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Immersive wilderness experiences: an exploration of women's narratives
No full textThe purpose of this qualitative study was to invite fifteen women to explore memories of their immersive wilderness experiences. Based on this writer's own wilderness experience, the central question was whether participants would be drawn to partake in an immersive wilderness experience because of a recognition of its inherent benefits. Fifteen women were interviewed using a semi-structured interview format, guided by a set of eleven questions, their definition of wilderness, the role the wilderness played in their experience, any therapeutic or health related benefits, the impact of these benefits and whether there were any distinctive aspects of participating in a woman-only immersive wilderness experience. Interestingly, major themes emerged which related more so to the activity, than the synergy between human and the wild elements. Major themes included activities, women only wilderness experiences and the qualities of wilderness as a setting, which included elements of escape and an altered state of being.Master of Social Work (MSW
The effect of chemotherapy treatment on Ribosomal RNA integrity and ribosomal protein composition in ovarian cancer cells
No full textRecently we have demonstrated that several chemotherapy agents, of distinct mechanisms, promote highly reproducible ribosomal RNA (rRNA) degradation patterns, a phenomenon we call RNA disruption. These reproducible rRNA degradation bands have been observed in total RNA preparations from several cancer cell lines originating from various tissues. However, the effect of chemotherapeutic agents on ribosomal integrity and composition (including changes in rRNA and protein content) has not been examined. The purpose of the present study was to investigate the effect of docetaxel (DXL) chemotherapy treatment on ribosomal RNA and protein content in the A2780 ovarian carcinoma cell line. This involved isolation of ribosomes from untreated and DXL-treated A2780 cells using a differential centrifugation method. Differences in ribosomal RNA integrity and protein composition due to DXL treatment were determined using capillary gel electrophoresis (for rRNA), and 1D or 2D gel electrophoresis (for ribosomal proteins). Specific ribosomal proteins were detected by western blotting and quantified using densitometry. We report that DXL treatment of A2780 cells results in time-dependent degradation of rRNAs within isolated ribosomes, as well as changes in their relative protein composition. The DXL-induced changes in ribosome protein composition appeared to precede extensive rRNA degradation and were not observed in DXL-resistant A2780 cells
Biochemical and molecular characterization of microbial communities from a metal contaminated and reclaimed region.
No full textMetal contamination in the Greater Sudbury Region (GSR) resulted in severe environmental degradation. Soil liming and tree planting have been the main approaches to restoring the damaged ecosystem. The specific objective of the present study was to assess the effects of soil metal contamination and liming on 1) microbial biomass and abundance, 2) bacterial and fungal diversity, and 3) enzymatic activities and soil respiration. Phospholipid fatty acid (PLFA) analysis and 454 pyrosequencing were used to address these research objectives. Total biomasses for bacteria, arbuscular fungi (AM fungi), other fungi and eukaryotes were significantly lower in metal contaminated compared to uncontaminated reference areas. Analysis of bacterial communities revealed Chao1 index values of 232 and 273 for metal contaminated and reference soils, respectively. For fungi, the Chao index values were 23 for metal contaminated and 45 for reference sites. There was a significant increase of total microbial biomass in limed sites (342.15 ng/g) compared to unlimed areas (149.89 ng/g). Chao1 estimates followed the same trend. But the total number of OTUs (Operational Taxonomic Units) in limed (463 OTUs) and unlimed (473 OTUs) soil samples for bacteria were similar. For fungi, OTUs were 96 and 81 for limed and unlimed soil samples, respectively. Bacterial and fungal groups that were specific to either limed or unlimed sites were identified. Bradyrhizobiaceae family with 12 genera including the nitrogen fixing Bradirhizobium genus was more abundant in limed sites compared to unlimed areas. For fungi, Ascomycota was the most predominant phylum in unlimed soils (46.00%) while Basidiomycota phylum represented 85.74% of all fungi in the limed areas. Detailed analysis of the data showed that although soil liming increases significantly the amount of microbial biomass, the level of species diversity remained statistically unchanged. Soil respiration rates were higher in limed soils (65 ppm) compared to unlimed soils (35 ppm). They were significantly lower in metal contaminated sites (55 ppm) compared to reference sites (90 ppm). β-glucosidase (BG), cellobiohydrolase (CBH), β-N-acetylglucosaminidase (NAGase), aryl sulfatase (AS), acid phosphatase (AP), alkaline phosphatase (AlP), glycine aminopeptidase (GAP), and leucine aminopeptidase (LAP) activites were significantly higher in limed compared to unlimed sites. Metal contamination significantly reduced the activities of these enzymes with the exception of LAP. An opposite trend was observed for peroxidase (PER) enzyme activity that was higher in unlimed and metal contaminated sites compared to limed and reference areas
Monte Carlo simulations and experiments of Bessel beams and tissue-like phantoms interaction
No full textIn this thesis, the propagation of Bessel beam in tissue and its potential advantages were
explored numerically and experimentally. In the numerical simulations, the Monte Carlo
method is used to simulate the propagation of Gaussian and Bessel beams in tissue. By
convolving the impulse profile generated by a pencil beam’s propagation with either
beam intensity profile, the response of the propagation of the said beam can be
approximated. This process was done by modifying and using MCML and CONV
software which are available from the literature. Experimentally, the Bessel beams were
generated by a laser and axicons, and made to propagate through optical phantoms
formed with variable density intralipid solutions. The intensity distribution of the
transmitted Bessel beam at the exit of the scattering media was measured and compared
with transmittance results from simulation. At last, a separate experiment was designed to
investigate the reconstruction of a Bessel beam after it passes the optical phantom
The sleep behaviour and fatigue trends of wildland firefighters during non-fire and fire deployments
No full textOntario wildland firefighting is a hazardous and safety-critical operation with relatively high injury rates. This is indicated by the 10-year average of 4.46 lost-time injuries per 100 workers in Ontario wildland firefighting compared to 0.95-1.88 lost-time injuries in other occupations, as reported by the Workplace Safety and Insurance Board (WSIB). There is anecdotal evidence that fatigue is a major contributor to injury; however, evidence to support this is limited. Understanding fatigue trends, potential causes, and areas for intervention within the wildland firefighting profession were the main goals of the study.
Accordingly, contributors to fatigue were assessed during non-fire and fire deployments by collecting objective sleep (Actigraphy) and vigilance (Psychomotor Vigilance Test) measures, as well as subjective measures of fatigue and recovery (questionnaires). Data were collected from wildland firefighters during the high-risk months of the fire season within the province of Ontario.
Sleep duration less than six hours, sleep efficiency below 85%, and wake after sleep onset greater than 30 min were more frequently observed during high intensity, Initial Attack deployments. Sleep duration less than six hours were routinely observed in non-fire work periods, placing workers at risk of pre-deployment sleep-debt. Self-reported morning fatigue scores were low-to-moderate and were best predicted by Initial Attack deployment work conducted the day prior. Reaction times were slightly worse in morning periods during Initial Attack deployments, but scores were generally within acceptable ranges. Self-reported recovery scores were generally good regardless of work performed.
The current study highlights suboptimal sleep behaviours during both non-fire and fire suppression work, with sleep measures below recommended standards. High-intensity fire suppression periods (i.e. Initial Attacks) were predictably associated with the worst sleep and fatigue levels; but it is worth noting that the data were collected during a record low-hazard, firefighting season and may not reflect the sleep behaviours and fatigue levels encountered during a high-hazard fire season. Interventions for sleep/fatigue hygiene and awareness should be explored and are further discussed in this paper. The research methodology employed in the current study could be used in future investigations to determine the sleep behaviours and fatigue levels of wildland firefighters during a high hazard fire season
Cortisol and conservation: understanding barriers to the recovery of a critically endangered species using stress physiology
No full textChronic exposure to high levels of glucocorticoid hormones can be detrimental to survival and
reproduction. Captive breeding and release may inadvertently subject animals to conditions that
elicit an increase in glucocorticoids, if conditions in captivity or habitats in the wild are inadequate.
The critically endangered Vancouver Island marmot (Marmota vancouverensis) was used to investigate
variability in hair cortisol concentration, a measure of systemic glucocorticoid exposure. Marmots
were sampled from the captive, captive-release and wild populations. Captive animals had
significantly lower cortisol levels than wild animals. Several marmots were also sampled from the
historic wild population that lived on Vancouver Island prior to the proliferation of anthropogenic
disturbances. A comparison between contemporary and historic animals showed that marmots at
most colonies had cortisol levels that were the same as historic level. Three colonies had significantly
elevated cortisol levels. Cortisol concentration in the wild was best explained by proximity of a
colony to logging roads
Comparaison entre les étudiants de première génération et de seconde génération : engagement, rendement et persévérance
No full textCette thèse s’inscrit dans l’interdisciplinarité ; elle recourt aux données de l’Enquête
nationale sur la participation étudiante (NSSE) de 2014 et y exploite des variables scolaires
pour chaque répondant afin de vérifier s’il y a des différences entre les étudiants de
première et de seconde génération dans une université bilingue et triculturelle du nord de
l’Ontario. Une recension des écrits sur le thème fait remarquer des contradictions,
soulève des questions et note l’absence d’études sur le sujet en Ontario français. Les analyses quantitatives comparent 514 étudiants en première année d’études sur les
facteurs d’engagement, de rendement et de persévérance dans les études ainsi que sur la
langue d’usage. Nous avons trouvé peu de différences en ce qui a trait au profil des
répondants et noté un nombre limité de divergences entre les deux groupes concernant
l’engagement dans les études. Les analyses sur la langue d’usage ont fait voir
passablement plus de différences entre les groupes sur le facteur d’engagement dans les
études : les étudiants inscrits dans des programmes de langue française présentent un
meilleur rendement scolaire pour les crédits accumulés. Toutefois, le facteur
persévérance dans les études n’a fait voir aucune différence entre les catégories
d’étudiants, ce qui soulève des doutes sur ce résultat. Soixante-seize individus ont livré des remarques sur la qualité de leur expérience
universitaire que nous avons classées en neuf thématiques et analysées en lien avec les
questions de l’outil. Les commentaires signalent un nombre de convergences et quelques
inconsistances dans les données quantitatives. Bien que cette recherche signale plus de différences entre les deux groupes d’étudiants
que nous l’avions prévu, les divergences relevées sur le facteur d’engagement
corroborent celles des recherches repérées dans la littérature, sauf pour la dimension de la
langue d’usage qui suscite d’autres questionnements. Cette recherche souligne des
similitudes et des divergences entre les deux catégories d’étudiants et propose des
enquêtes ultérieures dans le but de trouver où conduisent les nouvelles avenues qui se
sont présentées
Ecology and food quality of fishes in coastal rivers of the far north of Ontario
No full textThe Far North of Ontario is home to over 24 000 people in 31 communities, and many of
these people rely heavily on wild fish as part of their diet. Six of these communities are
situated on the lower reaches of large river systems near the coast of Hudson and James
Bays. These large rivers, as well as numerous smaller rivers along the coast, are home to a
variety of fish species, including some presumed anadromous (migrating between fresh and
salt water) populations, that support important subsistence fisheries. However, little research
has been carried out on fish resources of these river systems, and basic information is
generally lacking. I examined fish populations from the lower reaches of 14 of these rivers in
terms of growth, trophic ecology, life history, and their suitability for human consumption
based on mercury and fatty acid content. Stable isotope and fatty acid compositions
indicative of predation on marine food sources were most evident in the presumed
anadromous species - Brook Trout, Lake Whitefish and Cisco. Compared to inland lakes of
the same drainage basins, coastal river populations of Northern Pike and Walleye grew faster
and occupied broader trophic niches, suggestive of an indirect marine influence on their diet.
In contrast, Lake Whitefish tended to grow more slowly in coastal rivers than in inland lakes.
Fish mercury concentrations in coastal rivers have not changed appreciably over the last ~ 30
years. Current fish mercury concentrations did not vary latitudinally among coastal rivers,
but were significantly higher than in inland lakes for Walleye, Lake Whitefish and White
Sucker. Fillet lipid and essential fatty acid (EPA+DHA) content decreased with increasing
latitude in Northern Pike, but not in other species. Both mercury and essential fatty acid
concentrations of fish muscle varied among rivers but there did not appear to be spatial
concordance between them. Presumed anadromous species - Brook Trout, Lake Whitefish,
Cisco – tended to have both the greatest concentrations of essential fatty acids and among the
lowest mercury concentrations, making them an especially high quality food source. Walleye
generally had the highest muscle mercury concentration and relatively low essential fatty
acid content
Indigenous culture as a strategy to defer Mushkegowuk youth from criminal behaviour in Moose Cree First Nation.
Get PDFThe over-representation of Indigenous Peoples within correctional facilities is a growing concern in Canada. This research study aims to determine if the community members of Moose Cree First Nation find it feasible to initiate traditional culture as a course to deter Indigenous youth from criminal behaviour. The study consisted of interviews with eight First Nation individuals by way of purposive and snowball sampling to recruit participants. Three major themes were discovered in the semi-structured interviews: Mushkegowuk Culture as described by the community members residing in Moose Factory, Intergenerational Impacts on fragmented Culture as experienced in the recent past and/or today in Moose Factory, and, Protective Measures to ensure safety of youth residing in the community. Themes expressed were built upon by a grounded theory providing direct knowledge based on the experience of the residents in Moose Factory. Overall it was discovered that introducing more culturally relevant programming and education could cease undesirable behaviours and assist with healthy life choices for future generations
Utilization of coal fly ash and grape waste to remove toxic metal ions in mining waste waters
Get PDFIn recent years, the studies of a variety of inexpensive adsorbents as alternative to the
expensive activated carbon have received a lot of attention. The purpose of my research was
primarily focused on the modification of Thunder Bay coal fly ash, the characterization of the
pristine and modified fly ash and the application of modified fly ash for removal of metal ions
from mine wastewater. Adsorption by grape wine material (GWM) was also investigated though
not completed. Modification at low and elevated temperatures with 2.0 M NaOH yielded improvement in
surface area, pore volume and cation exchange capacity. However, low-temperature modification
was pursued leading to very efficient adsorbents named TBRM and TBFZ compared to the original
fly ash named TB. The modified and unmodified fly ash was characterized using different
techniques including ICP-OES, X-ray diffraction, specific surface analysis (Brunauer-Emmet-
Teller), particle size distribution analysis and scanning electron microscopy. Surface area analysis
revealed an increase of specific surface area from 1.24 (TB) to 64.34 (TBRM) and 68.98 (TBFZ)
m2/g, respectively. Likewise, porosity was also induced in the modified fly ash. Cation exchange
capacities were determined as 1.94, 23.48 and 29.23 meq/g for TB, TBRM and TBFZ,
respectively. SEM-EDS and XPS were employed to confirm the adsorption of metal cations on
the surface of the adsorbents. The performance of TBRM and TBFZ for the removal of Cu2+, Pb2+, Ni2+, Cr3+, Co2+ and
Cd2+ from a synthetic cocktail solution (SCS) and tailing pond water (TPW) was compared to that
of TB. Results indicated TBRM and TBFZ were more efficient in both SCS and TPW. A batch
method was used to study the influential parameters of the adsorption process including contact
time, pH effect, and kinetics and adsorption isotherms. Column studies were done to compliment
the batch mode approach. Regeneration of TBFZ revealed a possible 3-cycle application. The equilibrium data were generally modeled by the Langmuir and Freundlich models.
Also, the pseudo-second order model was found to explain the adsorption kinetics most effectively.
Thermodynamic studies of Ni2+ and Cu2+ with TBFZ in SCS revealed that the adsorption process
was spontaneous although endothermic with a decrease in entropy. The most efficient adsorbent TBFZ was converted into innovative concrete foam composite
material TBFZ:FA:BA 0.22:0.33:0.45, for adsorption studies. Preliminary studies revealed a
removal of more than 95 % of Cu2+, Pb2+, Ni2+, Cr3+, Co2+ and Cd2 in both SCS and TPW after 6
h of contact. However, the regeneration of TBFZ:FA:BA 0.22:0.33:0.45 was inefficient and
further investigation ought to be carried out.
Overall, the results indicate a significant potential of the modified Thunder Bay fly ash as
an inexpensive and effective adsorbent for the removal of toxic metals from mine wastewater