http://www.rssboard.org/rss-specification 720 https://escholarship.org/uc/ucd_etd/rss Recent eScholarship items from UC Davis Electronic Theses and Dissertations Fri, 15 May 2026 09:04:26 +0000 https://escholarship.org/uc/item/9dx182hw Members of Botryosphaeriaceae, Diatrypaceae, Togniniaceae, and Didymosphaeriaceae are known to cause wood canker and dieback diseases on various hosts around the world. Pruning wounds are major infection courts for these pathogens and remain susceptible for weeks. Samples showing branch canker and dieback symptoms on pear (Pyrus communis) trees were collected in 2022 and 2023 from the three main pear-producing counties in Northern California, Lake, Mendocino, and Sacramento, respectively, to identify the main pathogens causing branch canker and dieback disease on pears and evaluate registered synthetic and biological fungicides as pruning wound protectants to reduce primary infection. In this study, eight fungal species were isolated from symptomatic branch samples and identified with morphological characteristics coupled with multigene sequence analysis and phylogenetic comparison using the rDNA internal transcribed spacer (ITS), partial regions of beta-tubulin (tub2), elongation... https://escholarship.org/uc/item/9dx182hw Tue, 5 May 2026 00:00:00 +0000 Gonzalez Chavez, Celeste https://escholarship.org/uc/item/91g8q215 The rapid growth of data-intensive workloads in artificial intelligence, machine learning, and high-performance computing has placed unprecedented pressure on modern memory systems. While emerging memory technologies such as high-bandwidth DRAM, heterogeneous memory hierarchies, and coherent interconnects offer increased capacity and integration, they also exacerbate data movement amplification that limits performance, energy efficiency, and scalability. In post-Moore computing systems, reducing unnecessary data and metadata movement has become a primary architectural challenge.This dissertation investigates data movement inefficiencies in emerging memory systems, with a focus on DRAM caches and large-scale coherent shared memory architectures. First, it introduces a cycle-level, open-source DRAM cache model integrated into the gem5 full-system simulator. This model enables reproducible full-system evaluation of DRAM cache microarchitectural behavior, including metadata handling,... https://escholarship.org/uc/item/91g8q215 Tue, 5 May 2026 00:00:00 +0000 Babaie, Maryam https://escholarship.org/uc/item/8c76z5cb Two of the most important pests for California lettuce growers are western flower thrips (Frankliniella occidentalis) and aphids, specifically lettuce-currant aphid (Nasonovia ribisnigri). Western flower thrips vectors a pathogen, impatiens necrotic spot virus (INSV) which causes the death of infected lettuce plants. Lettuce-currant aphid is an invasive organism that can infest all lettuce varieties but is especially problematic in lettuce varieties that form closed heads, allowing the insect to proliferate undisturbed in the inner leaves. The primary means of control for both are insecticidal sprays, but over-reliance on those tools may reduce their effectiveness, and a changing regulatory landscape could impact their use in the region. Advances in spray and drone technology offer ways to improve insecticide applications and incorporate non-chemical alternatives into aphid and thrips management programs in this system. Automated precision sprayers use photodetection and... https://escholarship.org/uc/item/8c76z5cb Tue, 5 May 2026 00:00:00 +0000 Abrams, Adelaine Eve https://escholarship.org/uc/item/81f5w3zs Online tracking links user activity across time and contexts to persistent identities or profiles. While tracking can enable benign goals such as analytics and personalization, it also underpins targeted advertising and profiling that users often cannot easily observe or control. The tracking landscape is increasingly complex: browsers expose high-dimensional signals through evolving web APIs that support stateless identification via fingerprinting; third-party scripts embedded in first-party pages frequently execute with access to first-party state; and tracking signals are no longer limited to web interactions but can incorporate data collected from users’ environments through connected devices, where downstream use is difficult to audit.This thesis advances transparency and control over modern tracking through a coupled strategy that combines measurement and auditing with deployable mitigation. First, it introduces FP-Radar, a longitudinal measurement and learning framework... https://escholarship.org/uc/item/81f5w3zs Tue, 5 May 2026 00:00:00 +0000 Nikkhah Bahrami, Pouneh https://escholarship.org/uc/item/7xg66947 Rising housing costs and persistent inequities have made student housing affordability a critical concern in higher education, yet little is known about how university administrators conceptualize and act on this issue. Grounded in critical bifocality and shared equity leadership, this qualitative study draws on in-depth interviews with nineteen administrators at UC Davis to examine how they define affordability, how their proximity to students shapes those definitions, and how they make meaning of housing equity for marginalized student groups. Findings show a clear divergence in conceptualizations of affordability. Executive leaders and finance professionals often frame affordability through the lenses of compliance, financial sustainability, and risk management, while staff with closer proximity to students emphasize the gap between official budgets and students’ actual ability to secure stable housing. Low income and first generation students were most frequently identified... https://escholarship.org/uc/item/7xg66947 Tue, 5 May 2026 00:00:00 +0000 Doolittle, Em Camden https://escholarship.org/uc/item/7wd3n0nx The web has become an essential part of modern life, yet pervasive tracking increasingly threatens user privacy at scale. As traditional tracking mechanisms face growing regulatory and technical restrictions, advertisers and trackers continuously develop new techniques to circumvent protections. This dissertation presents a comprehensive approach to safeguarding user privacy in this evolving web tracking ecosystem across three themes: machine learning approaches to privacy protection, techno-legal analyses of web privacy, and preserving the integrity of the web ecosystem. The first part develops machine learning-based tools to detect and mitigate emerging tracking techniques. CookieGraph addresses the shift toward first-party tracking cookies using graph-based learning to identify tracking cookies with 93% accuracy, while reducing website breakage compared to blanket cookie blocking. PURL tackles link decoration abuse by safely sanitizing tracking information embedded in... https://escholarship.org/uc/item/7wd3n0nx Tue, 5 May 2026 00:00:00 +0000 Munir, Shaoor https://escholarship.org/uc/item/7t51d9d4 Prostate cancer with distant metastasis (mPCa) is associated with poor prognosis. First-line treatment for localized PCa includes radical prostatectomy (RP) for high-risk disease. Many patients experience androgen receptor (AR)-associated increase of prostate specific antigen (PSA) levels in the serum, aka biochemical recurrence (BCR), increasing potential for mPCa progression. PCa cells that develop resistance to AR based therapies, along with chemotherapy, immunotherapy and radiotherapy, are associated with significant side effects and low overall survival. This dissertation assembles information linking the regulation of BCR to AR-associated metabolic pathways involved with metastatic progression. My goal was to identify metabolic pathways that disrupt BCR and determine potential targets of therapy that eliminate prostate cancer cells unaffected by AR inhibitors.In efforts to achieve this goal, I first conducted metabolomic analysis of prostate tissue from the tumors of 74... https://escholarship.org/uc/item/7t51d9d4 Tue, 5 May 2026 00:00:00 +0000 Spencer Hairston, Dontrel William https://escholarship.org/uc/item/7dd5x3m5 Thin-walled reinforced concrete elements such as slabs, walls, and panels are frequently used in modern construction due to their functionality, material efficiency and architectural flexibility. Under severe loading, however, their behaviors are governed by quasi-brittle fracture processes and the effectiveness of reinforcing strategies, which are difficult to model and control. This is particularly true for cases of out-of-plane loading. To address such modeling and application needs, a particle-based lattice approach is adopted and extended.This dissertation advances the computational modeling of reinforced and thin-walled concrete structures through novel developments of the Voronoi-Cell Lattice Model (VCLM) and its reduced-order layered extension (L-VCLM). Methodological enhancements are introduced to improve the efficiency and accuracy of fracture simulation. In particular, a variable saw-tooth model is proposed, which retains the attributes of conventional event-by-event... https://escholarship.org/uc/item/7dd5x3m5 Tue, 5 May 2026 00:00:00 +0000 Zhang, Qiwei https://escholarship.org/uc/item/7838c0qz Stereotypes in large language models (LLMs) can perpetuate harmful societal biases. De-spite the widespread use of models, little is known about where these biases reside in the neural network. This study investigates the internal mechanisms of GPT-2 Small and Llama 3.2 to locate stereotype-related activations. We explore two approaches: identifying individual contrastive neuron activations that encode stereotypes, and detecting attention heads that contribute heavily to biased outputs. Our experiments aim to map these “bias fingerprints” and provide initial insights for mitigating stereotypes. https://escholarship.org/uc/item/7838c0qz Tue, 5 May 2026 00:00:00 +0000 D'Souza, Alex https://escholarship.org/uc/item/7759s22w Chapter 1 explains a high pass-through of US tariffs at the dock and a low pass-through at the store in general equilibrium in the US-China trade war in 2018. Using a model with costly distribution of traded goods and nominal frictions faced by producers and retailers, this chapter demonstrates that a two-country model without retail-level nominal frictions cannot explain the low pass-through at the store quantitatively. A model with only producer-level nominal frictions requires unrealistically high distribution costs to match the data. Strategy complementarity exists for vertically related firms: exogenous tariff shocks increase downstream retail prices and create incentives for upstream producers to increase their prices. This strategic interaction boosts the tariff pass-through at the dock and helps the model to match the data. Chapter 2 studies financial stability concerns from the rising global capital flows intermediated by investment funds that replicate benchmark... https://escholarship.org/uc/item/7759s22w Tue, 5 May 2026 00:00:00 +0000 Meng, Xiangtao https://escholarship.org/uc/item/70p0r4wp Musculoskeletal tissues, including bone, cartilage, and osteochondral interfaces, exhibit spatially heterogeneous mechanical environments that regulate cell behavior across multiple length scales. In contrast, most engineered biomaterial systems rely on homogeneous and static properties, limiting their ability to capture how spatially organized mechanical cues direct lineage specification. Mesenchymal stromal cells (MSCs) are widely studied for the tissue engineering of musculoskeletal tissues like cartilage and bone, and these cells are highly sensitive to mechanical signals. However, the extent to which MSC fate is governed by the spatial presentation of stiffness, adhesion, and scaffold architecture remains incompletely understood. The central hypothesis of this dissertation is that spatial control of stiffness and scaffold architecture within engineered biomaterials enables region-specific MSC differentiation in three-dimensional environments. We first hypothesized that continuous... https://escholarship.org/uc/item/70p0r4wp Tue, 5 May 2026 00:00:00 +0000 Mierswa, Sabrina Caitlyn https://escholarship.org/uc/item/6vm1w1cg The detrimental impact of wildfire smoke exposure on wine grape growing regions has been intensifying in both severity and frequency. Wildfire smoke contains elevated concentrations of volatile phenols (VPs) that can be absorbed into grapes and negatively impact the quality of grapes and resulting wine. Currently effective mitigation solutions for grapes and wine affected by wildfire smoke exposure are still lacking. Previous research has demonstrated some efficacy of barrier sprays in decreasing smoke VP uptake in wine grapes, but the results indicate that efficiency of such methodology requires further investigation and validation. In this field trial study, two industrial barrier sprays (Kaolin and GM3-E) were selected due to their promising efficacy in prior trials. To Cabernet Sauvignon grapevines, the barrier spray treatment was applied at two time points prior to simulated smoking in smoking tents: 10 days and 21 days, to evaluate the impact of application interval for... https://escholarship.org/uc/item/6vm1w1cg Tue, 5 May 2026 00:00:00 +0000 Kampen, Naomi https://escholarship.org/uc/item/6ts0t3hq California’s differentiated assistance (DA) is intended to function as a structured component of the state’s accountability system by providing technical assistance to local educational agencies whose student groups demonstrate persistent performance challenges across multiple state priorities. However, existing evidence provides limited insight into whether DA operates as a temporary scaffold that supports sustained improvement or as a recurring status that districts repeatedly re-enter. This study uses a quantitative, descriptive, fixed-cohort longitudinal design to the examine the “lifecycle” of DA participation for the 228 traditional school districts first identified for DA in 2017, the inaugural year of the California School Dashboard. Using district-year as the unit of analysis, the study follows this cohort annually through 2024 to document patterns of identification, exit, re-identification, and persistence, and to examine how those trajectories vary by district enrollment... https://escholarship.org/uc/item/6ts0t3hq Tue, 5 May 2026 00:00:00 +0000 Maves, Rachael https://escholarship.org/uc/item/6cb7j7n0 Consistent innovations ever since the end of the 20th century have pushed more and more aspects of human life to transcend into the digital world. Payment systems, education, entertainment, advertising and even healthcare are all examples of real-world structures that are increasingly becoming digital. While this digital revolution has significantly improved the quality of human life, it has also introduced new threats, with diverse entities emerging as bad actors across digital systems.This work proposes a framework to reason about digital identities to defend against bad actors across digital domains. The framework poses five broad questions to guide the design of systems and techniques to establish digital identities. These questions are designed to account for the interests and needs of the various entities within each digital domain, guiding the appropriate trade-offs between security and privacy without compromising on ethics and accessibility. The questions posed by this... https://escholarship.org/uc/item/6cb7j7n0 Tue, 5 May 2026 00:00:00 +0000 Venugopalan, Hari https://escholarship.org/uc/item/5z5479dw Large-scale network-cloud ecosystems are foundational Information and Communication Technology (ICT) infrastructures for current and emerging 5G-Advanced/6G services, making resilience to large-scale disasters a primary societal concern. Unlike single-operator settings, multi-entity ecosystems involve independent carriers and datacenter providers (DCPs) whose infrastructures and operational policies are decentralized. As a result, effective post-disaster recovery increasingly depends on cooperation across entities. However, such cooperation is inherently challenging because proprietary and regulatory constraints limit the disclosure of confidential information, such as detailed topology, restoration plans, and resource availability. This dissertation investigates cooperation-driven recovery and cloud-service restoration in multi-entity network-cloud ecosystems under large-scale failures. To enable cooperation while preserving confidentiality, we introduce a third-party broker,... https://escholarship.org/uc/item/5z5479dw Tue, 5 May 2026 00:00:00 +0000 Sahoo, Subhadeep https://escholarship.org/uc/item/5rc9q076 How disk galaxies, including our own Milky Way, formed and evolved over cosmic time remains an outstanding question in astrophysics. A powerful approach is to treat a galaxy's stellar populations as an archaeological record, one in which the present-day kinematics of stars retains a memory of their galaxy’s past dynamical state. In particular, the age–velocity dispersion relation (AVR), σ(τ) has long served as a probe of stellar dynamical evolution, reflecting both the kinematics with which stars formed – as set by the star-forming interstellar medium – and the dynamical processes that have subsequently altered their orbits. However, interpreting AVRs is inherently ambiguous: similar present-day trends can arise from stars forming with different initial kinematics or from cumulative dynamical heating over time.I use cosmological zoom-in simulations from the FIRE-2 project to disentangle these effects. I find that disk assembly proceeds through three distinct eras, during which... https://escholarship.org/uc/item/5rc9q076 Tue, 5 May 2026 00:00:00 +0000 McCluskey, Fiona https://escholarship.org/uc/item/52b82790 Rare-earth Zintl and polar intermetallic phases are of growing interest because of their intertwined magnetic, electronic, and thermoelectric properties. Eu₅.₀₈Al₃Sb₆ adopts a new monoclinic C2/m structure that can be described as a pseudorock-salt EuSb framework in which Eu-centered Sb octahedra occupy the origin and C-face center, the latter site being shared between Eu (≈8%) and an Al₄ cluster modeled as a dual tetrahedron (≈37.5%). Single-crystal X-ray diffraction on Eu5-xYbxAl3Sb6 and Eu5-x-ySrxYbyAl3Sb6 confirms this structural motif and gives an average valence-electron-per-atom ratio (e/a) of 3.5 for these Eu–Sr–Yb–Al–Sb compositions, consistent with polar intermetallic behavior Al K-edge XANES reveals a shift to higher energy relative to Al metal but slightly lower than AlSb, indicating an intermediate Al oxidation state closer to +3 than 0, and shows little change with Sr content, which suggests that Sr substitution minimally perturbs the Al4 cluster electronics. Polycrystalline... https://escholarship.org/uc/item/52b82790 Tue, 5 May 2026 00:00:00 +0000 Garay, Luis J https://escholarship.org/uc/item/4wn7n4gm Generative models have rapidly advanced in recent years, enabling the synthesis of increasingly complex content across modalities such as language, image, and video. As generative capabilities expand from single-turn text generation to multimodal reasoning, tool use, and long-horizon video synthesis, the nature of evaluation has fundamentally changed. Traditional rule-based or reference-dependent metrics, originally designed for well-defined and short-form tasks, are often inadequate for assessing modern generative systems. They fail to comprehensively capture output quality, semantic and factual correctness, instruction alignment, and broader human and societal considerations such as bias, safety, and fairness. As generative systems become more open-ended, interactive, and agentic, evaluation methods should move beyond coarse-grained scoring toward structured, multi-dimensional, and interpretable assessment. To this end, this dissertation presents a series of studies that... https://escholarship.org/uc/item/4wn7n4gm Tue, 5 May 2026 00:00:00 +0000 Liu, Xiao https://escholarship.org/uc/item/4td6p3t0 This dissertation reframes oligopsonistic power in agricultural procurement as time-varying rather than fixed, showing how buyer competition waxes and wanes within a single marketing season and how farmers use storage to shift when, and on what terms, they sell. Using China's fresh-apple sector as the empirical setting, I argue that storage is not only a vehicle for intertemporal arbitrage but a lever that reallocates relative power toward smallholders when oligopsony conditions loosen over time. I build a two-period model in which buyer power is time-varying and farmers equipped with storage can optimally ``wait into'' possibly more competitive windows. The framework cleanly separates buyer-power dynamics from demand shocks and illuminates how expectations about the future competitive conditions among rivalry and risk preferences jointly determine storage choices and realized selling conditions. Numerical simulations with heterogeneous risk preferences map storage efficiency... https://escholarship.org/uc/item/4td6p3t0 Tue, 5 May 2026 00:00:00 +0000 Ma, Zhiyao https://escholarship.org/uc/item/4rg5m6nx Harmful cyanobacterial algal blooms (cHAB) are becoming increasingly frequent and persistent in freshwater systems. The massive proliferation of cHAB could be driven by a range of factors, including changes in nutrient loading, hydrodynamic stability, and climate change. Their proliferation poses significant risks to human health, especially since cyanobacterial blooms can produce various cyanotoxins and can serve as precursors of disinfection by-products (DBPs). Addressing the behavior and lingering effects of cHAB requires improved monitoring tools capable of resolving their spatiotemporal variability, along with treatment strategies that can reliably mitigate the risks associated with cHAB. This dissertation addresses these needs by integrating sensor engineering, lake physics, microbial ecology, and full-scale treatment evaluation.Chapter 1 focuses on the development and validation of a low-cost UV-C fluorometric sensor capable of detecting phycocyanin, phycoerythrin, and... https://escholarship.org/uc/item/4rg5m6nx Tue, 5 May 2026 00:00:00 +0000 Pinkanjananavee, Kanarat https://escholarship.org/uc/item/4hc8b69d Arctic ecosystems are experiencing rapid climate warming with profound consequences for vegetation dynamics and herbivore populations. Migratory caribou (Rangifer tarandus), which depend on nutrient-rich forage during the calving and lactation period, have declined sharply across the Arctic, including in West Greenland. Two processes linked to warming, earlier tundra green-up and increasing shrub dominance, are expected to reduce forage quality and increase the risk of phenological mismatch between caribou nutritional demand and plant nutrient availability. To assess these dynamics, I analyzed foliar nitrogen, carbon, and C:N ratios in three key forage taxa (Poa spp., Betula nana, and Salix glauca) across the 2023 growing season near Kangerlussuaq, Greenland, and in a parallel experimental warming treatment. Results showed a significant seasonal decline in graminoid quality, with Poa exhibiting declining nitrogen and rising C:N ratios across the calving season, consistent with... https://escholarship.org/uc/item/4hc8b69d Tue, 5 May 2026 00:00:00 +0000 O'Connor, Bradyn https://escholarship.org/uc/item/4c54j7x3 Perennially ice-covered Antarctic lakes allow the separation of biological and physical controls on dissolved oxygen (DO). We analyzed year-round DO and temperature from Lake Fryxell in 2023-2024 across four datasets: in the water column and near the lake floor (benthic) using HOBO and miniDOT DO and temperature loggers. We also integrated wind records from the Lake Fryxell meteorological station. Using Fast Fourier Transform (FFT), continuous wavelet transform (CWT), Spearman correlations with wind, lag tests, and wavelet coherence (WTC), we quantified seasonal and event-scale variability. In summer, the benthic records show strong diel (~1 day) variability, consistent with light-driven oxygen production by benthic photosynthesis. With the onset of polar night, the diel band collapses. The water-column dataset exhibits a net decline in DO during winter 2023, whereas the benthic datasets display event-driven variability without a uniform seasonal drawdown. Three lines of evidence... https://escholarship.org/uc/item/4c54j7x3 Tue, 5 May 2026 00:00:00 +0000 Cortes, Luis Angel https://escholarship.org/uc/item/4bk9w099 As climate change poses an increasing threat to communities here in California, there will be an increase in people displaced by various climate threats. Focusing on fire, this study asks three research questions: 1) What effects does climate migration have on receiving communities? 2) How do members of receiving communities think about these effects? 3) How are climate migrants perceived by community members? Using a mixed methods approach consisting of census data and qualitative content analysis for the case study of Chico, California. Findings indicate that community members feel squeezed out, particularly in issues of housing, job availability, and medical care; and that residents feel an increase in homelessness and overall cultural shift. This thesis is important for community and regional policy as it demonstrates the vital role that receiving communities play in building resilience for climate migration. Residents highlight the need for more resources and better governance... https://escholarship.org/uc/item/4bk9w099 Tue, 5 May 2026 00:00:00 +0000 Marhenke, Julia https://escholarship.org/uc/item/3wn783g3 Subduction zones are complex, self-organized systems in which plate buoyancy, mantle rheology, metamorphic processes, and geometry interact to control slab deformation, trench motion, and mantle flow. Understanding how these processes couple across spatial scales and modeling frameworks remains a central challenge in geodynamics. This dissertation investigates the physical controls on subduction dynamics using a suite of two- and three-dimensional free-subduction models that progressively incorporate physically based rheology, compositionally dependent phase transitions, and geometric effects.The first part of this work focuses on the plate boundary shear zone, which transitions from a brittle fault near the surface to a ductile shear zone at depth. Rather than prescribing a weak layer with an arbitrary cutoff depth, the shear zone viscosity is linked to the basalt–eclogite phase transition, providing a physical mechanism for the emergence of a globally consistent mantle decoupling... https://escholarship.org/uc/item/3wn783g3 Tue, 5 May 2026 00:00:00 +0000 Li, Haoyuan https://escholarship.org/uc/item/3v82w3j1 Stomatal conductance (gs) quantifies the rate of CO2 uptake and water loss through stomata, linking plant productivity with water use and making it a key trait for understanding crop performance across environments. However, the wide adoption of gs in plant breeding programs has been limited by the high labor cost of gs direct measurement and by the difficulty of separating genotype-specific stomatal behavior from confounding environmental effects in gs and gs proxy measurements such as leaf temperature. Thus, this work developed and validated a comprehensive framework that would allow high-throughput phenotyping of gs using thermal imagery to extract genotype-specific stomatal traits, and demonstrated their utility for improving genotype × environment (G×E) prediction in cowpea breeding trials. The sensitivity of leaf temperature (Tleaf) to gs was first systematically quantified using the Helios 3D biophysical modeling framework across a range of environmental conditions, measurement... https://escholarship.org/uc/item/3v82w3j1 Tue, 5 May 2026 00:00:00 +0000 Mayanja, Ismael Kilinya https://escholarship.org/uc/item/3sn016sf With a few fundamental postulates, one can fully describe the thermodynamic equilibrium state of a system. An equilibrium state, by definition, is stable: the macroscopic quantities of interest do not change with time. However, real systems are rarely in true equilibrium, as they constantly exchange energy, matter, and information with their surroundings. Fortunately, many systems—such as a hot cup of coffee on a winter day—can be approximated as being in local equilibrium, allowing their behavior to be described by the simple framework of equilibrium thermodynamics.Near equilibrium, Onsager first introduced a framework with a linear assumption in 1930s. Onsager successfully described the coupling between thermal diffusion and thermoelectric. His approach to nonequilibrium is now called linear response theory, which works well near equilibrium. Surprisingly, an approach to systems far from equilibrium was developed by Langevin in the early 1900s—well before the advent of linear... https://escholarship.org/uc/item/3sn016sf Tue, 5 May 2026 00:00:00 +0000 Lyu, Jinghao https://escholarship.org/uc/item/3fv9z1ns Scientific applications rely heavily on floating-point computations to model complex phenomena in physics, chemistry, biology, and other scientific domains. However, floating-point arithmetic is inherently imprecise and can lead to numerical inconsistencies that affect the correctness and reliability of scientific software. Additionally, optimizing these applications to efficiently utilize modern high-performance computing resources is a significant challenge.This dissertation addresses these challenges through four complementary approaches using program analysis and testing techniques to facilitate debugging and optimization of scientific applications. First, we present Ciel, a tool that uses bisection search and precision enhancement for enhanced isolation of compiler-induced numerical inconsistencies in heterogeneous code, helping developers identify the expressions that cause unexpected numerical behavior. Evaluation demonstrated 99.4% precision across 330 GPU programs and... https://escholarship.org/uc/item/3fv9z1ns Tue, 5 May 2026 00:00:00 +0000 Miao, Dolores https://escholarship.org/uc/item/2mp442gp Regenerative abilities vary widely across animals, even among closely related species, and a central challenge is to compare their gene regulatory networks (GRNs) to determine which components and regulatory connections are conserved or divergent. Hydra provides a powerful system for this work: as a cnidarian, which is the sister group to bilaterians, it offers access to deeply conserved regenerative mechanisms, and species within the genus differ in regenerative phenotypes. Here, we investigate the function of extracellular signal-regulated kinase (ERK) signaling in driving head regeneration in Hydra. ERK is a conserved injury-responsive pathway implicated in regeneration across animals, including in the activation of Wnt signaling, which is necessary and sufficient to establish the Hydra head organizer, a Wnt signaling center that patterns the main body axis. We found that in Hydra vulgaris, ERK activity extends from the generic injury phase into the period when the Wnt-based... https://escholarship.org/uc/item/2mp442gp Tue, 5 May 2026 00:00:00 +0000 Juanico, Iris Yoshiko https://escholarship.org/uc/item/2g38q9d5 Global change threatens natural environments worldwide. Ecosystem impacts and responses will be shaped by the extent to which populations are able to adapt to rapidly changing conditions (adaptive capacity). In the marine environment, foundation species play central roles in generating habitat, structuring community interactions, and mediating resource availability, but they are frequently sensitive to environmental change. As sea surface temperatures rise, many populations are experiencing strong, directional selection on increased thermal tolerance. Despite evidence in multiple species that there exists phenotypic and genetic variation that could fuel adaptation to warming, patterns of response remain difficult to predict due to the immense complexity of thermal tolerance.In my dissertation, I investigated how multivariate phenotypes interact with environmental drivers to shape adaptation to temperature and responses to warming in two widespread, ecologically important marine... https://escholarship.org/uc/item/2g38q9d5 Tue, 5 May 2026 00:00:00 +0000 Benson, Brooke https://escholarship.org/uc/item/2ff8g75x Social media platforms increasingly shape how young adults access health information and make decisions about skincare and cosmetic procedures. In dermatology, where visual outcomes and consumer-facing products are prominent, social media has become a primary source of guidance, often driven by influencer content that emphasizes aesthetic results rather than clinical accuracy. While existing research has largely focused on women’s engagement with skincare content, the influence of social media on dermatological decision-making among young American men remains under-examined. This study examines how social media trends influence young men’s dermatologic product use and interest in dermatological procedures, with particular attention to the gap between highly engaging online content and evidence-based dermatological practice. Using a mixed-methods health informatics approach, the study combines qualitative content analysis with quantitative engagement analysis of TikTok posts across... https://escholarship.org/uc/item/2ff8g75x Tue, 5 May 2026 00:00:00 +0000 Toston, David Matthew https://escholarship.org/uc/item/2f3157vq California's current specifications limit reclaimed asphalt pavement (RAP) content to 25% by aggregate replacement for dense-graded hot mix asphalt, despite the successful construction of pilot projects with substantially higher recycled binder content. This research evaluates ten asphalt mixture designs from two California Department of Transportation pilot projects, State Route 49 in El Dorado County (ELD 49) and Interstate 215 in San Bernardino County (SBD 215), across performance, economic, and environmental dimensions. The ELD 49 project evaluated conventional asphalt binders with up to 10% RAP and 3% recycled asphalt shingles (RAS), while SBD 215 examined polymer-modified binders with up to 40% RAP.Using California Mechanistic Empirical pavement design software (CalME) , life-cycle cost analysis, and life-cycle assessment, this study analyzed each mix design across three California climate zones (High Mountain, Desert, South Coast) at a Traffic Index of 12 corresponding... https://escholarship.org/uc/item/2f3157vq Tue, 5 May 2026 00:00:00 +0000 Mohammed, Hanif https://escholarship.org/uc/item/2c61h5sm White (Acipenser transmontanus) and Green Sturgeon (Acipenser medirostris) are two of the largest freshwater fish species inhabiting the west coast of North America. Ancient fish with complex life histories, sturgeons have persisted since the Jurassic period, yet their populations have experienced significant declines since the nineteenth century. These declines are primarily attributed to anthropogenic factors including overfishing, habitat modification, water diversions for agriculture, and exposure to environmental contaminants. Early life stages of sturgeon, critical for population recruitment, are especially susceptible to these stressors, which may impair their growth, survival, and migration capabilities necessary for reaching maturity and successfully reproducing. Therefore, this dissertation examines how physical and chemical stressors associated with regulated water systems influence survival, physiology, and behavior of green and white sturgeon during critical early... https://escholarship.org/uc/item/2c61h5sm Tue, 5 May 2026 00:00:00 +0000 YANG, DUOLI https://escholarship.org/uc/item/2987x0v7 Phytoplankton are a critical but limited resource supporting pelagic food webs in the San Francisco Estuary (SFE), where declines in primary production have contributed to food limitation for native fishes, including the endangered Delta smelt. Despite high nutrient availability, phytoplankton biomass and productivity remain low across much of the estuary due to light limitation, short residence times, and grazing pressure from invasive clams. Shallow water habitats are recognized as a major source for localized production, and thus tidal restoration is used to enhanced phytoplankton production that may subsidize adjacent tidal habitats. Other shallow water habitats exist and are largely unexplored: managed wetlands. This dissertation examines how hydrologic management and hydrologic connectivity to adjacent tidal sloughs structure phytoplankton biomass and productivity in seasonally managed wetlands of Suisun Marsh, CA.Chapter 1 focuses on a seasonally managed wetland (Luco Pond)... https://escholarship.org/uc/item/2987x0v7 Tue, 5 May 2026 00:00:00 +0000 Tung, Alice https://escholarship.org/uc/item/25g0x8zg This paper presents an examination of feminine virtue in the Valmiki Ramayana in light of the epic’s dominant patriarchal and misogynistic ideology. Considering Valmiki’s male ascetics as exemplars of male-coded dharma, I contrast these figures with the precariously positioned female ascetics, women depicted as awesome and frightening unless chaperoned by their male counterparts. Drawing on extensive scholarship about ancient laments, I suggest how the five female-led funerary laments in the epic reveal Valmiki’s suspicions about the extent to which women will rely on sensual or pitiable performances to influence patriarchs and disrupt social order, suspicions that likewise motivate the poet’s treatment of female ascetics. In doing so, I necessarily appraise the value of dharmic cultivation for correcting disruptive female behavior and find that even cultivated women like Sita must still suffer the moral fallibility parcel to their gender. My argument culminates in a statement... https://escholarship.org/uc/item/25g0x8zg Tue, 5 May 2026 00:00:00 +0000 Dyer, Daniel Peter Winston https://escholarship.org/uc/item/2476v6bg Wildfire can negatively impact air, soil, and water quality, and increase the mobilization of anthropogenic and geogenic contaminants. Dissolved organic matter (DOM), in particular, sulfur (S) functional groups in DOM, are known to influence the fate and transport of trace metals in aqueous systems. Thus, knowledge of the impact of fire on DOM lability and composition post fire is needed to evaluate how wildfire modifies elemental cycles. Two representative end-member soils were evaluated, a low organic matter mineral soil (4.8% total organic carbon (TOC)) and a high organic matter peat soil (50% TOC), were heated at temperatures relevant of wildfires under the following conditions: (1) varied temperature (ambient, 75 °C, 125 °C, 150 °C, 200 °C, 300 °C) at constant heating time (1 hour) or (2) constant temperature (125 °C) at variable heating time (0.25-4.0 hours). Following laboratory heating, soils were leached using a synthetic freshwater of low ionic strength, and leachates... https://escholarship.org/uc/item/2476v6bg Tue, 5 May 2026 00:00:00 +0000 Murray, Jeff Scott https://escholarship.org/uc/item/1zx8x6z1 7,8-Dihydroxyflavone (7,8-DHF) is a tyrosine receptor kinase B agonist that has been demonstrated to show therapeutic promise for treatment of several neuropsychiatric disorders, as well as injuries, of the central nervous system. Unfortunately, there is a gap in the delivery system for this drug as its pharmacokinetics could be improved upon by increasing its clearance time, while retaining the ability to affect neuronal cell types towards protection and proliferation. To this end, the loading of liposomes and extracellular vesicles with the small molecule has been posited as an effective delivery mechanism. As a hydrophobic drug, a scalable, efficient 7,8-DHF loading strategy that simultaneously produces homogenous particles for accurate therapeutic dosing is currently an unmet need. In service of this problem statement, we propose the optimization of the microfluidic-based NanoAssemblr Ignite LNP formulation platform first for the loading of a DOPC and cholesterol-based liposome,... https://escholarship.org/uc/item/1zx8x6z1 Tue, 5 May 2026 00:00:00 +0000 Humphries, Abigail Leigh https://escholarship.org/uc/item/1pp7m8tb Residential buildings account for approximately 20% of total U.S. greenhouse gas emissions, with a substantial fraction arising from fossil-fuel-based space and water heating. Electrification using air-source heat pumps offers a promising pathway to reduce these emissions; however, conventional retrofit approaches that rely on separate systems for space conditioning and domestic hot water (DHW) often face prohibitive costs and electrical infrastructure constraints. In particular, the combined electrical demand and reliance on electric resistance backup frequently necessitate costly panel upgrades, limiting adoption, especially in older and low-income housing stock.This dissertation investigates whether air to air multi function heat pumps (MFHPs), which integrate space heating, space cooling, and domestic hot water production into a single system, can fundamentally address these barriers and serve as a viable alternative pathway for residential electrification. The central research... https://escholarship.org/uc/item/1pp7m8tb Tue, 5 May 2026 00:00:00 +0000 Chakraborty, Subhrajit https://escholarship.org/uc/item/0f67n270 Cryptococcus neoformans (Cn) is an opportunistic, neuroinvasive fungal pathogen that causes life-threatening meningoencephalitis and frequently results in long-term cognitive impairment despite antifungal treatment. Cn gains access to the central nervous system (CNS) by traversing the blood–brain barrier (BBB), yet the molecular mechanisms governing fungal entry into brain endothelial cells remain incompletely understood. The disproportionate global burden of Cryptococcal meningoencephalitis (CM) underscores the need to define the host-pathogen signaling events that enable BBB infiltration and to develop improved therapeutic strategies. In this thesis, I first establish the cellular and molecular architecture that regulates trafficking across the BBB and outline canonical mechanisms of microbial entry, focusing on Cn as a clinically urgent model of fungal neuroinvasion. I then demonstrate, using both human three-dimensional BBB organoids and conventional two-dimensional in vitro... https://escholarship.org/uc/item/0f67n270 Tue, 5 May 2026 00:00:00 +0000 Bennett, Amelia Brie https://escholarship.org/uc/item/06f1516f Sexual minority well-being is a growing public health concern, as many studies find that they report lower levels of well-being compared to heterosexuals. Minority stress theory, the predominant framework used to explain these differences, proposes that well-being differences emerge because sexual minorities face additional identity-based stressors that add more general stress. That is, sexual minorities face additional interpersonal (e.g., discrimination) and structural (e.g., stigmatizing policies) stress because of people and society’s negative reaction to their sexual identity. Over time, heightened experiences of these stressors can result in internalizing negative feelings about one’s minoritized sexual identity, resulting in further minority stress. While much research has supported the theoretical assumptions of minority stress theory, there are two broad shortcomings of the extant research. This dissertation aims to address these in two chapters. First, much of... https://escholarship.org/uc/item/06f1516f Tue, 5 May 2026 00:00:00 +0000 Nissen, Adam Taylor https://escholarship.org/uc/item/05m9j143 Microgravity has been associated with increased arrhythmia risk in astronauts, yet the mechanisms underlying this vulnerability remain poorly defined. Experimental evidence suggests that cardiomyocytes under microgravity conditions exhibit changes in ion channel expression and function, mediated by alterations in biochemical signaling and oxidative stress, which could destabilize cardiac action potentials and increase arrhythmia vulnerability. Here we aim to develop a model of cardiomyocyte electrophysiology that integrates experimental results to understand the mechanisms of heightened arrhythmia risk in microgravity conditions. We adapted a well-established model of the rabbit ventricular myocyte action potential to incorporate experimentally reported microgravity-induced remodeling of L-type Ca2+ channels (LTCCs), ryanodine receptors (RyRs), sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) pumps, and Na+/K+ pumps. We then quantified the effects of microgravity remodeling on... https://escholarship.org/uc/item/05m9j143 Tue, 5 May 2026 00:00:00 +0000 Bak, Tymoteusz Franciszek https://escholarship.org/uc/item/04j081bv A computation transforms inputs into outputs. Understanding the fundamental physics of computing can then reveal how to perform computations as energy efficiently as possible. Making progress on this front began with Rolf Landauer in 1961. Using a single bit of information, Landauer investigated the information erasure operation, which erases input information to produce an output. Performing this operation results in the dissipation of a minimum theoretical amount of energy from the system into the thermal environment, that being kBT  \ln 2, where kBT  is the Boltzmann constant and T is the temperature of the heat bath. Achieving this bound requires the computation to be performed infinitely slowly. Though not very practical, the Landauer bound illuminates a physical limitation that all computing devices are subjected to: Erasing information requires dissipating energy.After several decades of development, computers built from complementary metal-oxide semiconductors... https://escholarship.org/uc/item/04j081bv Tue, 5 May 2026 00:00:00 +0000 Pratt, Christian https://escholarship.org/uc/item/8cv215gk This dissertation is based on twelve months of fieldwork on ecovillages in China. The main field site is located in the rural mountain areas of Hangzhou, far away from nearby towns and cities. Ecovillagers comprise a diverse group of people who envision a low-cost, low environmental-impact way of life. They have been curating a wide range of eco-skills, including chopping wood, making fire and charcoal, growing food and composting, practicing Chinese medicine, constructing buildings with nontoxic biodegradable materials, and divining I Ching hexagrams. These skills meet daily survival needs at minimal cost, reduce reliance on existing institutions, and extend care to the surrounding environment. Some of these skills were learned from local elders who remained in the villages; others were acquired through workshops within domestic and global ecovillage networks. Many of these workshops draw from international ecological movements such as permaculture and cob house building.... https://escholarship.org/uc/item/8cv215gk Fri, 1 May 2026 00:00:00 +0000 Yin, Yuting https://escholarship.org/uc/item/4686j3fp Water is the most shared resource in the world, critical for shaping ecological, social, and economic systems. Yet, its availability is constrained by climate variability, human use, and historical water management frameworks. While water scarcity can lead to conflict among nations, states, or individuals, it also frequently fosters collaboration. Tensions typically arise when the resource is scarce, geographically dispersed, or tied to environmental, political, or economic interests. This study analyzes water availability and flow regimes in the Rio Grande/Rio Bravo basin to assess a resilient flow regime. I apply the principles of hydrologic variability, resilience, and functional flows to understand how the river can sustain itself under changing conditions. The research also includes an evaluation of the Pecos River's historical and contemporary flow regimes to assess human impacts and the implications of water agreements.In this work, I introduce the concept of a resilient... https://escholarship.org/uc/item/4686j3fp Wed, 11 Feb 2026 00:00:00 +0000 Saiz Rodriguez, Ramon https://escholarship.org/uc/item/2544f3jb The construction sector accounts for a significant share of global energy use and embodied CO2 emissions. It is estimated that a 10-20% embodied carbon reduction in buildings can be achieved by utilizing cement substitutes and other low-impact materials. One method that could potentially minimize industrial processing and transportation is the use of locally available earthen construction materials. Earthen materials generally use locally available soil to produce durable structural solutions, particularly for family dwellings and other low-rise buildings. This practice has been a successful construction method for centuries across different climates and cultures. Although producing earthen blocks provides a low-energy alternative to fired bricks and other construction materials, the process of making the blocks and installing them is still time-consuming and labor-intensive. Variations in local soil conditions or manufacturing techniques may also lead to uncontrolled variations... https://escholarship.org/uc/item/2544f3jb Wed, 11 Feb 2026 00:00:00 +0000 Nodehi, Mehrab https://escholarship.org/uc/item/0wf3x0mb This work aims to develop a superfluid helium experimental platform that simulates the neutron star glitch phenomenon. To simulate the physical surroundings of neutron stars, the rotation probe is magnetically levitated, spun up by an induction motor, and measured with an optical rotation spectrometer. The implementation details of the levitation, motor, measurement, and damping systems are introduced in detail. Interferences from the ambient magnetic field, ferromagnetic objects, non-ideal apparatus, and aerodynamics are analyzed, then partly or fully resolved. This work presents and analyzes the principal parameters of glitches—including duration, occurrence rate, rotation velocity, its derivative, and activity—and compares them directly with measurements from neutron stars. We discovered that there exists a clear inverse proportional relation between the duration of glitches and the rotation speed. The glitch rate is positively correlated with the rotation velocity and the... https://escholarship.org/uc/item/0wf3x0mb Wed, 11 Feb 2026 00:00:00 +0000 Zhou, Haoyang https://escholarship.org/uc/item/0s18v8x4 Understanding phase transitions in materials is central to advancing both fundamental science and functional technologies. This thesis investigates phase transitions in two distinct systems— La1−xSrxCoO3 (LSCO) perovskite oxides and F- and Ge-doped silica glasses—using X-ray diffraction techniques at synchrotron sources and free electron lasers.For LSCO system, I focused on the nanodiffraction measurements of the oxygen-driven perovskite-to-brownmillerite transition, a structural change with significant tunability in ionic conductivity and magnetism. Conventional nanodiffraction data analysis often fails to quantitatively provide any details on the emergent brownmillerite phase. To address this gap, I applied, the Earth Mover's Distance (EMD) algorithm, originally developed for computer vision, as a novel analytical tool for nanoscale diffraction datasets to quantitatively compare brownmillerite phase in different regions following transition in LSCO thin films. Mapping EMD values... https://escholarship.org/uc/item/0s18v8x4 Wed, 11 Feb 2026 00:00:00 +0000 Li, Cunshuo https://escholarship.org/uc/item/9z66x4vf Abstract: Megafires are increasingly common across western North America and can alter wildlife populations at broad scales. To better evaluate the effects of megafires, we assessed the impact of the 2021 Dixie Fire on American black bears (Ursus americanus) in Lassen Volcanic National Park (LVNP), for which the fire burned about 69% of LVNP. We conducted both prefire (2017–2018) and postfire (2023–2024) sampling using remote cameras and hair snares at 33 georeferenced sites, which allowed us to assess changes in detection probability, occupancy, habitat use, movement, and density. Site occupancy remained high and unchanged between both sampling periods (prefire ψ = 0.84 ± 0.07; postfire ψ = 0.82 ± 0.13). After the fire, bears shifted to surviving red fir (Abies magnifica) forests at a 500-meter scale, suggesting increasing use of remaining patches. Capture-recapture analysis showed a significant population decline: total bears declined by 63% (19.3 to 7.1 bears/100 km²), females... https://escholarship.org/uc/item/9z66x4vf Mon, 9 Feb 2026 00:00:00 +0000 Ruka, Daniel https://escholarship.org/uc/item/9kd9s44s Forensic scientists can potentially identify the relation between touch DNA and the crime scene in question, including where the evidence was discovered, how it was collected, potential sample amount lost during testing, and whether the amount recovered is sufficient to generate a DNA profile and connect a suspect to a crime. This study focuses on comparing primary and secondary pathways involving touch DNA transfer on cellphone protection screens. These pathways were investigated using both domesticated and wild fingerprints where a sample containing a known quantity of DNA was used to calculate a mock fingerprint, in order to run two different pathways.Each pathway represents a different scenario: 1) the primary pathway involved a male participant touching a cellphone screen, 2) the secondary pathway involved a male participant shaking hands with a female participant, who then touched the cellphone screen. Touch DNA was collected from the cellphone screens, from the thumbs of... https://escholarship.org/uc/item/9kd9s44s Mon, 9 Feb 2026 00:00:00 +0000 Reyes, Angel Mauricio https://escholarship.org/uc/item/8xs3c67q Shared micromobility use has the potential to improve physical and mental wellness. As bike share and scooter share systems become more popular and the effects of their use more understood, it is important to consider how users perceive these systems to be affecting them. How users perceive the effects of riding shared micromobility may influence how much they choose to ride, and their riding experiences may in turn shape those perceptions. Additionally, how safe users feel when using bike share and scooter share is important in evaluating if the built environment is adequately serving these users as changes in design are made over time to better accommodate walking, bicycling, and scooting in cities. Active travel modes like bicycling also provide a healthier alternative to driving, and it is useful to know if users of bike share and scooter share feel they are experiencing more physical activity as a result of their use of micromobility. Therefore, in this dissertation I include... https://escholarship.org/uc/item/8xs3c67q Mon, 9 Feb 2026 00:00:00 +0000 Darr, Justin https://escholarship.org/uc/item/8ms6k6qq Regular expressions (RegEx) are sequences of characters that define search patterns to be used when searching data. They play a vital role in domains such as network intrusion detection, bio-informatics, system log analysis, large-scale data mining., etc. This thesis proposes a framework for regular expression processing on a fine-grain many-core platform. The framework supports 38 RegEx symbols through the introduction of 20 distinct many-core kernels. The framework uses two sets of python scripts to parse RegEx symbols and generate corresponding many-core kernels with their interconnections, respectively. Each of the 20 individual many-core kernels has single C++ implementation versions. All of these implementations were profiled and evaluated in terms of input throughput (Char/sec), energy efficiency (J/Char), and clock cycle consumption (Cycles/Char). To evaluate the framework's algorithms and software, a benchmark regular expression implementation is also described and profiled,... https://escholarship.org/uc/item/8ms6k6qq Mon, 9 Feb 2026 00:00:00 +0000 Sajeev, Sagar https://escholarship.org/uc/item/8hg4w25t Speakers vary in how they produce language, and this variation can be stylistic, socially motivated, or based on individual differences. In human language, all communication has social meaning (Giles & Ogay, 2013; Eckert, 2012). But, it is unknown how the same variation would be perceived in “intelligent” computers like voice AI assistants and chatbots. Previous research has shown that when faced with increasing cues of humanity, users apply gender stereotypes, show politeness, linguistically align with, and anthropomorphize social computers (Cohn et al., 2023; Nass, et al., 1997; Sundar & Kim, 2012). Yet, it is unknown whether users evaluate social computer behavior as socially meaningful. Because of the importance of sociolinguistic variation in the generation of social meaning, the use of social-indexical variation by computer voices is an apt way to investigate whether users evaluate computers as social actors.In three experiments, this dissertation research investigated... https://escholarship.org/uc/item/8hg4w25t Mon, 9 Feb 2026 00:00:00 +0000 Keaton, Ashley Rose https://escholarship.org/uc/item/8267j05z HMoob histories have traditionally centered their experiences in America as refugees. Recently, critical scholars have unsettled various tellings of HMoob experiences. Thus, showing that HMoob people are more than just refugees. Often, HMoob women's experiences are ignored in these scholarships. Using a Critical Indigenous Studies, Chicanx Feminist framework, and critical refugee studies, I trace the experiences of HMoob Caub Fab Elders, from their survival through war and their distinct way of seeing the world. Thus far, Caub Fab remains an unpopular discourse among HMoob communities. I use a collection of oral histories from seven HMoob Elders who identify as Caub Fab currently living in Sacramento and Fresno, California. Additionally, I also draw from my own autoethnographic experiences, to show that the mainstream HMoob refugee narrative is extremely violent and limiting for my lived experience as a HMoob woman. (Un)Married HMoob women are told they are severed from their... https://escholarship.org/uc/item/8267j05z Mon, 9 Feb 2026 00:00:00 +0000 vang, karen bao https://escholarship.org/uc/item/80f1q3fb This thesis draws on multiple studies from those that leverage large-scale data architectures to studies exploring the causal relationships between genes and phenotypes. The first chapter focuses on extrapolating biologically meaningful insight from large-scale data using bioinformatics. Large genomics, phenomics, and metabolomics studies commonly rely on dimensionality reduction and network based approaches to interpret how genetic variation shape’s biological function. The analytical approaches chosen can strongly influence the resulting biological insights gleaned from the study. For example, in QTL mapping, principal component analysis (PCA) can simplify complicated omics datasets but may generate a fundamentally different view of the underlying genetic architecture compared to individual trait mapping and hotspot analysis. This underscores how data reduction strategies need to be carefully vetted for usage in genetic mapping to ensure the specific question of interest is... https://escholarship.org/uc/item/80f1q3fb Mon, 9 Feb 2026 00:00:00 +0000 Keller, Caroline Kaley https://escholarship.org/uc/item/6rg6f0zm Gray mold (Botrytis cinerea) is a key postharvest pathogen affecting table grapes. This study presents a chemical approach to achieving controlled and sustained sulfur dioxide (?? ) release through the reaction of sodium metabisulfite with water and citric 2 acid. Reaction kinetics and ?? release behavior were systematically analyzed to 2 illustrate kinetic modeling, optimal ratios, and improved ?? yield in the presence of 2 citric acid. Citric acid dramatically enhanced ?? release rate and extent, supporting the 2 application of metabisulfite with citric acid for postharvest fungal inhibition in grape storage. Traditional metabisulfite treatment alone was found to have a very slow release rate and yield, making this approach ineffective. https://escholarship.org/uc/item/6rg6f0zm Mon, 9 Feb 2026 00:00:00 +0000 Hou, Jiayun https://escholarship.org/uc/item/6f66q8b0 As the State of California enacts regulations in order to transition internal combustion engine trucks to zero emission trucks, it is important for regulators and policymakers to have an understanding of the technologies they are able to utilize. A new technology and business model has rapidly expanded in China, the world’s most advanced zero emission vehicle and truck market, but is not well understood elsewhere. This technology and business model, known as battery swapping, is prominent in the heavy-duty truck industry and is expanding to other vehicle/transportation segments. This paper implements a total cost of ownership model to test and compare the $/ton-mile costs associated with owning and operating plug in battery electric and battery swap heavy-duty trucks. This study builds upon past models used to determine the total cost of ownership of trucks, however, this study’s novelty is the analysis of different utilization rate and battery size scenarios, the monetization... https://escholarship.org/uc/item/6f66q8b0 Mon, 9 Feb 2026 00:00:00 +0000 Hughes, Timothy https://escholarship.org/uc/item/69d7c1vb Mycobacteria is a genus of bacteria with numerous notable pathogens, including M. tuberculosis, which is a human adapted lung pathogen and leading cause of death worldwide, and M. abscessus, an opportunistic pathogen which can also infect the lungs and is a leading cause of death in cystic fibrosis patients. Notably, both infections are difficult to treat with antibiotics and require extended treatment of months to years. Antibiotic tolerance is a phenomenon where cells adopt a physiological state which allows them to survive for extended periods in lethal antibiotics. Antibiotic tolerance is often induced by environmental stress conditions, including immune-related stresses such as nutrient starvation, and is thought to be an obstacle to antibiotic treatment clinically. We sought to identify the genetic factors which underlie antibiotic tolerance by running loss of function genetic screens. In M. abscessus, we identified numerous tolerance regulators to the translation inhibiting... https://escholarship.org/uc/item/69d7c1vb Mon, 9 Feb 2026 00:00:00 +0000 Bates, Nicholas Arthur https://escholarship.org/uc/item/67620031 In this dissertation, I pursue two goals. The first is exploratory, insofar as I explore the ways in which one could adopt a pluralistic approach to biological sex. The second is to develop what I call a situated-process pluralist framework that can apply beyond scientific classifications of sex. I do this by comparing three frameworks. I start by extracting key insights from John Dupré’s promiscuous realist pluralism with respect to natural kinds and Marc Ereshefsky’s eliminative pluralism with respect to species and then apply them to biological sex. I then compare these views with Sarah Richardson’s sex contextualism. I extract four features of comparison: their dialectical point of tension, their metaphysical commitments and assumptions, their epistemic commitments, and their semantic commitments. I ask three questions: 1) what grounds the legitimacy of sex classification on each of the views, 2) how those assumptions and commitments travel across context, and 3) what follows... https://escholarship.org/uc/item/67620031 Mon, 9 Feb 2026 00:00:00 +0000 Haddal, Natasha Maria https://escholarship.org/uc/item/5sr1v7rg Concrete is an essential material in the built environment and plays a critical role in infrastructure and urban development. The demand for concrete is expected to accelerate with growing populations and urbanization. Currently, the production of concrete is causing notable environmental impacts. Recent estimates have put global concrete production as contributing approximately 8% of anthropogenic CO2 emissions annually. The manufacturing of cement, the hydraulic binder that binds rocks together in concrete, is the main source of CO2 emissions from concrete. Most of these emissions are derived from clinker production—a kilned and quenched material used to produce cement. These CO2 emissions stem from both the decarbonation of limestone and the combustion of fossil fuels required to generate the high temperatures necessary for clinker formation. Decarbonizing the concrete industry is crucial to meet climate change targets by 2050. To mitigate greenhouse gas (GHG) emissions from... https://escholarship.org/uc/item/5sr1v7rg Mon, 9 Feb 2026 00:00:00 +0000 Olsson, Josefine Anna https://escholarship.org/uc/item/5r0921q5 The present work consists of two qualitative studies that examined how romantic couples co-construct their identities and wellbeing through their relationship narratives. Study 1 involved a theoretically informed inductive thematic analysis of N = 95 relationship origin stories from an age-diverse community sample of romantic couples. Study 2 included a combined inductive and deductive thematic analysis of N = 40 relationship challenge narratives from college-aged participants involved in romantic relationships. Together, these studies established the relevance of relationship identity continuity, or the level of temporal coherence between a couple’s past, present, and presumed future identities, for relationship narrative identity and couple wellbeing. The act of co-constructing narratives about relationship challenges revealed how couples established continuity in their relationship identity, often drawing on shared norms of dyadic coping (e.g., framing challenges in terms of... https://escholarship.org/uc/item/5r0921q5 Mon, 9 Feb 2026 00:00:00 +0000 Alcser-Isais, Alexa https://escholarship.org/uc/item/5fv2p82b CRISPR/Cas9 technology offers precise induction of DNA double-strand breaks (DSBs) for plant genome editing, however, the low efficiency of homologous recombination (HR) in plants limits the precision allelic replacement. This study explores whether inhibiting key DNA repair pathways-classical non-homologous end joining (c-NHEJ) and theta-mediated end joining (TMEJ/alt-NHEJ)-can promote CRISPR-induced inter-homolog HR, enabling precise genetic template-based repair of DSBs. In our study, two Chlorina1 mutant lines that present yellow color - target line and partner line- were crossed under ku70 or teb background to activate CRISPR mutagenesis. We employed phenotype scoring of F1 and F2 generations (leaf color restoration) together with Sanger sequencing to characterize mutation types and frequencies across different DNA repair-deficient and wild-type backgrounds. In ku70 or teb mutant backgrounds, the Cas9/g3Mu2 construct produced approximately 6.7% green F1 plants. The green... https://escholarship.org/uc/item/5fv2p82b Mon, 9 Feb 2026 00:00:00 +0000 Meng, Yujie https://escholarship.org/uc/item/55v7t7gt Despite proven benefits of rubberized asphalt by the state department of transportation, local governments in California have been slow to adopt this technology. This study investigates the reasons cities and counties in California are not using rubberized asphalt and provides practical guidance for implementation decisions. The primary goals of this study are: (1) to assess the current adoption patterns of rubberized asphalt by local agencies; (2) to compare the field cracking performance of rubberized asphalt materials to conventional and polymer modified asphalt materials under California climate zones and traffic levels of local government roads, considering economic and environmental implications; and (3) support local government decision-making about asphalt mixtures through a practical decision-making and implementation guideline to evaluate, select and implement materials for asphalt pavement projects. Four methods were used in the study: (1) a survey of 31 local agencies... https://escholarship.org/uc/item/55v7t7gt Mon, 9 Feb 2026 00:00:00 +0000 Mallarapu, Tanoogna https://escholarship.org/uc/item/4t7596hc Advanced ultrafast techniques, such as high-harmonic generation, X-ray free-electron lasers, attosecond streaking, and reconstruction of attosecond beating by interference of two-photon transitions interferometry, now resolve electron dynamics in the time domain, including photoionization time delays on femtosecond and attosecond scales. These electron-molecule scattering and molecular photoionization spectroscopy pose stringent demands on theory: pulses shorter than 50 attosecond carry bandwidths comparable to the ionization energies of small molecules, so ultrafast experiments almost inevitably probe the photoionization continuum. Because the emitted electron is quantum mechanically indistinguishable from the bound electrons of the residual neutral or ion, the problem is intrinsically multichannel and involves electron exchange, and its numerical difficulty grows rapidly with molecular size. Exploiting such measurements requires quantitatively accurate continuum wave functions... https://escholarship.org/uc/item/4t7596hc Mon, 9 Feb 2026 00:00:00 +0000 Liu, Yuchen https://escholarship.org/uc/item/4p22m145 This study uses ACS data from IPUMS to explore the housing conditions of settled farmworkers from 2017 to 2021. Farmworkers are identified by linking industry and occupation codes, and an income-housing cost ratio approach is used to measure housing affordability and overcrowding conditions as a measure of quality at the state, agricultural region and county levels. I find that more than half of farmworker families are rent-burdened, with 24.9 percent paying 30 to 50 percent of income on rent and 26.5 percent paying more than half. Overcrowding remains high, with 30 percent of households in the ACS and 35.1 percent in the NAWS experiencing it. Notably, families on the South Coast are experiencing the most severe overcrowding. Farmworkers face the same rental housing markets as the general population, but they pay a disproportionate share of their income on housing and live in more crowded conditions. https://escholarship.org/uc/item/4p22m145 Mon, 9 Feb 2026 00:00:00 +0000 Vivas Flores, Alexis Estefany https://escholarship.org/uc/item/4j38n3w9 Metabolomics, the comprehensive study of small molecules in biological systems, has become an indispensable tool for modern biomedical research. Unlike genomics and transcriptomics, which capture potential or regulatory information, metabolite profiles reflect the real-time biochemical activities within cells, integrating genetic, enzymatic, and environmental influences. This unique property makes metabolomics particularly powerful for investigating disease mechanisms, nutritional interventions, microbiome interactions, and environmental exposures. At the same time, the concept of the exposome— the dynamic sum of environmental influences such as diet, pollutants, and lifestyle factors—has underscored the urgent need for analytical strategies that can capture both endogenous and exogenous small molecules across diverse biological contexts. High-resolution liquid chromatography–tandem mass spectrometry (LC–MS/MS) has emerged as the principal platform for these efforts, enabling... https://escholarship.org/uc/item/4j38n3w9 Mon, 9 Feb 2026 00:00:00 +0000 Kong, Fanzhou https://escholarship.org/uc/item/4b973492 Realistic human hand movement models are necessary for analyses of natural human movement (e.g., in upper extremity rehabilitation) or integration into artificial systems (e.g., robotic hands, virtual reality models) operating as references for natural human behavior to shape human-computer interactions. Human-robot control systems (i.e. virtual reality avatars, prostheses) that demonstrate more human-like behavior often elicit a stronger sense of embodiment for the user and improved control over the robotic system. Since human hand movement is a complex system to model, analyzing its subcomponents can provide more detailed information about the system’s behavior overall. Components of human hand movement include the individual and coordinated angular trajectories of the finger joints and the inherent biological noise resulting from movement discontinuities. Current human hand movement data collection methods generally do not retain these individual components, particularly the... https://escholarship.org/uc/item/4b973492 Mon, 9 Feb 2026 00:00:00 +0000 Kumagai, Hayley Elisabeth https://escholarship.org/uc/item/42f60224 Non-digestible carbohydrates and the metabolites that are produced following their fermentation by the gut microbiome are of critical importance to health. However, significant analytical hurdles remain to correlate the structure of dietary carbohydrates (and food as a whole) to outcomes such as changes in gut microbial composition or short chain fatty acid (SCFA) levels that elucidate diet-health relationships. Structure dictates function. Hence, until the chemical structure of food is well-understood, knowledge of its function will remain obscured. The work presented in this dissertation is an endeavor towards clarifying this obscurity. Chapter 1 reviews foundational concepts that are further developed in subsequent chapters, such as carbohydrate chemistry, dietary fiber composition, short chain fatty acid analysis, and the interactions of these compounds with the gut microbiome. Chapter 2 presents a multi-glycomic platform for the analysis of food carbohydrates, that is a comprehensive... https://escholarship.org/uc/item/42f60224 Mon, 9 Feb 2026 00:00:00 +0000 Suarez, Christopher https://escholarship.org/uc/item/411032sn Hydrogen sulfide (H₂S) is a highly toxic gas that inhibits cytochrome c oxidase (COX), the terminal enzyme of the mitochondrial electron transport chain, resulting in cellular energy failure, histotoxic hypoxia, and rapid cardiovascular and respiratory collapse. Despite its forensic and occupational relevance, tissue-specific effects of H₂S remain poorly characterized, limiting the development of reliable postmortem diagnostic markers. In this study, COX activity was measured across six mouse tissues, i.e. brainstem, cerebellum, olfactory bulb, lung, diaphragm, and cardiac muscle, following graded exposures to sublethal concentrations of H₂S. Baseline activity was determined in control mice exposed to room air, and enzymatic activity was assessed using a spectrophotometric assay. Data were analyzed with one-way ANOVA and Dunnett’s post hoc test. To compare relative inhibition across tissues, data of COX activity was expressed as a percent of the relevant control. In H₂S exposed... https://escholarship.org/uc/item/411032sn Mon, 9 Feb 2026 00:00:00 +0000 Miller, Amy https://escholarship.org/uc/item/3z14699c Despite the unrivaled success of the ΛCDM model, some key questions pertaining to the nature of dark matter and dark energy remain unanswered. These questions, along with persistent tensions in parameters such as H0 and σ8 continue to challenge the model. High-resolution, low-noise measurements of CMB temperature, polarization, and lensing— together with improved inference strategies, present new opportunities to test the predictions of ΛCDM when conditioned on Planck data and to probe potential deviations from the model. These measurements extend sensitivity to smaller angular scales, which encode additional information about the growth of structure, the expansion history, and possible new physics beyond the Standard Model. In this dissertation, I extend a Bayesian inference framework, MUSE, to forecast and evaluate the cosmological constraints achievable with SPT-3G, focusing on testing predictions of the ΛCDM model. I also introduce generative modeling as a tool to accurately... https://escholarship.org/uc/item/3z14699c Mon, 9 Feb 2026 00:00:00 +0000 Prabhu Palimar, Karthik https://escholarship.org/uc/item/3tq5r31r Almond trees (Prunus dulcis) have a high potassium (K) demand, with a total of 248-388 kg K/ha allocated to fruits in high-yielding crops. Despite being an abundant element in the soil, only a small portion of the total soil K is available for plant uptake, specifically the K present as soil solution K (SSK) and exchangeable K (EK). In California, to meet the K requirements and to avoid deficiencies, almond growers rely on uniform applications of K fertilizers. However, spatial and temporal within-orchard K variability is often detected both at the soil and plant level and is not fully explained. This, combined with the absence of accurate diagnostic tools, limits our ability to manage orchard K effectively.The dissertation thesis is composed of Chapter 1 (“Understanding Complexities of Potassium Management for Sustainable Crop Production - A Comprehensive Review”), Chapter 2 (“Extent and Causes of Soil Potassium Variability in California Almond Orchards”) and Chapter 3 (“Within-orchard... https://escholarship.org/uc/item/3tq5r31r Mon, 9 Feb 2026 00:00:00 +0000 Germani, Margherita Alice https://escholarship.org/uc/item/3t12m0bf The conversion efficiency and long-term stability of modern-day silicon-based solar cells critically depend on the behavior of hydrogen within their complex, multilayered architectures. While hydrogen is essential for chemical passivation of interfaces and bulk defects, it also contributes to degradation over time through its mobility and reactivity. This dissertation presents a comprehensive multiscale modeling framework that bridges atomistic, mesoscopic, and device-level phenomena to elucidate the mechanisms by which hydrogen governs the enhancement and deterioration of the passivating contacts in crystalline silicon photovoltaics. By integrating molecular dynamics, density functional theory, and kinetic modeling, this work reveals how structural disorder, carrier injection as well as cell design collectively influence hydrogen transport and defect generation. These insights advance the theoretical understanding of hydrogen-induced degradation and provide quantitative tools... https://escholarship.org/uc/item/3t12m0bf Mon, 9 Feb 2026 00:00:00 +0000 Zhao, Zitong https://escholarship.org/uc/item/3pq6z67p This exploratory research seeks to understand how the desistance process is impacted by mobility for returning citizens. Despite extensive research on the separate themes of reentry, desistance, transportation, and mobility examined in this study, few studies intersect across these themes. This study, consisting of a systematic literature review and in-depth semi-structured interviews, will bridge gaps in existing knowledge to advance studies on desistance and mobility as key to reentry, reintegration, and rehabilitation. Guided by desistance and mobility justice theoretical frameworks, this study analyzes reentry expectations and requirements, examines access to services and resources that satisfy them, and interrogates public safety metrics. Findings indicate that the complex landscape of reentry and immobility, including stigma and compounding barriers, exacerbate returning citizens vulnerabilities and hinder desirable reentry outcomes. The results suggest that mobility justice... https://escholarship.org/uc/item/3pq6z67p Mon, 9 Feb 2026 00:00:00 +0000 Herda, Socorro del Carmen Sanchez https://escholarship.org/uc/item/35b292d6 Esta disertación investiga el evangelicalismo en artefactos culturales publicados entre los años 1990 y 2023 en el Cono Sur (Argentina, Brasil y Chile) y lee su emergencia en tanto formación afectiva, es decir, como un conjunto de técnicas sensoriales y relacionales —voz, testimonio, música, tacto— que enlazan cuerpos con proyectos colectivos e imaginarios políticos. Desde esta perspectiva, la ciudadanía afectiva designa una movilización pautada de vergüenza, esperanza, dignidad, cinismo y melancolía que articula micro-rituales con macro-lógicas como la tercerización del bienestar, la racionalidad gubernamental de la seguridad y la visibilidad mediatizada.Para fundamentar esta apuesta, integro un repertorio plural de teorías del afecto y sus distintas escalas: lo corpóreo/psicofisiológico y fenomenológico del sentir; lo relacional e intersubjetivo (apegos, vergüenza, esperanza, dignidad); lo mediático y estético (circulación, performance, visibilidad); y lo gubernamental y político... https://escholarship.org/uc/item/35b292d6 Mon, 9 Feb 2026 00:00:00 +0000 Peralta Gutierrez, Jonathan Jeremias https://escholarship.org/uc/item/2mg41188 Modern mathematical practice is often informed by computational methods, and conversely, improvements in computational methods can be informed by mathematics. In this thesis we pull on these rich threads and present an interdisciplinary research program which begins with the mathematical analysis of shock formation for the fractal Burgers equation and culminates in applying intuitions gleaned from our research program on fluid mechanics to improve the statistical efficiency of multi-modal large language models.We begin with a problem from pure analysis in Chapter 2: constructing and precisely describing the shock formation process for the fractal Burgers equation. Solving this problem requires extending existing theory to cover fractional dissipation. Our result is the first to successfully deal with the fractional dissipation term through a careful pointwise analysis of the fractional Laplacian.During the completion of this first result, we made frequent use of numerical simulation... https://escholarship.org/uc/item/2mg41188 Mon, 9 Feb 2026 00:00:00 +0000 Chickering, Kyle Robert https://escholarship.org/uc/item/2kz0k6fk High school success creates pathways to higher education and upward social mobility for youth from disadvantaged backgrounds. Prior research has identified temperament and psychopathology as key predictors of school success. However, limited research examines how their development (denoted by the slope in growth curve models) through late childhood and adolescence predicts high school outcomes and educational attainment. Furthermore, despite substantial conceptual and empirical overlap between temperament and psychopathology, their shared and unique contributions to academic success remain poorly understood. This dissertation addresses these gaps through two studies using multimethod data from the California Families Project, an 18-year longitudinal study of 674 Mexican-origin youth. School outcome data come from the California Department of Education. I used latent growth curve modeling in both studies. In Chapter 1, I modelled the trajectories of temperament domains and facets.... https://escholarship.org/uc/item/2kz0k6fk Mon, 9 Feb 2026 00:00:00 +0000 Cheng, Rongxin https://escholarship.org/uc/item/2bg0j8s5 In real-world software engineering tasks, solving a problem often requires understanding and modifying multiple functions, classes, and files across a large codebase. Therefore, on the repository level, it is crucial to extract the relevant information to achieve accurate code completion effectively. Existing code completion tools have achieved some success, but they struggle to optimize the retrieval and generation process dynamically. In the thesis, we propose RepoGenReflex, a generic, dynamic, effective framework to address this challenge. By leveraging the Retrieval-Augmented Generation (RAG) enhanced with Verbal Reinforcement Learning (VRL), it can dynamically choose the optimal results for repository-level code completion. RepoGenReflex uses Reflector to give directional feedback to the next loop. RepoGenReflex chooses the optimal results stored in the Experience cache based on the RAG-VRL loop. To validate the framework’s generalization ability, we propose a new benchmark... https://escholarship.org/uc/item/2bg0j8s5 Mon, 9 Feb 2026 00:00:00 +0000 Wang, Jicheng https://escholarship.org/uc/item/2978v2dt The rates and mechanisms of binding phase precipitation fundamentally control microstructural and property development in cementitious materials such as magnesium-silicate-hydrate (M-S-H). Magnesium-based cement have shown environmental benefits with lower CO2 emissions, while providing reliable durability, strength development, and resistance to acidic conditions compared to traditional Portland cement. The growth rates and transformation pathways are fundamental processes that directly govern the material’s overall performance; however, they remain poorly understood for magnesium-based cement, limiting the ability to optimize and prevent structural failure. In this study, M-S-H was grown on freshly cleaved magnesium oxide (MgO) (100) substrates using magnesium nitrate hexahydrate and sodium metasilicate pentahydrate stock solutions to generate growth solutions containing [Mg] = [Si] = 0.4 to 30 mM. A high-resolution atomic force microscopy (AFM)-based approach was developed... https://escholarship.org/uc/item/2978v2dt Mon, 9 Feb 2026 00:00:00 +0000 Chang, Carey https://escholarship.org/uc/item/1x83p1cm The journey from mamá to presidenta is not forged alone; it is built on the foundations of familial capital, cultural values, and the resilience carried across generations. Latina university presidents remain significantly underrepresented across American higher education, yet limited research exists on the familial, cultural, and gendered influences that shape their ascent. This study explores how familial capital – the resources, resilience, and cultural expectations rooted in family – influences the leadership journeys of Latina administrators who are also mothers.The purpose of this qualitative study was to examine the intersection of motherhood, cultural identity, gender roles, and leadership among Latina university administrators. Utilizing semi-structured interviews, I engaged with four Latina executive-level administrators, including two university presidents, to capture the lived experiences, narratives, and familial dynamics that contributed to their professional rise.... https://escholarship.org/uc/item/1x83p1cm Mon, 9 Feb 2026 00:00:00 +0000 Armedilla, Danielle https://escholarship.org/uc/item/1c96p3rh This dissertation explores the complexities of identity, the home, and resilience within the Filipinx/a/o diaspora in California during the profound disruption of the COVID-19 pandemic. The study addresses a critical gap in understanding how communities of color, facing compounded health, economic, and psychological stressors, navigate a period of unprecedented crisis. Methodologically, this research moves beyond traditional, extractive paradigms by documenting and employing the kuwentuhan – a culturally-grounded practice of “talk story” integral to Filipinx/a/o culture. The findings offer three key contributions. Theoretically, the study redefines resilience not as an individual trait, but as a creative community practice. It argues that when physical households fail to provide safety and solace, shared cultural identity functions as a powerful, collective resource that helps people forge metaphorical homes built on solidarity and joy. This challenges the notion of the home as... https://escholarship.org/uc/item/1c96p3rh Mon, 9 Feb 2026 00:00:00 +0000 Taggueg, Roy Jr. Brillantes https://escholarship.org/uc/item/11j453jg California's San Joaquin Valley produces over 70% of the world's almonds but faces intensifying water scarcity and climate pressures. Cover cropping offers potential benefits for soil health and orchard resilience, yet effects on soil thermal and moisture dynamics remain poorly understood in perennial systems. This study examined how cover crops modify soil thermal regimes through multi-year observations across four paired almond orchard sites (bare soil and cover cropped) in the San Joaquin Valley.Apparent thermal diffusivity showed bare soil sites consistently exceeded cover cropped sites, though confounding soil texture differences prevented definitive attribution to cover crop management. Annual temperature damping depths were consistently shallower under cover crops (213-223 cm versus 242-249 cm), indicating reduced penetration of seasonal temperature signals. Seasonal responses of temperature and moisture varied substantially between site pairs. At Gustine, cover crops cooled... https://escholarship.org/uc/item/11j453jg Mon, 9 Feb 2026 00:00:00 +0000 McDonald, Ian Flynn https://escholarship.org/uc/item/0p89z8mq The 2022 National Roadway Safety Strategy (NRSS) introduced the Safe System approach as a new paradigm for U.S. transportation safety, aiming to eliminate traffic fatalities and serious injuries. Founded on the core principle of human fallibility, the Safe System approach shifts the focus from attributing traffic crashes to human failures to emphasize system responsibility, root causes, the prioritization of marginalized groups, and equity in policy implementation. Despite the Safe System approach’s promise of delivering more equitable outcomes, empirical research is needed to identify the populations experiencing disparities and the places where targeted interventions are most effective.In response to this research need, this dissertation, using the state of California as the study area, investigates disparities in safety interventions and crash outcomes across three focused areas: Police Enforcement (Chapter 2), Human Error (Chapter 3), and Rural Transportation Safety (Chapter... https://escholarship.org/uc/item/0p89z8mq Mon, 9 Feb 2026 00:00:00 +0000 Wang, Weijing https://escholarship.org/uc/item/0d77s0dd Estimating the time since deposition (TSD) of bloodstains is challenging due to environmental and substrate-specific factors that influence chemical degradation. This study used untargeted LC-MS/MS metabolomics to evaluate how surface type—carpet, T-shirt fabric, and blood-only controls—affects metabolite changes in drying blood pools over 21 days. After SERRF normalization and data cleaning, linear regression and ANOVA/Tukey testing identified 19 metabolites that changed significantly over time and differed between surfaces. PCA showed clear separation among the three surfaces, indicating that microenvironments created by porous materials alter metabolite stability and aging trajectories. Despite limitations, including uncontrolled temperature/humidity and analysis restricted to HILIC-positive data, the findings demonstrate that surface type significantly influences bloodstain metabolomics and should be incorporated into future TSD biomarker validation. This work contributes... https://escholarship.org/uc/item/0d77s0dd Mon, 9 Feb 2026 00:00:00 +0000 McLevis, Baylee M https://escholarship.org/uc/item/9n68c5ts Managed aquifer recharge (MAR), an increasingly important strategy for addressing groundwater depletion, can alter subsurface redox conditions in response to the infiltration of oxygenated surface water, impacting contaminant transport and microbial activity. Therefore, predicting oxidation–reduction potential (ORP) dynamics is crucial for assessing water quality risks and optimizing MAR operations. In this study, we developed a Random Forest framework to predict ORP in shallow soils subjected to flood-MAR using a comprehensive dataset from three monitoring profiles at a farm (Terranova Ranch) in California’s Central Valley, with 10-minute resolution over a monitoring period of 9–37 months, as described in (Zhou et al., 2024). Six environmental predictors—oxygen content, water saturation, temperature, depth, USDA soil texture class, and the rate of soil moisture change—were considered. The model was systematically optimized using random state selection to identify the most stable... https://escholarship.org/uc/item/9n68c5ts Sat, 7 Feb 2026 00:00:00 +0000 Zhao, Zhe https://escholarship.org/uc/item/9851c3mx The increasing occurrence of wildfire events in and around wine regions has led to abundant concerns regarding smoke affectation and smoke taint in wines made from grapes that have come into contact with smoke from these fires. Smoke affectation and smoke taint are sensory characteristics imbued to the wine from certain volatile phenol (VP) compounds and their precursors (VPP’s). This paper discusses two experiments that sought to evaluate smoke-affected wine’s impact on cooperage used for aging, the ability of common cleaning techniques to eliminate smoke taint volatile phenol (STVP) compounds and their precursors from cooperage, and whether or not cooperage that had undergone the most effective cleaning method could pass on STVP markers and their precursors to future wines aged in that same barrel. The first of these experiments, performed on American oak blocks that had been soaked in smoke-tainted wine for 6 weeks, found that steam and vacuum treatment were most effective... https://escholarship.org/uc/item/9851c3mx Sat, 7 Feb 2026 00:00:00 +0000 Swanson, Erik Jon https://escholarship.org/uc/item/95p4s3nk This dissertation utilizes plática methodology (Fierros & Delgado Bernal, 2016) to explore how Women of Color who work in informal science education (ISE) organizations—such as science centers and museums—conceptualize and experience belonging. Belonging remains a construct of high interest in education, including ISE, as leaders and practitioners grapple with transforming organizational conditions to be equitable for staff facing systematic oppression, including women, people of color, and LGBTQIA2+ individuals.To date, much of the belonging scholarship, particularly in education or organizational contexts, has been guided by Maslow’s Hierarchy of Needs (1970), which positions belonging as a fundamental human need leading to self-actualization. Across different contexts, scholars draw on this theory to explore how conditions promote a sense of connectedness to a particular community (Strayhorn, 2008, Hurtado & Carter, 1997; Slaavik & Slaavik, 2011; Pesonen et al.,... https://escholarship.org/uc/item/95p4s3nk Sat, 7 Feb 2026 00:00:00 +0000 Romero, Valeria Fike https://escholarship.org/uc/item/93j0b248 The human brain does not work in isolation, but rather bi-directionally communicates with the rest of the body through hemodynamics and the autonomic system. Despite this complexity, many studies of neurological conditions focus solely on neuronal differences and rarely consider how neuronal activity may be affected by changes in hemodynamics or systemic physiology. Understanding these interactions is especially important when investigating populations with systemic changes, such as aging or neurodevelopment, where there may be differences at multiple levels of cerebral physiology. Functional magnetic resonance imaging (fMRI) is widely used to investigate brain function and its relationship to cognition in a variety of neurological conditions. The blood oxygen level dependent (BOLD) signal of fMRI detects changes in oxygenated blood flow to indirectly measure neuronal activity, since neuronal activation is tightly linked to cerebral blood flow through neurovascular coupling. Thus,... https://escholarship.org/uc/item/93j0b248 Sat, 7 Feb 2026 00:00:00 +0000 Lee, Quimby Nicole https://escholarship.org/uc/item/92v1v7vn Improved models of triaminotrinitrobenzene (TATB)-based plastic bonded explosives (PBXs) are essential for maintaining and improving several of the most important insensitive high explosive (IHE) formulations. Towards this goal, modeling the TATB – binder interface is an active research focus because it governs many material properties of TATB-based PBXs, especially its resistance to thermal aging. Thus, this dissertation focuses on characterizing the interface between TATB and its most common binder, Kel-F 800, in order to improve modelling of the IHE PBX 9502.This dissertation reports the fabrication and characterization of a new thin film, model TATB sample to enable measurements of this interface. The films are good analogs of the TATB crystals found within PBX 9502 and can be directly deposited on Kel-F 800 thin films, forming layered PBX 9502 model samples. Neutron reflectometry measurements of the PBX 9502 model samples showed increasing roughness of the TATB – Kel-F 800... https://escholarship.org/uc/item/92v1v7vn Sat, 7 Feb 2026 00:00:00 +0000 Bull, Michael R https://escholarship.org/uc/item/90x1x005 The COVID-19 pandemic led to worldwide disruptions in learning and student engagement due to extended and widespread school closures. Following these closures, attendance rates declined, and chronic absenteeism rates rose precipitously. Attendance rates have remained below, and chronic absenteeism rates have remained above pre-pandemic levels since. California, with its heavy reliance on student attendance for funding, compulsory education requirements, and accountability compliance, as well as a history of persistent emergency-related school closures, is uniquely affected by increases in absenteeism. California has adopted multiple policy solutions to mitigate the fiscal impact of the attendance loss. All one-time changes and adjustments have run their course by the 2025-26 school year. The policy solutions that remain in effect are those that were permanent, ongoing changes to funding formulas and instructional delivery models, and newly enacted ongoing programs.Many factors... https://escholarship.org/uc/item/90x1x005 Sat, 7 Feb 2026 00:00:00 +0000 McCaskill, Wendi https://escholarship.org/uc/item/8q5037s8 This dissertation questions the anthropocentric practices embedded in filmmaking by considering the vibrancy of other-than-human matter, which are to be considered equals to human actors. The conceptual framework deployed to question this ongoing filmmaking practice is based on two pillars, one conceptual and one practical: diffraction methodologies as developed by Karen Barad and A.M. Baggs audiovisual work, particularly In My Language (2007). Rather than analyzing Baggs’s work solely through disability or media studies, the dissertation situates them within a broader posthumanist and Feminist STS framework that prioritizes relationality, difference and nonhuman co-agency.Whereas Baggs’ work challenges normative subjecthood and language, the reframing of this dissertation insists that these questionings have ontological, aesthetic, and political implications. These questionings echo those of Barad’s diffraction/difference, as a method of perception that resists mirroring and instead... https://escholarship.org/uc/item/8q5037s8 Sat, 7 Feb 2026 00:00:00 +0000 Gatto, Julian https://escholarship.org/uc/item/8pc4d2gc Extracellular vesicles (EVs) are increasingly recognized as adaptable vehicles for RNA therapeutics and gene-editing materials; however, achieving high cargo loading that translates into reliable protein expression poses a significant challenge, especially in clinically promising yet technically difficult sources like placental mesenchymal stem/stromal cell-derived EVs (PMSC-EVs). This thesis methodically examined the exogenous loading of mRNA into PMSC-EVs by both physical and chemical methodologies. A dual-reporter Cy5-EGFP mRNA construct was utilized to measure loading (Cy5-positive cells) and functional translation (GFP-positive cells) in a single test. Cholesterol-modulating, physical loading with MβCD-assisted treatment significantly elevated Cy5 signal while producing negligible GFP, suggesting improved apparent cargo attachment without effective cytosolic release or translation. Conversely, chemical loading resulted in enhanced vesicle encapsulation with functional mRNA... https://escholarship.org/uc/item/8pc4d2gc Sat, 7 Feb 2026 00:00:00 +0000 Maisuriya, Isha Sanjaykumar https://escholarship.org/uc/item/8f66853t Urban grazing, also known as city grazing, offers a creative and eco-friendly way to manage urban landscapes. Historically, livestock played an essential role in urban life, and reviving these practices today offers opportunities to reconnect people with nature, enhance mental well-being, and address environmental challenges. While the ecological impacts of urban grazing, such as vegetation management, improving biodiversity, and wildfire risk reduction, are well documented, its social and cultural dimensions remain underexplored. This research highlights the potential of urban grazing to become a meaningful part of land management in cities, offering spaces where people can connect with each other, engage with animals, and contribute to environmental solutions. By bridging ecological goals with community needs, this study aims to offer practical recommendations for designing urban grazing spaces that improve both sustainability and stronger social ties. Using the UC Davis Sheepmowers... https://escholarship.org/uc/item/8f66853t Sat, 7 Feb 2026 00:00:00 +0000 sadeghmalakabadi, sahar https://escholarship.org/uc/item/8b81x9nr Endothall (7-oxabicyclo[2.2.1]heptane-2,3-dicarboxylic acid) is widely used as an aquatic herbicide to control submerged aquatic weeds. Two formulations of endothall are registered for application in irrigation canals: the dipotassium salt (Cascade®) and the mono (N,N-dimethylalkylamine) salt (Teton®). To address grower concerns that endothall-treated irrigation water could have phytotoxic effects on California crops, experiments were conducted in the greenhouse in 2023 and in the field in 2023 and 2024 at UC Davis to characterize potential phytotoxicity. Concentrations used in the experiments were selected referencing the maximum application rate of endothall of 5 parts per million active ingredient (ppm ai) within a seven-day window for use in irrigation canals. The label for the dipotassium formulation of endothall lists the chemical in ppm ai while the label for the monoamine endothall lists the chemical in parts per million acid equivalent (ppm ae). In the greenhouse studies,... https://escholarship.org/uc/item/8b81x9nr Sat, 7 Feb 2026 00:00:00 +0000 Chang, Stephen Chiyao https://escholarship.org/uc/item/8967b9cb This study presents a workflow for structural sizing and flutter analysis of lifting surfaces, integrating finite element modeling, strength and stability sizing, and aeroelastic assessment within a unified process. The approach couples the solutions from a finite element solver, NASTRAN, (static loads, modal analysis, and flutter prediction) with the iterative sizing capabilities of a software called HyperX through their sizing optimization feature, HyperFEA. The methodology is applied to a general aviation–class blended wing body (BWB) aircraft to evaluate the effectiveness of the process across multiple internal wing layouts. Two structurally distinct configurations were developed and sized to satisfy all static strength and stability requirements. Subsequent flutter analyses revealed aeroelastic instabilities that were corrected through targeted stiffness constraints applied in HyperX's cross-section tool. The resulting stiffness adjustments successfully eliminated flutter... https://escholarship.org/uc/item/8967b9cb Sat, 7 Feb 2026 00:00:00 +0000 Buddhamatya, Napsia https://escholarship.org/uc/item/8587219g The COVID-19 pandemic caused unprecedented disruptions to K-12 education, including prolonged school closures, leading to significant learning loss and intensifying the need to identify key factors that accelerate student academic recovery. This unique post-closure environment presented a critical opportunity to re-examine the relationship between teacher experience and student achievement. Guided by human capital theory, this study investigated whether traditional indicators of teacher quality predicted student outcomes amid the new challenges faced by educators and students. This study employed a Hierarchical Linear Model (HLM) to analyze i-Ready assessment data in English Language Arts (ELA) and Mathematics for K-2 students from the 2022-2023 and 2023-2024 academic years in one California district. The analysis controlled for student-level variables while examining teacher-level predictors. Findings indicated that years of teaching experience and credential type (Preliminary... https://escholarship.org/uc/item/8587219g Sat, 7 Feb 2026 00:00:00 +0000 Sekhon, Kuljinder https://escholarship.org/uc/item/8382v6h8 Commercial Low Earth Orbit (LEO) satellite deployments have emerged as a viable solution towards ubiquitous global coverage and high-throughput connectivity. Satellite-based Non-terrestrial Networks (NTN) are envisioned to bring network coverage to remote and underserved regions, additionally supporting and enhancing service provided by current terrestrial networks. 3GPP's NTN initiatives are to ensure service continuity, service ubiquity, and service scalability. Despite this, NTN systems, especially satellite-based based face many challenges. Beyond the cost of launch and deployment, LEO satellite systems often suffer from low signal power, nonuniform beam coverage, co-channel and inter-channel interference, and limited spectral resources. In this work, we propose novel methodologies to address these challenges of LEO-satellite-based NTN systems. We begin by formulating the LEO-satellite user association problem as a multi-user multiple-input-multiple-output (MU-MIMO) satellite... https://escholarship.org/uc/item/8382v6h8 Sat, 7 Feb 2026 00:00:00 +0000 Bhattacharyya, Arindam https://escholarship.org/uc/item/7xj8t7p5 The ability to recode RNA molecules directly has transformed our understanding of how genetic information can be manipulated and repaired. Adenosine deaminases acting on RNA (ADARs) catalyze the site-selective deamination of adenosine to inosine (A-to-I) within double-stranded RNA, a modification that alters the informational content and function of the target transcript. Inosine base pairs with cytidine and is read as guanosine, allowing this reaction to enable precise single-nucleotide recoding of RNA. Harnessing this chemistry has led to the development of site-directed RNA editing (SDRE), a programmable platform that corrects pathogenic G>A mutations through ADAR-mediated deamination, providing an alternative to permanent DNA editing strategies.Despite its promise, achieving efficient and specific ADAR editing across diverse sequence contexts remains challenging. The outcome of an editing reaction depends on subtle features of the guide-target duplex, including local sequence... https://escholarship.org/uc/item/7xj8t7p5 Sat, 7 Feb 2026 00:00:00 +0000 Salvador, Prince Jarmycko https://escholarship.org/uc/item/7xf0x9c9 Education plays a central role in shaping human development, social mobility, and economic growth. Beyond providing skills for the labor market, it expands opportunities, fosters agency, and enables individuals to participate fully in society. Yet despite its transformative potential, higher education remains characterized by persistent inequities, whether in access to fields of study, representation across gender and social groups, or the learning environments that students encounter. This thesis contributes to the understanding of how education policies and practices influence both access and outcomes, focusing on two distinct contexts: Uganda and the United States. By examining large-scale institutional reforms as well as classroom-level interventions, it highlights how policy choices can alter behavior, reshape opportunities, and generate broader spillover effects that extend beyond targeted groups. The first essay investigates a gender-based affirmative action policy... https://escholarship.org/uc/item/7xf0x9c9 Sat, 7 Feb 2026 00:00:00 +0000 Chopra, Saloni https://escholarship.org/uc/item/7x52q7pd This dissertation focuses on the management of water scarcity in two settings: the irrigated agriculture response to drought and the public participation in groundwater management. A common thread in the analysis is the use of modern tools, including artificial intelligence to access large volumes of previously unavailable data. I combine empirical analysis with the AI-assisted methods to gain new insights into how societies adapt to increasing water stress.Irrigated regions are becoming increasingly vulnerable to water stress. In the first essay, I examine how fluctuations in reservoir storage affect irrigated agriculture in the Western United States from 2008-2020. I leverage a large language model (LLM) Claude 3.5 Sonnet to link 287 reservoirs to 202 counties, and pair this with county-level panel of weather and drought indices. Using a panel fixed effects regression, I analyze how changes in reservoir storage affect key agricultural outcomes along two margins: fallow acreage... https://escholarship.org/uc/item/7x52q7pd Sat, 7 Feb 2026 00:00:00 +0000 Jezdimirovic, Jelena https://escholarship.org/uc/item/7vv0w22q Abstract interpretation provides a general framework for expressing static program analyses by reducing the task of inferring program invariants to computing an approximation of the least fixpoint of a system of equations. A commonly used approach for this computation is Bourdoncle’s sequential iteration strategy, which relies on a weak topological order (WTO). This thesis addresses the challenge of improving the computational efficiency of abstract interpretation while maintaining precision of its analyses. It introduces a novel method for deterministically parallelizing Bourdoncle’s iteration strategy by leveraging the concept of a weak partial order (WPO). Additionally, it proposes an optimal approach to minimize the memory footprint of the sequential iteration strategy, ensuring the same results are computed with the least possible memory usage. Notably, the techniques presented are abstract domain-agnostic, making them broadly applicable across various analysis scenarios. ... https://escholarship.org/uc/item/7vv0w22q Sat, 7 Feb 2026 00:00:00 +0000 Kim, Sungkook https://escholarship.org/uc/item/7sd0p117 R-loops are three-stranded nucleic acid structures formed during transcription when the nascent RNA hybridizes to the template DNA strand, displacing the nontemplate strand. These structures play complex roles in cellular processes, ranging from physiological functions such as class switch recombination and transcription termination to pathological contributions to genomic instability and disease. Despite growing recognition of their biological importance and their implication in a wide range of cellular phenomena, fundamental questions remain about the factors governing R-loop formation, stability, and distribution. This dissertation investigates how DNA sequence, topology, and nontemplate strand factors collectively shape the R-loop landscape using in vitro transcription systems coupled with single-molecule R-loop footprinting (SMRF-seq). To systematically evaluate sequence contributions, we designed and characterized a library of 31 plasmids containing 200 bp variable... https://escholarship.org/uc/item/7sd0p117 Sat, 7 Feb 2026 00:00:00 +0000 Holleman, Ethan Thomas https://escholarship.org/uc/item/7dm0n063 In modern computing systems data movement now dominates energy consumption, and interconnect bandwidth has become the primary bottleneck limiting system performance. Compute demands for machine learning and generative AI applications - from petaFLOPs in 2010 to projected quettaFLOPs by 2030 - have exposed fundamental limitations in copper-based electrical interconnects: signal integrity degradation at high data rates, shoreline-limited I/O density in 2D/2.5D packaging, and poor energy scaling with interconnect length. This dissertation proposes and develops a 3D integrated electronic-photonic interconnect (EPIC) platform for chiplet stacks that addresses these scalability challenges by moving highspeed data communication to the optical domain, while retaining electrical interconnects for power delivery and short-reach low-latency communications.We develop a unified benchmarking framework for evaluating interconnect performance through fundamental metrics: energy efficiency, bandwidth... https://escholarship.org/uc/item/7dm0n063 Sat, 7 Feb 2026 00:00:00 +0000 Samanta, Anirban