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Using Implantable Tags to Investigate the Free-Swimming Activity and Bioenergetics of Largemouth Bass and Lake Trout
No full textAccurately assessing free-swimming activity, energy use, and behaviour remains challenging, but is important in advancing our ability to predict factors that influence movements, foraging, reproduction, and survival. These measurements are also valuable to improve bioenergetics models which rarely incorporate free-swimming measurements. Tagging devices may be used to estimate these endpoints; however, this requires prior calibrations which relate recordings of activity, metabolism, or the target behaviour to tag recordings (e.g., acceleration). I my thesis, I sought to 1) expand the scope of free-swimming measurements that can be collected from tagged largemouth bass (Micropterus nigiricans) and lake trout (Salvelinus namaykush) using swim performance and behavioural calibrations, 2) advance our understanding of their free-swimming activity and energy use, and 3) improve their bioenergetics models. Additionally, as winter-specific bioenergetics measurements are presumably lacking, throughout my research there is an emphasis on winter or cold-water. To contextualize the importance of cold-water bioenergetics research, I reviewed existing literature on cold-water bioenergetics research in freshwater fish. My results indicated that there was a lack of cold-water bioenergetics measurements for certain parameters and that less than half of the bioenergetics models reviewed included cold-water measurements in their derivations. Using swim tunnel respirometry, I produced calibrations which allow the estimation of swimming speed and metabolism in free-swimming lake trout and largemouth bass across an environmentally relevant range of temperatures. I later assessed largemouth bass’ overwinter activity and energy use, estimated using my previously derived lab calibrations. Generally, activity, heart rate, and metabolic rate decreased with fall cooling, remained low over the winter, increased with spring warming, and peaked in the late spring coinciding with their spawning period. Bioenergetics modeling indicated that bass engaged in overwinter feeding to explain observed weight changes which were highly variable. I also explored whether tags could be calibrated to predict sea lamprey attacks on free-swimming lake trout. Predictive models produced were able to identify periods when sea lamprey were attached to trout with reasonable accuracy but data noise caused by tag movement within the body seemed to impair model performance. Modifications to the surgical procedure may improve model accuracy if further developed
Exploring User Experience, Accessibility, and Privacy Preserving Techniques in a Non-Medical Assessment Tool for Cognitive Function
No full textNowadays, there is a growing interest in mental health screening tools which can be attributed to a rising adoption of digital health technologies. In our research, we developed BrainBoost5, a non-medical assessment tool which focuses on mental health and cognitive function with the purpose to better understand and support mental well-being for both users and stakeholders. Our tool integrates privacy-preserving techniques to securely share assessment results while safeguarding personal data. We utilized anonymization techniques specifically pseudonymization, generalization and suppression to protect the confidentiality of individual’s data. To evaluate our proposed solution, we undertake a user study to explore our tool's usability, accessibility, and anonymization techniques when sharing results. Additionally, we conduct an analysis of our tool’s accessible features, complexity, and a comparative study with other existing solutions
Does Emotion Regulation Help Us Pursue Our Goals? Adaptive and Maladaptive Strategy Use and Everyday Goal Progress
No full textResearch on personal everyday goals (e.g., make friends) has mainly focused on the effectiveness of self-control strategies for making progress. While one reason people experience self-control challenges (e.g., temptations, procrastination) is poorly managed mood, there is a lack of research examining how emotion regulation specifically impacts the progress of everyday goals. Using a longitudinal experience sampling method and daily diary design, 317 participants reported their emotion regulation across 14 different strategies and goal progress over a seven-day period, then at one and three-month follow-ups. A greater use of adaptive emotion regulation strategies positively predicted nightly (between persons) and follow-up goal progress, while a greater use of maladaptive strategies did not. The effectiveness of a strategy generally did not depend on the intensity of negative emotions. Out of 14 strategies, reflection was found to have the largest positive impact, highlighting a particularly effective approach to emotions that facilitates goals
From Turtle Island to Vistula’s Shores: Indigenous North American and Eastern European Futurisms in Dialogue
No full textThis dissertation imagines the possibilities of Indigenous North American and Eastern European artistic dialogues as a form of solidarity. The artists are examined through four chapters that touch upon themes of reinventing traditional stories and legends (Chapter Two), environmental issues as dystopias (Chapter Three), and futuristic folk practices (Chapter Four, Parts One and Two). Each chapter presents artists and filmmakers from different Indigenous and Eastern European communities, paired with activists and theorists that discuss: survivance, Sorrowfuturism, Hungarofuturism, Ethnofuturism and Indigenous futures with specific focuses on particular Indigenous nations and their unique perspectives. There are theories unique to each chapter, such as the concept of “care” not just caring for community, but caring for traditions and culture as seen in Chapter Four, Part One. Also, discussions of environmental issues in the anthropocene (Chapter 3) or the introductory chapter showcasing the existing relationships between Indigenous and Eastern European communities. Visualizing culture and traditional stories in the future, through a speculative lens, while also using pop culture characters to address topics around colonialism and imperialism can be found in the second chapter. Finally, folk practices and regalia in speculative worlds and spaces (Chapter Four, Part One) precedes the examination of more radical acts of folk art that confront dangerous ideologies and counter oppressive systems that target Indigenous sovereignty, LGBTQ+ communities and women's rights (Chapter Four, Point Two)
Optimization of primary beam for x-ray dual-mode imager comprising radiography and coherent scatter
No full textMedical, industrial, and security x-ray systems should give images that demonstrate material contrast for accurate identification. Novel devices use both coherently-scattered x rays and primary to acquire images. In our system, the same detector is used for primary and scatter. The primary information being detected post object must be attenuated so that both the primary and scatter are within the detector’s dynamic range. Initially, we used 1.5-mm-thick post-object attenuator disks of 90% tungsten/10% copper alloy. In this work, we investigate whether reducing the incident beam’s x-ray tube potential and using less attenuating materials can increase primary image quality. Our final attenuating material is 1.0 mm cerium. This scales all three of primary signal-to-noise-ratio, signal size, and signal-difference-to-noise-ratio by approximately a factor of 10. The scatter values remained relatively unchanged. Additional filtration placed upstream at the collimator could bear further investigation
Subwavelength Gratings Engineered 90 degree Optical Hybrid Component for Coherent Detection
No full textCoherent detection is essential in optical communications, enabling efficient long-distance data transfer and sensing. Heterodyne detection, with its high sensitivity and spectral efficiency, relies on a 90-degree optical hybrid to demodulate signals. Multimode Interferometers (MMIs), particularly 2x4 MMIs, are popular for this purpose due to their fabrication tolerance. Subwavelength Gratings (SWGs) enhance MMIs by providing low loss and broadband operation. This study presents two SWG-based 2x4 MMI designs—linear and parabolic tapering—operating at central wavelength of 1550 nm on a silicon-on-insulator platform. The linear design measures 61.94 um, while the parabolic design is 59.5 um. Both devices offer minimal loss, a CMRR over -20 dB, phase deviation within ±2°, and imbalance below ±1 dB across the 1.45 um–1.65 um range. The parabolic design reduces device length by 20.24%, and the linear by 14.32%, compared to rectangular MMI designs
Accumulation by Dispossession: An Analysis of Social and Economic Reforms in Ukraine
No full textMy dissertation examines the impact of neoliberal reforms on the socioeconomic sphere in post-Soviet Ukraine, and discusses their implications for the standard of living of citizens. The independence of Ukraine from the USSR initiated the ascendance of a very affluent Ukrainian capitalist class in a short period of time. The disassembly of socialist welfare, however, took much longer. I introduce the concept of "socialist residualism" to make sense of the resistance to neoliberal encroachments on Ukraine's institutions and social logics. I trace socialist residualism through several distinct periods in independent Ukraine, as the introduction of capitalism there was imbued with unique characteristics that differed from post-Soviet states that moved much faster to shed their socialist social and economic relations. The events of 2014 marked an institutional rupture accelerating the accumulation by dispossession of public and state assets, and strengthened the recommodification of labour and the social sphere. I employed semi-structured interviews to investigate changes to Ukrainians' socioeconomic welfare in the Central and Western regions of Ukraine in the periods from 2016 to 2022. My first case study analyses the changes to social reproduction in the rural and agricultural region, including the development of land as a form of social security for women and their families. The second case study explores the loss of a wide range of public services associated with the dismantlement of a city-forming enterprise, which impacted the city as a whole, and its residents, in particular
Fault Tolerant, Adversarial and Highly Available Lithium Batteries Health Monitoring Framework
No full textLithium batteries are becoming highly popular and used as a viable renewable energy source to compensate the shortage of other energy sources such as fossil fuels. Batteries are subject to external events such as collisions, shocks and vibrations and internal events such as overcharging, excessive discharging that can cause batteries to malfunction. One of the main external events that cause direct failure of lithium batteries are failure related to sensors, knowingly: Temperature, Voltage and Current. Batteries failures, especially at the sensors level represent a major challenge for battery health monitoring frameworks. Wireless BHM frameworks are becoming more popular which exposes them to malicious cyber attacks threatening the reporting accuracy of underlying BHM frameworks which can cause life threatening harm especially in systems such as aircrafts or medical implantable cardioverter defibrillator. It becomes crucial to implement BHM frameworks that relies on sensor readings to accurately predict batteries metrics such as state of charge (SOC), state of health (SOH) and remaining useful life (RUL) while been fault tolerant to any sensor failure, highly available by keeping sensor readings available even if sensors are deemed nonoperational, finally, adversarial to any potential cyber attacks especially in the era of wireless BHM frameworks. Our main contribution in this thesis is to offer a BHM framework that is equipped with a fault detection and isolation module that reports any sensor malfunction to a prognostic accurate, fault tolerant, adversarial and highly available module. The four key attributes, knowingly, accuracy, fault tolerance, adversariality and highly availability makes the proposed BHM framework robust, agile and more reliable to work in extreme conditions where battery sensors are subject to external hazards. The proposed prediction models’ effectiveness was evaluated using two batteries datasets, the first one is developed by NASA and the second one is developed by Toyota research institute. Testing the proposed predictive models against large datasets prove that the models are robust and their prediction accuracy does not decrease with data volume. The performance of the suggested prognostic frameworks was evaluated using the error indicators Mean Absolute Error (MAE), Root Mean Square Error (RMSE) and the R square (R2)
A look inside the net: using social network analysis to investigate freshwater turtle feeding aggregations
No full textSociality, the tendency for animals to live in groups, is influenced by ecological and evolutionary processes at every level of organization. In vertebrates, sociality exists as a spectrum, not a dichotomy. Despite this, non-avian reptiles are often incorrectly assumed to be non-social. I investigated signatures of social structure in feeding aggregations of three species of freshwater turtles caught in baited traps. I found that turtles were significantly clustered spatially and temporally in traps and were positively assorted with their conspecifics. Of the species studied, painted turtles (Chrysemys picta) were most often co-captured with other individuals. Furthermore, these turtles showed no evidence of intraspecific sex assortment and no within-species relationship between an individual's body size and the number of co-captures. These results expand our understanding of turtle sociality, can further our understanding of the ecology and evolution of sociality in vertebrates, and highlight avenues for future research