DRUM - Digital Repository at the University of Maryland

DRUM collects, preserves, and provides public access to the scholarly output of the university. Faculty and researchers can upload research products for rapid dissemination, global visibility and impact, and long-term preservation.

Submit to DRUM

Submit to DRUM

To submit an item to DRUM, login using your UMD credentials. Then select the "Submit Item to DRUM" link in the navigation bar. View DRUM policies and submission guidelines.
Equitable Access Policy

Equitable Access Policy

The University of Maryland Equitable Access Policy provides equitable, open access to the University's research and scholarship. Faculty can learn more about what is covered by the policy and how to deposit on the policy website.
Theses and Dissertations

Theses and Dissertations

DRUM includes all UMD theses and dissertations from 2003 forward.

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Recent Submissions

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    Dataset for First-Principles Thermodynamic Analysis of Ternary Chalcogenide Phase Change Materials
    (2026-07-28) Adams, Felix; Mo, Yifei
    Chalcogenide phase-change materials (PCMs) are important for nonvolatile memory and reconfigurable photonic technologies. The GeTe – Sb2Te3 mixture system, commonly referred to as GST, is the most well-known PCM family, but new PCMs are needed to broaden the accessible property space while retaining fast switching. We proposed a thermodynamic framework, motivated by Ostwald’s rule, for understanding and identifying PCM materials, since direct modeling of phase-transition dynamics is computationally expensive. Using first-principles calculations, we systematically evaluate the energetics of other ternary chalcogenide mixtures along binary-binary tie lines and their polymorphs. By comparing ground-state and metastable structures, we assess phase stability, miscibility, and the likelihood of GST-like polymorph-mediated crystallization pathways across a broad composition space. This dataset comprises the density functional theory calculation results for ternary chalcogenide structures generated by doping known binary chalcogenide compounds.
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    Quality Control of the CMS High Granularity Endcap Calorimeters
    (2026) Keffer, Braeden; Andrews, Peter; Cole, Cassidy; Wohl, Adeev; Kispert, Noah; Sundrum, Lakshmi; Belloni, Alberto; Alton, Zachary; Papageorgakis, Christos
    The Compact Muon Solenoid (CMS) at CERN will be receiving upgrades to its data collection instrumentation in preparation for a larger number of collisions and proportional higher radiation upon resumed functionality in 2030. The endcap calorimeters, which are the sections of the calorimeters most affected by radiation, will be replaced with new high granularity calorimeters (HGCAL), which are composed of radiation-tolerant silicon modules and plastic scintillators installed on top of printed circuit boards (PCBs). The focus of this project is to test and calibrate the electronic components installed on the PCBs; the assembled PCBs are referred to as “tileboards”. The process of testing boards is split into two phases: a reception test and a functionality test. The reception test consists of a visual analysis to search for defects, which, if found, are photographed and reported to the manufacturer. The functionality test consists of a light detection phase and a calibration phase. The tileboards’ response to light was tested by flashing LEDs situated next to the photodetectors on the boards. The tileboards were injected with electric pulses to simulate photon detection to calibrate the turn-on points of the photosensors’ response. The full suite of tests is conducted at room temperature, while a truncated version is conducted at a temperature of -30 ℃ to simulate the operating temperature of the HGCAL detector. The testing process is still ongoing, and it is estimated to complete by the end of the first quarter of 2027.
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    A Multiplex RT-LAMP-Lateral Flow Platform For Comprehensive Dengue Serotype Detection
    (2026-07) Darcheva, Alina; Dejene, Nuhamin; Hackel, Davis; Kim, Christine; Potter, Maya; Hilton, Shannon; Spirito, Catherine
    Dengue virus (DENV) is a mosquito-borne RNA virus responsible for approximately 400 million infections annually and exists as four distinct serotypes (DENV-1-4). Secondary infection with a different serotype significantly increases the risk of severe dengue, making rapid serotype differentiation critical. Current gold-standard methods, such as reverse transcription polymerase chain reaction (RT-PCR), require expensive equipment and centralized laboratories, limiting accessibility in resource-limited settings. This project aims to develop a low-cost, portable diagnostic platform that combines reverse transcription loop-mediated isothermal amplification (RT-LAMP) with a multiplex lateral flow assay (LFA) for rapid detection and differentiation of all four dengue serotypes. Serotype-specific primers are being designed and optimized for RT-LAMP. A portable heating device utilizing a fatty acid phase change material (PCM) and an Mg-Fe alloy reaction was successfully constructed to provide instrument-free amplification. The LFA mechanism was also validated by successfully immobilizing the control capture probe, demonstrating effective salt-mediated immobilization, a clear colorimetric response, and successful biotin-mediated gold nanoparticle capture. Initial testing with synthetic DENV-2 DNA demonstrated successful RT-LAMP amplification. These findings establish the feasibility of an inexpensive, field-deployable RT-LAMP-LFA platform with potential to improve early dengue diagnosis and outbreak surveillance in resource-limited settings.
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    Utilizing RNase J1 to Degrade Ribozyme Reporter Signal in Cell-Free Systems
    (2026) Saafan, Umme Hani; Kongne, Jodelle Nembot; Herbert, Alexandra; Dugan, Pierre; Spirito, Catherine
    Ribozymes are noncoding RNAs that are able to catalyze reactions, such as self-cleavage, and can be used to control the expression of downstream genes under specific conditions. In E.coli-based cell-free protein expression systems, native RNases cannot efficiently degrade transcripts generated following ribozyme self-cleavage. Exogenous ribonuclease RNase J1, from Bacillus subtilis, can selectively degrade RNA transcripts containing a 5’ hydroxyl group, and could potentially be used to turn off the expression of downstream fluorescent reporters. In this study, we designed cell-free reactions (CFRs) containing a Pistol self-cleaving ribozyme upstream of the fluorescent reporter deGFP. Pistol ribozyme reporter constructs were PCR amplified, cleaned, and quantified. RNase J1 was expressed in E.coli-based cell-free lysates and its expression was evaluated by an SDS-PAGE gel and Western blot. One-pot and two-pot CFR setups were used to evaluate the effect of RNase J1 on reporter fluorescence. Although RNase J1 expression was successfully detected, fluorescence measurements demonstrated high variability across experiments. Pistol reporter constructs produced fluorescence levels close to the negative control, making decreases attributable to RNase J1 difficult to distinguish, and RNase J1 did not consistently reduce reporter fluorescence under the conditions tested. Future work should optimize reporter fluorescence to improve signal above the background, repeat experiments to evaluate reproducibility, and investigate the effects of native RNases present in the cell-free lysate. If successful, this system could be adapted to ligand-responsive ribozyme reporters, allowing for the development of ribozyme-based biosensors for a variety of target molecules.
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    Getting Ahead of Small Business Displacement: Strategies for the Early Stages of Gentrification
    (Small Business Anti-Displacement Network, 2026-02) McManus, Sophie; Lung, Willow; June-Friesen, Katy
    This report examines how commercial gentrification unfolds in its earliest phases and identifies practical strategies to prevent displacement. Drawing on focus groups, conference sessions, and webinars with members of the Small Business Anti-Displacement Network (SBAN), as well as a review of existing research, this report finds that the earliest signs of gentrification appear long before the characteristics typically associated with gentrification, such as rising rents, an influx of higher-income residents, and physical redevelopment. Instead, early signals of gentrification are identifiable in long-term patterns of disinvestment, redevelopment planning decisions, and regulatory changes that quietly reshape neighborhoods.