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Western E-Vent in Early Modern Philosophy

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Western E-Vent in Early Modern Philosophy

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Western E-Vent in Early Modern Philosophy

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Assessment Of Intrinsic Hand Neuromuscular Physiology, Philemon Tsang

Electronic Thesis and Dissertation Repository

Alterations to the peripheral nervous system and neuromuscular physiology may impact hand function in a typical or clinical population, such as individuals with ulnar neuropathy. The mechanisms that influence these positive and negative changes are still not well understood. The three studies within my thesis aim to validate the reliability of decomposition-based quantitative electromyography (DQEMG) measurements and explore the changes in intrinsic hand neuromuscular physiology in a typical aging population and individuals recovering from a surgical intervention for severe ulnar neuropathy.

The purpose of the first study was to determine the test-retest reliability of near-fibre (NF) jiggle, a measure of ...

Contraction Analysis Of Functional Competitive Lotka-Volterra Systems: Understanding Competition Between Modified Bacteria And Plasmodium Within Mosquitoes., Nickolas Goncharenko

Electronic Thesis and Dissertation Repository

We propose and analyze an extension to the classic Competitive Lotka-Volterra (CLV) model. The goal is to model competition between species, with a response from the environment. This response is a function of the population of all species and can represent numerous physical phenomena including resource limitation and immune response of a host due to infection. We name this new system a Functional Competitive Lotka-Volterra (FCLV) model. We mainly use the construction of contraction metrics, to determine global properties of the model. We use this result to analyze the competition between Plasmodium sp. and genetically engineered bacteria within the midgut ...

Mhcherrypan, A Novel Model To Predict The Binding Affinity Of Pan-Specific Class I Hla-Peptide, Xuezhi Xie

Electronic Thesis and Dissertation Repository

The human leukocyte antigen (HLA) system or complex plays an essential role in regulating the immune system in humans. Accurate prediction of peptide binding with HLA can efficiently help to identify those neoantigens, which potentially make a big difference in immune drug development. HLA is one of the most polymorphic genetic systems in humans, and thousands of HLA allelic versions exist. Due to the high polymorphism of HLA complex, it is still pretty difficult to accurately predict the binding affinity. In this thesis, we presented a new algorithm to combine convolutional neural network and long short-term memory to solve this ...

Advanced Phenotyping Of Otosclerosis In An Ontario Population And Two Large Newfoundland Families, Matthew B. Lucas

Electronic Thesis and Dissertation Repository

Otosclerosis is a relatively common hearing loss disorder characterized by abnormal bone growth in the otic capsule leading to stapes fixation. In approximately half of cases, otosclerosis is inherited as an autosomal dominant trait. Typically, gene discovery efforts rely on surgical confirmation, audiometry and occasionally acoustic reflexes to identify affected cases of otosclerosis within families, requiring that the otosclerosis was at an advanced stage to be detected. This makes it difficult to identify individuals with early otosclerosis. The use of advanced phenotyping to identify cases of otosclerosis was tested in an Ontario otosclerotic population as well as in two large ...

Regulation Of Endoplasmic Reticulum Stress In Saccharomyces Cerevisiae, Sarah R. Chadwick

Electronic Thesis and Dissertation Repository

The budding yeast Saccharomyces cerevisiae has been used extensively to uncover the genetic mechanisms that control basic cellular processes, including survival, maintenance, and response to stressors. One metric of yeast survival is chronological lifespan (CLS), which is the amount of time non-dividing yeast cells can survive at stationary phase. Variations in CLS following genetic alteration are used to understand the function of specific genes and pathways in cellular aging. Many factors contribute to aging, including accumulation of toxic misfolded secretory proteins in the endoplasmic reticulum (ER stress), to which the cell responds through activation of ER stress signaling pathways, such ...

Chemical Communication In Songbirds, Leanne A. Grieves

Electronic Thesis and Dissertation Repository

Avian chemical communication has been understudied due to the misconception that olfaction is unimportant or even lacking in birds. Early work focused on the olfactory foraging capabilities of seabirds because of their ecology (open ocean foraging) and large olfactory bulbs. In contrast, olfaction in passerine birds, comprising over half of all extant avian taxa, was long overlooked due to their relatively small olfactory bulbs. It is now well established that passerines can smell, and their olfactory acuity is comparable to that of macrosmatic mammals such as rats. Much of our theory on communication and mate choice has involved studying visual ...

Oculomotor Task-Switching Performance Improves And Persists Following A Single Bout Of Aerobic Exercise, Diksha Shukla

Electronic Thesis and Dissertation Repository

Executive function includes the core components of response inhibition, working memory, and cognitive flexibility. Interestingly, an accumulating evidence has reported that inhibitory control and working memory improve following a single bout of exercise. It is, however, largely unclear whether cognitive flexibility elicits a similar post-exercise benefit. Accordingly, Chapter Two of my thesis examined whether 20-min of aerobic exercise provides an immediate post-exercise ‘boost’ to cognitive flexibility. Chapter Three examined for how long a putative post-exercise benefit persists. Cognitive flexibility was examined via an AABB task-switching paradigm wherein participants alternated between a well-practiced and a novel oculomotor task pre- and post-exercise ...

Differential Effects Of Freezing On The Drought Tolerance Of Herbaceous Plants At The Species, Community And Ecosystem Scales, Ricky S. Kong

Electronic Thesis and Dissertation Repository

Both freezing and drought cause cellular dehydration and elicit similar physiological responses in plants, where similar protective compounds are upregulated, including soluble sugars and proteins that help reduce cellular damage. Drought-freeze cross acclimation occurs when drought exposure enhances the freezing tolerance of plants. However, few studies had investigated the reciprocal effects of freezing on drought tolerance, and it was unknown if these interactions could impact plant productivity. Therefore, I examined the effects of freezing on the drought tolerance of individual species and assessed the implications of freeze-drought interactions in an old field community. Poa pratensis was exposed to fall or ...

Practical Applications And Future Directions Of Genetic Code Expansion: Validation Of Novel Akt1 Substrates And The Design Of A Synthetic Auxotroph Strain Of B. Subtilis, Mcshane M. Mckenna

Electronic Thesis and Dissertation Repository

In Chapter 1, site-specifically phosphorylated variants of the oncogene Akt1 were made in Escherichia coli using the orthogonal translation system that enable genetic code expansion with phosphoserine. The differentially phosphorylated variants of Akt1 were used to validate newly predicted Akt1 substrates. The predicted target sites of the peptide substrates were synthesized and subjected to in vitro kinase assays to quantify the activity of each Akt1 phosphorylated variant towards the predicted peptide. A previously uncharacterized kinase-substrate interaction between Akt1 and a peptide derived from RAB11 Family Interacting Protein 2 (RAB11FIP2) was validated in vitro. Chapter 2 describes the preliminary development of ...

Effiicient Computation Of Maximal Exact Matches Between Genomic Sequences, Valeria Leticia Portes De Cerqueira Cesar

Electronic Thesis and Dissertation Repository

Sequence alignment is one of the most accomplished methods in the field of bioinformatics, being crucial to determine similarities between sequences, from finding genes to predicting functions. The computation of Maximal Exact Matches (MEM) plays a fundamental part in some algorithms for sequence alignment. MEMs between a reference-query genome are often utilized as seeds in a genome aligner to increase its efficiency. The MEM computation is a time consuming step in the sequence alignment process and increasing the performance of this step increases significantly the whole process of the alignment between the sequences. As of today, there are many programs ...

Expression Changes Confirm Genomic Variants Predicted To Result In Allele-Specific, Alternative Mrna Splicing, Peter Rogan

Biochemistry Publications

Splice isoform structure and abundance can be affected by either noncoding or masquerading coding variants that alter the structure or abundance of transcripts. When these variants are common in the population, these nonconstitutive transcripts are sufficiently frequent so as to resemble naturally occurring, alternative mRNA splicing. Prediction of the effects of such variants has been shown to be accurate using information theory-based methods. Single nucleotide polymorphisms (SNPs) predicted to significantly alter natural and/or cryptic splice site strength were shown to affect gene expression. Splicing changes for known SNP genotypes were confirmed in HapMap lymphoblastoid cell lines with gene expression ...

Phage-Bacteria Interaction And Prophage Sequences In Bacterial Genomes, Amjad Khan

Electronic Thesis and Dissertation Repository

In this investigation, we examined the interaction of phages and bacteria in bacterial biofilm colonies, the evolution of prophages (viral genetic material inserted into the bacterial genome) and their genetic repertoire. To study the synergistic effects of lytic phages and antibiotics on bacterial biofilm colonies, we have developed a mathematical model of ordinary differential equations (ODEs). We have also presented a mathematical model consisting of a partial differential equation (PDEs), to study evolutionary forces acting on prophages. We fitted the PDE model to three publicly available databases and were able to show that induction is the prominent fate of intact ...

Soybean Root Exudates Increase The Physiological Diversity Of Bacteria In Cadmium-Treated Soil, Leily Kazemi Movahed

Electronic Thesis and Dissertation Repository

Three soybean cultivars with contrasting retention of cadmium (Cd) in the root were grown in Cd-spiked nutrient solution and used to determine that symplastic compartmentalization of Cd in roots is probably responsible for retention of Cd in roots. Roots of the low Cd-accumulator AC Hime treated with 30 mM Cd exuded up to 10-fold higher concentrations of citric, succinic, fumaric and malic acids into the hydroponic solution when compared to control; concentrations of the same organic acids from the high Cd-accumulator Westag 97 increased by up to 3-fold. The same cultivars were grown in Cd-spiked soil and the physiological profiles ...

Mushroom Body-Specific Gene Regulation By The Swi/Snf Chromatin Remodeling Complex, Kevin Cj Nixon

Electronic Thesis and Dissertation Repository

Over the lifetime of an organism, neurons must establish, remodel, and maintain precise connections in order to form neural circuits that are required for proper nervous system functioning. Disruptions in these processes can lead to neurodevelopmental disorders such as intellectual disability (ID) and autism spectrum disorder. Mutations in genes encoding subunits of the SWI/SNF chromatin remodeling complex have been implicated in ID, yet the role of this complex in neurons is poorly understood. In this project, I established cell-type specific methods to examine the effect of SWI/SNF subunit knockdowns on gene transcription and chromatin structure in the memory-forming ...

Structural Study Of The Complex Between Dna Polymerase Iota And Ub-Pcna, Harrison Taylor

Electronic Thesis and Dissertation Repository

DNA polymerase iota (polι) is a member of the Y-family, polymerases which are key components in translesion synthesis (TLS). As part of the DNA damage response, TLS allows cells to bypass damaged template DNA. Each member of the Y-family is capable of accurately replicating across from certain lesions. All Y-family polymerases are recruited by ubiquitination of the DNA sliding clamp, PCNA, by direct interaction with PCNA and ubiquitin. The mechanism of polymerase choice is not well understood, nor are the interactions between Ub-PCNA and the TLS polymerases. We studied the structure of the complex between the interacting region of polι ...

Analysis Of The Chemotactic And Anti-Ovarian Response To Honeybee Queen Mandibular Pheromone (Qmp) And Its Constituent Components In Drosophila Melanogaster, Suhayr Solangi

Electronic Thesis and Dissertation Repository

Drosophila melanogaster can mimic qualities of honeybee altruism mediated by queen mandibular pheromone (QMP), a honeybee pheromone, which includes suppression of oogenesis and chemotactic attraction of males to sources of QMP. In this study, I assessed chemotaxis to the components of synthetic QMP (sQMP): the phenols; methyl-p-hydroxybenzoate (HOB) and 4-hydroxy-3-methoxyphenylethanol (HVA), and decenoic acids; 9-hydroxy-decenoic acid (9-HDA) and 9-oxo-decenoic acid (9-ODA). I found that the chemotactic response to these components is sexually dimorphic and they have complex interactions with one another. I conducted a screen to inhibit olfactory receptor neurons (ORN) using tetanus toxin (TeTx) and OrGAL4 drivers. Of the ...

Using An Internal Auditory Stimulus To Activate The Developing Primary Auditory Cortex: A Fetal Fmri Study, Estee Goldberg

Electronic Thesis and Dissertation Repository

Insight into the rapidly developing brain in utero is scarce. Fetal functional magnetic resonance imaging (fMRI) is a technique used to gain awareness into the developmental process. Previous auditory task-based fMRI studies employed an external sound stimulus directly on the maternal abdomen. However, there has since been recommendation to cease doing so. We sought to investigate a reliable paradigm to study the development of fetal brain networks and postulate that by using an internal stimulus, such as the mother singing, it would result in activation of the fetal primary auditory cortex. Volunteers carrying singleton fetuses with a gestational age of ...

Niche Segregation Among Three Sympatric Species Of Swallows In Southern Ontario, Kaelyn H. Bumelis

Electronic Thesis and Dissertation Repository

Barn Swallows (Hirundo rustica), Cliff Swallows (Petrochelidon pyrrhonota) and Tree Swallows (Tachycineta bicolor) breed sympatrically in southern Ontario but it is unclear how these species differ ecologically, and their coexistence implies niche segregation. I investigated potential interspecific differences in nestling diet and post-fledging movements. Using DNA barcoding of nestling feces and stable isotope analysis (δ¹³C, δ¹⁵N, δ²H) of nestling feathers, I found evidence of differences in dietary sources of provisioned young. Barn Swallows showed evidence of provisioning more terrestrial-based prey, Cliff Swallows provisioned an intermediate diet, and Tree Swallows the most aquatic-based diet. To ...

Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell

Electronic Thesis and Dissertation Repository

The fitness of reintroduced salmonids in Lake Ontario can be reduced by high levels of thiaminase in exotic prey consumed at the adult stage. If sensitivity to dietary thiaminase differs among the three Atlantic salmon populations targeted for reintroduction into Lake Ontario, this could significantly influence their performance. I quantified the effects of experimental diets that contained high or low (control) levels of thiaminase on thiamine concentrations, survival, growth rate, and reproductive traits (sperm and egg quality) in Atlantic salmon from the three candidate source populations. Fish that consumed the high-thiaminase diet had comparable growth rates, but lower survival and ...

Biology 4920g: Companion Planting In The Community, Jacquline A. Nathaniel

Community Engaged Learning Final Projects

LIFE*SPIN is a local organization in London, Ontario that provides resources to individuals and families dependent on low income to ultimately break the poverty cycle by encouraging sustainable living and self-sufficiency. For this Seminar in Biology course, Maria Bata and I partnered with LIFE*SPIN to plan and execute a "Seeding Planting Party" to teach children about basic botany, nutrition, and leadership. The following final paper for this seminar discusses the project deliverables and efforts, biological research concerning companion planting, and personal reflection on this experience.

The Role Of Adult Hippocampal Neurogenesis In Depression-Relevant Reward-Related Behaviours, Katrina Zmavc

Electronic Thesis and Dissertation Repository

The variability in the symptomatology of depressive disorders and antidepressant treatment response has led to an increased interest in the molecular, cellular, and circuit mechanisms of many aspects of affect. Evidence suggests a reduction in adult hippocampal neurogenesis (AHN) is associated with an increase in depression-like behaviour, though much of this evidence has been from studies using aversive tests (e.g., forced swim test). Here, I used touchscreen operant chambers, which allow for non-aversive and translational testing, to test the hypothesis that AHN plays a contributing role in emotion regulation. A panel of three touchscreen tests were chosen to assess ...

Arthropod Diversity In Contrasting Ontario Peatlands, Grace Carscallen

Electronic Thesis and Dissertation Repository

Peatlands are important wetland systems, but dominant macroarthropod groups endemic to peatlands and the environmental factors that affect them are poorly represented in the literature. I examined the richness, abundance, and community composition of soil and surface dwelling macroarthropods using emergence traps, peat sorting, and pitfall traps in two Ontario fens differing in water table, nutrient level, and vegetation. I found 218 arthropod morphospecies, with each site having a similar richness of emergent arthropods, but patterns of community composition differed between the two sites. The Carex (sedge) dominated site had twice as many emergent individuals, and total abundances declined dramatically ...

Narratives Of Canadian Identity At The Ultimate Fighting Championship, Jared V. Walters

Electronic Thesis and Dissertation Repository

The purpose of this dissertation was to examine the use of representations and symbols of Canadian identity within the event coverage produced by the Ultimate Fighting Championship Corporation, in the context of its two key events, Ultimate Fighting Championship, and Fight Night, produced in Canada. To establish the historical context in which the sport developed in Canada, a narrative historiography of the political and legal struggles that led to the legalization and increasing popularity of Mixed Martial Arts, and the UFCC’s version of the sport, in particular. This first major part of the dissertation is contained in Study 1 ...

The Difference In A1c Of Children And Adolescents With Type 1 Diabetes Mellitus Using Carbohydrate Counting Compared To Those Using A Structured Meal Plan, Alia El Kubbe

Electronic Thesis and Dissertation Repository

Carbohydrate counting (CHO) is a nutrition education tool used by patients with type 1 diabetes mellitus (T1DM). The primary objective was to assess glycated hemoglobin (A1C) in participants with T1DM using CHO counting vs. those using a structured meal plan (SMP). The secondary objectives were to determine if BMI-for-age, parental income, parental involvement, and mothers’ educational level were associated with their children’s glycemic control. A cross sectional study was conducted, where participants aged 4-18 years, or their parents completed a survey. Total sample size was 88 participants (77 in the CHO counting group and 11 in the SMP group ...

Recovery Following Proximal Humerus Fracture, Azar Varahrami Vigeh

Electronic Thesis and Dissertation Repository

There is currently a glaring gap in the existing knowledge to address individuals’ experiences while recovering from a proximal humeral fracture (PHF). The main objective of this dissertation was to understand better how recovery is perceived by individuals after PHF. This overarching objective aligned well with the broad conceptualization of the issue at hand as those provided by the International Classification of Functioning, Disability and Health (ICF). Three inter-linked studies were conducted to provide a broader picture of recovery after PHF. The first study was a systematic review of prognostic factors predicting recovery after PHF in adults. This review demonstrated ...

The Role Of Connexin And Pannexin Large-Pore Channels In Hearing, Julia Abitbol

Electronic Thesis and Dissertation Repository

Connexin and pannexin large-pore channels allow the regulated passage of small molecules at sites of cell-cell contacts, and from the cytosol to the extracellular milieu, respectively. Since it has been known for many years that Cx26 and Cx30 gap junction proteins are crucial in hearing we propose that Cx43 might also be important in hearing. Here we used two different genetically modified mouse lines that contain systemic Cx43 gene mutations that reduces gap junctional intercellular communication (GJIC) to examine whether Cx43 is also important for proper hearing function. Furthermore, since pannexins have also been postulated to be involved in auditory ...

Executive Dysfunction Following A Sport-Related Concussion Is Independent Of Task-Based Symptom Burden, Naila Ayala Angumba

Electronic Thesis and Dissertation Repository

The present work examined whether oculomotor deficits associated with a sport-related concussion (SRC) reflect an impairment to executive-based planning mechanisms or a task-based increase in concussion symptomology (e.g., headache, vertigo). Therefore, I employed a standardized measure of SRC symptom severity (SCAT-5), antisaccade performance and pupillometry metrics in persons with a SRC during early (i.e., initial assessment: ≤12 days post-SRC) and later (i.e., follow-up assessment: 14-30 days post-SRC) stages of recovery. In the initial assessment, the SRC group yielded longer reaction times (RT) (p=0.001), increased directional errors (p=0.002) and larger task-evoked pupil dilations (TEPD ...