3855 research outputs found
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Investigating the role of prostaglandin system dysregulation in radiation resistance of triple negative breast cancer cells
No full textThe overall goal of this research program was to elucidate the molecular mechanisms underlying radiation resistance in breast cancer. Prostaglandin (PG) signaling dysregulation has been implicated in various aspects of cancer progression, including tumor growth, metastasis, and inflammation, but its potential role in promoting radiation resistance remains underexplored. Among the key components of the PG system, prostaglandin-endoperoxide synthase 2 (PTGS2) emerged as a critical mediator potentially driving this resistance mechanism. Therefore, the primary aim of this study was to investigate the role of PTGS2 dysregulation in the development of radiation resistance in triple-negative breast cancer cells. To address this gap, radiation resistant variants of MDA-MB-231 cells were generated by repeated exposures to x-ray radiation (57 Gy total dose) followed by clonal cell selection. RT-qPCR and Western blot analysis revealed robust upregulation of PTGS2 mRNA and protein expression in radiation resistant cells compared to the parental MDA-MB-231Control cells. Whole-transcriptome analysis further corroborated these results, whereby radiation resistant variants demonstrated a 16.7-fold (p<0.05) increase in PTGS2 mRNA expression. In addition, 6 Gy radiation challenge further increased PTGS2 expression 48 hours post radiation exposure (76% increase; p<0.05) in radiation resistant variants, whereas the MDA-MB-231Control cells showed lack of PTGS2 expression changes. The next goal was to determine whether the upregulation of PTGS2 expression in MDA-MB-231 cells promoted the development of radiation resistance. Here, PTGS2 was overexpressed using the CRISPR/dCas9 system, and expression was verified using RT-qPCR and Western blotting. Surprisingly, PTGS2 overexpression led to decreased survival following radiation exposure. This suggests that although PTGS2 is upregulated in radiation-resistant cells, its overexpression alone makes the cells more susceptible to radiation-induced damage. In addition, PTGS2 overexpression reduced adhesion to fibronectin and increased anchorage independent growth. These changes suggest that PTGS2 promotes a more aggressive cancer phenotype by enhancing cell detachment and survival in non-anchorage conditions. Taken together, this study highlights the role of PTGS2 in the development of radioresistance, suggesting that PTGS2 and its downstream effectors within the prostaglandin signaling pathway may serve as promising therapeutic targets for therapy resistant cancers
Injury prediction for Canadian mineral exploration using machine learning and time series
No full textThe mineral exploration industry, vital to Canada's economy, is also one of the most hazardous sectors, with workers facing significant risks of severe injuries or fatalities. This research focuses on improving occupational health and safety by predicting nature of injury within the industry. Utilizing an extensive dataset from the Prospectors and Developers Association of Canada (PDAC), the study applies advanced machine learning (ML) techniques to forecast injury severity across four classes. Eight ML methods, including Support Vector Machine, Convolutional Neural Network, Bayesian Neural Network, and more, along with four time series methods, were used. The findings offer critical insights into injury patterns, enabling the development of enhanced safety protocols. By providing quantitative predictions, this research aims to reduce injury rates and improve safety measures in the mineral exploration sector, contributing to a safer working environment
Public knowledge, attitudes, and awareness of cyanobacterial health effects in Central Ontario, Canada
No full textCyanobacterial blooms are becoming more frequent and widespread, with potential health risks for people exposed to toxins through recreational water use. This study examined public knowledge of cyanobacteria and exposure prevention in the Simcoe/Muskoka region of Ontario, using mixed methods consisting of content analysis of 100 news media articles and survey responses from 110 participants. News media articles varied in quality; 33% explained how to identify a cyanobloom, and 49% provided advice on avoiding contact. The survey found that 71.8% of respondents primarily relied on news media for information. Participants expressed moderate concern about cyanobacteria (average rating 71.7/100), but 36.7% could not identify symptoms of cyanotoxin exposure, and 30% were unaware of cyanobloom signs. Among those who could identify cyanobloom signs, confidence was low (average rating 21/100). Overall, while news media coverage lacked crucial illness-prevention details, the public showed some awareness of how to reduce exposure risks
A mathematical programming framework for stope and production scheduling optimization: a stochastic integrated approach
No full textThis research presents a comprehensive study that focuses on optimizing the operational aspects of underground mining processes through a sophisticated modeling framework. The study introduces a Stochastic Mixed Integer Linear Programming (SMILP) framework that evolved from an initial Mixed Integer Linear Program (MILP) model. This advanced model considers a wide range of mining operations, including primary (decline) development, ventilation development, operational development, ore pass development, stope design and extraction, as well as backfilling and stockpile management. The primary aim of this research is to enhance the economic efficiency and sustainability of mining projects by optimizing the extraction and management of mineral resources. The research objectives encompass the following key aspects: a) a comprehensive framework has been proposed and developed to address production scheduling optimization while considering primary, ventilation, and operational developments, as well as backfilling, ore pass, and stockpile management; b) accounting for geological uncertainties, the research delves into techniques for incorporating stochastic variables, such as ore grade, into the optimization framework. This addition ensures a more realistic representation of the mining environment and its associated uncertainties; c) the framework has been extended to maximize the Net Present Value (NPV) of an integrated stope design and production scheduling optimization. This approach ensures that the economic viability and profitability of mining projects are at the forefront of decision-making processes. The research encompasses a holistic exploration of these objectives, culminating in the development and validation of the SMILP model.
The successful integration of mathematical modeling and optimization techniques into the mining industry addresses the challenges posed by geological uncertainties, infrastructure development, extraction methodologies, and resource management. The execution of the research was facilitated by the effective implementation of all constraints and objectives using the MATLAB programming language. Complex problem-solving was achieved through the utilization of IBM ILOG CPLEX, a powerful optimization solver.
To investigate the practicality and performance of the proposed model, six comprehensive case studies were conducted. These case studies aimed to analyze and compare the economic and operational outcomes when employing the SMILP model. The primary performance metric used in these case studies was the NPV, a crucial indicator of a project's economic viability. Among the case studies presented, the SMILP model with stockpile management (Case 4) exhibited superior performance, reporting the highest NPV when compared to the other five cases. Case 4 achieved a 25-year mine life production schedule with a generated NPV amounting to 7,801.20 M, indicating a 4% increment in financial gain by the SMILP model. These findings underscore the effectiveness and practical applicability of the developed model in real-world mining scenarios.
In conclusion, this thesis represents a substantial contribution to the field of mining engineering and operations research. It offers a robust and versatile framework for optimizing underground mining processes, considering various uncertainties and constraints. The research outcomes have the potential to significantly enhance the economic prospects of mining projects, making them more sustainable and profitable. This work not only contributes to the advancement of mining science and engineering but also holds promise for improving the efficiency and sustainability of mining operations in the real world
The ice has memory: food sovereignty, country food and land-based practices explored through resilient architecture in Gjoa Haven, Nunavut
No full textLand in the Arctic is dynamic, with its seasonal changes
of freeze and thaw, light and dark, it is a transformative
being. However, over the past decade, land has been shifting
drastically in the north, global warming has begun to strip
away the layers of, history, geology and culture, revealing an
unfamiliar terrain to navigate for residing Inuit communities.
The frozen terrain that makes up the permafrost and sea ice
are beginning to thaw rapidly. And the physical ground,
once thought to be stable, is becoming increasingly fluid.
These radical transformations and conditions have created a
cultural displacement for Inuit communities, who have relied
generationally to be on the land to hunt, harvest, travel and live.
As a result, the dire impacts of climate change have displaced
the traditional ways of life and being on the land, specifically
concerning the right to access culturally appropriate and
nutritious food. Therefore, this thesis aims to explore how
architecture can culturally respond and accommodate spaces
for traditional land-based hunting, harvesting and wellness
practices through resilient design frameworks.Master of Architecture (M.Arch
A textural and trace-element study of pre-ore pyrite types at the Kamoa-Kakula sedimentary-rock-hosted copper deposit, Democratic Republic of Congo
No full textPyrite is known or assumed to be an important precursor phase in a variety of sedimentary-rock-
hosted ore deposits. The probable role of framboidal pyrite has been identified in the origin of
the giant Kamoa-Kakula Cu deposits in Democratic Republic of Congo, which are hosted by
multiple-km-thick mid-Neoproterozoic diamictite, but the nature and paragenesis of pre-ore
pyrite(s) in the system is poorly known. Using samples from a least-altered, least-mineralised
drill-hole, this study identified and characterised four types of pre-ore pyrite in the Kamoa-
Kakula system: (a) framboidal (‘sedimentary’) pyrite; (b) aggregate pyrite, consisting of irregular
patches of pyrite microcrysts; (c) microcrystalline euhedral pyrite, consisting of independent
very small euhedra; and (d) cluster pyrite, characterised by inclusion-rich amorphous centres
overlain by groups of large, interlocking, inclusion-free euhedra. Textural relationships indicate
that framboidal pyrite formation was followed by euhedral pyrite, aggregate pyrite, and then
cluster pyrite. There is no textural evidence that euhedral or aggregate pyrite formed through
recrystallisation of framboids. Trace element geochemistry indicates that framboidal, aggregate,
and (some) euhedral pyrite formed under related, early diagenetic conditions, whereas (most)
euhedral pyrite and cluster pyrite formed later, under different (“hydrothermal”) geochemical
conditions. The trace element geochemistry indicates that, in contrast to the textural evidence,
the paragenetic order of the pre-ore pyrite types is framboidal, aggregate, euhedral, and cluster.
An ore-phase pyrite (clast-rimming pyrite) is texturally and geochemically distinct from all four
pre-ore pyrite types.Master of Science (MSc) in Geolog
La pensée critique dans la formation en kinésiologie : un examen des conceptions des formateurs et formatrices universitaires de l'Ontario en regard à sa nature, ses rôles et les modalités de son développement.
No full textCette étude vise à explorer les conceptions de la pensée critique des formateurs et des formatrices
universitaires en kinésiologie de la province de l’Ontario. Plus précisément, elle cherchait à
identifier et à décrire leurs conceptions concernant la nature, les rôles et les modalités de
développement de la pensée critique. Une méthodologie mixte a été employée. Trente formateurs
et formatrices universitaires en kinésiologie de la province de l’Ontario ont volontairement
participé à un sondage par questionnaire. Les données recueillies ont été analysées selon la
technique de statistique descriptive. Les résultats ont montré des conceptions diverses, alignées sur
des perspectives philosophiques, psychologiques, psychopédagogiques, de la théorie critique et de
la pédagogie critique. Les enseignant.e.s universitaires considèrent que la pensée critique joue un
rôle crucial dans le développement des compétences analytiques et décisionnelles des étudiants.
Ils ont indiqué l'utilisation de stratégies d'enseignement multiples et d'études de cas,
l'apprentissage par problèmes et les projets pour développer la pensée critique des étudiants. Dans
l'ensemble, l'étude a mis en évidence la diversité de conceptions de la pensée critique en
kinésiologie et l'importance des approches mixtes pour son développement.Maîtrise en Kinésie Humaine (MKH
The effects of message framing on food choice
No full textAs unhealthy eating habits and nutrition-linked health problems continue to pose significant
public health concerns, understanding the effects of health communications has become crucial
in promoting healthier food choices. The current research sought to understand the effectiveness
of message framing and evidence type on food choice. The current study exposed participants to
messages that described either the gains associated with eating healthy foods, the losses
associated with eating unhealthy foods, or non-nutritional messages. Messages also manipulated
whether they conveyed information using a narrative or statistical format. Data from the 3
(message framing: gain-framed, loss-framed, and control) x 2 (evidence type: statistical versus
narrative) between-subject design showed that both gain-framed and loss-framed conditions
promoted more healthy food choices than the control conditions. However, manipulating the
evidence type did not persuade participants to make healthier food choices. Moreover, the results
did not identify a significant interaction between message framing and evidence type.
Implications of the current study are useful for understanding how health communication
messages can influence people’s food choices, and aid policymakers in developing persuasive
health communication campaigns.Master of ARts (MA) in Psycholog
Supporting the Northern Ontario Equestrian Community: Re-Imagining the Sudbury Downs Raceway
No full textThis thesis explores how identified architectural & non-architectural challenges in the Northern Ontario Equestrian Community can be addressed through a design proposal at the Sudbury Downs Raceway. The relationships identified by contextualizing shifts in past to present horse/ human relationships include the constant capacity for change in the equine sector. This has broad architectural implications for equine spaces that don’t always adequately center both equine and human wellness. By engaging in interviews with members of the equestrian community, this thesis assesses specific challenges and opportunities, including: access, affordability, design standards, and existing infrastructure. Thematic analysis findings from the interviews informs the scope of the design proposal. Reviving the Sudbury Downs Raceway as an equestrian horse park aims to provide a central hub for the local equestrian community, including nearby townships within Northern Ontario, while providing space for the broader Sudbury population through shared programming.Master of Architecture (M.Arch
Quantification of turtle capture efficiency and the impact of development on plant communities within community-selected priority areas in Eastern Georgian Bay
No full textA worldwide biodiversity crisis coupled with rapid and irrevocable habitat destruction have
caused many conservation groups and local communities to identify research and conservation
priorities. In the Eastern Georgian Bay region of Ontario, linear developments such as roadways
and transmission lines destroy and fragment pristine upland and wetland habitats, and are likely
to have measurable effects on local ecology. Local First Nations, not-for-profits, and
municipalities identified several habitats adjacent to linear developments as conservation priority
areas, and turtle and plant communities affected by those linear developments as research
priorities. The objective of my study was to provide communities with site-specific ecological
data to inform their decision-making as they navigate land-use changes within local habitats.
More specifically, I provided local partners with (i) turtle community census data, which I also
used to assess the efficiency of different survey methods for turtles, and (ii) plant community
census data, which I also used to assess how linear developments are affecting their overall
health and composition. During my turtle community research, I located 772 turtles and found
that survey efficiency (number of turtles caught per unit sampling effort) increased with warming
temperatures in early spring, and that using multiple sampling methods may help decrease
taxonomic and size biases. During my plant community research, I assessed the distribution of
10 tree species and 63 understory species across 150 upland forest plots at Magnetawan First
Nation, which revealed that linear developments are affecting functional and taxonomic diversity
of plant communities and facilitating establishment of introduced species. Overall, my study
highlights the value in local partnerships, provides survey efficiency recommendations for
freshwater turtle populations, and provides evidence that linear developments are or will
negatively affect turtle and plant communities in the Eastern Georgian Bay region.Master of Science (MSc) in Biolog