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FUNCTIONAL ROLES OF AQUAPORIN 5 IN BREAST CANCER METASTATIC INITIATION MODELED IN VITRO
No full textDespite causing 90% of cancer-related deaths, metastasis remains untargeted by widely available therapeutics. This deficiency of viable treatments stems from the field’s lack of foundational knowledge underlying the mechanistic progression of metastasis. Scientists have extensively used standard in vitro and in vivo models to study the disease state. However, these models are widely recognized for their limited translatability to human cancers. Commonly used in vitro models drastically oversimplify the physical, biochemical, and cell-to-cell cues that would normally be experienced within the tumor microenvironment (TME); conversely, the in vivo models employed lack the ability for long-term real-time data acquisition necessary to delineate the mechanisms underlying cancer metastasis. Limitations of both model types have drastically mitigated a physiologically relevant understanding of metastatic initiation and, thus, the discovery of appropriate markers for facilitating this progression. Aquaporins (AQPs) are a family of transmembrane water channel proteins that could act as regulators of metastatic initiation. Some AQP isoforms are significantly overexpressed in cancer cells and the TME, contributing to enhanced cancer proliferation, rates of metastasis, adoption of aggressive states, and, most extensively studied, cell motility. Yet the field’s understanding of AQP-mediated metastasis is inherently insubstantial, derived entirely from these limited in vitro and in vivo models.
This dissertation elucidates the impact of the pro-metastatic isoform AQP5 on enhanced cell motility within complex in vitro microenvironments. To accomplish this, AQP5’s role in tumor progression was assessed from biological and biophysical perspectives. Additionally, in vitro models were developed and validated to better study AQP5’s involvement in metastatic initiation. This dissertation presents a newly identified mechanism by which AQP5 facilitates spheroid invasion, along with AQP5-based corruption of TME-resident cells and its role in promoting pro-metastatic cellular mechanical properties. Additionally, it characterizes a new model to study how biophysical cues dictate AQP5-mediated cell dynamics and introduces an in vitro system designed to recapitulate metastatic initiation
VACANT TO VIBRANT – Revitalizing Urban Spaces through Adaptive Reuse
No full textHow can adaptive reuse design strategies be applied to support urban renewal and better placemaking? Urban areas globally face continuous evolution driven by population, economic, and environmental shifts. This evolution often leads to development projects that prioritize demolition over preservation, resulting in the loss of cultural landmarks, increased waste, and urban sprawl. Adaptive reuse presents a sustainable alternative, challenging the misconception that it merely involves preserving structures in static forms. Instead, adaptive reuse reimagines existing buildings, transforming them into vibrant, multifunctional spaces that meet modern programmatic demands while preserving cultural and environmental assets.
This thesis explores how adaptive reuse strategies can serve as tools for urban renewal and placemaking, addressing challenges like demolition bias and the underutilization of existing structures. By integrating innovative architectural interventions as a kit of parts, adaptive reuse enables the creation of spaces that foster community engagement, stimulate local economies, and enhance sustainability. A proposed “kit of parts” framework offers adaptable design strategies, such as vertical additions, facade rejuvenation, and interior reconfigurations, that empower stakeholders to implement adaptive reuse dynamically and effectively.
By positioning adaptive reuse as a catalyst for urban regeneration, this research highlights its potential to drive economic growth, reduce environmental impact, and strengthen social and cultural cohesion, ultimately reframing it as a cornerstone of sustainable urban development
REVOLUTIONIZING RETAIL: THE IMPACT OF TECHNOLOGY STRATEGIES ON OPERATIONAL PERFORMANCE
No full textThis dissertation comprises three chapters, each focusing on a different technology used to facilitate operations and performance in the retail industry. In the first chapter, I examine virtual try-on (VTO) technology in the eyewear industry. VTO has gained traction among both pure online and dual-channel retailers. My results indicate that VTO significantly improves overall performance, particularly benefiting dual-channel retailers. This unexpected result is likely due to the facilitation of webrooming, where shoppers research products online but make purchases offline. VTO, thus, helps retailers to retain webrooming customers, mitigating the risk of lost sales to competitors. Furthermore, this study highlights the contributions of VTO to retailer resilience during unexpected disruptions. These findings underscore VTO’s role as a critical tool for maintaining business continuity.
The second chapter explores mobile consumer scanning technology (MCST) for grocery retailers. Using traffic and sales data, I examine the impact of MCST on in-store customer dwell time, average transaction size, and number of customer visits. The findings reveal that MCST leads to a reduction in in-store dwell time. Moreover, the technology results in increased customer visits. However, MCST also leads to a decrease in spend per shopping visit, as the technology allows customers to track spending as they shop. Extended analyses further reveal that MCST alters daily shopping patterns and increases retailer’s sales volume. These findings advance the literature on the application of consumer-centered retail technologies, highlighting both theoretical and managerial implications from the implementation of MCST.
The last chapter focuses on design technologies for furniture retailers. Fit risk significantly impedes furniture sales, since consumers may be reluctant to purchase furniture if they are unsure how it will fit into their homes. Retailers use pre-sales practices, like room planners, augmented reality (AR) technology, and online (human) interior designers to mitigate fit uncertainty. Post-sales practices, in particular, lenient return policies, further address fit concerns. Analyzing data from 102 U.S. furniture retailers over five years, I find that pre-sales and post-sales practices independently enhance sales performance but often act as substitutes. Moreover, extended analysis reveals complex interactions among the pre-sales and post-sales practices in producing online and offline sales
Sharp Interface Limits of Some Models of Cell Migration
No full textThis dissertation is concerned with the analysis of some variants of the classical Patlak-Keller-Segel systems of partial differential equations. These systems are common models for the population density of a group of organisms subject to the simultaneous antagonistic effects of aggregation and a mechanism that prevents overcrowding. The aggregation is the result of an attraction to a chemical signal (chemotaxis) that is produced by the organisms themselves. Overcrowding is modeled by a population pressure resulting in a degenerate, nonlinear diffusion, e.g., of porous medium-type.
Our aim is understanding the dynamics of these systems in regimes where the organism population is large and when either the timescale for organism migration is instantaneous relative to the relaxation of the chemical signal (elliptic-parabolic systems) or when the organism motion is only somewhat faster than the chemical relaxation (parabolic-parabolic systems). We show, in the limit of a large population, that centered energies for which these systems are gradient flows Γ-converge toward (multiples of) perimeter functionals. Then, we study the singular limit of the gradient flows themselves. For each system, when the initial state of the system is well-prepared, phase separation occurs in the limit of a large population, resulting in the formation of a sharp interface partitioning the environment into a region with no organisms and a region containing the organisms arranged at a uniform density. We then derive, conditional on the satisfaction of an energy convergence hypothesis, evolution equations for these sharp interfaces. For the elliptic-parabolic system, the sharp interface evolves by volume-preserving mean-curvature flow while parabolic-parabolic system's emergent interface evolves by a Hele-Shaw free boundary problem with surface tension and kinetic undercooling
Advice but no Consent: Ratification of Human Rights Treaties in the United States Senate
No full textHow has the United States, a country which advertises itself as the preeminent defender of human rights, managed to also boast among the fewest ratifications of human rights treaties? Within the Senate’s constitutional advice and consent responsibility, no other treaty subject matter suffers from a greater rate of non-ratification. No other type of treaty requires so much time to receive Senate consent. While the US possess a number of characteristics that make it unique relative to the rest of the world – perhaps even exceptional, I contend that an analysis of US engagement with human rights treaties must focus on the contents of the treaties themselves.
Studies of treatymaking such as rational design have long considered the strength of treaty obligations as a factor in whether states can come to an agreement. I build upon this knowledge by analyzing the human rights treaties considered by the Senate in terms of their procedural and substantive content. By doing so, I am able to account for what factors of treaty design are associated with Senate approval of human rights treaties as well as the amount of time required for it to do so. I further explore these dynamics by reviewing Senate deliberations regarding human rights treaty ratification over the past 75 years. I close with an analysis of how the Senate has chosen to limit those human rights treaties it has ratified through the usage of reservations, understandings, and declarations (RUDs).
By evaluating the human rights treaties which have been ratified versus those which have not, I find that an emphasis on positive rights and the rights of women in a human rights treaty results in a significantly reduced likelihood of ratification. I also find that an emphasis on rights related to race and ethnicity is consistently associated with delayed Senate approval for ratification. Conversely, the US ratification record shows no correlation between ratification and a treaty’s procedural makeup whether considering domestic procedures, such as implementation or enforcement requirements, or international mechanisms, such as oversight or dispute resolution mechanisms.
While Senate deliberations do spend a great deal of time on procedural components of treaties, senators who criticize these procedures tend to do so for those treaties which emphasize the substantive rights noted above. Further, although the Senate generally takes great care to not dispute rights contained within human rights treaties, senators do appear willing to refute the rights of women contained in treaties such as CEDAW. Although the Senate has shown willingness to use RUDs to address procedural aspects of treaties it finds concerning, it has not proven willing to use these tools to permit ratification of treaties emphasizing positive rights and the rights of women. These results offer support for the contention that US ratification of human rights treaties is contingent on the contents of human rights themselves
AUGMENTING THE ARCHIVIST: TAKING LIBRARIES AND ARCHIVES INTO THE FUTURE WITH ARTIFICIAL INTELLIGENCE AND MACHINE LEARNING
No full textThe digital tsunami is upon us - digitization projects are no longer small-scale boutique workings and the rapid approach of primarily born-digital archiving necessitates a fundamental shift in the research questions, tools, and processes of LAM professionals (Libraries, Archives, and Museums). Machine Learning (ML)/Artificial Intelligence (AI) will be a key component of the answer. The urgency of investigating this space is reflected in a number of recently launched research initiatives, both in academia, such as the InterPARES Trust AI (an international research project aiming to design, develop, and leverage AI to support the ongoing availability and accessibility of trustworthy public records: 2021-26), and with emerging research monographs such as Archives, Access and Artificial Intelligence (Lise Jaillant (Ed.), Bielefeld University Press, May 27, 2022), and also in cultural institutions themselves, such as at the National Archives and Records Administration (NARA) (where research into self-describing records has been suggested in order to explore how to automatically produce descriptive metadata for public access with minimal archivist intervention, and where for the first time, cultural archival big datasets have been shared with the public in order to enable AI/ML explorations).
This dissertation is an important contribution to these pressing emerging challenges and the need to develop a new research agenda based on cutting-edge crossover work at the intersection of archival and data science. We develop real-world case studies whose contexts typify this field on a precipice and will allow us to advance solutions in this new research space. The dissertation is organized around three published papers. The first study, comprises a review of literature in the Computational Archival Science research space as well as offering important research contributions in terms of characterizing fundamental changes observed in the field as archives only begin to take deposits from the digital workforce. The analysis uses data science and Large Language Model (LLM) methods. The second study, based on a library collection from OCLC, explores the case of a massive consolidated catalog with challenges related to the cleaning of multilingual MARC records at the million-records scale. We develop and prototype two approaches – an innovative ML model that predicts the likelihood of errors in new ingests, and an algorithm that produces relevant statistical language probabilities to identify and repair transliteration errors. The effectiveness of these two methodologies is evaluated against established metrics. The third study, based on an archive collection from Spelman College, explores the case of a small university archive with a highly engaged alumni community pushing for greater access to and details about the archives’ photograph collections. We investigate the potential development of automated workflows to convert Dublin Core metadata to Archival Linked Data. We further assess the potential effectiveness of these types of automation pipelines and suggest new approaches for metadata extraction and linking of cultural resources.These papers, each grounded in their specific contexts, in aggregation suggest a new research agenda that addresses the need for libraries and archives to adapt to the massive shifts in scale, speed, accuracy, diversity, connectivity, rapid engagement and co-creation that are demanded by the challenges of the Digital age
WATCHING PAINT DRY: TOXICITY AND XRF DETECTION OF COPPER IN SEDIMENT CONTAMINATED BY DRYDOCK MAINTENANCE
No full textAntifouling hull coatings prolong the service lives of vessels and increase fuel efficiency by protecting against biofouling organisms. One of the most effective types of antifouling coating is biocide-infused epoxy. Organotin coatings, a popular and effective class of biocidal coating, were largely banned in the 2000s in recognition of their severe environmental impact and replaced with paints using copper or zinc as their primary biocides. Coating maintenance in shipyards can still release material such as paint fragments into the environment, which could contribute to the presence of microplastic (MP) paint particles in sediment near shipyards. These paint particles, like other microplastics, are often classed by size and polymer type, but in all plastic wastes manufacturing additives are often more environmentally consequential than the polymers that make up the bulk of the material. This study investigated whether it was possible to use portable X-Ray Fluorescence Spectrometry (XRF) to assess the presence of copper-based biocidal Antifouling Paint Particles (APP) in the sediments near active shipyards and whether toxicity of these sediments was correlated with copper content when compared to sediment spiked with copper products in the lab. Toxicity was evaluated using 10-day acute toxicity test procedures for the amphipod Leptocheirus plumulosus modified for reduced volume.
We hypothesized that sediment toxicity would be predicted by XRF-reported copper content. We tested spiked sediment series of increasingly complex and environmentally representative matrices for toxicity, beginning with pure copper compounds, proceeding to new and used antifouling paints and then used abrasive blast media contaminated with these coatings collected from active shipyards. Finally, we performed toxicity tests and XRF analysis of field-collected sediments from three urban rivers (Cuyahoga River, OH, USA; Curtis Creek, MD, USA; and Elizabeth River, VA, USA). Geographic differences in copper concentrations relative to location of the nearest shipyard(s) and number of yards were considered.
Ultimately, this research will lay the groundwork for further classification of understudied MPs in the marine environment and provide a starting point for further assessment of sediments near shipyards
Madwomen in the Killing Jar: Madness, Adaptation, and Performance in Kate Soper's Voices from the Killing Jar
No full textU.S.-American composer, writer, and performer Kate Soper describes a killing jar as “a tool used by entomologists to kill butterflies and other insects without damaging their bodies: a hermetically sealable glass container, lined with poison, in which the specimen will quickly suffocate.” This premise provides the central motif for her 2012 monodrama for soprano and chamber ensemble, Voices from the Killing Jar. In the piece, she adapts narrative elements from the stories of eight heroines—originating from a wide range of literary and historical sources—who she believes are trapped in their own metaphorical killing jars. This thesis examines Soper’s adaptation of these eight heroines’ texts through the lens of madness and madwomen. I analyze the musical and textual contents of three movements: “My Last Duchess: Isabel Archer,” “Mad Scene: Emma Bovary,” and “Her Voice is Full of Money: Daisy Buchanan.” Drawing on scholarship on performance-based madness and historical psychiatric practices in the United States, England, and France, I analyze Voices in the context of madness in music, history, and literature. Finally, I address the entire monodrama, engaging with the theme of spectatorship to demonstrate how the piece generates empathy for its “mad” heroines. By interpreting Voices from the Killing Jar in the context of madness, adaptation, and performance, this thesis contributes to a growing body of scholarship on transmedia adaptation and expands the study of madness in musical performance beyond the nineteenth century
DETECTION AND CHARACTERIZATION OF LAVA TUBES FROM SURFACE SIGNATURES: TWO NEW APPROACHES
No full textLava tubes are sinuous volcanic caves formed when a lava flow develops a solidified crust before draining out. On other planets and moons, lava tubes could be ideal sites for future exploration or habitation, providing practical and scientific benefits. Lava tubes are difficult to study without in-situ exploration, which is impossible for extraterrestrial, inaccessible, or filled tubes. We present two new techniques to constrain the internal morphologies of lava tubes, relying only on remotely observable surface features. Through modeling, we predict the surface features that lava tubes produce and quantify how the dimensions of these surface features depend on the dimensions of the tubes. Looking for these features in real data reveals several candidate tubes and allows us to constrain their dimensions. Large tubes on the Moon should cause tensile cracks in predictable patterns that reflect tube dimensions. Such cracks near discontinuities in Rimae Mairan, Sharp, and Marius indicate lava tubes with widths less than 2 km. Cracking inside lunar tubes would impair the usability of the floor for exploration, leaving less than 400 m of contiguous pristine floor in these three cases. Inflation ridges above tubes can also reveal tube morphologies. By modeling how Valentine Cave inflated, we constrain what conditions and age it must have had to produce the observed ridge. It and two similar examples must have inflated within the first 400 hours after roof formation. We build from this idea and discover a new, widely applicable relationship between the dimensions of an inflation ridge and the height, roof thickness, and width of its tube. From ridge topography alone, this relationship constrains a range of possible tube shapes. Searching for inflation ridges in a LiDAR dataset of the Lava Beds National Monument reveals eighteen candidate tubes. Most of these tubes share a similar range of possible shapes; one ridge shows a consistently different shape range, possibly indicating different formation conditions. Combined with constraints from other sources on two of these tubes, the shape ranges narrow to more specific results. These methods constitute two novel tools to find and study lava tubes on Earth and beyond
Microbial and Chemical Water Quality Assessments Across the Rural and Urban Areas of Nepal: A Scoping Review
No full textNepal is currently facing critical water quality challenges due to urbanization, water management and governance issues, as well as natural disasters. This has resulted in the presence of harmful contaminants (e.g., pathogens, nitrates, arsenic) across multiple water sources, subsequently leading to waterborne disease risks (e.g., cholera and typhoid). In response to these environmental and public health concerns, we conducted a scoping review to assess microbial and chemical contaminants in drinking and irrigation water in Nepal, as well as their potential impacts on public health. Following the JBI Manual for Evidence Synthesis and the PRISMA-SCR guidelines, we systematically searched for pee-rreviewed literature on Nepal’s water quality in seven databases. Of 3666 unique records screened using predefined inclusion criteria, 140 met our criteria. The studies encompassed a variety of methodological designs, with the majority focusing on water sources in the Bagmati province. Bacteria and arsenic emerged as the most prevalent contaminants. Additionally, diseases such as arsenicosis and typhoid remain widespread and may be linked to contaminated water sources. The review identified key gaps in Nepal’s water quality management, including limited geographic research coverage, inconsistent testing protocols, weak regulatory enforcement, and a lack of integration of water quality with public health planning. Our findings underscore the urgent need for effective surveillance systems and a robust regulatory framework to promptly respond to water contamination events in Nepal.S.C., A.C., Y.A., A.R.S., and L.M. were supported by an Institutional Grant from the University of Maryland Grand Challenges Program that established the Global FEWture Alliance. S.C. and A.R.S. were supported by NRT-INFEWS: UMD Global STEWARDS (STEM Training at the Nexus of Energy, WAter Reuse and FooD Systems), which was awarded to the UMD School of Public Health by the National Science Foundation’s National Research Traineeship Program (Grant #1828910).https://doi.org/10.3390/ijerph2210152