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A Preliminary Study on the Quantitative Assessment of Building Information Modeling and Virtual Reality in Supporting Mechanical, Electrical, and Plumbing Plan Comprehension in AECO Education
No full textThis article was originally published in Cureus Journal of Engineering. The version of record is available at: https://doi.org/10.7759/s44388-025-03233-8.
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© Copyright 2025
Aljagoub et al. This is an open access article distributed under the terms of the Creative Commons Attribution License CC-BY 4.0., which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
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This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Mechanical, Electrical, and Plumbing (MEP) systems are complex, often leading to conflicts and cost overruns. Yet, limited literature explores how to improve MEP plan reading in the classroom. The authors sought to fill the limited research gap through a pilot quantitative comparative study. Therefore, the effectiveness of Building Information Modeling-Virtual Reality (BIM-VR) implementation in a classroom to enhance MEP plan reading comprehension and spatial cognition was investigated, as many students struggle to interpret 2D plans due to their intricate nature. BIM-VR models were developed, and a group of students with limited prior-experience were chosen to minimize prior knowledge biases. Participants were randomly assigned to control and test groups and tested in two phases. The control group was provided 2D plans only, while the test group was granted access to BIM-VR models during the post-phase. Pre- and post-quizzes and a questionnaire were used to evaluate BIM-VR effectiveness, employing appropriate statistical methods. The test group performed similarly in the pre-phase and outperformed the control group in the post-phase. The questionnaire results indicated enhanced visualization, error detection, and a positive experience. The study findings promoted the need for academia to adopt BIM-VR, specifically within the context of MEP plan reading, to prepare students for industry demands
Alterations to non-traditional care settings during disasters: lessons learned from the COVID-19 response
No full textHorney, JenniferIn a typical disaster or public health emergency, there is an expected, and somewhat predictable, temporary discontinuation of care mainly due to damage of healthcare infrastructure. The COVID-19 pandemic exacerbated existing inequities in access to care that to some extent are related to inequities in social determinants of health such as access to housing. One approach to addressing the existing and growing number of health inequities has been the use of community-based interventions that deliver direct care and services such as mobile healthcare clinics. Alternative care settings such as mobile health clinics have been successfully used to address issues related to access to healthcare generally, as well as in response to disasters and emergencies. However, during the COVID-19 pandemic, the largest public health emergency response to date, mobile health units were limited by many of the non-pharmaceutical public health control measures put into place in response to the pandemic. This dissertation documented the utilization of alternative care delivery in disaster situations in international and domestic settings, identified disruptions to alternative care settings that resulted from the response to the COVID-19 pandemic, and identified aspects of structural capacity that could enable the continuity of service provision during disasters and emergencies, which could therefore decrease inequities of the health impacts of disasters. Through a scoping review and the use of convergent methodology, this dissertation highlights the need to improving baseline care within communities prior to a disaster and focusing on community connection, organizational capacity, and informational capacity to ensure the provision of care.Ph.D.University of Delaware, Epidemiology Progra
Resource substitutability path for China’s energy storage between lithium and vanadium
No full textThis article was originally published in iScience. The version of record is available at: https://doi.org/10.1016/j.isci.2025.112462.
© 2025 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY-NC license (http://creativecommons.org/licenses/by-nc/4.0/).Highlights
• L-V model reveals mutualistic LIB-VRB dynamics in China’s energy storage
• Vanadium’s substitutability elasticity declines as lithium prices rise
• VRBs penetrate market under low vanadium/high lithium price scenarios
• Optimal path: Planning trajectory pre-2030, radial expansion post-2030
Summary
The limited availability of lithium resources is often considered as potential constraints for the wide implementation of lithium-ion battery (LIB) energy storage technology. Alternative storage solutions, such as vanadium redox flow batteries (VRBs), are thus gaining traction as viable substitutes for LIB energy storage. However, how price volatility and cost affect technology substitution and thus scale and dynamics of energy storage market remains hitherto poorly characterized. Here, we construct a binary mineral resource substitution model within the energy storage sector of China, integrating energy storage costs with the prices of lithium carbonate and vanadium pentoxide. We reveal a mutualistic relationship between LIB and VRB, where the substitutability elasticity of vanadium pentoxide prices relative to lithium carbonate prices gradually decreases as prices rise. Through scenario simulations, we explore various price scenarios and strategic development paths, finding that VRBs show potential for market penetration when vanadium prices are low and lithium carbonate prices are high or moderate. The optimal transformation path is to follow the planning path until 2030 and then transition to the radial path until 2060.
Graphical abstract available at: https://doi.org/10.1016/j.isci.2025.112462This research was funded by National Science and Technology Major Project of the Ministry of Science and Technology of China (2024ZD1002002), National Natural Science Foundation of China (72204235, 72334001, 71991482, 72074197), the Major project of the National Social Science Foundation of China (21&ZD106), China Postdoctoral Science Foundation (2022M722948), the project of Sichuan Mineral Resources Research Center (SCKCZY2023-YB015), and the Fundamental Research Funds for National Universities of China University of Geosciences
ENHANCED TARGETING OF MEGAKARYOBLASTIC LEUKEMIA BY CANCER CELL MEMBRANE-WRAPPED POLYMER NANOPARTICLES TO INHIBIT β-CATENIN THROUGH SIRNA DELIVERY
No full textenterAcute megakaryoblastic leukemia (AMKL) is a rare and aggressive form of leukemia
characterized by an overabundance of β-catenin signaling, which contributes to
leukemogenesis and therapeutic resistance. Small interfering RNA (siRNA) offers a
targeted approach to silencing oncogenic drivers like β-catenin, but its clinical
application remains limited due to delivery challenges. This thesis focuses on the
development and optimization of polymeric nanoparticles for the targeted delivery of
β-catenin siRNA into AMKL cells. Sixteen unique nanoparticle formulations were
synthesized and systematically characterized based on hydrodynamic diameter, ζ potential, and encapsulation efficiency. These formulations were evaluated for their
cellular uptake efficiency in AMKL cells, cytocompatibility via Alamar Blue assay,
and gene silencing of β-catenin using immunofluorescent flow cytometry. Results
identified lead formulations capable of efficient siRNA encapsulation and intracellular
delivery, with significant downregulation of β-catenin. This work demonstrates the
feasibility of using polymeric nanoparticles as a vehicle for RNA interference-based
therapy in AMKL and lays the groundwork for future studies focused on in vivo
delivery, long-term therapeutic efficacy, and immune compatibility.ente
Mixed traffic control and coordination: optimization and learning-based approaches
No full textMalikopoulos, Andreas A.Traffic crashes in the United States resulted in over 44,000 fatalities in 2024, with human error contributing to approximately 94% of these incidents. Automated driving technologies offer a promising solution to reduce human error and improve road safety. Beyond safety, connected and automated vehicles (CAVs) are expected to alleviate congestion, lower energy consumption, and enhance traffic efficiency. However, realizing these benefits at scale requires effective control and coordination strategies in mixed-traffic environments where CAVs share the road with human-driven vehicles (HDVs). This dissertation addresses the control and coordination problem for CAVs in mixed-traffic interaction-driven scenarios, such as intersections and merges. Three key challenges need to be addressed: (i) real-time optimization and control for interacting multi-agent systems, (ii) understanding human behavioral models and integrating those prediction models into control, and (iii) developing human-compatible control designs that are safe, robust, efficient, and able to adapt. To address these challenges, we leverage the intersection of control, optimization, and machine learning to propose three contributions: (i) a learning-to-adapt framework for model predictive control under varying human driving styles; (ii) a stochastic time-optimal trajectory planning approach incorporating data-driven car-following models; and (iii) a distributed, learning-aided mixed-integer quadratic programming framework for the joint coordination of traffic lights and CAVs. ☐ The first contribution of this dissertation is the development of a learning-to-adapt control framework that enables model predictive control (MPC) to account for varying human driving behaviors. It integrates a game-theoretic MPC formulation for CAV-HDV interactions, online inverse learning of human driving intent, and an optimal weight adaptation strategy. Since computing the optimal adaptation is computationally expensive and involves black-box evaluations, in a sim-to-real manner, the framework employs Bayesian optimization and contextual Bayesian optimization to efficiently learn how to adapt MPC weights based on the inferred human objectives. ☐ The second contribution of this dissertation introduces a stochastic time-optimal trajectory planning framework for coordinating multiple CAVs in mixed-traffic merging scenarios. The approach leverages a time-optimal control problem formulation for CAVs and incorporates a data-driven Newell's car-following model with Bayesian linear regression to predict HDV behavior, together with uncertainty qualification. Safety constraints are enforced probabilistically for robust yet efficient trajectory planning. To account for prediction errors, a replanning mechanism is developed based on monitoring the accuracy of HDV trajectory prediction. ☐ The third contribution focuses on the coordination of CAVs and traffic lights at complex intersections in mixed traffic. We propose a joint optimization framework allowing simultaneous green signals on conflicting lanes when no HDV-related lateral conflicts exist, enabling more efficient use of CAV coordination. We formulate this as a multi-agent mixed-integer quadratic program and develop a distributed solution using a variant of the maximum block improvement algorithm with penalization of local constraints. Moreover, we proposed a graph machine learning approach that learns the mapping from problem parameters to optimal binaries offline, enabling fast online control by solving convex quadratic programs. ☐ Collectively, this dissertation contributes toward safe, interaction-aware, robust, and efficient trajectory planning methods for CAVs in mixed traffic. Moreover, by leveraging the coordination of CAVs both with and without traffic signals as CAV penetration rates increase, overall traffic performance can be remarkably improved. Beyond mixed-traffic connected and automated driving, the proposed frameworks, particularly learning-based control, learning to adapt, or distributed and learning-aided mixed-integer optimization, can be extended to broader cyber-physical human systems.University of Delaware, Department of Mechanical EngineeringPh.D
Characterization and mitigation of permeability in 3D printed oscillating heat pipes and a conjugate heat transfer study at adiabatic section of OHP's
No full textFeser, Joseph P.Oscillating Heat Pipes are a phase-change heat transfer device designed to move heat from a hot source to a cold source efficiently, exploiting oscillations of fluid slugs within tubes driven by vapor pressure differences generated between the hot/cold sides. There are two general geometries typically used to construct these devices: tube and flat-plate. This thesis addresses two different aspects of OHP’s. ☐ In the first part, this study examines the feasibility of utilizing 3D-printed sintered stainless steel parts, fabricated from Ultrafuse 17-4 PH (”Ultrafuse”) filament, as a cost-effective alternative OHP material. While additive manufacturing (AM) using fused filament fabrication (FFF) significantly reduces production costs and enables the creation of complex internal channels for enhanced thermal performance, OHPs are required to be vacuum-tight, and FFF made parts generally have some porosity. To gain understanding of the porosity of this material, measurement apparatuses were made to measure both the in-plane and through-plane Darcy permeability FFF samples. The apparatuses are based on compressed gas transport and appropriate compressible equations data extraction are developed. In addition to sintered Ultrafuse, it is also explore whether electroplating processes (both Nickel and Copper) can be used to improve/reduce the permeability of these materials. Microstructural analyses via scanning electron microscopy (SEM) is also employed to measure the pore density and sizes, both before and after plating. SEM confirmed that there are 50 micron pores in the final Ultrafuse parts that form in between adjacent nozzle paths, and these form an array that has spacing of 1 nozzle width x 1 layer height. These pores form in the print plane. In some cases, the pores connect to form cracks connect adjacent layers. It was found that electroless plating using Nickel, filled the surface cracks/pores of these samples and reduced permeability to an immeasurably-low value. Adhesion between electroplated copper and stainless steel was not strong and did not lead to parts with significantly lower permeability. ☐ In the second part, the effect of conjugate heat transfer in the adiabatic section of an OHP is explored experimentally. A modular OHP setup was designed to evaluate how different adiabatic section materials—copper, aluminum, and brass—which have significantly different thermal effustivity and diffusivity affect thermal behavior under controlled conditions. The system includes a uniform heat source using a polyimide heater, embedded thermocouples along the length of the pipe, and a water-cooled condenser. Importantly the evaporator and condenser sections are identical/re-used for each each experiment. The adiabatic section was made interchangeable to isolate the influence of wall conductivity. Acetone was used as the working fluid, filled to 65% of the internal volume, based on prior optimization studies. It was found that the conductance of the OHP with copper adiabatic section had performance ∼30% worse than either aluminum or brass, but otherwise was of similar scale considering the large differences in material properties.University of Delaware, Department of Mechanical EngineeringM.S.M.E
Inflationary paradigms, observable gravitational waves and dark matter in grand unified theories
No full textMacDonald, JamesRehman, Mansoor UrObservations of the cosmic microwave background (CMB) have confirmed key predictions of inflation, including a nearly scale-invariant spectrum of primordial perturbations that are predominantly Gaussian and adiabatic. The same mechanism that drives cosmic structure formation may also generate a stochastic background of primordial gravitational waves (PGWs), which imprint a distinctive signature on CMB polarization. A confirmed detection of this tensor signal would yield unprecedented insights into high-energy physics and the dynamics of the inflationary epoch. This work investigates realistic inflationary models within the framework of grand unified theories (GUTs), emphasizing their implications for observable cosmology, gravitational waves, and dark matter. These models naturally resolve the primordial magnetic monopole problem while yielding a scalar spectral index n_s in excellent agreement with recent observations and predicting an observable tensor-to-scalar ratio r—characterizing the amplitude of primordial gravitational waves—potentially within reach of upcoming CMB experiments such as LiteBIRD, CMB-S4, and the Simons Observatory. In addition, these models incorporate a realistic scenario of reheating and non-thermal leptogenesis, offering a compelling explanation for the observed baryon asymmetry of the universe. It is further shown that symmetry breaking in certain GUT scenarios gives rise to metastable cosmic strings, which generate a stochastic gravitational wave background (SGWB) that may explain the recent signal observed by NANOGrav and other pulsar timing array (PTA) experiments. Various possibilities are explored in realistic GUT frameworks where such a metastable cosmic string network naturally emerges at the end of inflation, providing a viable origin for the SGWB. This background also lies within the sensitivity range of future gravitational wave observatories, including SKA, LISA, and DECIGO. In addition, this work explores mechanisms that enhance the primordial curvature power spectrum at small scales, leading to the formation of primordial black holes (PBHs) and scalar-induced secondary gravitational waves (SIGWs). The resulting PBHs may account for all or part of the dark matter abundance, while their associated SIGWs offer an independent probe for gravitational wave observatories such as LISA, SKA, DECIGO, and BBO. Finally, several co-annihilation scenarios are studied where the lightest neutralino serves as a viable dark matter candidate through sbottom-neutralino, stop-neutralino, and gluino-neutralino co-annihilation, consistent with bottom-tau Yukawa unification. These solutions satisfy collider constraints, relic density bounds, and direct and indirect detection limits, with parameter spaces potentially testable at LHC Run-3 and future collider experiments.University of Delaware, Department of Physics and AstronomyPh.D
Conversion of Compositionally Diverse Plastic Waste over Earth-Abundant Sulfides
No full textThis document is the Accepted Manuscript version of a Published Work that appeared in final form in Journal of the American Chemical Society, copyright © 2025 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/jacs.4c18001.
This article will be embargoed until 04/02/2026.Chemical deconstruction of polyolefin plastic wastes via hydroconversion is promising for mitigating plastic accumulation in landfills and the environment. However, hydroconversion catalysts cannot handle complex feedstocks containing multiple polymers, additives, and heteroatom impurities. Here, we report a single-step strategy using earth-abundant metal sulfide catalysts to deconstruct these wastes. We show that NiMoSx/HY catalysts deconstruct polyolefin feedstocks, achieving ∼81–94% selectivity to liquid products. Postsynthetic zeolite modification enhances the catalyst’s activity by >2.5 times, achieving over 95% selectivity to liquid fuels with controllable product distribution in the naphtha, jet fuel, and diesel range. The catalyst is resilient to increasingly complex feedstocks, such as additive-containing polymers and mixed plastics composed of polyolefins and heteroatom-containing polymers, including poly(vinyl chloride). We extend the strategy to single-use polyolefin wastes that can generate toxic byproducts, such as HCl and NH3, and eliminate their emissions by integrating reaction and sorption in a one-step process.This work was financially supported by the IEDO Office of the Department of Energy (DOE) under grant number PS 23A00753. It used instruments in the Advanced Materials Characterization Lab (AMCL), the W. M. Keck Center for Advanced Microscopy and Microanalysis, and the Mass Spectrometry Facility at the University of Delaware. The GPC and rheology work was supported as part of the Center for Plastics Innovation, an Energy Frontier Research Center funded by the US Dept. of Energy, Office of Science, Office of Basic Energy Sciences under award number DE-SC0021166. The authors also thank Kelly Walker for her assistance with the TOC graphic
Navigating the politically charged classroom: Using inquiry to teach contentious social studies
No full textThis is an Accepted Manuscript of an article published by Taylor & Francis in Theory Into Practice on 02/07/2025, available at: https://doi.org/10.1080/00405841.2025.2453371.
© 2025 The College of Education and Human Ecology, The Ohio State University.
This article will be embargoed until 08/07/2026.Teaching social studies during politically volatile times is challenging. This article draws from the findings of an explanatory case study that examined 2 teachers’ instructional choices as they taught contentious social studies. The researchers sought to understand how the teachers navigated conflicting educational ideologies through their instructional choices when designing and delivering inquiry-based instruction. Data consisted of interviews, observations, and artifacts and was analyzed using a thematic approach with the Questions, Tasks, and Sources [QTS] Observation Protocol and the Framework for Teaching Controversial Issues serving as the analytical framework. From this study, we offer instructional strategies for navigating the challenges of teaching contentious social studies through an inquiry-based curriculum. We note how teachers can craft democratic compelling questions, select sources that contextualize contentious social studies, and plan for formative and summative performance tasks to support more deliberative argumentation