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Crafting Bodily Infrastructures: Cripping Off-Earth Futures
No full textAmidst a resurgence of enthusiasm for outer space travel and the simultaneous rise of narratives attending to speculative future narratives in the early 2020s, this dissertation outlines the political potential of crip bodies living on the margins of Earth as a site to reconceive the relationship between the body and outer space. With a focus on disability, this dissertation reveals how NASA and ESA's proposed futures require a restrictively narrow view of the human body. These agencies insist that they are creating accessible, inclusive visions of outer space; however, they require an idealized and unrealistic body based on medicalized and eugenic ideals. This dissertation offers a new conceptual category I term the ciscyborg to address how this body has remained safely unquestioned within scientific fields. The ciscyborg is enabled by infrastructure that accommodates and amplifies a complex able bodied relationship with time while aboard spacecraft. As value is often tied to economic progress, temporal differences experienced in off-Earth spaces serve as a justification to exclude the presence of disabled bodies within a limiting public narrative. I shift attention from space to time in order to identify the temporal differences enabled by outer space infrastructure. For example, I offer the time-suit as opposed to a space suit in order to investigate how bodies navigate time off-Earth and to understand the nuanced way ciscyborgs are integrated into outer space environments. I indicate the specific mechanisms that construct and enforce disability aboard spacecraft, which include historical precedent, technical design and medicalization of bodies, all of which hinder the progress of inclusivity initiatives. Beyond this, I bring into focus an aesthetic motif that already exists within images of outer space, which I call aesthetics. This motif highlights visual elements that signify disability on Earth such as adaptive devices, and indicates that they are celebrated as signifiers of able bodies in contemporary spaceflight. Examples of this include adaptive zero-gravity physical training devices, support crews, and life support systems that serve as accommodation for ciscyborgs. Highlighting this contradiction allows me to think alongside Afrofuturists, queer futurists, and Indigenous futurists, all of whom use aesthetic elements encoded in technology to speculate about divergent and equitable futures. The fact that distant futures are imagined as being free of disability, and near futures are full of aesthetics, indicates that accommodation for disabled bodies in spaceflight is not only possible, but is occurring right now for ciscyborgsPh.D
Towards Real-world Social Robot Navigation with Deep Reinforcement Learning and Imitation Learning
No full textDeep Reinforcement Learning (DRL) and Imitation Learning (IL) are promising approaches for learning socially compliant robot-navigation behaviors. These methods enable policies to be learned directly from interaction, avoiding the need to explicitly model human behavior. We propose a decision process formulation that unifies path tracking and human avoidance within a corridor abstraction. We develop a real-time, single-sensor system with robust perception-to-control integration for reliable deployment. We then introduce Deep Residual Model Predictive Control (DR-MPC), a sample-efficient DRL method that leverages MPC-based path tracking. DR-MPC significantly outperforms classical and residual DRL baselines in simulation, and we further validate its feasibility by training it directly in the real world. Lastly, we identify key architectural and training decisions that substantially improve Behaviour Cloning, achieving a three-times improvement in success rate. While these results are promising, challenges remain in reducing real-world data requirements and capturing the multi-modal nature of social navigation.M.A.S
Dynamic Flexible Job Shop Scheduling via an Adaptive Genetic Algorithm and Deep Learning
Get PDFTo address the scheduling problem of dynamic flexible job shop, this study proposes a hybrid scheduling method that integrates an adaptive genetic algorithm, dynamic target smoothing, and a deep Q-network (DQN). The scheduling process is formulated as a Markov decision process, where a graph convolutional network (GCN) extracts feature representations from evolving job and machine states. The adaptive genetic algorithm dynamically generates target values, while the dynamic target smoothing mechanism—based on sliding windows or exponential smoothing—further stabilizes target updates and enhances training efficiency. Experiments on the Brandimarte benchmark with stochastic job arrivals show that the proposed method reduces makespan by up to 2.1% compared to the QNGA baseline. In addition, the integration of adaptive evolution and smoothed target learning provides more stable training and stronger adaptability to dynamic environments than the existing DQN-based approaches
THE INFLUENCE OF LINEAR FEATURE WIDTH ON SMALL MAMMAL COMMUNITIES IN NORTHEASTERN ALBERTA
Get PDFAnthropogenic linear features, such as seismic lines, pipelines, and powerlines, are widespread in the boreal forests of western Canada. Although these corridors are widely recognized as drivers of habitat loss and fragmentation, the extent of their impact is likely depending on their width. Understanding how linear feature width influences small mammal communities is important for informing more effective management and restoration efforts. We deployed remote cameras at 354 sites across a gradient of soft (vegetated) linear feature widths (3–150 m) and paired each site with forest interior control sites. We recorded twelve small mammal species. Community-level analyses showed that forest-affiliated species were associated with narrower features and forest interiors whereas open habitat species showed the opposite pattern. Species-specific models indicated that four of nine analyzed species showed significant negative responses to increasing width. No species showed a significant positive response to width. Contrary to expectations, wider features were not more likely to be occupied by early-successional species but showed reduced overall small mammal use. Our findings indicate that wide linear features may act as ecological barriers for small mammals and suggest that minimizing linear feature width and/or promoting revegetation could mitigate impacts on small mammals in the boreal forest.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
High-Throughput Structure Determination Using Serial Electron Diffraction Method
Get PDFAtomic structure determination is central to understanding the physical, chemical, and functional properties of materials. Traditional crystallographic methods such as X-ray diffraction (XRD), or Cryo-Electron Microscopy (CryoEM) require well-ordered, micron-sized crystals and often involve cryogenic environments, limiting their applicability to many important classes of beam-sensitive or nanoscale materials. Electron diffraction has emerged as a promising alternative, particularly for nanocrystals, due to the strong interaction of electrons with matter and their lower radiation damage per scattering event compared to X-rays. This thesis presents the development and application of a high-throughput, room-temperature method for structure determination using Serial Electron Diffraction (SerialED) in a scanning transmission electron microscope (STEM).SerialED enables single-shot diffraction data acquisition from randomly oriented nanocrystals, significantly reducing radiation damage while eliminating the need for sample tilting. The method was implemented on a readily available TEM using a collimated nanobeam and fast direct electron detector. A fully automated data collection protocol was developed, involving low-dose STEM imaging for crystal mapping and nanobeam targeting, followed by sequential diffraction acquisition. Custom software and data analysis pipelines were created to refine beam centers, correct geometric distortions, and index diffraction patterns.
The methodology was validated through the successful room-temperature structure determination of diverse materials, including two metal organic frameworks (ZIF-8 and HKUST-1), a pharmaceutical compound (carbamazepine), a perovskite (Cs₄PbBr₆), and a spin-crossover complex ([Fe(Qsal)₂](NCS)). Additionally, the in situ structure of a volatile organic crystal (anthracene) was solved using Formvar encapsulation. A Faraday cup system was also developed for accurate electron dose measurements, and radiation damage studies were conducted on organic nanocrystals.
This work establishes SerialED as a practical and accessible technique for high-resolution structure determination using standard TEM instrumentation. It opens the door to in situ, time-resolved, and low-dose structure determination of nanocrystalline materials and offers a scalable path toward microscale crystallography using minimal sample quantities. Future integration with microfluidics, automation, and pump–probe methods is expected to further broaden the impact of SerialED across structural chemistry, materials science, and biology.Ph.D
Devices, Circuits, and Architectures for Monolithic Quantum Computing Processors in Advanced Production CMOS Technologies
No full textThis thesis presents characterization and design work towards the implementation of a monolithically-integratedquantum computing processor based on electron/hole-spin qubits hosted in semiconductor coupled-quantum dot
arrays manufactured in production CMOS processes. As a result of this work, a production CMOS technology
can now be used to manufacture both the quantum dot arrays and the classical qubit control/readout electronics
together on the same die and operate them together at the same 2 – 4 K temperature.
The DC to 70 GHz performance of transistors and passives from advanced production 22nm FDSOI CMOS,
55nm SiGe BiCMOS, and 7nm, 5nm, and 3nm FinFET were characterized over temperature from 400 K to 2 K.
Technology figures-of-merit relevant to analog, RF, and digital circuit design were found to improve at cryogenic
temperature, with technology trade-offs being similar over temperature. It was found that peak fT and peak fMAX
current densities are constant over measured temperatures in all 4 CMOS technologies and slightly different for the
SiGe HBTs in the BiCMOS technology. Noise in SiGe HBTs is characterized over bias, showing a ∼10× smaller
minimum noise current density at 2 K compared to 300 K.
Next, large 1-dimensional and 2-dimensional coupled-quantum dot arrays with 1024 and 2048 (respectively)
quantum dots were manufactured in the 22nm FDSOI CMOS technology, both with Si and (for the first time) SiGe
channels. Measurements of smaller, 1x4 and 2x4 arrays show < 0.2 fA gate leakage current in quantum dots
as small as 18nmx15nmx6nm and with spacing as small as 40 nm. Coupling between adjacent quantum dots is
demonstrated for the first time to be electrically tunable via a selective n- or p-well backgate. The impact of gate
oxide thickness, Vt option, top gate dimension, and top gate spacing is measured and discussed.
Lastly, an ∼80-GHz PLL circuit needed for the quantum processor was implemented in 22nm FDSOI CMOS
and characterized over temperature. The RMS jitter of the PLL integrated from 1 kHz to 1 GHz improves from
48.6 fs at 300 K to 24.3 fs at 50 K, resulting in theoretical quantum gate operation error less than 10^−4.Ph.D
Phenotypic and Transcriptomic Changes in Acinetobacter baumannii in Rich and Minimal Growth Mediums
Get PDFAcinetobacter baumannii is an opportunistic pathogen that is often studied in commonly used rich media in laboratories worldwide. Due to the metabolic versatility of A. baumannii, it can be cultured in different growth mediums; however, this can lead to genotypic and phenotypic variations. In this study, we compared phenotypic and transcriptomic changes in A. baumannii ATCC17978 VUcultured in M9 minimal media supplemented with 20 mM sodium succinate and rich lysogeny broth media. Phenotypically, growth was significantly slowed, virulence in Galleria mellonella was attenuated, and susceptibility to a variety of antibiotic classes was reduced when A. baumannii ATCC17978 VU was grown in minimal media versus rich media. Transcriptomic analysis showed differential regulation of >700 genes—including those associated with energy production and ribosomal function—when the two growth conditions were compared, with the majority of the upregulated genes seen in minimal media of unknown function. This study showed that culture media has a profound effect on the phenotype and cellular workings of a bacteria, highlighting the need for more studies of pathogens like A. baumannii ATCC17978 VU in minimal media.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
SP Testing Backend Ingest! Hello Hello! s
No full textIntroduction: Undernutrition during early life causes chronic disease with specific impairments to the heart and skeletal muscle. Purpose: To determine the effects of early-life undernutrition on adult exercise capacity as a result of cardiac and skeletal muscle function. Methods: Pups were undernourished during gestation (GUN) or lactation (PUN) using a cross-fostering nutritive mouse model. At postnatal day 21 (PN21), all mice were weaned and refed a control diet. At PN67, mice performed a maximal treadmill test. Echocardiography and Doppler blood flow analysis was performed at PN72, following which skeletal muscle cross-sectional area (CSA) and fiber type were determined. Results: Maximal running capacity was reduced (Diet: P=0.0002) in GUN and PUN mice. Left ventricular mass (Diet: P=0.03) and posterior wall thickness during systole (Diet*Sex: P=0.03) of GUN and PUN mice was reduced, causing PUN mice to have reduced (Diet: P=0.04) stroke volume (SV). Heart Rate (HR) of GUN mice showed a trend (Diet: P=0.07) towards greater resting values than other groups. PUN mice had greater CSA of SOL fibers. PUN had a reduced (Diet: P=0.03) proportion of type-IIX fibers in the EDL and a greater (Diet: P=0.008) percentage of type-IIB fibers in the EDL. Conclusion: Gestational and Postnatal undernourishment impairs exercise capacity.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Getting to the Heart of the Planetary Health Movement: Nursing Research Through Collaborative Critical Autoethnography
Get PDFHumans and more-than-humans experience injustices related to the triple planetary crisis of climate change, pollution, and biodiversity loss. Nurses hold the power and shared Responsibility (Note on Capitalization: Indigenous Scholars resist colonial grammatical structures and recognize ancestral knowledge by capitalizing references to Indigenous Ways of Knowing (Respect, Relations, and Responsibilities are capitalized to acknowledge Indigenous Mi’kmaw Teachings of our collective Responsibilities to m’sit no’ko’maq (All our Relations). Respect for Land, Nature, Knowledge Keepers, Elders, and the names of Tribes, including the Salmon People and sacred spaces, such as the Longhouse, are also denoted with capitals)) to support the health and well-being of each other and Mother Earth. The heart of the Planetary Health movement to address these impacts centers on an understanding of humanity’s interconnection within Nature. As nurses, we seek partnerships with more-than-human communities to promote personal and collective wellness, Planetary Health, and multispecies justice. This article introduces a longitudinal, collaborative autoethnography of our initial engagement with more-than-human communities. In this research, we utilize reflexive photovoice and shared journals to describe our early conversation about this interconnection with three waterways across diverse geographies. This work acknowledges the importance of relational and embodied Ways of Knowing and Being. We invite nurses to embrace the heart of the Planetary Health movement and share these stories with their more-than-human community partners
A Real-World Comparison Between Adjuvant Docetaxel with Cyclophosphamide (TC) and Anthracycline–Taxane Chemotherapy in Early HER-2 Negative Breast Cancer
Get PDFBackground: Anthracycline–taxane chemotherapy is the gold standard in high-risk breast cancer (BC), despite the potential risk of congestive heart failure (CHF). A suitable alternative for anthracycline-sparing chemotherapy is through the combination of docetaxel and cyclophosphamide (TC). Methods: Through a retrospective study of stage I-III HER2-negative BC, using administrative databases, we analyzed a total of 10,634 women treated with adjuvant chemotherapy in Ontario, Canada, between 2009 and 2017. We compared TC versus standardized anthracycline–taxane chemotherapies (ACT and FEC-D). We investigated the overall survival (OS), and explored the incidence of CHF, emergency department (ED) visits and febrile neutropenia. Results: With a median follow-up of 5.5 years, the 5-year analysis showed an increased OS in patients treated with TC, versus those treated with ACT, HR 0.77 (0.63–0.95, p = 0.015). Among ER+ BC, there was an increased OS in patients treated with ACT and FEC-D, versus those treated with TC, HR 0.70 (0.52–0.95, p = 0.021) and HR 0.71 (0.56–0.91, p = 0.007), respectively. There were no substantial differences in CHF, between TC and anthracycline-based treatments. Patients treated with TC and FEC-D had more ED visits, compared to those treated with ACT. Conclusion: Our study shows that anthracycline–taxane regimens were the most commonly prescribed adjuvant chemotherapy options in HER2-negative BC. Women who received ACT had the lowest OS, likely due to their unfavorable pathology