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Petrogenesis of mineralized horizons in the Offset and Creek zones, Lac des Iles Complex, N. Ontario
Get PDFThe Lac des Iles Complex is a Neoarchean polyphase mafic-ultramafic complex located in
the Marmion terrane of the Superior Province, 85 km north of Thunder Bay, Ontario, Canada.
The intrusive complex can be subdivided into two discrete subcomplexes: the ultramafic-
dominated North Lac des Iles Complex and the mafic-dominated South Lac des Iles Complex
(SLDIC). The SLDIC has been subdivided into the gabbronorite, breccia, norite, and diorite
domains. To date, economic Pd-rich mineralization has been discovered in both the breccia and
norite domains and occurs proximal to the contacts between the breccia and gabbronorite
domains and between the breccia and norite domains. The objectives of this study were to
i) evaluate the mechanisms of formation of the mineralized horizons near the contact between
the breccia and norite domains in the Offset and Creek zones of the SLDIC, and ii) assess the
tectonic setting in which the SLDIC formed. [...
Biological studies of muramyl dipeptide analogues as potential ligands for NOD2 receptor
Get PDFThe human body’s survival against various foreign disease-causing organisms solely depends on
the protection provided by our body's immune system. Our body's complex yet effective
immune system comprises cells, molecules and sensory receptors that can activate various
immune response pathways to eliminate pathogens. The innate immune system provides the first
line of defence through different types of sensor cells with pattern recognition receptors (PRRs)
with cytoplasmic proteins like NOD-like receptors (NLRs) that can activate the innate immune
system by recognizing the bacterial cell wall component peptidoglycan. The smallest known
fragment of peptidoglycan is Muramyl Dipeptide (MDP) which is recognized by the
Nucleotide-binding oligomerization domain (NOD2) receptor of the NLR family as a pathogenassociated molecular pattern and can immediately activate the human body's innate immune
system to release effective mediators that dominate the destruction of invading pathogens and
with adverse side-effects. The parent MDP molecule exhibits high toxicity, hydrophilicity, and
rapid elimination from the biological system. Modifications to the MDP structure without losing
their immunomodulatory properties can be evaluated to separate desirable biological activities
from unwanted side effects that can enhance and modulate the innate immune response and can
further be evaluated for their adjuvant potency in vaccines and drugs. [...
Magmatic minerals of the eastern Sunda arc, Indonesia
No full textThe eastern Sunda arc is one of the most prospective Cu-Au magmatic belts in the world with four world class copper-gold porphyry deposits: Batu Hijau (1.64 Gt at 0.44% Cu, 0.35 g/t Au), Elang (2.42 Gt at 0.31% Cu, 0.33 g/t Au), Tumpangpitu (1.90 Gt at 0.45% Cu, 0.45 g/t Au ) and Hu’u (1.70 Gt at 0.89% Cu, 0.49 g/t Au).
Magmatism along the belt spans the late Oligocene to Pliocene, with the majority of giant porphyry systems forming in the last 5 m.y. New geochronology confirms a consistent east-younging in central and eastern Java from Trenggalek (~15 Ma) through Salakan (~8.5 Ma) and Jember (~7 Ma), to the pre-mineralization phases (~6.5 Ma) and syn-mineralization phases (~4 Ma) at Tumpangpitu. ). New ages on Lombok show a westward younging in SW Lombok from Kuta, Plambik and Lembar in the east (20-17.5 Ma) through Songkang (~10-8 Ma), Selodong (~7.5 Ma) and Brambang (~7 Ma). On Sumbawa, there is a general younging from west to east from Nangka (~6.5 Ma), Naga Emas (~5 and 3.5 Ma) to Batu Hijau (~4.5-3.5 Ma) and the Elang district (~3.0 to 2.5 Ma). Middle-Micoene intrusions on Lombok (Lembar, Plambik, Kuta) were previously unknown, and extend the limit of Middle-Miocene magmatism to Lombok. [...
Power loss investigation in low power current source inverters using wideband gap devices for solar energy applications
Get PDFWith the steady expansion of renewable energy comes the need to develop next-generation power
converters focusing on high power density, efficiency, and reliability with lowered costs, simple structure,
and the ability to meet strict grid codes. Currently, Voltage Source Inverter (VSI) based solutions dominate the solar inverter market, however, the Current Source Inverter (CSI) introduces some interesting
advantages making the topology a valued research area. These advantages include inherent short circuit protection, natural voltage boosting capabilities, increased reliability, and increased power density.
However, CSIs suffer from significant conduction losses due to the need for reverse voltage blocking or
“reverse blocking” (RB) semiconductors and a large DC-link inductor with high losses. It is speculated
that Wide Bandgap (WBG) devices will push power converters to the “next generation”. Although, the
magnitude of WBG device advantages will depend on the ability of commercially available devices to
harness the benefits of WBG material, as well as the converter configuration. With the roll-out of commercially available WBG devices, their advantages should be able to naturally improve the base CSI’s
efficiency through a reduction in the RB switch’s conduction and switching losses. Also, by enabling
higher switching frequency operation, passive components can be downsized. This alleviates the DC-link
inductor size, cost, and power loss technical challenges seen in the CSI topology by a factor to be studied. [...
Effects of nitrogen supply on the physiological and morphological responses to elevated [CO2] in yellow birch (Betula alleghaniensis Britt.)
Get PDFOngoing climate changes can substantially impact soil nitrogen availability through its
effects on other environmental conditions such as temperature, precipitation, and the frequency
and intensity of extreme whether events, eventually altering the primary productivity of plants
and ecosystems. Effects of environmental changes on soil nitrogen cycling and availability vary
with among season and ecosystem. Nitrogen is a critical factor regulating the photosynthetic
responses of plants to elevated [CO2] as it is a main component in photosynthetic enzymes and
apparatus. Thus, changes in soil nitrogen availability will likely affect the ecophysiological
responses to climate change, particularly elevated [CO2] and the effects can change with species.
A good understanding of how nitrogen supply affects the physiological and morphological
responses of plants to elevated [CO2] is critical for predicting plant performance under future
climate conditions. This study examined the interactive effects of elevated [CO2] and nitrogen
(N) supply on the physiological and morphological responses in yellow birch (Betula
alleghaniensis britt.). Seedlings were exposed to two levels of [CO2] (ambient 400 µmol mol-1
versus elevated 1000 µmol mol-1
), and five levels of N supply (25, 50, 100, 150, and 200 mg N
L
-1
) for 4 months. Seedling height, root collar diameter, specific leaf area, biomass, biomass
allocation, and foliar gas exchange parameters were assessed. [...
Detection, identification, and mitigation of false data injection attacks and faults in vehicle platooning
Get PDFSmart vehicles are designed leveraging advanced hardware, including sensors, and cuttingedge technologies, such as artificial intelligence, Vehicle-to-Vehicle (V2V) communication, and Vehicle-to-Infrastructure (V2I) communication. These components are seamlessly integrated through software systems, empowering vehicle to make intelligent decisions and navigate safely in diverse environments.
V2V communication plays a vital role in facilitating information exchange among vehicles, encompassing crucial parameters, such as speed, acceleration, location, and vehicle
size. One of the key applications of V2V communication is vehicle platooning, where a
group of vehicles travels closely together, forming a cohesive convoy. Platooning has garnered significant attention due to its potential to revolutionize road safety, fuel efficiency,
and traffic flow. By reducing the distance between vehicles, platooning minimizes aerodynamic drag, leading to improved fuel efficiency and reduced emissions. Moreover, the
tight coordination and communication between vehicles enable enhanced safety through
faster reaction times and response capabilities. Additionally, platooning optimizes road
capacity and traffic flow, potentially alleviating congestion and enhancing overall transportation efficiency. [...
Yearning to learn: a pandemic-inspired approach to grief literacy
Get PDFThe COVID-19 global pandemic exacerbated and altered death- and
non-death-related loss, insisting that grief and bereavement adhere to protocols that were
unfamiliar and sometimes even prohibitive to moving forward in a healthy manner. As a
dying, death, and loss educator who explores grief using applied theatre methods with
children and adolescents, I responded to this recommendation by contemplating safe and
novel ways to provide acute support within these new and uncertain parameters. To meet the
long-term needs of the bereaved, development of grief literacy was recommended (Breen et
al., 2022).
When my beloved uncle Chris died unexpectedly on May 17th, 2020, I grappled to
negotiate my own pandemic-restricted grief. This caused me personal and professional angst:
if I, with the appropriate tools and strategies at hand, was struggling, how was I ever going to
be capable of holding space for others? I yearned to learn how to grieve in this new realm to
subsequently hold space for others and enrolled in an online workshop to learn about digital
storytelling.
This autoethnographic study examined my own pandemic-restricted grief experience
through the digital storytelling workshop’s process and product (digital story) as well
ascertaining its applicability in my applied theatre praxis within dying, death, and loss
education. [...
Harnessing generative AI for overcoming labeled data challenges in social media NLP
Get PDFWith the introduction of Transformers and Large Language Models, the field of NLP has significantly evolved. Generative AI, a prominent transformer-based technology for crafting human-like
content, has proven powerful skills across numerous NLP tasks. Simultaneously, social media
emerges as a rich source for NLP explorations, offering vast and diverse datasets that capture
real-time language usage, making it a valuable resource for understanding and advancing NLP
techniques. Given that supervised learning is the most popular Machine Learning training method,
numerous NLP studies necessitate labor-intensive annotation of social media text. However, despite the large amount of data available, the social media data annotation process is usually difficult
for human experts due to unique characteristics of text, such as shortness, lack of context, embedded socio-cultural perspectives, and varied writing styles. The challenges in constructing labeled
social media datasets often result in a scarcity of labeled data and the generation of low-quality
labels. Moreover, these datasets frequently face class imbalance due to the limitations of labeled
samples. Hence, ensuring a balanced, high-quality dataset in sufficient quantities is crucial for the
robust and accurate development of NLP models. To address these challenges, this study has identified the usage of generative AI for social media labeled text generation. Specifically, this study
focuses on two key objectives: augmenting existing labeled text samples and annotating unlabeled
text samples using generative AI. As the generative AI technology, the Generative Pre-trained
Transformer model, a prevalent choice for AI-based content generation is employed in different
versions throughout the study and evaluated its performance against traditional text augmentation
and annotation methods. While both studies centered around multi-class classification problems,
the text augmentation approach delves into augmenting human wellness dimensions using Reddit
posts, and text annotation tackles stance detection on abortion legalization using Twitter posts. By
employing various classifiers, the subsequent investigations aim to enhance classification performance in social media NLP, emphasizing the common goal of expanding labeled datasets, while
enhancing the quality of labels
Assessment of lake trout (Salvelinus namaycush) mercury concentration across a gradient of food web complexity and environmental variables
Get PDFExposure to mercury has been linked to health risks in both people and wildlife.
In Ontario, mercury pollution is to blame for 85% of the consumption restrictions on
fish from inland lakes. Heavy metals like mercury accumulate up the food chain.
Different rates of contaminant accumulation may be caused by variations in feeding and
food web biomagnification. To assess the role of food web biomagnification in an apex
predator, four distinct classes of lake trout (Salvelinus namaycush) prey with increasing
food chain lengths were compared to determine whether differences in food chain length
could account for the differences in muscle tissue mercury concentration. The analysis
for this study included fish, water chemistry, and mercury concentrations that were
collected from the IISD-Experimental Lakes Area (1973-2019) and the Ontario Ministry
of Natural Resources and Forestry’s Broad-scale Monitoring Program where the
Ministry of Environment and Climate Change analyzed the fish tissue. Accounting for
variation in fish body size, lake trout mercury concentration cannot be explained by food
chain length as predicted, although a significant interaction between body size and lake
class suggests there is a positive relationship with body size that varies based on food
web class. In attempt to contextualize this result, I examined the possibility that
environmental factors, such as lake chemistry (dissolved organic carbon, pH, total
dissolved phosphorus), and lake morphometry (i.e. maximum lake depth, surface area)
are also associated with variation mercury concentration. All environmental variables
examined show a positive correlation with mercury concentration; amongst the variables
assessed, dissolved organic carbon (DOC) had the strongest association with fish
mercury concentrations. Understanding the biotic and abiotic factors that influence
mercury accumulation can help make decisions on fish consumption guidelines and can
help further research opportunities
Assessing the vulnerability of south-central Ontario’s maple syrup industry to climate change: a multidisciplinary approach
Get PDFProductivity of Ontario’s maple syrup industry is tied to a specific climate window. As
climate continues to change, there is growing concern over the industry’s vulnerability given its
reliance on stable climate conditions for maintaining syrup quality and yield. Factors causing
variation in sap sugar content can differ at local and regional contexts and may change in relative
importance as climate change impacts regulating processes and mechanisms. Given the
ecological and socio-economic significance of maple syrup production in Ontario, the objectives
of this study were to: (a) determine which ecological factors are most important in explaining
variability in sap sugar concentration across south-central Ontario, (b) explore Ontario maple
syrup producer’s perceptions of climate change and identify the constraints to implementing
adaptation strategies that could help maintain current maple syrup production levels, and (c)
explore the influence of nature-based maple syrup recreational activities and tasks associated
with maple syrup production on individual well-being of adults with intellectual and
developmental disabilities (IDDs) at Camphill Communities Ontario (CCO). [...