResNet50 performed best in transfer learning.Master of Science (M.Sc.) Computational Science