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A surface plasmon resonance investigation of the role of bilayer phospholipids in the binding and ligand interactions of the ⍺-tocopherol transfer protein.
Get PDFVitamins are, by definition, required for maintaining the health of the mammalian body. Vitamin E, which occurs in eight different forms, has a crucial function as an antioxidant protecting polyunsaturated fatty acids. Attributable to the occurrence of alpha-tocopherol transfer protein (a-TTP), RRR-a-tocopherol is the only form that is selectively retained in mammals. a-TTP aids in secreting the RRR-a-tocopherol from liver to the rest of the body. The mechanism of the a-TTP-mediated movement of a-tocopherol is not yet fully elucidated. The opening of a-TTP's binding pocket and subsequent release of a-tocopherol are made possible by a-TTP's interaction with PM residing phosphatidylinositols. K217, a crucial amino acid, is present in the positive surface patch of a-TTP, which is essential for orchestrating this interaction. Surface Plasmon Resonance (SPR) was employed in this study to examine the absorption and desorption of wild-type a-TTP and the mutated form K217A to tethered phospholipid vesicles. SPR spectroscopy illustrated the affinity of either protein when it was presented with one or both of its preferred ligands (a-tocopherol or phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2]) on tethered vesicles. Bovine serum albumin (BSA) was used to coat the side of the microcentrifuge tubes to mitigate protein loss that was discovered when protein was preincubated with its ligands. K217 was found to be instrumental in the binding of TTP to PIPs and the subsequent release of tocopherol. As K217A mutant had a lower adsorption to membranes containing PI(4,5)P2 vs wtTTP. It was determined that α-TTP binding to endosomal vesicles increased with increased concentration of the late endosome specific lipid bis(monoacylglycero)phosphate (BMP). Collections runs performed provided some evidence for the exchange of ligands when wtTTP was used but not for K217A. The results found in this work parallel literature findings and supplement the proposed mechanism of a α-TTP-mediated movement of α-tocopherol and PI(4,5)P2 in plasma membranes
Surgite Volume 15 No. 1, Winter 2023
No full textPublication of Surgite for Volume 15, Number 1, Winter 2023. The contents are: Success a Community Effort, Tips for Self-Kindness and Why it Matters, Education Unlocks President's Potential, Nursing Grads Take on Tough Roles, Equipment Helping Research to Shine, Shaping Future Canada Games, Brock's Runners Through Time, Where are they Now?, Remembering Ned Goodman
Medieval Charter, 1281
Get PDFA late 13th century Latin medieval charter from Spain, handwritten on parchment in the year 1281, from the reign of Alfonso X of Castile. There is a charming signum at the end of the manuscript. This charter has been written in a 15 line format
Understanding the Relationship between Online Discussions and Bitcoin Return and Volume: Topic Modeling and Sentiment Analysis
Get PDFThis thesis examines Bitcoin related discussions on Bitcointalk.com over the 2013-2022 period. Using Latent Dirichlet Allocation (LDA) topic modeling algorithm, we discover eight distinct topics: Mining, Regulation, Investment/trading, Public perception, Bitcoin’s nature, Wallet, Payment, and Other. Importantly, we find differences in relations between different topics’ sentiment, disagreement (proxy for uncertainty) and hype (proxy for attention) on one hand and Bitcoin return and trading volume on the other hand. Specifically, among all topics, only the sentiment and disagreement of Investment/trading topic have significant contemporaneous relation with Bitcoin return. In addition, sentiment and disagreement of several topics, such as Mining and Wallet, show significant relationships with Bitcoin return only on the tails of the return distribution (bullish and bearish markets). In contrast, sentiment, disagreement, and hype of each topic show significant relation with Bitcoin volume across the entire distribution. In addition, whereas hype has a positive relation with trading volume in a low-volume market, this relation becomes negative in a high-volume market
Program Evaluation of a Specialized Treatment Home for Adults with Severe Challenging Behaviour
Get PDFIndividuals with intellectual and developmental disabilities who engage in severe challenging behaviour comprise 5-10% of the population and experience significant limitations in meaningfully participating in everyday activities due to associated risks (e.g., substantial injury to self and others, extreme property destruction, outward physical aggression targeting others). Unfortunately, research featuring adult participants who engage in severe challenging behaviour is relatively scare compared to child participants. Further, challenging behaviour literature tends to emphasize efficacy (e.g., Does the intervention work?) more often than effectiveness (e.g., Does the intervention work in real world settings?). The current project thus was a systematic program evaluation conducted to evaluate the effectiveness of a comprehensive behavioural treatment package at reducing severe challenging behaviour and generating adaptive skills in adults with intellectual and developmental disabilities. A hybrid nonexperimental consecutive case series design was employed featuring all participants (n = 8) who experienced the treatment package, regardless of their success. The results depicted primarily therapeutic outcomes with a substantial decrease in challenging behaviour from baseline to intervention for majority of participants (n = 5) and an increase in adaptive behaviour (i.e., number of mastered skills targets) for participants (n = 7) across the intervention condition. Treatment fidelity suggests frontline staff were largely implementing the interventions as intended (M = 84%, range 82-90%). Social validity surveys administered to participants, caregivers, and case managers provide support for the acceptability of treatment goals, procedures, and effects. Project limitations, clinical considerations, and future directions are discussed
Epidemiology, genetic variance, and symptomology of grapevine viruses in Canada: A metagenomic approach
Get PDFThe global grape and wine industry holds plays a significant role in the Canadian economy. However, the spread of grapevine viruses is posing a serious threat to this industry. Two such viruses, Grapevine Pinot gris virus (GPGV) and Grapevine Red Blotch Virus (GRBV), have caused substantial harm in viticulture regions like Italy and the United States, and their presence in Canada has recently been confirmed. Despite this, many epidemiological aspects of these viruses in Canada remain poorly studied. This two-part project seeks to provide novel insights into the epidemiology of GPGV and GRBV.
The first part focused on investigating the genomic variance of GPGV in Canada. Researchers obtained the genome of 26 GPGV isolates from the four main grape-growing regions of Canada through high throughput sequencing. Phylogenetic analysis of their genomes revealed that Canadian GPGV is closely related to GPGV isolates in the United States, but distinct from isolates in Europe and Asia. The source of GPGV in Canada was likely a recent import from France, and the majority of Canadian GPGV isolates belong to the asymptomatic clade.
The second objective involved monitoring the spread of grapevine viruses by deploying 40 virus-free sentinel vines in two vineyards of different agronomic practices in the Niagara region, both heavily infected with GRBV and GPGV. After 4 months of exposure to the infected vineyards and 11 months in a controlled environment, 46% of surviving sentinel vines were infected with GPGV. No spread of GRBV was observed. GPGV spread faster in the organic vineyard (72% infection rate) compared to the conventional one (5% infection rate). A scan for alternative hosts for grapevine viruses found that all samples from floor covering and perennial plants were free of grapevine viruses, but four out of five wild grape samples harbored GPGV.
These findings underscore the importance of rigorous screening of imported plant material to prevent the introduction of grapevine viruses to Canadian vineyards. To safeguard the sustainability and profitability of Canada's grape and wine industry, a reliable local source of virus-free planting material is imperative. Furthermore, vineyard managers should remain vigilant regarding wild grape, which can act as alternative reservoirs for grapevine viruses
The September He Remembers
No full textThe Summit Series, a best-on-best hockey tournament played between the former-Soviet and Canadian men’s teams, occupies an outsized role in the Canadian sporting imagination.
The September He Remembers: Josef Kompalla and the 1972 Summit Series reframes this famous Series in sport history through the story, experiences, and memories of Josef Kompalla, a German referee who played a key role in the events as one of the few esteemed officials selected to officiate during the Series. Given Kompalla’s important place in the history of the Summit Series, one of the most mythologized and celebrated tournaments in Canadian sport history, it should come as a surprise that his perspective on the events has not been previously documented. In this book, Bolz seeks to rectify this longstanding oversight through intrepid archival creation and analysis, as well as previously-untold stories from Kompalla himself.
Although Kompalla’s role in the Summit Series has been largely omitted or obfuscated for the past half century, The September He Remembers is finally the first step in correcting a major historical oversight and adding a new chapter in the Summit Series’ growing legacy
Synthesis of a Photocleavable Bolalipid for the study of the roles of Phospholipid Transfer Proteins and Phosphatidylinositol Lipid Kinases
Get PDFThis thesis was dedicated to the synthesis of mono- and di-photocleavable phosphatidylcholine bolalipids that were designed to investigate the mechanism of action of the phospholipid transfer protein, Sec14, as well as the phosphatidylinositol 4-kinase, Pik1. While it was the goal of this thesis to synthesize both bola-PCs, only the mono-photocleavable bola-PC was successfully synthesized. The mono-photocleavable bola-PC lipid was designed to contain two glycerol molecules that each had a choline head group connected through a phosphodiester bond at the sn3 position. Each glycerol was acylated with palmitic acid at the sn1 position. These two glycerol moieties were then connected to one another through their respective sn2 hydroxyls via a mono-photocleavable dicarboxylic acid. The initial steps of this work were to synthesize mono- and di-photocleavable diacids to serve as a linker for the polar head groups of the bolalipids. The mono- and di-photocleavable diacids were designed to contain one and two nitrophenyl ethyl photolabile protecting groups, respectively. The synthesis of the di-photocleavable diacid was attempted first, however, these efforts were unsuccessful. Two separate synthetic routes were followed to synthesize this diacid, but neither were viable. Despite this, the synthesis of the mono-photocleavable diacid was successful and was incorporated into a bola-PC. The mono-photocleavable diacid and bola-PC were found to undergo photocleavage when irradiated with 365 nm light, in 60 seconds and 105 seconds, respectively. Photocleavage of the bola-PC was also carried out within a lipid vesicle comprised of 10% bola-PC and 90% DOPC. Spectral and experimental data have been provided for all compounds synthesized. Future efforts will involve the bola-PC synthesized in this thesis undergoing enzymatic conversion into a bola-PI, via the enzyme phospholipase D
Unfamiliar and newly learned face identification: An examination of individual differences
Get PDFFace identification involves two tasks: Recognizing an individual even when their appearance changes, and discriminating them from similar-looking individuals. People vary in the accuracy with which they identify unfamiliar faces. Much of the work investigating individual differences in face identification used tightly controlled stimuli (i.e., focused on discrimination). Few studies have used stimuli that incorporate variability in appearance (e.g., focused on recognition). Despite interest in individual differences, and understanding that recognizing a face across instances poses a difficult challenge, many gaps in the literature remain. These include potential predictors, the reliability and convergent validity of face identification tasks, and whether unfamiliar face identification predicts face learning efficiency.
I examined a potential predictor of face identification—photography experience (Chapter 2). I recruited photography Experts, Hobbyists and Novices to take part in an unfamiliar face identification task. Photography experience was not a significant predictor of sensitivity in unfamiliar face identification. However, it was a predictor of response bias.
I examined the reliability and convergent validity of face identification tasks (Chapter 3). Participants completed four unfamiliar face identification tasks on two days (study 1), or two versions (simultaneous and sequential) of three unfamiliar face identification tasks (study 2). Sensitivity to identity and bias were stable across time and tasks. Response times were fastest on trials that were congruent vs. incongruent with one’s bias, providing preliminary evidence that this reflects decision-making processes.
I examined whether unfamiliar face matching predicts face learning efficiency (Chapter 4). Participants completed two unfamiliar face matching tasks and a novel face learning task (which tested recognition four times during learning). Individual differences in the slope of face learning
were predicted by unfamiliar face matching ability. These differences appear to be driven by individual differences in recollection, not familiarity.
My dissertation provides insights about individual differences in face identification. Individual differences in sensitivity in unfamiliar face identification were stable across time and tasks. They also predict face learning efficiency. My results suggest that face identification is not just a perceptual problem—it is influenced by decision making and other processes. These results have implications for face identification theories and applied settings
Letters by Thomas Elwyn to his brother William, 1805, 1812
Get PDFThomas Langdon Elwyn (c. 1776-1816) was born in Canterbury, England. He graduated from Oxford University in 1794 and emigrated to the United States the following year. Elwyn married Elizabeth Langdon, who was the daughter of John Langdon, a New Hampshire statesman.Three letters written by Thomas Elwyn in Portsmouth, New Hampshire to his brother William in England, 1805-1812. Two of the letters were written in 1812 and mention the War of 1812 between Britain and the United States.
The first letter is dated at Portsmouth [New Hampshire], March 14, 1805, and is addressed to George’s Coffee House, Temple Bar, London. The letter is four pages. Elwyn writes about his work publishing an anonymous pamphlet titled “Letter to a Federalist” defending Thomas Jefferson and his Administration against Federalist critics. Although he did not put his name to it “the feds discovered the author and everything was sought for to abuse me personally”. He writes about the praise and criticism he received since its publication but is very pleased with his work, noting that “the facility with which I write is amazing to myself…my elegance of language, admirable choice of words, and great power of commanding the attention may enrich me very greatly”. Elwyn had sent a copy of this publication to President Jefferson and later received a letter from the President thanking him for his support.
The second letter is dated at Portsmouth, January 25, 1812, and is addressed to W.B. Elwyn, Barrister at Law, Bristol, England. The letter is four pages. Elwyn writes about a possible reunion with his brother in England but notes that “I will never…take my family from this place whilst Mr. Langdon [his father-in-law] lives. They shall at least stay to assuage the pains and enliven the last dull scenes of his life”. He goes on to tell his brother not to emigrate, despite the disappointment that this will cause Elwyn and his family. This is because of the political state of the country. There is “no talk but of war within the walls of Congress. An act already passed for raising 25,000 additional regulars. Another nearly so far embodying 50,000 volunteers. 1,900,000 appropriated for the purchases of munitions of war. The President speaking of nothing but resistance to the hostility of Britain. Yet no one alarmed—not a thought of war in the minds of anyone but Congress”. Elwyn also writes that although he is still a Federalist, he has decided to abandon American public life.
The third letter is dated at Portsmouth, December 10, 1812 and is addressed to W.B. Elwyn, Barrister at Law, Bristol, England. The letter is four pages and mostly discusses the war. He writes that “There are so many difficulties in the way of writing in the present unhappy relations of our two countries, that I shall beg you to do towards me as I shall towards you—write whenever you have an opportunity, always think of me with affection and confidence in my regard and let us flatter ourselves that we all continue in good health and shall one day be recompensed for the painful alienation we suffer”. Elwyn writes that he lives as quietly as possible and his property has not been severely injured by the war. He adds that “England has behaved admirably in most respects since the war began. Prejudice and passion subside every day. As manly a war as you will on the drumbeaters in Canada—no sniveling, pitiful submission, no contempt, but for heaven’s sake, no burnings, no wanton destruction and cruelty. This would unite all parties against you…Recollect we are a free country and the reluctance of a great potion of our people to engage at all in the war. This will account for the ridiculous management of our Canada expeditions.