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Geographic variation in skull morphology of the wolf (Canis lupus) in relation to prey size across North America
No full textThe wolf (Canis lupus) is the largest member of the dog family, the most widely distributed nonhuman land mammal, and one of the most studied creatures on Earth. Vast amounts of knowledge
about wolf ecology, life history, anatomy, and physiology have been gathered over the decades,
and research into the taxonomic status of its many geographically diverse populations, based
largely on cranial and body morphology, has received much attention. However, the relationship
the wolf shares with its prey, specifically in terms of how the morphology of its skull is affected
by, or related to, its prey in a naturally selective context, has received far less attention.
In my attempt to determine the character of this relationship and its likely causes, I employ
in this study a multivariate statistical approach using a total of 23 linear measurements taken from
the crania, teeth, and jaws/mandibles of 583 museum-curated North American wolves (333 males,
250 females), harvested between 1894 and 2009 from 17 geographic regions. Specimen harvest
locations include the arctic, northwestern, and central provinces/territories of Canada; mainland
Alaska-Yukon, and the Alexander Archipelago; northern and south-central Ontario, and New
Mexico. Only adult skulls were sampled, and specimens were determined to be adults by
examining the closure of the basisphenoid suture, presence of mature dentition, and developed
postorbital processes and sagittal crests. A geographically varying index of mean pooled prey
weight (MPPW) was developed through literature review against which variables reflecting skull
size and shape would be compared.
Wolves are sexually dimorphic, with males appearing significantly larger on average than
females in all linear skull measurements. A 5-Factor Principal Component Analysis (PCA)
revealed that PC 1 accounted for ~76.5% of the observable variation in male and female data, and
that the overall size of any skull, male or female, is best represented primarily by its condylobasal
and jaw lengths (CBL, JL) and secondarily by its zygomatic width (Zyg B). A factor value (F1
Score) associated with PC 1 was ascribed to skulls, and this value equates with its greatest length
(GSL; premaxilla to sagittal crest). The largest specimens hailed from mainland Alaska-Yukon,
the Rocky Mountains, Wood Buffalo National Park, and central Saskatchewan. Moderately sized
skulls were from arctic and northwestern Canada, the Alexander Archipelago, and northern
Ontario. The smallest skulls were from south-central Ontario and New Mexico. Linear regression indicated significantly positive relationships for wolves of both sexes
between MPPW and F1 Score, GSL, and Zyg B. When 17 sampling regions are reduced to 13, by
combining geographically contiguous regions which display non-differences in average skull size,
biome/climate characteristics, and prey base assemblages, these relationships are strengthened.
These relationships, especially MPPW and Zyg B, are also stronger for males, suggesting that
males are better adapted than females for hunting and killing large prey. Skull size is also
significantly positively related to prey species richness, suggesting that greater availabilities of
food help to maximize growth potentials in wolves. This may be why Alexander Archipelago
wolves, which seasonally prey upon salmon, are larger than predicted given a diet consisting
primarily of small deer. It may also help explain why Rocky Mountain wolves, living in a region
inhabited by 6 or 7 large prey species, are the largest on average of any other region.
For 13 sampling regions, I calculated the average bite forces (BFs) of wolves at the
mandibular canine (BFC) and the first mandibular molar (BFM) using 3D digital modelling
techniques and the ‘dry skull method’ developed by Thomason (1991). BFs were significantly
positively related to MPPW, and this relationship was stronger for females. This may be due to
greater natural variance in males; it may also suggest that females are adapted to process flesh with
greater efficiency before ingestion, possibly a consequence of nutritional requirements associated
with reproduction. BFs are most strongly associated with the size of the jaw muscles, which are
intricately linked to Zyg B. The relationships between BFs and Zyg B is stronger than the
relationships between MPPW and BFs, indicating that prey size only indirectly influences bite
force via skull morphology. This study determines the presence of links between prey size, prey availability, and skull
size in wolves, and is the first to distinguish between sex and among geographic regions in
estimating their bite forces. This study would benefit from (1) additional skulls from specific
regions and (2) data on regional prey densities to compare against skull sizes. Future research may
involve genetic analyses to examine if regional differences in wolf skull morphology are also
reflected by genotype, and isotope analyses to better characterize the regional diets of
geographically diverse wolf populations
Single shot detector for object detection using an ensemble of deep learning and statistical modelling for robot learning applications
No full textIn this study, a deep learning model was synthesized for object detection that can give better
results than the state-of-the-art accuracy and reliability in production environments making it
more accessible to production-ready applications. For this, a model architecture was used
that is inspired by state-of-the-art Single Shot Detector architecture. Statistical analysis was
performed on the results generated by the model to make final predictions in each frame.
Experimental results outperform simple-SSD architecture. For 300 X 300 inputs, it achieves
84.7% mean Average Precision on the system with Nvidia GeForce GTX 1660 Ti 14GB, 16
GB ram, and Intel(R) Core (TM) i7-9750H CPU @ 2.60GHz at 60FPS, outperforming
existing architectures of SSD, Faster Region - Convolutional Neural Network, You Only Look
Once (YOLO), Resnet50, Resnet100 in use
Preliminary findings of assessing NOSM's social accountability toward Northern & rural Francophone communities
No full textThe Northern Ontario School of Medicine (NOSM) was founded in 2003 with a specific
mandate to improve the health of the people and communities of Northern Ontario. The objective
of this project was to determine whether NOSM was remaining socially accountable to the
healthcare needs of Francophones in Northern Ontario by: (i) graduating physicians capable of
offering French language services, and (ii) identifying whether these physicians are locating their
practice in areas of greatest need for such services. Specifically, if NOSM learners’ who reported
having French as a language of competence at entry to, and exit from, medical school located their
practices in areas densely populated by Francophones in Northern Ontario. To do so, three data
sources were utilized; a) the Centre for Rural and Northern Health Research Tracking Study data
of NOSM learners; b) the College of Physicians and Surgeons of Ontario (CPSO) public “Find a
Doctor” search; and c) the 2016 Statistics Canada Census data. Laurentian University Research
Ethics Board approval was obtained for this project. In this project, I found that 39% and 38% of
learners identified French competency in the entry and exit tracking survey respectively. Of the
French respondents identified in the tracking surveys, 20% and 21% identified French competency
in practice (CPSO registry). A total of 70% of NOSM French-competent graduates were currently
practising in a Francophone community in Ontario (i.e., total population having ≥ 10% of
Francophones), with ~92% of French-competent respondents having located their practice in a
French community in the north (having a postal code beginning with P). These preliminary results
suggest that NOSM is achieving its mission of social accountability towards Francophones in
northern Ontario and more specifically, that NOSM is helping to improving the availability of
French language medical services for Francophones in Ontario.Master of Human Kinetics (MHK
Building agriculture: an architectural investigation of a new urban farm type to establish food sovereignty In Regent Park, Toronto
No full text1 in 8 households in Canada do not have adequate access to healthy and affordable food1 Across the country this issue is even more prevalent in urban centers compared to rural areas2
.Considering that by 2050, it is estimated that 68% of the world’s population will live in cities, more
needs to be done in order to ensure proper production, distribution and disposal of food in and around
cities as they continue to expand3
. A strong interest in sustainability has brought this topic to light
because food is something that connects everyone, and the food industry has significant health, social,
and environmental impacts throughout communities around the world. Today, the food network is a
global system, leaving behind past traditions of locally grown food, which supported local farmers, and
the local economy. This has resulted in a disconnect between producers and consumers, and a lack
of equity in the food system. As a result, the issue of food sovereignty is the driving factor behind this
thesis proposal; and more specifically how the integration of architecture and agriculture can begin to
establish food sovereignty in an urban environment through the introduction of an urban farm that can
grow food all year round utilizing sustainable practices.
The thesis research will look at current issues with the food network, and examine urban
agriculture case studies around the world, within Canada, and in the city of Toronto. Toronto was
chosen as the urban context for the project because it is one of the most advanced cities globally in
regards to urban agriculture initiatives, and the cold climate presents challenges that very few projects
globally have dealt with. More specifically, the thesis will look at Regent Park in Toronto’s East end,
a neighbourhood that has undergone significant development over the past decade. Regent Park
has a history of food sovereignty which began in the mid 1800’s when the area was known as South
Cabbagetown, due to the Irish immigrants who grew cabbages and other vegetables on their front lawns for food4 The architectural solution proposed will be an urban farm that prioritizes education in
association with other community led program; looking at the food system in a holistic way in order
to establish a closed loop food system. The thesis aims to establish a solution that not only transforms
the chosen site, but a solution that can begin to influence different areas by setting out principles that
re-imagine how the city and others around the world can use design in order to better integrate food sovereignty within urban environments
Identifying the anti-inflammatory potential of α7 nicotinic receptor silent agonists in human blood immune cells
Get PDFThe recent development of α7 nAChR specific molecules, referred to as silent
agonists, elicit prolonged channel closing with minimal channel activation and are
thought to provoke unique nAChR-dependent metabotropic signaling cascades. This
study assessed the anti-inflammatory potential of several silent agonists in modulating
lipopolysaccharide (LPS)-induced immune responses in human blood immune cells.
Fresh whole blood from healthy volunteers was pre-treated at different time points with
silent agonists followed by a 24hr LPS stimulation. Cytometric bead arrays (CBAs) were
used to quantify the levels of cytokines IL-1β, IL-6, IL-10, IL-12, and TNF-α in sample
supernatants. Then, BioPlex phosphoprotein kits were used to measure phosphorylation
levels of various signaling pathway proteins (NF-kB, Akt, ERK1/2, STAT1, and
STAT3). For this experiment, peripheral blood mononuclear cells (PBMC) and
monocytes isolated from PBMCs were treated with a silent agonist during the LPS
stimulation (15-120min). Finally, cell phenotyping studies were carried out in PBMC
cultures treated with silent agonists and stimulated with LPS (48hrs). The markers CD14,
CD16, CCR2, CD36, CD11c, and HLA-DR were studied. We report that the silent
agonist pCF3 diEPP significantly downregulated the secretion of pro-inflammatory
cytokines and phosphorylation of signaling proteins. We did not observe any significant
findings with our cell phenotype studies. Overall, our data show that silent agonists
modulate LPS-induced release of pro-inflammatory cytokines and signaling events in
human peripheral blood immune cells. Silent agonists selective for α7 nAChRs may thus
offer a new therapeutic strategy for the treatment of inflammatory diseases.Master of Science (MSc) in Biolog
The mineralogy, geochemistry and microbiology of Cobalt-bearing mine tailings from the Cobalt Mining Camp in Northeastern Ontario, Canada
No full textAdvancements in the field of biotechnology have proven bioleaching processes as an economic
and environmentally safe form of mining. Most bioleaching studies to date however have been
focused on Fe, Cu, and Au-sulfidic mine tailings, rather than metalloid-rich, neutral-pH tailings.
This thesis will apply a multidisciplinary and multi-variate statistical approach to explore
whether the neutral, Co and As-rich tailings material within the Cobalt mining camp can be
efficiently bioleached. Tailings material within 30-cm depth profiles from three tailings sites
(sites A, B and C) were characterized for their mineralogical, chemical and microbial community
compositions, followed by the execution of bench-scale oxidative and reductive bioleaching
experiments. Tailings material from sites A, B and C are composed primarily of quartz, albite,
clinochlore, calcite and dolomite with minor safflorite, arsenopyrite, erythrite and annabergite.
The material at site A contains on average more (sulf-)arsenides and higher concentrations of Fe
than site B. Site C however is altogether geochemically and mineralogically dissimilar, with the
presence of distinct reduced and oxidized zones. Variations in the Co+As+Sb+Zn (Co#), Fe
(Fe#), and total S (S#) have been identified as geochemical markers for the presence of Fe, Coarsenides versus secondary Co, Ni, Zn-arsenates, e.g. tailings material with a high Co# and low
Fe# tend to have a higher proportion of secondary arsenate minerals. In the tailings material of
sites B and C, a lower average As valence coincides with a higher S#. Three distinct site-specific
groupings are observed for 1) the Co vs Fe and S#’s and 2) the microbial communities. The
Cobalt tailings are primarily composed of Actinobacteria and Proteobacteria and N, S, Fe,
methane, and (possible) As-cycling bacteria. The tailings from sites B and C have a larger
abundance of Fe- and S-cycling bacteria (e.g. Sulfurifustis and Thiobacillus), of which are more
abundant at greater depths, whereas the tailings of site A have a higher proportion of potential As-cycling and -resistant genera (e.g. Methylocystis and Sphingomonas). The microbial
communities appear to be highly correlated to depth, S#, Fe#, pH, and the average valence of As.
The variation in the average valence of As correlates well with the abundances of N, S, Fe, and
methane-cycling bacteria (e.g. Nitrospira sp., the order Thermodesulfovibrionia, and
Methylocystis sp.). Aerobic and anaerobic bioleaching experiments were conducted on three
samples (in duplicate) from each site, with six samples characterized by high and/or low Co, Fe
and S#’s and three bulk, site-specific samples. The experiments used the tailings native consortia
and had three methods/treatments. The first two were for chemolithotrophic and heterotrophic
bacteria enrichment, with the third serving as a control or baseline experiment. The experiments
ran for 18-weeks, with (1) biweekly measurements of pH, Eh, and total and dissolved metals,
and (2) analysis of the microbial community composition through 16S rRNA DNA extraction at
experiment completion. The highest abundance of As-reducing and -oxidizing genera (i.e.
Delftia and Dechloromonas) were observed in the heterotroph-enrichments, which was
additionally characterized as having the highest Co and As recovery (0.94 and 29.8 %,
respectively). Samples that were composed of a higher proportion of Co, Ni, Zn-arsenates and
Fe, Co-arsenides were observed to be enriched in Fe-reducing bacteria or As-reducing and -
oxidizing genera, respectively. The enrichments were able to successfully shift the microbial
communities to those involved in As-cycling. However, further work is required to determine
what hindered the metal recovery process, i.e. future micro- and/or nano-scale studies may
indicate that Co and As precipitated as Co-phosphates
CROSH COVID Conversations: Screening and Tracking for Workplaces
No full textIn Part 1 of CROSH COVID Conversations, panelist Dr. Katie Goggins generally discuss COVID-19 workplace entrance screening and, more specifically, the temperature measurement aspect of the screening process. Patrick James Trottier discusses the technology behind COVID-19 tracking and how it applies to the workplace. Dr. Goggins and Mr. Trottier also answer audience questions on the subject.In this webinar, panelist Dr. Katie Goggins generally discuss COVID-19 workplace entrance screening and, more specifically, the temperature measurement aspect of the screening process. Patrick James Trottier discusses the technology behind COVID-19 tracking and how it applies to the workplace. Dr. Goggins and Mr. Trottier also answer audience questions on the subject
CROSH COVID Conversations: Crisis and Opportunity in the Workplace
No full textIn Part 4 of CROSH COVID Conversations, Dr. Diana Coholic talks about individual capacities and strategies that can strengthen our abilities to cope and adjust to today’s challenging realities during COVID-19. Next, Dr. Ann Pegoraro discusses Crisis as Opportunity: What we have learned from past crises and how we can use that knowledge during the current pandemic. We then have a discussion with both panelists featuring audience questions
The Box: creating cross-disciplinary collaboration through architecture
No full textThis thesis was born through and exploration of the Architectural realms modus operandi in terms of the exclusionary
nature that seems to permeate throughout the industry. The question of who can make and experience Architecture brings
to centre stage an imbalance. Political, economic and social barriers all stand in the way of Architecture being a more
democratic form. It is an ironic duality that lies here as Architecture is simultaneously one of the most public and private
forms of art one can make. Public in its symbolic and monumental nature, while private in its inherent need to protect and
shelter. It is an unfortunate truth, but very few people are fortunate enough to experience Architecture.
However, even within its exclusive nature, Architecture, at times finds itself doing the opposite. Moments of sharing and
collaboration within schools, institutions and the fields showcase an ability for Architecture to be by and for more people.
The Open City created by the Valparaiso school of Architecture,1
and the enigmatic and visual magazines by Archigram
brushed on a more inclusive Architecture.2
That being said, even within these instances, it is still limiting, as only those
who may be fortunate enough to attend the schools or be directly connected to the social circles of the individuals involved
may benefit from it.
What is needed then is an Architecture that openly calls for collaboration from a wider range of fields without a bias of
class, schools or connection. Be it artists, scientist or engineers; through the joint efforts of a group containing a wider
skillset, the sharing and learning through collaboration will help Architecture broaden its sense of collaboration.
The vehicle that is then proposed as the Architectural answer to this is The Box, a cross disciplinary creative residency
that will operate in a nomadic nature. The Box will create an open invitation for creatives of all fields to come together
on the completion of an art installation, allowing for a wide range of projects to possibly appear. However, as a means of
mitigating the exclusion that may come with a project like The Box, it will use the world’s existing networks of highways,
railroads, and shipping routes to affect as many people as it can. Paired with its quarter-annual schedule, the project will
aim to effect as wide an audience as possible.
The question then that my thesis asks is, can we use Architecture to create an Architecture that facilitates cross disciplinary
collaboration and learning to a wider audience than already exists
Diet: it’s all about location, location, location! How urbanization influences endocrine stress, isotopic signatures, and fecal antioxidants in eastern chipmunks (Tamias striatus)
No full textAs cities continue to expand on a global scale, animals gain greater access to human food
waste, and the consequences associated with the consumption this food waste are poorly
understood. Using eastern chipmunks (Tamias striatus) as a study species, I examined the
differences in cortisol concentrations and body condition scores, as well isotopic signatures of
carbon (∂13C) and nitrogen (∂15N), and fecal antioxidants from eastern chipmunks on an
urbanization gradient. I tested the hypotheses that: 1) chipmunks would have lower cortisol
levels and better body condition scores if they are living in more urban areas because urban
environments may contain higher amounts of human food waste relative to natural habitats, and
2) chipmunks would have higher carbon and nitrogen signatures and excrete more antioxidants
in more urban environments compared to their natural counterparts because they may be
consuming human food waste. Chipmunks were sampled across Sudbury, Ontario from 20 areas
with varying levels of urbanization. Each time a chipmunk was captured, hair samples, fecal
samples, and body measurements were collected. To quantify urbanization, I surveyed all study
sites over a three-day period to score the level of human activity. I found that cortisol
significantly differed among chipmunks across the gradient, such that chipmunks in more urban
habitats experienced the highest levels of cortisol. I found chipmunks and poorer body condition
in the most urban areas. Chipmunks in more urban habitats produced a higher nitrogen signature
than their natural counterparts, while no significant difference was observed in carbon or fecal
antioxidants. My results help us to understand differences in diet across as well as the
physiological changes associated with urban habitats, which may help us understand how other
species may respond to urbanizatio