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The effects of climate on the bioaccumulation of mercury in two large-bodied fish species in northern Ontario lakes
No full textIncreasing temperatures and changing precipitation patterns in subarctic Canada are expected to alter many processes in aquatic ecosystems, including mercury bioaccumulation in fish. I investigated patterns of fish mercury concentrations across the current climatic gradient in Ontario in order to assess how future climate change might impact the provisioning of safe fish. Walleye and white sucker were sampled from 70 lakes throughout northern Ontario spanning over 9.0° of latitude and representing a range of climatic conditions (annual growing degree days 604-1599). Muscle total mercury concentrations ([tHg]) were analyzed with respect to climatic variables as well as other chemical, physical, and biological variables. Second order Akaike Information Criterion (AICc) model ranking indicated that neither temperature nor precipitation were dominant drivers of mercury accumulation in walleye or white sucker. Instead, lake and watershed physical structure and δ13C best predicted white sucker [tHg], while water chemistry and fish condition best predicted walleye [tHg]. Specifically, walleye [tHg] showed a curvilinear pattern when related to [SO4] and [DOC]. The inhibitory effect of high lake [SO4] on mercury accumulation in fish has, to the best of my knowledge, only been theorised. Although fish mercury accumulation is not strongly driven by the current climatic conditions, a changing climate may indirectly affect mercury availability, methylmercury production, and the rate of methylmercury assimilation into fish tissue in ways that are not yet clear to us
Aerial image segmentation
No full textImage segmentation plays a vital role in applications such as remote sensing. For this example,
remote sensing, aerial image segmentation is a special case of image segmentation. There are
some unique features of aerial images, like noise in natural landscapes, which need to be
addressed in order to obtain an optimal solution. Bushes and rocks are examples of landscape
features with diverse and variable pixel values that need to be distinguished by the segmentation
process. Smoothing filters present a common solution to address the problem of noise in images,
as does aerial image segmentation. There are several image segmentation techniques used for
aerial image segmentation. Some of these techniques are more sensitive to noise problems, and
are necessary to discriminate between different smoothing filters. In this thesis, a number of
different aspects of aerial image segmentation and their solutions are explained. In addition to
this, a novel smoothing filter is introduced and compared with other methods using different
segmentation techniques. Finally, all of the previous points are applied to a real world problem
Efficient, robust surface functionalization and stabilization of gold nanorods with quaternary ammonium-containing ionomers as multidentate macromolecular ligands
No full textSurface functionalization of gold nanorods (GNRs) is critical to their applications in various
fields. While there are several existing strategies, we report in this article a new general strategy
for the surface functionalization of GNRs with quaternary ammonium-containing ionomers as a
novel class of multidentate macromolecular surface ligands. A range of tetralkylammoniumcontaining
hyperbranched polyethylene- and linear poly(n-butyl acrylate)-based ionomers has
been specifically designed and employed in the strategy. Acting as multidentate macromolecular
analogues of cetyltrimethylammonium bromide (CTAB), the ionomers have been demonstrated
to bind onto the GNR surface by displacing the surface-bound CTAB species via ligand
exchange to render CTAB-free ionomer-modified GNRs. By properly designing the enabling
ionomers, we have shown that the modified GNRs can be endowed with some desired properties,
such as excellent dispersibility in various organic solvents, robust stability under multiple rounds
(up to 12 investigated) of high-speed centrifugation in organic solvents, amphiphilicity with
dispersibility in both aqueous and organic media, fluorescence, and capability in carrying
hydrophobic guest species. This strategy thus provides potential new ways for the construction of
novel multifunctional GNR nanocomposites
Characterizing long non‐coding RNA at the DBF4 gene locus
Get PDFProper regulation of the cell cycle is essential for genetic stability and function. Mutations resulting in deregulation of the cell cycle are attributable to the development of diseases such as cancer. A large portion of the proteins responsible for regulating the cell cycle are found at DNA replication origins making replication origins an attractive target of research. Our lab has previously characterized a replication origin found in the promoter region of the human DBF4 locus which contains two zones at which two Origin Recognition Complexes bind and initiate replication in opposite directions in a specific manner termed Asymmetrical Bidirectional Replication. Within these same zones, our lab has also discovered the presence of transcription start sites for long non-coding RNA (lncRNA) transcripts. We’ve found that these non-coding transcripts are differentially transcribed from their neighboring genes and are resistant to RNA polymerase I, II and III inhibition. Results from these studies unexpectedly indicate the possibility of the mitochondrial RNA polymerase acting in the nucleus to transcribe the lncRNAs at the DBF4 locus. These transcripts are also cyclically more stably expressed than the DBF4 gene while retaining a relatively short half-life.
In an attempt to achieve a broader understanding of the replication process, the work in this thesis presents an effort to characterize and identify these lncRNAs initiating in the DBF4 promoter region and provide new insights into their behavior
Youth perceptions on anti-texting and driving advertisements: an eye-tracking approach
No full textTexting and driving has become a prevalent public health issue, especially in youth. The current
study recorded eye movements of young adults to texting and driving prevention advertisements
to determine the format that attracted the most attention. Thirty-three participants (Mean age 19)
viewed three types of advertisements (non-driving related, general distracted driving and texting
and driving specific) with three types of contents (text only, image only and text and image)
while their eye movements were recorded. Participants also completed a survey evaluating their
self-reported texting and driving behaviours. When comparing eye-tracking results for
participants who self-report texting and driving with those who do not, no significant differences
were observed. Results revealed an interaction of the types of advertisements and types of
content on dwell time. More precisely, when ads comprised text only, participants spent more
time viewing the texting and driving ads than the other types. For the texting and driving ads,
participants spent more time viewing when they comprised text only and, more time when they
comprised image only than both image and text. Regardless of the type of ads, when ads
comprised both text and image, participants spent more time viewing the images than the text. Since viewing behaviour did vary whether participants text and drive or not, results do not
provide clues to produce more effective ads for the target audience. Nevertheless, results suggest
that in order to influence young adult’s attention to texting and driving prevention
advertisements, text-only display would be preferable
Le choc culturel dans les relations parents-écoles au sein des familles immigrantes franco-africaines
No full textL’image de la société canadienne et ontarienne est plus diversifiée que jamais. Les immigrants viennent de partout au monde. Par ce fait, les écoles de langues françaises de l’Ontario augmentent le nombre d’élèves issus de l’immigration continuellement.
Ce mémoire jette une lumière sur les relations entre les parents immigrants franco-africains issus d’une culture plus traditionnelle et l’école ontarienne issue d’une société de culture plus moderne.
Par une approche qualitative comme démarche méthodologique, les résultats issus des entrevues semi-dirigées menées auprès des parents ont révélé une série de contraintes dues aux différences culturelles.
Ces contraintes, qui viennent teinter les relations entre les parents immigrants franco-africains et l’école ontarienne fréquentée par leurs enfants, sont regroupées en quatre catégories : les difficultés de compréhension du langage dans la communication, les difficultés de collaboration à la participation, les difficultés dans l’accompagnement scolaire des enfants à la maison et les difficultés dans l’implication des parents comme bénévoles dans les activités organisées par l’école.Maîtrise en Service Socia
Analysis of the effects of short-term subaerial weathering in different environmental conditions on bone colour and microstructure.
No full textThis preliminary study was conducted in order to evaluate the effect of subaerial environmental factors on bone colour change over time, and to quantify this using photography and Photoshop© CMYK analysis, as well with the Munsell Soil Colour Chart®. Additionally, surface microstructural changes with macroscopic and scanning electron microscopic (SEM) analysis were also conducted. Environmental data were tracked, and vapour density was documented and compared to relative humidity to determine the best-suited unit of measurement. The specimens consisted of 23 fleshed Sus scrofa humeri that were exposed to different microenvironments with varying sustrates and sunlight exposure. Although no discernable colour change trends were observed, other taphonomic changes were visible macroscopically in as little as 6 weeks to a few months of environmental exposure, and detailed distinctions could be made between specimens of different groups using SEM analysis
Life stories: an examination of some narratives of four men serving a life sentence
No full textIn 1976, the death sentence was abolished and replaced with mandatory life sentences with specified minimum periods for parole eligibility for those charged with murder. Although many lifers (those serving a life sentence) are released upon reaching their parole eligibility date they spend the rest of their lives under supervision and they face the prospect of being returned to prison for a violation of parole conditions. The notion of ‘serving time’ takes on a different dimension for lifers than it does for other offenders.
In this study I interviewed four lifers and applied a grounded-theory research approach to the analysis of their transcripts. The systemic violence they endured contributed to a sense of hyper-vigilance which became inscribed in their persons and persisted in their post-prison demeanour. Their prison experience was tantamount to a limit-experience (a type of action or experience with approaches the edge of living in terms of its intensity and its seeming impossibility) and it is the difference derived from this experience that is one thing that sets lifers apart from others in the community.
Inside, the prisoner learns to self-regulate his conduct in order to avoid punishment or have his behaviour read as normal but he also engages in overt and covert forms of resistance. Outside, the panoptic gaze has a powerful effect and self-regulation has become ingrained into the lifer’s being. Nonetheless all four of the
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participants talked with pride about their acts of resistance, even if the act was relatively insignificant.
All the participants talked insightfully about the meaning of time. Penal time becomes ‘time served’ and an instrument of disempowerment. The mind numbing, repetitious routines of institutional life eventually become ingrained into their being to the extent that they can hardly conceive of any other manner of existence. Consequently reintegration for lifers is fraught with effects of time served and even the most successful of the participants reported he could never shake the ravages of ‘time in’.
Ricoeurian theory and the use of narratives firmly anchors this thesis in the disciplines of the humanities. Narrative is a way of understanding life as it is lived. The use of narratives provides a means of gaining an in depth understanding of the lives of these participants and how the various dimensions of the life sentence have shaped their identities over time, while serving time
Interaction between virtual (computer gaming) environments, brain activity, and the Schumann resonance as the next evolutionary step in adaptation: Teilhard de Chardin's noosphere.
No full textThe interactions between the brain of the participant and the temporal flow of events within computer games could reflect a new type of consciousness-machine interface that could reveal novel options for biological-electronic evolution. The flow state which is defined as an inclusive, immersed affect state can be considered a component of and contribution to the interface computer (machine) simulations of real life events. Complex analyses during interactive gaming revealed two parent clusters of topographical quantitative electroencephalographic activity (QEEG) that emphasized the two cerebral hemispheres. A conspicuous peak around 40 Hz (25 ms) occurred upon the declining power gradient of cerebral output. The interactive flow state was more involved with right caudal hemispheric activations within relatively narrow frequency bands that overlapped with the earth-ionospheric Schumann resonances which are also found with normal spectral densities of QEEGs. Independent Component Analyses and Linear Discriminant Analyses for components of QEEG during reward and skill segments of computer game involvement verified the importance of the duration of a percept (around 130 ms). The results were consistent with the possibility that two successive percepts, one of them preceding awareness, might be influenced by extracerebral factors strongly correlated with Schumann Resonance properties. When two experienced or non-experienced gamers shared the same circumcerebral magnetic fields with 20 to 25 ms phase modulations as a second derivative, evidence of excessive correlation, the basis of entanglement, was evident. Application of these results and integration with a biological theory developed by Teilhard de Chardin that the next stage of evolution involve the “noosphere” within which collective experiences would direct subsequent developments in life suggest the feasibility is much greater than previously anticipated
Employing heat pumps to recover low grade industrial thermal resources for space heating and cooling
Get PDFThe use of heat pumps to upgrade and recover low grade industrial thermal resources is an opportunity for industry to deliver low cost space heating at a reduced carbon footprint. Heat pumps also offer the potential to provide space heating and space cooling from a single unit. To facilitate rapid determination of the potential for low grade heat recovery using ground source heat pumps, a rapid scoping method was developed capable of establishing critical temperatures to help elucidate which resources are most likely to be recovered economically. To demonstrate the applicability of the rapid scoping method, an analysis of various process cooling waters present at a smelter site was undertaken. The implications for cost and carbon dioxide emissions, were both analyzed for this facility, although the concepts developed can be employed to any site that generates large quantities of thermally low-grade heat