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Den of heretics: Marsilius of Padua and William of Ockham on Papal Plenitudo Potestatis
Get PDFLong before Louis XIV, the ‘Sun King’ of France (r.1643–1715), ruled absolutely from Versailles, and other monarchs of Enlightened Europe emulated his model of rulership, Catholic
popes, from the pontificate of Innocent III (r.1198–1216), claimed for themselves absolute sovereignty by divine right.1 Theirs was the most — if not the only — effective centralized
monarchy of medieval Europe, having been developed on the basis of an administrative structure inherited from the old Roman Empire.2 In order to sustain the enormous weight of papal
monarchy, popes began, from the twelfth century, to construct a grand theological and legal edifice of their claims to supremacy.3 They were assisted by theologians and canonists who advocated these new papal claims to untrammelled earthly authority, designated ‘papalists’ or ‘hierocrats’ in what follows.4 Unlike Louis XIV, hierocratic popes conceived their authority as extending not just over the people of a single realm, but over all Christians, and even the entire world. Moreover, they considered their supreme authority to encompass not only temporal affairs, directed toward justice, security, and prosperity in this life, but also the spiritual destiny of every Christian seeking eternal life in heaven. Papalists argued that all positive law depends on the pope for its validity, and that secular rulers and inferior churchmen may only exercise authority on papal sufferance. They likened pontifical authority to the sun, without which the heavens and the earth would be left in utter darkness, thus anticipating the sobriquet afforded to Louis. Sweeping papal authority derives, hierocrats asserted, from the status of each pope as vicar of Christ, the all-powerful Son of God — a status that no pope before the twelfth century, each fashioning himself as the vicar of St. Peter, had dared to assert. In short, hierocratic popes claimed to wield fullness of power (plenitudo potestatis) on earth, and presented that claim as holy dogma
The effects of cell size on the C:N:P of phytoplankton
Get PDFPhytoplankton are the primary producers of the global ocean and their elemental stoichiometry (C:N:P) is a central feature of their ecology and biogeochemistry. Understanding the underlying mechanics of phytoplankton C:N:P variation is a key focus of marine biogeochemistry study. We used four diatom species of different sizes, Thalassiosira pseudonana, Thalassiosira weissflogii, Odontella mobiliensis, and Stephanopyxis palmeriana, to investigate how intracellular C:N:P varies with cell volume and determine the biochemical basis of that variation. To do this, we measured the main macromolecular components of C, N, and P in addition to the cellular quotas for these element in all four species during growth at near-optimal, nutrient replete conditions. This study found a negative relationship of C:P and N:P to cell volume that is supported by clear macromolecular mechanisms. This relationship is reflected by larger size-scaling exponents of P relative to C and N. As cell volume increased, species allocated relatively more N and P to residual pools and less to biosynthesis as represented by protein, RNA, and chl a. This study demonstrates that C:N:P variation and P-allocation across a size spectrum reflects a tradeoff between biosynthesis and storage
MIR-744 and MIR-30D act as tumour suppressors in pancreatic ductal adenocarcinoma
Get PDFPancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and has one of the highest mortality rates and poorest prognosis among cancers. Unfortunately, the diagnosis of this cancer is often a lengthy process and requires invasive techniques like tissue biopsies and endoscopies, and the use of various imaging modalities that requires specialized training. The development of liquid biopsy, a non-invasive diagnostic technique that requires a simple blood test, would be beneficial to help diagnose PDAC. My research project aims to identify the biological significance of previously identified up- and downregulated miRNAs found in extracellular vesicles extracted from PDAC patient plasma compared to controls. First, a number of miRNA targets (n = 17) identified by small RNA sequencing in patient samples were validated by droplet digital PCR. Some of these miRNAs (n = 4) were then used to transfect one healthy (H6C7) and one cancerous cell line (PANC 10.05) with a mimic miRNA (increases abundance) and a siRNA (decreases abundance) for each target. The number of live cells was measured 72h post-transfection by flow cytometry. It was found that miR-744-5p mimic decreases the number of live cells (n = 3, P < 0.05), while miR-30d siRNA (n = 3, P < 0.05) increases the number of live cells. Interestingly, miR-744-5p mimic and miR-30d siRNA had no significant effect on the number of H6C7 cells. These results suggest that miR-744-5p and miR-30d may both be tumour suppressor miRNAs in pancreatic cancer
The impact of music streaming platforms and digitally curated content on musicians' career development
Get PDFThe varying concerns streaming platforms have created for artists over the past two decades guided the topic choice for the current study. Streaming platforms have impacted the
way consumers and musicians’ access, share and interact with music (Salo, Lankinen, & Mäntymäki, 2013). The music industry has shifted from a materialized to a dematerialized system since the digitalization of music began with the compact disc (Eiriz & Leite, 2017; Swanson, 2013). As a result, an increasing number of musicians are now responsible for
producing and managing their careers (Eiriz & Leite, 2017). In general, artists have both favourable and unfavourable attitudes towards streaming, depending on several factors or
whether they are fully independent or an established musician (Aly-Tovar, Bacache-Beauvallet, Bourreau & Moreau, 2019; Marshall, 2015). The way artists can connect with their listeners and
recruit new ones has drastically changed with the opportunities the internet has provided, e.g., utilizing different social media platforms and engaging with online communities (Salo et al.,
2013). How the success of an artist is measured has also changed both subjectively and objectively since the digitalization of music (Fisher, Pearson, Goolsby & Onken, 2010). Overall,
there are many components of the music industry that a musician has to be aware of while creating music and developing their career.
The majority of research on streaming platforms has been conducted in the consumer, record label and services sectors; however, little has explored the business models used by early
career musicians in a dematerialized market (Eiriz & Leite, 2017). To address this gap in the research, the current study investigated how early career musicians measure their success in the
2 age of streaming to uncover the challenges musicians face when establishing, expanding and maintaining their music career
Memory representations for visually learned objects and haptically learned objects: Verbally or visually coded?
Get PDFThe encoding specificity principle states that retrieval is most efficient when the retrieval conditions match the conditions when the memory was encoded. However, previous studies have demonstrated a violation of this principle for objects learned by touch, for which identification was equally efficient by sight and by touch. This indicates that sight and touch have a shared memory representation. The present study was concerned with the nature of this shared representation, whether it was primarily visual, verbal, or a combination of both. Seventy-seven participants completed a learning phase where they were asked to learn to recognize eight novel objects haptically or visually. Participants completed the learning phase while being presented with either a verbal, visual, haptic distractor, or no distractor. They then completed an experimental phase where there were presented with an object they could see and one they could touch; they were asked to identify one of the objects and ignore the other. We replicated the violation of encoding specificity, found that visual distractor interfered with haptic identification, and while we hypothesized that a distractor would interfere, none significantly did. This may have been because our interference did not require participants to actively engage with the distractors
Optimizing protocols for the cryopreservation of shortnose sturgeon (Acipenser brevirostrum) germplasm
Get PDFThe effect of chronic hypoxia on ketone body metabolism in brook trout (Salvelinus fontinalis)
Get PDFHypoxic zones are detrimental to fish, and their duration is increasing due to climate change. For short-term hypoxic exposures, teleost fish may rely on anaerobic glucose metabolism via glycolysis, however given the limited glycogen stores in these animals glucose will not be sufficient to survive over the long-term. The substrate that they use to tolerate chronic hypoxic exposures is currently unknown, but amino acids, ketone bodies, or lipids are possible. Ketone bodies may be preferable due to the low oxygen cost, production efficiency, and potential anti-oxidative effects. The purpose of my research was to investigate if teleost fish are capable of metabolizing ketone bodies during exposures to chronic hypoxia. Using brook trout (Salvelinus fontinalis) as our model organism, we placed fish in 50% dissolved oxygen for 24-hours as an acute exposure and 9-days as a chronic exposure, and compared these to control fish and those that were starved for 9 days. After treatment I took blood, heart, liver, and white muscle samples and performed assays to assess ketone activity. Liver glycogen decreased significantly following chronic hypoxia, suggesting that glucose stores were depleted. The activity of β-hydroxybutyrate dehydrogenase was unaffected by exposure to hypoxia and similarly, I observed no changes in plasma β-hydroxybutyrate.
However, plasma acetoacetate decreased significantly following chronic hypoxia, which may be due to increased uptake into tissues. Activity of succinyl-CoA:3-ketoacid-CoA transferase (SCOT) increased in the heart after chronic hypoxia, but SCOT was decreased in white muscle after both acute and chronic hypoxia. This suggests that ketogenic responses are tissue-specific, and that the heart may utilize ketones to maintain a steady ATP source. In conclusion, this research suggests that S. fontinalis is capable of partial ketogenic responses during chronic hypoxia and this may help to support ATP production in obligate organs like the heart
Change in gold nanoparticle surface coatings results in distinct cytotoxic profile across various cancer models
No full textGold nanoparticles (AuNPs) hold unique surface properties, making them interesting candidates for cancer treatments. AuNPs surface chemistry can be modified by binding thiols creating linkage points for different surface coatings. The chemical structure of the coatings regulates the interaction AuNPs have with cells and is an important determining factor in AuNP cytotoxicity. This study looked at AuNP’s functionalized with 4-dimethylaminopyridine (DMAP), and three polyethylene glycol (PEG) coatings: PEG methyl ether thiol (PEGCH3), PEG amine terminated thiol (PEGNH2) and PEG 2-mercaptoethyl ether acetic acid (PEGCOOH). The particles cytotoxic effects were compared across three cell lines: Human embryotic kidney (HEK293T/17), prostate cancer (PC-3) and ovarian cancer (SKOV3)
High-throughput analysis of picocyanobacterial growth responses to a matrix of conditions
Get PDFThe highly dynamic nature of coastal and estuarine ecosystems favours niche specialization of phenotypically and genetically similar strains of picocyanobacteria. Current methods of identification of these strains such as morphological and molecular analysis are either prone to error or contain a lack of representation of the diversity of picocyanobacteria found in coastal and estuarine ecosystems, respectively. Examining how these coastal and estuarine strains of picocyanobacteria respond to ecologically relevant environmental conditions may be an additional method of identification and characterization of these strains. I developed and implemented a high-throughput well plate-based approach for characterizing the growth response of strains of picocyanobacteria to matrices of ecologically relevant phosphate concentrations, nitrate concentrations, and light levels. Using this approach, the three strains I analyzed exhibited distinct growth responses to the matrices of conditions. Thus, I present evidence that this approach can be used for characterization of the niches of picocyanobacteria and may be helpful in terms of identification of these strains, particularly when other methods yield inconclusive results
