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Smart and Sustainable Sizing: Investigating the Sensing Behavior of Glass Fabrics Coated With Waterborne Polyurethane/Graphene Dispersions
No full textThis is an open access article under the terms of the Creative Commons Attribution-Non Commercial-No Derivs License, https://creativecommons.org/licenses/by-nc-nd/4.0/ which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.© 2026 The Author(s). Advanced Materials Technologies published by Wiley-VCH GmbH
This article was originally published in Advanced Materials Technologies. The version of record is available at: https://doi.org/10.1002/admt.202502030The study focuses on developing smart, sustainable sizing agents that impart functional properties to glass fabrics (GFs). Aseries of graphene/waterborne polyurethane (WPU) dispersions is formulated and optimised to transform insulative GFs into electrically conductive ‘smart’ fabrics with strain-sensing capabilities. The novelty of this work lies in a stable, water borne graphene sizing formulation that enables direct, single-step dip-coating of GFs, eliminating the need for multi-layer deposition,post-processing, or hazardous chemicals. Dispersion stability is assessed using T 2 relaxation time measurements on a nuclear magnetic resonance (NMR) spectrometer. The optimised formulation used to coat the GFs in this study exhibits good dispersion stability (T 2 value of 822.7 ms), higher than that of the other formulations developed. This enhanced stability directly contributed to uniform coating morphology and effective electrical conductivity across the GFs. Additionally, comprehensive material characterisation is conducted to analyse the structural, morphological, and chemical properties of the advanced graphene/WPU formulations. Electromechanical testing demonstrates reproducible piezoresistive behavior under cyclic compressive loading, with force estimation accuracy remaining below 10% (RMSE) for loads exceeding 1000 N and improving to below 4% for loads within1.2–5 kN. The force–conductance calibration shows strong reproducibility (R 2 ≈ 1), supporting reliable sensing performance under medium-to-high load regimes relevant to structural health monitoring (SHM). The findings of the study offer a sustainable and scalable alternative to traditional solvent-based systems, addressing environmental concerns while enabling high-performance applications in composite manufacturingThe author, VP, would like to acknowledge the Australian Research Council (ARC), the Defence Science Institute, and Swinburne University for the PhD scholarship. Authors VP, PG, NS, PK, FKF, and NH would like to thank the Australian Research Council for the ARC Linkage (LP200301659) research grant. Work at the University of Delaware was supported by AIM for Composites, an Energy Frontier Research Center funded by DOE, Office of Science, BES under Award#DE-SC0023389 (Material–Process–Microstructure–Performance (MP2)Relationships). XPS analysis was performed with the instrument sponsored by the National Science Foundation under Grant No. CHE-1428149.The authors thank all individuals and organisations who permitted us to republish their figures and other relevant information. The authors thank LANXESS Corporation for their in-kind support for the waterborne polyurethane dispersions. Open access publishing facilitated by Swinburne University of Technology, as part of the Wiley - Swinburne University of Technology agreement via the Council of Australasian University Librarian
Microbial reduction of nitrate and perchlorate through electron storage capacity of wood-derived biochar
No full textChiu, Pei C.Perchlorate and nitrate contamination pose significant environmental and health concerns globally. Human activities, including agriculture, livestock farming, and the production of munitions for military purposes, have significantly contributed to the elevated levels of nitrate and perchlorate pollution in the environment. Current physical and chemical remediation methods for these contaminants often have limitations and can generate additional environmental impacts. Microbial reduction has emerged as a promising approach, but traditional microbial substrates can produce toxic byproducts. In this study, we investigated the efficacy of wood-derived biochar as an exclusive electron donor for the microbial reductive transformation of nitrate and perchlorate into non-toxic products such as nitrogen gas and chloride. Our results demonstrated that biochar effectively facilitated the degradation of nitrate and perchlorate, even in small quantities. In just 4 days, 1 g of reduced biochar successfully facilitated the reductive transformation of 1.55 mM perchlorate into chloride. Similarly, within a span of 13 days, 0.5 g of biochar mediated the conversion of 3.8 mM nitrate into harmless N2. These transformation rates far exceed the established Maximum Contamination Level for perchlorate (300 times higher) and nitrate (30 times higher). Notably, these rates were reached much more rapidly compared to conventional microbiological methods, underscoring the exceptional efficacy of biochar as a remediation agent. Importantly, biochar did not generate any toxic byproducts, distinguishing it from previous methodologies. We also observed a proportionality between the mass of biochar and the rate and extent of reduction, providing valuable insights for system design. Biochar's affordability, environmental friendliness, and absence of toxic byproducts make it a promising tool for controlling nitrate and perchlorate fate and transport. Further research may be needed to assess its feasibility and scalability in real-world scenarios. Nevertheless, this study lays a solid foundation for advancing environmental engineering practices and mitigating pollution impacts associated with these contaminants.University of Delaware, Department of Civil, Construction and Environmental EngineeringM.C.E
Proline/sidechain C-H/O interactions stabilize cis-proline
No full textThis article was originally published in [Journal Name]. The version of record is available at: https://doi.org/10.1039/d5cp03423j
Open Access Article
This Open Access Article is licensed under a Creative Commons Attribution-Non Commercial 3.0 Unported Licence https://creativecommons.org/licenses/by-nc/3.0/Bioinformatics analysis was conducted on proteins in the PDB to identify local structures that can stabilize the cis-proline conformation. C–H/O interactions were observed between a sidechain oxygen and Pro C–Hα in the cis-proline conformation at Glu–Pro, Asp–Pro, Gln–Pro, Asn–Pro, Ser–Pro, and Thr–Pro sequences. These C–H/O interactions are apparently most stabilizing at Glu–Pro sequences, which have a substantially higher than average frequency of cis-proline (7.1% of all Glu–Pro amide bonds in the PDB). DFT calculations were conducted to understand the bases and geometries of C–H/O interactions in these sequences. Computationally, these residues all exhibit close C–H/O interactions (substantially below the 2.72 Å sum of the van der Waals radii of H and O), with the closest C–H/O interactions observed with the anionic oxygens of Glu and Asp, and with closer interactions for the anionic residues than the neutral carboxamides Gln and Asn. DFT calculations revealed that C–H/O interactions also stabilize cis-proline at phosphoserine–proline and phosphothreonine–proline sequences, with closer C–H/O interactions in the dianionic forms of phosphorylated residues that predominate at physiological pH. These results also provide an explanation for the observed higher activation barrier for amide bond isomerism at phosphoserine–proline and phosphothreonine–proline sequences. Calculations suggested that C–H/O interactions mediated by these residues could also stabilize non-proline cis amide bonds, which are often functionally important when observed.We thank NSF (CHE-2004110 and BIO-1616490) and the DOD CDMRP PRARP program (AZ140115) for funding. Instrumentation support was provided by NIH (GM110758) and NSF (CHE-1229234)
Using Advanced Tri-Axial Accelerometer Data to Improve Behavioral Time Budgets and Bioenergetic Estimates of Wintering Lesser Scaup
No full textThis is an open access article under the terms of the Creative Commons Attribution License, https://creativecommons.org/licenses/by/4.0/ which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
© 2025 The Author(s). Ecology and Evolution published by British Ecological Society and John Wiley & Sons Ltd.
This article was originally published in Ecology and Evolution . The version of record is available at: https://doi.org/10.1002/ece3.72868Wildlife behavior studies have provided vital information towards understanding the natural histories of wildlife species and identified crucial components regarding their habitat and metabolic needs. For many species, typical behavioral data are collected using diurnal scans that have limitations in both when and where the data can be collected, ultimately leading to biases in behavioral patterns. With technological and analytical advancements of radiotechnology, behavior data can be collected more often and over larger spatial scales than with traditional methods. This study compares the behavioral time budget estimates between two different observational methods: ground-truthed diurnal scanning observations and 24-h tri-axial accelerometer (ACC) GPS/GSM transmitter data that were classified using machine learning. We used the time budgets produced from the two methodologies and calculated the daily energy expenditure (DEE) for wintering Lesser Scaup (Aythya affinis) to explore the implications of biased behavioral data. We found significantly more feeding and less flight behavior of birds in the ACC data than in the visual scanning data. Using the ACC behavior proportions of the two most energetically demanding behaviors (feeding and flying), we found that feeding occurred 42% more during the day and flying occurred 23% more during the night. Lastly, we identified that the DEE estimated using the diurnal scanning observations produced a significantly lower estimate than with the 24-h ACC data. This advanced way of interpreting wildlife behavior patterns can increase our understanding of wildlife species' natural history and make improved decisions regarding wildlife conservation and management. Incorporating this new technique of wildlife behavioral observations, we provided a new framework to expand our current knowledge of wintering waterfowl behaviors and energetic needs that can be adapted to research the vast intricacies of wildlife behavior.Funding for this research came from the Maryland Department of Natural Resources, Ducks Unlimited, The University of Delaware Waterfowl and Upland Gamebird Center, and USDA Hatch (DEL00854). We are especially grateful to Matt Whitbeck and Marcia Pradines of the US Fish and Wildlife Service for providing access to Eastern Neck National Wildlife Refuge, the many biologists and technicians, specifically Nathan Simmons and Amanda Hoyt, of the Maryland Department of Natural Resources who helped during fieldwork, and Dr. Alicia Berlin, Carlyn Caldwell, and the staff of the US Geological Survey—Eastern Ecological Science Center for providing their expertise and facilities.
This work was supported by Maryland Department of Natural Resources and Ducks Unlimited. Additional funding was provided by the US Department of Agriculture Hatch (DEL00774) and the University of Delaware Waterfowl and Upland Gamebird Center
An economic assessment of nitrogen modeling tools in Delaware's Chesapeake Bay Watershed
No full textPalm-Forster, Leah H.Nitrogen (N) management plays a central role in balancing agricultural productivity and environmental protection. This study evaluates how different N recommendation methods influence farm profitability and environmental outcomes for corn production in the Delaware portion of the Chesapeake Bay Watershed. Using the Cycles agroecosystem model, we simulate crop yield, nitrate (NO₃) leaching, and nitrous oxide (N₂O) emissions across multiple soils, years, and management systems to compare three approaches: a standard Extension rate, an Extension rate with a soybean credit, and an in-season N modeling tool. ☐ Economic outcomes were assessed by combining simulated yields with market-based fertilizer and crop prices, while environmental costs were estimated using established per-unit social cost values for NO₃ and N₂O, adjusted to current dollars. This framework allowed evaluation of private benefits (profit), public (social) costs, and net benefits across management scenarios. ☐ The results show that Conservation systems generally achieved higher profits and lower environmental costs than Conventional systems. Among recommendation methods, the soybean credit and N-modeling tool produced lower application rates closer to both private and social optima, while the standard Extension method often resulted in over-application. Sensitivity analyses on prices and precipitation confirmed that these patterns held across a range of realistic conditions. Overall, both the soybean credit and N modeling approaches improve upon the status quo Extension recommendation, though their relative advantages depend on management context and growing conditions. Additionally, broader adoption of Conservation management practices may offer greater overall improvements in profitability and environmental outcomes.University of Delaware, Department of Applied Economics and StatisticsM.S
Exploring science and engineering curricula for two and three-year-olds: a multiple case study of early educators' curricula
No full textGallo-Fox, JenniferThis study examines how the Next Generation Science Standards Content Disciplines (Life science, Earth science, Physical science, and Engineering) are addressed across two early childhood curricula. The multiple case study content analysis examines one teacher’s classroom communications to families of her two-year-old and three-year-old half-day, preschool classes for the 2022-2023 school year. Data sources included in the secondary data set are the teacher’s weekly emails to families, weekly schedules, monthly Google photo albums shared with families, and two Classroom Science Walks. These resources provide rich insight into how the early childhood educator structured her science curriculum across the academic year (2022-2023). Findings indicate that the children actively engaged in daily hands-on science explorations each day and addressed each of the core science and engineering disciplines weekly. The curriculum for each age group was designed to be developmentally appropriate (NAEYC, 2014), fitting the children's needs and allowing them to engage in science activities in both indoor and outdoor settings. Children had opportunities to learn within a supportive, play-based environment designed to connect to the children’s natural curiosity and eagerness to explore. This study highlights ways that the early science curriculum enables children to design various objects, motivates deep thinking, supports interdisciplinary learning opportunities, builds problem-solving skills, and ultimately opens doors for socialization.University of Delaware, Department of Human Development and Family SciencesM.S
Coherently distributed RF antenna arrays using photonic links
No full textPrather, Dennis W.This thesis presents a coherently distributed multiple-input multiple-output (MIMO) radio-frequency (RF)-photonic system operating at millimeter wave (mmWave) frequencies. Over long distances with negligible propagation loss, this system uses radio-frequency-over-fiber (RFoF), or RF-photonic links, to implement distributed antenna system that preserves both the spatial and temporal coherence of RF signals. It utilizes the principles of photonic signal generation and the distribution of RF signals using a centralized optical local oscillator (OLO) to maintain phase and frequency coherence across antennas separated by tens of kilometers. Based on the proposed RF-photonic system architecture, this thesis presents the development and simulation of various antenna configurations, including single-array architectures, unconstrained distributions of subarrays and individual elements. These configurations are analyzed as proof-of-concept demonstrations to validate the precoding strategies, including zero forcing (ZF) and maximal ratio transmission (MRT), and their performance is evaluated using a simulation precoder design algorithm to establish the feasibility of the overall system design. ☐ This RF-photonic system also includes a photonic processing unit (PPU) that contains a tunable optical paired source (TOPS), photonic feed network that enables a complex weighting matrix, which enables phase and amplitude control in the optical domain to apply beamforming weights, and finally high-power photodiodes (PDs) in the remote RF frontend. The system is used to implement optimized complex weights, on distributed antenna elements, to realize “flat,” i.e., lying in the plane of propagation, holographic field profiles. In order to implement the practical performance of the holographic field profiles in the phase-synchronized distributed beamforming systems, hardware and software development are carried out. This distributed beamforming system includes the implementation of the transmitter (Tx) module, including both the software framework developed in LabVIEW and hardware enhancements achieved through the integration of supplementary test equipment for improved data acquisition and system monitoring. ☐ Various calibration techniques are used to obtain far-field radiation patterns and to maintain phase coherence across multiple distributed antennas. Experimental validation of a one-dimensional indoor system is used to demonstrate the aforementioned “in-plane” holograms, along with their comparison to simulation results. The experimental implementation and validation of various precoding schemes are utilized to implement the long range distribution of RF signals without being limited by cable loss. The proposed system preserves coherence even with differential fiber lengths to the different remote antennas. This system can be expanded to support multiple users by increasing the number of transmit antennas and incorporating data modulation on the coherent carriers. With these advancements, full system-level performance evaluation including data rate, spectral efficiency and bit error rate is planned for future work.University of Delaware, Department of Electrical and Computer EngineeringM.S
Interplanetary magnetic correlation and low-frequency spectrum over many solar rotations
No full textThis article was originally published in Proceedings of the National Academy of Sciences (PNAS). The version of record is available at: https://doi.org/10.1073/pnas.2519811122
Copyright © 2026 the Author(s). Published by PNAS. This article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). https://creativecommons.org/licenses/by-nc-nd/4.0/Fluctuations and structure across a wide range of spatial and temporal scales are frequently studied in the solar wind. The properties of the low-frequency fluctuations are of relevance to turbulent energy injection into the plasma and the transport of highenergy cosmic rays. Correlation analysis of decade-long intervals of interplanetary data permits study of fluctuations at time scales much longer than suitably defined correlation times, and therefore at frequencies well below those associated with the Kolmogorov inertial range of in situ turbulence. At the frequencies of interest, we study the familiar occurrence of the 1=f spectral signature. We also study point spectral features due to solar rotation and their relation with the 1=f signal. We report properties at timescales ranging from minutes up to years, using data selected by wind speed, phase of solar cycle, and cartesian components of the magnetic field. A surprising finding is that the power in solar rotation harmonics is consistent with an extension of the 1=f spectrum, down to frequencies as low as around 5 107 Hz. The presence of a broadband 1=f spectrum across different wind types supports the interpretation that 1=f signals may be related to or even originate from the solar dynamo.The velocity and density data were downloaded from https://spdf.gsfc.nasa.gov/pub/data/ace/swepam/level2_hdf/ions_64sec. The magnetic field data were downloaded from https://spdf.gsfc.nasa.gov/pub/data/ace/mag/level_2_cdaweb/mfi_h3/. This research is partially supported by the NASA LWS Grants 80NSSC22K1020, by the NASA IMAP project at UD under subcontract SUB0000317 from Princeton University, by the NASA/SWRI PUNCH subcontract N99054DS, and by NSF Grant AGS-2108834
Just-in-Time Adaptive Intervention to Promote Walking Behavior and Reduce Stationary Time in Physically Inactive Adults: Protocol for the Walking With JITAIs Study
No full text©Cora J Firkin, Ajith Vemuri, Tanvir Rahman, Barry Bodt, Elizabeth Orsega-Smith, Keith Decker, Gregory M Dominick. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 07.Jan.2026. 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 use, distribution, and reproduction in any medium, provided the original work, first published in JMIR
This article was originally published in JMIR Research Protocols. The version of record is available at: https://doi.org/10.2196/79022Background: A Just-in-Time Adaptive Intervention (JITAI) recognizes the dynamic nature of individuals’ states and contexts, predicts support needs, and sends tailored support at more opportune, actionable times.
Objective: This paper outlines the application architecture and protocol for the pilot “Walking With Just-in-Time Adaptive Interventions” (WWJ) study, which uses a JITAI approach to improve walking behavior—duration, speed, and distance—and
reduce stationary time, defined as idle sitting or standing.
Methods: This study targets 20 adults who are physically inactive and leverages the Apple Watch to deliver fully automated tailored intervention notifications to “walk faster,” “walk longer,” or “stand up and move around” based on real-time data and
contextual factors, including time-of-day activity patterns, geographic locations (eg, home, work, park, and gymnasium), weather conditions (eg, precipitation, wind speed, and humidity), and receptiveness. The protocol involves a preintervention assessment
of demographics, behavior change constructs, anthropometrics, and resting vital signs; a 2-week observation period to establish walking behavior and stationary time baselines; a 2-week just-in-time learning period to evaluate receptiveness to untailored
prompts at all applicable times; the 2-week JITAI intervention phase; and a postintervention assessment. Feasibility will be evaluated through protocol fidelity, participant adherence, Apple Watch wear-time compliance, user burden, acceptability ratings,
and perceptions of benefits and preferences.
Results: The WWJ architecture development began in spring 2021 and concluded in fall 2022. Participant recruitment and enrollment began in fall 2022. A total of 18 participants were recruited. Upon completion of the analyses, the results of this study
are expected to be submitted for publication.
Conclusions: Distinctively, the WWJ just-in-time learning period aims to train the learner based on user receptiveness within contexts by sending interventions whenever a participant meets the predetermined thresholds regardless of the likelihood that the
user will be receptive to the notification to prune out non opportune or “nonactionable” times. This approach may allow for greater customization during the JITAI period.This study was internally funded through the Center for Innovative Health Research (CIHR), University of Delaware