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Contraction of ARF regulatory systems pre-dates parasitism in Fornicata
No full textGiardia intestinalis is an enteric pathogen with an extremely modified membrane trafficking system, lacking canonical compartments such as the Golgi, endosomes, and intermediate vesicle carriers. By comparison Giardia’s fornicate relatives possess comparatively greater endomembrane system complexity. In eukaryotes, the ARF GTPase regulatory system proteins, which consist of the small GTPase ARF1, and its guanine exchange nucleotide factors (GEFs) and GTPase activating proteins (GAPs), coordinate temporal and directional trafficking of cargo vesicles by recognizing and interacting with heterotetrameric coat complexes at pre-Golgi and post-Golgi interfaces. To understand the evolution of this regulatory system across the fornicate lineage, we have performed comparative genomic and phylogenetic analyses of the ARF GTPases, and their regulatory GAPs and GEFs in fornicate genomes and transcriptomes. Prior to our analysis of the fornicates, we first establish that the ARF GAP sub-family ADAP is sparsely distributed but present in at least four eukaryotic supergroups and thus was likely present in the LECA. Next, our collective comparative genomic and phylogenetic investigations into the ARF regulatory proteins in fornicates identify a duplication of ARF1 GTPase yielding two paralogues of ARF1F proteins, ancestral to all fornicates and present in all examined isolates of Giardia. However, the ARF GEF and ARF GAP complement is reduced compared with the LECA. This investigation shows that the system was significantly streamlined prior to the fornicate ancestor but was not further reduced concurrent with a transition into a parasitic lifestyle
Habitat Selection by Sandhill Cranes (Antigone canadensis) in Alberta using passive acoustics
No full textThe mid-continent population of Sandhill Cranes (Antigone canadensis) is the largest population of cranes in North America. Alberta has a large migratory Sandhill Crane population, with the Rocky Mountains acting as a choke point funneling birds through the province as they move north to the Canadian territories, Alaska, and Siberia. But Alberta has a small nesting population, and to date no studies have been conducted on nesting Sandhill Cranes in the province. Alberta’s Boreal Forest ecosystem varies substantially from southern Sandhill Crane nesting habitat and conventional nesting habitat selection may not apply to much of Alberta’s nesting population. The primary goal of this study is to reduce the knowledge gap surrounding Alberta’s Sandhill Crane population and what they require for breeding habitat. Using a systematic random sampling design, and autonomous recording units deployed by the Alberta Biodiversity Monitoring Institute, we demonstrated the viability of using passive acoustics to estimate resource selection functions to identify high-quality nesting season habitats in Alberta, while also determining the effects of weather on migratory behaviour. We estimated a resource selection function during the Sandhill Crane nesting season using a used/available design, while using k-fold cross validation to validate our map of the Sandhill Crane nesting habitats across northern Alberta. We then examined the effect of weather conditions on flight behaviour during the spring migration using a generalized linear mixed-effect model. Cranes selected for bogs and fens for breeding but avoided high canopy closure, areas of high forest harvest, and crop land. While on spring migration the cranes selected habitat similarly to the nesting season although they did not appear to be selecting against areas of forest harvest. We found that in tandem with selected landcover, a reduction in average daily barometric pressure from the day previous had the greatest grounding effect on migratory flight behaviour with the change in barometric pressure performing better than just landscape features alone, but the lack of covariate significance did limit our ability to make inferences on this effect. Our map of nesting season Sandhill Crane habitat can serve as an effective tool for understanding and preserving high quality Sandhill Crane habitat in Alberta, while the high predictability of our model illustrates the viability of resource selection functions with passive acoustic data
Experimental Research: Particle Image Velocimetry (PIV) Characterization of Fluid Rheology Influence on the Dynamics of Bed Erosion in Horizontal Pipes
No full textBed erosion refers to the controlled process of gradually removing particles from a stationary bed solely due to the shear forces exerted by flowing fluids. This phenomenon has various engineering uses, particularly when fluids flow over solid particles in horizontal conduits. Depending on the situation, it may be necessary to either initiate or prevent bed erosion. The management of river bed erosion, especially near water dams, involves efforts to minimize disturbance to the stationary bed. Conversely, other engineering contexts aim to trigger bed erosion to avoid partial or even total clogging in conduits or pipes, such as in rain drainage, wastewater systems, crude oil transport, and hole cleaning during drilling. This research will focus on hole cleaning during drilling, recognizing that each application involves different variables. Nevertheless, the fundamental erosion mechanism remains essentially the same across various applications.
Hole cleaning in highly inclined and horizontal wells is a complex process with many variables affecting the cuttings removal process, such as the density, flow rate, rheological properties, and type of drilling fluid, hole inclination angle, particle size and density, and drill pipe rotation speed and eccentricity. Although the effect of these variables on the efficiency of hole cleaning is known, field control of most of these variables is difficult. Considering their potent effects on hole cleaning and relative ease of control, the most critical variables are drilling fluid flow rate and rheological properties. Therefore, understanding fluid-particle interaction and how drilling fluid velocity and rheological characteristics affect particle removal from bed deposits (bed erosion process) is the key to designing and developing an optimum hydraulics program for effective hole cleaning.
The bed erosion performance of 17 different fluids is examined at a constant bed height of 11 mm to capture the onset velocity of the fluids with distinctive rheological models. The 17 testing fluids consist of ten Newtonian fluids (1.0 cP<μ_N<40.0 cP), three PL fluids (0.61>n>0.44 ; and 0.3<K<3.0 Pa.s), and four YPL fluids (0.68>n>0.49 ; 0.17<K<2.0 Pa.s; and 1.0<τ_YS<5.6 Pa). Regardless of fluid rheology, the Reynolds number evaluated at the bed erosion onset velocity is inversely proportional to fluid viscosity, following a unique power law correlation based on fluid rheology. In other words, the higher the fluid viscosity, the lower the Reynolds number needed to initiate bed erosion (i.e., onset velocity). It is observed that the onset velocity for bed erosion is inversely proportional to fluid viscosity (μ) in non-Newtonian fluids (i.e., PL and YPL). In contrast, for Newtonian fluids, the onset velocity is directly proportional to viscosity, which is a major finding of this research for Newtonian fluid mechanics. Typically, it is accepted that the drag coefficient (C_D) is directly proportional to fluid viscosity (μ) when all other parameters are fixed, but this is inconsistent with experimental results for Newtonian fluids regarding bed erosion. That is, the higher the Newtonian fluid viscosity (μ) used to erode a sand bed, the higher the velocity needed to initiate the bed erosion process.
A derived criterion for the drag coefficient ratio provides a quantitative way to compare bed erosion performance across different rheologies by measuring local velocities near the stationary bed at 1.0 mm above the mean bed height. The drag coefficient ratio shows that YPL fluid performs better than both PL and Newtonian fluids when apparent viscosity (μ) is matched in terms of pressure gradient and lower onset velocities. Furthermore, the introduced criterion resolves the contradiction with the drag theory for Newtonian fluids discussed earlier. It was also used to demonstrate the positive influence of yield stress on improving bed erosion performance. For the first time in bed erosion research, it was shown that bed erosion performance exceeds that of Newtonian fluids when apparent viscosities are equal. While water outperforms all non-Newtonian fluids, this advantage is due to its lower viscosity, not rheology type. Therefore, the idea that Newtonian rheology is superior to non-Newtonian fluids has been shown to be invalid when apparent viscosity (μ) is systematically matched
DALAM Launches Digital Library
No full textThis article describes the newly launched DALAM Digital Library, designed to supply resources to information professionals who are working with the decolonization of metadata. The Library has four sections: Educational Resources, Research Resources, Dictionaries, Thesauri and Subject Headings, and Maps and Place Names
Study of ultrasound processing on oat beverage quality and the value-added application of oat pulp fiber
No full textOat beverage has rapidly gained popularity among consumers due to growing awareness of dairy-related allergies, environmental sustainability, and the health benefits associated with plant-based food consumption. Despite this increasing demand, the oat beverage industry faces significant challenges, including how to improve the nutrient recovery from the oat grains and how to add value to the by-product, oat pulp. This thesis aimed to address these issues with two specific objectives: 1) to enhance the nutritional, physicochemical, functional properties of oat beverages via ultrasound pre-treatment, and 2) to explore the value-added application of insoluble dietary fiber (IDF) derived from oat pulp as a functional ingredient in plant-based yogurts.
In the first objective, ultrasound treatment was investigated as a novel pre-treatment technique to enhance the nutritional recovery, particularly focusing on β-glucan and protein, in oat beverage. Ultrasound was applied at various power levels (60, 240, and 960 W) and treatment durations (1, 5, and 9 min). The findings demonstrated that ultrasound effectively disrupted oat cell walls, significantly enhancing β-glucan extraction by up to 39% at an optimal power level of 240 W for 9 minutes. Importantly, ultrasound treatment exhibited minimal impact on β-glucan molecular weight, thus preserving its inherent health benefits. Although ultrasound treatment did not significantly enhance protein content, it altered the oat protein structure by increasing surface exposure of hydrophobic groups, subsequently improving foaming properties. This improvement holds substantial promise for applications in coffee beverages and oat-based desserts. Additionally, ultrasound-treated oat beverages retained desirable shear-thinning behavior, beneficial for industrial processing and maintaining desirable mouthfeel characteristics.
The second objective addressed the challenge of oat pulp utilization by modifying oat IDF through autoclave-NaOH treatment to enhance its physicochemical and functional properties. Results showed distinct alterations in oat IDF properties, including a larger particle size, reduced crystallinity, increased hydrophilic group exposure, and improved water-holding capacity (WHC). When oat IDF was incorporated into lentil-based yogurt formulations at five concentrations of 0.2–1.0% w/w, a significant improvement in WHC and reduction in syneresis were observed. Microstructural analysis further revealed a denser protein network, with 22% higher link density and approximately 50% lower pore fraction at the optimal concentration of 0.6% w/w oat IDF. Oat IDF acted as both a filler and a bridging agent, interacting electrostatically and through hydrogen bonding with proteins to reinforce the protein matrix. Enhanced rheological properties, including increased viscosity, improved firmness, and greater resistance to deformation under high shear conditions, were also observed, highlighting the potential of oat IDF in improving the structural integrity and rheological properties of plant-based yogurts.
Overall, this research provides novel insights into enhancing the nutritional value of oat beverages. In addition, it proposes a strategy for valorizing oat IDF from the pulp. Ultrasound pre-treatment promoted the release of β-glucan with minimal depolymerization and promoted protein partial unfolding to improve foaming properties, beneficial for formulating coffee beverages and desserts. Moreover, the application of autoclave-NaOH treated oat IDF promoted filling and bridging effects to improve protein structural integrity and resistance to deformation, along with improving WHC and reducing syneresis of lentil-based yogurt. These findings contribute substantially to the development of sustainable food processing practices, offering both environmental benefits and improved nutritional profiles in plant-based food products
Fault Classification and Prediction for Gears and Bearings by Data-Driven Method
No full textFault diagnosis and the prediction of remaining useful life (RUL) are critical for the safety and reliability of rotating machinery. This is especially true for applications involving gearboxes and bearings, which are commonly found in the aerospace, energy, and manufacturing sectors. These components frequently function in tough, unpredictable conditions where unexpected faults or deterioration can lead to severe failures and significant maintenance expenses. Thus, having precise, prompt, and sturdy diagnostic and prognostic tools is crucial for executing condition-based maintenance approaches. Traditional data-driven techniques have demonstrated potential in fault classification. Nonetheless, their effectiveness is highly reliant on extensive labeled data, which is often unrealistic in practical situations. Additionally, while sophisticated few-shot learning approaches aim to address this, they frequently exhibit inconsistent performance with limited data, thereby weakening their ability to generalize. Moreover, most classification models view all fault types uniformly in terms of feature selection, neglecting the unique signal characteristics of different fault types that necessitate customized feature representations. Conversely, many RUL prediction models rely heavily on the monotonicity of selected features, often neglecting sudden health deterioration in mechanical components.
This study aims to procure some insights into fault classification and prediction for gears and bearings with data-driven method. In relation to fault classification, this thesis enhances feature selection algorithms within data-driven methodologies and proposes innovative neural network frameworks in few-shot learning and physics-informed neural networks. Subsequently, a novel RUL prediction framework is introduced for predicting bearing fault. Initially, in order to address the feature optimization for sub-model in hybrid diagnostic models, a Block Feature Selection (BFS) method has been proposed. Within this framework, each sub-classifier is optimized for a particular fault type using the Non-dominated Sorting Genetic Algorithm II (NSGA-II) and a custom sorting algorithm, thereby facilitating the selection of optimal feature groups specific to each fault type. The selected groups are subsequently integrated to form a cohesive yet specialized feature space for the hybrid model. Experimental validation conducted on planetary gearbox datasets, including scenarios with added white noise, substantiates the robustness and efficacy of the BFS approach in multi-fault diagnosis. Secondly, to address the issue of data limitation, a novel Wavelet Transform Prototypical Network (WTPN) is proposed. This network converts one-dimensional vibration signals into two-dimensional distance matrices using discrete wavelet transform, which enhances feature discrimination within the embedding space of prototypical networks. A confidence weighting mechanism improves classification consistency by assigning reliability-based weights to various decomposed signal bands. Experimental results and public datasets indicate that WTPN surpasses existing few-shot learning methods in accuracy and stability, positioning it as a strong solution for scenarios with limited annotated data. Thirdly, to avoid RUL predictions that highly rely on degradation trends, a Critical Point Detection (CPD) mechanism based on prototypical networks has been developed. This method identifies abrupt changes in health status and adjusts the network’s hyperparameters post-detection, allowing for accurate predictions of the remaining lifespan after each critical transition. The process iterates as new vibration data comes in, adapting to the dynamic behavior of the system. Benchmark results indicate that CPD significantly enhances the precision of RUL predictions, providing a novel paradigm for adaptive prognostics. Finally, to address the limitations of traditional PINNs in coping with different operational conditions, a novel Ensemble Multi-Loss PINN (E-MLPINN) is proposed. This method eliminates the need for pre-calculated fault characteristic frequencies by uncovering latent variable relationships through dual-output neural networks. An ensemble structure that integrates multiple loss functions, optimized via random sampling and cross-training, assures diagnostic reliability. Final classification is conducted using Gaussian kernel density estimation based on the learned frequency-related features. Validation against experimental and public datasets showcases the enhanced accuracy and adaptability of E-MLPINN in various working conditions. This thesis research focuses on data-driven methods to address fault classification and prediction challenges in gears and bearings. Then, the developed approaches improve the accuracy and robustness of models by improving feature selection method based on NSGA-II and proposing specialized novel neural network frameworks for few-shot learning and PINN. Furthermore, future research will investigate fault diagnosis and prognosis in more complex scenarios, including multi- source input environments and lacking specific fault types in model training
A Scoping Review and Keeoukaywin; Exploring Non-Indigenous Health Educators Experiences Implementing Indigenous Health Content in Health Science Curriculum
No full textPurpose: The purpose of this research is to better understand what is known about the experiences of non-Indigenous educators in the Health Sciences who are tasked with developing and/or delivering Indigenous health curriculum. There are challenges and barriers faced by non-Indigenous educators in the health sciences which impact their ability and/or willingness to implement Indigenous health content within their respective faculties. Acquiring a more comprehensive understanding of the obstacles would benefit the future implementation of Indigenous health content in the Health Sciences.
Methods: This research employed a two-eyed seeing approach, comprising a scoping review and Keeoukaywin (The visiting way). The scoping review will provide a framework to categorize, synthesize, and understand existing literature. The Keeoukaywin (The visiting way) will use Indigenous methods to guide the researcher in interpreting the themes and incorporating stakeholder knowledges, aligning with the investigator's way of knowing. First, a scoping review was carried out to understand what available research evidence exists on the topic of non-Indigenous educators working in the Health Sciences who have been working to develop and/or deliver Indigenous health content. The scoping review followed the five stages as outlined by Arksey and O’Malley: clarifying and linking the purpose and research question; balancing feasibility with breadth and comprehensiveness of the scoping process; using an iterative approach to selecting studies and extracting data; incorporating a numerical summary and qualitative thematic analysis, reporting results, and considering the implications of study findings to policy, practice, or research. Followed by contextualizing the findings through utilizing the Keeoukaywin, an Indigenous methodology, with non-Indigenous educators working in the Health Sciences who have experience implementing Indigenous health content. Results: 27 items were included in the scoping review, and using thematic analysis, the following themes were identified: Reconciliation, reflection and reflexive practice, discomfort, accountability and responsibility, allyship and finally community involvement. This was contextualized by the experiences of two non-Indigenous educators working in the Health Sciences, utilizing a visiting methodology. The visit highlighted similar themes of self-reflexivity, responsibility, accountability, community, positionality, relationship, and gratitude, with responsible allyship underlined in all areas.
Conclusions: The scoping review and the experiences shared through Keeoukaywin (The visiting way) by non-Indigenous educators working to develop and/or deliver Indigenous health content in the health sciences highlight challenges and areas of support that could be addressed to further the work of non-Indigenous educators who are attempting to enact reconciliatory practices within health science education
Constraints on the distribution, composition, and lithology of eclogite and pyroxenite from the central Slave craton
No full textWe investigate the petrogenesis of a newly collected suite of 225 barren and one diamond-bearing eclogite and pyroxenite microxenoliths from the A154, Panda, and DO-27 kimberlites from the Lac de Gras region, Northwest Territories, Canada. All samples contain low-Cr garnet (Cr 2 O 3 < 1 wt%) and were analysed for major-element compositions of garnet and clinopyroxene. Trace-element compositions were determined for 140 mineral pairs, and δ 18 O values for garnets from 160 samples. Geothermometry indicates that eclogite and pyroxenite xenoliths from A154 are distributed throughout the subcratonic lithospheric mantle (SCLM), from ~ 80 km to as deep as ~ 200 km. Eclogites/pyroxenites from A154 that equilibrated shallower than ~ 170 km are derived from a variety of protoliths including basaltic- and cumulate-type oceanic crust. The majority of these rocks have δ 18 O values (average + 5.54 ± 0.89‰, 2σ) within or below the canonical mantle range. The deeper suite of eclogites (≥ 170 km) typically have Ca-rich oceanic cumulate-type protoliths, with garnet δ 18 O values (+ 4.95 ± 0.58‰) mostly below the mantle range. Eclogite/pyroxenite microxenoliths from Panda and DO-27 have protoliths that include basaltic- and cumulate-type oceanic crust. Oxygen isotope compositions for low-Cr garnets from DO-27 have a similar distribution to A154 whereas those from Panda are largely within or near the mantle range. Our expanded dataset shows that eclogites are key components in mantle root assembly, and reinforces previous findings of a lithological, mineralogical, and compositional boundary at approximately 170 km depth in the Slave craton lithosphere