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Evaluating the robustness of signal unmixing methods for multivariate optical spectroscopic process monitoring data
No full textNeal, Sharon L.The growing application of multivariate spectroscopic methods in process monitoring has created a critical need for robust signal unmixing techniques to resolve complex, overlapping datasets. This dissertation investigates the applicability and limitations of several signal unmixing frameworks for multicomponent optical spectroscopic process monitoring. The first project examines the comparative performance of Multivariate Curve Resolution–Alternating Least Squares (MCR-ALS) and Nonnegative Matrix Factorization using Multiplicative Update (NMF-MU) on simulated excitation–emission matrices (EEMs) under varying conditions of overlap and noise levels. The second project evaluates the limits of tensorization in combination with PARAFAC decomposition for resolving components from simulated emission decay matrices (EDMs), identifying noise thresholds and structural constraints beyond which the tensor model fails to deliver interpretable results. The third project applies constrained matrix factorization methods, including semi-NMF and convex-NMF, to Fourier-transformed EDMs collected during the photodegradation of Rose Bengal, a system known to involve excited-state reactions and overlapping emissive species. Each approach is benchmarked using simulated or experimental datasets, allowing for systematic evaluation of unmixing performance in realistic conditions. Collectively, the findings provide practical guidelines on the selection and application of signal unmixing methods for PAT, with a focus on model interpretability, resolution performance, and robustness under challenging conditions. Across all three projects, findings highlight both algorithmic strengths and contextual limitations, offering practical guidance for selecting appropriate signal unmixing techniques in multivariate spectroscopic monitoring.University of Delaware, Department of Chemistry and BiochemistryPh.D
Lens Development: Bringing signaling complexity into focus
No full textThis article was originally published in eLife. The version of record is available at: https://doi.org/10.7554/eLife.106519.
© 2025, Coomson and Lachke.
This article is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use and redistribution provided that the original author and source are credited.Ask yourself, what is necessary for you to read this article? And how are you able to discern between individual words or letters? Evolution has solved these challenges by developing a complex organ, the eye, that is similar in many ways to a camera. It has a lens that focuses light onto a light-sensitive tissue, the retina, which captures this information and relays it to the brain. For the lens to be effective, it needs to be transparent, and complex genetic pathways have emerged to ensure that this happens during development. In vertebrates, the majority of the cells in the lens are fiber cells.
Although the need for cross-talk between the lens and the retina during lens development was first noticed in 1901 (Spemann, 1901), the details of the impact of this cross-talk on the differentiation of lens cells did not become clear until the early 1960s. Reversing the orientation of a chick embryonic lens so that its anterior region faced the retina (rather than looking outwards) led to a dramatic cellular reorganization: the lens epithelium facing the retina differentiated into fiber cells, suggesting that a key signal from the retina drives this differentiation of lens cells (Coulombre and Coulombre, 1963). This signal was later revealed to be a protein called fibroblast growth factor (or FGF for short; Chamberlain and McAvoy, 1987), which, depending on its dosage, can induce epithelial cell proliferation or their differentiation into fiber cells in the lens (McAvoy and Chamberlain, 1989)
ASSESSING THE IMPACT OF PNEUMATIC AIR FRACTURING AND AIR SPADING WITH BIOCHAR ON URBAN SOILS FOR ENHANCED STORMWATER TREATMENT
No full textenterUrban soils are often greatly impacted by soil compaction, leading to
detrimental soil conditions. Two methods of de-compacting the soil, pneumatic air
fracturing and air spading were used to treat compacted soils at an urban park in
Washington D.C. The effects of these two techniques were evaluated over a six-month
period. The soil infiltration rate, saturated hydraulic conductivity, and penetration
resistance were measured over the course of three separate field visits as an indication
of the compaction of the soil. It was found that pneumatic air fracturing had a
measurable effect on penetration resistance, and therefore soil compaction, at certain
areas within the site. However, air spading had no measurable effect on penetration
resistance anywhere at the site. In order to determine the impact of either treatment on
infiltration rate or saturated hydraulic conductivity, more field data is required. Future
work will be conducted in June 2025 and every six months beyond to continue to
monitor the site.ente
The Delaware Food Farmacy: Integrating Medically Tailored Groceries and Community Health Workers into Chronic Disease Management
No full textThis article was originally published in Delaware Journal of Public Health. The version of record is available at: https://doi.org/10.32481/djph.2025.11.05
Copyright (c) 2025 Delaware Academy of Medicine / Delaware Public Health Association. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (https://creativecommons.org/licenses/by-nc-nd/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.Objective: This study evaluates whether a medically tailored grocery intervention supported by community health workers improves clinical, behavioral, and social outcomes among patients with diet-related chronic conditions. The Delaware Food Farmacy (DFF), a six-month program implemented by Christiana Care, targeted adults with diabetes, hypertension, or heart failure. Methods: This retrospective pre-post quasi-experimental study analyzed intake and six-month data for 185 participants enrolled between 2021 and 2024. Participants received weekly home deliveries of groceries aligned with the DASH diet, cooking tools, and ongoing support from community health workers (CHWs). Outcomes included food security, depression (PHQ-9), anxiety (GAD-7), BMI, blood pressure, and HbA1c. Results: Results indicated significant improvements in food security (p = 0.008), depression (–2.19 points, p < 0.001), anxiety (–1.76 points, p = 0.001), BMI (–1.44 kg/m2, p = 0.020), and HbA1c (–0.52%, p = 0.027). Goal completion averaged 84%, and satisfaction exceeded 90% across all program components. Conclusions: Findings demonstrate that medically tailored grocery programs supported by community health workers can produce measurable improvements in health and social outcomes among medically complex, low-income adults, offering a scalable, equity-oriented model to address chronic disease and inform value-based reimbursement pathways
Examining the influence of unmet needs on psychosocial predictors of health behavior in emerging young adult men with intersecting minority identifications
No full text"At the request of the author or degree granting institution, this graduate work is not available to view or purchase until March 05 2030"--Proquest citation/abstract page.Saylor, Jennifer L.Historically, examination of health outcomes has typically been examined within samples of the population in isolation without consideration of a variety of socioeconomic influences on the interplay between human behavior and health outcomes. This is particularly relevant when discussing the emerging young adult population. During a time of developmental instability, health behaviors could irrevocably alter one’s life course through the development of maladaptive coping mechanisms leading to substance use disorders and potential infectious disease transmission. The studies contained within this dissertation examine a vulnerable population who face both intrinsic and extrinsic challenges to optimal health states related to their intersecting identifications as both a racial/ethnic and a sexual minority. ☐ This dissertation aims to examine and describe the impact of the roles of socioeconomic disadvantage, and psychological constructs that could potentially impede emerging young adult sexual minority men (EYASMM) from attaining their presumed desired health states. Through a systematic review of the extant literature (Chapter Two), needs for definition and elucidation of influencing extrinsic factors on behavior are determined and discussed. This systematic review begins as an examination of risk-taking behavior in EYASMM and then discusses three themes gleaned from the literature. The three themes elicited from the literature share a common assertion that the interactions individuals encounter have potentially life-changing repercussions both immediately, and later in the life course. The quantitative research questions posed by the studies contained in this dissertation are answered through secondary data analyses of the Healthy Young Men’s Cohort Study (HYMCS) dataset. The HYMCS is a 14-wave longitudinal study that examines HIV transmission and reduction within the context of economic, and psychosocial barriers to care as well as a variety of health behaviors including substance use, healthy sex practices, pre-exposure prophylaxis (PrEP) usage and adherence as well as HIVrelated behaviors. This study examines individuals ages 16-24 years old who identify as Hispanic/Latinx, Black/ African American/ or Afro-Latinx. Study data were provided to the primary researcher of this dissertation after a publication proposal and exchange of ideas with the primary research team was accepted. This dissertation examines the roles of unmet basic needs on two pathways to explain health behavior. Study Two (Chapter Three) of this dissertation examines the association of unmet basic needs on problematic alcohol use. Further, the researchers of this study inquire if the use of substances to cope mediates the relationship between these two variables. Multivariable regression models determined that there was a statistically significant association between increasing age, Hispanic/Latinx identification, completion of a four-year undergraduate degree or higher, and substance use coping and problematic alcohol use. Despite these assertions, there was no statistically significant association between unmet basic needs and problematic alcohol use. Mediated regression analysis was performed and despite the absence of a direct causal pathway explaining problematic alcohol use as a behavior, an indirect effect was statistically significant providing the researchers with an opportunity for further research. Since this indirect effect does suggest an economic mediation to explain this causal pathway, selection of a different variable or framing of the research question could provide more evidence for the influences of personal socioeconomic considerations for problematic alcohol use interventions. Study Three (Chapter Four) of this dissertation examines the health behavior of condom self-efficacy within a socioeconomic context. Essential to the reduction of HIV and STI transmission, an examination of behaviors reducing this public health crisis is warranted. Using a mean measure of social support from three sources (friends, family, and significant other) to quantify perceived social support, the relationship between social support and condom self-efficacy was established, in alignment with the extant literature. Multivariable regression of demographic covariates yields that the only significant association was that of employment on condom self-efficacy. Moderated regression to determine the degree of influence of unmet needs on the association between social support and condom self-efficacy does not find an influence of the moderating variable. Therefore, condom self-efficacy is determined to be more of a socially mediated behavior than an economically influenced behavior. The studies within this dissertation demonstrate that there is a need for researchers, particularly in nursing, to develop a clear, population-specific definition of financial insecurity that captures those challenges encountered by EYASMM when it comes to health behaviors. In addition, the findings demonstrate a need for policy that embraces financial insecurity as a potential confounder of poor health outcomes in those thought not to be affected by poorer health as a function of age.University of Delaware, School of NursingPh.D
UNDERSTANDING THE DRUG INTERACTIONS WITH STIMULI-RESPONSIVE ELASTIN-COLLAGEN NANOVESICLES
No full textenterElastin-like peptides (ELPs) and collagen-like peptides (CLPs), synthetic
peptides which mimic natural elastin and collagen, respectively, are a promising class
of materials for drug delivery. ELP-CLP conjugates self-assemble into nanovesicles
that can encapsulate drugs, such as methotrexate and doxorubicin. To improve the
drug encapsulation and release efficiency of ELP-CLP nanovesicles, a strong
understanding of the interactions between elastin-like peptides and the small drugs is
critical. In this thesis, atomistic molecular dynamics simulations are used to study the
interactions between three ELP sequences (VPGXG), where X = F, W, Y, and two
drug molecules, methotrexate and doxorubicin. The VPGYG-DOX complex is
identified as the most stable ELP-drug complex, with a binding time of 99.0 ns, due to
strong π-π stacking and hydrogen bonding interactions. VPGFG-MTX is the second
longest binding complex, stabilized by hydrogen bonding interactions between the
glycine, proline, and MTX. Lastly, it is found that the tryptophan (W) stabilizes the
third longest bound VPGWG-DOX complex through parallel π-π stacking interactions
between W’s indole ring and the hydroquinone ring of DOX.ente
Passive strain sensing for structural health monitoring of civil infrastructure using retroreflective sheeting materials
No full textShenton, Harry W., IIIStructural health monitoring (SHM) is the implementation of sensors on a structure that allow engineers to evaluate the condition of the structure in a non-destructive, quantitative manner. SHM systems consist of sensing networks and data acquisition that are designed to provide information early on, before problems become too serious, and therefore reduce maintenance and repair costs and extend the life of structures. For bridges, SHM systems are not required, and are typically only implemented on very large and important structures where the return on investment is clear; however, smaller bridges could also benefit if structural health monitoring systems were implemented on them. Therefore, it is desirable to create a cost-effective solution so that SHM of smaller bridges is attainable. This can be achieved by creating a new passive sensor that utilizes materials and technologies that bridge owners are already familiar with. ☐ Retroreflective sheeting materials (RRSM) are used to make highly reflective traffic signs, and state Departments of Transportation (DOTs) are required to demonstrate that they meet minimum levels of retroreflectivity (RR), which can be measured using a handheld retroreflectometer. Many of these agencies also fabricate their own traffic signs. Thus, DOTs have familiarity with RRSMs and RR measurements. State DOTs also own a large percentage of the nation’s bridge infrastructure. Therefore, if RRSMs could be used to monitor strain in bridges, it would be an effective, straightforward and innovative way to encourage more frequent SHM of typical bridges. ☐ For this work, a total of 15 unique RRSM materials were evaluated for potential use as a passive strain sensor for structural health monitoring. They included 5 different ASTM standard types, 2 manufacturers and a variety of colors. The materials were subjected to various mechanical tests. First, all materials were subjected to tension testing, and it was determined that as strain is induced in RRSMs, their retroreflectivity decreases. Many materials have a linearly decreasing relationship between RR and strain. The sensitivity of each material’s RR to strain is a key parameter in determining viability for strain sensing. Materials with higher sensitivities were down selected for further testing, which included mounting the materials to steel and testing them in tension. Results showed that materials’ RR was not as sensitive to strain when it was mounted to a substrate as when it was tested on its own. Exploration into remedies for this were studied and ultimately a single material was chosen to be the best candidate for passive strain sensing of civil infrastructure. This material must be strained prior to use as a sensor. To accommodate this pre-straining, a production sensor was developed and tested. Ultimately, the RRSM sensor was able to be used to accurately predict strain in a beam loaded in four-point bending. ☐ Results show that RRSMs are affected by changes in temperature and an RR-Temperature relationship was developed for the final down selected material. When measuring RR of an in-place sensor to calculate structure strain, the RR value needs to be adjusted for the change in temperature between the time of installation and the time of RR reading. The process for fabricating, installing and reading an RR sensor was developed and is laid out in a stepwise manner for simplicity. In addition to this, various materials were microscopically evaluated to determine the fundamental mechanism by which RRSMs change when loaded. Finite element models were developed to provide additional insight into the material behavior under load. Finally, ASTM Type XI materials were subjected to exposure testing to determine how RR and adhesion change with continued exposure to the environment. ☐ This research led to a better understanding of RRSMs and how they respond to strain. This understanding can be used to create and implement a low-cost and accessible passive strain sensor that can be used on bridges to passively monitor their strain. RRSM sensors are thought to be an initial detector of a problematic structure, and not a solution to a deficient bridge. Bridge owners have access to and familiarity with RRSMs and retroreflectometers to measure their RR, which should lower the burden for transfer of technology and make the use of these sensors simple which ideally will encourage quantitative analysis of more bridges.University of Delaware, Department of Civil, Construction and Environmental EngineeringPh.D
Technology Acceptance and Perceived Learning Outcomes in Construction Surveying Education: A Comparative Analysis Using UTAUT and Bloom’s Taxonomy
No full textThis article was originally published in Education Sciences. The version of record is available at: https://doi.org/10.3390/educsci16010045
© 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license. https://creativecommons.org/licenses/by/4.0/Rapid adoption of digital surveying technologies in construction has highlighted the need for engineering education to equip students with technological competency as well as higher-order problem-solving skills. This experiment explores undergraduate students’ acceptance of emerging surveying technologies and their perceived learning results within a constructivist framework of experiential learning. Thirty-six students in a required construction surveying class interacted with traditional and advanced technologies such as total stations, terrestrial laser scanning, drones, and mobile LiDAR through structured, semi-structured, and unstructured lab activities. Data were gathered based on two post-course surveys: a technology acceptance survey grounded in Unified Theory of Acceptance and Use of Technology (UTAUT) and a self-perceived cognitive learning outcome survey through Bloom’s Taxonomy. Qualitative analysis along with quantitative analysis indicated a gap between technology acceptance and perceived learning gains. Laser scanner had the greatest acceptance scores followed by other advanced tools. Total station (widespread in hands-on lab activities) was perceived to have been most influential in terms of enhancing learning. Lower-order skills were strengthened in structured labs, while higher-order thinking emerged more unevenly in open-ended labs. These findings underscore that the mode of student engagement with technology matters more for learning than the sophistication of the tools themselves. By embedding UTAUT and Bloom’s Taxonomy in an authentic learning environment, this experiment provides engineering educators a mechanism to assess technology-enhanced learning and identifies strategies to facilitate higher-order skills aligned with industry needs.This research received no external funding
"Receptacles of Filth": A Sensory History of Early American Bedpans, 1750 to 1830
No full textBedpans made and used in the early United States appear in historic house museums and other cultural heritage institutions throughout the country. More often than not, however, these objects are hidden in plain sight. Informed by object-centered approaches to material culture studies as well as disability history and sensory studies scholarship, this thesis asks what these oft-ignored “receptacles of filth” might reveal about the early American sick-chamber and the twentieth-century house museum. Specifically, it examines histories of medicine, caregiving labor, and illness or infirmity in the home. This thesis begins with a case study of a late eighteenth-century pewter bedpan on display at Winterthur Museum, Garden & Library, which took on new meaning as a relic of the early American past in the midst of the twentieth-century Colonial Revival. While its seemingly pristine pewter surface might dazzle the eye, the history of the bedpan is also that of the nose, the hands, the digestive organs, and (of course) the rear end. Eighteenth and nineteenth-century receipt books, housekeeping manuals, medical journals, and satirical cartoons that make reference to bedpans or chamber pots attest to the ongoing battle doctors, nurses, domestic servants, and other caregivers waged against “dirt” in the sick-chamber. Dirty substances such as urine and excrement were more than just what anthropologist Mary Douglas has called “matter out of place.” The sight, smell, and feel of these substances were a source of great anxiety in late eighteenth and early nineteenth-century Anglo-American subjects. Finally, this thesis considers the bedpan as commercial good, examining both highly decorative bedpans used in early America as well as the wide array of antique bedpans available for purchase in secondhand stores and e-sellers such as Etsy and e-Bay. Such objects attest to bedpans as a source not just of revulsion but, in certain cases, of aesthetic pleasure. While bedpans may be out of sight and out of mind for most twenty-first century Americans, these objects remain not just literal receptacles of filth but symbolic receptacles of meaning. The study of bedpans is the study of the complex relationships between people, their bodies, and their waste
Seismic imaging of the Ecuadorian forearc and arc from joint ambient noise, local, and teleseismic tomography: catching the Nazca slab in the act of flattening
No full textThis article has been accepted for publication in Geophysical Journal International © The Author(s) 2025. Published by Oxford University Press on behalf of The Royal Astronomical Society. All rights reserved. The version of record is available at: https://doi.org/10.1093/gji/ggaf120.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.The Ecuadorian Andes are a complex region characterized by accreted oceanic terranes driven by the ongoing subduction of the oceanic Nazca plate beneath South America. Present-day tectonics in Ecuador are linked to the downgoing plate geometry featuring the subduction of the aseismic, oceanic Carnegie Ridge, which is currently entering the trench. Using seismic tomography, we jointly invert arrival times of P and S waves from local and teleseismic earthquakes with surface wave dispersion curves to image the structure of the forearc and magmatic arc of the Ecuadorian Andes. Our data set includes > 100 000 traveltimes recorded at 294 stations across Ecuador. Our images show the basement of the central forearc is composed of accreted oceanic terranes with high elastic wave speeds. Inboard of the Carnegie Ridge, the westernmost forearc and coastal cordilleras display relatively low Vp and Vs and high Vp/Vs values, which we attribute to the increased hydration and fracturing of the overriding plate due to the subduction of the thick oceanic crust of the Carnegie Ridge. We additionally image across-arc differences in magmatic architecture. The frontal volcanic arc overlies accreted terranes and is characterized by low velocities and high Vp/Vs indicative of partial melt reservoirs which are limited to the upper crust. In contrast, the main arc displays regions of partial melt across a wider range of depths. The Subandean zone of Ecuador has two active volcanoes built on continental crust suggesting the arc is expanding eastwards. The mid to lower crust does not show indications of being modified from the magmatic process. We infer that the slab is in the process of flattening as a consequence of early-stage subduction of the buoyant Carnegie Ridge.This work was supported by NSF grants EAR-1723065, EAR-1723042, EAR-2321410 and EAR-1951202. Thanks to the research and technical staff at Instituto Geofisico at the Escuela Politécnica Nacional (IG-EPN) in Quito, Ecuador for excellent logistics and field support. Thanks to the EarthScope PASSCAL Instrument facility for supporting instrumentation used in the U.S. portion of the Pedernales aftershock deployment. Additional instrumentation and data collection came from L'Institut de recherche pour le développement (IRD), Géoazur in Nice France, and University of Liverpool UK. We also thank Donna Shillington and an anonymous reviewer for their insightful feedback and improvements to our manuscript. This article has a Los Alamos National Laboratory (LANL) Unlimited Release Number (LA-UR-24–22829)