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Metapopulation viability analyses of woodland caribou in the Lake Superior range
Get PDFWoodland caribou populations in the Lake Superior range have deteriorated. The
caribou’s decline follows industry growth since the 1900s. Islands like those in Slate
Islands Provincial Park, Michipicoten Island and Caribou Island offer periods of escape
from wolves, the main predators of caribou. Minute mainland populations exist because
of translocations conducted in the early 1980s and late 2010s with A.T. Bergerud, and
later Gord Eason at the head. Together with the island populations, the safest and most
common areas of translocations, the mainland connects what can be considered a
metapopulation. Population viability analyses (PVAs), run on Vortex10, were conducted
to determine ways of creating a stable metapopulation with consideration given to future
arrivals of wolves and future translocations to the Lake Superior islands. The probability
of icing events for caribou dispersion were factored into the PVAs. Wolf appearance on
islands has been the chronic limiting factor of caribou abundance. Allowing no
translocations created a high probability of functional extinction. Specific translocation
starting in the present and continuing until 10 years created the highest likelihood of
persistence of the metapopulation. The Slate, Michipicoten, and Caribou islands are
crucial to metapopulation persistence. Further recovery of the woodland caribou
populations in the Lake Superior range should view translocations as a beneficial
management approach
The effects of stratification methods on paper birch and yellow birch seed germination
Get PDFThis study examines the use of both a typical cold moist stratification method,
and an alternative in their ability to affect germination rates in paper birch (Betula
papyrifera) and yellow birch (Betula alleghaniensis). This alternative method entails the
freezing and thawing of seeds every second day, while the standard method entails only
a single freezing period. Both stratification methods and the experimental control (no
stratification) were subjected to a month-long treatment period before germination tests
were carried out. The alternative stratification method used in this study performed more
poorly than the control, suggesting that freeze-thaw cycles may negatively affect
germination of both yellow and paper birch, with germination tests resulting in 1.54%
germination in paper birch, and 0.00% germination in yellow birch over a month-long trial
period. The traditional method was beneficial to germination in both species, resulting in
67.69% germination for paper birch, and 36.00% germination for yellow birch over a
month-long trial period
Impacts of mountain pine beetles on forest management and succession
Get PDFThe mountain pine beetle has been an ongoing issue in large forest landscapes
for decades and has continued to create issues revolving around forest management and
succession. This thesis will go into depth on the intensity and devastation the mountain
pine beetle has caused in North American forests, and how different forest management
schemes are in the works on how to properly manage massive outbreaks of the mountain
pine beetle.
Findings of the mountain pine beetle traveling northeast and its attack on the jack
pine species have been causing concerns about adjustments to management strategies
and future successional trajectories
The effects of sex, menstrual cycle phase, and hormonal contraceptives on inhibitory control
Get PDFInhibitory control is a major aspect of executive functioning, and ovarian hormones (e.g.,
progesterone and estrogen) have been found to affect processes related to inhibitory control. This
was the first study to examine the effects of sex, menstrual cycle phase (follicular, luteal), and
oral contraceptives (OC) (users, nonusers) on four different types of inhibition (response
inhibition, deferred gratification, reversal learning, and emotional reactivity) across two studies.
The first study examined self-reported inhibitory control in 372 participants at two time points
two-weeks apart. The second study (N = 162) compared groups on several laboratory tasks of
inhibitory control that were given after three mood primes (sad, happy, fear). Group differences
(sex, cycle phase, OC use) were examined. Women showed: (a) higher negative emotional
reactivity than men across self-report and laboratory measures, including relatively higher
accuracy with negative than positive self-associations when sad; (b) more errors of commission
than men on a GoNogo task after sad and fear mood induction; and (c) more problems with self-reported perseverative thinking than men. No sex differences were found for self-report
measures of response inhibition; or any measures of deferred gratification. Regarding cycle
phase effects, follicular phase women had more errors of commission than luteal phase women
after fear mood induction, and this follicular phase effect explained the sex difference. Cycle
effects were not found for reversal learning, emotional reactivity, or self-report measures of
response inhibition. Also, no cycle effects were found for deferred gratification. There was no
evidence that OC users and non-users differed on any of the four types of inhibitory control
either on self-report or lab measures, suggesting no effects of OCs. Findings are discussed in
terms of understanding the role of endogenous and exogenous hormones in inhibitory control
The influence of temperature on dynamic membrane structure
Get PDFThis study investigates the influences of cold source-water temperatures and warm
temperature recoveries on the dynamic changes of membrane structure. The morphology of
membrane pores on the membrane surface was firstly compared through SEM images. The visual
comparisons of the images show that the shrinkage of membrane pores occurred in the cold-water
(0.3, 5, 10°C) treatments and could then be recovered in the warm-water (room temperature and
35°C) remediation. Furthermore, the dynamic changes in membrane pore sizes during cold
temperature and recovery treatments were illustrated by the percentile membrane diameters —
d10, d50 and d90. The membrane pore sizes in cold-water treatment at 0.3°C shrank faster and
were smaller than those of 5 and 10°C. The recovery treatment at 35°C, which fully recovered the
membrane pore sizes to those of virgin membrane, was much more effective than room
temperature treatment. Room temperature recovery only restored the membrane pores close but
not exceeding the original sizes under tested conditions. Both cold temperature treatments and
warm water recoveries stabilized the membrane pore sizes after around 24 hours. Finally,
membrane structure changes over time have been modelled. It implied that warm water cleaning
could retrieve the membrane structure losses affected by cold source water
Low CO2 methanol by methane pyrolysis in catalytic liquid metal bubble reactor
Get PDFMethanol production based on methane pyrolysis presents an opportunity for CO2 utilization
and lower CO2 emissions than traditional methanol production processes that are based on
methane reforming. This research employs a coupled hydrodynamic and kinetic pyrolysis
reactor model in the design and simulation of a methanol plant that produces 2000 t/d of grade
A methanol by direct hydrogenation of CO2. The methane pyrolysis occurs in a catalytic liquid
metal bubble reactor where natural gas is injected at the bottom of the liquid metal bath and
forms bubbles that rise through the molten metal. Methane pyrolysis occurs non catalytically
inside the bubbles and catalytically at the gas-liquid interface. Solid carbon separates from the
molten metal and forms a layer on top of the molten salt cap that is on top of the molten metal
and is used to limit molten metal losses. The solid carbon can be continuously removed via
skimming. A fired heater and heat recovery section are used to satisfy the energy demands of
the process. Because the advantage of methanol synthesis based on methane pyrolysis lies in
its low CO2 emissions, a comprehensive CO2 accounting is performed which accounts for the
plant direct CO2 emissions as well as the indirect CO2 emissions associated with the natural gas
supply chain and the capture of the process CO2 feed. The calculated CO2 emissions are
compared to literature values for other methanol production processes based on methane
reforming or methane pyrolysis. The plant economics are assessed to determine the levelized
cost of carbon and evaluate the economic viability of the novel process. The proposed process
has cradle-to-gate and cradle-to-grave emissions of 0.074 and 1.448 t CO2-eq/t MeOH,
respectively, when a CH4 conversion of 80% in the pyrolysis reactor is used and when the
indirect CO2 emissions are calculated at their base values. The corresponding volume of
Cu0.45Bi0.55 catalytic liquid metal is 98.0 m3
. These operating conditions result in a levelized cost
of carbon of $270/t. It was found that the levelized cost of carbon is most sensitive to the fixed
capital investment of the plant and the purchase price of CO2. This work shows that the source
of CO2 is a critical variable for this process, as it affects both the purchase price and the
emissions associated with its capture
The role of emotions in generating and sustaining climate action for youth climate champions: an exploratory study in Northern Ontario
Get PDFAnthropogenic climate change is a wicked problem resulting in complex and
compounding health impacts at multiple scales and across timelines. While there is a solid base
of empirical evidence documenting the physical health impacts of climate change, less is known
about the mental, emotional, and spiritual dimensions of maturing in a climate-altered world,
where extreme events and doom-and-gloom messaging are increasingly prevalent. Despite
contributing little to rising greenhouse gas emissions, young people are at heightened risk of
experiencing mental and emotional health impacts of the climate crisis because they are at a
critical stage of physical and psychological development, and because adverse childhood events
have a strong impact on mental health into adulthood. Qualitative research exploring the lived
experiences of youth across diverse places is underrepresented in the literature. This thesis
explores the ways in which youth climate champions in Northern Ontario, Canada, are
experiencing the mental and emotional dimensions of the climate emergency and explores the
emotions, supports, and experiences by which they are motivated to engage in climate action.
Through purposeful sampling, 12 young people ages 15-24 across six communities participated
in both semi-structured interviews and asynchronous letter writing to explore their emotional
response to climate change and climate action. Thematic network analysis revealed three global
themes, including making meaning of climate change, climate emotions, and motivations and
supports for youth climate action, supported by 11 organizing themes and illustrated through 31
basic themes. The findings of this research suggest that youth climate champions in Northern
Ontario are experiencing a constellation of climate emotions which are both problematic,
negatively impacting their mental, emotional, and spiritual wellbeing, and generative, motivating
engagement in climate action. These findings indicate that swift, transformative action to
mitigate the climate crisis is the foremost way to protect the mental, emotional, and spiritual
health of young people in the face of climate breakdown. Simultaneously, this study suggests the
need for policy and practice in health and education spaces to support and fund accessible, safe
spaces for young people to come together to recognize, share, and explore the emotional
dimensions of climate change and climate injustice and to create pathways for young people and
allied adults to engage in community-based collective climate action
Driver and landscape-related factors associated with reported wildlife-vehicle collisions in Thunder Bay, Ontario
Get PDFThe ever-expanding road network in Ontario has created serious implications for wildlife
and their movement within the province. This has led to the discovery of many factors that have
the potential to increase the risk of wildlife-vehicle collisions related to both deer and driver
behaviours. White tailed-deer are the most abundant ungulate species in Ontario, leading them to
be involved in a large portion of wildlife-vehicle collisions. Deer-vehicle collisions (DVCs) have
been a cause of concern for decades due to human and deer injury or death and cost of vehicle
damage. In this study, Ministry of Transportation Ontario (MTO) data for wildlife-vehicle
collisions around Thunder Bay, Ontario from 2011-2021 was spatially analyzed using Quantum
Geographic Information System (QGIS). The spatial relationships between DVCs and Ontario
land cover class (LCC), nearby streams, and posted speed limit were considered. Tests of
association displayed a strong relationship between DVCs and LCC. The development class had
the largest positive association, while the disturbed forest class had the largest negative
association. Contrary to other findings, streams were rarely associated with DVCs and the posted
speed limit analysis showed no significant relationship with the spatial distribution of DVCs. It
was concluded that deer behaviour is more influential in the occurrence of DVCs than is driver
behaviour, due to the relationships established between DVCs and deer habitat. Although driver
behaviour such as speeding or distraction may increase risk, collisions cannot occur where deer
are not present. However, mitigation strategies should be targeted at modifying driver behaviour
since such strategies are more economically feasible, effective, and accepted by society than are
options for posting or controlling deer movements
The effect of motivational interviewing training on knowledge, attitude, self-efficacy, subjective norm, and intent to use by undergraduate nurses to support people with substance use: a comparison of two learning styles
Get PDFMental health and well-being are a worldwide concern, especially in the last couple of
years. From late 2020 to early 2022, high self-rated mental health decreased in Canadians aged 12
or older from 64% to 58% (Statistics Canada, 2022). Also, it was found that 25% of Canadians (18
or above) were found positive on at least one of depression, anxiety, or post-traumatic stress
disorder in spring 2021, compared to 21% in fall 2020 (Statistics Canada, 2021). This indicates a
serious problem and a need for immediate interventions. Moreover, the close relationship between
MHD and substance use disorders (SUD) was highlighted during the COVID-19 pandemic. One
in three Canadians with MHDs who also drink alcohol reported an increase of their drinking to
problematic levels (Mental Health Commission of Canada & Canadian Centre on Substance Use,
2020). Similarly, the prevalence of problematic alcohol use in 2021 was found to be 21% among
the general population and 39% among the low income population, compared to 38% and 52% of
problematic cannabis use, respectively (Canadian Centre on Substance Use & Canadian Centre on
Substance Use, 2021). SUDs have many harmful consequences on health and quality of life, like
road traffic accidents, domestic violence, child abuse, and various health problems (McLellan,
2017). A SUD-related crisis is one of the most common issues managed in the emergency
department; approximately 20% of emergency department cases involve substance use (Brubacher
et al., 2008). Northwestern Ontario, including Thunder Bay, has a high proportion of SUD-related
health problems, which puts a higher burden on the health care system (TBDHU, 2017).
Consequently, SUDs are also commonly found in the psychiatric and critical care wards, in
addition to the emergency department (personal communication with Thunder Bay Regional
Hospital’s nurses). [...
Human-crocodile conflict in Timor-Leste: attack characteristics and management implications
Get PDFTimor-Leste is a relatively new developing nation, having gained its
independence from Indonesia in 2002. The people of this country have a traditional
belief system in which the saltwater crocodile, Crocodylus porosus, forms the basis of
their creation myth and thus holds great cultural value. As the populations of both
humans and crocodiles on the island grow, there have been increasing occurrences of
human-crocodile conflict (HCC) throughout the country. Due to the unique situation in
Timor-Leste, normal management practices for HCC are not directly applicable. As a
result, this country requires specific considerations for dealing with this problem while
remaining sensitive to cultural values. This paper aims to discuss characteristics of
human-crocodile conflict in Timor-Leste and recommend strategies for management.
Conflict records from 2007-2021 were collected from the online database, CrocBITE,
and attack characteristics and locations were analysed. Areas of concern due to high
conflict rates are Tutuala and Lake Ira Lalaro of Lautem municipality, Suai of Cova
Lima municipality, and Viqueque of Viqueque municipality. Attack hotspots followed
core crocodile habitat distribution. Analysis of conflict characteristics determined that
males (84%), subsistence fishers (73%) and youth below the age of 20 (43%) were the
people most at risk of attack, with most conflicts (70%) resulting in a fatality. Age,
activity, and water body had many cases in which these characteristics were unknown,
with 32, 23, and 16 respectively. Most incidents occurred at ocean or beaches (32%),
although incidents in rivers (23%) and lakes or ponds (23%) were common. Incidents
peaked in the months of October to April, the warmer and wetter months, in accordance
with crocodile activity levels. Crocodile size information was unavailable for most
cases. Using information analysed here and existing literature, recommendations to help
solve this problem were made, such as the use of traditional knowledge and education,
establishment of economic incentives, genetic and migration pattern studies, and the
integration of the traditional management system, Tara Bandu