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Evaluating mineralogical, geochemical and microbial relationships within sulfur-bearing mine wastes; a multianalytical and multivariate statistical approach
No full textMine tailings harbour a dense population of extremophiles that play key roles in metal and mineral
transformations. While microbially mediated mineral oxidation and reduction within sulfurbearing
mine waste has been widely reported, linkages and statistical significance between
environmental parameters and geochemical and mineralogical compositions with microbial
community diversity has not yet been documented. A combined geochemistry, mineralogy, and
genomics approach has been used in this study to better understand the biogeochemical processes
occurring within a gradient of tailings dam materials both at surface and down a depth profile.
Complex microbial diversity patterns across sample types, environmental conditions, spatial
locations, and geochemical and mineralogical compositions, are addressed using multivariate
statistical analysis. Additionally, scanning electron microscopy (SEM) and transmission electron
micrscopy (TEM) are used to analyze the compositional and morphological features of microbemineral
assemblages. A total of 40 sulfur-bearing tailings samples have been collected aseptically
from five constructed tailing dam structures, in Sudbury, Ontario. Samples have been grouped into
three zones including oxidized, transition, and unoxidized, which are distinguished by pH, munsell
colour and mineralogical composition. Oxidized material is composed of silicates and ironhydroxides
(goethite) and iron-hydroxy sulfate minerals (jarosite, schwertmannite), with contact
pH ranging from 2.6 - 4.5. Material from the unoxidized zone consists mainly of silicates and
sulfides (pyrite, pyrrhotite, chalcopyrite and greigite), with a higher contact pH ranging from 4.14
- 5.71. Transitional material is dominantly composed of silicates, but contains both sulfides and
secondary iron and sulfate minerals, with pH ranging from 3.6 - 5.31. Microbial community
composition and structures are often attributed to their surrounding geochemical environments.
However, no significant correlations are observed between total metal content and microbial
community compositions across the analyzed samples. However, community compositions and
structures exhibit significant changes based on the contact pH ranges and mineralogical
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compositions of the analyzed tailings material. Oxidized, transition, and unoxidized material
exhibit similar taxa, however, relative abundance of taxa exhibits extensive variability across the
identified zones. Key indicator species are statistically tested across the three alteration zones, with
microorganisms whose metabolic functions underpin iron and/or S oxidation and/or reduction
identified as microorganisms characterizing alteration zones. Microbial-mineral assemblages
analyzed at the nano-scale exhibit minerals that were not identified by routine whole sample
analysis (XRD), thereby indicating the importance of performing both SEM and TEM to fully
understand microbial-mineral interactions. The microbial-mineral relationships observed in this
study both at the micro- and nano-meter scale have resulted in furthering understanding of
biogeochemical processes occurring within the analyzed sulfur-bearing tailings material
Smile judgment in substance use disorders and its relationship to interpersonal and emotional functioning: an eye-tracking investigation
No full textThe current study explored the judgments individuals with Substance Use Disorders
(SUDs) make regarding the authenticity of enjoyment smile expressions and masking
smile expressions containing traces of negative emotions. Accuracy at identifying the
masked negative emotions were also examined. Eye-movements were recorded to
observe relationships between attentional processes and smile judgment. Additionally, the
relationship between smile judgment, emotion dysregulation, and interpersonal problems
were also investigated. Twenty individuals with SUDs being treated from a local
treatment center and twenty individuals matched on gender/age participated in the smile
judgment task, which involved a smile expression characteristic of enjoyment and six
smile expressions containing traces of either fear, disgust, anger in eyes, anger in mouth,
sadness in eyes, and sadness in mouth. Results indicated that individuals with SUDs were
no different in their categorization of the smiles. The lack of difference may be due to
their previously observed biases at interpreting expressions as negative, as the results
indicated that individuals with SUDs were significantly more likely to report the presence
of negative emotions in the expressions. They were also more often incorrect in their
identification of the masked emotions. No link was observed between smile judgment and
attentional processes. Emotional and interpersonal functioning were related more to the
ability to distinguish smile authenticity than the ability to identify masked emotions
Urban First Nations men create a ribbon shirt
No full textThis thesis examines the experiences of three men, two First Nations and one Metis who
participated in the creation of a Ribbon Shirt at the Shkagamik-Kwe Health Centre (SKHC) in
Sudbury, Ontario. This research demonstrated how specific programming can nurture a
connection to traditional ways in urban First Nations and Metis men and promote an embracing
of First Nations identities. This study utilized both Phenomenology and elements of Photovoice
research methodologies to gather participant narratives, this highlighted the lack of services
specifically for men and the benefits of focused programing that included cultural teachings.Master of Social Work (MSW
Understanding the characteristics that contributed to Québec athletes’ olympic successes moving into, during, and out of the Olympic Games
No full textThe current study examined the characteristics that influenced four of the most successful
Québec athletes’ performances moving in, during, and out of the Olympic Games. Their
experiences were explored using media data (i.e., newspapers articles from the province of
Québec) through an inductive thematic analysis. Seven main practical conclusions were created
from this study with the first five relating to the three meta-transitions explored, and the last two
relating to limitations created by the the methodology used in the study. The conclusions are: 1)
Developing an empowering coach-athlete relationship in order to facilitate the athletes’
performances, 2) Starting a competition easy to finish strong, 3) Creating realistic but
challenging goals for every step of the Olympic season, 4) Consciously learning form success
and failures/mistakes, 5) Using mainly intrinsic motivation when competing, 6) The
unmentioned importance of sport psychology services, and 7) The omission of information about
provincial versus national pride
L’influence de l’épistémologie sur la pratique enseignante du volleyball au Bénin
No full textL’objectif de l’étude est de mettre en évidence l’influence de l’épistémologie sur la pratique de
l’enseignant en situation de classe de volleyball. Autrement dit, elle vise à rendre compte de l’effet qu’induisent
le rapport au savoir, son expérience personnelle, son expérience professionnelle et sa conception sur les
transactions didactiques qu’il opère. Pour l’atteinte de notre objectif, deux modèles théoriques ont servi de
socle à cette étude : la théorie de l’action didactique conjointe de Sensevy (2007) qui permet de comprendre
l'action didactique conjointe des enseignants d'EPS/entraîneurs et de leurs élèves lors de l'enseignement du
volleyball ; le déjà-là du sujet de Terrisse (2001) quant à lui permet de vérifier la singularité de l’enseignant
face à l'APS enseigné à travers son expérience professionnelle et pratique. L’analyse didactique des actions
menées par les enseignants/entraîneurs, et celle des transpositions didactiques qu’ils ont opérées varient d’un
enseignant à un autre et sont fonctions du niveau de maitrise des élèves. Ceci nous amène à dire que
l’épistémologie pratique à un poids sur les transactions didactiques qu’ils opèrent en situation de classe. De
même les enseignants font recours de façon générique à l’approche dialectique. Toutefois le recours aux deux
approches par certains enseignants vise à plus insister sur la réussite du geste technique
Metabolic engineering aimed at the production of keto acids from glycerol : an industrial by-product
Get PDFWorldwide, energy consumption is at an all-time high and projected to increasingly grow
in the upcoming years. Thus, it is critical to uncover alternative sources of energy that are
independent of fossil fuels and environmentally neutral. The transformation of biomass into
various energy-rich chemicals is an important strategy that is being pursued globally. Biodiesel
can be an interesting substitute to fossil fuels. However, this process generates excessive
amounts of glycerol, a byproduct that needs to be converted into valuable products if the
biodiesel industry is to be sustainable. The principle objective of this thesis is to study how glycerol can be used as a raw
material by microbial systems to produce valuable products. The soil microbe, Pseudomonas
fluorescens widely utilized in the numerous biotechnological applications due to its nutritional
versatility is an obvious choice to tailor into a glycerol-transforming nanofactory. The abiotic
modulators namely hydrogen peroxide (H2O2) and manganese (Mn) afforded uniquely facile
means of triggering metabolic reprogramming aimed at the enhanced formation of pyruvate and
α-ketoglutarate (KG). Under the influence of H2O2, P. fluorescens engineers an intricate
metabolic network to synthesize ATP and pyruvate. As oxidative phosphorylation is severely
impeded, the microbe invokes substrate level phosphorylation to generate energy. This is
accomplished via the increased activities of various enzymes including pyruvate carboxylase
(PC) and phosphoenolpyruvate carboxylase (PEPC) that were analyzed by blue-native
polyacrylamide gel electrophoresis (BN-PAGE) and high performance liquid chromatography
(HPLC). The high-energy phosphoenolpyruvate (PEP) is then converted into ATP and pyruvate,
a process mediated by pyruvate phosphate dikinase (PPDK), phosphoenolpyruvate synthase (PEPS) and pyruvate kinase (PK). Supplementation with a micro-nutrient such as Mn, a divalent
metal involved in a variety of enzymes results in the reprogramming of the metabolic networks
aimed at the accumulation of KG. The increased activities of isocitrate dehydrogenase (ICDH)-
(NAD)P dependent and aminotransaminases aided the exocellular secretion of KG. The
overexpression of pyruvate carboxylase (PC) that is evident in the Mn-treated cells provides
oxaloacetate, an important precursor to the synthesis of citrate, a key ingredient in the synthesis
of KG. Isocitrate lyase (ICL), fumarate reductase (FUMR), succinate semialdehyde
dehydrogenase (SSADH), α-ketoglutarate decarboxylase (KDC) and γ-aminobutyric acid
transaminases (GABAT) work in concert to produce KG. 13C-NMR helped identify the
metabolites participating in the metabolic networks. Immunoblot experiments confirmed the
presence of overexpressed enzymes. These disparate metabolic pathways that promote the
overproduction of the keto-acids in P. fluorescens have the potential of converting glycerol to
value-added products commercially. As the process utilized is devoid of any genetic
manipulation, it can be readily implemented in an industrial setting. In conclusion, both H2O2
and Mn can orchestrate metabolic changes in P. fluorescens inducing the production of pyruvate
and KG from glycerol respectively. These chemical manipulations may also be applied to other
microbial systems
Nesting in close quarters: causes and benefits of high density nesting in painted turtles
Get PDFNesting is a costly time for female turtles, both energetically and from threat of predation.
Females must ensure maximum survival of offspring for population stability and individual
fitness. I observed signs of communal nesting in female Painted Turtles (Chrysemys picta).
My goals were to determine; are females choosing to nest at high nest-densities, what cues do
they use to select nest sites, are offspring benefitted. Using ArcGIS, I found that females
nested in clusters, the location of clusters varied among years, and that nest site selection was
not strongly determined by environmental characteristics. When female turtle models were
placed on the nesting embankment females nested most often with the highest density of
models. In ~25% of cases, nests were so clustered that eggs were deposited directly into
existing nests or directly beside existing nests. Survival of clustered nests (49%) was higher
than that of solitary nests (39%). In incubators, older clutches had faster incubation times,
suggesting embryonic communication as a mechanism promoting hatching synchrony. We
strongly suggest that female Painted Turtles choose to nest in close proximity to conspecifics,
and that this clustering results in a fitness benefit
Vibration toolkit: an occupational health education intervention for the mining industry
Get PDFBackground: Workers in the mining industry are exposed to whole-body vibration (WBV), hand-arm vibration (HAV), and foot-transmitted vibration (FTV). The purposes of the study were to: critically review occupational health and safety education intervention programs that have been conducted within rural and northern communities and industries; examine the vibration-focused education resources in northern Ontario; and develop, implement, and evaluate an occupational health education intervention program, the Vibration Toolkit
Nanoscale examinations on the sequestration of Cu by organic material in contaminated surface soils in Timmins, Ontario
Get PDFThe deposition and alteration of particulate matter (PM) in soils is a world-wide health concern.
This study investigates the fate of Copper in organic-rich surficial soil layers (0-5 cm)
contaminated by mining related activity at the Timmins Kidd Creek metallurgical site, Canada.
The sequestration and mobilization of Cu by organic material (OM) in the soil layer is investigated
using focused ion beam (FIB) technology and transmission electron microscopy (TEM). Copper
occurs as incidental metallic Cu and covellite (CuS) nanoparticles (NPs), formed via ion reduction
by humic substances and magnetite. Additionally, TEM analysis of the colloidal fraction, extracted
via ultracentrifugation from the surface soil layer, indicates the occurrence of incidental covellite
NPs in close association with dissolved OM. This study shows for the first time that Cu is
sequestered as incidental metallic Cu and covellite NPs within OM and magnetite in surficial
organic-rich soil layers. Furthermore, the mobility of Cu is facilitated through the transport of
covellite nanoparticles embedded within organic colloids