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Herpetofauna in Rondeau Provincial Park, Ontario, Canada: comments on sample methodology and forest disturbance
Get PDFHabitat selection in herpetofauna in Rondeau Provincial Park (RPP) around roads and
human structures in built areas were described alongside recommendations on cover
board material for their survey. The first objective was to ascertain differences among
captures between cover board types: 1.5-inch (3.8 cm) thick, but smaller, spruce boards
or 0.5-inch (1.3 cm) thick plywood boards. The second objective was to report on
insights on cover board arrangement for maximum captures and appropriate seasons
for herpetological surveys in the RPP region. A third objective was to determine how
distance to nearest road or distance to the nearest artificial structure might influence
captures. Cover boards were classified by type and frequency of capture across eight
common species in RPP. Significantly higher captures than expected by the area from
which all traps were drawing indicated patterns of selection. The period over which peak
captures occurred was plotted for each species against temperature trends over the
2014 season. Species preferring moist habitats were attracted to a more insulating
board that mimics damp microclimates; those preferring dry habitats were ready to use
a less insulating plywood board. Model selection based on Akaike’s Information
Criterion (AIC) for small samples was used to find habitat associations for five species
with sufficient captures in forest and built areas, distance to the nearest road, and
distance to identified buildings in the cottage development. Roads created a significant
apparent deterrent to the herpetofauna in RPP. As the climate changes, herpetofauna
will be forced to change their activity seasons. The trends illustrated in RPP indicated
that small, cryptic species of lizards could survive anthropogenic disturbance and even
find overnight refuge in anthropogenic areas
Evolutive fracture behavior of cemented paste backfill
Get PDFUnderground mining is a key global industry that produces many of the mineral resources needed
by several sectors of the economy. However, underground mining extracts large volumes of
material from below the ground, which not only creates substantial subsurface voids, bult also
produces high volumes of solid waste. Consequently, the potentially catastrophic failure of
underground openings and environmental issues such as acid mine drainage has attracted
increasing attention. To ensure the safety of mining workers and equipment and sustainably reuse
the mine waste materials, cemented paste backfill (CPB, an engineered mixture of tailings,
hydraulic binder, and water) technology has been widely adopted in underground mines around
the world. Since CPB materials are used as the key ground support measure, the mechanical
behaviors and properties play crucial roles in the safe design of CPB under complex field loading
conditions. As a type of cementitious materials, the failure process is governed by the development
of tensile and shear crack in CPB matrix under various loading conditions. Meanwhile, due to the
progression of cement hydration, CPB materials also demonstrate curing time-dependent evolution
of mechanical behaviors and properties. Moreover, a considerable amount of water is utilized to
prepare the CPB paste and thus affects the particle interaction and cement hydration. Therefore, it
is of theoretical and practical importance to investigate the effect of mix recipe and hydraulic
factors on the evolutive fracture behavior and properties of CPB under mode-I (i.e., tensile stress),
mode-II (in-plane shear stress), and mode-III (out-of-plane shear stress) loading conditions at
different curing times. However, previous studies focus mainly on the conventional geomechanical
behaviors, including compressive, tensile, and shear behaviors, of CPB. [...
Predicting pain catastrophizing and hypervigilance among endurance athletes: the interactive roles of perfectionism and sport pain ethic endorsement
Get PDFGenetic variation of functional traits related to drought tolerance in yellow birch seedlings
Get PDFUnderstanding patterns of variation in drought-related traits of hardwood trees is crucial
for conserving and managing North American temperate forests under climate change.
In this study, I examined provenance variation of yellow birch (Betula alleghaniensis
Britton) in traits related to drought resistance. Yellow birch is a widespread and
economically important eastern North American hardwood species. A common garden
approach was used to compare height, diameter, biomass, leaf morphology, and stable
carbon isotopes among ten seed sources originating from across Canada and Northern
US states. Analysis of variance (ANOVA) of seedling height and diameter did not reveal
significant variation in either trait, while ANOVA of a subsample (n=40) revealed
significant variation in height and leaf characters (average horizontal width, horizontal
width, maximum perpendicular width, perpendicular width 1, and perpendicular width
2). Simple linear regressions revealed significant correlations between variation in leaf
morphological traits and climate at seed origin. Temperature-related climate variables
were more strongly correlated with leaf traits than precipitation-related climate
variables. [...
Effect of sulfate content on the evolutive fracture behavior and properties of fiber-reinforced cemented paste backfill
Get PDFBackfilling technology is utilized globally to improve ore recovery, reduce mine-generated waste,
and provide stability to underground voids. Cemented paste backfill (CPB), a mixture of mine
tailings, cement binder, and mixing water is the desired method of backfilling. After filling the
underground space (called a stope), CPB is required to provide ground resistance to the surrounding
rock walls, be used as a roof for continued mining operations, or a floor for underground mine
workers and equipment. A challenge to the use of CPB is the vast quantities of sulfide minerals
such as pyrite and pyrrhotite containing irons present in the waste mine tailings. The sulfate anions
generated from the oxidation of sulfide minerals not only interfere with the progression of cement
hydration but also produce expansive hydration products, including gypsum and ettringite. As a
result, the sulfate anions are able to change the microstructure and macroscale geomechanical
behavior and material properties of the CPB materials. Therefore, it is of theoretical and practical
importance to fully consider sulfate-induced evolution of mechanical behavior and properties of
CPB materials. Moreover, the ability to extract ore up to the CPB pillar provides benefits to the
profitability of the mine. However, mine stopes may reach enormous depthsin excess of 100m into
the earth. Therefore, the CPB is not only subject to the internal chemical effects of the sulfide
minerals but also to the complex loading conditions present within the mine stope. As a type of
brittle material, the failure processes in the CPB matrix are governed by crack propagation under
field loading conditions. Such an event will not only reduce mine profitability but can also
potentially be life-threatening to the underground workers. As a method to mitigate such risk, fiber
reinforcement (FR-CPB) is a promising approach. Hence, it is crucial to systematically investigate
the effect of sulfate solution on the tensile and fracture behavior and properties of fiber-reinforced
CPB materials. [...
Geomechanical behaviour of fibre-reinforced cemented paste backfill under cyclic loading conditions
Get PDFCemented paste backfill (CPB) is considering a promising mine backfilling technology with
several technical, environmental, and economic benefits for the underground mining operation.
After placed into underground voids (termed stopes), the hardened CPB mass is required to
provide reliable ground support to control ground pressure and limit surface subsidence.
However, due to the complex field loading conditions, CPB mass may experience dynamic
loadings induced by mining activities (such as drilling, blasting, and mechanical excavation) and
seismic events. However, as a soft cementitious material, aged CPB is highly brittle in nature and
also featured with poor strain-hardening capabilities, the low tensile strength, and weak post-
peak resistance. As a result, the in-situ CPB mass may undergo catastrophic failure under
complex field dynamic loading condition. This highlights the complexity of loading conditions
in-situ and the need to improve the mechanical stability and performance of CPB. Consequently,
fiber reinforcement has recently attracted increasing attention in the improvement of the
geomechanical behavior and performance of CPB. The benefits of small fiber inclusions on the
mechanical performance of cementitious composites under quasi-static loading conditions and
fiber reinforced cementitious composites (FRCCs) under cyclic loading conditions have been
fairly established by previous researchers. However, there are no studies that have systematically
studied the application of fiber reinforcement in CPB technology under cyclic loading
conditions. The purpose of this thesis research is to study the geomechanical behavior of fiber-
reinforced cemented paste backfill (FR-CPB) under cyclic loading conditions. This body of work
studies the effects of fiber inclusion on the evolutive cyclic compressive and tensile behaviors
and mechanical properties of FR-CPB. Curing time, fiber length and fiber content were used to
study the evolution of FR-CPB’s mechanical properties, including hysteretic energy dissipation,
secant modulus, degraded stress, and damping index. Cyclic stress-strain data reveals that the
geomechanical behavior of FR-CPB is highly influenced by curing time. Aging of FR-CPB
results in a strengthened fiber-bridging effect leading to improvement in composite strength and,
thus, load carrying capacity through full realization of the cement hydration process. [...
Enhancing machine vision using human cognition from EEG analysis
Get PDFVisual classification is the perceptible/computational effort of arranging objects and visual
contexts into distinct labels. Humans and machines have mastered this advanced problem in
their own varied contexts. However, certain aspects inherent to the variability of the visual
stimuli present need to be overcome. This thesis analyses the different dimensions of visual
classification using a combination of human cognition and machine vision. Thus, it presents
novel approaches to joint multimodal learning for machine-learnt visual features and features
learnt using brain-visual embeddings via EEG.
First, the thesis proposes a pipeline structure of grayscale image-based encoding of brainevoked EEG signals as a spatio-temporal feature for improved data convergence. This encoding results in a new benchmark performance of 70% accuracy in multiclass EEG-based
classification (40 classes, a challenging benchmark EEG-ImageNet dataset) due to the inclusion of a stretched spatial space that accommodates all the responses of visual stimuli in a
single visual sample. As a second contribution, it develops a new approach for cross-modal
deep learning based on the concept of model concatenation. This unique model uses a mixed
input of deep features from the image and brain-evoked EEG data encoded with a grayscale
image encoding scheme. [...
Assessment using TerrSet geovisualisation of the temporal and spatial effectiveness of the prescribed burn program in re-establishing the oak savannah habitat at the Pinery Provincial Park
Get PDFOak savannah is a plant community of widely spaced deciduous trees with a
canopy cover of between 25 to 35%, allowing grasses and other ground cover vegetation
to thrive, providing habitats for numerous plant and animal species, including many
endangered species. Historically, oak savannah covered large areas across North
America but only 1% of these habitats still remain. Today, almost half of the oak
savannah habitat in North America is found at the Pinery Provincial Park in Southern
Ontario, but this has been threatened due to fire suppression, overgrazing and pine
planting. Programs have been developed to re-establish the oak savannah at the Pinery,
using a combination of deer population control, pine removal and prescribed burns. This
thesis uses field observations together with TerrSet geovisualisation tools, satellite
photographic records, and field mapping data to assess the temporal and spatial
effectiveness of the programs to re-establish the oak savannah at the Pinery, and it
makes future projections out to 2032. The results indicate that the oak savannah at the
Pinery has been recovering since 2007, but forward projection indicates this may decline
by 2032 unless a more intensive and frequent program of prescribed burns is adopted
Holistic resource management in UAV-assisted wireless networks
Get PDFUnmanned aerial vehicles (UAVs) are considered as a promising solution to assist terrestrial networks in future wireless networks (i.e., beyond fifth-generation (B5G) and sixth-generation (6G)).
The convergence of various technologies requires future wireless networks to provide multiple
functionalities, including communication, computing, control, and caching (4C), necessary for
applications such as connected robotics and autonomous systems. The majority of existing works
consider the developments in 4C individually, which limits the cooperation among 4C for potential
gains. UAVs have been recently introduced to supplement mobile edge computing (MEC) in terrestrial networks to reduce network latency by providing mobile resources at the network edge in
future wireless networks. However, compared to ground base stations (BSs), the limited resources
at the network edge call for holistic management of the resources, which requires joint optimization. We provide a comprehensive review of holistic resource management in UAV-assisted wireless networks. Integrated resource management considers the challenges associated with aerial
networks (such as three-dimensional (3D) placement of UAVs, trajectory planning, channel modelling, and backhaul connectivity) and terrestrial networks (such as limited bandwidth, power, and
interference). We present architectures (source-UAV-destination and UAV-destination architecture)
and 4C in UAV-assisted wireless networks. We then provide a detailed discussion on resource
management by categorizing the optimization problems into individual or combinations of two
(communication and computation) or three (communication, computation and control). Moreover,
solution approaches and performance metrics are discussed and analyzed for different objectives
and problem types. We formulate a mathematical framework for holistic resource management
to minimize the linear combination of network latency and cost for user association while guaranteeing the offloading, computing, and caching constraints. Binary decision variables are used
to allocate offloading and computing resources. Since the decision variables are binary and constraints are linear, the formulated problem is a binary linear programming problem. We propose
a heuristic algorithm based on the interior point method by exploiting the optimization structure
of the problem to get a sub-optimal solution with less complexity. Simulation results show the effectiveness of the proposed work when compared to the optimal results obtained using branch and
bound. Finally, we discuss insight into the potential future research areas to address the challenges
of holistic resource management in UAV-assisted wireless networks
Evaluation of Anti-E6 Single Domain Antibodies for the Treatment of Human Papillomavirus-related Cancer
No full textThe HPV16 genome encodes two oncoproteins, E6 and E7, which are essential for viral
carcinogenesis. While E7 promotes cell proliferation, E6 abolishes the resulting p53-dependent
apoptotic response. We hypothesized that antibodies targeting the E6 protein will allow for p53
restoration and induce apoptosis of the infected cells. Our lab has previously generated a pool of
20 Camelidae-derived single-domain antibodies (VHHs) against the E6 protein (Togtema et al.
2019). VHHs have several properties making them well-suited for therapeutic purposes including
low immunogenicity, high stability, and capacity to bind epitopes not accessible to any other type
of antibody. In the current project, we used dot blots to evaluate the VHHs binding potential to
various recombinant E6 proteins, identifying several successful VHH candidates. Co-
immunoprecipitation using Affigel resin was used to confirm the VHH’s endogenous E6 binding
capacity in CaSki cells. Therein, two clones, C26 and A37, were identified as efficient E6 binders,
in triplicate. Interestingly, in denaturing Western Blot analyses, C26 was found to react with the
maltose-binding protein (MBP)-containing proteins but not with E6 6C/6S lacking an MBP tag,
supporting the hypothesis that C26 binds MBP or E6 through different parts of the antibody. To
deliver the VHHs to target cells, cationic lipid-based protein transfection proved inadequate,
however mRNA transfection resulted in improved transfection efficiency. Functional assays,
including proliferation assays to assess cell proliferation, and immunodetection of p53 and PARP-
1 cleavage following mRNA transfection, were used to evaluate the VHH’s therapeutic potential.
Our results indicate that further optimization of our molecules will be needed to yield VHHs with
therapeutic potential, however, our methodology may serve as a template for other researchers,
creating a pipeline of analysis for the evaluation of antibodies against the E6 protein