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Parallel Stochastic Context-Free Grammar Training For Trna Secondary Structure Prediction., Kaiyuan. Shi
Parallel Stochastic Context-Free Grammar Training For Trna Secondary Structure Prediction., Kaiyuan. Shi
Electronic Theses and Dissertations
In this thesis, parallel computing methods are used to construct a stochastic context-free grammar for analyzing the secondary structure of tRNA molecules. Stochastic context-free grammars are basically probabilistic languages that parse a sequence/molecule and output its probability of whether or not it belongs to the sequence family modeled by the grammar and at the same time predict the molecule's secondary structure. Stochastic context-free grammars can be converted from corresponding context-free grammars, by assigning probabilities to the grammar's production rules. The use of stochastic context-free grammars to analyze the secondary structure of RNA molecules was limited due to time and space …
The Relationship Between Anthropogenic Disturbance And The Distribution Of A Nonindigenous Species, Echinogammarus Ischnus Stebbing, 1898 (Amphipoda: Gammaridae), At Great Lakes Coastal Margins, Misun Kang
Electronic Theses and Dissertations
Invasive species are becoming increasingly common components of Great Lakes zoobenthic communities. Elton (1958) proposed that biotic resistance against exotic species establishment is greater in intact communities than in those disturbed by human activities. However, Baltz and Moyle (1993) suggested that if abiotic conditions are appropriate, invasion is likely, regardless of the biota already present. I tested these hypotheses by investigating the distribution of Echinogammarus ischnus Stebbing, 1898, an exotic amphipod, at U.S. Great Lakes coastal margin sites influenced by varying degrees of anthropogenic stress. Thirty-nine sites supporting Gammarus fasciatus Say, 1818, a common amphipod with habitat preferences similar to …
Propagule Pressure: A Null Model For Biological Invasions., Robert I. Colautti
Propagule Pressure: A Null Model For Biological Invasions., Robert I. Colautti
Electronic Theses and Dissertations
I begin with a review of recent attempts to identify characteristics of species 'invasiveness' (i.e., the ability to invade) and habitat 'invasibility' (i.e., the susceptibility to invasion), and find little support for an emerging consensus on species- or habitat-specific characteristics. Moreover, I find that few studies consider hypotheses based on the concept of 'propagule pressure' (i.e., introduction effort), despite its potential as a confounding factor. Another barrier to generalizations may be the divergent use of operationally important terms like 'invasive', 'naturalized', or 'nuisance'. I therefore introduce a framework that conceptualizes biological invasions as a series of obligatory stages. This stage-based …
Factors Regulating Biomass And Contaminant Uptake By Round Gobies (Neogobius Melanostomus) In Western Lake Erie., Victoria Ann. Lee
Factors Regulating Biomass And Contaminant Uptake By Round Gobies (Neogobius Melanostomus) In Western Lake Erie., Victoria Ann. Lee
Electronic Theses and Dissertations
Round gobies, an invasive fish from the Ponto-Caspian region of Eastern Europe arrived in the western basin of Lake Erie in 1993. A bioenergetics model was developed for round gobies to quantify the flow of energy and contaminants from the benthos to pelagic fishes. Weight and temperature dependent coefficients for metabolism and consumption were derived. Food consumption increased with temperature up to 26°C before sharply decreasing and decreased with increasing fish weight. Oxygen consumption was inversely related to body mass and increased exponentially with temperature. Additional parameters were obtained from the literature to describe specific dynamic action, egestion and excretion. …
Zoobenthic Succession In Constructed Wetlands Of The Fort Mcmurray Oil Sands Region: Developing A Measure Of Zoobenthic Recovery (Alberta)., Christel Lynn. Leonhardt
Zoobenthic Succession In Constructed Wetlands Of The Fort Mcmurray Oil Sands Region: Developing A Measure Of Zoobenthic Recovery (Alberta)., Christel Lynn. Leonhardt
Electronic Theses and Dissertations
This study investigated the effect of oil sands process material (OSPM) on the zoobenthic community of constructed wetlands in the Fort McMurray oil sands region. The unique characteristics of OSPM-affected wetlands may modify the successional trajectory of invertebrate communities compared to that of high or low-conductivity reference wetlands. The zoobenthic community of 31 wetlands, aged 0 to 30 years, was simultaneously sampled, allowing inference into the chronological sequence of change that results with wetland succession. Wetlands were categorised a priori into one of three classes: low conductivity (<700 muS/cm) or high conductivity (700--2,500 muS/cm) reference wetlands or OSPM-affected wetlands (700--4,000 muS/cm) containing tailings and/or water from bitumen extraction. Invertebrate communities in each wetland were assessed using core, artificial substrate, and sweep net sampling methods. Principal components analysis and discriminant function analysis were used to classify each OSPM-affected wetland as being "equivalent to young" or "equivalent to mature" reference wetlands. Restoration of mined areas to pre-mining conditions of diversity and abundance of habitat types, using wetlands as a component of a reclamation strategy, is a viable option. (Abstract shortened by UMI.)Dept. of Biological Sciences. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2003 .L46. Source: Masters Abstracts International, Volume: 42-02, page: 0520. Adviser: J. H. Ciborowski. Thesis (M.Sc.)--University of Windsor (Canada), 2003.
Primary Production And Phytoplankton Dynamics In Western Lake Erie., Mark Alan John. Fitzpatrick
Primary Production And Phytoplankton Dynamics In Western Lake Erie., Mark Alan John. Fitzpatrick
Electronic Theses and Dissertations
Primary production studies have had a profound impact on the management of the Great Lakes, culminating with the Great Lakes Water Quality Agreement of 1972 between Canada and the United States. The current study examined primary production and phytoplankton dynamics in western Lake Erie with application to water quality and fisheries management practices. Annual primary production, estimated using a 14carbon tracer and both in situ and constant light incubations, ranged from 320--370 g C m-2 y-1 during the study period and was similar to the 340 g C m-2 y -1 reported in the basin for 1970. Phytoplankton standing crop, …
Effects Of Land-Use Patterns And Land Ownership On Biodiversity In The Natural Areas Of The Niagara Escarpment World Biosphere Reserve (Ontario)., Rosamonde Ellen. Page
Effects Of Land-Use Patterns And Land Ownership On Biodiversity In The Natural Areas Of The Niagara Escarpment World Biosphere Reserve (Ontario)., Rosamonde Ellen. Page
Electronic Theses and Dissertations
Existing under the protection of provincial legislation, the natural areas and biodiversity of the Niagara Escarpment World Biosphere Reserve have been particularly well-studied. I mapped land ownership and land-use patterns in the land matrix surrounding each of the 98 designated natural areas of the Reserve area, and then analysed their effects on estimates of biodiversity. Increasing percentages of recreational land-use surrounding a natural area were associated with degradative effects on rare plant species, as well as species with endangered or threatened status. Numbers of provincially rare plant species and endangered or threatened species were positively related to increasing amounts of …
The Impacts Of Polycyclic Aromatic Hydrocarbons On Brown Bullhead (Ameiurus Nebulosus) Apoptosis Regulation., Christopher Ronald Lindholm Busch
The Impacts Of Polycyclic Aromatic Hydrocarbons On Brown Bullhead (Ameiurus Nebulosus) Apoptosis Regulation., Christopher Ronald Lindholm Busch
Electronic Theses and Dissertations
In this study, it is hypothesized that the apoptotic pathways in the brown bullhead are altered by the presence of PAHs with a final outcome of elevated tumor formation. To evaluate the impact of PAHs on the apoptotic process, three separate, but related, studies were completed to characterise apoptosis in brown bullhead. First, the impact of known apoptotic inducers (staurosporine, cycloheximide, and TNF-alpha) on cell death in brown bullhead fibroblasts was characterized (Chapter 1). Secondly, fibroblasts were exposed to PAHs to examine how exposure to an environmentally relevant genotoxic substance alters the apoptotic pathway (Chapter 2). Finally, bullheads from various …
An Electro-Olfactogram Investigation Of The Responses Of Female Round Gobies (Neogobius Melanostomus) To Conspecific Odours And Putative Sex Pheromones., Andrea Jane Belanger
An Electro-Olfactogram Investigation Of The Responses Of Female Round Gobies (Neogobius Melanostomus) To Conspecific Odours And Putative Sex Pheromones., Andrea Jane Belanger
Electronic Theses and Dissertations
The round goby is an aggressive and prolific bottom dwelling fish species that threatens native economically and ecologically important fish in the Great Lakes. Its reproductive success may be mediated by the use of sex pheromones, with males attracting reproductive females to nests for spawning. As steroids have repeatedly been shown to function as conspecific signalling molecules (pheromones) mediating reproductive processes in teleosts, round goby males may release specific steroidal compounds to function as attractants to reproductive females. In this study, measurement of olfactory epithelial activity through electrolfactogram (EOG) analysis has shown that odors released by reproductive round goby males …
Enhancing The Yield Of Target Tissue And Secondary Metabolites In Calendula Officinalis L., A Medicinal Plant., Christie Lynn. Stewart
Enhancing The Yield Of Target Tissue And Secondary Metabolites In Calendula Officinalis L., A Medicinal Plant., Christie Lynn. Stewart
Electronic Theses and Dissertations
Medicinal crops can be usefully studied in controlled hydroponic systems in which various factors can be manipulated to increase target plant tissue yield and secondary metabolite production. In this project floral tissue and other plant organs of the medicinal plant Calendula officinalis and four important secondary metabolites: quercetin, rutin, isorhamnetin-3-O-glucoside and isorhamnetin-3-rutinoside were quantified under contrasting conditions in terms of phosphorus concentration, rate of nutrient supply and simulated foliar herbivory in a factorial experimental design. The objectives were to identify conditions that will maximize the yield of target plant tissue, maximize the production of secondary metabolites and minimize the variation …