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Survival analysis and prediction of lung cancer in patients based on clinical and image features using machine learning
Get PDFLung cancer develops in lung tissues, most commonly in the cells that line the airways. It is the leading cause of death from cancer in both men and women. To estimate the prevalence of lung cancer in the coming years, it is necessary to diagnose it in the early stages. This thesis work proposes
to perform a reliable diagnosis of patients with lung cancer. The goal of this research is to analyze the important variables impacting lung cancer based on p-value using image features as well as clinical data and is focused on quality analysis. Further, to enable early diagnosis of cancer with high efficiency, this work proposes to classify the patient’s images into cancer using a Convolutional Neural Network (CNN) to enable its early diagnosis. The thesis discusses the dataset, data pre-processing steps, survival rate risk analysis, classification, and performance evaluation of the process. This study used two kinds of data, clinical and image data. The Genomic Data Commons (GDC) Data Portal and The Cancer Imaging Archive (TCIA) were used as the data source. The Random Forest regression estimation method was used to fill in the missing values. It first imputes all missing data with the mean/mode, then fits a random forest on the observed part and predicts the missing part for each variable with missing values. Three models are used to test the significance of variables on cancer survival rates: Kaplan Meier (KM), Cox Proportional Hazards (CPH), and Accelerated Failure Time (AFT). The analysis took into account three types of data: clinical only, image only, and combined clinical and image data. All three models have been effectively applied and the outcome revealed the most robust data and the crucial variable to be focused upon for further experimentation. For classification, a Convolutional Neural Network (CNN), with low
computational cost and time overhead is used. The output of statistical models demonstrates the robustness of image data among all types, as it has the fewest chances of producing false results.
Image data, which is common in clinical data collection is less prone to human error. As a result of the data's robustness, only image features data was preferred over clinical data and combined in the next step to perform the classification of images for cancer prediction. Based on the accuracy, the CNN results were compared to the two other ensemble approaches, Random forest (RF) and XgBoost. CNN achieved an accuracy of 99% in image classification, which was higher than the accuracy rates of Random forest (RF) and XgBoost, which were 95.83% and 95.83%, respectively.
As a result, the CNN model can be applied to new Computerized Tomography (CT) scan images for lung cancer diagnosis to conduct additional research and to assist clinicians
Reshaping Canada's second home: how social collaboration can be promoted by the adaptive re-use of an old community rink
No full textGiven Canada’s northern climate, winter sports and particularly skating,
have assumed tremendous cultural importance, yet nearly half of the
skating facilities in the country are approaching or have reached their life
expectancy. This owes to the interrelated challenges of the expense of
maintaining rinks and arenas, and the fact that they are only used during a
few months of the year. This thesis takes the position that the adaptive reuse
of an existing arena to host multiple programs is the most culturally and
environmentally sustainable response to serve the surrounding community.
Founded in Guelph, Ontario, in 1871, Exhibition Park is a well-used public park
offering an assortment of recreational amenities and community-inclusive
programs. However, the latent potential of the park’s dated arena merits
exploration. This thesis proposes the adaptive reuse of Exhibition Park Rink
into a dynamic year-round cultural centre that provides an improved skating
experience, alongside complementary community programs.Master of Architecture (M.Arch
Design and verification of a Hydraulic Air Compressor as a CO2 capture and sequestration system.
No full textAs a result of human activities, the level of atmospheric carbon dioxide (CO2) has increased.
Carbon capture and sequestration (CCS) technologies offer an effective approach for mitigating
CO2 from various industrial process to reduce the global climate change effect. These technologies
can be integrated into existing infrastructure with minimal disruption. This study reviews on post-
combustion CO2 capture and sequestration techniques, with a specific focus on mineral
carbonation process routes and their potential feedstocks. Mineral carbonation is an approach that
mimics the natural weathering of rock, in which metal oxide-bearing materials, for instance natural
silicate minerals (serpentinite, olivine) react with gaseous CO2 to form solid carbonates. This
process takes place on geological time scales, but it can be accelerated by increasing the
concentration of CO2 in a reactor through pressurization of the system.
The purpose of this study was investigation of technical feasibility of a CCS process by means of
a hydraulic air compressor (HAC). A series of experiments were conducted on the HAC pilot plant
to investigate the potential of the system as a post-combustion CO2 capture system. Those
experiences experimentally verified a one-dimensional steady-state model for two-phase bubbly
flow. The verified bubbly flow model was used to compare the hydrodynamics and mass transfer
characteristics of HAC downcomers and upward co-current flow bubble column reactors and to
predict gas liquid mass transfer coefficients.
The experimental results showed that the HAC is an effective technology for intensification of
CCS processes due to its improved mass transfer performance compared to other mass transfer
devices. While the high capital cost of HAC construction, following a general Millar (2014) design paradigm, limits applicability, the horizontal injector loop (HIL), developed in this thesis offers a
new apparatus with similar gas compressor performance and reduced height, which would make
the concept more accessible for capital restricted projects.
A mathematical dynamic kinetic model is developed to simulate the kinetics of CO2 absorption
into an alkaline solution in the HIL. This model makes a significant contribution in predicting the
absorption rate under operating conditions beyond those achievable in experimental tests
undertaken. In addition, this model can be used to guide the design of a new reactor and future
experiments, making it a valuable tool for CO2 capture and sequestration activity.
Carbon dioxide capture and sequestration by means of a HIL as a pressurized, continuous chemical
reactor was also investigated experimentally. The experimental results demonstrated that the HIL
has a credible potential for this purpose. These experiments were also simulated using the dynamic
kinetic model, which showed good agreement with the experimental findings. However, some
potential improvements to the dynamic kinetic model have been identified to enhance its
compatibility with experimental conditions.Doctor of Philosophy (PhD) in Natural Resources Engineerin
Multi-faith+ architecture: fostering faith and spirituality on the Laurentian University campus
No full textReligious and Spiritual beliefs are more than
shared morals and values, but cosmologies that
enlighten personal truths, goals and faiths.
The development of these cosmologies have
always been essential for the evolution of
respectful, mindful and concerned citizens,
especially in higher education contexts.
However, history reflects that North American
university architecture and programs have not
always aimed to foster various religious and
spiritual world-views, despite the increasing
diversity found on campuses post-WWI. More
importantly, they have not aimed to foster
interfaith and multicultural comprehension.
Thus, this thesis proposes a re-conceptualized
Multi-faith+ Centre at Laurentian University
that seeks to reflect and foster the religiously,
spiritually and culturally rich communities on
campus
Acting as more than just a home for distinct
practices and beliefs of various faiths, this thesis
investigates contemporary case studies and
theoretical frameworks to establish a space that
fosters interfaith acceptance, respect and
understanding on the Laurentian University
campusMaster of Architecture (M.Arch
A greenway forward: revitalizing Ottawa’s core through urban agriculture
No full textOn the surface, the idea of obtaining healthy
produce within an urban setting appears
relatively easy to achieve, however, a variety
of unprecedented challenges present
constraints in realizing this belief. These
constraints are largely due to climate change,
inflation in food prices, population density
increase, and shifts in housing patterns. This
thesis will explore the implementation of
architecture by integrating urban agriculture
within the central experimental farm facility
in Ottawa and how it can become a model
that cultivates and produces economically sustainable food production in cities. Through
extensive literary research, site analysis,
review of case studies, and mapping of
diverse urban areas, it will be expounded that
the implementation of sustainable agriculture
systems within an urban city can facilitate a
healthy environment for the community to
grow. The examination of traditional farming
systems and integration of sustainable
methodologies is the base that will guide this
thesis proposal redefining growing strategies
from rural lands to urban buildings.Master of Architecture (M.Arch
The Collingwood terminals: an adaptive reuse approach to heritage buildings
No full textThis thesis offers a critique that focuses on adaptive reuse for
contemporary architects currently practicing in Ontario. The critique
states the approach of adaptive reuse is interpreted too widely,
resulting in adaptive reuse projects dismissing the original building’s
heritage values. This thesis posits that the architectural community
should reimagine the adaptive reuse approach in consideration of
heritage buildings. This thesis provides an alternative approach to the
practice of adaptive reuse that involves engagement with the existing
building, consisting of historical research and documentation. As well
as a carefully considered program that connects the buildings history
to the current economy and cultural needs. This proposed method
is demonstrated through a study of a historic 1929 grain terminal in
Collingwood, Ontario. The design proposal is for the adaptation into
a spa that connects the Terminal building back to its history of place
while reintegrating it into the new economy of tourism and recreation.Master of Architecture (M.Arch
Investigating the role of hydrogen sulfide in the regulation of glucagon-like peptide-2 secretion and gut physiology
No full textHydrogen sulfide (H2S) is an endogenously produced gasotransmitter which regulates a variety
of physiological processes including hormone regulation. In individuals with Crohn’s disease or
colitis, H2S is elevated. Whether H2S plays a role in gut disease development or protection is not
clear. Glucagon-Like Peptide-2 (GLP-2) is a gut health-promoting peptide hormone produced in
the enteroendocrine L-cells (EECs) located primarily in the distal gastrointestinal (GI) tract. In
the gut, GLP-2 increases cell proliferation, enhances barrier function, and decreases
inflammation. In this study, it is hypothesized that local H2S produced in the distal GI tract and
in EECs can regulate GLP-2 secretion and downstream gut physiology. GLP-2 secretion and gut
physiology was examined in mice lacking the H2S producing enzyme cystathionine gamma-lyase
(CSE). Additionally, H2S production and GLP-2 secretion was examined from mouse
enteroendocrine L-cells (GLUTag). CSE knockout (KO) mice had significantly reduced
intestinal H2S production and claudin-7 expression. In cells, H2S was also produced directly
from EECs which could be partially blocked by CSE inhibitors. When EECs were treated with
H2S donors (NaHS and GYY 4137), the effect on GLP-2 secretion was variable with a slight
suppression with high dose NaHS and no effect with GYY 4137. Finally, when cells were treated
with CSE inhibitor, GLP-2 secretion was significantly reduced. Our work indicates that the EEC
L-cell can produce the gasotransmitter H2S. Adding additional H2S has a variable effect while
inhibiting endogenous production suppresses GLP-2 secretion. These findings suggest that GLP-
2 may play a role in the interplay between H2S and gastric health, which could provide support
for the potential use of H2S drugs in the treatment of GI diseases.Master of Science (MSc) in Biolog
Assessing soil metal concentrations, microbial biomasses and enzymatic activities in aerial limed lands impacted by mining pollution in the City of Greater Sudbury
Get PDFMining pollution in the City of Greater Sudbury led to acid rain and metal contamination of soils, which ultimately caused massive environmental and ecological damage. Soil liming, in addition to tree planting and fertilizing, have been the techniques used to restore these damaged ecosystems. The objective of this study was to assess the effects of aerial liming on pH, and metal contamination microbial biomass and abundance, enzymatic activities. Soil pH was higher in limed sites compared to unlimed at Baby Lake and Wahnapitae sites but not at HWY 80 N site. Organic matter was higher in limed areas compared to reference site only at Baby Lake site. Metal concentrations of iron (Fe) and arsenic (As) were significantly higher at the unlimed sites. Enzyme assays and Phospholipid fatty acid (PLFA) analysis were used to assess three limed soil sites and their adjacent unlimed soils. β-N-acetylglucosaminidase (BG), aryl sulfatase (AS), and glycine aminopeptidase (GAP) activity levels were significantly increased in the limed soils compared to the unlimed soils. Total microbial biomasses, gram negative bacterial, fungal, and eukaryotic biomasses were all increased in the limed soils compared to the unlimed soils. Microbial biomass ratios of gram negative/gram positive, saturated/unsaturated, and mono/poly microorganisms were all significantly increased at the unlimed sites compared to the limed sites, indicating that the unlimed sites are still undergoing environmental stresses.NSERC, Vale, Sudbury Integrated Nickel Operations (Glencore Limited
Speciation of arsenic in freshwater biota
Get PDFArsenic can reach potentially concerning levels in fish and other aquatic biota, but the risk
posed is strongly dependent on the element’s chemical speciation. However, the speciation of
arsenic in biotic samples remains analytically challenging and freshwater fish, in particular, have
not been extensively studied. The limited information available suggests that freshwater fish can
have highly variable arsenic speciation patterns, both within and between populations. Based on
these knowledge gaps, my thesis has two main goals: (1) to assess the current state of knowledge
on arsenic speciation using a systematic literature review and (2) measure arsenic speciation in
biota from boreal lakes to investigate drivers of variation among individual fish and invertebrates.
My literature review focussed on arsenic speciation in freshwater fish muscle. I identified
39 studies that matched predefined criteria for inclusion based on a review of 1096 potential
studies. I found considerable variability in the available literature; although less toxic organic
species of arsenic typically dominated in fish muscle, there were reports of fish with high
concentrations of the most toxic inorganic species. While studies modeling the drivers of this
variation were limited, some suggest that waterbody characteristics, fish size, and trophic ecology
may contribute.
In my field study, I collected and analyzed fish and invertebrates for two common organic
species of arsenic, arsenobetaine (AsB) and dimethylarsinic acid (DMA), in three lakes across a
contamination gradient near Sudbury, Ontario. Concentrations of these arsenic species varied
widely across fish and invertebrates, generally being found at higher concentrations in the most
contaminated system, a lake associated with an abandoned gold mining site. Trophic ecology
appeared to be a primary factor affecting arsenic speciation in aquatic food webs, with both AsB and DMA decreasing in concentration with increasing trophic position, inferred from stable
nitrogen isotope values. To my knowledge, this is the first study to apply stable isotope techniques
to assess how trophic ecology and diet influence arsenic speciation across whole freshwater food
webs; where prior arsenic speciation studies have focused on fish alone and did not observe the
same biodilution effect. I also identified other factors that may influence arsenic speciation. These
included variation in fish size and age, diet, and interactions with co-occurring chemicals (e.g.,
selenium). However, considerable unexplained differences in arsenic species among taxa remains
for further studies to address.
Future avenues for research on arsenic speciation include continued improvements in
analytical techniques and detection levels, deepening our molecular understanding of arsenic
biotransformation and accumulation, broadening toxicological testing of various arsenic species,
and assessing the behaviour of arsenic species across diverse food webs. Additionally, improving
our understanding of arsenic speciation in freshwater environments is essential to accurately assess
risk to consumers or the aquatic biota themselves. A refinement of environmental and human
health risk assessments based on the results found herein and in future studies are warranted.Master of Science (MSc) in Biolog
The green in-between: the future of public spaces in response to increasing heat waves and urban flood risks
No full textDowntown low-income neighbourhoods in large Canadian cities are
disproportionately affected by heat waves and urban flood risks in the
face of climate change. They are ill-equipped to protect residents and
infrastructures from more frequent and severe extreme weather events
due to the predominance of heat-absorbent and impermeable hardscape
surfaces. This affects the well-being and physical and psychological health
of residents. It also has significant economic impacts. Introducing nature inbetween buildings could help better manage heat and water and provide
beautiful outdoor spaces where people can seek heat relief. The thesis
investigates creating a new type of public space in downtown Toronto,
the Urban Forest Park, learning from soft engineering, passive design, and
biophilic design. It aims to offer a beautiful recreational cool microclimate
that becomes a destination for residents and a resilient neighbourhood
infrastructure that manages stormwater and mitigates the urban heat island
effect.Master of Architecture (M.Arch