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Challenges with regenerating chipper debris pads: evaluating seedling performance nine years after planting
Get PDFDebris from in-bush portable chain flail chippers can alter the abiotic
environment factors within the mineral soil. Thus, chipper debris can create an
unsuitable seedbed for seedling growth and survival. In this thesis, jack pine and white
spruce will be planted on fresh chip pads (age=2) and chip pads that had time to
decompose (age=9). Previous research has shown that chipper debris can insulate the
soil, repel or maintain moisture based on the age of debris, and leach toxic material
based on the age of debris. Ensuring that chipper debris pads are regenerating with
merchantable species is important for forest managers to maintain productivity on crown
land
Food security advocacy and activism among post-secondary students: a case study of Lakehead University
Get PDFThis research project is a case study that explores post-secondary student food insecurity
advocacy and activism at one Northern Ontario university. Using a feminist intersectional case
study approach, I examine how the identities of student activists influence their activism and
advocacy on food insecurity on campus. A focus group with four self-identified student activists
was conducted to gain an understanding about their advocacy efforts and activism at Lakehead
University. Additionally, four in-depth interviews were conducted with administrators to help
understand the context of the campus food environment and to understand the issues and
responses from their perspective. Findings suggest that student involvement and experiences
with food activism is connected with student identity. Gender, race, class, and student status (i.e.,
full time or part-time, and domestic or international student) influence student’s ability to take up
food activism and advocacy. Although not a large sample of participants, the student activists at
Lakehead are passionate about food security, they understand that there is a problem with student
poverty, high tuition rates, and settler-colonial legacies. While food activism and advocacy
informed by food justice is the focus of many student-led initiatives, charity approaches continue
to dominate the wider response to post-secondary student food insecurity on this campus.
Although they are challenged by structural barriers to change, student activists develop
belonging through relationships and a shared sense of purpose in advocating for change on
campus which increases their confidence to pursue activism. This thesis offers insights into
student food advocacy and activism on the issue of post-secondary student food insecurity at
Lakehead University
Design and evaluation of a clinical organ-targeted positron emission tomography camera
Get PDFPositron Emission Tomography (PET) is a non-invasive medical imaging technique
which usesradioactive tracers to visualize the metabolic or biochemical function of tissues and
organs. PET imaging aides in the accurate diagnosis and management of disease including
neurodegeneration and cancer. Standard clinical practice uses whole-body (WB) PET
technology which is limited in its ability to detect small lesions due to inadequate spatial
resolution and the need for high radiotracer doses due to low sensitivity. This has prompted
the development of organ-targeted PET, which places limited field-of-view (FOV) detectors
near to an organ for imaging. This approach offers distinct advantages over WB PET, including
improved spatial resolution for lesion detection, greater sensitivity for imaging with lower
radiotracer doses, and contrast recovery capabilities which permit accurate quantification of
radiotracer uptake in small structures. [...
Investigation of capacitor voltage balancing issues in a five-level inverter with multicarrier modulation schemes
Get PDFFive-level inverters are widely used in medium-voltage (MV) wind energy and
electric drive systems. However, the use of a large number of components (including passive
and active components) and complex control methods are the major issues in the existing
inverters. Also, some of the inverters are difficult to control using multicarrier modulation
schemes due to the lack of redundancy switching states. In this research work, a new five-level
inverter is introduced for MV applications. The new inverter requires only flying capacitors
and switching devices and has a low total component count. Also, it requires only a flying
capacitor voltage balancing method to achieve a safe and reliable operation. Hence, the new
inverter is cost-effective and has less control complexity compared with the existing inverter
topologies. The flying capacitor's voltage in the new inverter is analysed with the help of
charge-balance theory and established as a theoretical basis for the capacitor voltage balancing
method. Through this analysis, a simple voltage balancing method is developed. The developed
balancing method is further analyzed with the conventional multicarrier modulation schemes
using MATLAB simulations at different operating scenarios. Also, a modified multicarrier
modulation scheme is introduced to handle the new inverter operation at higher load power
factors. Finally, the performance comparison of the conventional and modified multicarrier
modulation schemes is presented
Modeling the impact of hemlock woolly adelgid under several climate change scenarios
Get PDFThe hemlock woolly adelgid (Adelges tsugae), or HWA, is a species of insect
invasive to eastern North America that has caused significant mortality amongst its
hemlock (Tsuga spp.) hosts. Survivorship and subsequent population expansion of the
HWA is theorized to be limited primarily by minimum winter temperatures. As climate
change reduces the severity and cold periods of winter, the potential for a northward
expansion of the HWA is introduced. This study utilized maximum entropy modeling
(MaxEnt) in conjunction with an iNaturalist citizen-science occurrence dataset via the
Global Biodiversity Information Facility (GBIF) and WorldClim (HadGEM3)
downscaled climate projection data to model habitat suitability for the HWA throughout
eastern hemlock’s (Tsuga canadensis) range. In addition to a historic conditions
baseline, species distribution models were generated using SSP 126, SSP 245, and SSP
585 emissions scenarios for mid-century (2041-2060) and late-century (2081-2100)
climate change scenarios. The results showed that under a low emissions SSP 126
scenario, the HWA will be capable of inhabiting almost the entirety of the eastern
hemlock’s current range by the end of the century. More extreme SSP 245 and SSP 585
warming scenarios resulted in a more rapid northwards shift in suitable habitat,
encompassing the entire range of eastern hemlock by the middle of the century. The
consequences for eastern hemlock are significant, with HWA infestations likely to
become more widespread and severe due to climate change
Effects of the nitrogen deposition on the forest ecosystems: an overview
Get PDFHuman activities exacerbate the production and emission of reactive nitrogen and lead to
the increase and globalization of nitrogen deposition. At present, the interference of
human activities in the global nitrogen cycle has exceeded the boundaries of the safe
operation of the Earth system. High nitrogen deposition has threatened the health and
safety of the ecosystem and has become a hot issue that needs to be clarified and solved
in the process of ecological civilization construction. This review summarizes the impact
of nitrogen deposition on forest ecosystems from the aspects of nitrogen deposition on
forest plants, animals, and microorganisms by referring to the literature on nitrogen
deposition, introduces the corresponding response mechanism, and includes how we
analyze and compare the data (methodology) and clarify what the effects of Nitrogen
deposition on the forest ecosystems, how forest ecosystems respond and acclimate longterm N deposition(results)
Measurement of bimanual coordination in rehabilitation for poststroke individuals: a systematic review
Get PDFA stroke can result in a decreased ability to coordinate the upper limbs, which leads to
difficulty in performing the activities of daily living (ADLs). As a result, upper-extremity
rehabilitation has been frequently implemented to improve impaired bimanual coordination.
Many studies have examined the nature of bimanual coordination during two-handed discrete
tasks such as reaching and grasping in many different populations. Over the past few decades,
much research has been devoted to examining the nature of bimanual coordination. Foundational
research examining bimanual coordination (i.e., inter-limb coordination) and control, has focused
on how different constraints (e.g., task, individual) affect the degree and stability of spatial and
temporal coupling between the end effectors or joints. This was done in the context of different
philosophical paradigms, in the field of motor control and coordination, such as coordinative
structures (Kugler et al., 1980), and synergies (Haken, 1983). However, in rehabilitation studies,
the issue of bimanual coordination, along with the theoretical relevance of the emerging
inferences have not been systematically addressed. Therefore, the first purpose of this project
was to systematically review the methodological approaches used in the literature that examine
changes in coordination and control in those who have had a stroke following upper-limb
rehabilitation that aimed to improve bimanual function. Another objective was to classify these
approaches in regards to their theoretical and conceptual basis. From this, suggestions were made
as to how to potentially enhance the existing approaches to measuring inter-limb coordination
during bimanual rehabilitation. [...
Pray away the gay: mainline Protestant religious leaders’ responses to the conversion therapy ban in Canada
Get PDFThe purpose of this research study was to explore how mainline Protestant religious
leaders are responding to the conversion therapy ban in Canada. In 2021, Bill C-4: An Act to
amend the Criminal Code (conversion therapy) received royal assent and amended the Criminal
Code to ban conversion therapy in Canada. This includes attempts to repress or change an
individual’s sexual identity or gender expression to heterosexual or cisgender (Parliament of
Canada, 2021). Given the religious foundations of conversion therapy (Kinitz et al., 2021) this
study aimed to answer the research question, "How are mainline Protestant religious leaders
responding to the conversion therapy ban in Canada?”. To answer this research question, 12
semi-structured qualitative interviews were completed with religious leaders from the Anglican
Church of Canada and the United Church of Canada currently practicing in the province of
Ontario. These participants were recruited using purposive and snowball sampling methods.
Qualitative data were analyzed using thematic analysis. Participants indicated that they were in
favour of the conversion therapy ban due to their acceptance of the 2SLGBTQ+ community, the
identified strengths of the ban, the harm that conversion therapy causes, and their 2SLGBTQ+
affirming religious beliefs including scripture. Participants expressed concern over the efficacy
and enforcement of the conversion therapy ban and offered suggestions for potential next steps
following the conversion therapy ban. The findings of this research have potential implications
for the literature on conversion therapy, Social Work practice, and mainline Protestant religious
leaders
Historical comparison of tea culture in China, Britain, and Japan between the sixteenth and nineteenth centuries: a performative approach to ritual theory
Get PDFTea culture was transmitted from China, the country of origin, first to Japan and then to Britain.
The former is a tradition steeped in Japanese history, while the latter is more recent and a
function of colonialism and global commerce. While tea (Camellia sinensis) consumption was a
part of everyday life in all three countries, the tea ceremony was also prominent and played
indispensable roles in Chinese, Japanese, and British imperial and colonial national cultures.
This historical comparison of tea cultures in China, Japan, and Britain dating from the sixteenth
to nineteenth centuries first describes the diffusion of tea and the utensils used to consume it. It
then systematically describes and compares the tea ceremonies that developed in these three
nations using ritual theory with a performative approach. The previous research literature
generally only focused on two-country comparisons or on the interpretation of contemporary
distinctions in diverse tea cultures found around the world. The research approach used here
derives from the author’s unique background living in China and Canada, as well as learning in
Japan. This enables a more comprehensive comparison grounded in a historical and cultural
context. Simultaneously, the researcher employs a performative analytic approach using
Tambiah’s ritual definition and characteristics to explore the symbolic transformation of the tea
ceremony as it spread from the host country of China to the recipient countries of Japan and
Britain between the sixteenth to nineteenth centuries
The effects of bilateral ankle bracing and sex on swing block jump height, agility, and sport related anxiety in volleyball players
Get PDFAnkle braces are commonly worn in the athletic community both as a method of
rehabilitation after sustaining an ankle injury, and prophylactically to prevent an injury. Within
court sports such as volleyball, athletes are at a heightened risk of sustaining common and
reoccurring ankle injuries. Research on how ankle braces affect athletic performance variables
such as vertical jump height and agility speed has mixed results, with some studies reporting no
change in performance, while others reporting reductions in performance. With studies citing
factors such as ankle range of motion, muscle activation, and changes in lower body kinematics
as the cause for changes in athletic performance, more research is needed to fully understand this
relationship between bracing and performance. Additionally, differences between sexes has been
proposed on some of these identified factors. Also, it has been shown that after sustaining an
injury, athletes generally experience higher levels of anxiety when returning to sport
participation, with female athletes showing even greater levels of anxiety than males. It has also
been suggested that while using supportive ankle devices, such as athletic tape or ankle braces,
during rehabilitation, athletes then depend on these devices for psychological support even after
their injury has fully healed. As such, the purpose of this study was to examine the effects of
bilateral soft-shell ankle bracing and sex on swing block vertical jump height, normalized ground
reaction force (GRF) in the Z-plane, agility time, and measures of sport related anxiety as
measured by the Sport Anxiety Scale-2 (SAS-2). [...