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The State of Zero-Emissions Delivery in the U.S.
Get PDFWe have seen major changes in the last few years as cities and companies in the United States transition to more environmentally sustainable urban delivery. But progress still remains piecemeal and slow. In both policy and practice on city streets, Europe and parts of Asia are far ahead of the U.S. in advancing electrification, shifting away from traditional trucks to smaller forms like e-bikes, and managing city space to induce or support zero emission delivery (ZED).
This paper captures the state of policy and practice of zero emission delivery in the U.S. as of January 2025. It offers a baseline for future work and surfaces levers U.S. cities can consider using to advance ZED. In this report, researchers from the Urban Freight Lab at the University of Washington created a policy and practice framework based on their expertise, review and synthesis of academic literature, current technology and private sector achievements. Via the framework, the research team identifies a three-legged stool of approaches needed to achieve or advance zero emission delivery in the United States.
These three vital areas for progress on ZED are:
Electrification
Mode Shift and Behavior Change, and
Real Estate and Space Management
For some, these three key building blocks and the myriad elements discussed in this report may not have been linked as levers to catalyze ZED.
The report is divided into three sections, one for each of the key areas above. Each area has an overview of the current state of practice and associated trends, followed by both public sector-led and private-sector-led examples of the approach under discussion. All examples focus on real-world implementation (both domestic and international), showcasing ZED and/or providing a realistic pathway to advance ZED. And all examples focus a lens squarely on cities.
In the process of compiling this summary of the state of practice of ZED, the research team synthesized key takeaways for cities to consider in Electrification, Mode Shift and Behavior Change, and Real Estate and Space Management
Neighborhood Green Space and Objective Measures of Sleep: The Multi-Ethnic Study of Atherosclerosis (MESA) Sleep and MESA-Air
Get PDFThesis (Master's)--University of Washington, 2025Background: Sleep-disordered breathing (SDB), including obstructive sleep apnea (OSA), is a prevalent and underdiagnosed condition with significant health and economic consequences. While individual behaviors and environmental exposures are known contributors to poor sleep, the role of neighborhood green space remains underexplored, particularly using objective sleep measures. Methods: This study investigates the association between residential greenness—measured by the Normalized Difference Vegetation Index (NDVI)—and polysomnography (PSG)-measured sleep outcomes in 1,543 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) Sleep Ancillary Study. NDVI was assessed within 30m and 300m buffers around participants' homes to capture immediate environmental and neighborhood-scale exposures, respectively. The primary outcome was moderate to severe OSA (AHI ≥15 events/hour), with secondary outcomes including wake after sleep onset (WASO), proportion of sleep time when arterial oxygen saturation (SaO2) falls below 90% (T90), nadir oxygen saturation (SpO2), and oxygen desaturation index (4% desaturation) events per hour. Results: Fully adjusted models revealed that a one interquartile range increase in annual NDVI within a 300m buffer was associated with a 19% lower prevalence of moderate to severe OSA (PR = 0.81; 95% CI: 0.68, 0.98). Associations at smaller buffer sizes were directionally consistent but not statistically significant. No significant associations were observed for secondary sleep outcomes. Conclusion: These findings suggest that neighborhood-scale greenness may reduce the risk of sleep apnea, potentially through mechanisms involving increased physical activity and reduced environmental stressors. This study underscores the importance of considering spatial scale in sleep and environmental health research and supports the integration of green infrastructure into urban planning to promote sleep health
Transcriptomic Analysis Reveals Metabolic and Epigenomic Reprogramming During Lytic Phase of MHV-68 Infection
Get PDFThesis (Ph.D.)--University of Washington, 2025The human gammaherpesviruses (γHV) Kaposi Sarcoma-Associated Virus (KSHV) and Epstein Barr Virus (EBV) are two of the seven known human oncogenic viruses. KSHV infects around 5% of the population and causes cancers such as Kaposi Sarcoma in immunodeficient individuals, whereas EBV infects >90% of the population and is linked to lymphomas and, more recently, multiple sclerosis. Despite their impact on human health, there are currently no drugs to treat either virus. This may in part be due to difficulties studying the lytic phase in the human γHVs; KSHV and EBV both immediately enter latency upon initial infection. A better understanding of what processes occur during the lytic phase, the part of the viral lifecycle during which the virus actively replicates, may offer new insights on potentially druggable pathways. MHV-68 is a murine γHV that immediately enters the lytic phase upon primary infection and shares ~80% sequence similarity with the human γHVs, thus making it a good model for studying the lytic phase in the human γHVs. Surprisingly, there have been no prior studies of the host transcriptome during viral infection of NIH3T3 cells, one of the most common models for the study of MHV-68. In this body of work, I analyze bulk RNA-seq data from MHV-68 infected NIH3T3 cells with the goal of identifying potential druggable pathway(s). In taking a two-pronged approach in which I assess the most differentially expressed metabolic and epigenomic genes/pathways, I present transcriptomic evidence for increased redox stress in MHV-68 infected NIH3T3 cells, as well as evidence for perturbations in chromatin biology. My analysis indicated an increase in transcripts encoding components of the mitochondrial electron transport chain, glutathione synthesis, and NADPH-producing pathways, collectively suggesting increased oxidative stress over the course of infection. Notable changes in chromatin biology include upregulation of the expression of DNA demethylases and the DNA damage response chaperone DAXX. Additionally, canonical histone H2A was upregulated, while histone variant H2AX was downregulated late in lytic infection. Ultimately, I found that inhibition of the DNA demethylating enzymes Ten-eleven translocase 1 and 2 (Tet1 and Tet2) diminishes MHV-68 replication in this system. The mechanism behind how Tet1/2 inhibition reduces viral titer remains to be explored
Advancing PrEP Use among Pregnant Women in sub-Saharan Africa
No full textThesis (Ph.D.)--University of Washington, 2025In sub-Saharan Africa (SSA), cisgender women are disproportionately affected by HIV, accounting for approximately 63% of all new infections in this region. Pregnancy, a period experienced by many young women in SSA, is associated with an elevated risk of HIV acquisition due to the combined effects of behavioral, immunological, and hormonal changes. Daily oral tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) pre-exposure prophylaxis (PrEP) is highly effective in decreasing HIV acquisition risk when taken as prescribed and is recommended by the World Health Organization (WHO) as one of the prevention options for individuals at substantial HIV risk, including cisgender women. However, additional questions on intracellular exposure in HIV target cells during pregnancy and the long-term growth and bone health outcomes for infants with utero TDF/FTC PrEP, remain unanswered.The adherence–concentration–efficacy relationship for TDF/FTC PrEP has been well established among gay, bisexual, and other men who have sex with men (MSM), indicating that taking four doses/week can reduce HIV acquisition risk by approximately 96%. However, this relationship has been less studied in cisgender women, leading to uncertainty about optimal dosing strategies in this population. Based on pharmacologic evidence showing lower drug penetration in female genital track compared to rectal tissue, cisgender women have been advised to take one pill daily to achieve levels of protection similar to those observed in MSM taking four doses/week. This messaging may pose substantial barriers to PrEP initiation and continuation in cisgender women. Additionally, pregnancy is associated with profound physiological changes that may lead to suboptimal drug exposure, reduced efficacy, and uncertainty regarding optimal PrEP dosing strategies for HIV prevention in this critical period. Several studies have reported decreased concentrations of tenofovir diphosphate (TFV-DP), the active metabolite of TDF, in red blood cells measured using dried blood spots (DBS) during pregnancy; however, changes in drug concentrations at clinically relevant sites for HIV prevention remain less understood. Furthermore, while TDF is generally considered safe, its use has been associated with renal and bone toxicity. During pregnancy, tenofovir (TFV), the parent drug of TDF, readily crosses the placenta and may potentially affect fetal bone development. However, few studies have evaluated the impact of maternal TDF exposure on children bone health, and the findings have been mixed. Additional data are needed to determine whether and to what extent in-utero TDF exposure affect bone outcomes in children.
The studies presented in this dissertation address these key knowledge gaps to inform the effective and safe use of oral TDF/FTC PrEP among pregnant women in SSA and has the potential to guide clinical guidelines and policy decisions to optimize PrEP delivery in this population.
In Chapter 2, we conducted a systematic review to summarize current evidence and identify knowledge gaps related to protective adherence levels of TDF-based oral PrEP in cisgender women, including during pregnancy. We found that women-specific intracellular TFV-DP adherence benchmarks in DBS and peripheral blood mononuclear cells (PBMC) fall within the range of historical U.S.-based thresholds derived from healthy men and women. Emerging evidence suggests that imperfect but adequate adherence to oral FTC/TDF PrEP with at least four doses/week provides sufficient HIV protection in cisgender women; however more data are still needed to refine the intrinsic achievable efficacy estimates for cisgender women.
In Chapter 3, we leveraged a directly observed dosing study in Kenya, in which 18 pregnant and 18 non-pregnant women received daily dosing of TDF/FTC for 8 weeks. Blood for DBS and PBMC was collected weekly for non-pregnant and bi-weekly for pregnant women. We characterized paired TFV-DP concentrations in DBS and PBMCs and quantified matrix-specific pharmacokinetic differences by pregnancy status. We found that steady-state TFV-DP concentrations from daily dosing of TDF/FTC were approximately two-fifths lower in DBS during pregnancy, whereas TFV-DP and emtricitabine triphosphate (FTC-TP) concentrations in PBMCs were not meaningfully different between pregnant and non-pregnant women. We also compared growth outcomes of infants exposed to daily dosing of TDF/FTC in pregnancy to historical TDF/FTC-unexposed infants from the placebo arm of the Partners PrEP Efficacy Study. We found Z-scores for infant weight, length, and head circumference were comparable at 6, and 12 months of age.
In Chapter 4, by leveraging a prospective cohort that evaluated the oral TDF/FTC PrEP safety in pregnant and postpartum women in Western Kenya, we conducted a matched cohort study to assess the association between in-utero PrEP exposure and bone mineral content (BMC) for whole body less head and lumbar spine at 36 and 52 months of age. We found that mean BMC for whole body less head and lumbar spine were not lower among children with in-utero PrEP exposure. While the overall prevalence of low BMC in our study population was high (20%-30%), in-utero PrEP exposure was not associated with higher prevalence of low BMC. Our findings are reassuring and support the continued use of oral TDF/FTC PrEP during pregnancy
Distributed FaaSRunner: Enabling Reproducible Multi-node, Multi-threaded Function-as-a-Service Endpoint Testing
Get PDFThesis (Master's)--University of Washington, 2025Today's cloud native applications are often built using a service-oriented architecture supported by many microservices hosted using serverless Function-as-a-Service (FaaS) platforms. The vast majority of serverless function benchmarks and tests are performed using a single-client machine to generate workloads against highly scalable serverless backends. However, single-client test engines can lack sufficient computational resources and network bandwidth to adequately stress serverless backends. Testing tools such as Apache JMeter support orchestrating tests using multiple client nodes, but lack the ability to orchestrate sophisticated tests with distributed workload patterns common with real-world serverless workloads. In this thesis, we introduce Distributed FaaSRunner, a distributed test tool which supports the ability to reproduce multi-node serverless workloads using traces derived by ingesting serverless function log files and randomly generated workload traces. We test Distributed FaaSRunner's ability to precisely reproduce serverless function request dispatch and arrival time using various test cluster configurations. Using globally distributed clients, we predict latency to adjust workload trace event dispatch times to reproduce original request arrival latency. We demonstrate that Distributed FaaSRunner can reproduce both temporal and spatial characteristics of serverless workloads, enabling new capabilities to assess performance of FaaS platforms beyond traditional load testing
Inflammation contributes to trauma-induced coagulopathy by oxidation of multiple clotting factors.
No full textTrauma-induced coagulopathy (TIC) induces anticoagulation and increases bleeding mortality. Inflammation and oxidative stress play an unknown role in TIC. We examined plasma from injured human trauma patients presenting to the Emergency Department compared to healthy controls to elucidate the contribution of inflammation and oxidative stress to anticoagulation during TIC. Trauma patients demonstrated coagulopathy by prolongation of clotting time assays and decreased thrombin generation in addition to increased pro-inflammatory cytokines and increased markers of oxidative stress. Clotting factors seven (FVII), ten (FX), and twelve (FXII) were oxidatively modified without quantitative changes, displaying decreased activity after trauma. Factor five (FV) was decreased in concentration and retained normal activity. Factor eight (FVIII) concentration and activity were increased after trauma. Clotting factor oxidation after exposure to activated human leukocytes in vitro also impaired thrombin generation and reproduced the oxidative and functional changes seen in trauma patients. Both antioxidant and anti-inflammatory treatments prevented clotting factor oxidation and TIC after trauma in vivo using a rodent TIC model. These results suggest that inflammation and oxidative stress contribute directly to anticoagulation during TIC by direct and selective oxidation of clotting factors. FXII may make a novel contribution to the pathophysiology of TIC by its oxidation
Sacrificing Futures: Campus Sexual Violence, Unmet Survivor Needs, and University Complicity
Get PDFMaster of Social Work (MSW)This PDF poster examines the needs of survivors of campus sexual assault and intimate partner violence, and potential interventions that would be supportive of the needs of survivors
Building Bridges: Empowering Latinos through student-profession Networking
Get PDFMaster of Social Work (MSW)First-generation Latino students fall short of achieving post-secondary degree attainment compared to their leading White and Asian peers, causing a long stream of effects. To address this social issue, we propose an intervention aimed at expanding college preparation resources for FGLS. Drawing on social capital and validation theory, our goal is to connect Latino students with role models they culturally identify with. This connection will help expand their knowledge of attainable occupations and provide them with critical information for successful college and career choices. Additionally, by fostering a sense of capability and self-worth, we hope students can acknowledge their inherent value
Experimental Investigation of Plasma-Electrode Interactions on the ZaP-HD Flow Z-Pinch Device
Get PDFThesis (Ph.D.)--University of Washington, 2025The electrodes of sheared-flow-stabilized (SFS) Z-pinch devices directly face the core plasma and supply the pinch current. The high temperature, high density plasma environment produces intense particle and heat fluxes, leading to concerns of electrode erosion that limit durability and contaminate the plasma. An improved understanding of these plasma-electrode interactions is required, especially at the high temperatures and current densities required for fusion applications. An experimental investigation is conducted on the ZaP-HD SFS Z-pinch device, which produces plasma temperatures up to 1 keV, densities of 10^23 m^-3, and drives pinch currents up to 150 kA. In-situ measurements of the gross carbon erosion flux from the graphite electrode are obtained with S/XB spectroscopy. The measured fluxes exceed the theoretical values from physical sputtering, but are comparable with the expected sublimation flux. An analysis of the ionization mean free paths of neutrals produced by both erosion processes indicates that ionization of sublimated carbon occurs within the electrode sheath, while sputtered neutrals are ionized outside of the sheath. This suggests significant redeposition of sublimated carbon, leading to a process of carbon recycling. The sputtered carbon is therefore primarily responsible for the net erosion. Initial measurements of the electrode surface temperature with a two-color pyrometer are also presented. Ex-situ analysis of electrode material is enabled by the design of a removable coupon. Three different plasma exposure cases were tested that involved varying the pinch current and the particle fluence to the electrode. Net mass loss measurements imply net erosion fluxes far smaller than indicated by spectroscopic measurements of total erosion, which supports the theory of high redeposition rates. Erosion rates range from 0.01 to 0.1 mg/C, which are comparable to existing arc discharge devices. Measurements of the microscopic surface morphology and roughness indicate substantial material rearrangement and general smoothing except at high plasma exposure conditions. The granular matrix of graphite is mostly replaced by larger consolidated structures that reduce the number of visible voids. Crack formation is apparent, possibly due to thermal cycling, which suggests the importance of surface heating and possible phase change of graphite. Definitive features of sputtering such as pitting and cratering are absent, and further study is needed to attribute the observed morphology to other physical processes. Overall, these results indicate some alignment with erosion and recycling processes in high-current arc discharges, which have successfully operated with solid electrodes in extreme environments. Further investigation into these similarities may yield useful understanding that can be applied to the management of erosion on SFS Z-pinch electrodes
Disobedient Robots
Get PDFThesis (Ph.D.)--University of Washington, 2025Disobedient Robots interrogates how robots can disobey their categorization as mere extensions of the human body to become bodies with agency themselves. Rooted in the notion of desobediencia tecnológica [technological disobedience], a term coined by Ernesto Oroza, the project responds to the productive and surveillance imperatives that drive most mainstream robotics, opening space for alternative forms of making, experimentation, and collaboration. It operates as both a research platform and a theoretical framework that has inspired the artworks I have created and will continue to develop.Two works, the Dispositivo de Realidad Mutada (DRM) and the AGNS Collective, serve as central expressions of this research. Emerging through recursive processes of building, failing, and reconfiguring, they explore the idea of a robotic "voice" as it unfolds through sound, movement, and collective behavior rather than anthropomorphic imitation.
The project further extends into collective practices, including the Disobedient Robots Online Platform and the II Encuentro Internacional de Robótica Artística / Desobediencias Robóticas. Taken together, these dimensions affirm robotic art as an open-ended practice for reimagining our relationships with machines