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International Journal of Applied Earth Observation and Geoinformation
No full textLand subsidence is a growing geohazard that poses a significant threat to critical infrastructure, particularly in urban coastal cities. This study uses Interferometric Synthetic Aperture Radar (InSAR) data from 2016 to 2024 to estimate angular distortion rates to assess infrastructure damage risk in New York City. We applied a probabilistic framework to evaluate multiple “what-if” scenarios and project long-term risks, providing actionable insights for resilience and mitigation planning. Results reveal persistent subsidence in low-elevation and reclaimed zones (∼-5 mm/yr) with localized uplift (∼+1.5 mm/yr), affecting major airports, subway segments, and highways. Fifty-year projections indicate high angular distortion probabilities (0.6–0.8), with economic exposure estimated at ∼10.54 billion for ∼ 7.8 km of highways exceeding –2 mm/yr. Despite their limited spatial extent, these segments represent a disproportionately large share of total exposure. The findings emphasize the need for continuous monitoring, proactive mitigation, and targeted investment, highlighting the value of integrating geodetic data with probabilistic modeling to address subsidence and climate-related hazards.Published versio
Cells
No full textVenezuelan equine encephalitis virus (VEEV) is a mosquito-borne pathogen causing low mortality but high morbidity in humans, with 4–14% cases exhibiting neurological complications. While the cyclic GMP-AMP synthase–stimulator of interferon genes (cGAS–STING) pathway is canonically associated with double-stranded DNA (dsDNA) detection, it has been shown to respond to RNA viruses and subsequently limit viral pathogenesis. Several viruses antagonize this signaling cascade, underscoring the importance that cGAS–STING plays in host immunity. Previous studies regarding single-stranded RNA viruses revealed that cGAS–STING limits viral replication in Old World alphavirus chikungunya virus infections, but little is known about New World alphaviruses such as VEEV. Here, we investigate the impact that STING activation has on VEEV infection as a potential prophylactic and therapeutic intervention. VEEV infection alone did not induce STING phosphorylation at Ser366, but interferon-stimulated genes (ISGs) were upregulated during the late phase of infection. Loss of STING through siRNA showed a partial dependency on STING for ISG transcription, suggesting that STING activation may occur through a noncanonical process. Priming of the STING pathway prior to infection was found to be critical in limiting viral replication; however, targeting STING activation post-infection abrogated the antiviral effects that dsDNA had on VEEV. VEEV suppressed STING phosphorylation in a multiplicity of infection (MOI)-dependent manner with the most robust pSTING (Ser366) inhibition observed at an MOI of 10. Collectively, our results suggest that VEEV antagonizes canonical STING activation.Published versio
Architecture and Memory at the Intersection of Transit, the Built Environment, and Placemaking in Tysons, VA
No full text"Palimpsest"
noun: palimpsest; plural noun: palimpsests
a manuscript or piece of writing material on which the original writing has been effaced to make room for later writing but of which traces remain.
something reused or altered but still bearing visible traces of its earlier form.
My thesis revolves around Tysons, VA. A census designated place located in Northern Virginia. Tysons, VA has a unique history of development, grounded in technology, infrastructure, commercial interests, and government among others. Tysons has operated as an extension of Washington, DC throughout its history, as well as a "downtown" for Fairfax County, VA. With four metro stations, plentiful office buildings, commercial real estate, and more, this area has the potential to be a unique urban/suburban conglomerate. Yet, it falls short of breaking out of its "Edge City" classification . I have come to the following critique: although Tysons boasts fascinating urban conditions, its current development structure falls short in facilitating public life for residents, commuters, visitors, passersby, etc. All aided by the overabundance of asphalt and concrete, incredibly robust traffic, and lack of pedestrian infrastructure.
I will employ the following methods for my research and to communicate my findings. My methods build upon one another, to create a body of work that is interconnected. Information is collected through archival research of Tysons, VA development history, precedent studies of public versus private spaces, and materiality studies. Observations and analysis are communicated through visual aids such as collage, sketch, and cyanotype. In addition, I use audio/visual media to communicate the multi-sensory nature of the intervention and studies.
This thesis introduces a new layer to the Tysons Urban fabric – one that is dedicated to the insertion of experiential community building, placemaking, equity, and opportunity. Through a truly public intervention, the thesis acknowledges the wonder of the urban palimpsest, and the beauty that can thus emerge in both the physical and ephemeral realm, through the intersecting layers of the built environment.
Bibliography
Oxford Dictionary. 2024. "Oxford Languages." Oxford Languages. Oxford University Press. 2024. https://languages.oup.com/google-dictionary-en/.
Garreau, Joel. 1991. Edge City : Life on the New Frontier. Toronto ; New York: Doubleday.Master of Architecture"Palimpsest"
noun: palimpsest; plural noun: palimpsests
a manuscript or piece of writing material on which the original writing has been effaced to make room for later writing but of which traces remain.
something reused or altered but still bearing visible traces of its earlier form.
My thesis revolves around Tysons, VA. A census designated place located in Northern Virginia. Tysons, VA has a unique history of development, grounded in technology, infrastructure, commercial interests, and government among others. Tysons has operated as an extension of Washington, DC throughout its history, as well as a "downtown" for Fairfax County, VA. With four metro stations, plentiful office buildings, commercial real estate, and more, this area has the potential to be a unique urban/suburban conglomerate. Yet, it falls short of breaking out of its "Edge City" classification . I have come to the following critique: although Tysons boasts fascinating urban conditions, its current development structure falls short in facilitating public life for residents, commuters, visitors, passersby, etc. All aided by the overabundance of asphalt and concrete, incredibly robust traffic, and lack of pedestrian infrastructure.
I will employ the following methods for my research and to communicate my findings. My methods build upon one another, to create a body of work that is interconnected. Information is collected through archival research of Tysons, VA development history, precedent studies of public versus private spaces, and materiality studies. Observations and analysis are communicated through visual aids such as collage, sketch, and cyanotype. In addition, I use audio/visual media to communicate the multi-sensory nature of the intervention and studies.
This thesis introduces a new layer to the Tysons Urban fabric – one that is dedicated to the insertion of experiential community building, placemaking, equity, and opportunity. Through a truly public intervention, the thesis acknowledges the wonder of the urban palimpsest, and the beauty that can thus emerge in both the physical and ephemeral realm, through the intersecting layers of the built environment.
Bibliography
Oxford Dictionary. 2024. "Oxford Languages." Oxford Languages. Oxford University Press. 2024. https://languages.oup.com/google-dictionary-en/.
Garreau, Joel. 1991. Edge City : Life on the New Frontier. Toronto ; New York: Doubleday
International Journal of Environmental Research and Public Health
No full textHousing instability, particularly frequent residential moves, has been associated with poor developmental outcomes, yet its relationship with adverse childhood experiences (ACEs) remains insufficiently understood at the national level. This study addresses this gap by investigating how frequent moves shape children’s exposure to ACEs, and whether community and household contexts influence these effects. Using the 2020–2021 National Survey of Children’s Health data, we ask two questions: (1) Do children who experience frequent moves face greater risk of ACEs? and (2) Do neighborhood and metropolitan contexts mitigate or exacerbate this association? Our contribution is twofold. First, we examine both directions of the relationship: how ACEs predict frequent moves and how frequent moves increase ACE exposure. Second, we incorporate contextual moderators, including supportive neighborhoods, safety, amenities, and urban residence, to provide a more nuanced account of how environments shape resilience or vulnerability. Using logistic and negative binomial regression models, we find that all ACEs significantly predict frequent moves, with parental divorce/separation showing the largest effect. Economic hardship is also a strong predictor of frequent residential mobility, and while food or cash assistance is associated with higher mobility, it moderates the hardship-mobility association. Supportive neighborhoods are associated with lower odds of moving. In turn, frequent moves more than double children’s risk of ACEs. Supportive and safe neighborhoods provide protective benefits, while detracting elements exacerbate adversity. We conclude that reducing frequent moves and strengthening neighborhood supports are critical strategies for mitigating childhood adversity.Published versio
Journal of Biomechanics
Full text linkBack-support exoskeletons (BSEs) offer the potential to reduce the risk of work-related musculoskeletal disorders of the lower spine. Although surface electromyography (sEMG) is commonly used to evaluate BSE effects on muscle activity, there are practical limitations to monitoring multiple trunk muscles while wearing a BSE. Musculoskeletal models offer an alternative, providing estimates of muscle activity that may complement or substitute direct measurements. We evaluated estimates of muscle activity using the gait-full-body model from the AnyBody™ Modeling System (AMS) and the OpenSim full-body thoracolumbar model. These evaluations were done for two bilateral lumbar extensors (longissimus and iliocostalis), vs. normalized sEMG (nEMG) data obtained from 18 participants who completed symmetric and asymmetric lifting tasks with and without two different BSEs. Comparisons were done using maximum normalized cross-correlation (MNCC), root-mean-square error (RMSE), and peak activity (95th percentile). Both AMS and OpenSim yielded strong associations with measured nEMG (mean MNCC: 0.90–0.95), though moderate errors were found (mean RMSE: 0.09–0.15). Model estimates captured general reductions in peak muscle activity with BSE use, consistent with nEMG, but with varying magnitudes. Muscle activity estimates had smaller MNCC and larger RMSE in BSE conditions, suggesting limitations in current simplified human–BSE interaction models. While both modeling tools show promise for estimating trunk muscle activity during occupational tasks, further refinement is needed—particularly to improve accuracy during complex movements and BSE-assisted scenarios. These findings support the potential utility of musculoskeletal models in ergonomic assessment and exoskeleton evaluation but underscore the need for cautious interpretation.Accepted versio
Perceptions of Leader Development Programming by College Students with Introverted Personalities
No full textThis is a qualitative study on the perceptions of leadership development programming by students who identified as more introverted than their peers. The study examined the self-efficacy of these students towards leadership and the contributing factors to the achievement of their efficacy to be a leader. Conducted at a Research I, land-grant institution, the study consisted of interviews with students who identify as more introverted than their peers. Interviews allowed the researcher to examine their experiences and attitudes towards their own leadership development. The purpose of the study was to better understand the concept of leadership efficacy in the context of introverted student experiences. Findings from the study highlighted the importance of close relationships as a source of vicarious learning, verbal encouragement, and as a steadying influence on emotional well-being for introverted students developing as leaders. Students value teaching as an optimal model for leadership. As they navigated the rigors of serving in leadership roles in college, students looked to close relationships and regular practices of self-care to mitigate the impacts of stress on their energy. This study contributes to the body of knowledge on the understanding of personality and leadership development, specifically how self-efficacy is manifested in those with an introverted personality.Doctor of PhilosophyThis study examined the perceptions of leadership development programming among college students who have more introverted personalities than peers. While there has been significant investment in higher education in leadership development programming, widespread dissatisfaction with leaders is present in the United States. An appropriate response to these general concerns on the state of leadership is to examine the perspective of emerging leaders who navigate their motivations to lead against a backdrop of historical biases and present-day assumptions. As some have perceived an "extraverted bias" in many of our societal institutions, it is important to consider whether such biases are ingrained in leader development programming that ultimately hinders the development of potential leaders. This study found that many students did recognize introversion as a hinderance to their development in some facets of leadership such as public speaking and engaging with larger groups. Students routinely practiced coping strategies to mitigate stress, and concurrently close relationships were a valued part of encouragement, vicarious learning, and emotional resilience as students navigated leadership roles. Students aspired to serve in roles as a teacher. At a time of significant leadership dissatisfaction, efforts should be made to fully account for the barriers that prevent new and diverse leaders from matriculating into leadership roles
Enhancing Screening for Perinatal Mood and Anxiety Disorders in Critical and Emergency Care: A Multidimensional Approach Leveraging Machine Learning and System Dynamics
No full textPerinatal Mood and Anxiety Disorders (PMAD) encompass a spectrum of conditions, including postpartum depression, anxiety, stress, perinatal psychosis, obsessive-compulsive disorder, and post-traumatic stress disorder. Among these, postpartum depression is one of the most common obstetric complications and a leading risk factor for maternal suicide. Caregivers of infants admitted to neonatal intensive care unit (NICU) are particularly vulnerable, with up to 45% screening positive for depressive symptoms. Early detection of PMAD is essential, as untreated symptoms can contribute to infant neurodevelopmental delays, recurrent emergency department (ED) visits, and long-term maternal–infant complications.
To address persistent gaps in screening and treatment, the PMAD team at Children's National Hospital was established to strengthen psychological support for caregivers in both NICU and pediatric emergency department (PED) settings. Despite these initiatives, screening rates remain suboptimal, highlighting the need for a system-level understanding of the barriers and opportunities within the current process.
This dissertation applies a multidimensional approach to enhance the PMAD screening system through three interconnected studies. The first develops and evaluates machine learning algorithms to identify caregivers at high risk for depression, enabling prioritized screening. The second employs a system dynamics group model–building approach to identify the drivers and barriers influencing PMAD screening in NICU and PED workflows. And finally, the third study develops a system dynamics simulation model to test potential interventions and assess how system-level adjustments can improve screening efficiency and caregiver support.
Collectively, these studies advance the understanding of PMAD screening as a complex system and provide actionable insights for improving early detection and intervention. The findings have the potential to guide the design of more efficient, data-driven screening systems and to position the PMAD program at Children's National Hospital as a model for promoting maternal and infant well-being in similar healthcare settings.Doctor of PhilosophyMany new parents face mental health challenges during and after childbirth. Conditions like postpartum depression and anxiety, known as Perinatal Mood and Anxiety Disorders (PMAD), affect many new parents and can be especially serious for families with babies in the neonatal intensive care unit (NICU). Nearly half of these parents show signs of depression, which can affect their well-being, their ability to bond with their infants, and even lead to higher use of emergency medical care.
Children's National Hospital has taken steps to better support parents through a specialized PMAD team, but many parents are still not being screened or connected with help. This dissertation focuses on finding better ways to identify and support parents at risk. First, it explores the use of artificial intelligence to flag parents who may need extra attention. Next, it brings together healthcare providers to map out the challenges and opportunities for improving screening.
Finally, it uses computer simulation to test new strategies to make the system work more effectively.
The goal of this research is to strengthen how hospitals identify and support parents struggling with mental health during and after childbirth. By improving screening systems, hospitals can provide earlier care, reduce stress on families, and ultimately improve the health of both parents and their babies
Safeguarding the National Broadband Map: Detecting Strategic Misreporting and Auditing Broadband Deployment via a Risk-Based Monitoring System
No full textThe National Broadband Map (NBM) serves as the source of truth for determining location eligibility for funding programs, most notably, the Broadband Equity, Access, and Deployment (BEAD) program that allocated an unprecedented 42.45 billion through the Broadband Equity, Access, and Deployment (BEAD) program, which aims to provide universal internet access across the country. However, because this map relies on data self-reported by Internet Service Providers (ISPs), it creates a conflict of interest where providers may be incentivized to manipulate the system to influence where funding is sent. In this work, we develop a scalable monitoring framework as the blueprint to a system that help stakeholders protect this public investment by detecting inaccurate or strategic provider filings. First, we establish the necessary technical foundation by linking the corporate names listed on the map to their identity on the public internet, which allows us to verify specific claims in the NBM using real-world measurements. By matching four independent registration identity data, we successfully identified 72% of the providers listed in the map, allowing us to attribute real-world measurements to them. Second, we provide evidence that providers are indeed gaming the system by identifying strategic reporting patterns. We developed a framework to detect illogical "flip-flops," where a provider claims to offer service just in time for funding deadlines and removing them in the future. By filtering these events based on their timing and impact on funding eligibility, we identified more than 122,000 highly suspicious claims across 25 states. These findings demonstrate that the current map is prone to errors and that existing safeguards are insufficient. Finally, we introduce a continuous monitoring framework that uses statistical modeling to compare a provider's claims against actual speed test data from users. By continuously monitoring for locations that claim to be upgraded but fail to show actual performance improvements, our framework provides a blueprint for a monitoring system that enable skateholders to efficiently prioritize their verification efforts toward the most suspicious cases. Ultimately, our work demonstrates that protecting the integrity of large-scale government programs requires systematic and continuous monitoring
Tourism Management
No full textThis study investigates the determinants and timing of hotel booking cancellations through an integrative theoretical and empirical approach. Drawing on the theory of planned behavior, transaction cost theory, prospect theory, and strategic decision-making, we offer a comprehensive framework that explains both why and when cancellations occur. Utilizing a unique dataset of over two million hotel bookings from Mallorca, Spain (2021–2024), we apply time-to-event modeling and a linear probability model to explore cancellation patterns. Our results show that cancellation behavior is determined by a complex interplay of refundability terms, booking window, consumer nationality, travel party composition, hotel characteristics, and pricing dynamics. Findings reveal a non-linear (inverted U-shaped) relationship between booking window and cancellation likelihood, and highlight strategic consumer behavior around penalty windows and rebooking opportunities. This study contributes to tourism literature by combining theoretical depth with large-scale observational data to explain temporal and behavioral nuances in booking cancellations.Published versio
Bioengineering
No full textThis study evaluated the feasibility, image quality, and referral accuracy of a patient-operated optical coherence tomography (OCT) device (SightSync) compared with technician-acquired Heidelberg OCT. This study was conducted in a Veterans Affairs retina clinic (Cleveland, Ohio), resulting in a predominantly male (98%) study population representative of the local veteran demographics. One hundred patients attempted self-administered OCT imaging after brief instruction, yielding 118 successful scans (59% of eyes) with no significant association between scan success and age, visual acuity, or diagnosis. Quantitative analysis of 142 paired images showed that SightSync produced interpretable scans with comparable sharpness to Heidelberg OCT, though signal- and intensity-based metrics (signal-to-noise ratio; SNR, contrast-to-noise ratio; CNR, entropy, pixel intensity; p90) were lower, consistent with hardware differences between a compact patient-operated prototype and a clinical-grade system. Among 121 high-quality SightSync scans, referral decisions demonstrated strong agreement with Heidelberg OCT, with a sensitivity of 83.9%, specificity of 75.6%, and a negative predictive value of 93.2%, indicating reliable exclusion of clinically significant pathology. These findings demonstrate that patients can independently acquire clinically interpretable OCT images and that SightSync provides safe, conservative triage performance—supporting its potential as a scalable community-based retinal imaging solution—while a review of unsuccessful scans has identified prototype modifications expected to further improve device feasibility.Published versio