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Biodiversity loss due to the increase of monoculture lawns
Get PDFLawns have evolved over time, starting as functional spaces in medieval gardens to
appearing as the manicured, European-inspired landscapes we know today. The widespread use
of monoculture lawns in North America signifies a shift towards a curated environment. These
lawns come with consequences for biodiversity due to intensive maintenance like frequent
mowing, chemical treatments, and watering. This study explores the history of lawns, the impact
of maintenance on biodiversity, and potential sustainable lawn care approaches. This thesis
highlights the negative impacts of having monoculture lawns, such as reducing insect
populations, disrupting soil quality, and polluting water ecosystems with chemicals. It
emphasizes the need for society and municipal regulations to shift towards more eco-friendly
lawn management practices. This review stresses the importance of addressing the downsides of
monoculture lawns through proactive measures and exploring sustainable alternatives
Mechanical properties of Black spruce wood subjected to different silvicultural treatments
Get PDFBlack spruce is one of the most common commercial softwoods in Northwestern
Ontario. Its abundance, along with its physical and mechanical properties, make it a very
important species for commercial harvesting. Its physical and mechanical properties
make it suitable for infrastructure and load-bearing purposes, and knowing how these
characteristics can be maximized for the best quality lumber of important. The way trees
are managed while they are growing affects what kind of mechanical properties they end
up with when they are harvested, particularly in regard to thinning levels. This thesis
examines the effects of light and heavy thinning on Black spruce physical and
mechanical properties, and which of the two produces the better properties, particularly
for the purpose of wood quality.
Nine trees were taken from a forest near Beardmore, Ontario, where thinning
treatments were applied. There were three different treatment types in total: light
thinning, heavy thinning, and control. The trees were harvested after 15 years and cut
into sticks, where they were tested for properties, including modulus of elasticity and
modulus of rupture, according to the ASTM standards. The sticks were then cut into
compression and density cubes and tested for compression parallel to grain and density
also according to the corresponding standards. These tests were all done with the sticks
and cubes at 12% moisture content. After the density measurements were taken, the
density cubes were dried in an oven and tested for density again at 0% MC. Data
analysis was done using R studio and results found that light thinning produced the best
physical and mechanical properties consistently compared to the heavy thinning and
control plots
Distributed cooperative state estimation and control for multi-agent autonomous systems
Get PDFThis dissertation addresses several problems related to distributed cooperative state
estimation and control design for multi-agent rigid-body autonomous systems, namely
bearing-based distributed pose estimation, distributed attitude estimation on SO(3), and
global attitude synchronization on SO(3).
We consider the distributed pose estimation problem for multi-agent rigid-body systems, under a directed graph topology, assuming that two agents have access to their
respective poses. First, we consider the case where all agents have static positions and
time-varying orientations, and propose two distributed pose estimation schemes evolving
on SO(3) × R
3 and SO(3) × R
3 × R
3
, with almost global asymptotic stability guarantees. Thereafter, we consider the case where the agents positions and orientations are
time-varying, and propose a distributed pose observer evolving on SO(3)×R
3
, with local
exponential stability guarantees. The three proposed estimation schemes rely on individual angular velocity (and linear velocity in the case of agents with time-varying positions)
measurements and local information exchange between neighboring agents (relative timevarying bearing measurements and estimated poses).
Next, we consider the problem of distributed attitude estimation of multi-agent systems, evolving on SO(3), relying on individual angular velocity and relative attitude
measurements, under an undirected, connected and acyclic communication graph topology. We propose two distributed attitude observers on SO(3); a continuous version and a
hybrid version, endowed respectively with almost global asymptotic stability and global
asymptotic stability guarantees. In addition, the proposed hybrid attitude estimation
scheme is used to solve the pose estimation problem of multi-agent rigid-body systems,
with global asymptotic stability guarantees, relying on individual linear and angular
velocity measurements as well as local relative bearing and relative orientation measurements.
Finally, we propose a distributed hybrid attitude synchronization scheme (with and
without individual velocity measurements) for a group of rigid body systems evolving on
SO(3) under an undirected, connected and acyclic communication graph topology, with
global asymptotic stability guarantees
Effect of different temperatures and pH on the growth and interactions of Hypholoma species and Phlebiopsis gigantea with Armillaria ostoyae and Heterobasidion irregulare
Get PDFRoot and butt rot diseases caused by the fungal pathogens Armillaria ostoyae and
Heterobasidion irregulare, result in substantial economic and ecological losses to pine plantations
across southcentral Ontario, Canada. Biocontrol agents like Hypholoma species and Phlebiopsis
gigantea offer potential solutions for managing these diseases. However, their effectiveness against
these pathogens is highly influenced by key abiotic factors such as temperature and soil pH. I
investigated the impact of temperature and pH on the growth of fungal pathogens A. ostoyae (strains:
B249-28 and P162-7) and He. irregulare, in the presence and absence of biocontrol species and
strains of Hypholoma spp. (Hypholoma fasciculare, Hy. sublateritium, Hy. capnoides) and
Phlebiopsis gigantea.
Single and paired colony in vitro experiments were conducted using 2% malt agar media at 2,
10, 15, 20, 25, and 30°C, and pH levels of 5.0, 6.0, 7.0, and 8.0 to compare and contrast growth
responses in the absence and presence of competition between the pathogens and their respective
biocontrol species and strains. [...
Geochemistry, petrography, geochronology, and radiogenic isotopes of the weakly mineralized intrusions in Thunder Bay North Igneous Complex
Get PDFThe Thunder Bay North Igneous Complex (TBNIC) is located approximately 50 km northeast of Thunder
Bay, Ontario, Canada. It comprises two Cu–Ni–PGE-mineralized mafic–ultramafic intrusions, the Escape
and Current Intrusions, and five smaller mafic–ultramafic intrusions whose mineralization potential has
yet to be fully assessed, namely the Lone Island Lake, Greenwich, Southeast Anomaly (SEA), and 025
intrusions, and the East–West Connector (EWC). The five gabbroic to peridotitic intrusions are the focus
of this study. They are characterized by high magnetic anomalies and crosscut the Archean granitoids and
metasedimentary rocks of the Quetico Subprovince. U-Pb dating yielded an age of 1107.6 ± 0.9 Ma for the
Escape intrusion, which is the oldest date among TBN intrusions, and an age of 1105 ± 0.9 Ma for the
Greenwich intrusion.
Field observations and drill core logging of the five intrusions indicates that they are gabbroic to peridotitic
in composition with approximately 6-9% sulfides. The sulphides are dominantly pyrite, with lesser
amounts of chalcopyrite and pyrrhotite. Petrographic analysis of the five intrusions show them to comprise
gabbronorite with lesser leuco-gabbro, gabbro, and websterites for the Lone Island intrusion, gabbronorite
to websterite and lherzolite for 025, gabbro to websterite for SEA, and highly altered gabbro in the EWC
and Greenwich intrusions. [...
Are the fish safe to eat? An examination of Lake Nipigon fish consumption guidelines through the perspective of Biinjitiwaabik Zaaging Anishinaabek
Get PDFMercury (Hg) is a contaminant of concern when consuming fish from freshwater lakes. It
is known to persist in high concentrations in piscivorous fishes such as Walleye which are
commonly consumed by people. The people from the community of Biinjitiwaabik Zaaging
Anishinaabek (BZA) Rock Bay have harvested fish from the Lake Nipigon basin for millennia and
have observed changes to the Lake, particularly those resulting from resource development and
extraction. Large scale hydroelectric projects and mining have created concerns over the safety of
eating Walleye in the Lake Nipigon basin from traditional fishing locations. While fish
consumption guidelines are posted by the provincial government for certain areas, a lack of robust
data, trust, transparency and communication about the risks of exposure to consumers has rendered
these guidelines largely ineffective for community use. In this study, data collection was led by
community fishermen to collect fish from traditional fishing locations to produce community
driven fish consumption guidelines. In general, fish consumption guidelines produced from
community sampling were less restrictive than those posted by the provincial government where
comparable. However, community-based fish consumption guidelines were more restrictive in
riverine environments than lake sampling locations. As a result of having engaged in data
collection and monitoring for fish contaminants, BZA has developed greater trust and interest in
fish consumption guidelines while greatly enhancing its lands and resources program to further
study concerns on Lake Nipigon
Developing ecologically conscious macro-models embedded in Gandhi’s educational philosophy for Indian K12 Schooling: a Teacher’s handbook
Get PDFThe need for a transformative approach to environmental education has become more pressing as traditional teaching methods often fail to foster deep ecological understanding and sustainable behaviors among students. This handbook was developed to address the disconnect between environmental knowledge and meaningful, action-oriented learning in Indian K-12 education. Drawing on Gandhian educational philosophy, the specific objective of this work is to create immersive, nature-based instructional activities that cultivate ecological consciousness, ecological literacy, and a kinship with nature (ecophily).
This handbook not only emphasizes the importance of integrating nature-based pedagogy into the curriculum but also provides practical instructional activities and guidelines. Thus, ensuring that nature becomes an active participant in the learning process, moving beyond being a mere backdrop to serving as a central element of experiential education. The handbook employs ecological macro-models, which are interactive, experiential representations of natural systems. These models engage students directly, allowing them to experience and internalize ecological processes through embodied learning. The design of these activities aligns with the National Education Policy (NEP 2020) of India and the National Curriculum Framework (NCF) of India, aiming to provide educators with practical tools that overcome challenges like fragmented integration of environmental education and a reliance on rote learning. This work concludes with guidelines and exemplars for incorporating ecological macro-models in the curriculum to foster lifelong environmental stewardship and holistic education
Hyperpolarized xenon-129 chemical exchange saturation transfer (HyperCEST) molecular imaging: achievements and future challenges
Get PDFMolecular magnetic resonance imaging (MRI) is an emerging field that is set to revolutionize our perspective of disease diagnosis, treatment efficacy monitoring, and precision medicine in full concordance with personalized medicine. A wide range of hyperpolarized (HP) 129Xe biosensors have been recently developed, demonstrating their potential applications in molecular settings, and achieving notable success within in vitro studies. The favorable nuclear magnetic resonance properties of 129Xe, coupled with its non-toxic nature, high solubility in biological tissues, and capacity to dissolve in blood and diffuse across membranes, highlight its superior role for applications in molecular MRI settings. The incorporation of reporters that combine signal enhancement from both hyperpolarized 129Xe and chemical exchange saturation transfer holds the potential to address the primary limitation of low sensitivity observed in conventional MRI. This review provides a summary of the various applications of HP 129Xe biosensors developed over the last decade, specifically highlighting their use in MRI. Moreover, this paper addresses the evolution of in vivo applications of HP 129Xe, discussing its potential transition into clinical settings
Unveiling the hidden pandemic: service provider perspectives on the rise in intimate partner violence (IPV) in Northwestern Ontario midst the COVID-19 pandemic
No full textIntimate partner violence (IPV) is a public health concern that can affect
individuals regardless of gender, socioeconomic status, sexual orientation, ethnicity,
and geographic location (Moreira & Pinto da Costa, 2020). However, women are
disproportionately represented in victimization rates worldwide with the World Health
Organization reporting that on average 35% of women - more than one in three women
- have experienced at least one form of physical, psychological and/or sexual violence
perpetrated by an intimate partner throughout their lifetime (Moreira & Pinto da Costa,
2020; UN Women, 2020). Rural, remote and northern (RRN) regions in Canada present
the highest rates of IPV and femicide compared to urban centres, while having limited
availability of IPV services (Moffitt et al., 2022). In times of crisis, IPV cases increase
drastically; this is documented, for example, during Hurricane Katrina and the Ebola
crisis (Meinhart et al., 2021; Schumacher et al., 2010). The COVID-19 pandemic has
followed this trend as the amalgamation of risk factors including heightened stress,
increased rates of substance abuse, economic uncertainty due to loss of employment,
and stay-at-home orders contributed to unfavourable violence-prone domestic
environments across the globe (Kaukinen, 2020; Kofman et al., 2020).
The primary objective of this research is to understand the challenges faced by
IPV service providers and survivors during the COVID-19 pandemic in the context of
Northwestern Ontario (NWO), from service providers’ perspectives. Service providers
were asked to share their perspectives on the following three guiding questions: (1)
What are the unique challenges that service providers and IPV survivors, as understood
by service providers, in NWO have faced due to the implementation of emergency
protocols during the COVID-19 pandemic? (2) How might public policy support IPV
related organizations and the individuals that access their services in times of crisis
such as pandemics? (3) What is needed in the development of inclusive, gendered, and
equitable health policy and emergency protocols in times of crises? Semi-structured,
in-depth interviews were conducted with five IPV service providers located in different
communities across NWO. [...