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Radiogenic Isotopic Data From Cenozoic Volcanic Rocks In The Eureka, Ely And Wells Areas Document Spatially Distinct Archean And Proterozoic Mantle And Crustal Domains Across Northern Nevada, USA
Get PDFContinental arc magmatism caused by the subduction of the Farallon plate underneath the North American Plate occurred through the Cenozoic across Nevada. This study looks at volcanic rocks from three regions, Eureka, Ely and Wells, and uses petrography, major, trace element, and isotope (Sr, Nd, Hf, Pb) geochemistry to determine crustal and mantle sources. Eureka has higher 143Nd/144Nd and lower 87Sr/86Sr isotopic signature, consistent with lavas found in western Nevada that erupted through Proterozoic lithosphere. Volcanic rocks from Ely show a north to south gradient, where 87Sr/86Sr and 143Nd/144Nd isotopic signatures in the south are similar to Eureka lavas, whereas the north plot closer to Wells samples emplaced on Archean lithosphere. Wells samples are distinct with lower 143Nd/144Nd, and lower Pb isotope ratios than other localities. Comparisons with other lavas erupted through the Archean Wyoming Craton show similar isotopic signatures, supporting that Wells lavas are sourced from the Wyoming Craton
The European Honey Bee – A Potential Biomonitor of Tree Fruit Pathogens
Get PDFThis project explores the potential and limitations of using the European honey bee as a biomonitor for pre-screening fungal and bacterial pathogenic threats to beekeeping and the Canadian commercial tree fruit sector. Over 220 samples from tree fruit farms across British Columbia and Ontario were sequenced through the ION torrent platform. Bioinformatics pipelines detected plant and bee pathogens using fungal ITS1 and bacterial 16S rRNA V regions. Pollen and forager bees displayed high sequence detections of Podosphaera leucotricha (Powdery mildew) and Alternaria prunicola (Cherry leaf spot). Sequences from the Monilina genus, including M. ssiori and M. linhartiana, were identified. M. vaccinii corymbosi (mummy berry) sequences were detected in BC blueberry farms. Fungal bee pathogen sequences identified in the samples include Ascophaera apis (Chalkbrood disease) and B. alvei (Pollen mould), and the bacterial pathogen Melissococcus plutonius (European foulbrood disease) was also detected
Design and Implementation of a High-Performance SAR ADC with Non-Standard Capacitor Arrays and Optimized Switching Control Logic
No full textThe results in this thesis show the design of a SAR ADC made in a 130nm PDK with a non-standard capacitor array to have a smaller total layout area and higher ENOB while operating at a sampling rate of 10kS/s. Its design includes adding a clock-boosting circuit to the sample and hold circuit with an ENOB of 14.1, a VCDE to allow for higher sampled voltages to be converted to digital bit streams. The TSMC 130nm PDK was also used to for their standard cell library to create the SAR logic block to minimize the size of its total layout area. Schematic-level simulations of the SAR ADC report an ENOB of 9.5, a best-case DNL and INL of +0.65/-0.65 and +0.97/-0.96, respectively, average power consumption of 1.82μW, and a figure of merit (FOM) of 226.5 fJ/Conv after fixing a power consumption issue in the comparator with calibration schema’s SR latch
The Value of Tiered Chemical Toxicity Testing
No full textMost of the chemicals to which humans are exposed have not been assessed for human health risk. This is largely owed to the time- and cost-prohibitive nature of traditional chemical toxicity tests. Fortunately, there exist simpler alternatives to traditional testing. In a tiered testing scheme— where tests are performed in order of increasing complexity— savings can be realized by not proceeding with more complex tests when simpler tests suffice. Here, we extend to a tiered testing setting a Value of Information framework for weighing trade-offs in the timeliness, cost, and uncertainty reduction of chemical toxicity tests. A “stopping rule” is established and we see that, across 45 hypothetical but realistic scenarios, the expected value of the tiered testing scheme consistently exceeds that of individual tests. As we enter a new era of toxicity testing, VOI-governed tiered testing is a promising avenue for guiding the implementation of time- and cost-effective tests
Identifying Contradictions in Coding and Testing Agile Activities and Exploring Opportunities for Their Resolution: An Activity Theory Analysis
Get PDFThe examination of Coding and Testing activities through the lens of Agile Maturity Models (AMMs) and modern Agile methods remains limited. AMMs identify these activities as foundational capabilities that must be understood before implementing higher-level Agile practices. Using Activity Theory and a sociocultural perspective, 17 contradictions were identified within the two activities. These contradictions were grouped into four themes: Team Structure and Resources, Tools and Technology, Standard Rules and Cultural Norms and Inter-team Dynamics. The contradiction themes enabled the creation of a guide for developing a tool that can be used by Agile practitioners to resolve the contradictions rather than merely acknowledging them. The study's contributions are grounded in AMMs and contemporary Agile methods and can be leveraged to improve processes, foster collaboration, and address inefficiencies in modern Agile teams. The guide enables the development of a practical tool that helps practitioners make targeted improvements in their Agile delivery processes
Real-Time Water Simulation
Get PDFWe present a real-time method for animating and rendering physically-based water for interactive media. We combine a faster gather method for advection and combine this with a semi-staggered grid to avoid the slow atomic operations typically required to make transfer from particle to grid coherent. We show that this provides an increase in performance of approximately 30\% over the conventional atomic-based advection method with marker-and-cell grid. We also present a method for rendering this with a real-time hardware accelerated ray-tracer. The simulation and renderer are coupled so that they make use of the same fluid representation. Using a parallel marching-cubes implementation allows the representation to remain entirely on the GPU. The final performance of the simulation and renderer was found to be higher than the 30fps typically required for interactivity
Application of FactSage to Model the Compositional Variability of the Ni-Cu-PGE Mineralization at the Main Zone of the Tamarack Intrusive Complex
Get PDFThe Tamarack Intrusive complex (TIC) is one of the satellite intrusions of the Duluth Complex, and is located about 75 kilometers west of Duluth, Minnesota. The Ni-Cu-PGE sulfide mineralization at the Main Zone of the TIC exhibits diverse ore types, including disseminated sulfides, semi-massive sulfides, and massive sulfide veins, distinguished by their compositions. This study aims to understand the processes responsible for these variations by employing for the first time the thermodynamic model FactSage 8.3 as a tool to understand the evolutionary path of the sulfide melt. Initial segregation of sulfide liquid was modeled in various ways. FactSage was used to show that the assimilation of 27wt% local semipelite by the presumed parental picritic magma could provoke sulfide saturation. The study also demonstrates that sulfide mineralization at the Main Zone could have been driven by the assimilation of H2S gas generated by devolatilization of the host Virginia Formation durin
The Presumption of Non-Credibility
No full textSexual violence is a rampant issue that affects millions of individuals around the world and especially women. This thesis will explore the work that the presumption of innocence, Section 11(d) of the Canadian Charter of Rights and Freedoms, does in the sexual assault trial in Canada. By discussing the juridogenic nature of Section 11(d) from an anti-carceral feminist perspective, and combined methods approach, I will demonstrate the both essential and vexatious nature of the presumption of innocence. Due-process procedures render a complainant untruthful by the natural effect of rendering an accused person honest, therefore, I argue that Section 11(d) creates and codifies a presumption of non-credibility on complainants. This reflects epistemic injustice and is especially problematic for survivors, because the issue becomes compounded by rape myths and testimonial injustice. The thesis engages in broader arguments around the call for justice beyond judicial convictions and community commitment to change
The Microbiota of Pressure Injuries: Antibiotic Tolerance and Bacterial Dynamics in Polymicrobial Biofilm Infections and Chronic Wound Patients
No full textPolymicrobial biofilms are a frequent cause of infections in pressure injuries. This project developed a polymicrobial biofilm model composed of common pressure injury pathogens Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis, and Stenotrophomonas maltophilia to study the dynamics of pressure injury microbiota. Research indicated that P. aeruginosa inhibits the growth of S. aureus and S. maltophilia, that bacteria were more resistant to antibiotics within mixed biofilms compared to mono and that ciprofloxacin in polymicrobial environments increased CFU/mL of S. maltophilia and S. aureus despite a decreased overall bioburden. Using traditional culture and 16s rDNA amplicon nanopore sequencing, our clinical study indicated high prevalence of Staphylococcus and Corynebacterium, and high abundancies of Bosea species. Whole genome and metagenome sequencing identified resistance genes, aminoglycosides and beta lactams. This research introduced a more clinically relevant biofilm model, highlighted the significance of interspecies interactions, and evaluated the efficiency of current treatments while trialling novel diagnostics
