Bioculture Journal
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Protons and zinc ions intercalation in aqueous MnVO zinc-ion batteries
No full textThesis (Master's)--University of Washington, 2022Vanadium oxide has been regarded as one of the most promising cathode materials for aqueous zinc ions batteries (ZIBS). However, the mechanisms of ion intercalations are still hotly debated. Traditional structural and elemental characterization methods are mostly used as indirect evidence to characterize the co-intercalation of hydrogen and zinc ions. To find direct evidence for the intercalation of protons and zinc ions, this paper, using MnVO as the cathode material, demonstrated that the intercalation process produces the appearance of Zinc hydroxide sulfate (ZHS, an alkaline zinc salt) and soluble hydroxides associated with the electrolyte on the electrolyte surface
Low-Resource Neural Adaptation: A Unified Data Adaptation Framework for Neural Networks
No full textThesis (Ph.D.)--University of Washington, 2022Many machine learning (ML) models are trained on specific datasets for specific tasks. While traditional transfer learning can adapt to new datasets when labeled data are adequate, adapting to small datasets is still a challenging task. Researchers have applied multi-task learning, meta-learning, weakly-supervised learning, self-supervision, generative adversarial training, and active learning for various data adaptation applications. However, a unified data adaptation framework has yet to be developed. This study proposes a unified framework that can adapt to small datasets in a dynamic environment. Our framework, with a versatile encoder and various decoders, can simultaneously learn from source datasets and estimate confidence for novel data samples. We apply the framework to real-world medical imaging, affective computing, eye-tracking analysis, and database management applications
Trapping and cooling two-dimensional crystals of barium ions
No full textThesis (Ph.D.)--University of Washington, 2022The design and characterization of a trap specifically designed to create 2D crystals of trappedbarium ions is presented. The trap is used to study the Doppler cooling of 2D crystals.
Ions in RF traps are subject to micromotion, a time-dependent driven motion caused by the
RF fields themselves. This micromotion leads to Doppler shifts in laser-ion interactions. Laser
cooling of 2D crystals can become increasingly difficult as crystals get bigger and are therefore
subjected to more micromotion. We explore two methods for Doppler cooling in the presence of
significant micromotion. The first method is to power broaden and detune cooling beams, reducing
the distortions on atomic lineshape due to micromotion. The second method is to use nanosecond
pulses of laser light synchronized with the trap RF in order to selectively cool the ions over a
narrow range of velocities
Contraceptive Education for Active-Duty Service Members: An evaluation using the RE-AIM framework
No full textThesis (Master's)--University of Washington, 2022Background: Nearly two-thirds of military pregnancies are unintended, with 5.5% of military women experiencing unintended pregnancy in 2015. Education-based interventions are effective at improving contraceptive knowledge as well as contraceptive behaviors among military populations. However, traditional education-based interventions often require multiple hours or days of staff and participants’ time. Additionally, little is known about baseline contraceptive knowledge of Army service members. We assessed the impact of a one-hour contraceptive education course embedded within a same-day contraceptive clinic.Methods: Participants were recruited from a convenience sample of active-duty service members presenting for a scheduled bi-weekly contraceptive clinic. All service-members participating in the contraceptive clinic were offered the opportunity to participate in the contraceptive education course. Education course participants were asked to complete a pre and post intervention questionnaire. Pre and post course questionnaires included a validated 25-question contraceptive knowledge assessment and asked about preferred contraceptive method. The post-course survey included an additional validated 16-question contraceptive decision conflict scale. A control group consisted of active-duty Army women presenting for routine appointments to the same primary care clinic who did not complete the education course. The control group participants were asked to complete pre and post appointment questionnaires for contraceptive knowledge, preference, and decision conflict. Implementation of the contraceptive clinic and education course was qualitatively assessed using the RE-AIM evaluation model as described by Glasgow et al.
Findings: Fourteen contraceptive class participants and ten control participants enrolled in the study and completed baseline surveys. Baseline contraceptive knowledge was similar between groups, with mean aggregate score of 13.58 out of a possible 25. The questions most frequently missed pertained to proper use of contraceptive methods, method side effects, and medical contraindications. Follow-up surveys were only completed by 4% of total study participants. As a result, change in contraceptive knowledge and preferred contraceptive method could not be assessed. In qualitative program evaluation, several threats to program adoption were identified at the provider and clinic level.
Discussion: This study was unable to assess the primary outcome of change in contraceptive knowledge or preferred contraceptive method. However, it provides valuable information about specific contraceptive knowledge deficits among Army women. This information can be used to design future education interventions. Additional studies are needed to assess the impact of this contraceptive education program on contraceptive knowledge retention, contraceptive behaviors, and pregnancy
iOBPdb – A Database for Experimentally Determined Functional Characterization of Odorant Binding Proteins
No full textOdorant binding proteins (OBPs) are extra-cellular proteins which solubilize and transport volatile organic compounds (VOCs). Thousands of OBPs have been identified through genome sequencing and hundreds have been characterized by fluorescence ligand binding assays in individual studies. There is a limited understanding of the comparative structure-function relations of OBPs, primarily due to a lack of a centralized database that relates OBP binding affinity and structure. Combining 215 functional studies containing 381 unique OBPs from 91 insect species we present a database, iOBPdb: https://iobpdb.herokuapp.com, of OBP binding affinities for 620 unique VOC targets. This initial database provides powerful search and associative capabilities for retrieving and analyzing OBP-VOC binding interaction data. We present our results in a variety of phylogenetic representations as well as providing the binding profiles of OBP groups to VOC functional moieties. Potential applications include development of molecular probes for biosensors, novel bioassays and drugs, targeted pesticides which inhibit VOC / OBP interactions, and understanding odor sensing and perception in the brain.Partial funding was received from WE-REACH program at the University of Washington through the RADx RAD program at NIDCR/NIH
Supporting a Diversely Connected World via Community Cellular Networking
No full textThesis (Ph.D.)--University of Washington, 2022Community cellular networks (CCNs), small-scale cellular networks owned and operated by members of the communities they serve, have the potential to provide sustainable wide-area coverage across a diverse range of contexts on the margins of the Internet. This dissertation first characterizes some of the operational challenges observed in an existing CCN, and then develops new designs for future community cellular systems to address the identified challenges.To ground the research, I gather a unique dataset characterizing the operation of a remote, expensive, data-only community LTE network. Through tight integration with the operator's infrastructure, the dataset has visibility to drill down to individual user behaviors in terms of both network traffic and prepaid credit purchases and transfers. I find that despite the network's constrained capacity, use is still highly unbalanced, with a handful of heavy consumers providing an outsized portion of network revenue. A large portion of the userbase only has intermittent access in this model. 45% of users are offline more days than online, and the median user consumes only 77 MB per day online and 36 MB per day on average, limiting consumption by frequently "topping up" in small amounts. The network is also only somewhat reliable, with downtime caused by software failures, network failures, and the generally harsh conditions on the rural edge.
To address the reliability challenge, I observe that multiple hotspot providers were already operating in the area, and propose a new authentication architecture to allow fallback to an overlapping provider even when the user's home network is offline. This system, dAuth, is fully backwards compatible with standard off-the-shelf devices, making it feasible for immediate deployment. I design, prototype, and evaluate dAuth against existing private edge-core and cloud-core architectures, and find it comparable to the status quo while providing robust operation in the presence of failures and good scaling properties as the number of small operators increases.
To address the challenge of providing sustainable access while avoiding intermittent availability for low-income users, I explore the design of community-based congestion-management policies and network management mechanisms through the lens of network capacity as a common pool resource. I present qualitative insights from a series of workshops and interviews exploring designs for community-scale networks with resource sharing. Participants expressed conflicting desires for preserving individual privacy while collecting longitudinal data to track the network's impact on the community, prioritization of high-value applications, equal link allocation between users, and human-mediated congestion management in lieu of automated enforcement.
Overall my work provides new directions for the design of next-generation community cellular networks that can be more reliable and operate with a wider range of governance structures to sustainably serve a wider range of communities
Impacts of COVID-19 on rural Latinx families and implications for policy
No full textThesis (Master's)--University of Washington, 2022The COVID-19 pandemic has disproportionately impacted rural communities. While school closures helped slow the spread of transmission, this has exacerbated existing learning gaps for students in rural communities. A qualitative research study was conducted to understand the impact of the COVID-19 pandemic on social and academic disruptions as well as mental health of Latinx families. Four parent focus groups were conducted, and 18 semi-structured interviews with their children. Data collection took place from April to August of 2021. Five major themes emerged including 1) social disruptions, 2) family disruptions, 3) academic disruptions, 4) children’s mental health, and 5) concerns about returning to onsite learning. The findings from this study can inform development of programs and public policies to mitigate the challenges experienced by rural Latinx families during the pandemic
Stimuli-responsive DNA-based hydrogels for controlled drug delivery applications
No full textAdverse side effects from drugs being delivered to healthy tissue inside the body remain a persistent challenge within the medical field. Targeted drug delivery by use of stimuli-responsive DNA-based hydrogels emerge as a promising solution to this issue. These hydrogels can be used for a “smart” controlled drug delivery system that enables a drug to be delivered to a target location in a controlled amount by responding to an external stimulus. DNA hydrogels that respond to various non-biological and biological stimuli and their potential applications for targeted drug delivery are discussed in this paper
Extracting and Inferring Personal Attributes from Dialogue
No full textThesis (Master's)--University of Washington, 2021Personal attributes represent structured information about a person, such as their hobbies, pets, family, likes and dislikes. In this work, we introduce the tasks of extracting and inferring personal attributes from human-human dialogue. We first demonstrate the benefit of incorporating personal attributes in a social chit-chat dialogue model and task-oriented dialogue setting. Thus motivated, we propose the tasks of personal attribute extraction and inference, and then analyze the linguistic demands of these tasks. To meet these challenges, we introduce a simple and extensible model that combines an autoregressive language model utilizing constrained attribute generation with a discriminative reranker. Our model outperforms strong baselines on extracting personal attributes as well as inferring personal attributes that are not contained verbatim in utterances and instead requires commonsense reasoning and lexical inferences, which occur frequently in everyday conversation
Tectonics as recorded by thermochronometry, deformed datums, and submarine landscapes in western North America
No full textThesis (Ph.D.)--University of Washington, 2021Since the Mesozoic, the west coast of North America has experienced near continuous right-lateral shear. Over this time, a series of exotic crustal terranes accreted to and translated along the expanding westward edge of the continent. In this dissertation, I use low-temperature thermochronomtery, geologic map interpretation, geophysics, and geomorphic analysis, to explore the effects of this tectonic regime on deformation and landscape development. First, I determine the geologic history of the Wallowa and Bald Mountain Batholiths of Northeast Oregon to better understand whether the mountains they underlie formed in response to Miocene lithospheric delamination. I find that both batholiths were exhumed to the near surface during early to mid-Cretaceous terrane amalgamation and accretion. Multiple subsequent phases of localized uplift in the Cenozoic led to the mountainous landscape seen today. Building on this research, I use the distribution of the Miocene Columbia River Flood Basalt, in conjunction with crustal thickness estimates, to investigate the crustal structure responsible for Miocene to present strain partitioning in the Pacific Northwest, USA. From this analysis, I find that CRB deformation is correlated with crustal thickness, with less deformed regions having thinner crust. Turning to the north, I use low-temperature thermochronometry to estimate the timing of exhumation of the island archipelago Haida Gwaii. I determine that exhumation began with the passage of the Yakutat terrane, not as a result of transpression-induced subduction initiation as hypothesized in previous studies. Finally, I analyze the morphology of the seafloor along the Queen Charlotte Fault for the impact of tectonics. I find that transpression between the Pacific and North American plates determine the morphology of continental slope channel networks and whether the continental shelf is actively accumulating sediment. Across each of these studies, there is a common conclusion that the landscapes we observe today record multistage geologic histories