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GIS based accumulation model of microplastics loading in the Saint John River watershed
Get PDFAs microplastic pollution in freshwaters becomes a greater area of focus for many researchers, the development of GIS based mapping tools specific to this field becomes increasingly important. Although many GIS models have been constructed to map the transport and sedimentation of various types of particulates through river systems, models specific to microplastics have yet to be developed. The goal of this study was to create a GIS based accumulation model of microplastics loading in the Saint John River
watershed. This model considers the location of potential microplastic point sources such as wastewater treatment plants and tributaries, as well as the rivers flow strength and direction. Observed suspected microplastic concentrations from the Kennebecasis and Naskwaak tributaries were used to calibrate and test the accuracy of the model’s predictions. Waste water treatment plants seem to be better predictors of suspected microplastic concentrations than tributary confluences. The outcome of this project will further the understanding of microplastics pollution in the Saint John River watershed, and will serve as a reference to implement similar models in other freshwater systems
"Pull your heart to my heart": Touching the past to build queer selves, communities, and theologies for the present
Get PDFRooted in my own experience as a queer cradle Anglican, this thesis seeks to address theological obstacles to contemporary queer Christian identity that alienate queer Christians from God and overlook the theological value of queer forms of knowledge. It investigates potential resources for the expression of queer Christian identities and queer relationships with God, through the possibility of forming affective relationships with past figures who can be identified as queer. Building on the work of queer historian Carolyn Dinshaw, the thesis finds such a resource in Margery Kempe of Lynn, a fourteenth-century Christian mystic who negotiated the margins of medieval domestic and religious life
Meaning-making and resilience in parents of children with complex care needs
Get PDFThis study explored: (1) the ways and extent to which parents of children with complex
care needs (CCCN) find and create meaning in their caregiving experiences; and (2)
parents’ perceptions of the relationship between resilience and meaning-making. The
sample included seven parents who were recruited through online support groups,
NaviCare/SoinsNavi (NB patient navigation centre’s family advisory council, and word of mouth. They participated in semi-structured qualitative phone interviews, which were eventually analyzed using thematic analysis (Braun & Clarke, 2012). Overall, this study found that parents of CCCN made several meanings of their caregiving experiences, including but not limited to acceptance, growth, resilience, and finding purpose. As a conclusion of this study, the findings suggest that meaning-making in parents of CCCN likely follows an iterative and ongoing process. Furthermore, perceived parental meaning-making seems to be instrumental in their ability to cope with caregiving’s difficulties
The effects of decreased intracellular -taurine concentration on cardiac function in brook trout (Salvelinus fontinalis)
Get PDFTaurine (2-aminoethanesulfonic acid) is amino acid found in high concentrations in vertebrate muscle tissues. In teleosts it has been shown to be an important molecule involved in cardioprotection, osmoregulation and modulation of intracellular Ca2+. Previous studies have shown that taurine deficiency is associated with cardiomyopathy and disruptions in energy metabolism. In this study the effects of taurine deficiency on cardiac function in brook trout, Salvelinus fontinalis, was assessed in vivo using intraarterial pressure measurements and metabolite assays. We hypothesized that by feeding brook trout a diet containing β-alanine, a competitive inhibitor of taurine transporter (TauT), that differences in heart function would be discovered when compared to fish fed a control diet. The study incorporated two treatment groups, a group of brook trout fed pellets vacuum coated in β-alanine to decrease intracellular taurine concentrations and a group of brook trout fed a standard diet. This study found that brook trout who had been fed the taurine depleting β-alanine diet had similar blood pressure, heart rate and chase-to-exhaustion times as brook trout fed standard diets. A significant decrease (p=0.023) in pulse pressure was observed in brook trout fed the taurine depleting β-alanine diet. The findings of this study show that taurine deficient brook trout have altered cardiac function in comparison with brook trout fed standard diets. These findings are important understanding the physiological role of taurine in vertebrate hearts
L-Phenylalanine activates class A orphan G protein-coupled receptors
Get PDFG protein-coupled receptors (GPCRs) are the largest family of cell membrane proteins in the human genome. They account for the majority of pharmacological targets due to their physiological diversity and implication in diseases. Despite many efforts to identify the ligands of GPCRs, there are many with no known endogenous ligand, deemed orphans. GPCRs are known to bind a wide variety of ligands, including L-amino acids. This study aimed to investigate the amino acid activation of 72 orphan receptors using a high-throughput screening (HTS) method. The signaling of six orphan receptors was significantly modulated following treatments with a 4/8X mixture of essential/non-essential amino acids: GPR12, GPR26, GPR37L1, GPR84, GPR88, and MRGPRX2. All receptors were activated by the 4/8X mixture except GPR37L1, which, following treatments with individual amino acids, its decrease in signaling was attributed to L-Arg with a fold change of 0.70. The remaining receptors were all significantly activated by L-Phe. In the case of GPR12, GPR84, and GPR88, activation by L-Phe surpassed that of the 4/8X amino
acid mixture with fold changes of 2.66, 2.56, and 5.35, respectively, suggesting possible competitive inhibition during the 4/8X treatment. These results suggest that, through activation of GPCRs, L-Phe may play a much more significant role in metabolic processes than once thought. Determination of the biological relevance of this signaling may one day present a great therapeutic potential for future drug discovery
Investigating amino acid activation of G protein couple receptors involved in lipid metabolism
Get PDFEnergy homeostasis is a dynamic and complex process that maintains a balance between energy intake and expenditure. G protein coupled receptors (GPCRs), the largest family of transmembrane receptors, are critical for the cellular communication needed to coordinate processes involved in energy homeostasis (e.g. food intake). Indeed, metabolites are thought to act as sensors of energy stores by activating GPCRs in order to regulate energy homeostasis. Amino acids in particular have been shown to activate a growing number of GPCRs such as the calcium receptor (CaR), the orphan GPCRs GPR142 and GPR139, the purinergic receptor P2Y, and the hydroxycarboxylic acid receptor HCA3. This study aimed to further elucidate the role of monomeric amino acids as signaling molecules by employing a high throughput screen approach in which 19 monomeric amino acids were screened against 72 lipid metabolism GPCRs in a human cell line. Receptor activity was measured using the G-protein independent -arrestin recruitment PRESTO TANGO assay. It was found that a mixture of 19 essential and non-essential amino acids significantly activated 14 lipid metabolism GPCRs. Of these, MC4, DP2, GPBA, S1P1, and S1P4 were chosen for further investigation and were found to be significantly activated by 0.8 mM L-Phenylalanine. This finding suggests L-Phenylalanine may play a more prominent role as a signalling molecule at GPCRs regulating energy homeostasis than previously thought. This aids in elucidating the satiating mechanisms of high protein diets and has important implications for research into diseases such as obesity, type 2 diabetes, and the metabolic syndrome
Dimethylsulfoniopropionate content in Ulva under salinity stress and immunotitration of an Ulva mutabilis methylthiohydroxybutyrate S-methyltransferase
Get PDFGovernment contingent liabilities: Hidden debt and fiscal risk
Get PDFAs ideas of economic management have developed, governments around the globe have taken an increasingly large role in their domestic economies. Leaders have faced increasing pressure to simultaneously decrease annual deficits, offer more services, and maintain economic growth. As a result, many leaders have intentionally and unintentionally turned to contingent liabilities. Contingent liabilities, often unrecorded or recorded insufficiently on the balance sheet, allow the offering of services or subsidies through the creation of off-balance sheet obligations – effectively allowing a governing party to provide more to citizens without having to deal with the political consequences of deficits or a growing national debt. As the topic of contingent liabilities has become an area of focus for scholars, it has become clear that while contingent liabilities do not cause fiscal crises, their propensity to occur at the same time create a more fragile fiscal state than traditional debt indicators such as gross debt show. This literature review compiles and represents the major sources within the field showing the causes, impacts, and solutions for government contingent liabilities
Rhodium catalyzed alkynoic acid cyclizations
Get PDFThe synthesis and characterization of a novel indenylrhodium(I) complex has been investigated. The reaction of two equivalents 1,3,5-triaza-7-phosphaadamantane added to one equivalent di(cyclooctene)indenylrhodium(I) dissolved in THF resulted in a 67% yield of indenylbis(1,3,5-triaza-7-phosphaadamantane)rhodium(I). The catalytic activity of the complex was assessed using the intramolecular alkynoic acid cyclizations of 4-pentynoic acid and 5hexynoic acid. Addition of 5 mol% of the catalyst resulted in complete conversion from 4pentynoic acid to γ-methylene-γ-butyrolactone at room temperature in only 24 hours. Furthermore, 2 mol% of the catalyst facilitated the complete conversion of 4-pentynoic acid in under 2 hours with moderate heating. The addition of 5 mol% of the catalyst to a solution of 5-hexynoic acid resulted in a partial conversion to 6-methylidenetetrahydo-2-pyrone after 6 hours with heating
