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White-Lind fonds, 1844-1964, n.d.
Get PDFHannah Jane Lind and John G. White were married in 1883 in Caistor Township, Ontario. They had a daughter, Ruby, and a son, Stanley. In 1914 their son Stanley George White married Irene Janet Henderson in Wentworth, Ontario. They lived on a fruit farm in Winona that later became a section of the Queen Elizabeth Way. In 1957 they sold the farm and moved to Grimsby. They had daughter, Helen, and a son, Gordon.Fonds contains material related to the White and Lind families. Most of the fonds consists of photographs with some correspondence, news clippings, and ephemera, and is focused on Hannah Lind White & John White, and Irene Henderson White & Stanley White. There are also two letters addressed to William and John Lind from 1844 and 1845. The material was kept in the order it was received with the assigned labels
Properties of a flexible visual short-term memory resource
Get PDFFor the last few decades, there has been considerable debate as to whether visual short-term memory (VSTM), the capacity limited memory system for the short-term storage of visual information, is a continuous or discrete resource. One property that has been identified that is consistent with a continuous resource is flexible allocation; in a delayed- recall task, when cues manipulate the priority (task relevance) of the sample items to decouple resource allocation from set-size, performance has been found to vary with the proportion of allocated resources. However, the extent and limits of this property have yet to be identified. Moreover, discrete resources could account for some previous findings through probabilistic encoding. The current thesis aimed to examine the properties and limits of flexible resource allocation in VSTM. In Chapter 2, I examined whether VSTM resources could be allocated to three levels of attentional priority. Although possible, examining individual differences in the strategies participants used revealed that the majority of participants do not use all three priority levels. Chapter 3 investigated an alternative resource allocation strategy, whereby the strategic use of a discrete memory resource to store the most relevant memory items would be encoded probabilistically. Response precision better matched predictions of flexible allocation. Further, I directly tested probabilistic encoding by estimating the proportion of “in-memory responses” and comparing it with individuals’ estimated capacity. Results again did not support a probabilistic encoding strategy. A criticism of flexible allocation is that very low precision memories are indistinguishable from out-of-memory responses. In Chapter 4, I examined flexible allocation using a two alternative forced choice (2AFC) task intermixed with continuous response trials, as 2AFC can show evidence of weak memory through better-than-chance recognition performance. Results demonstrated that participants performed better than chance for very low-priority items. This suggests that these items are stored as low-resolution memory representations, rather than being out of memory altogether. Collectively, these studies reveal properties of a flexible VSTM resource. Taken together, these data further suggest that any model that cannot accommodate a dynamic, flexible resource should be abandoned
Effects of Space Restrictions and Mouse Locations on Upper Extremity Kinematics and Muscle Activity during Computer Tasks
Get PDFPeople spend an average of 37.5 hours/week on their computers, totalling 1800 hours annually (Noack-Cooper, K. L. et al., 2009). Spending >4 hours daily on a computer demonstrates increased MSD risk, such as carpal tunnel syndrome (Ardahan, M., & Simsek, H., 2016; Manktelow, R. T. et al., 2004). Work-from-home scenarios can lead to make-shift workstations, with space restrictions. The purpose of this work was to quantify upper extremity muscle activity and posture during computer tasks, when people are exposed to restricted environments. 18 healthy university-aged participants (8 Male, 10 Female) were recruited. Participants were outfitted with surface electromyography on 16 muscles of the trunk/right upper extremity, and 13 reflective motion capture markers. Two mouse-based tasks were completed using AimLab: 1) a point-and-click task, and 2) a mouse tracing task. Tasks were completed in four common mouse locations in both restricted and unrestricted boundaries. Supraspinatus, upper trapezius, and middle trapezius demonstrated significant increases in muscle activity between both tasks. Right middle (SUPR: 64.1 ± 17.2 %MVE; UPTR: 3.5 ± 0.8 %MVE; MTRP: 12.9 ± 4.4 %MVE), and front keyboard (SUPR: 71.5 ± 19.6 %MVE; UPTR: 3.5 ± 0.7 %MVE; MTRP: 16.0 ± 5.3 %MVE) locations produced the greatest amount of muscle activity in both conditions. Restricted conditions across locations increased joint angles across the shoulder, elbow, and wrist joints. Lateral and deep mouse locations created increased shoulder extension and abduction across both conditions. Participant accuracy was greater in the restricted conditions (PC: 96 ± 5.3%; Track: 84.9 ± 10.7%) compared to unrestricted (PC: 95.4 ± 5.8%; Track: 81.4 ± 8.9%). Increases in muscle activity were found across all locations and conditions for the shoulders and upper back, with the restricted condition demonstrating the greatest increase in activity. This could suggest that increased discomfort and musculoskeletal complaints are probable when working in a restricted environment for extended periods of time. Utilizing the front edge of the desk as a mouse location decreased muscle activity, which may provide rest of relief from muscle overuse
Academic Competition in the School System: At What Cost?
Get PDFCompetition pervades our culture across sports, entertainment, politics, and corporations, seeping also into educational institutions. Today, children are urged not only to "play to win" but also to "learn to win." Despite awareness of competition's negative psychological and social impacts, it remains a cornerstone of the educational system as it is perceived as a strong motivating factor for academic achievement. However, academic competition has received less attention than its athletic and social counterparts, with previous research often overlooking its effects on interpersonal relationships. Existing studies have either used inappropriate measures for academic settings or failed to differentiate between other-referenced and task-oriented competition, which respectively focus on surpassing peers for status and on personal growth. This thesis introduces new scales tailored for assessing academic competition among adolescents. A pilot study involving 532 adolescents in southwestern Ontario (Mage =15.23) validates these scales through factor analysis using Principal Component Analysis, distinguishing between other-referenced and task-oriented competition. The new scales demonstrate reliability, with Cronbach's alpha coefficients of .789 for other-referenced competitiveness and .825 for task-oriented competitiveness. Regression analyses reveal a significant positive association between other-referenced competitiveness and bullying perpetration, while task-oriented competitiveness shows a moderate inverse relationship with bullying. These findings underscore the need to differentiate between competition for skill development and for status, as the latter may inadvertently foster bullying tendencies. This study emphasizes the importance of nuanced understanding in academic competition and its implications for student well-being. The discussion encompasses implications, limitations, and avenues for future research in this area
Aspects of bioorganic chemistry - a). Development of caffeine-aptamer for coffee decaffeination; b). Study of 1,8-naphthalimide derivatives as fluorescent probes; c). Encapsulation of DNA by silica nanoparticles
Get PDFResearch described in this thesis encompass three aspects of bioorganic chemistry:
Caffeine- binding aptamers were sought to remove caffeine from coffee brew. Toward this goal, theophylline carboxylic acid and caffeine carboxylic acid were synthesized, and immobilized to ω-aminohexyl–agarose. The immobilized compounds were used for aptamer selection. The ionic composition of medium roast coffee grinds was determined by ICP-MS. In addition, the amounts of caffeine and theophylline in these brews were also determined by UV/vis and HPLC. The work described in this thesis provided the foundation for future aptamer selection.
The development of 1,8-naphthalimide derivatives was motivated by an ability to stain biomolecules based on differences in their hydrophobicity. 1,8-naphthalimide derivatives were synthesized, and their photophysical and staining properties were investigated. The fluorescence intensity of 4-phenyl-1,8-naphthalimide was found to be very sensitive to solvent polarity, where the compound is virtually non-fluorescent in DMSO, large folds of fluorescence turn-on were seen in less polar solvents. Furthermore, this compound showed aggregation-induced emission characteristics. 4-Aryl-N-ethoxyethyl- and N-[2-(2-hydroxyethyoxy)ethoxy]ethyl-4-aryl-1,8-naphthalimide derivatives were also synthesized, with various aryl substituents (methoxy, amine, dimethyl amine, acetanilide). These compounds were found to be highly fluorescent in chloroform but were drastically reduced in DMSO and methanol. These dyes were found to be suitable probes for protein hydrophobicity, with up to 80 fold fluorescence turn on in the presence of BSA, but virtually no change in myoglobin.
The thesis also explored the encapsulation of DNA by SNPs as an approach to protect DNA. Toward this goal, commercial SNPs were functionalized by the treatment with TMAPS and TEOS introducing a surface positive charge. Upon deposition of DNA to the positively charged surfaces, encapsulation was carried out by treatment with TMAPS and TEOS in the presence of ammonium hydroxide. This encapsulation protocol was first demonstrated using Reactive Green-19. In addition, DNA was readily encapsulated and released by the treatment with ammonium hydroxide at 60°C for six hours, and amplified by polymerase chain reaction and detected by gel electrophoresis. The SNP-encapsulated DNA was found to pass through beds of sand and could therefore be used in environmental tracking in sandy conditions
The Acculturation Experiences of Newcomer Healthcare Workers in Rural Canada: A Case Study
Get PDFThe acculturation experiences of newcomer healthcare workers in rural Canada are complex and influenced by individual, community, and systemic factors. My study explored how these workers navigated acculturation within rural Canadian communities and workplaces, using Berry's model of acculturation as a framework. I examined the strategies of integration, assimilation, separation, and marginalization, shaped by the rural context.
I employed a qualitative case study methodology, focusing on a specific rural municipality in Canada. Data were collected through semi-structured interviews with newcomer healthcare workers, community members, and coworkers from a healthcare facility. Reflexive thematic analysis facilitated an in-depth exploration of participants' lived experiences, and the identification of key themes related to their acculturation process.
My findings revealed that the rural context presented unique challenges and opportunities. Challenges included navigating infrastructural barriers like inadequate transportation and housing, coping with work-related stress, and managing cultural differences in the workplace. Conversely, strong community support systems and inclusive workplace policies positively impacted adaptation. I highlighted the importance of community engagement, social interaction, and the visible contributions of newcomers in fostering a sense of belonging.
Moreover, my research emphasized the dual nature of acculturation, where both newcomers and host communities engaged in mutual adaptation. Community-driven initiatives, informal social networks, and supportive relationships with colleagues were crucial in helping newcomers feel welcomed and valued. However, areas for improvement were identified, such as enhancing rural infrastructure and providing targeted support to address acculturative stress.
My study contributes to the academic discourse on acculturation by providing evidence on the experiences of newcomer healthcare workers in rural settings. It highlights the need for policies fostering inclusive environments to enhance their well-being. The insights gained can inform the development of responsive support systems, programs, and policies aimed at improving the retention and integration of newcomer healthcare workers in rural Canadian communities.
By addressing specific challenges and leveraging identified strengths, rural communities can better support the acculturation process and benefit from the valuable contributions of newcomer healthcare workers
Investigating cross-education in multiple sclerosis following upper limb robotic rehabilitation
Get PDFThe overall goal of this thesis was to develop an adaptive rehabilitation technique using a haptic wrist robotic device that would induce the phenomenon of cross-education to improve upper limb function. Following a literature review, Chapter 4 provides a scoping review of existing literature surrounding rehabilitation robots for MS. Chapter 5 reports the development and rationale of the rehabilitative approach, to develop an algorithm that is individualized and adaptive to the user. Once the algorithm was developed, an eight-week intervention for fourteen individuals with MS and eight non-affected adults was conducted. The purpose of the intervention was two-fold and presented in Chapter 6, to improve overall wrist and grip strength (assessed via maximal grip and isometric wrist strength) and Chapter 7, to improve overall motor control (assessed via robotic performance measures). Lastly, in both chapters, cross-over effects of strength and motor control to the untrained limb were evaluated. Results of this eight-week training reported increases in wrist strength for the MS group with an average percent change score across all muscle directions of 62.59% in the trained limb and 53.26% in the untrained limb. The control group also reported an average percent change of 31.31% in strength in the trained limb and 24.26% in the untrained limb. MS participants significantly decreased in tracking and figural error (degree of error) post-intervention suggesting evidence that motor control adaptations are possible following an adaptive and resistive robotic intervention of the upper limb. Following the results of the eight-week intervention, Chapter 9 was to investigate changes in strength and motor control following four-weeks of training in an additional subgroup of participants following the same rehabilitative protocol. Results demonstrate a clinically meaningful improvement in strength of the trained limb, but no significant improvements in figural or tracking error performance – suggestive that robotic rehabilitation of this kind needs to be longer in duration than four-weeks to elicit meaningful adaptations of motor control
Environmental and social influences of foraging behaviour and maternal investment with a note on the mating frequency of the eastern carpenter bee, Xylocopa virginica
Get PDFThis thesis studies how weather and sociality influence the foraging effort input costs of brood production, and that multiple mating contributes to low-group relatedness and non-kin sociality in the Eastern carpenter bee, Xylocopa virginica. In Chapter 2, using a natural experiment which included a drought and three normal weather years, we found that mothers foraged more in a drought but had smaller offspring than most normal weather years. Droughts conditions lead to fewer flowers, and it follows that less abundant food resources should lead to a trade-off of more work for fewer resources. Indeed, we found that during the drought, the size of pollen loads that mothers carried were smaller than in every other normal year showcasing the impact of the drought. In Chapter 3, I assess the foraging effort in both solitary and social foundresses showing that the foraging input costs are much higher for social primary foundresses than for solitary foundresses. That foraging costs are higher for social foundresses is atypical compared to most literature, which usually suggests that solitary behaviour is more costly than social behaviour. Lower social costs implies that social behaviour should become the more predominant phenotype in the population, however, in our Niagara population there was always a mix of solitary and social phenotypes. A mix of solitary and social phenotypes suggests balanced selection for both phenotypes. That the social phenotype is more costly is interesting and we suggest that social primary foundresses must feed their nestmates throughout the foraging period. Nestmate feeding has been documented in this bee before, so it seems like the most plausible explanation. In Chapter 4, we assessed the mating frequency of female carpenter bees using behavioural observations and microsatellite markers. We found using both sets of data that X. virginica mates multiply. Multiple mating has direct implications on the genetic relatedness of already low relatedness in non-kin social groups. Non-kin sociality is understudied, and we hope that these findings spur additional studies
Edge Communication Efficiency with GNN in the Internet of Vehicles
Get PDFVehicular edge plays a central role in ensuring an effective allocation of resources to provide services and applications. Resource allocation and communication in dynamic vehicular environments face numerous challenges in efficiently managing resources and data sharing, specifically managing the intricate balance of connectivity, storage, energy, computing, and cost of resources. These challenges are also affected by mobility, resulting in the demand for precision in communication range, density, and resource availability. Efficient resource allocation is a critical objective within vehicular networks, and to achieve this, intelligence, prediction, optimization, and incentive modelling are often employed. However, challenges persist, such as sporadic connectivity, transmission delays, and the inherent uncertainty of highly dynamic environments. In response to these challenges, this paper introduces the use of graph neural networks (GNNs) to learn hidden spatial and functional patterns in complex vehicular networks. Combining with clustering-based methodologies. This approach enables the intelligent organization of network nodes, reducing transmission delays and enhancing connectivity in dynamic environments. The resulting framework supports predictions and estimates based on evolving communication and mobility patterns. They are further improving the efficiency of connectivity and communications in vehicular edge networks. Using graph neural networks (GNN) and clustering techniques to address connectivity challenges, reduce transmission latency, and manage the inherent unpredictability of rapidly changing vehicular settings, this study is poised to enhance the delivery of services and applications in vehicular networks. It also lays the foundation for prospective research into resource management
Dissecting the role of MAP3Ks TAK1 and ASK1 in IgE-FcERI mediated mast cell exocytosis
Get PDFMast cells are sentinel immune cells and the main drivers of allergic inflammation. Upon allergen exposure mast cells initiate immediate degranulation in the early-phase of the response, followed by de novo production and secretion of pro-inflammatory mediators in the late-phase. Co-stimulating with allergen and SCF results in the amplification of the pro-inflammatory response launched by allergically-activated mast cells, and a connection between the two signalling pathways is the mitogen activated protein kinase (MAPK) pathway. Therefore, this dissertation includes 3 studies that focussed on MAP3K proteins, TAK1 and ASK1, that are potential nexus points in the signaling mechanisms of the allergic inflammatory response. Our previous work identified TAK1 as a central regulator in co-stimulated mast cells, and study 1 found that TAK1 regulates signaling through both the FcERI and ckit receptor individually as well as supporting that the MAP3K level is an appropriate target for therapeutic development of mast cell stabilizers. Study 2 was carried out to determine if other MAP3Ks, specifically ASK1 also exhibited the regulation observed with TAK1 in allergically-activated mast cells. We found that despite ASK1 sharing the same level in the MAPK cascade, its inhibition did not have as significant an impact in activated mast cells, suggesting that TAK1 is unique in its ability to regulate mast cell function following allergic stimulation. Study 3 was an explorative study to determine how TAK1 is able to exert its regulatory effect on the allergic inflammatory response. We identified a novel interaction between TAK1 and the lipid kinase PIP4K2B. This discovery elucidates the mechanistic placement of TAK1 in mast cells and increases our understanding of the regulation of mast cell inflammatory mechanisms. Taken together, the following research shows that different MAP3Ks exert varying levels of regulatory control in allergically activated mast cells, with TAK1 appearing to be robustly influential, especially compared to ASK1 under the same conditions. Furthermore, we present evidence to support a novel interaction between TAK1 and mechanisms supporting the generation of PIP2, which has the potential to lay the foundation for a new field of study looking into the relationship between the canonical MAPK pathway and lipid metabolism in mast cells