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Bridging the Gap: An Immigrant Family Strengthening Workshop
No full textMaster of Social Work (MSW)Immigrant families benefit from a wide variety of resources to help in their transition to life in the United States. One area that needs to be more robustly addressed is assistance in preventing harmful intergenerational cultural conflict that can emerge as the children of immigrants grow up in a different cultural context than their parents. In prior research and qualitative interviews, intergenerational cultural conflict has been found to be harmful to family relationships and youth outcomes. While many parenting programs already exist, immigrant families need specialized resources and culturally relevant information beyond what typical American interventions offer. This proposed intervention consists of an 8-week adaptable workshop series for immigrant parents and their children ages 13-17, in order to learn the communication and emotional regulation skills needed to effectively navigate cultural differences and prevent intergenerational cultural conflict from emerging. Participating families will be split into parent and teen groups for 90 minutes to discuss a weekly topic, practice skills, and obtain social support from peers. The workshop is designed to help families determine their own solutions that are holistically informed by cultural knowledge, ideas from their peers, and the workshop curriculum. Participating families will be assessed on their relationship quality and use of communication skills
Antimicrobial Resistance in Children at Hospital Discharge in Western Kenya
No full textThesis (Ph.D.)--University of Washington, 2022Introduction: Antimicrobial resistance (AMR) is associated with millions of deaths per year worldwide. The global burden of AMR is disproportionately high in Sub-Saharan Africa, primarily as a result of the high incidence of infectious diseases. Children who have been hospitalized and subsequently discharged in this region are at high risk for morbidity and mortality. It is possible that AMR plays a role in these poor outcomes through treatment failure due to antibiotic resistant pathogens or through the acquisition of new resistant infections either during hospitalization or the post-discharge period. In addition, children carrying resistance determinants may serve as an important reservoir of AMR that can be transferred to other household and community members. Conditions favorable to the spread of bacteria, and therefore AMR, such as crowded living conditions, insufficient sanitation and hygiene facilities and contaminated water sources, may exacerbate community transmission from these children to others. Methods: This dissertation used bacterial isolates from fecal samples from a recently completed clinical trial examining whether azithromycin reduced death and rehospitalization during the discharge period in children aged 6 – 59 months in western Kenya. Fecal samples were collected at the time of enrollment, prior to the administration of the first dose of the study drug or placebo. Study staff performed medical record extractions, conducted interviews with caregivers, and study clinicians performed a medical examination. Fecal samples were also collected at follow-up visits 3-months and 6-months post-enrollment. Bacterial isolates, including Escherichia coli (E. coli), Salmonella, and Shigella were isolated and underwent antimicrobial susceptibility testing (AST). Additionally, a random subset of caregivers were enrolled and provided fecal samples for the isolation of E. coli and subsequent AST. The proportion of E. coli isolated from children at enrollment resistant to a panel of antibiotics and extended-spectrum beta-lactamase (ESBL) production and risk factors for carriage of ESBL-producing E. coli was determined (Chapter 1). Patterns of AMR in E. coli isolated from children and their caregivers at the time of hospital discharge were examined and correlates of concordance assessed (Chapter 2). Agreement of susceptibility to antibiotics in Salmonella or Shigella with E. coli isolated from the same fecal sample were also examined (Chapter 3). Results: The proportion of E. coli isolated from children resistant to ampicillin (95%), gentamicin (44%), ceftriaxone (46%), and the presence of ESBL (44%) was high. Use of antibiotics during the hospitalization (adjusted prevalence ration [aPR] = 2.23; 95% CI: 1.29 – 3.83) and being hospitalized within the prior year (aPR = 1.32 [1.07 – 1.69]) were associated with the presence of ESBL producing E. coli. Additionally, being female (aPR = 1.42; 95% CI: 1.15 – 1.76), practicing open defecation (aPR = 2.02; 95% CI: 1.39 – 2.94), and having a toilet shared with other households (aPR = 1.49; 95% CI: 1.17 – 1.89) were also associated with carriage of ESBL E. coli. Across all antibiotics tested, caregivers had less AMR than children. Concordance of AMR was more common when resistance to a particular antibiotic was particularly high (cefoxitin, chloramphenicol, and cotrimoxazole) or low (imipenem). ESBL concordance was less common in child-caregiver pairs where there was more than one child in the household compared to those without additional children (55.0% vs. 79.9% [p = 0.02]) and with caregivers who reported being employed or a student than those who were not employed or a student (45.0% vs. 55.0%) [p = 0.05]). E. coli had high concordance for susceptibility and was a reliable predictor of the outcome to cephalosporins and gentamicin but was a poor predictor of susceptibility to azithromycin and ciprofloxacin. Conclusion: Children who have been discharged from hospital have a high burden of AMR, which may contribute to poor outcomes in the post-discharge period. Given the frequency of AMR in this high risk population, new guidelines for the treatment of common infectious syndromes in children with a recent hospitalization should be considered. Additionally, because these children are likely to carry AMR from the hospital back into the community, they may pass AMR to family and other community members. Interventions which reduce the transmission of infectious agents may also reduce the transmission of AMR
Implementing an Integrate-and-Fire Neural Network on a Bidirectional Brain-Computer Interface
No full textThesis (Ph.D.)--University of Washington, 2022There is a growing interest in using intracortical microstimulation (ICMS) as a means of neurorehabilitation, from using it to rewire synaptic connections in the brain, to providing a means of providing artificial sensations to provide feedback to patients controlling external devices such as robotic limbs via decoded neural activity. Towards the goal of neurorehabilitation, there have been recent efforts to integrate artificial neural networks (ANNs) with the brain and train them to manipulate neuronal activity in a context-specific manner with the goal of developing brain-computer interfaces (BCIs) that can restore function to damaged neural circuitry. In this thesis, I present my work whose aim was to interface artificial spiking neurons with biological neurons in primary motor cortex to create hybrid biological/artificial neural networks that altered the firing dynamics of the biological neurons. In these hybrid networks, spikes that are detected from the biological neurons send artificial postsynaptic potentials (PSPs) to the artificial neurons, whose magnitudes and polarities are defined by weights that characterize the strengths of their connections. When the membrane potentials of the artificial neurons exceed a predetermined threshold, they spike, and subsequently trigger ICMS to manipulate the activity of the biological neurons. We first characterize the effects of ICMS on neural activity in primary motor cortex (M1) of pigtail macaques, and show how it elicits a brief excitatory response followed by a longer inhibitory response. We then show how the probability of evoking single action potentials has at least three dependences – the stimulation amplitude, time delay between the neuron’s previous spike and stimulation onset, and its firing rate. Finally, we show how repetitive stimulation can increase or decrease the probability over time, likely due to mechanisms of short-term plasticity.
I used these results to explore how various properties of the hybrid biological/artificial neural networks shape the closed-loop dynamics between the biological and artificial neurons. To do so, I measure changes in the auto-, and cross-correlograms of the biological neurons between their spontaneous and closed-loop dynamics, and show how features within the correlograms are related to the size, connectivity, number of hidden layers, magnitude of inhibition, and stimulation delays of the network.
I then show how the closed-loop dynamics can be simulated by recording the spontaneous activity as well as the open-loop responses of the biological neurons to ICMS, and use the model to further characterize how the features of the hybrid network influence the closed-loop dynamics free from experimental constraints such as the non-stationarity of the firing rates and evoked spike probabilities of the biological neurons over time. I also use the model to explore how stimulation artifacts impacted the closed-loop operation of the hybrid neural network by obstructing the detection of spikes. To do so, I characterize the number of obstructed spikes as a function of both the network size and connection strength between the biological and artificial neurons. I found that compared to the size of the network, the strength of the connections between the biological and artificial neurons was the greater determinant of how many spikes were blanked.
Lastly, I discuss preliminary work of the development of a computational model whose goal is to demonstrate that ANNs can be interfaced with the brain to restore lost motor function. I first train a small recurrent ANN, which simulates a motor circuit within the brain, to perform a 1D motor task with a reinforcement learning algorithm. I then lesion the network by deleting a subset of the neurons and their related connections, and show how even with retraining, the network is incapable of relearning the task. Finally, I discuss future steps in which a second ANN, whose outputs use ICMS to activate neurons within the original ANN, can be used to restore network function and task performance
A source study of two ballets and a divertissement by Marius Petipa
No full textThesis (Ph.D.)--University of Washington, 2022The ballets of Marius Petipa (1818–1910) account for most of the nineteenth-century ballets that constitute the current global classical repertory. In this dissertation, I use a selection of sources to provide detailed descriptions of the music, choreography, pantomime, and action in early productions of two of Petipa’s original ballets, La Bayadère (1877, revived 1900) and Raymonda (1898), and the divertissement Le jardin animé from the ballet Le Corsaire (staged by Petipa in 1868, 1880, and 1899), all of which are part of this canon. These ballets today are usually presented in versions that have been handed down from artist to artist via oral transmission, the time-honored method of passing traditional work from one generation to the next. But because such productions inevitably bear the accumulated accretions and deletions from a century of changes in taste, technique, and aesthetics, much of the choreography, mime, and action created and staged by Petipa has been lost. Fortunately, sources survive that reveal much about Petipa’s stagings of these ballets. Among them are such documents as the choreographer’s preparatory notes, instructions for composers, musical and choreographic scores, and mime scripts. These performance-related sources also offer insight into Petipa’s creative process and reveal features that distinguish his work. Such features include his incorporation of Italian ballet technique into his French-based choreographic step vocabulary and his inclusion of a new type of narrative-based, multi-movement dance suite for which Petipa appropriated the old term pas d’action. In addition to scene-by-scene descriptions, I offer a detailed introduction to the Stepanov choreographic notation system used to document Petipa’s choreography, discussion of the genesis and broader context of the ballets, plot summaries, character sketches, music analysis, performance histories, and detailed descriptions of sources. I also contextualize certain elements of these ballets within Petipa’s output, and I discuss several Western productions of La Bayadère and Raymonda that were staged in the early and mid-twentieth century either using some of these sources or retaining features found in them. Ultimately, a much clearer picture emerges than what has heretofore been known of these ballets in their earliest incarnations
Energetics of Small Molecules and Molecular Fragments on Model Catalyst Surfaces: Adsorption Calorimetry on Pt(111) and Cu(111)
No full textThesis (Ph.D.)--University of Washington, 2022Heterogeneous catalysis is essential for the development and support of modern society, with the vast majority of chemical production processes reliant on catalysts. New catalysts and catalytic reactions constitute promising pathways forward in combatting the effects of climate change and transitioning human society off of our reliance on fossil fuels. However, there is an absence of a complete fundamental understanding of observed differences and trends in catalytic behavior that impedes the rapid, strategic development of new catalytic processes. Computational modeling methods, such as Density Functional Theory (DFT), constitute powerful tools for the rapid screening of catalyst materials, but these methods have large errors in energy accuracy which severely limit their quantitative predictive abilities. These methods are dependent on experimentally determined benchmarks to guide modifications for improving their energy accuracy. The technique of single crystal adsorption calorimetry (SCAC) is uniquely able to study the energetics of irreversible adsorption processes on well-defined surface sites. SCAC can therefore provide these key benchmarks and fundamental understandings of the energetics of molecular and dissociative adsorption into molecular fragments and other key surface reaction intermediates commonly seen in industrial catalytic applications.
This dissertation presents experimental SCAC results for the study of the energetics of adsorption of small molecules and molecular fragments on model catalyst surfaces, namely Pt(111) and Cu(111). This work builds upon previous efforts from the Campbell group to develop a systematic understanding of trends and observed differences in catalytic behavior on late-transition metal catalysts. Additionally, by employing models recently developed by this group, we are able to estimate the adhesion energies of liquid solvents to clean, single-crystal metal surfaces from the experimental calorimetry results. This allows for the estimation of the effects of each solvent on the energetics of adsorption and desorption for surface reactants and intermediates of interest.
The study of the energetics of acetonitrile and n¬-decane adsorption on Pt(111), two solvents of particular interest, are reported here. Acetonitrile an important solvent due to its unique, desirable properties which make it of particular interest for electrochemical applications and the engineering of mixed solvent environments. n-Decane is similarly of interest in catalysis as linear alkanes of that and similar size are commonly used as solvents in catalytic reactions over Pt-group metals. From the experimentally determined heat of adsorption versus coverage we estimate adhesion energies of these liquid solvents to the Pt(111) surface to be Eadh = 0.198 J/m2 for acetonitrile and Eadh = 0.148 J/m2 for n-decane. Additionally, the adhesion energy of liquid formic acid to Cu(111) is estimated to be Eadh = 0.271 J/m2. These values can be used to quantify the solvent effects of these species on the local surface reaction environment.
The calorimetrically measured heats of adsorption versus coverage are reported here for acetonitrile on Pt(111) at 100 K and 180 K, n-¬decane adsorption on Pt(111) at 150 K, azulene adsorption on Pt(111) at 150 K, and for both the molecular and dissociative adsorption of formic acid on clean and oxygen-precovered Cu(111). In combination with previously reported experimental results and DFT simulations of these systems, a number of important fundamental insights are drawn. The analysis of the n-decane heats of adsorption in comparison to a previous TPD study of shorter linear alkanes extends the observed trends to larger species such as n-decane that desorb irreversibly. Namely, we report that the adsorption energy increases nearly proportionally to carbon number, and the adhesion energy remains nearly constant (for a given surface).
Naphthalene and azulene are of particular interest as representative molecules for the regular structure of graphene and the most common defect found in graphene sheets, respectively. Therefore the study of their adsorption energetics can inform experimental and computational systems involving graphene more broadly. Comparison of the heats of adsorption for azulene on Pt(111) first presented here with previous results for naphthalene and DFT simulations of both show that azulene binds significantly stronger to Pt(111) (by ~100 kJ/mol) than its isomer naphthalene. We show that DFT accurately predicts the adsorption energy of azulene but overestimates the binding energy of naphthalene, indicating that DFT is not accurately modeling the energy differences between these two systems.
We report here the dissociative adsorption of formic acid on oxygen-precovered Cu(111), which results in the formation of adsorbed bidentate formate and gaseous water at 240 K. Formic acid and formate are common intermediates in a variety of reactions on late transition metals, ranging from well-established industrial reactions to emergent clean energy technologies. From the heats of this dissociative adsorption reaction, we extract a bond enthalpy of bidentate formate to Cu(111) of 335 kJ/mol, and an enthalpy of formation of bidentate formate on Cu(111) of -465 kJ/mol. We show that these enthalpies are slightly greater than those on Ni(111) (by ~15 kJ/mol) and significantly greater than those on Pt(111) (by ~85 kJ/mol). This is in opposition to the predicted order of bond strength from DFT, where Ni is predicted to bind formate more strongly than Cu, and indicates that DFT is not accurately modeling this trend in adsorption between these three surfaces. This study also constitutes the first experimental measurement of the energetics of any adsorbed molecular fragment on any Cu surface. In comparison to previous results on Pt(111) and Ni(111) this allows for the direct comparison of a single molecular fragment on all three surfaces for the first time. This forms a suite of key experimental benchmarks for improving the energy accuracy of computational models like DFT, as well as crucial fundamental insights into trends and observed differences in catalysis on late-transition metal surfaces.
Lastly, we report a detailed kinetics study of the aqueous-phase hydrogenation of phenol and benzaldehyde on Pt, Pd, and Rh using small-scale thermal and electrocatalytic reactors. These molecules represent common intermediates in the process of breaking down biomass and converting its constituents into biofuels and other value-added chemicals. This work shows that the observed catalytic behavior is well fit by a Langmuir-Hinshelwood mechanism with competitive adsorption (organic versus hydrogen adsorption) on terrace, or (111)-like, sites. Additionally, we report that adsorbed benzaldehyde inhibits the formation of a bulk Pd-hydride whereas phenol does not, explaining the extreme differences in observed catalytic activity between these two systems. This work informs efforts to correlate molecular structure of biomass intermediates of interest with catalytic activity on late-transition metal catalysts
At War Again: Soldiers, Civilians, and Multi-War Experiences in the British Empire, 1885-1918
No full textThesis (Ph.D.)--University of Washington, 2022In the decades on either side of the turn of the twentieth century, Britain was at war in its empire. At War Again: Soldiers, Civilians, and Multi-War Experiences in the British Empire, 1885-1918 is the first academic history of a diverse group of Britons who took part in multiple British imperial conflicts, from so-called expeditions, campaigns, rebellions, and wars that took place throughout Africa and in other British colonies, to the First World War. Multi-war veterans belonged to a particular cohort that came of age in the waning years of the nineteenth century and who were often in their late thirties, forties, or fifties when they experienced World War I. They were working-class soldiers, career military officers, nurses, caregivers, and family members of those who served. Together, the diversity of their experiences shows that the particular character of the British empire at the turn of the century meant that it was not only possible, but common, to live a life repeatedly punctuated by experiences of war. This project recasts the relationship between colonial violence and military history by studying the lives and experiences of those Britons for whom the First World War did not come first. Their lives not only allow for a re-consideration of the relationship between the First World War and earlier British imperial wars, but also demonstrate the centrality of war and violence to the maintenance and expansion of European empires, particularly in Africa. Using critical approaches to biographical writing and analysis, including group biography and approaches to the biographies of material culture objects, this project argues for the importance of continuities that extend beyond traditional chronological and geographic lines. Starting first from the experiences of individuals whose lives unite nineteenth-century colonial wars to the First World War, it then analogizes out to consider bigger picture connections across systems of empire, nation, and war. It also shows that as British multi-war veterans made meaning of their repeated military service and their participation in programs of colonial violence, they also came to understand themselves as Britons. This project, then, makes an argument for the importance of subjective experience and identity formation as essential for understanding the connections between colonial conflict and the First World War
Diversity, Temporality, Population: The Securitization of the Democratic Pastorate and the Rise of the Racial Liberal Security State
No full textThesis (Ph.D.)--University of Washington, 2022Reading across the domains of disciplinary knowledge formations, public educational initiatives, governmental documentation, and social movement discourses, this dissertation examines emergent meanings of security as the antiracist renovation of the liberal tradition conjoins with questions of social and national security during the U.S. “encounter with totalitarianism” in the years leading up to WWII. In the development of the ethnicity paradigm in the social sciences, the principles of neutrality that governed the administration of New Deal state programming, and the advent and proliferation of public and private educational initiatives to promote cultural pluralism, this dissertation identifies and traces a series of interrelated and co-constitutive “racial security logics” that create new parameters of intelligibility (and governance) for subjects of and for a purportedly antiracist state. The purportedly antiracist state form that liberal progressive narratives claim is achieved later during what Michael Omi and Howard Winant have famously referred to as “the period of the racial break,” is a state form that is simultaneously imagined as “achieved” and perpetually “coming into being” in the postwar period. This dissertation locates and names the material and epistemic preconditions for this shift in the immediate prewar period. Central to this new state form coming into being, I argue, was the production of a progressive telos for the nation that both constructed racial liberals as a “democratic pastorate” and conducted them as mangers of the general population to work toward the “common good” of a progressive, inclusive future secured through the monitoring, surveillance, and policing of the disorganizing potentialities of race. Through the securitization of the democratic pastorate, a new form of state rationality developed that could secure both a still thoroughly racialized stratified population, as well new material relations for the racial state, while simultaneously disavowing those relations of violence through the rise of race relations knowledge industries. At its core, this dissertation examines how the U.S. racial liberal state state extended and transformed its modes of racial violence precisely through purportedly antiracist progressive social, political, and intellectual movements that understood liberal progress as the achievement of cultural identity through the universalizing rubrics of procedural neutrality and inclusive diversity
Saling-Pusa Tayo [We Are Saling-Pusa]: Toward Being and Teaching Filipinxs on Indigenous Lands
No full textThesis (Ph.D.)--University of Washington, 2022Filipinxs in the United States/Turtle Island are both racialized “others” and settlers on Indigenous lands. This study asks the two following questions: What does it mean to be Filipinx on Indigenous Lands? How do Filipinxs navigate the world? My co-researchers and I employed a Projects in Humanization, relational approach to exploring these questions within and beyond multiple Filipinx-themed undergraduate seminars I facilitated between 2017 and 2021. Our focus for the first question was elucidating Filipinxness in terms of group identifications (e.g., Filipinx, brown, Catholic). Our focus for the second question involved highlighting actions and commitments that we related to Filipinxness. I employed a constructivist, grounded theory approach to develop a theory of the saling-pusa, or “informal member,” as both ontological and pedagogical tool that involves refusal and desire. I propose that Filipinxs as saling-pusa on Indigenous lands lean into liminality as a strength and a place of radical possibilities toward being ourselves, teaching within and outside our communities, and solidarities with Indigenous peoples and other groups marginalized by systemic injustices
3D microscopic imaging with computational image analysis to improve cancer assessment
No full textThesis (Ph.D.)--University of Washington, 2022Non-destructive, slide-free, and comprehensive pathology of clinical specimens can improve clinical workflow efficiency and diagnostic performance. Recent advances in optical-sectioning microscopy and optical clearing techniques enable volumetric imaging of thick tissue specimens with subcellular resolution. In addition, computational analysis of 3D microscopic image datasets can objectively assist human observers with more efficient and accurate pathological analysis. In this dissertation, we explore two emerging optical-sectioning microscopy techniques, microscopy with ultraviolet surface excitation (MUSE) and open-top light-sheet (OTLS) microscopy, along with various computational methods to enhance, synthesize or analyze the 3D pathological images of tissue specimen, to improve clinical assessment of breast cancer and prostate cancer. For accurate intraoperative lumpectomy margin assessment, we present a fully automated MUSE system that incorporates 3D deconvolution along with a fluorescent analogue of histology stain, facilitating comprehensive pathology of fresh breast specimen surfaces. For rapid diagnosis of prostate cancer, we developed a compact workflow (1Hr2Dx), consisting of fluorescence labeling, tissue clearing, and 3D OTLS microscopy, to diagnose a set of 12 prostate needle cores within an hour of receipt, which can provide patients with a preliminary on-site diagnosis after a biopsy procedure, thereby alleviating anxiety and potentially expediting treatments. To facilitate more reliable cancer risk evaluation, we developed a workflow for non-destructive 3D pathology and computational analysis of whole prostate biopsies that are labeled with a fluorescent analog of H&E staining. The analysis is based upon the development of an annotation-free deep-learning-based volumetric segmentation strategy, namely image-translation-assisted segmentation in 3D (ITAS3D). Based on the glandular features extracted from our 3D gland segmentations, we show that 3D glandular features are superior to 2D features for risk stratification based on patient outcomes
Interaction-driven dynamical delocalization in a kicked one-dimensional ultracold gas
No full textThesis (Ph.D.)--University of Washington, 2022This dissertation reports on the experimental observation of interaction-driven dynamical delocalization in a kicked one-dimensional ultracold gas. In the absence of interactions, particles in a one-dimensional disordered medium are localized due to quantum interference as predicted by the Anderson model. The evolution of this well-known localization phenomenon in the presence of interactions has been the subject of intense scrutiny in the past decades, including conflicting theoretical predictions in some cases. Using the quantum kicked rotor (QKR), we engineered the Anderson model in the synthetic momentum space where the equivalent localization phenomenon is termed dynamical localization. However, interaction effects had not been observed in earlier experimental observations of dynamical localization. We detail the implementation of a three-dimensional optical lattice that is used to control the interactions in the system and to realize the QKR Hamiltonian. Using ultracold gases in 1D tubes, we perform a quantum simulation of the QKR Hamiltonian in the presence of interactions and find that interactions destroy the localization and lead to slower-than-linear energy growth or sub-diffusive dynamics. The measured sub-diffusive exponents are not universal or monotonically varying with the various experimental parameters. However, we find that the onset time of delocalization is always shorter with stronger interaction or kick strengths. By temporally modulating the kick strength with incommensurate frequencies, we also engineered higher dimensional Anderson models and observed similar interaction-driven delocalization phenomena. The metal-insulator Anderson transition in the presence of interactions is also studied in the 3D case with varying kick strength. Our results shed light on interaction-driven transport, in a regime where theoretical approaches are extremely challenging and predict drastically different dynamics