Brock University Digital Repository
Brock University’s Digital Repository is an online archive showcasing and preserving the Brock community’s scholarly output as well as items from the Library’s Special Collections and Archives. Researchers can disseminate their work by depositing it in this Open Access repository, which provides free, immediate access to users while also allowing Brock scholars to track downloads and views of their scholarship.
For more information, see the repository's policies and procedures.
Share Your Work - Not sure where to start? Have Library Staff deposit your work on your behalf. Just fill in this form and we'll proceed on your behalf.
Self Submission - Deposit your paper or research material directly into the repository. Simply login with your Portal Information at this link and follow along.
Thesis Submission - If you need to submit your thesis to the repository to complete your graduation requirements you can do so here. Login with your Portal Information and fill in the form.
Communities in Brock University Digital Repository
Select a community to browse its collections.
Mixed Media in Evolutionary ArtThis thesis focuses on creating evolutionary art with genetic programming. The main goal of the system is to produce novel stylized images using mixed media. Mixed media on a canvas is the use of multiple artistic effects being used to produce interesting and new images. This approach uses a genetic program (GP) in which each individual in the population will represent their own unique solution. The evaluation method being used to determine the fitness of each individual will be direct colour matching of the GP canvas and target image. The secondary goal was to see how well different computer graphic techniques work together. In particular, bitmaps have not been studied much in evolutionary art. Results show a variety of unique solutions with the application of mixed media.
A Study on Immersion and Emotions’ Influence on Impulse Buying in Virtual EnvironmentsImpulse buying has always been an interesting phenomenon that is observed in our daily lives. Statistics have shown that impulse purchases make up almost 40% of all purchases made online. Many studies have examined impulse buying, and they have found that emotions accompany impulsive behaviors naturally. With the recent development in virtual reality (VR) technology, this phenomenon is observable in online virtual environments. Retailers can create immersive virtual shops where the customer can walk among the aisles of a virtual store and make purchases. This study examines whether the effects of emotions on impulse buying vary across different immersion levels (2D vs. VR) and gender. To test our hypotheses, we collected data from the 2D and VR setting using experiments. The results provide evidence that gender plays a significant role in the three-way relationship between positive/negative emotions, immersion, and impulse buying. The unique setting of our research extends the literature on impulse buying, marketing, and virtual reality. The results offer valuable insights to marketers and retailers who want to develop virtual shops and influence impulse buying in these virtual shops.
The Influence of Posttetanic Potentiation on Neuromuscular Efficiency in Mouse Fast Twitch Muscle at 25°CWithin skeletal muscle the release of calcium is responsible for the initiation of muscle contraction. In addition intracellular Ca2+ also induces the protein skeletal muscle myosin light-chain kinase (skMLCK) to phosphorylate the regulatory light chain (RLC) of fast myosin isoforms. For a short time following RLC-phosphorylation a potentiated state is induced within muscle fibres in which force generation and other contraction dynamics are augmented. The intent of our study was to examine the effect of tetanic stimulation (>100Hz) induced potentiation on the efficiency of neuromuscular contraction (Work output: # of Pulses). Concentric contractions were used in which muscles shortened 1.10 -> 0.90 Lo, at ~70% maximal shortening velocity (Vmax). The fast twitch extensor digitorum longus muscles were excised and mounted in vitro (25oC) to examine the effect of NME on whole muscle function. Unique to our lab were the use of skMLCK-/- mice which are unable to phosphorylate their myosin-RLC, and thus display no magnitude of posttetanic potentiation. These models were used as a negative control for potentiation compared to the wild type EDL. NME was tested during series of submaximal tetani at five frequencies (10, 25, 40, 55, 80 Hz) before and after muscles were exposed to the conditioning stimulus (4 x 400 msec, 100 Hz, over 10 seconds). Neuromuscular efficiency was found to be increased at all frequencies for both wild type (P<0.001) and skMLCK-/- (P<0.002) genotypes following the CS (n=12). NME potentiation was significantly impacted by the expression of skMLCK and test frequency. At optimal frequency wild type EDLs displayed a 92% increased relative NME compared to the 33% seen in the skMLCK-/- genotype showing the importance of RLC-phosphorylation to contractile enhancement. Work values preceding the CS were not significantly different at any frequency in either genotype (P = 0.236). The presence of RLC phosphorylation is physiologically significant in enhancing force output as well as improving neuromuscular efficiency following PTP.
The Effect of Muscle Length on Post-Tetanic Potentiation of skMLCK-/- and C57BL/6 Mouse EDL MusclesPost-tetanic potentiation of force in fast skeletal muscle is inversely related to muscle or sarcomere length, diminishing at longer lengths. This relationship has been mainly attributed to the structural effects of the primary mechanism of potentiation, phosphorylation of the regulatory light chain (RLC) of myosin, which is catalyzed by skeletal myosin light chain kinase (skMLCK). The purpose of this thesis was to compare the relationship between isometric twitch force potentiation and muscle or sarcomere length in fast twitch extensor digitorum longus (EDL) muscles from wildtype and skMLCK-/- mice. It was hypothesized that in addition to reduced potentiation, skMLCK-/- muscles without the ability to phosphorylate the RLC would also display an altered length-dependence of potentiation compared to wildtype muscles with RLC phosphorylation. The main finding was that although twitch potentiation was greater in WT muscles at all lengths, the relationship between potentiation and muscle length was similar in both WT and skMLCK-/- muscles. This indicates that the length-dependence of potentiation cannot necessarily be attributed to RLC phosphorylation. Thus, additional mechanisms, possibly related to Ca2+ handling, thick filament mechanosensing and length-dependent activation may participate in the length-dependence of potentiation displayed by murine fast muscle models.
Exploring Parental Experiences and Meaning of Involvement within Youth Sport: An Interpretative Phenomenological AnalysisBy applying an interpretative phenomenological analysis approach, the purpose of the study was to explore the lived experience of parental involvement in youth sport and the meaning the involvement holds. Specifically, I wanted to examine how role identity theory can provide deeper understanding to how parents experience and provide meaning to their involvement in their children’s sport. A key aspect to the study is that as the researcher, I was attempting to understand the experiences of the participant’s meaning-making. Master themes that capture the overall phenomenon were constructed that were present across the majority of participants while still allowing for each participant’s unique experience to be understood. The overarching themes interpreted from the data include: Desiring Involvement, Onus on Parental Roles within Involvement, Commitment, and Constructing Meaning-making of the Experience. These findings highlight the ways in which role identity salience defines the experience and the meaning involvement holds to a parent. This study provided deeper theoretical understanding of the experience of being a parent involved in youth sport, as well as highlighted the usefulness of conducting research in this field with an interpretative phenomenological analysis approach to explore a complex and diverse topic.