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Giishpin Nonagzwaat Binoojiinyik Kanim Na Majiishkaami: determinants of obesity among indigenous children in six First Nations Communities in Northeastern Ontario
No full textBackground: Worldwide, childhood obesity rates are high and even higher among Indigenous children. Childhood obesity is of concern as it can result in metabolic conditions. Much has been written about the causes of obesity, usually focusing on individual behaviours, but a gap exists in understanding the social determinants of obesity in Indigenous populations. Methods: Survey data was collected from First Nations students in grades 6 to 8 through a diet and health behavior survey. Measurements including height, weight and waist circumference were taken. Focus groups with 33 caregivers were conducted to explore the determinants of physical activity and nutrition. Results: The prevalence of overweight/obesity in children was 65.8%. The prevalence central obesity was 37.7%. There was a strong positive correlation between waist circumference (cm) and BMI z scores (rs = 0.84, p>0). Daily physical activity (DPA) of 60 minutes per day was associated with a BMI ≤85th percentile and a waist circumference ≤90th percentile. Girls consumed 3.5 servings of fruits and vegetables and boys consumed 2.5 servings. Consuming fruit juice was directly associated with central obesity. Normal weight was associated with participation in at least four types of cultural activities. Caregivers identified impediments to physical activity as financial, recreational technology, safety concerns, and community activation. Changes in lifestyles, influenced by the consequences of colonization, have resulted in reduced physical activity. Colonial policies result in funding challenges for children’s recreation programs and a reliance on government develops. Safety concerns stem from intergenerational trauma created by colonial policies. Dietary decisions were influenced by the availability of fish and game, hunting and fishing regulations, food insecurity and the proliferation of processed foods. Dietary decisions are influenced by the contamination of traditional territories, the marginalization of culture, participation in the economy and issues of poverty. Conclusions: Waist circumference is an effective indicator of obesity along with BMI and should be used in public health screening of Indigenous children. Low fruit and vegetable consumption is of concern as is the consumption of fruit juice. Protective factors against obesity are 60 minutes of DPA and participation in at least four types of cultural activities. Colonialism is a determinant of physical activity, nutrition, and obesity in this population
Commissioning and verification of compressed air yield on the hydraulic air compressor demonstrator
No full textThe completion of the hydraulic air compressor (HAC) demonstrator at Dynamic Earth in
Sudbury, Ontario marks the beginning of a series of research activities to increase the efficiency
of compressed air production and build confidence in future commercial applications. Before any
proper experiments could be conducted on the HAC Demonstrator a series of commissioning
activities and testing was completed to i) calibrate the instruments, ii) check and understand losses,
and iii) verify, or otherwise, some of the assumptions made during the system design.
The practical work associated with this master’s thesis included the development of a human
machine interface (HMI) to allow for automated control of the HAC. Instrumentation and control
equipment was installed and routed to a control panel providing conditioned power and routes for
signals. Within the control panel, these are digitised and transmitted using TCP/ IP/ MODBUS
protocol, operating over a TopServer (Software toolbox, 2009) OPC backbone. The OPC Client
toolbox in MATLAB was adopted to interface with the OPC Server, and MATLAB’s App
Designer adopted for authoring the HMI. All I/O functionality is thus routed to MATLAB in which
a PID control loop was established between the HAC separator water level and the HAC’s
compressed air motorized globe valve. Thus, a reliable, flexible, scientific control interface and
data storage infrastructure was established for this novel compression plant as part of the master’s
work. The HAC Demonstrator can now effectively run a variety of experiments while recording a
wide range of data for analysis. To date, a series of 90 benchmark tests for compressor performance
have been completed in a systematic manner on the demonstrator to create a database of real HAC
operating conditions. This thesis thus represents the first formal publication of the HAC
Demonstrator’s complete performance under the baseline operating conditions.
Previous predictions of the compressed air yield and efficiency of a HAC of this size have been
made by Millar (2014), upgraded to weakly couple solubility loss by Pavese et al. (2016) and
refined using Young’s (2017) detailed coupling of solubility and psychrometric phenomena. The
predictions made by these models have been tested. The 1D hydrodynamic solubility models also
predicted a small beneficial ‘airlift’ effect on compressor performance, due to exsolution of
formerly dissolved compressed gas, that has also been reported upon.
One unexpectedly important factor that has been found to affect HAC performance that was not
anticipated in any of the models included the absolute surface roughness of rubber lined pipe, in
comparison to that of bare steel pipe. High precision experiments are reported upon that have
produced reliable values for absolute surface roughness for rubber lining materials, that have now
been adopted in the HAC models, and may be adopted more widely too. The occurrence of
detrainment, water jet-free fall and air re-entrainment is speculated upon as the source of
previously unreported loss in the air-water mixing process, based on pressure profiling
observations undertaken over the complete performance envelope of the Dynamic Earth HAC
Demonstrator
Using group role assignment to solve Dynamic Vehicle Routing Problem
No full textThe Dynamic Vehicle Routing Problem (DVRP) is a more complex problem than the traditional
Vehicle Routing Problem (VRP) in the combinatorial optimization of operations research. With
more degrees of freedom, DVRP introduces new challenges while judging the merit of a given
route plan.
This thesis utilized the time slice strategy to solve dynamic and deterministic routing
problems. Based on Group Role Assignment (GRA) and two different routing methods (Modified
Insertion heuristic routing and Modified Composite Pairing Or-opt routing), a new ridesharing
system has been designed to provide services in the real world.
Simulation results are presented in this thesis. A qualitative comparison has been made to
outline the advantages and performance of our solution framework. From the numerical results,
the proposed method has a great potential to put into operation in the real world and provides a
new transit option for the public
Cancer cell behaviour in response to chemotherapeutics - a study of docetaxel induced inflammatory cytokine production and the effect of lipopolysaccharides
No full textThe study of cancer is an ever‐evolving discipline and since the 1950's it has been driven
by fundamental scientific research using cultured human tumour cell lines isolated from human
cancer patients. Over the years it has become evident that patients with cancer of the breast,
ovaries, and several other tissues, often respond well to initial chemotherapy treatment, only
to be left with tumours that have become resistant to the cytotoxic effects of chemotherapy.
This has prompted decades of cellular and mouse‐based studies to characterize the many
biomolecular processes by which tumour cells in their microenvironments survive and
reproduce in the presence of chemotherapy drugs. This dissertation discusses the role of
cytokine production in chemotherapy drug efficacy both in the laboratory and the clinic.
Cytokines are naturally released by healthy epithelial, endothelial, and immune cells to convey
important messages to other cells and tissues of the body, driving immune responses upon
recognition of pathogens or cellular damage. Cytokines have become increasingly considered
for their roles in stalling or accelerating cancer progression as well as improving or limiting drug efficacy. In this thesis, we present primary research results that provide novel insight into the
mechanism by which chemotherapy drugs induce inflammatory cytokine production and
release from human tumour cells. We show that the semi‐synthetic taxane derivative
docetaxel, as well as other structurally distinct chemotherapy drugs, induce the release of the
inflammatory cytokine TNF‐α from breast and ovarian tumour cell lines. Constitutively
increased production and release of TNF‐α and CXCL1 from breast and ovarian tumour cells was
also observed upon their selection for survival in increasing concentrations of docetaxel. Docetaxel‐resistant cells were less responsive to acute treatment with docetaxel than their
drug‐naive parental cell lines. These cells exhibited increased expression of the plasma
membrane‐bound drug‐export protein, P‐glycoprotein, which promotes the efflux of docetaxel
and other drugs from tumour cells. Interestingly, restoration of drug into the docetaxel‐
resistant cells not only restored the drugs' cytotoxic effect but also the ability of the cells to
respond to drug with increased TNF‐α release. Current paradigms suggest that this response
occurs through activation of the pathogen recognition receptor Toll‐like receptor 4 (TLR4),
involving direct interaction with docetaxel at the cell surface. This model appears inconsistent
with our results showing that cellular drug accumulation is necessary for the response of
increased TNF‐α release to occur. We also show that the TLR4 agonist, lipopolysaccharides
(LPS), causes increased production of TNF‐ in the presence of docetaxel and increased
docetaxel cytotoxicity for both wildtype and docetaxel‐resistant MCF‐7 tumour cells,
representing a potential novel strategy to restore chemoresponsiveness in chemoresistant
tumours
Genetic background and environmental effects on single nucleotide polymorphisms in the NADPH pathway
No full textA major focus in modern genomics is determining the connection between genotypes and
quantifying phenotypes. In this connection, many factors come into play including different
genetic backgrounds, genetic variation at a locus, and environmental conditions. Genetic
variation in Drosophila melanogaster, and specifically the simple polymorphisms within Malic
enzyme (Men), can provide insight into the pathways between genotypes and phenotypes.
Globally, there are two polymorphic sites in the malic enzyme gene. On site is near the protein
(MEN) active site and found at an allelic frequency of 50% glycine amino acid and 50% alanine
amino acid. The second polymorphism is buried within the protein and found at an allelic
frequency of 90% methionine amino acid and 10% leucine amino acid. To determine the
complexity of the pathway between genotypes and phenotypes, multiple genetic backgrounds for
each genotype, using multiple D. melanogaster lines, were included to explore and quantify
genetic background effects, and paraquat was used to induce oxidative stress. The biochemical
characteristics of the alleles varied significantly between the genotypes under benign conditions
and both polymorphic sites effected some phenotypes. The first site played a role in the MEN
Vmax and Km; the glycine allele had 14% higher Vmax activity than the alanine allele and the
glycine allele had 8% higher Km than the alanine allele. The second site influenced the Km and
Vmax/Km ratio (relative activity); the methionine allele had 34% higher malate Km than the leucine
allele the leucine allele had 52% higher relative activity than the methionine allele. Interestingly,
the protein product encoded by the rarer allele, leucine, had a higher relative activity and lower
Km concentration, having a large impact on the enzymatic phenotype. These extreme phenotypes
of that allele may be an indication of the why the allele is maintained at 10% across populations.
Different lines with the same genotype had different biochemical phenotypes, indicating the
importance of backgrounds effects influencing the final phenotype. Further, the flies’ phenotypes
differed between benign and oxidative stress conditions. Flies exposed to paraquat had a
decrease in MEN Vmax, and the MEN alleles did not significantly differ from each other. Overall,
the findings from this study suggest that the final phenotype are strongly influenced by the
polymorphisms found in MEN, the interactions between genetic background and environmental
conditions
Validation and verification of an analytical method to identify and quantify selected amphetamine-related drugs in whole blood
No full textThe abuse of amphetamine-related drugs (ARDs) is an epidemiological phenomenon in Saudi
Arabia. This drug abuse is found to play an important role in early mortality due to traffic
accidents, violence, and overdose. Therefore, control ARDs abuse is crucial. In forensic
toxicology, ARDs analysis is carried out to identify human actions, such as driving under the
influence of drugs, clarify the manner and cause of death, and elucidate drug use. This study has
yielded practical analytical assay to using whole blood (WB) as a biological matrix in ARDs
analysis by using ultra performance liquid chromatography in coupling with quadrupole time of
flight mass spectrometry (UPLC-qTOF-MS). Here, two different types of solid phase extraction
(SPE) were evaluated. Molecularly imprinted polymers (MIP-SPE) was found to deliver a highly
clean extract, however, ephedrine (EPH) interference was proved to leach from the polymer
matrix of the sorbent materials. Mixed mode cation exchange (MMSPE) was found ideal to
extract ARDs from WB matrices. The analytical method was developed and validated according
to the Scientific Working Group for Forensic Toxicology (SWGTOX) Standard Practices. The
validated method was found capable of quantitative analysis of methylphenethylamine (BMP)
and detection of one of its metabolites in WBs of rats exposed to BMP by peritoneal injection
Towards the development of a culturally sensitive, empowerment-based sexual assault resistance model for Anishinaabe women
No full textIn Canada, sexual violence against Indigenous women is an unsettling, national human
rights crisis. Conservative estimates are that 57% of Indigenous women have been sexually
assaulted (Native Women’s Association of Canada, 2011). Compared with non-Indigenous
women they experience three times more intimate partner violence, suffer from more extreme
violence and are targeted by both Indigenous and non-Indigenous men (Boyce, 2016).
The House of Commons, Special Committee on Violence Against Women in 2014
emphasized the need for the development of education and prevention programs to address
violence against Indigenous women (Ambler, 2014). Sexual violence against Indigenous women
intersects with historic genocide, intergeneration trauma, entrenched racism, sexism, and
poverty. Although some sexual assault resistance programs have been found to lessen sexual
assaults by 50% (Orchowski & Gidycz, 2018), none have been developed that address the unique
history, culture, and needs of Indigenous women.
This thesis explores the development of a culturally sensitive, empowerment-based
sexual assault resistance model and preliminary program for Anishinaabe women. The
development was informed by peer-reviewed literature and in collaboration with two
Anishinaabe elders. The emergent model and preliminary program were reviewed by a focus
group of three professional Anishinabek helpers. This study is a step towards lessening sexual
violence against Indigenous women in Canada, supports social work competence and practice for
working with Indigenous women, and furthers sexual violence prevention efforts in Ontario’s
north.Masters of Social Work (MSW
Étude de la situation socioculturelle et linguistique des jeunes franco-ontariennes et franco-ontariens face aux défis d'accès aux services de santé de qualité en français à Timmins
No full textConduite selon la méthode qualitative et envisagée épistémologiquement selon
l’approche constructiviste combinée à la démarche herméneutique et au modèle
écologique, cette recherche de maîtrise en travail social est une problématique qui, tout
en étant aussi la même que celle des Francophones de Timmins que nous rencontrons et
avec lesquels nous partageons la vie au quotidien, s’est inspirée de notre expérience
migratoire et professionnelle vécue en matière d’un cruel manque de services de santé de
qualité en français à Timmins. Afin de frayer les avenues susceptibles de dénouer la
complexité et l’ampleur des enjeux liés à cette problématique, cette recherche visait à
explorer les représentations, les perceptions, les expériences et les alternatives que les
jeunes Franco-Ontariennes et Franco-Ontariens de Timmins âgé(e)s de 20 à 30 ans, ceux
et celles de naissance ou les JFON et d’adoption ou les JFOA, ont de leur situation
socioculturelle et linguistique par rapport aux défis d’accès aux services de santé de
qualité en français à Timmins. Ainsi, grâce à la réalisation des dix entrevues qualitatives avec ces jeunes, la présente
étude permet de comprendre que la situation socioculturelle et linguistique de
l’échantillon typiquement de ces dix JFON et JFOA témoigne essentiellement de la
conscience de l’existence de nombreux défis d’accès aux services de santé de qualité en
français à Timmins, et que la cause de ces défis se situe, en dernière analyse, dans la
prédominance de l’anglais, aussi bien dans la ville de Timmins que dans la prestation de
ces services, notamment à l’Hôpital de Timmins et du district. Ce faisant, cette étude fait
toutefois voir que ce sont les JFOA qui, à la différence des JFON, dont la majorité parle
plus naturellement les deux langues officielles du Canada (le français et l’anglais), ont
nécessairement besoin de la langue française, considérée comme leur première langue
officielle parlée pour accéder aux besoins vitaux dans la communauté franco-ontarienne,
dont l’accès aux services de santé de qualité, puisqu’ils/elles sont majoritairement plus
limité(e)s en anglais, ainsi que les personnes âgées francophones ontariennes.
Développant une réflexion sur ses résultats selon le cadre d’analyse écologique, cette
recherche montre que les problèmes de fonds en matière de santé des FrancoOntariennes
et Franco-Ontariens notamment de Timmins se trouvent dans l’exo et le
macro systèmes, dans lesquels les valeurs de la société ontarienne et les lois politicojuridiques
se situent. Par conséquent, cette recherche situe la vraie solution aux défis
d’accès, notamment aux services de santé en français en Ontario, dans la mise en
exergue de la Charte canadienne des Droits et Libertés pour officialiser le bilinguisme,
notamment en Ontario. Ainsi, ce mémoire s’avère un outil à offrir aux personnalités
politiques franco-ontariennes déplorant le sort particulièrement des Franco-Ontariennes
et des Franco-Ontariens et de leurs défis.Maîtrise en Service Socia
An assessment of the validity and acceptability of a novel, audio-video food journaling method, in a free-living setting
No full textIntroduction
A novel method of dietary assessment was introduced in a field study with wildland firefighters,
published in 2017. The purpose of this thesis was to validate this novel, audio-video method of
dietary assessment, and to determine whether it can be integrated into clinical practice, to replace
written food journals. The validation process was completed in two phases and is presented as
two manuscripts within this thesis.
Manuscript One
Phase one was designed to validate the audio-video method in comparison to the gold standard:
weighed food assessment; in a free-living setting. With the exception of Vitamin E (mg) and
total weight (g), kilocalories, macro and micronutrient values were highly correlated between the
audio-video diary recorded estimations and weighed food items. We concluded that the novel
method was able to make accurate estimations of energy and nutrient intake, and may therefore
be a meaningful alternative to diary recording in a free-living setting.
Manuscript Two
Phase Two was designed to assess the application of the 3-day, audio-video method in a clinical
setting, to replace the current method of 3-day, written food journaling. We found that the diet
assessments, as performed by a Registered Dietitian for the same participants, were comparable
between written and audio-video diaries. In consultation with the Registered Dietitian, we
conclude that the audio-video method is acceptable for use in clinical practice.
iv
Conclusion
The audio-video method is a suitable method for assessing food items, when the portion sizes
from the video are estimated by persons with training on portion sizing (i.e. researchers or
Registered Dietitians). In addition, the AV method was determined to be an acceptable method
for use in clinical practice, to replace written food journals. Participants indicated that if the
method was developed into a mobile phone application, for use on their personal device, they
would be more likely to accept it as a food journaling method, when compared to the written
method of food journaling