Digital Commons Network^™

Quantifying Cognitive Function In Concussed Athletes Before And After Acute Exercise Using A Choice Reaction Time Task, Stephanie A. Ramautar M.Sc., Michael E. Cinelli Ph.D.

Theses and Dissertations (Comprehensive)

Following a concussion, cognitive deficits have been shown to last longer than symptom resolution. Currently clinicians rely heavily on symptom emergence following the fundamental exercises of the return to play (RTP) protocol, which may leave athletes at risk of returning to play too early if cognitive deficits have not been detected. The purpose of this study was to assess the effects of exercise on choice reaction time (CRT) both at rest and following an acute exercise in 3 populations: non-concussed (NC), recently concussed (RC), and post-concussion syndrome (PCS) individuals. A CRT task in the form of an iPad application measured …

Laterality Across The Lifespan: The Effects Of Task Complexity, Nicole Williams

Theses and Dissertations (Comprehensive)

The current study aimed to build on the work of Gooderham & Bryden (2013) by comparing the effects of task complexity on hand selection across the lifespan. It was hypothesized that the increasing complexity of a task would override a biomechanically efficient movement such that participants would use only the preferred hand to complete the task. It was also hypothesized that older adults would perform similarly to young children with respect to switch points in space. Four age groups of participants (3-7 year olds, 8-12 year olds, 18-25 year olds and adults over 70 years) completed the newly designed Hand …

Gait Initiation Mechanics In Concussed Varsity Athletes, Adam Harper

Theses and Dissertations (Comprehensive)

Concussions are a common and potentially serious injury that affects athletes across multiple sports. More than ever concussions are now at the forefront of sport-related research.

Current research indicates that in a cohort of Canadian junior hockey players examined during the 2009-2010 season showed a rate of concussion at 36.5% of all athletic injuries (Echlin et al., 2010). This rate of concussion injury indicates that proper evaluations and examination tools are key to successful management of concussions. The objective of this study was to determine whether a functional task such as gait initiation is able to quantify stability difference following …

An Exploratory Examination Of Families Engaged In An Adventure Running Kids Program, Heather Isnor

Theses and Dissertations (Comprehensive)

Academics and practitioners have only just begun to delve into the health benefits of outdoor activities in the last few years. In general, the forested settings of these activities have been documented to decrease stress levels, increase recovery rates from disease, and lessen the symptoms of mental illnesses (Kuo & Faber Taylor, 2004). It is believed that the natural environment acts as a setting where humans can engage in physical activity, aesthetic experiences, and social interactions that, in turn, release stress and lead to improved well-being (Bird, 2012). Currently, however, children are experiencing limited exposure to nature and which has …

Effects Of A Heart Rate Variability Biofeedback Intervention On Athletes’ Psychological Responses Following Injury, Andrew S. Rollo Mr.

Theses and Dissertations (Comprehensive)

The purpose of this study was to evaluate the effectiveness of heart rate variability biofeedback (HRV BFB), a form of psychophysiological skills intervention, to improve athletes’ psychological response following an injury. Further, to examine the effects of HRV BFB on self-efficacy, perceived stress and anxiety, pain management, and the psychological responses of injured athletes. HRV BFB effects on athletes’ physiological indices including HRV, HR, and respiration rate were also assessed. Participants were 32 athletes who had sustained a moderate to severe musculoskeletal sports injury, ranging in age from 18 to 36 years (M_age = 20.82, SD = 3.41). …

Physical Fitness Characteristics Of An Active Firefighter Population Serving An Urban Area, Michael R. Antolini

Theses and Dissertations (Comprehensive)

Firefighters require a high level of physical fitness in order to meet the demands of their profession. While physical fitness testing is required to join the department, firefighters are not subject to further formal exercise testing throughout the duration of their careers. Active, career firefighters were tested on a variety of physical fitness measures related to body composition, strength, power, and endurance over three testing sessions. 49 firefighters (40.5 ± 8.3 yr, 89.5 ± 13.0 kg, 27.8 ± 3.6 kg/m2) were found to have a resting heart rate of 57.7 ± 8.2 bpm, blood pressure of 121.5 ± 11.9/71.5 ± …

Investigating The Persistence And "Naturalization" Potential Of Salmonella In Non-Host Environments Using Culture-Based And Molecular-Based Fingerprinting Techniques, Robyn L. Morrison

Theses and Dissertations (Comprehensive)

Recent studies suggest the potential exists for enteric microorganisms to become “naturalized” to the complex natural environment through maintenance of their populations via replication and adaptation to the stress imposed by their external surroundings. The aim of this research was to better understand the potential for antimicrobial resistant (AMR) Salmonella to become “naturalized” and the physiological adaptations that allow for non-host survivability as reflected by AMR and community profiling. To better elucidate the prominent factors leading to a “naturalized” condition, two approaches were taken: 1) survey-based field research to gain perspective on the prevalence of AMR Salmonella isolated from variously …

Characterization Of The Transporter Protein Sodium-Potassium Adenosine Triphosphatase In The Myelin Membrane, Dara E C Schaefer

Theses and Dissertations (Comprehensive)

Sodium-potassium adenosine triphosphatase (Na⁺/K⁺-ATPase) is an integral membrane protein with known involvement in the maintenance of resting membrane potentials, nutrient uptake, cellular signal transduction, and cell-cell adhesion. The functional enzyme contains a catalytic alpha subunit and a glycosylated beta subunit, of which three isoforms of each are known to exist in the central nervous system (CNS). Altered expression and/or activity of Na⁺/K⁺-ATPase subunit isoforms has been previously implicated in the pathophysiology of several neurological disorders. This study characterized Na⁺/K⁺-ATPase expression and distribution in the myelin membrane, identified its …

Microbial Community Characterization And Pathogen Profiling Of Land-Based Aquaculture Systems Using Culture-Based And Molecular-Based Fingerprinting Techniques, Nicole S. Kteily

Theses and Dissertations (Comprehensive)

The growing worldwide demand for fish production has prompted research towards intensive aquaculture. Innovative system designs, such as recirculating and flow-through aquaculture systems, have been developed to improve the efficiency and sustainability of intensive aquaculture practices. These LBAS systems exhibit a wide range of spatial and temporal heterogeneity. Although such heterogeneity suggests the potential for culture water to support a diverse and spatially complex assortment of microorganisms, there is a lack of information regarding the overall diversity and composition of microbial communities (including pathogens) in the different compartments of these systems. To better understand the diversity and functionality of microbial …

The Lived Experiences Of Adult Siblings Of Individuals With Asd, Brianne Redquest

Theses and Dissertations (Comprehensive)

Autism Spectrum Disorders (ASD) are the most prevalent neurological and severe developmental disorder affecting 1 in 88 Canadians, reflecting a 78% increase over the last 6 years (Autism Speaks Canada, 2013). ASD is a lifelong disorder which requires a tremendous amount of support and caregiving from family members. As a result, siblings may have unique experiences associated with having a sibling with ASD. As such, the purpose of this study was to examine the lived experiences of adult siblings of individuals with ASD. The study employed a qualitative methodology, more specifically phenomenology (Patton, 2002). One-on-one semi-structured interviews were conducted with …

The Role Of Body Size On The Outcome Of Mating Interactions In Drosophila Melanogaster, Adam C. Lounsbury

Theses and Dissertations (Comprehensive)

Sexual selection is the process by which some individuals produce more and/or better quality offspring than others because they are better at securing mates. While this may be accomplished by defeating same-sex rivals (intrasexual selection), individuals of one sex (typically females) may also “decide” on the suitability of individuals of the opposite sex (typically males), resulting in intersexual selection on attractive traits. While a great deal of scrutiny has focused on how sexual selection influences male display traits, much less scrutiny has been directed toward the factors underlying female preference, including genetic variation, as well as the extent to which …

Characterizing Dsrna Production In Virus-Infected Fish Cells, Amal Brek Aloufi

Theses and Dissertations (Comprehensive)

Viral dsRNA is produced by almost all viruses sometime during their replicative cycle. These viral nucleic acids are potent inducers of both innate and adaptive immune responses, and are therefore considered important immuno-modulators. Previous studies have shown that viruses produce dsRNA when replicating in mammalian cells; however, to date no one has demonstrated viral dsRNA production in virus infected fish cells. Therefore, the goal of this study is to investigate dsRNA production by fish viruses in fish cells, verifying production and performing initial characterization of the dsRNA molecules being produced. Three different rainbow trout cell lines were used in this …

The Evolutionary Dynamics Of Transcription Factors, Operators, And Their Target Genes Across Prokaryotes, Marc Del Grande

Theses and Dissertations (Comprehensive)

In prokaryotes, transcriptional regulation commonly involves a transcription factor (TF) binding to a particular conserved sequence of nucleotides (operator). Binding elicits a transcriptional response, either activation or repression. The evolution of gene regulation has been identified as a primary driver of species diversity, making it an important area of research. This work examined the dynamics of the interactions between TFs and operators, and TFs and their primary target genes in attempt to assess the rapid evolution of transcriptional regulatory networks (TRNs) across a diverse set of prokaryotes. Using software packages, operator sequences from Escherichia coli K12 were compared to every …

Nesting Ecology Of White-Throated Sparrows (Zonotrichia Albicollis) : The Effects Of Variation In Clutch-Initiation Date And The Application Of Prescribed Fire On Nesting Success, Melissa Olmstead

Theses and Dissertations (Comprehensive)

The study of nesting success is one of the most widely-used methods for examining the factors governing recruitment in birds. Many ecological influences act together to increase or decrease nesting success, and knowledge of these mechanisms is crucial for determining the habitat or conservation requirements of a given species. One ecological influence is the timing of breeding, which in many species is related to a decline in nest success later in the breeding season. Much of the research on this subject has focused on cavity-nesting species, and the hypothesis that this seasonal decline is caused by a mismatch between clutch-initiation …

Distribution And Elimination Of 3-Trifluoromethyl-4-Nitrophenol (Tfm) By Sea Lamprey (Petromyzon Marinus) And Non-Target, Rainbow Trout (Oncorhynchus Mykiss) And Lake Sturgeon (Acipenser Fulvescens), Michael W. Le Clair

Theses and Dissertations (Comprehensive)

The pesticide, 3-trifluoromethyl-4-nitrophenol (TFM), has been highly successful in the control of sea lamprey (Petromyzon marinus) populations in the Great Lakes. Treatments with TFM involve applying it to streams, where it targets larval sea lamprey which live burrowed in the stream substrate. While the toxic mechanism of TFM has been elucidated, and its effects on sea lamprey described, its effects on non-target fish species such as rainbow trout (Oncorhynchus mykiss) and lake sturgeon (Acipenser fulvescens) are not as well understood. The present work demonstrated that rainbow trout show a great capacity to detoxify the lampricide using glucuronidation, when exposed to …

A Structure-Function Analysis Of The Arabidopsis Chloroplast Import Protein Attic20, James H. Campbell

Theses and Dissertations (Comprehensive)

Arabidopsis thaliana protein Tic20 (atTic20) is a member of the translocon at the inner envelope membrane of chloroplasts. Evidence to date suggests it is part of the main preprotein conducting aperture in the complex, but its exact role is still debated. To help characterize its role, a protocol optimizing yield and purity of recombinantly expressed atTic20 was developed, and a series of experiments was performed to examine its secondary structure and its ability to interact with chloroplast transit peptides. The attempt to increase protein yield was successful, with growth at 20^oC in the auto-inducing media ZYP-5052 showing the …

The Innate Antiviral Effects Of Extracellular Viral Dsrna In Rainbow Trout Cells, Sarah J. Poynter

Theses and Dissertations (Comprehensive)

Viral double-stranded RNA (dsRNA) molecules are a potent pathogen-associated molecular pattern and play a crucial role in the innate immune response. During a viral infection, extracellular and intracellular dsRNA can initiate pathways resulting in the production of type I interferons (IFNs) and interferon-stimulated genes (ISGs). The accumulation of ISGs within a cell results in a protective antiviral state. This study used both commercially available dsRNA (poly I:C) and in vitro transcribed dsRNA molecules, based on the viral hemorrhagic septicemia virus (VHSV) genome sequence, as stimuli to investigate the effects of these molecules on the innate immune response in rainbow trout …

A Bittersweet Investigation Of Availability And Nutritive Value As Determinants Of Volitional Sucrose Consumption, Milan D. Valyear

Theses and Dissertations (Comprehensive)

Rats given ~24 h access to a 4% sucrose solution every 3^rd day (E3DA) consume about 100 g more solution than rats with continuous, everyday access (EDA). Under the same EDA-E3DA conditions rats will consume similar amounts of a more concentrated 8 or 16% sucrose solutions (Eikelboom, Hewitt, & Adams, Unpublished). It maybe that with these more concentrated solutions rats hit a satiety limit that prevents a difference between EDA and E3DA consumption from being evident. Experiment 1 was conducted to investigate the effect of adding quinine to 4% and 8% sucrose solutions with the intention of reducing consumption …

Recovery From Acute Toluene Intoxication Is Facilitated By The Nmda Receptor Co-Agonist D-Serine, But Not The Gabaa Receptor Antagonist Picrotoxin, Susan R. Samuel-Herter

Theses and Dissertations (Comprehensive)

Toluene is a volatile solvent found in many household products and when intentionally inhaled results in intoxication. In rats, acute inhalation of toluene results in sedation and neurological impairments, with marked increases in ambulation and vertical behaviour during the recovery period. Previous in vitro research has shown that toluene may exert its effects by inhibiting NMDA receptors, and / or by activating GABA_A receptors. To test whether modulation of these receptors are also implicated in the changes in motor behaviour and neurological impairments resulting from toluene vapour inhalation, rats were injected with the NMDA receptor co-agonist D-serine (1000 mg/kg …

Comparative Analysis Of Selected Model Species Used In Intervertebral Disc Research, Lauren A. Monaco

Theses and Dissertations (Comprehensive)

Animal models are frequently used in place of human specimens to study the progression of injury and/or disease of the intervertebral disc (IVD). This project aimed to compare the geometry, hydration, histology, and mechanical properties of selected animal models: bovine (cow) tail, porcine (pig) lumbar, and ovine (sheep) lumbar IVDs. X-ray images were taken and used to determine the anterior, posterior, and lateral IVD and vertebral heights in order to calculate IVD: vertebral height ratios. Water content was determined by comparing IVD weight before (wet weight) and after (dry weight) 24 hours of incubation at 65°C. Mechanical properties …

Comparative Study Of Factors Influencing Seed Germination And Seedling Longevity In Cuscuta (Dodder, Convolvulaceae), Behrang Behdarvandi

Theses and Dissertations (Comprehensive)

Cuscuta (dodder), the only parasitic genus of Convolvulaceae family, is a significant plant from ecological, economical, and conservational point of views. The genus consists of c. 200 described species with wide ranges of ecological distributions. Cuscuta spp. are categorized as stem parasitic plants with reduced (or lost) photosynthesis-related genes. The filamentous coiled embryo, embedded in the endosperm, lacks cotyledons and is covered with a multiple-layered seed coat. The seedlings carry a vestigial root-like organ which is not considered a ‘true’ functional root. Members of the genus differ in their germination rate and seedling survival. It is known that seed …

Diversity And Evolution Of The Multicellular Protuberances In Cuscuta (Convolvulaceae) And The Function Of The Stomatiferous Protuberances In Cuscuta Subgenus Grammica, Courtney J. Clayson

Theses and Dissertations (Comprehensive)

Cuscuta (Convolvulaceae), also known as the dodders, is a holoparasitic genus comprised of ca. 200 species grouped into four subgenera: Monogynella, Cuscuta, Pachystigma, and Grammica. The presence of unique multicellular structures, referred to as stomatiferous protuberances (SPs), was reported on the stems of subgenus Grammica over a century ago and was forgotten until similar SPs were observed on the flowers of several new Grammica species. The stems and flowers were examined in 136 Cuscuta taxa, and SPs were discovered on all of the haustorial stems of the species in the subgenus Grammica, as well as …

Effects Of Salinity And Dissolved Organic Matter On Cu Toxicity To Americamysis Bahia In Estuarine Environments, Rabia Nasir

Theses and Dissertations (Comprehensive)

As salinity increases the geochemical speciation of Cu is altered as a result of organic/inorganic complexation/competition. Such salinity changes may further challenge the osmoregulatory capabilities of euryhaline organisms. This chemical-biological interaction complicates the understanding of the impacts of Cu in estuarine waters. Dissolved organic matter (DOM) has been widely established to be an important modifier of Cu toxicity in freshwaters however its effectiveness in modulating Cu toxicity across the range of salinities that occur in estuarine conditions has not been studied in a systematic manner. Site to site differences in DOM quality with respect to the potential for toxicity mitigation …

Musical Chairs In A Boreal Peatland: How Permafrost Thaw Reverses Successional Processes, Mélissa M. Fafard

Theses and Dissertations (Comprehensive)

The current climate trends indicate amplified high latitude warming. Boreal peatlands can be found within those high latitudes and have important functions hydrologically, ecologically and also in terms of carbon cycling. Peatland’s are wetlands that have accumulated more than 40 cm of peat and can range from minerotrophic fens to ombrotrophic bogs. Naturally, a rich fen can be converted to a bog once groundwater sources are cut off by Sphagnum spp. In areas underlain by discontinuous permafrost, landscape changes are occurring particularly rapidly as the permafrost there is sensitive to both vertical and horizontal thaw. The purpose of this thesis …

Causes And Consequences Of Female Mate Choice In Drosophila Melanogaster: A Hemiclonal Analysis, Hannah Me Tennant

Theses and Dissertations (Comprehensive)

One of Darwin’s greatest questions, the reason why females prefer elaborate sexually selected male traits and displays, was elucidated by the Fisherian coevolution of male traits and female preferences. While variation in male attractiveness and ornamentation has received much attention, there has been little attempt to evaluate the causes and consequences of intraspecific variation in components of female preference. Furthermore, demonstrating a genetic basis to female preference does not answer the question of how within-population genetic variation is maintained.

Understanding the sources of variation in potential mating interactions between males and females is important because this variation determines the strength …

Time, Perspectives, Verbs, And Imagining Events, Jeffrey P. Hong

Theses and Dissertations (Comprehensive)

During the processing of verbs, readers form internal representations of the events described by those verbs. Two key elements in the construction of event representations are temporal information, given by the verbs that describe the represented events, and the visual perspective from which the events are represented. The current study is composed of two experiments aimed at examining the roles these two factors play in event representation. Specifically, the study aimed to determine how temporal information and visual perspective are represented during event imagination.

Experiment 1 investigated the role of temporal information associated with verbs, given by grammatical aspect (GA) …

Genome Jigsaw: Implications Of 16s Ribosomal Rna Gene Fragment Position For Bacterial Species Identification, Jennifer Mitchell

Theses and Dissertations (Comprehensive)

The 16S rRNA gene is present within all bacteria, and contains nine variable regions interspersed within conserved regions of the gene. While conserved regions remain mostly constant over time, variable regions can be used for taxonomic identification purposes. Current methodologies for characterizing microbial communities, such as those used to study the human microbiome, involve sequencing short fragments of this ubiquitous gene, and comparing these fragments to reference sequences in databases to identify the microbes present. Traditionally, whole 16S rRNA sequences with more than 97% sequence identity (id) are assigned to a single operational taxonomic unit (OTUs); each OTU being a …

Zombies In Bacterial Genomes: Identification And Analysis Of Previously Virulent Phage, Scott Mitchell

Theses and Dissertations (Comprehensive)

Bacteriophage (or ‘phage’) are viruses that infect and reproduce within their bacterial hosts. They have a major global impact on bacterial evolution and ecology, and might influence the pathogenicity of their host bacterium by providing virulence factors. Phage can either be described as “virulent” or “temperate”; the distinguishing feature between the two is their method of replication.

This study sought to identify phage sequences within bacterial host genomes and determine the life cycle of the phage, exploring whether there is a connection between defective phage and previously virulent phage. It would normally be expected that any phage sequences identified within …

The Establishment Of A Fibroblastic Cell Line From Yellow Perch (Perca Flavescens) And Its Potential Applications In Toxicology, Katelin W. Spiteri

Theses and Dissertations (Comprehensive)

This thesis describes the establishment, characterization and potential toxicological applications of YPF5, a yellow perch cell line. YPF5 is a fibroblastic cell line derived from the caudal fin of yellow perch. This cell line has been maintained for over 2 years. Cultures have been passaged over 60 times, and successfully cryopreserved and thawed. YPF5 is grown at room temperature in Leibovitz-15 (L-15) media, supplemented with 10% fetal bovine serum and 3% penicillin-streptomycin. The origin of YPF5 has been confirmed as Perca flavescens through “DNA Barcoding” and reaffirmed through Karyotyping (2n = 48) as per literature reported karyology for percidae including …