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ENHANCEMENT OF BIOLOGICAL PHOSPHOROUS REMOVAL FROM WASTEWATER
No full textMinimizing the anthropogenic nutrient input such as phosphorous (P) to aquatic ecosystems is necessary to prevent eutrophication. Conventional chemical precipitation of P in wastewater using alum is an efficient approach but a large amount of biosolids is produced and the use of chemicals is costly. Enhanced biological phosphorous removal (EBPR), driven by polyphosphate accumulating organisms (PAOs), offers a promising alternative. However, PAOs require an external carbon (C) source for optimal P removal, and competition from other microorganisms, along with low influent carbon availability, can limit EBPR efficiency. This dissertation investigates strategies to improve biological P removal by evaluating the role of PAOs in activated sludge and exploring efficient C sources.First, the contribution of microorganisms to remove P evaluated and different C sources that have been used in EBPR discussed. Among various organic compounds, acetate and propionate emerge as the most favorable options for achieving stable and efficient P removal by PAOs. However, if these organic compounds are manufactured using fossil fuel-derived materials, their addition will reduce the economic and environmental benefits of EBPR. In comparison, in-line fermentation and side-stream EBPR (S2EBPR) are more advantageous in generating C sources for PAOs. Then, to connect the previous studies to real-world applications, a full-scale wastewater treatment has been studied. Batch tests were performed to assess the facility's performance under different conditions, incorporating data from both the facility and activity tests. Batch experiments revealed a strong positive correlation (r = 0.91) between temperature and C consumption rate (3.56-8.18 mg-COD/g-VSS/h) in the system, with temperature ranging from 14 to 18 °C. The anaerobic P-release to COD-uptake ratio decreased from 0.93 to 0.25 mg-P/mg-COD as the temperature increased, suggesting competition between PAOs and other C-consumers, such as heterotrophic microorganisms, to uptake bioavailable C. Lastly, to evaluate the potential of crude glycerol (CG) as a waste-derived C source in enhancement of PAOs activity batch experiments were conducted and kinetic parameters were measured to evaluate the direct and indirect application of CG. Promising results were observed to use CG for supporting PAO activity. The results indicated that CG addition to waste activated sludge (WAS) fermentation increased soluble COD (sCOD) of the fermenter effluent by 64.6 ± 5.7% after 5 days compared to WAS alone. WAS and CG co-fermented sludge improved PAO activity, increasing P release and uptake rates by 61.0 ± 11.8 and 22.2 ± 3.3%, respectively, compared to WAS-alone fermented sludge
Bayesian Hierarchical Meta-Analysis Using Individual Participant Data for Modeling Heterogeneous Dropout Patterns Across Multiple Clinical Trials
No full textMissing data is a pervasive issue, notably in clinical trials and prospective studies employing a longitudinal design. This problem becomes particularly pronounced when dealing with data from multi-study clinical trials. Many established research teams undertake multiple clinical trials in closely related domains, each of which may exhibit distinct patterns of patient attrition/dropout. However, due to the shared group panel and study administration, these dropout patterns are often believed to exhibit similarities across these trials. While models addressing single dropout mechanism have been extensively investigated, the analysis of heterogeneous dropout patterns remains understudied. To leverage heterogeneous data and integrate information from multiple missing mechanisms, the first part of this dissertation discusses a new meta-analysis strategy based on individual participant data (IPD) to model observational-level dropout patterns over multiple trials and improve statistical inference via a Bayesian Hierarchical Model (BHM). Extensive simulation studies were conducted to demonstrate the superiority of the new method over existing methods in terms of reduced bias, smaller estimation variability, and higher statistical power. The proposed method was also applied to 13 clinical trials for schizophrenia research exploring demographic and clinical determinants of dropout.
Most clinical trials enroll adults and treatment efficacy data in children and adolescents have become scarce. The second part of this dissertation deals with network meta-analysis in examining efficacy of schizophrenia treatments in underage population. Traditional meta-analysis is restricted to direct comparison of treatments in parallel study designs. However, network meta-analysis is a special kind of meta-analysis for the comparison of multiple treatments simultaneously in a single analysis by combining direct and indirect evidence. The direct evidence is obtained from randomized control trials with direct comparison of treatments in parallel study design. The indirect evidence is obtained from comparisons of one or more common comparators by transitivity. The direct and indirect pooled evidence is the network estimate. Network meta-analysis is vital in examining the effectiveness of different treatments in randomized control trials. Accordingly, it is gaining popularity
PALS 2025 : Deliverable 2
No full textThis presentation covers the Precedents, Site Analysis, Business Engagement, and Student Reflections of the UMD PALS 2025 Project: Green Isles.Acknowledgements: School of Architecture and Urban Planning, Creative Placemaking Minor, PALS (Partnership for Action Learning in Sustainability), Purple Line Corridor Coalition, Takoma Langley Crossroads Development Authorityhttps://drive.google.com/file/d/18iXTJ6DAxtBvqiWiZNlV42Nr8htyk-b2/view?usp=drive_lin
ENGINEERING WHILE BLACK: CENTERING LIVED REALITIES TO DISRUPT DESIGN AND BUILD BLACK FUTURES
No full textThis dissertation, Engineering While Black: Centering Lived Realities to Disrupt Design and Build Black Futures examines the manifestations of anti-Blackness within engineering spaces and explores how the lived experiences of Black professionals in the fields of Science, Technology, Engineering, and Math (STEM) can serve as a radical foundation for inclusive, culturally responsive design. Utilizing a phenomenological-narrative hybrid methodology, this study amplifies the voices of Black engineers, designers, scientists, and technologists to understand how identity, culture, and systemic barriers intersect in their professional journeys. Findings are organized into three core themes: (1) Identity Formation and Black Cultural. Representation, which explores the complex definitions of Blackness and the erasure of cultural expression in STEM; (2) Pathways into STEM and Systemic Barriers, which highlights institutional exclusion, bias in design practices, and the burden of representation; and (3) Addressing Community Issues, Mentorship, and Legacy, which illustrates how Black professionals design with their communities in mind, positioning their work as both resistance and restoration. A key contribution of this dissertation is the development of the Black-Centered Design Process. This framework intentionally prioritizes Black cultural knowledge and lived experiences in engineering design to challenge Eurocentric norms and foster equity-based innovation.Additionally, this work broadens the theoretical applications of Afrofuturism, Critical Race Theory, and Designing Black Futures by anchoring them in practical, real-world design interventions. By framing Black identity not as a variable to control but as a critical lens through which we can reimagine STEM, this dissertation offers transformative insights for engineering educators, human-centered designers, and policymakers. It demands inclusion and disruption—and charts a bold course for building Black futures through liberatory design
Program Synthesis for Quantum Applications
No full textQuantum computing has the potential to revolutionize various fields by solving problems intractable for classical computers. However, developing efficient quantum programs remains challenging due to the unique constraints of quantum systems, including noise, limited qubit connectivity, and hardware variability. Unlike classical programming, where high-level abstractions and optimized compilers ease development, quantum programming still relies heavily on low-level circuit representations, making manual implementation complex and error-prone. Program syn-thesis, an approach that automatically generates programs satisfying given specifications, offersa promising solution by optimizing quantum circuits while minimizing human effort. However,applying classical program synthesis techniques to quantum computing presents unique chal-lenges across different abstraction levels. The development of novel synthesis and verificationapplications specifically tailored for quantum programming is highly desired.In this thesis, we introduce three novel quantum program synthesis frameworks addressingkey challenges across different levels of quantum computing. First, we present QSynth, the firstframework for synthesizing unitary quantum programs with recursive structures, enabling efficientautomated verification. Second, we introduce MQCC, a quantum meta-programming frameworkthat balances trade-offs among multiple constraints specific to targeted applications and hardware.Finally, we propose NuQes, a neuro-symbolic quantum error correction (QEC) code synthesisframework that leverages heuristic functions generated by large language models (LLMs) tooptimize QEC code design. Together, these frameworks advance quantum program synthesis byimproving efficiency, reducing errors, and enhancing scalability
The R-Ras/FLNA Complex is Robustly Expressed in Glioblastoma Cells
No full textR-Ras, a small GTPase and member of the Ras superfamily, is involved in cellular signal transduction, migration, proliferation, and differentiation. R-Ras and FLNA (a cytoskeletal protein) form the R-Ras/FLNA complex, which is critical for maintaining the integrity of the endothelial barrier and promoting endothelial homeostasis. Cells that lack FLNA expression have impaired locomotion function, making them unable to migrate. The R-Ras/FLNA complex plays a prominent role in the blood-brain barrier (BBB). Glioblastoma (GBM), the most lethal primary brain tumor in adults, has a compromised BBB. We hypothesize that R-Ras activity affects GBM metabolic activity and migration. Ras activity in a cell line can be determined by performing an Active Ras Pull-Down Assay and running Western blots (WB) to probe them with an anti-Ras primary antibody. Ras activity monitors all Ras small GTPase activation, not just R-Ras. To emulate the fluid shear stress found in the BBB, we utilized cell spinpods at different shear stress levels. The results of this study will help us better understand how R-Ras and FLNA are involved in regulating the blood-brain barrier in infiltrative gliomas in future experiments
Sailing Into the Unknown: Applying the National Historic Preservation Act to the SS United States' Final Voyage
No full textThe National Historic Preservation Act was passed in 1966. It has since been amended several times and additional guidance has been published to assist federal agencies and the public in the preservation of America’s historic resources. Despite the continued expansion of the Act to include additional resource types and resource circumstance, there remain instances of first impression that do not fit into the official guidance. This paper seeks to apply the existing preservation legislation, regulations, and guidance to the SS United States. The ship has been listed in the National Register since 1999, and she was listed while docked in Philadelphia, Pennsylvania. In February 2025, the United States departed Philadelphia for Mobile, Alabama to begin the process of being converted into an artificial reef. The plan is to sink the ship in Gulf waters off the coast of Florida. The move raises several questions regarding her status in the National Register. First, does the relocation of the ship from Philadelphia mean the ship should be delisted? Second, if the ship remains in the National Register, which state historic preservation office has jurisdiction? Will it be Pennsylvania because that is the office on the National Register nomination form, or will it be Florida because that is the jurisdiction in which she will reside? Third, the SS United States was listed as a floating historic vessel, but she will no longer be floating when she is a reef, does this change in her classification or impact her place in the National Register
Primo Instructional Videos
No full textOver the summer of 2024 UMD libraries transitioned to Primo. This meant the library catalog looked totally different, had new features, and old features looked different visually. The TLS department, in order to support this transition, made instructional videos on how to use and navigate the new Primo catalog. These videos required collaboration between multiple departments in order for the videos to fully come to fruition. Instructional videos are important, but both the work needed to create them is often underestimated. Additionally, how to make them the most accessible and useful is not given enough attention.
With my poster, I hope to explain why instructional videos are important, using the Primo videos as an example. First, I want to discuss instructional videos, or how to videos, broadly. Then, I want to briefly explain how the Primo catalog is different, and what features and new parts of the catalog we needed to explain in our videos. Thirdly, I will spend the most time and space discussing the process we went through at TLS to make the videos. I will include a discussion of what we did, what I personally did, and what other departments did. I will discuss both the tools we used and our rationale as to why we did what we did
Firefighting Exoskeleton to Reduce Stress and Strain
No full textGemstone Team EXOOverexertion stress and strains and musculoskeletal disorders are the leading causes of
injury in firefighters. Lower back injuries resulting from lifting are prevalent in both fire and
Emergency Medical Service (EMS) calls. Exoskeletons which provide specialized support during
repetitive movements have been increasingly implemented in construction, manufacturing, and
healthcare settings in recent years. However, the unique temperature, weight, fit, and quick
donning requirements of an exoskeleton suited for use in firefighting renders current commercial
exoskeletons unsuitable for firehouse implementation. Team Exo aimed to close this gap in
research by exploring the requirements and testing methods of a firefighting exoskeleton. Several
iterations of the exoskeleton were completed and categorized into three distinct prototypes. The
exoskeleton consisted of dual-spring housings, leg attachments, and an upper body harness. The
spring system worked with a cable and plunger to compress the spring while squatting, and
decompress when rising; resulting in a loading of the spring on descent, and an assistive lifting
force on ascent. Several testing phases were completed, including competing at the American
Society for Testing and Material (ASTM)’s 2025 Exo Games and further testing at the National
Institute of Technology (NIST). The final prototype of the exoskeleton functioned as a facilitator
for the gluteus and hamstring muscles that assisted the user in lifting. Testing focused on
user-reported comfort and perceived assistance through a wide variety of firefighter specific
movements and followed the current industry-wide standards of exoskeleton testing. Further
testing with electromyography (EMG)s, models, and cardiopulmonary exercise testing (CPET)
would be beneficial, and should be expanded on when more comprehensive testing standards are established. Further modifications for compatibility with firefighting gear and material
improvements would also be necessary for firehouse implementation
DNA Aptamer Against Alzheimer’s β-Amyloid 42 Protein
No full textAlzheimer's disease is a chronic neurodegenerative disorder. Currently, there are 6.9 million cases in individuals aged 65+ in the US, with an expected rise to 13.8 million by 2060. Current diagnostic methods, such as spinal taps and brain scans, are invasive and not widely accessible, exacerbating public health inequities. Recently, antibody-based blood tests have been developed to detect Alzheimer's, but aptamer-based diagnostics can be a cheaper and more accessible alternative to these antibody-based diagnostics. This study aims to develop a DNA aptamer capable of binding to the β-amyloid 42 protein, a biomarker associated with Alzheimer's, for a wide range of potential diagnostic applications. We conducted positive and negative selections using a Ni-NTA bead-based in vitro selection method against a His-GST tagged β-amyloid 42 protein. During selection, we utilized asymmetric PCR and gel extraction to amplify the single-stranded DNA. Results indicated enrichment of target-binding sequences in early selection rounds, though we encountered issues with low yields from gel extraction. Future work includes optimizing gel extraction protocols, gel shift assays to measure binding affinity, and increasing selection stringency to enhance aptamer specificity and binding affinity. This research aims to further contribute to developing non-invasive, cost-effective diagnostic tools for early Alzheimer's detection, aligning with the broader goals of improving access to diagnostic resources for all